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  Subjects -> ENGINEERING (Total: 2277 journals)
    - CHEMICAL ENGINEERING (191 journals)
    - CIVIL ENGINEERING (183 journals)
    - ELECTRICAL ENGINEERING (103 journals)
    - ENGINEERING (1204 journals)
    - ENGINEERING MECHANICS AND MATERIALS (385 journals)
    - HYDRAULIC ENGINEERING (55 journals)
    - INDUSTRIAL ENGINEERING (66 journals)
    - MECHANICAL ENGINEERING (90 journals)

ENGINEERING (1204 journals)                  1 2 3 4 5 6 7 | Last

Showing 1 - 200 of 1205 Journals sorted alphabetically
3 Biotech     Open Access   (Followers: 7)
3D Research     Hybrid Journal   (Followers: 19)
AAPG Bulletin     Hybrid Journal   (Followers: 6)
AASRI Procedia     Open Access   (Followers: 15)
Abstract and Applied Analysis     Open Access   (Followers: 3)
Aceh International Journal of Science and Technology     Open Access   (Followers: 2)
ACS Nano     Full-text available via subscription   (Followers: 230)
Acta Geotechnica     Hybrid Journal   (Followers: 7)
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 5)
Acta Polytechnica : Journal of Advanced Engineering     Open Access   (Followers: 2)
Acta Scientiarum. Technology     Open Access   (Followers: 3)
Acta Universitatis Cibiniensis. Technical Series     Open Access  
Active and Passive Electronic Components     Open Access   (Followers: 7)
Adaptive Behavior     Hybrid Journal   (Followers: 11)
Adıyaman Üniversitesi Mühendislik Bilimleri Dergisi     Open Access  
Adsorption     Hybrid Journal   (Followers: 4)
Advanced Engineering Forum     Full-text available via subscription   (Followers: 6)
Advanced Science     Open Access   (Followers: 5)
Advanced Science Focus     Free   (Followers: 3)
Advanced Science Letters     Full-text available via subscription   (Followers: 7)
Advanced Science, Engineering and Medicine     Partially Free   (Followers: 7)
Advanced Synthesis & Catalysis     Hybrid Journal   (Followers: 17)
Advances in Calculus of Variations     Hybrid Journal   (Followers: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5)
Advances in Complex Systems     Hybrid Journal   (Followers: 7)
Advances in Engineering Software     Hybrid Journal   (Followers: 25)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 15)
Advances in Fuzzy Systems     Open Access   (Followers: 5)
Advances in Geosciences (ADGEO)     Open Access   (Followers: 10)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 21)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 25)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 9)
Advances in Natural Sciences: Nanoscience and Nanotechnology     Open Access   (Followers: 28)
Advances in Operations Research     Open Access   (Followers: 11)
Advances in OptoElectronics     Open Access   (Followers: 5)
Advances in Physics Theories and Applications     Open Access   (Followers: 12)
Advances in Polymer Science     Hybrid Journal   (Followers: 41)
Advances in Porous Media     Full-text available via subscription   (Followers: 4)
Advances in Remote Sensing     Open Access   (Followers: 37)
Advances in Science and Research (ASR)     Open Access   (Followers: 6)
Aerobiologia     Hybrid Journal   (Followers: 1)
African Journal of Science, Technology, Innovation and Development     Hybrid Journal   (Followers: 4)
AIChE Journal     Hybrid Journal   (Followers: 30)
Ain Shams Engineering Journal     Open Access   (Followers: 5)
Akademik Platform Mühendislik ve Fen Bilimleri Dergisi     Open Access  
Alexandria Engineering Journal     Open Access   (Followers: 1)
AMB Express     Open Access   (Followers: 1)
American Journal of Applied Sciences     Open Access   (Followers: 28)
American Journal of Engineering and Applied Sciences     Open Access   (Followers: 11)
American Journal of Engineering Education     Open Access   (Followers: 9)
American Journal of Environmental Engineering     Open Access   (Followers: 16)
American Journal of Industrial and Business Management     Open Access   (Followers: 23)
Analele Universitatii Ovidius Constanta - Seria Chimie     Open Access  
Annals of Combinatorics     Hybrid Journal   (Followers: 3)
Annals of Pure and Applied Logic     Open Access   (Followers: 2)
Annals of Regional Science     Hybrid Journal   (Followers: 7)
Annals of Science     Hybrid Journal   (Followers: 7)
Applicable Algebra in Engineering, Communication and Computing     Hybrid Journal   (Followers: 2)
Applicable Analysis: An International Journal     Hybrid Journal   (Followers: 1)
Applied Catalysis A: General     Hybrid Journal   (Followers: 6)
Applied Catalysis B: Environmental     Hybrid Journal   (Followers: 12)
Applied Clay Science     Hybrid Journal   (Followers: 5)
Applied Computational Intelligence and Soft Computing     Open Access   (Followers: 12)
Applied Magnetic Resonance     Hybrid Journal   (Followers: 4)
Applied Nanoscience     Open Access   (Followers: 7)
Applied Network Science     Open Access  
Applied Numerical Mathematics     Hybrid Journal   (Followers: 5)
Applied Physics Research     Open Access   (Followers: 3)
Applied Sciences     Open Access   (Followers: 2)
Applied Spatial Analysis and Policy     Hybrid Journal   (Followers: 4)
Arabian Journal for Science and Engineering     Hybrid Journal   (Followers: 5)
Archives of Computational Methods in Engineering     Hybrid Journal   (Followers: 4)
Archives of Foundry Engineering     Open Access  
Archives of Thermodynamics     Open Access   (Followers: 7)
Arid Zone Journal of Engineering, Technology and Environment     Open Access   (Followers: 2)
Arkiv för Matematik     Hybrid Journal   (Followers: 1)
ASEE Prism     Full-text available via subscription   (Followers: 3)
Asian Engineering Review     Open Access  
Asian Journal of Applied Science and Engineering     Open Access   (Followers: 1)
Asian Journal of Applied Sciences     Open Access   (Followers: 2)
Asian Journal of Biotechnology     Open Access   (Followers: 8)
Asian Journal of Control     Hybrid Journal  
Asian Journal of Current Engineering & Maths     Open Access  
Asian Journal of Technology Innovation     Hybrid Journal   (Followers: 8)
Assembly Automation     Hybrid Journal   (Followers: 2)
at - Automatisierungstechnik     Hybrid Journal   (Followers: 1)
ATZagenda     Hybrid Journal  
ATZextra worldwide     Hybrid Journal  
Australasian Physical & Engineering Sciences in Medicine     Hybrid Journal   (Followers: 1)
Australian Journal of Multi-Disciplinary Engineering     Full-text available via subscription   (Followers: 2)
Autonomous Mental Development, IEEE Transactions on     Hybrid Journal   (Followers: 8)
Avances en Ciencias e Ingeniería     Open Access  
Balkan Region Conference on Engineering and Business Education     Open Access   (Followers: 1)
Bangladesh Journal of Scientific and Industrial Research     Open Access  
Basin Research     Hybrid Journal   (Followers: 5)
Batteries     Open Access   (Followers: 4)
Bautechnik     Hybrid Journal   (Followers: 1)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 23)
Beni-Suef University Journal of Basic and Applied Sciences     Open Access   (Followers: 4)
BER : Manufacturing Survey : Full Survey     Full-text available via subscription   (Followers: 2)
BER : Motor Trade Survey     Full-text available via subscription   (Followers: 1)
BER : Retail Sector Survey     Full-text available via subscription   (Followers: 2)
BER : Retail Survey : Full Survey     Full-text available via subscription   (Followers: 2)
BER : Survey of Business Conditions in Manufacturing : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Retail : An Executive Summary     Full-text available via subscription   (Followers: 3)
Bharatiya Vaigyanik evam Audyogik Anusandhan Patrika (BVAAP)     Open Access   (Followers: 1)
Biofuels Engineering     Open Access  
Biointerphases     Open Access   (Followers: 1)
Biomaterials Science     Full-text available via subscription   (Followers: 9)
Biomedical Engineering     Hybrid Journal   (Followers: 16)
Biomedical Engineering and Computational Biology     Open Access   (Followers: 13)
Biomedical Engineering Letters     Hybrid Journal   (Followers: 5)
Biomedical Engineering, IEEE Reviews in     Full-text available via subscription   (Followers: 17)
Biomedical Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 32)
Biomedical Engineering: Applications, Basis and Communications     Hybrid Journal   (Followers: 5)
Biomedical Microdevices     Hybrid Journal   (Followers: 8)
Biomedical Science and Engineering     Open Access   (Followers: 3)
Biomedizinische Technik - Biomedical Engineering     Hybrid Journal  
Biomicrofluidics     Open Access   (Followers: 4)
BioNanoMaterials     Hybrid Journal   (Followers: 2)
Biotechnology Progress     Hybrid Journal   (Followers: 39)
Boletin Cientifico Tecnico INIMET     Open Access  
Botswana Journal of Technology     Full-text available via subscription  
Boundary Value Problems     Open Access   (Followers: 1)
Brazilian Journal of Science and Technology     Open Access   (Followers: 2)
Broadcasting, IEEE Transactions on     Hybrid Journal   (Followers: 10)
Bulletin of Canadian Petroleum Geology     Full-text available via subscription   (Followers: 14)
Bulletin of Engineering Geology and the Environment     Hybrid Journal   (Followers: 3)
Bulletin of the Crimean Astrophysical Observatory     Hybrid Journal  
Cahiers, Droit, Sciences et Technologies     Open Access  
Calphad     Hybrid Journal  
Canadian Geotechnical Journal     Hybrid Journal   (Followers: 14)
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 41)
Case Studies in Engineering Failure Analysis     Open Access   (Followers: 8)
Case Studies in Thermal Engineering     Open Access   (Followers: 3)
Catalysis Communications     Hybrid Journal   (Followers: 6)
Catalysis Letters     Hybrid Journal   (Followers: 2)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 8)
Catalysis Science and Technology     Free   (Followers: 6)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysis Today     Hybrid Journal   (Followers: 7)
CEAS Space Journal     Hybrid Journal  
Cellular and Molecular Neurobiology     Hybrid Journal   (Followers: 3)
Central European Journal of Engineering     Hybrid Journal   (Followers: 1)
CFD Letters     Open Access   (Followers: 6)
Chaos : An Interdisciplinary Journal of Nonlinear Science     Hybrid Journal   (Followers: 2)
Chaos, Solitons & Fractals     Hybrid Journal   (Followers: 3)
Chinese Journal of Catalysis     Full-text available via subscription   (Followers: 2)
Chinese Journal of Engineering     Open Access   (Followers: 2)
Chinese Science Bulletin     Open Access   (Followers: 1)
Ciencia e Ingenieria Neogranadina     Open Access  
Ciencia en su PC     Open Access   (Followers: 1)
Ciencias Holguin     Open Access   (Followers: 1)
CienciaUAT     Open Access  
Cientifica     Open Access  
CIRP Annals - Manufacturing Technology     Full-text available via subscription   (Followers: 11)
CIRP Journal of Manufacturing Science and Technology     Full-text available via subscription   (Followers: 14)
City, Culture and Society     Hybrid Journal   (Followers: 21)
Clay Minerals     Full-text available via subscription   (Followers: 10)
Clean Air Journal     Full-text available via subscription   (Followers: 2)
Coal Science and Technology     Full-text available via subscription   (Followers: 3)
Coastal Engineering     Hybrid Journal   (Followers: 11)
Coastal Engineering Journal     Hybrid Journal   (Followers: 5)
Coatings     Open Access   (Followers: 3)
Cogent Engineering     Open Access   (Followers: 2)
Cognitive Computation     Hybrid Journal   (Followers: 4)
Color Research & Application     Hybrid Journal   (Followers: 1)
COMBINATORICA     Hybrid Journal  
Combustion Theory and Modelling     Hybrid Journal   (Followers: 13)
Combustion, Explosion, and Shock Waves     Hybrid Journal   (Followers: 13)
Communications Engineer     Hybrid Journal   (Followers: 1)
Communications in Numerical Methods in Engineering     Hybrid Journal   (Followers: 2)
Components, Packaging and Manufacturing Technology, IEEE Transactions on     Hybrid Journal   (Followers: 26)
Composite Interfaces     Hybrid Journal   (Followers: 6)
Composite Structures     Hybrid Journal   (Followers: 254)
Composites Part A : Applied Science and Manufacturing     Hybrid Journal   (Followers: 179)
Composites Part B : Engineering     Hybrid Journal   (Followers: 230)
Composites Science and Technology     Hybrid Journal   (Followers: 171)
Comptes Rendus Mécanique     Full-text available via subscription   (Followers: 2)
Computation     Open Access  
Computational Geosciences     Hybrid Journal   (Followers: 14)
Computational Optimization and Applications     Hybrid Journal   (Followers: 7)
Computational Science and Discovery     Full-text available via subscription   (Followers: 2)
Computer Applications in Engineering Education     Hybrid Journal   (Followers: 6)
Computer Science and Engineering     Open Access   (Followers: 17)
Computers & Geosciences     Hybrid Journal   (Followers: 28)
Computers & Mathematics with Applications     Full-text available via subscription   (Followers: 5)
Computers and Electronics in Agriculture     Hybrid Journal   (Followers: 4)
Computers and Geotechnics     Hybrid Journal   (Followers: 10)
Computing and Visualization in Science     Hybrid Journal   (Followers: 5)
Computing in Science & Engineering     Full-text available via subscription   (Followers: 30)
Conciencia Tecnologica     Open Access  
Concurrent Engineering     Hybrid Journal   (Followers: 3)
Continuum Mechanics and Thermodynamics     Hybrid Journal   (Followers: 6)
Control and Dynamic Systems     Full-text available via subscription   (Followers: 8)
Control Engineering Practice     Hybrid Journal   (Followers: 42)
Control Theory and Informatics     Open Access   (Followers: 7)
Corrosion Science     Hybrid Journal   (Followers: 25)
CT&F Ciencia, Tecnologia y Futuro     Open Access  
CTheory     Open Access  

        1 2 3 4 5 6 7 | Last

Journal Cover Applied Sciences
  [SJR: 0.178]   [H-I: 9]   [2 followers]  Follow
    
  This is an Open Access Journal Open Access journal
   ISSN (Online) 2076-3417
   Published by MDPI Homepage  [151 journals]
  • Applied Sciences, Vol. 7, Pages 748: Needle Segmentation in Volumetric
           Optical Coherence Tomography Images for Ophthalmic Microsurgery

    • Authors: Mingchuan Zhou, Hessam Roodaki, Abouzar Eslami, Guang Chen, Kai Huang, Mathias Maier, Chris Lohmann, Alois Knoll, Mohammad Nasseri
      First page: 748
      Abstract: Needle segmentation is a fundamental step for needle reconstruction and image-guided surgery. Although there has been success stories in needle segmentation for non-microsurgeries, the methods cannot be directly extended to ophthalmic surgery due to the challenges bounded to required spatial resolution. As the ophthalmic surgery is performed by finer and smaller surgical instruments in micro-structural anatomies, specifically in retinal domains, difficulties are raised for delicate operation and sensitive perception. To address these challenges, in this paper we investigate needle segmentation in ophthalmic operation on 60 Optical Coherence Tomography (OCT) cubes captured during needle injection surgeries on ex-vivo pig eyes. Furthermore, we developed two different approaches, a conventional method based on morphological features (MF) and a specifically designed full convolution neural networks (FCN) method, moreover, we evaluate them on the benchmark for needle segmentation in the volumetric OCT images. The experimental results show that FCN method has a better segmentation performance based on four evaluation metrics while MF method has a short inference time, which provides valuable reference for future works.
      Citation: Applied Sciences
      PubDate: 2017-07-25
      DOI: 10.3390/app7080748
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 751: Prediction of Ultimate Strain and
           Strength of FRP-Confined Concrete Cylinders Using Soft Computing Methods

    • Authors: Iman Mansouri, Ozgur Kisi, Pedram Sadeghian, Chang-Hwan Lee, Jong Hu
      First page: 751
      Abstract: This paper investigates the effectiveness of four different soft computing methods, namely radial basis neural network (RBNN), adaptive neuro fuzzy inference system (ANFIS) with subtractive clustering (ANFIS-SC), ANFIS with fuzzy c-means clustering (ANFIS-FCM) and M5 model tree (M5Tree), for predicting the ultimate strength and strain of concrete cylinders confined with fiber-reinforced polymer (FRP) sheets. The models were compared according to the root mean square error (RMSE), mean absolute relative error (MARE) and determination coefficient (R2) criteria. Similar accuracy was obtained by RBNN and ANFIS-FCM, and they provided better estimates in modeling ultimate strength of confined concrete. The ANFIS-SC, however, performed slightly better than the RBNN and ANFIS-FCM in estimating ultimate strain of confined concrete, and M5Tree provided the worst strength and strain estimates. Finally, the effects of strain ratio and the confinement stiffness ratio on strength and strain were investigated, and the confinement stiffness ratio was shown to be more effective.
      Citation: Applied Sciences
      PubDate: 2017-07-25
      DOI: 10.3390/app7080751
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 753: Automated Diatom Classification (Part
           A): Handcrafted Feature Approaches

    • Authors: Gloria Bueno, Oscar Deniz, Anibal Pedraza, Jesús Ruiz-Santaquiteria, Jesús Salido, Gabriel Cristóbal, María Borrego-Ramos, Saúl Blanco
      First page: 753
      Abstract: This paper deals with automatic taxa identification based on machine learning methods. The aim is therefore to automatically classify diatoms, in terms of pattern recognition terminology. Diatoms are a kind of algae microorganism with high biodiversity at the species level, which are useful for water quality assessment. The most relevant features for diatom description and classification have been selected using an extensive dataset of 80 taxa with a minimum of 100 samples/taxon augmented to 300 samples/taxon. In addition to published morphological, statistical and textural descriptors, a new textural descriptor, Local Binary Patterns (LBP), to characterize the diatom’s valves, and a log Gabor implementation not tested before for this purpose are introduced in this paper. Results show an overall accuracy of 98.11% using bagging decision trees and combinations of descriptors. Finally, some phycological features of diatoms that are still difficult to integrate in computer systems are discussed for future work.
      Citation: Applied Sciences
      PubDate: 2017-07-25
      DOI: 10.3390/app7080753
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 754: Modified Chaos Particle Swarm
           Optimization-Based Optimized Operation Model for Stand-Alone CCHP
           Microgrid

    • Authors: Fei Wang, Lidong Zhou, Bo Wang, Zheng Wang, Miadreza Shafie-khah, João Catalão
      First page: 754
      Abstract: The optimized dispatch of different distributed generations (DGs) in stand-alone microgrid (MG) is of great significance to the operation’s reliability and economy, especially for energy crisis and environmental pollution. Based on controllable load (CL) and combined cooling-heating-power (CCHP) model of micro-gas turbine (MT), a multi-objective optimization model with relevant constraints to optimize the generation cost, load cut compensation and environmental benefit is proposed in this paper. The MG studied in this paper consists of photovoltaic (PV), wind turbine (WT), fuel cell (FC), diesel engine (DE), MT and energy storage (ES). Four typical scenarios were designed according to different day types (work day or weekend) and weather conditions (sunny or rainy) in view of the uncertainty of renewable energy in variable situations and load fluctuation. A modified dispatch strategy for CCHP is presented to further improve the operation economy without reducing the consumers’ comfort feeling. Chaotic optimization and elite retention strategy are introduced into basic particle swarm optimization (PSO) to propose modified chaos particle swarm optimization (MCPSO) whose search capability and convergence speed are improved greatly. Simulation results validate the correctness of the proposed model and the effectiveness of MCPSO algorithm in the optimized operation application of stand-alone MG.
      Citation: Applied Sciences
      PubDate: 2017-07-25
      DOI: 10.3390/app7080754
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 755: Development of a Magnetostrictive
           FeNi Coated Surface Acoustic Wave Current Sensor

    • Authors: Jie Tong, Yana Jia, Wen Wang, Yang Wang, Shiyue Wang, Xinlu Liu, Yuqing Lei
      First page: 755
      Abstract: A magnetostrictive FeNi-coated surface acoustic wave (SAW)-based current sensor was proposed in this work. The weak remanence and hysteresis effect of the FeNi itself contributes to suppress the asymmetry in sensor response at increasing and decreasing current. The sensor response was simulated by solving the coupled electromechanical field equation in layered structure considering the magnetostrictive effect and an approach of effective dielectric constant. The effects from the aspect ratio and thickness of the FeNi film on sensor response were analyzed to determine the optimal design parameters. Differential oscillation structure was used to form the sensor, in which, the FeNi thin film was deposited along the SAW propagation of the sensor chip by using RF magnetron sputtering. The magnetostrictive effect of the FeNi coating induced by the magnetic loading generates the perturbation in SAW velocity, and corresponding oscillation frequency. High sensitivity of 10.7 KHz/A, good linearity and repeatability, lower hysteresis error of 0.97% were obtained from the developed prototype 150 MHz SAW FeNi coated current sensor.
      Citation: Applied Sciences
      PubDate: 2017-07-25
      DOI: 10.3390/app7080755
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 756: Optimization of a Culture Medium
           Using the Taguchi Approach for the Production of Microorganisms Active in
           Odorous Compound Removal

    • Authors: Krzysztof Makowski, Katarzyna Matusiak, Sebastian Borowski, Jakub Bielnicki, Alicja Tarazewicz, Marta Maroszyńska, Martyna Leszczewicz, Szymon Powałowski, Beata Gutarowska
      First page: 756
      Abstract: The aim of this work was to develop the composition of a medium for the cultivation of six microbial strains forming a deodorizing consortium: Pseudomonas fluorescens, Enterococcus faecium, Bacillus subtilis, Bacillus megaterium, Leuconostoc mesenteroides and Lactobacillus plantarum. The study focused on the optimization of a highly efficient culture medium composed of readily available components of plant origin to maximize microbial biomass yields, and to create a less expensive alternative to the commercial Tryptic Soy Broth medium (TSB). After preliminary efficiency screening of all tested media components, we selected four substrates for further optimization—soy protein concentrate (SPC), glucose or sucrose, and phosphate salts. The final concentrations of all components were fine-tuned using the Taguchi design for experiments according to an L9 array. Taguchi optimization led to formulation of a culture medium, which was approximately 5 times cheaper than TSB (depending on the components used). Consequently, microbial biomass yields were improved by up to 15-fold (1564%), depending on the strain. The results obtained in the laboratory experiments were then confirmed in pilot- (42 L) and industrial- (300 L) scale fermentation. Our results show that this method of using a parallel culture microbioreactor with the Taguchi approach can be recommended for optimization of culture media based on substrates of plant origin.
      Citation: Applied Sciences
      PubDate: 2017-07-25
      DOI: 10.3390/app7080756
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 757: A Real Model of a Micro-Grid to
           Improve Network Stability

    • Authors: Petr Marcon, Zoltan Szabo, Ivo Vesely, Frantisek Zezulka, Ondrej Sajdl, Zdenek Roubal, Premysl Dohnal
      First page: 757
      Abstract: This paper discusses the smart energy model of a smart grid using a significant share of renewable energy sources combined with intelligent control that processes information from a smart metering subsystem. An algorithm to manage the microgrid via the demand-response strategy is proposed, accentuating the requirement that the total volume of energy produced from renewable sources is consumed. Thus, the system utilizes the maximum of renewable sources to reduce CO2 emissions. Another major benefit provided by the algorithm lies in applying the current weather forecast to predict the amount of energy in the grid; electricity can then be transferred between the local and the main backup batteries within the grid, and this option enables the control elements to prepare for a condition yet to occur. Individual parts of the grid are described in this research report together with the results provided by the relevant algorithm.
      Citation: Applied Sciences
      PubDate: 2017-07-26
      DOI: 10.3390/app7080757
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 758: Performance Analysis and Design
           Strategy for a Second-Order, Fixed-Gain, Position-Velocity-Measured
           (α-β-η-θ) Tracking Filter

    • Authors: Kenshi Saho, Masao Masugi
      First page: 758
      Abstract: We present a strategy for designing an α - β - η - θ filter, a fixed-gain moving-object tracking filter using position and velocity measurements. First, performance indices and stability conditions for the filter are analytically derived. Then, an optimal gain design strategy using these results is proposed and its relationship to the position-velocity-measured (PVM) Kalman filter is shown. Numerical analyses demonstrate the effectiveness of the proposed strategy, as well as a performance improvement over the traditional position-only-measured α - β filter. Moreover, we apply an α - β - η - θ filter designed using this strategy to ultra-wideband Doppler radar tracking in numerical simulations. We verify that the proposed strategy can easily design the gains for an α - β - η - θ filter based on the performance of the ultra-wideband Doppler radar and a rough approximation of the target’s acceleration. Moreover, its effectiveness in predicting the steady state performance in designing the position-velocity-measured Kalman filter is also demonstrated.
      Citation: Applied Sciences
      PubDate: 2017-07-26
      DOI: 10.3390/app7080758
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 759: A Novel Hybrid Approach to Deal with
           DVL Malfunctions for Underwater Integrated Navigation Systems

    • Authors: Yixian Zhu, Xianghong Cheng, Jie Hu, Ling Zhou, Jinbo Fu
      First page: 759
      Abstract: As a common device for underwater integrated navigation systems, Doppler velocity log (DVL) has the risk of malfunction. To improve the reliability of navigation systems, a hybrid approach is presented to forecast the measurements of the DVL while it malfunctions. The approach employs partial least squares regression (PLSR) coupled with support vector regression (SVR) to build a hybrid predictor. As the current and past calculating velocities of strapdown inertial navigation system (SINS) are taken as the predictor’s inputs, PLSR is applied to cope with the situation where there exists intense relativity among independent variables. Since PLSR is a linear regression, SVR is used to predict the residual components of the PLSR prediction to improve the accuracy. When the DVL works well, the hybrid predictor is trained online as a backup, whereas during malfunctions, the predictor offers the estimation of the DVL measurements for information fusion. The performance of the proposed approach is verified with simulations based on SINS/DVL/MCP/pressure sensor (PS) integrated navigation system. The comparison results indicate that the PLSR-SVR hybrid predictor can correctly provide the estimated DVL measurements and effectively extend the tolerance time on DVL malfunctions, thereby improving the navigation accuracy and reliability.
      Citation: Applied Sciences
      PubDate: 2017-07-26
      DOI: 10.3390/app7080759
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 760: The Static Frictional Behaviors of
           Rubber for Pipe-Laying Operation

    • Authors: Yong-Jie Zhou, De-Guo Wang, Yan-Bao Guo, Shu-Hai Liu
      First page: 760
      Abstract: Experimental research is carried out to reveal the static frictional behaviors of rubber pipe contact systems. This research is motivated by deep water pipe-laying operations where rubber blocks are used to clamp the pipe to supply sufficient static friction. Within this context, a friction testing instrument has been designed to mimic a situation of the beginning of the pipe-laying installation. Using this instrument, the maximum static friction forces (F) of a rubber pipe contact system are tested. The results show that the ultimate values of the static frictions fluctuate due to the increasing rate of the tangential load (FT). The evolution of contact between rubber and polymethyl methacrylate (PMMA) pipe is observed to identify the formation and propagation of the folds within the apparent contact area. In addition, it is confirmed that the evolution of contact is influenced by the folds and creep of the rubber surface. The creep deformation takes primary effect in accelerating the separation of the interfaces of contact during relative high normal loads (20, 30, 40 N) and low increasing rate of FT; whereas for all of the testing normal loads (10–40 N), the propagation of the folds release the energy which is stored in the interface of rubber when the increasing rate of FT is high. Therefore, the fluctuation of the maximum static friction of the contact system can be regarded as a consequence of interaction of the creep and folds. Furthermore, the instability of the coefficient of static friction in this test has been examined, and it indicated that the creep and folds could affect the static friction distinctly within a certain range of a normal load. This research is beneficial for arranging appropriate normal loads and laying speeds to avoid pipes slipping during a pipe-laying operation.
      Citation: Applied Sciences
      PubDate: 2017-07-26
      DOI: 10.3390/app7080760
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 761: Non-Local Effects in Brillouin
           Optical Time-Domain Analysis Sensors

    • Authors: Haritz Iribas, Javier Urricelqui, Juan Mompó, Jon Mariñelarena, Alayn Loayssa
      First page: 761
      Abstract: Brillouin optical time-domain analysis (BOTDA) sensors have great potential to provide distributed measurements of temperature and strain over large structures with high spatial resolution and measurement precision. However, their performance ultimately depends on the amount of probe and pump pulse power that can be injected into the sensing fiber, which determines the signal-to-noise ratio of the detected measurement signal. The probe wave power is constrained by the generation of noise induced by spontaneous Brillouin scattering and at lower power by the so-called non-local effects. In this work, we focus on the latter. We review the physical origins of non-local effects and analyze the performance impairments that they bring. In addition, we discuss the different methods that have been proposed to counteract these effects comparing their relative merits and ultimate performance. Particularly, we focus on a technique that we have devised to compensate non-local effects which is based on introducing an optical frequency modulation or dithering to the probe wave. This method is shown to provide a comprehensive solution to most of the impairments associated with non-local effects and also to enable some side benefits, such as amplification of the pump pulses to compensate the attenuation of the fiber.
      Citation: Applied Sciences
      PubDate: 2017-07-27
      DOI: 10.3390/app7080761
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 762: A Tuning Method for Diatom
           Segmentation Techniques

    • Authors: Oswaldo Rojas Camacho, Manuel Forero, José Menéndez
      First page: 762
      Abstract: Phytoplankton such as diatoms or desmids are useful for monitoring water quality. Manual image analysis is impractical due to the huge diversity of this group of microalgae and its great morphological plasticity, hence the importance of automating the analysis procedure. High-resolution images of phytoplankton cells can now be acquired by digital microscopes, which facilitate automating the analysis and identification process of specimens. Therefore, new systems of image analysis are potentially advantageous compared to manual methods of counting for solution identification. Segmentation is an important step in the analysis of phytoplankton images. Many standard techniques like thresholding and edge detection are employed in the segmentation of diatoms and other phytoplankton, which are crucial organisms in microscopy images. However, in general, they require several parameters to be fixed beforehand by the user in order to get the best results. This process is usually done by comparing results and looking for the best parameters. To automatize this process, we propose an automatic tuning method to find the optimal parameters in an iterative procedure, called Parametric Segmentation Tuning (PST). This technique compares successive segmentation results, choosing the ones that gets the maximal similarity. In this paper, tuning is formulated as an optimization problem using a similarity function within the solution space. This space consists of the set of binary images that are generated by the segmentation technique to be tuned, where these binary images are seen as a function of the original images and the segmentation parameters. The PST technique was tested with two of the most popular techniques employed to segment phytoplankton images: the Canny edge detection and a binarisation method. The results of the thresholding technique were validated by comparing them to those of the Otsu method and the Canny method with a ground truth. They show that PST is effective to find the best parameters.
      Citation: Applied Sciences
      PubDate: 2017-07-27
      DOI: 10.3390/app7080762
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 763: Evaluation of Mechanical Properties
           of Recycled Material for Utilization in Asphalt Mixtures

    • Authors: Farzaneh Tahmoorian, Bijan Samali, Vivian Tam, John Yeaman
      First page: 763
      Abstract: With an expanding world, the demand for extensive road networks is increasing. As natural resources become scarce, the necessity of finding alternative resources has led to the idea of applying recycled material to pavement construction including asphalt pavements. Amongst all asphalt components, aggregate constitutes the largest part of asphalt mixtures. Therefore, the utilization of recycled material for aggregate will represent an important opportunity to save virgin material and divert material away from landfills. Because of the large amount of construction waste generation around the world, using recycled construction aggregate (RCA) in asphalt mixtures appears to be an effective utilization of RCA. However, as aggregate plays an important role in the final performance of the asphalt mixture, an understanding of their properties is essential in designing an asphalt mixture. Therefore, in this research, the properties of RCA have been evaluated through laboratory investigations. Based on the test results, it is required that combination of RCA with some other targeted waste materials be considered in asphalt mixture. This paper presents the results of an experimental study to evaluate the RCA properties as an alternative for virgin aggregate in asphalt mixture under different percentages and combination with other aggregates, such as reclaimed asphalt pavement (RAP) and basalt.
      Citation: Applied Sciences
      PubDate: 2017-07-27
      DOI: 10.3390/app7080763
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 764: 3D Model Identification Using
           Weighted Implicit Shape Representation and Panoramic View

    • Authors: Xun Jin, Jongweon Kim
      First page: 764
      Abstract: In this paper, we propose a 3 dimensional (3D) model identification method based on weighted implicit shape representation (WISR) and panoramic view. The WISR is used for 3D shape normalization. The 3D shape normalization method normalizes a 3D model by scaling, translation, and rotation with respect to the scale factor, center, and principal axes. The major advantage of the WISR is reduction of the influences caused by shape deformation and partial removal. The well-known scale-invariant feature transform descriptors are extracted from the panoramic view of the 3D model for feature matching. The panoramic view is a range image obtained by projecting a 3D model to the surface of a cylinder which is parallel to a principal axis determined by the 3D shape normalization. Because of using only one range image, the proposed method can provide small size of features and fast matching speed. The precision of the identification is 92% with 1200 models that consist of 24 deformed versions of 50 classes. The average feature size and matching time are 4.1 KB and 1.9 s.
      Citation: Applied Sciences
      PubDate: 2017-07-27
      DOI: 10.3390/app7080764
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 765: The Performance and Fouling Control
           of Submerged Hollow Fiber (HF) Systems: A Review

    • Authors: Ebrahim Akhondi, Farhad Zamani, Keng Tng, Gregory Leslie, William Krantz, Anthony Fane, Jia Chew
      First page: 765
      Abstract: The submerged membrane filtration concept is well-established for low-pressure microfiltration (MF) and ultrafiltration (UF) applications in the water industry, and has become a mainstream technology for surface-water treatment, pretreatment prior to reverse osmosis (RO), and membrane bioreactors (MBRs). Compared to submerged flat sheet (FS) membranes, submerged hollow fiber (HF) membranes are more common due to their advantages of higher packing density, the ability to induce movement by mechanisms such as bubbling, and the feasibility of backwashing. In view of the importance of submerged HF processes, this review aims to provide a comprehensive landscape of the current state-of-the-art systems, to serve as a guide for further improvements in submerged HF membranes and their applications. The topics covered include recent developments in submerged hollow fiber membrane systems, the challenges and developments in fouling-control methods, and treatment protocols for membrane permeability recovery. The highlighted research opportunities include optimizing the various means to manipulate the hydrodynamics for fouling mitigation, developing online monitoring devices, and extending the submerged HF concept beyond filtration.
      Citation: Applied Sciences
      PubDate: 2017-07-28
      DOI: 10.3390/app7080765
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 766: A Study on the Stall Detection of an
           Axial Compressor through Pressure Analysis

    • Authors: Haoying Chen, Fengyong Sun, Haibo Zhang, Wei Luo
      First page: 766
      Abstract: In order to research the inherent working laws of compressors nearing stall state, a series of compressor experiments are conducted. With the help of fast Fourier transform, the amplitude–frequency characteristics of pressures at the compressor inlet, outlet and blade tip region outlet are analyzed. Meanwhile, devices imitating inlet distortion were applied in the compressor inlet distortion disturbance. The experimental results indicated that compressor blade tip region pressure showed a better performance than the compressor’s inlet and outlet pressures in regards to describing compressor characteristics. What’s more, compressor inlet distortion always disturbed the compressor pressure characteristics. Whether with inlet distortion or not, the pressure characteristics of pressure periodicity and amplitude frequency could always be maintained in compressor blade tip pressure. For the sake of compressor real-time stall detection application, a compressor stall detection algorithm is proposed to calculate the compressor pressure correlation coefficient. The algorithm also showed a good monotonicity in describing the relationship between the compressor surge margin and the pressure correlation coefficient.
      Citation: Applied Sciences
      PubDate: 2017-07-28
      DOI: 10.3390/app7080766
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 767: Chinese Medical Question Answer
           Matching Using End-to-End Character-Level Multi-Scale CNNs

    • Authors: Sheng Zhang, Xin Zhang, Hui Wang, Jiajun Cheng, Pei Li, Zhaoyun Ding
      First page: 767
      Abstract: This paper focuses mainly on the problem of Chinese medical question answer matching, which is arguably more challenging than open-domain question answer matching in English due to the combination of its domain-restricted nature and the language-specific features of Chinese. We present an end-to-end character-level multi-scale convolutional neural framework in which character embeddings instead of word embeddings are used to avoid Chinese word segmentation in text preprocessing, and multi-scale convolutional neural networks (CNNs) are then introduced to extract contextual information from either question or answer sentences over different scales. The proposed framework can be trained with minimal human supervision and does not require any handcrafted features, rule-based patterns, or external resources. To validate our framework, we create a new text corpus, named cMedQA, by harvesting questions and answers from an online Chinese health and wellness community. The experimental results on the cMedQA dataset show that our framework significantly outperforms several strong baselines, and achieves an improvement of top-1 accuracy by up to 19%.
      Citation: Applied Sciences
      PubDate: 2017-07-28
      DOI: 10.3390/app7080767
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 768: Special Issue on Polarimetric SAR
           Techniques and Applications

    • Authors: Carlos Lopez-Martinez, Juan Lopez-Sanchez
      First page: 768
      Abstract: Synthetic Aperture Radar (SAR) polarimetry is an active and fruitful field of research in Earth observation. [...]
      Citation: Applied Sciences
      PubDate: 2017-07-28
      DOI: 10.3390/app7080768
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 769: The Synchrosqueezing Algorithm Based
           on Generalized S-transform for High-Precision Time-Frequency Analysis

    • Authors: Hui Chen, Lingqi Lu, Dan Xu, Jiaxing Kang, Xuping Chen
      First page: 769
      Abstract: In this paper, a new time-frequency analysis method—Synchrosqueezing Generalized S-transform (SSGST)—is proposed to meet the needs of high-resolution seismic signal processing and interpretation. The basic wavelet of the generalized S-transform (GST) in the paper is a modulated harmonic wave with four undetermined parameters that can be constructed by adjusting the four parameters to make the GST more suitable for seismic signals processing. The SSGST method squeezes and reconstructs the complex coefficient spectra of GST results along the frequency direction so that the energy distributions on the time-frequency spectra are concentrated around the real instantaneous frequency of the signal; thus, the time-frequency resolution can be improved. Based on mathematical theory, the basic principle of the new transformation method is given, and the mathematical expressions of the positive transformation and lossless inverse transformation of the method are strictly deduced. The experimental results of numerical signals illustrate that the proposed method can correctly decompose signals with different spectral characteristics into a high time-frequency resolution spectrum and can recovery the original signal from the time-frequency spectrum with satisfying reconstructing accuracy. Application on field seismic data shows the superiority of the new method in seismic time-frequency analysis for hydrocarbon detection.
      Citation: Applied Sciences
      PubDate: 2017-07-28
      DOI: 10.3390/app7080769
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 770: Using a Molecular Dynamics Simulation
           to Investigate Asphalt Nano-Cracking under External Loading Conditions

    • Authors: Yue Hou, Linbing Wang, Dawei Wang, Xin Qu, Jiangfeng Wu
      First page: 770
      Abstract: Recent research shows that macro-scale cracking in asphalt binder may originate from its intrinsic defects at the nano-scale. In this paper, a molecular dynamics (MD) simulation was conducted to evaluate the nucleation of natural defects in asphalt. The asphalt microstructure was modeled using an ensemble of three different types of molecules to represent a constituent species: asphaltenes, naphthene aromatics and saturates, where the weight proportion of 20:60:20 was used to create an asphalt-like ensemble of molecules. Tension force was then applied on the molecular boundaries to study the crack initiation and propagation. It was discovered that the natural distribution of atoms at microscale would affect the intrinsic defects in asphalt and further influence crack initiation and propagation in asphalt.
      Citation: Applied Sciences
      PubDate: 2017-07-28
      DOI: 10.3390/app7080770
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 771: A Biomechanical Study for Developing
           Wearable-Sensor System to Prevent Hip Fractures among Seniors

    • Authors: Gongbing Shan, Xiang Zhang, Mingliang Meng, Brandie Wilde
      First page: 771
      Abstract: As the population ages, falls are becoming a major health problem, not only for those with some degree of balance or mobility impairment, but also among healthy active seniors. Previous studies suggest that the degradation of human sensorimotor function related to age contributes to falls. Hip bones are among the most frequently fractured body parts resulting from falls. Hip fractures are a frequent cause of early death, functional dependence, and high medical care costs. The current prevention method is to use hip protectors. Unfortunately, it often fails to do so because the pocket containing the pad can move away from the area during falls. Additionally, some seniors refuse to use hip protectors because they find them constraining. Hence, a new protector that is only activated during a fall is much desired. The current study explored the possibility via biomechanical analyses for building a wearable sensor system that triggers a mini-airbag system during a fall, i.e., the air-pad is only present for protection when a fall occurs. The results have revealed that two sensors placed on the left and right shoulder would be best for a detection of any-direction fall and could be applied for building a wearable sensor system for prevention of hip fractures resulting from falls.
      Citation: Applied Sciences
      PubDate: 2017-07-30
      DOI: 10.3390/app7080771
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 772: Monitoring of Land-Surface
           Deformation in the Karamay Oilfield, Xinjiang, China, Using SAR
           Interferometry

    • Authors: Yusupujiang Aimaiti, Fumio Yamazaki, Wen Liu, Alimujiang Kasimu
      First page: 772
      Abstract: Synthetic Aperture Radar (SAR) interferometry is a technique that provides high-resolution measurements of the ground displacement associated with various geophysical processes. To investigate the land-surface deformation in Karamay, a typical oil-producing city in the Xinjiang Uyghur Autonomous Region, China, Advanced Land Observing Satellite (ALOS) Phased Array L-band Synthetic Aperture Radar (PALSAR) data were acquired for the period from 2007 to 2009, and a two-pass differential SAR interferometry (D-InSAR) process was applied. The experimental results showed that two sites in the north-eastern part of the city exhibit a clear indication of land deformation. For a further evaluation of the D-InSAR result, the Persistent Scatterer (PS) and Small Baseline Subset (SBAS)-InSAR techniques were applied for 21 time series Environmental Satellite (ENVISAT) C-band Advanced Synthetic Aperture Radar (ASAR) data from 2003 to 2010. The comparison between the D-InSAR and SBAS-InSAR measurements had better agreement than that from the PS-InSAR measurement. The maximum deformation rate attributed to subsurface water injection for the period from 2003 to 2010 was up to approximately 33 mm/year in the line of sight (LOS) direction. The interferometric phase change from November 2007 to June 2010 showed a clear deformation pattern, and the rebound center has been expanding in scale and increasing in quantity.
      Citation: Applied Sciences
      PubDate: 2017-07-30
      DOI: 10.3390/app7080772
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 773: Thermal Energy Diffusion
           

    • Authors: Jang Jyegal
      First page: 773
      Abstract: The currently used generalized Einstein relation for degenerate semiconductors with isotropic nonparabolic energy bands produces physically improper results, as well as losing numerical accuracy for large values of nonparabolicity parameters at room temperature. Therefore, a new generalized Einstein relation (a macroscopic equation and a formula) is derived from the semiclassical momentum balance equation based on a drift-diffusion approximation, by introducing a new concept of the effective temperature of a carrier gas for generalization of the classical kinetic theory for nonideal gases of carriers in semiconductors. The proposed formula takes into account the carrier thermal energy diffusion effect completely, so that it can accurately reflect the effect of band nonparabolicity on the ratio of the diffusion coefficient to the mobility for carriers in degenerate semiconductors. From the results evaluated with the formula, new and critically important nonparabolicity effects are observed. It is shown that the new generalized Einstein relation is valid for applied electrical fields of the full linear regime. In addition, useful figures are also presented, from which the ratio of the diffusion coefficient to mobility, as well as the Fermi energy, can be easily determined from the electron concentration, or doping density, for a given semiconductor material.
      Citation: Applied Sciences
      PubDate: 2017-07-31
      DOI: 10.3390/app7080773
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 774: Electromagnetic Field Analysis of an
           Electric Dipole Antenna Based on a Surface Integral Equation in
           Multilayered Dissipative Media

    • Authors: Yidong Xu, Wei Xue, Yingsong Li, Lili Guo, Wenjing Shang
      First page: 774
      Abstract: In this paper, a novel method based on the Poggio–Miller–Chang-Harrington–Wu–Tsai (PMCHWT) integral equation is presented to study the electromagnetic fields excited by vertical or horizontal electric dipoles in the presence of a layered region which consists of K-layered dissipative media and the air above. To transform the continuous integral equation into a block tridiagonal matrix with the feature of convenient solution, the Rao–Wilton–Glisson (RWG) functions are introduced as expansion and testing functions. The electromagnetic fields excited by an electric dipole are calculated and compared with the available results, where the electric dipole antenna is buried in the non-planar air–sea–seabed, air–rock–earth–mine, and multilayered sphere structures. The analysis and computations demonstrate that the method exhibits high accuracy and solving performance in the near field propagation region.
      Citation: Applied Sciences
      PubDate: 2017-07-30
      DOI: 10.3390/app7080774
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 775: Planetary Gearbox Fault diagnosis via
           Joint Amplitude and Frequency Demodulation Analysis Based on Variational
           Mode Decomposition

    • Authors: Zhipeng Feng, Dong Zhang, Ming Zuo
      First page: 775
      Abstract: Planetary gearbox vibration signals have strong modulation features due to the amplitude modulation and frequency modulation (AM-FM) effect of gear faults, as well as the amplitude modulation (AM) effect of time-varying vibration transfer paths, on gear meshing vibrations. This results in an involute sidebands structure in Fourier spectrum, possibly misleading fault diagnosis. The modulating frequency of both amplitude modulation (AM) and frequency modulation (FM) parts is closely related to the gear fault characteristic frequency. This inspires the idea of joint amplitude and frequency demodulation analysis, thus addressing the complex sidebands issue inherent in Fourier spectrum. Demodulation analysis requires mono-component signals for accurate estimation of instantaneous frequency, and proper selection of an AM-FM component sensitive to gear fault. To this end, we firstly decompose the complex signal into intrinsic mode functions (IMFs) via variational mode decomposition (VMD), by exploiting its capability in decomposing complex modulated signal into constituent AM-FM components. For effective application of VMD in complex planetary gearbox signal analysis, we propose a method to determine a key parameter in VMD, i.e. the number of IMFs to be separated. For accurate instantaneous frequency estimation, we decompose IMFs via empirical AM-FM decomposition, to remove the influence of AM on instantaneous frequency estimation. Then, we select the sensitive IMF that contains the main gear fault information for further demodulation analysis. In order to properly select the sensitive IMF, we propose a criterion based on the gear vibration characteristics and the VMD properties. Finally, we obtain the amplitude and frequency demodulated spectra by applying Fourier transform to the amplitude envelope and instantaneous frequency of the selected sensitive IMF. According to the characteristics exhibited in the demodulated spectra, we can detect planetary gearbox fault. The proposed method is illustrated via a numerical simulated planetary gearbox vibration signal, and is further validated using lab experimental vibration signals of a planetary gearbox. Faults on all the three types of gear (sun, planet and ring) are successfully identified.
      Citation: Applied Sciences
      PubDate: 2017-07-30
      DOI: 10.3390/app7080775
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 776: Remote Servo Tuning System for
           Multi-Axis CNC Machine Tools Using a Virtual Machine Tool Approach

    • Authors: Chien-Yu Lin, Ching-Hung Lee
      First page: 776
      Abstract: Servo systems affect the performances of machining in accuracy and surface quality for high speed and precision machine tools. This study introduces an efficient servo tuning technique for Computer Numerical Control (CNC) feed drive systems using particle swarm optimization (PSO) algorithm by virtual machine tool approach. The proposed approach contained a system identification phase and a servo tuning phase based on the same bandwidth for all axes feed drive systems. The PSO algorithm was adopted to obtain the system parameters and maximize the corresponding bandwidth. An efficient two-step servo tuning method based on gain and phase margins was proposed for high speed and precision requirements. All feed drive systems controller gains were optimized simultaneously for synchronization. A remote system called Machine Dr. was established for servo tuning and monitoring. Simulation and experimental results were introduced to illustrate the effectiveness of the proposed approach.
      Citation: Applied Sciences
      PubDate: 2017-07-30
      DOI: 10.3390/app7080776
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 777: A Framework for Proactive Resource
           Provisioning in IaaS Clouds

    • Authors: Yi-Hsuan Lee, Kuo-Chan Huang, Cheng-Hsien Wu, Yen-Hsuan Kuo, Kuan-Chou Lai
      First page: 777
      Abstract: Cloud computing is an emerging technology for rapidly provisioning and releasing resources on-demand from a shared resource pool. When big data is analyzed/mined on the cloud platform, the efficiency of resource provisioning would affect the system performance. This work proposes a framework for proactive resource provisioning in IaaS (Infrastructure as a Service) clouds to improve system performance. The proposed framework consists of the virtual cluster computing system, the profiling system, the resource management system, and the monitoring system. In this framework, the over-commit mechanism is applied to improve resource utilization. Furthermore, a proactive task scheduling approach is also present to prevent the postponement of tasks in critical stages, especially when the amount of aggregated resources requested by virtual machines exceeds that of available resources on the over-committed physical machines. Experimental results show that the over-commit approach indeed improves the resource utilization. However, when the degree of applying the over-commit approach increases, the burden of this proposed approach also conceivably increases. Therefore, the proposed framework further applies the proactive task scheduling approach to execute the time-critical tasks earlier to shorten the processing time. A small-scale cloud system including 3 servers is built for experiments. Preliminary experimental results show the performance improvement of our proposed framework in IaaS clouds.
      Citation: Applied Sciences
      PubDate: 2017-07-31
      DOI: 10.3390/app7080777
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 778: Removal of Crotamiton from Reverse
           Osmosis Concentrate by a TiO2/Zeolite Composite Sheet

    • Authors: Qun Xiang, Shuji Fukahori, Naoyuki Yamashita, Hiroaki Tanaka, Taku Fujiwara
      First page: 778
      Abstract: Reverse osmosis (RO) concentrate from wastewater reuse facilities contains concentrated emerging pollutants, such as pharmaceuticals. In this research, a paper-like composite sheet consisting of titanium dioxide (TiO2) and zeolite was synthesized, and removal of the antipruritic agent crotamiton from RO concentrate was studied using the TiO2/zeolite composite sheet. The RO concentrate was obtained from a pilot-scale municipal secondary effluent reclamation plant. Effective immobilization of the two powders in the sheet made it easy to handle and to separate the photocatalyst and adsorbent from purified water. The TiO2/zeolite composite sheet showed excellent performance for crotamiton adsorption without obvious inhibition by other components in the RO concentrate. With ultraviolet irradiation, crotamiton was simultaneously removed through adsorption and photocatalysis. The photocatalytic decomposition of crotamiton in the RO concentrate was significantly inhibited by the water matrix at high initial crotamiton concentrations, whereas rapid decomposition was achieved at low initial crotamiton concentrations. The major degradation intermediates were also adsorbed by the composite sheet. This result provides a promising method of mitigating secondary pollution caused by the harmful intermediates produced during advanced oxidation processes. The cyclic use of the HSZ-385/P25 composite sheet indicated the feasibility of continuously removing crotamiton from RO concentrate.
      Citation: Applied Sciences
      PubDate: 2017-07-31
      DOI: 10.3390/app7080778
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 779: Mechanical Resilience of Modified
           Bitumen at Different Cooling Rates: A Rheological and Atomic Force
           Microscopy Investigation

    • Authors: Cesare Rossi, Saltanat Ashimova, Pietro Calandra, Maria Santo, Ruggero Angelico
      First page: 779
      Abstract: Due to the wide variation in geographic and climatic conditions, the search for high-performance bituminous materials is becoming more and more urgent to increase the useful life of pavements and reduce the enormous cost of road maintenance. Extensive research has been done by testing various bitumen modifiers, although most of them are petroleum-derived additives, such as polymers, rubbers and plastic, which in turn do not prevent oxidative aging of the binder. Thus, as an alternative to the most common polymeric rheological modifiers, selected binder additives falling in the categories of organosilane (P2KA), polyphosphoric acid (PPA) and food grade phospholipids (LCS) were homogeneously mixed to a base bitumen. The goal was to analyse the micro-morphology of the bitumens (neat and modified) subjected to different cooling rates and to find the corresponding correlations in the mechanical response domain. Therefore, microstructural investigations carried out by Atomic Force Microscopy (AFM) and fundamental rheological tests based on oscillatory dynamic rheology, were used to evaluate the effect of additives on the bitumen structure and compared with pristine binder as a reference. The tested bitumen additives have been shown to elicit different mechanical behaviours by varying the cooling rate. By comparing rheological data, analysed in the framework of the “weak gel” model, and AFM images, it was found that both P2KA and PPA altered the material structure in a different manner whereas LCS revealed superior performances, acting as “mechanical buffer” in the whole explored range of cooling rates.
      Citation: Applied Sciences
      PubDate: 2017-07-31
      DOI: 10.3390/app7080779
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 780: An Improved Dispatching Method
           (a-HPDB) for Automated Material Handling System with Active Rolling Belt
           for 450 mm Wafer Fabrication

    • Authors: Chia-Nan Wang, Hsien-Pin Hsu, Van-Vinh Tran
      First page: 780
      Abstract: The semiconductor industry is facing the transition from 300 mm to 450 mm wafer fabrication. Due to the increased size and weight, 450 mm wafers will pose unprecedented challenges on semiconductor wafer fabrication. To better handle and transport 450 mm wafers, an advanced Automated Material Handling System (AMHS) is definitely required. Though conveyor-based AMHS is expected to be suitable for 450 mm wafer fabrication, still it faces two main problems, traffic-jam problem and lot-prioritization. To address the two problems, in this research we have proposed an improved dispatching method, termed Heuristic Preemptive Dispatching Method using Activated Roller Belt (a-HPDB). We have developed some effective rules for the a-HPDB based on Activated Roller Belt (ARB). In addition, we have conducted experiments to investigate its effectiveness. Compared with the HPDB and R-HPD, two dispatching rules proposed in previous studies, our experimental results showed the a-HPDB had a better performance in terms of average lot delivery time (ALDT). For hot lots and normal lots, the a-HPDB had advantages of 4.14% and 8.92% over the HPDB and advantages of 4.89% and 8.52% over R-HPD, respectively.
      Citation: Applied Sciences
      PubDate: 2017-07-31
      DOI: 10.3390/app7080780
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 781: A New Damage Assessment Method by
           Means of Neural Network and Multi-Sensor Satellite Data

    • Authors: Alessandro Piscini, Vito Romaniello, Christian Bignami, Salvatore Stramondo
      First page: 781
      Abstract: Artificial Neural Network (ANN) is a valuable and well-established inversion technique for the estimation of geophysical parameters from satellite images. After training, ANNs are able to generate very fast products for several types of applications. Satellite remote sensing is an efficient way to detect and map strong earthquake damage for contributing to post-disaster activities during emergency phases. This work aims at presenting an application of the ANN inversion technique addressed to the evaluation of building collapse ratio (CR), defined as the number of collapsed buildings with respect to the total number of buildings in a city block, by employing optical and SAR satellite data. This is done in order to directly relate changes in images with damage that has occurred during strong earthquakes. Furthermore, once they have been trained, neural networks can be used rapidly at application stage. The goal was to obtain a general tool suitable for re-use in different scenarios. An ANN has been implemented in order to emulate a regression model and to estimate the CR as a continuous function. The adopted ANN has been trained using some features obtained from optical and Synthetic Aperture Radar (SAR) images, as inputs, and the corresponding values of collapse ratio obtained from the survey of the 2010 M7 Haiti Earthquake, i.e., as target output. As regards the optical data, we selected three change parameters: the Normalized Difference Index (NDI), the Kullback–Leibler divergence (KLD), and Mutual Information (MI). Concerning the SAR images, the Intensity Correlation Difference (ICD) and the KLD parameters have been considered. Exploiting an object-oriented approach, a segmentation of the study area into several regions has been performed. In particular, damage maps have been generated by considering a set of polygons (in which satellite parameters have been calculated) extracted from the open source Open Street Map (OSM) geo-database. The trained ANN has been proposed for the M6.0 Amatrice earthquake that occurred on 24 August 2016, in central Italy, by using the features extracted from Sentinel-2 and COSMO-SkyMed images as input. The results show that the ANN is able to retrieve a building collapse ratio with good accuracy. In particular, the fusion approach modelled the collapse ratio characterized by high values of CR (more than 0.5) over the historical center that agrees with observed damages. Since the technique is independent from different typologies of input data (i.e., for radiometric or spatial resolution characteristics), the study demonstrated the strength of the proposed approach for estimating damaged areas and its importance in near real time monitoring activities, owing to its fast application.
      Citation: Applied Sciences
      PubDate: 2017-08-01
      DOI: 10.3390/app7080781
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 782: Enhancement of Sea Wave Potential
           Energy with Under-Sea Periodic Structures: A Simulation and Laboratory
           Study

    • Authors: Shuo-Feng Chiu, Jyun-Jie Wang, Ssu-Che Wang, Sheng Chao
      First page: 782
      Abstract: This paper is devoted to a theoretical investigation on the wave amplitude enhancement of surface sea water waves with under-sea periodic arrays of cylinders. A two-dimensional shallow water wave equation is derived and solved by using the plane-wave expansion method. The lattice types studied here include triangular, square and hexagonal lattices. These under-sea structures alter the sea bottom topography and induce constructive interference on the surface water waves. Given that the wave potential energy is dependent on the square of the wave amplitude, this mechanism can thus be used to increase the potential energy. It is shown that the enhancement factor depends on two geometric parameters and the maximum wave amplitude can be found by adjusting the two geometric parameters. Among the lattice types, the triangular and square lattice structures can induce more wave amplitude enhancement (and thus potential energy) than the hexagonal structures. Guided by numerical simulations, we have performed a reduced-scale water tank experiment to demonstrate the feasibility of the proposed idea. Preliminary experimental results show promising evidence of the predicted wave amplitude enhancement, suggesting perspective real-scale nearshore deployment and test.
      Citation: Applied Sciences
      PubDate: 2017-08-02
      DOI: 10.3390/app7080782
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 783: Comparison of Basic Notch Filters for
           Semiconductor Optical Amplifier Pattern Effect Mitigation

    • Authors: Zoe Rizou, Kyriakos Zoiros, Antonios Hatziefremidis
      First page: 783
      Abstract: We conduct a thorough comparison of two basic notch filters employed to mitigate the pattern effect that manifests when semiconductor optical amplifiers (SOAs) serve linear amplification purposes. The filters are implemented using as the building architecture the optical delay interferometer (ODI) and the microring resonator (MRR). We formulate and follow a rational procedure, which involves identifying and applying the appropriate conditions for the filters’ spectral response slope related to the SOA pattern effect suppression mechanism. We thus extract the values of the free spectral range and detuning of each filter, which allow one to equivocally realize the pursued comparison. We define suitable performance metrics and obtain simulation results for each filter. The quantitative comparison reveals that most employed metrics are better with the MRR than with the ODI. Although the difference in performance is small, it is sufficient to justify considering also using the MRR for the intended purpose. Finally, we concisely discuss practical implementation issues of these notch filters and further make a qualitative comparison between them in terms of their inherent advantages and disadvantages. This discussion reveals that each scheme has distinct features that render it appropriate for supporting SOA direct signal amplification applications with a suppressed pattern effect.
      Citation: Applied Sciences
      PubDate: 2017-08-02
      DOI: 10.3390/app7080783
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 784: Comparative Performance of
           Thermoacoustic Heat Exchangers with Different Pore Geometries in
           Oscillatory Flow. Implementation of Experimental Techniques

    • Authors: Antonio Piccolo, Roberto Siclari, Fabrizio Rando, Mauro Cannistraro
      First page: 784
      Abstract: Heat exchangers (HXs) constitute key components of thermoacoustic devices and play an important role in determining the overall engine performance. In oscillatory flow conditions, however, standard heat transfer correlations for steady flows cannot be directly applied to thermoacoustic HXs, for which reliable and univocal design criteria are still lacking. This work is concerned with the initial stage of a research aimed at studying the thermal performance of thermoacoustic HXs. The paper reports a detailed discussion of the design and fabrication of the experimental set-up, measurement methodology and test-HXs characterized by two different pore geometries, namely a circular pore geometry and a rectangular (i.e., straight fins) pore geometry. The test rig is constituted by a standing wave engine where the test HXs play the role of ambient HXs. The experiment is conceived to allow the variation of a range of testing conditions such as drive ratio, operation frequency, acoustic particle velocity, etc. The procedure for estimating the gas side heat transfer coefficient for the two involved geometries is described. Some preliminary experimental results concerning the HX with straight fins are also shown. The present research could help in achieving a deeper understanding of the heat transfer processes affecting HXs under oscillating flow regime and in developing design optimization procedures.
      Citation: Applied Sciences
      PubDate: 2017-08-02
      DOI: 10.3390/app7080784
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 785: An Efficient Synthesis of Novel
           Pyrazole-Based Heterocycles as Potential Antitumor Agents

    • Authors: Magda Abdallah, Sobhi Gomha, Ikhlass Abbas, Mariam Kazem, Seham Alterary, Yahia Mabkhot
      First page: 785
      Abstract: A new series of pyrazolylpyridines was prepared by reaction of ethyl-3-acetyl-1,5-diphenyl-1H-pyrazole-4-carboxylate with the appropriate aldehyde, malononitrile, or ethyl acetoacetate and an excess of ammonium acetate under reflux in acetic acid. Similarly, two novel bipyridine derivatives were prepared by the above reaction using terephthaldehyde in lieu of benzaldehyde derivatives. In addition, a series of 1,2,4-triazolo[4,3-a]pyrimidines was synthesized by a reaction of 6-(pyrazol-3-yl)pyrimidine-2-thione with a number of hydrazonoyl chlorides in dioxane and in the presence of triethylamine. The structure of the produced compounds was established by elemental analyses and spectral methods, and the mechanisms of their formation was discussed. Furthermore, the pyrazolyl-pyridine derivatives were tested as anticancer agents and the results obtained showed that some of them revealed high activity against human hepatocellular carcinoma (HEPG2) cell lines.
      Citation: Applied Sciences
      PubDate: 2017-08-03
      DOI: 10.3390/app7080785
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 786: A Feature-Based Structural Measure:
           An Image Similarity Measure for Face Recognition

    • Authors: Noor Shnain, Zahir Hussain, Song Lu
      First page: 786
      Abstract: Facial recognition is one of the most challenging and interesting problems within the field of computer vision and pattern recognition. During the last few years, it has gained special attention due to its importance in relation to current issues such as security, surveillance systems and forensics analysis. Despite this high level of attention to facial recognition, the success is still limited by certain conditions; there is no method which gives reliable results in all situations. In this paper, we propose an efficient similarity index that resolves the shortcomings of the existing measures of feature and structural similarity. This measure, called the Feature-Based Structural Measure (FSM), combines the best features of the well-known SSIM (structural similarity index measure) and FSIM (feature similarity index measure) approaches, striking a balance between performance for similar and dissimilar images of human faces. In addition to the statistical structural properties provided by SSIM, edge detection is incorporated in FSM as a distinctive structural feature. Its performance is tested for a wide range of PSNR (peak signal-to-noise ratio), using ORL (Olivetti Research Laboratory, now AT&T Laboratory Cambridge) and FEI (Faculty of Industrial Engineering, São Bernardo do Campo, São Paulo, Brazil) databases. The proposed measure is tested under conditions of Gaussian noise; simulation results show that the proposed FSM outperforms the well-known SSIM and FSIM approaches in its efficiency of similarity detection and recognition of human faces.
      Citation: Applied Sciences
      PubDate: 2017-08-03
      DOI: 10.3390/app7080786
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 787: A Novel Reactive Power Optimization
           in Distribution Network Based on Typical Scenarios Partitioning and Load
           Distribution Matching Method

    • Authors: Yuqi Ji, Keyan Liu, Guangfei Geng, Wanxing Sheng, Xiaoli Meng, Dongli Jia, Kaiyuan He
      First page: 787
      Abstract: This paper proposed an entropy weight optimum seeking method (EWOSM) based on the typical scenarios partitioning and load distribution matching, to solve the reactive power optimization problem in distribution network under the background of big data. Firstly, the mathematic model of reactive power optimization is provided to analyze the relationship between the data source and the optimization schemes in distribution network, which illustrate the feasibility of using large amount of historical data to solve reactive power optimization. Then, the typical scenarios partitioning method and load distribution matching method are presented, which can select out some loads that have the same or similar distributions with the load to be optimized from historical database rapidly, and the corresponding historical optimization schemes are used as the alternatives. As the reactive power optimization is a multi-objective problem, the multi-attribute decision making method based on entropy weight method is used to select out the optimal scheme from the alternatives. The objective weights of evaluation indexes are determined by entropy weight method, and then the multi-attribute decision making problem is transformed to a single attribute decision making problem. Finally, the proposed method is tested on several systems with different scales and compared with existing methods to prove the validity and superiority.
      Citation: Applied Sciences
      PubDate: 2017-08-03
      DOI: 10.3390/app7080787
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 788: Guest Editors’
           Note—Special Issue on Spatial Audio

    • Authors: Woon-Seng Gan, Jung-Woo Choi
      First page: 788
      Abstract: n/a
      Citation: Applied Sciences
      PubDate: 2017-08-03
      DOI: 10.3390/app7080788
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 789: Structural Health Monitoring (SHM) of
           Civil Structures

    • Authors: Gangbing Song, Chuji Wang, Bo Wang
      First page: 789
      Abstract: As newer and more reliable ways of construction were developed, civilization began to spread out further and retain functional infrastructure for longer periods of time.[...]
      Citation: Applied Sciences
      PubDate: 2017-08-04
      DOI: 10.3390/app7080789
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 790: Experimental Tests and Aeroacoustic
           Simulations of the Control of Cavity Tone by Plasma Actuators

    • Authors: Hiroshi Yokoyama, Isamu Tanimoto, Akiyoshi Iida
      First page: 790
      Abstract: A plasma actuator comprising a dielectric layer sandwiched between upper and lower electrodes can induce a flow from the upper to lower electrode by means of an externally-applied electric field. Our objective is to clarify the mechanism by which such actuators can control the cavity tone. Plasma actuators, with the electrodes elongated in the streamwise direction and aligned in the spanwise direction, were placed in the incoming boundary of a deep cavity with a depth-to-length ratio of 2.5. By using this experimental arrangement, the amount of sound reduction (“control effect”) produced by actuators of differing dimensions was measured. Direct aeroacoustic simulations were performed for controlling the cavity tone by using these actuators, where the distributions of the body forces applied by the actuators were determined from measurements of the plasma luminescence. The predicted control effects on the flow and sound fields were found to agree well with the experimental results. The simulations show that longitudinal streamwise vortices are introduced in the incoming boundary by the actuators, and the vortices form rib structures in the cavity flow. These vortices distort and weaken the two-dimensional vortices responsible for producing the cavity tone, causing the tonal sound to be reduced.
      Citation: Applied Sciences
      PubDate: 2017-08-04
      DOI: 10.3390/app7080790
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 791: Reliability-Based and Cost-Oriented
           Product Optimization Integrating Fuzzy Reasoning Petri Nets, Interval
           Expert Evaluation and Cultural-Based DMOPSO Using Crowding Distance
           Sorting

    • Authors: Zhaoxi Hong, Yixiong Feng, Zhongkai Li, Guangdong Tian, Jianrong Tan
      First page: 791
      Abstract: In reliability-based and cost-oriented product optimization, the target product reliability is apportioned to subsystems or components to achieve the maximum reliability and minimum cost. Main challenges to conducting such optimization design lie in how to simultaneously consider subsystem division, uncertain evaluation provided by experts for essential factors, and dynamic propagation of product failure. To overcome these problems, a reliability-based and cost-oriented product optimization method integrating fuzzy reasoning Petri net (FRPN), interval expert evaluation and cultural-based dynamic multi-objective particle swarm optimization (DMOPSO) using crowding distance sorting is proposed in this paper. Subsystem division is performed based on failure decoupling, and then subsystem weights are calculated with FRPN reflecting dynamic and uncertain failure propagation, as well as interval expert evaluation considering six essential factors. A mathematical model of reliability-based and cost-oriented product optimization is established, and the cultural-based DMOPSO with crowding distance sorting is utilized to obtain the optimized design scheme. The efficiency and effectiveness of the proposed method are demonstrated by the numerical example of the optimization design for a computer numerically controlled (CNC) machine tool.
      Citation: Applied Sciences
      PubDate: 2017-08-04
      DOI: 10.3390/app7080791
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 792: Contact Pressure and Strain Energy
           Density of Hyperelastic U-shaped Monolithic Seals under Axial and Radial
           Compressions in an Insulating Joint: A Numerical Study

    • Authors: Jinmu Jung, Inhwan Hwang, Donghwan Lee
      First page: 792
      Abstract: In insulation joints, elastomeric U-shaped monolithic seals (UMSs) are replacing O-ring systems because of their enhanced sealing capabilities for the oil and gas industries. UMSs are compressed axially during assembly and radially when pressurized in operation. The reliability of UMSs due to the displacement imposed during assembly and the internal pressure in operation is influenced by the axial compression ratio, thickness ratio (TR), and geometric complexity. In this study, the hyperelastic behavior of elastomeric UMSs under axial and radial compressions is investigated using axisymmetric finite-element analysis. Twelve examples of UMSs with three geometric restraints (open grooves on both sides (type 1), an open groove on one side only (type 2), and no groove (type 3)) and four thickness ratios (TR = 0.25, 0.50, 1.00, and 1.50) are evaluated. To analyze nonlinear elastomeric materials, neo-Hookean constitutive equations are applied and the UMSs are considered as being a nearly incompressible hyperelastic material with a Poisson’s ratio of 0.499. The failure and detachment risks of UMSs are analyzed in terms of the equivalent stress, gap distance, contact pressure, and strain energy density. It is advantageous that the smaller the TR, the smaller the stress distribution. However, the generation of broader detachment regions is observed. Type 1 symmetrically shows the lowest stress distribution and the smallest detachment region, whereas type 3 symmetrically shows the highest values. Type 3 (TR = 0.25) shows the broadest detachment region in the arc-length range from −15.7 to 15.7 mm, whereas the largest gap of 0.7 mm is observed in type 2 (TR = 0.5). For all types, the detachment region disappears completely at TR = 1.0 or higher, which implies that full sealing is occurring. The average contact pressure increases exponentially during axial compression (in assembly) and linearly during radial compression (in operation). The largest contact pressure of 31.5 MPa is observed in type 3 (TR = 1.5), while the lowest is observed in type 1 (TR = 0.25). As for the strain energy density, type 3 at TR = 0.25 shows the largest increase in the strain energy density with 1.75 MJ/m3, while type 1 shows the most stable values of all cases. In conclusion, the lowest risk of failure of a nonlinear hyperelastic UMS was investigated numerically with minor equivalent stress and detachment region with higher contact pressure, which can be taken into account to ensure the reliability of the UMS.
      Citation: Applied Sciences
      PubDate: 2017-08-04
      DOI: 10.3390/app7080792
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 793: Effect of Organic Stabilizers on
           Silver Nanoparticles Fabricated by Femtosecond Pulsed Laser Ablation

    • Authors: Pablo Díaz-Núñez, Jesús González-Izquierdo, Guillermo González-Rubio, Andrés Guerrero-Martínez, Antonio Rivera, José Perlado, Luis Bañares, Ovidio Peña-Rodríguez
      First page: 793
      Abstract: Laser ablation has several advantages over the chemical synthesis of nanoparticles due to its simplicity and because it is a faster and cleaner process. In this paper, we use femtosecond laser ablation to generate highly concentrated silver colloidal nanoparticle solutions. Those high concentrations usually lead to agglomeration of the nanoparticles, rendering the solution nearly useless. We employ two different organic stabilizers (hexadecyltrimethylammonium bromide, CTAB, and polyvinylpyrrolidone, PVP) to avoid this problem and study their effect on the nanoparticle size distribution, structural characteristics, and the solution concentration.
      Citation: Applied Sciences
      PubDate: 2017-08-04
      DOI: 10.3390/app7080793
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 794: Improving Asphalt Mixture Performance
           by Partially Replacing Bitumen with Waste Motor Oil and Elastomer
           Modifiers

    • Authors: Sara Fernandes, Joana Peralta, Joel Oliveira, R. Williams, Hugo Silva
      First page: 794
      Abstract: The environmental concern about waste generation and the gradual decrease of oil reserves has led the way to finding new waste materials that may partially replace the bitumens used in the road paving industry. Used motor oil from vehicles is a waste product that could answer that demand, but it can also drastically reduce the viscosity, increasing the asphalt mixture’s rutting potential. Therefore, polymer modification should be used in order to avoid compromising the required performance of asphalt mixtures when higher amounts of waste motor oil are used. Thus, this study was aimed at assessing the performance of an asphalt binder/mixture obtained by replacing part of a paving grade bitumen (35/50) with 10% waste motor oil and 5% styrene-butadiene-styrene (SBS) as an elastomer modifier. A comparison was also made with the results of a previous study using a blend of bio-oil from fast pyrolysis and ground tire rubber modifier as a partial substitute for usual PG64-22 bitumen. The asphalt binders were tested by means of Fourier infrared spectra and dynamic shear rheology, namely by assessing their continuous high-performance grade. Later, the water sensitivity, fatigue cracking resistance, dynamic modulus and rut resistance performance of the resulting asphalt mixtures was evaluated. It was concluded that the new binder studied in this work improves the asphalt mixture’s performance, making it an excellent solution for paving works.
      Citation: Applied Sciences
      PubDate: 2017-08-05
      DOI: 10.3390/app7080794
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 795: An Innovative Dual-Column System for
           Heavy Metallic Ion Sorption by Natural Zeolite

    • Authors: Amanda Ciosek, Grace Luk
      First page: 795
      Abstract: This study investigates the design and performance of a novel sorption system containing natural zeolite. The apparatus consists of packed, fixed-bed, dual-columns with custom automated controls and sampling chambers, connected in series and stock fed by a metering pump at a controlled adjustable distribution. The purpose of the system is to remove heavy metallic ions predominately found in acid mine drainage, including lead (Pb2+), copper (Cu2+), iron (Fe3+), nickel (Ni2+) and zinc (Zn2+), combined in equal equivalence to form an acidified total 10 meq/L aqueous solution. Reported trends on the zeolite’s preference to these heavy metallic ions is established in the system breakthrough curve, as Pb2+ >> Fe3+ > Cu2+ > Zn2+ >> Ni2+. Within a 3-h contact period, Pb2+ is completely removed from both columns. Insufficient Ni2+ removal is achieved by either column with the promptest breakthrough attained, as zeolite demonstrates the least affinity towards it; however, a 48.97% removal is observed in the cumulative collection at the completion of the analysis period. The empty bed contact times for the first and second columns are 20 and 30 min, respectively; indicating a higher bed capacity at breakthrough and a lower usage rate of the zeolite mineral in the second column. This sorption system experimentally demonstrates the potential for industrial wastewater treatment technology development.
      Citation: Applied Sciences
      PubDate: 2017-08-05
      DOI: 10.3390/app7080795
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 796: A Method for Ferulic Acid Production
           from Rice Bran Oil Soapstock Using a Homogenous System

    • Authors: Hoa Truong, Manh Do Van, Long Duc Huynh, Linh Thi Nguyen, Anh Do Tuan, Thao Le Xuan Thanh, Hung Duong Phuoc, Norimichi Takenaka, Kiyoshi Imamura, Yasuaki Maeda
      First page: 796
      Abstract: Ferulic acid (FA) is widely used as an antioxidant, e.g., as a Ultraviolet (UV) protectant in cosmetics and in various medical applications. It has been produced by the hydrolysis of γ-oryzanol found in rice bran oil soapstock. In this study, the base-catalyzed, homogenous hydrolysis of γ-oryzanol was conducted using various ratios of potassium hydroxide (KOH) to γ-oryzanol, initial concentrations of γ-oryzanol in the reaction mixture, and ratios of ethanol (EtOH) (as cosolvent)/ethyl acetate (EtOAc) (γ-oryzanol solution). Acceleration of the reaction using a planar type of ultrasound sonicator (78 and 130 kHz) at different reaction temperatures was explored. By using a heating method, the 80% yield of FA was attained at 75 °C in 4 h under homogeneous conditions (initial concentration of γ-oryzanol 12 mg/mL, the KOH/γ-oryzanol ratio (wt/wt) 10/1, and EtOH/EtOAc ratio (v/v) 5/1). With the assistance of 78 and 130 kHz irradiation, the yields reached 90%. The heating method was applied for the γ-oryzanol-containing extract prepared from rice bran oil soapstock. From soapstock, the 74.3% yield of FA was obtained, but 20% of the trans-FA in the reaction mixture was transformed into cis-form within one month.
      Citation: Applied Sciences
      PubDate: 2017-08-05
      DOI: 10.3390/app7080796
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 797: Dynamic Performance Analysis for an
           Absorption Chiller under Different Working Conditions

    • Authors: Jian Wang, Sheng Shang, Xianting Li, Baolong Wang, Wei Wu, Wenxing Shi
      First page: 797
      Abstract: Due to the merits of energy saving and environmental protection, the absorption chiller (AC) has attracted a lot of attention, and previous studies only concentrated on the dynamic response of the AC under a single working condition. However, the working conditions are usually variable, and the dynamic performance under different working conditions is beneficial for the adjustment of AC and the control of the whole system, of which the stabilization can be affected by the AC transient process. Therefore, the steady and dynamic models of a single-effect H2O-LiBr absorption chiller are built up, the thermal inertia and fluid storage are also taken into consideration. And the dynamic performance analyses of the AC are completed under different external parameters. Furthermore, a whole system using AC in a process plant is analyzed. As a conclusion, the time required to reach a new steady-state (relaxation time) increases when the step change of the generator inlet temperature becomes large, the cooling water inlet temperature rises, or the evaporator inlet temperature decreases. In addition, the control strategy considering the AC dynamic performance is favorable to the operation of the whole system.
      Citation: Applied Sciences
      PubDate: 2017-08-05
      DOI: 10.3390/app7080797
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 798: Real-Time Recognition of Calling
           Pattern and Behaviour of Mobile Phone Users through Anomaly Detection and
           Dynamically-Evolving Clustering

    • Authors: José Iglesias, Agapito Ledezma, Araceli Sanchis, Plamen Angelov
      First page: 798
      Abstract: In the competitive telecommunications market, the information that the mobile telecom operators can obtain by regularly analysing their massive stored call logs, is of great interest. Although the data that can be extracted nowadays from mobile phones have been enriched with much information, the data solely from the call logs can give us vital information about the customers. This information is usually related with the calling behaviour of their customers and it can be used to manage them. However, the analysis of these data is normally very complex because of the vast data stream to analyse. Thus, efficient data mining techniques need to be used for this purpose. In this paper, a novel approach to analyse call detail records (CDR) is proposed, with the main goal to extract and cluster different calling patterns or behaviours, and to detect outliers. The main novelty of this approach is that it works in real-time using an evolving and recursive framework.
      Citation: Applied Sciences
      PubDate: 2017-08-05
      DOI: 10.3390/app7080798
      Issue No: Vol. 7, No. 8 (2017)
       
  • Applied Sciences, Vol. 7, Pages 699: An Energy Demodulation Based Fiber
           Optic Sensing System for Landslide Early-Warning

    • Authors: Xing Wang, Bin Shi, Guangqing Wei, Shenen Chen
      First page: 699
      Abstract: To help reduce the impact of geo-hazards, an innovative landslide early-warning technology based on an energy demodulation-based fiber optic sensing (FOS-LW for short) technology, is introduced in this paper. FOS-LW measures the energy change in a sensing fiber at the segment of micro-bending, which can be caused by landslide movements, and automatically raises an alarm as soon as the measured signal intensity in the fiber reaches a pre-set threshold. Based on the sensing of micro-bending losses in the fiber optics, a two-event sensing algorithm has been developed for the landslide early-warning. The feasibility of the FOS-LW technology is verified through laboratory simulation and field tests. The result shows that FOS-LW has some unique features—such as the graded alarm, real-time responses, remote monitoring, low cost and passive optical network—and can be applied in the early-warning of landslides.
      PubDate: 2017-07-07
      DOI: 10.3390/app7070699
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 700: Integrated Optical Content
           Addressable Memories (CAM) and Optical Random Access Memories (RAM) for
           Ultra-Fast Address Look-Up Operations

    • Authors: Christos Vagionas, Pavlos Maniotis, Stelios Pitris, Amalia Miliou, Nikos Pleros
      First page: 700
      Abstract: Electronic Content Addressable Memories (CAM) implement Address Look-Up (AL) table functionalities of network routers; however, they typically operate in the MHz regime, turning AL into a critical network bottleneck. In this communication, we demonstrate the first steps towards developing optical CAM alternatives to enable a re-engineering of AL memories. Firstly, we report on the photonic integration of Semiconductor Optical Amplifier-Mach Zehnder Interferometer (SOA-MZI)-based optical Flip-Flop and Random Access Memories on a monolithic InP platform, capable of storing the binary prefix-address data-bits and the outgoing port information for next hop routing, respectively. Subsequently the first optical Binary CAM cell (B-CAM) is experimentally demonstrated, comprising an InP Flip-Flop and a SOA-MZI Exclusive OR (XOR) gate for fast search operations through an XOR-based bit comparison, yielding an error-free 10 Gb/s operation. This is later extended via physical layer simulations in an optical Ternary-CAM (T-CAM) cell and a 4-bit Matchline (ML) configuration, supporting a third state of the “logical X” value towards wildcard bits of network subnet masks. The proposed functional CAM and Random Access Memories (RAM) sub-circuits may facilitate light-based Address Look-Up tables supporting search operations at 10 Gb/s and beyond, paving the way towards minimizing the disparity with the frantic optical transmission linerates, and fast re-configurability through multiple simultaneous Wavelength Division Multiplexed (WDM) memory access requests.
      PubDate: 2017-07-07
      DOI: 10.3390/app7070700
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 701: Investigation of Catalytic Effects
           and Compositional Variations in Desorption Characteristics of
           LiNH2-nanoMgH2

    • Authors: Sesha Srinivasan, Dervis Demirocak, Yogi Goswami, Elias Stefanakos
      First page: 701
      Abstract: LiNH2 and a pre-processed nanoMgH2 with 1:1 and 2:1 molar ratios were mechano-chemically milled in a high-energy planetary ball mill under inert atmosphere, and at room temperature and atmospheric pressure. Based on the thermogravimetric analysis (TGA) experiments, 2LiNH2-nanoMgH2 demonstrated superior desorption characteristics when compared to the LiNH2-nanoMgH2. The TGA studies also revealed that doping 2LiNH2-nanoMgH2 base material with 2 wt. % nanoNi catalyst enhances the sorption kinetics at lower temperatures. Additional investigation of different catalysts showed improved reaction kinetics (weight percentage of H2 released per minute) of the order TiF3 > nanoNi > nanoTi > nanoCo > nanoFe > multiwall carbon nanotube (MWCNT), and reduction in the on-set decomposition temperatures of the order nanoCo > TiF3 > nanoTi > nanoFe > nanoNi > MWCNT for the base material 2LiNH2-nanoMgH2. Pristine and catalyst-doped 2LiNH2-nanoMgH2 samples were further probed by X-ray diffraction, Fourier transform infrared spectroscopy, transmission and scanning electron microscopies, thermal programmed desorption and pressure-composition-temperature measurements to better understand the improved performance of the catalyst-doped samples, and the results are discussed.
      PubDate: 2017-07-07
      DOI: 10.3390/app7070701
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 702: Evaluation of Aging Resistance of
           Graphene Oxide Modified Asphalt

    • Authors: Shaopeng Wu, Zhijie Zhao, Yuanyuan Li, Ling Pang, Serji Amirkhanian, Martin Riara
      First page: 702
      Abstract: Graphene oxide (GO) has a unique layered structure with excellent gas and liquid blocking properties. It is widely used in many areas, such as gas sensors, carbon-based electronics, impermeable membranes, and polymeric composite materials. In order to evaluate whether GO (1% and 3% by weight of asphalt) can improve the aging resistance performance of the asphalt, 80/100 penetration grade asphalt (90 A) and styrene–butadiene–styrene modified asphalt (SBS MA) were used to prepare the GO modified asphalt by the melt blending method. The surface morphology of the GO was analyzed by scanning electron microscope (SEM). The UV aging test was conducted to simulate the aging during the service period. After UV aging test, the physical performances of GO-modified asphalts were tested, and the IC=O and IS=O increments were tested by Fourier transform infrared spectroscopy (FTIR) to evaluate the aging resistance performance of the GO modified asphalt. In addition, the rheological properties of GO modified asphalts were studied using a dynamic shear rheometer (DSR). The SEM analysis indicated that the GO exhibits many shared edges, and no agglomeration phenomenon was found. With respect to the physical performance test, the FTIR and the DSR results show that GO can improve the UV aging resistance performance of 90 A and SBS MA. In addition, the analysis indicated that the improvement effect of 3% GO is better than the 1% GO. The testing on the rheological properties of the modified asphalt indicated that the GO can also improve the thermo-oxidative aging resistance performance of asphalt.
      PubDate: 2017-07-07
      DOI: 10.3390/app7070702
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 703: An Improved Distribution Policy with
           a Maintenance Aspect for an Urban Logistic Problem

    • Authors: Nadia Ndhaief, Olivier Bistorin, Nidhal Rezg
      First page: 703
      Abstract: In this paper, we present an improved distribution plan supporting an urban distribution center (UDC) to solve the last mile problem of urban freight. This is motivated by the need of UDCs to satisfy daily demand in time under a high service level in allocated urban areas. Moreover, these demands could not be satisfied in individual cases because the delivery rate can be less than daily demand and/or affected by random failure or maintenance actions of vehicles. The scope of our work is to focus on a UDC, which needs to satisfy demands in a finite horizon. To that end, we consider a distribution policy on two sequential plans, a distribution plan correlated to a maintenance plan using a subcontracting strategy with several potential urban distribution centers (UDCs) and performing preventive maintenance to ensure deliveries for their allocated urban area. The choice of subcontractor will depend on distance, environmental and availability criteria. In doing so, we define a mathematical model for searching the best distribution and maintenance plans using a subcontracting strategy. Moreover, we consider delay for the next periods with an expensive penalty. Finally, we present a numerical example illustrating the benefits of our approach.
      PubDate: 2017-07-07
      DOI: 10.3390/app7070703
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 704: Creation of Optimal Frequency for
           Electrostatic Force Microscopy Using Direct Digital Synthesizer

    • Authors: Seunghyun Moon, Mingyu Kang, Jung-Hwan Kim, Kyeo-Reh Park, ChaeHo Shin
      First page: 704
      Abstract: Electrostatic force microscopy (EFM) is a useful technique when measuring the surface electric potential of a substrate regardless of its topography. Here, we have developed a frequency detection method for alternating current (AC) bias in EFM. Instead of an internal lock-in amplifier (LIA) for EFM that only detects ωe and 2ωe, we have used other LIAs that can amplify the amplitude of specific frequency by direct digital synthesizer (DDS), that finds the optimal frequency of surface charge images. In order to confirm the performance of the proposed methods, the electrical properties of lead zirconate titanate (PZT) and triglycine sulfate (TGS) samples were measured. In addition, we compared the performances of the frequency-detection method and the conventional EFM method. Ultimately, enhanced images could be achieved using the frequency-detection method. The optimal modulated frequency-shift for force–gradient measurements was found to be 2 kHz. Additionally, we have shown that it is possible to use a hard cantilever (K = 42 N/m, 330 kHz). Therefore, we expect that this technique can be applied to measure the electrical properties of bio-molecular films.
      PubDate: 2017-07-08
      DOI: 10.3390/app7070704
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 705: Collinear FAST CARS for Chemical
           Mapping of Gases

    • Authors: Anton Shutov, Dmitry Pestov, Narangerel Altangerel, Zhenhuan Yi, Xi Wang, Alexei Sokolov, Marlan Scully
      First page: 705
      Abstract: We examine the concentration dependence of the Coherent Anti-Stokes Raman Scattering (CARS) signal obtained for gas mixtures at various conditions using the Femtosecond Adaptive Spectroscopic Technique (FAST). We use the CARS signal of the Q-branch vibrational oscillation of molecular oxygen (1556 cm−1) to confirm the quadratic dependence of the coherent signal on the number of molecules in a test volume. In addition, we demonstrate multi-shot FAST CARS imaging of a gas flow in free space by raster-scanning the area of interest.
      PubDate: 2017-07-08
      DOI: 10.3390/app7070705
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 706: A Si-αTCP Scaffold for Biomedical
           Applications: An Experimental Study Using the Rabbit Tibia Model

    • Authors: Piedad De Aza, Miguel Rodríguez, Sergio Gehrke, José Maté-Sánchez de Val, Jose Calvo-Guirado
      First page: 706
      Abstract: We herein hypothesize that bioceramics with an appropriate architecture made of Si-αtricalcium phosphate (Si-αTCP) meet the biocompatibility and biological safety requirements for bone grafting applications. Polyurethane sponges were used as templates, soaked with ceramic slurry at different ratios and sintered at 1400 °C for 3 h at heating and cooling rates of 5 °C/min. Four critical size defects of 6 mm Ø were created in 15 NZ tibias. Three working times were established as 15, 30 and 60 days. A highly porous Si-αTCP scaffold with micro and macropores and pore interconnectivity was produced by the polymer replication method. Considerably more bone formation took place in the pores and the periphery of the implant for the Si-αTCP scaffolds than for the control group. The ceramic scaffold (68.32% ± 1.21) generated higher bone-to-implant contact (BIC) percentage values (higher quality, closer contact) than the control group, according to the histomorphometric analysis, and defect closure was significant compared with the control group. The highest percentages of BIC and bone formation were found after 60 days of implantation. These results suggest that the Si-αTCP scaffold is advantageous for initial bone regeneration.
      PubDate: 2017-07-08
      DOI: 10.3390/app7070706
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 707: Vibration Control Design for a Plate
           

    • Authors: Chih-Jer Lin, Chun-Ying Lee, Ying Liu
      First page: 707
      Abstract: This study presents vibration control using actively tunable vibration absorbers (ATVA) to suppress vibration of a thin plate. The ATVA is made of a sandwich hollow structure embedded with electrorheological fluid (ERF). ERF is considered to be one of the most important smart fluids and it is suitable to be embedded in a smart structure due to its controllable rheological property. ERF’s apparent viscosity can be controlled in response to the electric field and the change is reversible in 10 microseconds. Therefore, the physical properties of the ERF-embedded smart structure, such as the stiffness and damping coefficient, can be changed in response to the applied electric field. A mathematical model is difficult to be obtained to describe the exact characteristics of the ERF embedded ATVA because of the nonlinearity of ERF’s viscosity. Therefore, a fuzzy modeling and experimental validations of ERF-based ATVA from stationary random vibrations of thin plates are presented in this study. Because Type-2 fuzzy sets generalize Type-1 fuzzy sets so that more modeling uncertainties can be handled, a semi-active vibration controller is proposed based on Type-2 fuzzy sets. To investigate the different performances by using different types of fuzzy controllers, the experimental measurements employing both type-1 fuzzy and interval type-2 fuzzy controllers are implemented by the Compact RIO embedded system. The fuzzy modeling framework and solution methods presented in this work can be used for design, performance analysis, and optimization of ATVA from varying harmonic vibration of thin plates.
      PubDate: 2017-07-08
      DOI: 10.3390/app7070707
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 708: Potential Model Overfitting in
           Predicting Soil Carbon Content by Visible and Near-Infrared Spectroscopy

    • Authors: Lizardo Reyna, Francis Dube, Juan A. Barrera, Erick Zagal
      First page: 708
      Abstract: Soil spectroscopy is known as a rapid and cost-effective method for predicting soil properties from spectral data. The objective of this work was to build a statistical model to predict soil carbon content from spectral data by partial least squares regression using a limited number of soil samples. Soil samples were collected from two soil orders (Andisol and Ultisol), where the dominant land cover is native Nothofagus forest. Total carbon was analyzed in the laboratory and samples were scanned using a spectroradiometer. We found evidence that the reflectance was influenced by soil carbon content, which is consistent with the literature. However, the reflectance was not useful for building an appropriate regression model. Thus, we report here intriguing results obtained in the calibration process that can be confusing and misinterpreted. For instance, using the Savitzky–Golay filter for pre-processing spectral data, we obtained R2 = 0.82 and root-mean-squared error (RMSE) = 0.61% in model calibration. However, despite these values being comparable with those of other similar studies, in the cross-validation procedure, the data showed an unusual behavior that leads to the conclusion that the model overfits the data. This indicates that the model should not be used on unobserved data.
      PubDate: 2017-07-08
      DOI: 10.3390/app7070708
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 709: Transmission Power Determination
           Based on Power Amplifier Operations in Large-Scale MIMO-OFDM Systems

    • Authors: Byung Lee, Youngok Kim
      First page: 709
      Abstract: This paper presents a method to determine transmission power based on power amplifier (PA) operations in order to improve the energy efficiency (EE) of a large-scale (LS) Multiple Input Multiple Output (MIMO)-OFDM system, which is a multi-carrier multiple antenna system with a large amount of transmitter (TX) antennas. Regarding the EE improvement, we propose two kinds of PA operation schemes: increasing the effective TX power (ITXP) and reducing the PA power consumption (RPC) assuming that a reduction of peak-to-average power ratio is applied in the appropriate manner. Closed-form expressions of relative EE are derived for both schemes, and the relative EE of the ITXP scheme is shown to depend on the precoding method that is applied to reduce the inter-user interference, while that of the RPC scheme is independent of the precoding method. The relative EE difference between the ITXP and the RPC schemes is also shown to rely on the occupation ratio of the PA power consumption over the total power consumption. Thus, the EE can remarkably improve by selecting the appropriate scheme based on the circumstances. The results of a simulation also validate the derived closed-form expression of the relative EE.
      PubDate: 2017-07-09
      DOI: 10.3390/app7070709
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 710: Fabricating High-Quality 3D-Printed
           Alloys for Dental Applications

    • Authors: Min-Ho Hong, Bong Min, Tea-Yub Kwon
      First page: 710
      Abstract: Metal additive manufacturing (AM), especially selective laser melting (SLM), has been receiving particular attention because metallic functional structures with complicated configurations can be effectively fabricated using the technique. However, there still exist some future challenges for the fabrication of high-quality SLM products for dental applications. First, the surface quality of SLM products should be further improved by standardizing the laser process parameters or by appropriately post-treating the surface. Second, it should be guaranteed that dental SLM restorations have good dimensional accuracy and, in particular, a good marginal fit. Third, a definitive standard regarding building and scanning strategies, which affect the anisotropy, should be established to optimize the mechanical properties and fatigue resistance of SLM dental structures. Fourth, the SLM substructure’s bonding and support to veneering ceramic should be further studied to facilitate the use of esthetic dental restorations. Finally, the biocompatibility of SLM dental alloys should be carefully examined and improved to minimize the potential release of toxic metal ions from the alloys. Future research of SLM should focus on solving the above challenges, as well as on fabricating dental structures with “controlled” porosity.
      PubDate: 2017-07-10
      DOI: 10.3390/app7070710
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 711: Experimental Study of Vibration
           Isolation Characteristics of a Geometric Anti-Spring Isolator

    • Authors: Lixun Yan, Xinglong Gong
      First page: 711
      Abstract: In order to realize low-frequency vibration isolation, a novel geometric anti-spring isolator consisting of several cantilever blade springs are developed in this paper. The optimal design parameters of the geometric anti-spring isolator for different nonlinear geometric parameters are theoretically obtained. The transmissibility characteristic of the geometric anti-spring isolator is investigated through mathematical simulation. A geometric anti-spring isolator with a nonlinear geometric parameter of 0.92 is designed and its vibration isolation performance and nonlinearity characteristic is experimentally studied. The experiment results show that the designed isolator has good low-frequency vibration isolation performance, of which the initial isolation frequency is less than 3.6 Hz when the load weight is 21 kg. The jump phenomena of the response of the isolator under linear frequency sweep excitation are observed, and this result demonstrates that the geometric anti-spring isolator has a complex nonlinearity characteristics with the increment of excitation amplitude. This research work provides a theoretical and experimental basis for the application of the nonlinear geometric anti-spring low-frequency passive vibration isolation technology in engineering practice.
      PubDate: 2017-07-10
      DOI: 10.3390/app7070711
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 712: Simulating the Effects of the
           Airborne Lidar Scanning Angle, Flying Altitude, and Pulse Density for
           Forest Foliage Profile Retrieval

    • Authors: Haiming Qin, Cheng Wang, Xiaohuan Xi, Jianlin Tian, Guoqing Zhou
      First page: 712
      Abstract: Foliage profile is a key biophysical parameter for forests. Airborne Light Detection and Ranging is an effective tool for vegetation parameter retrieval. Data acquisition conditions influence the estimation of biophysical parameters. To acquire accurate foliage profiles at the lowest cost, we used simulations to explore the effects of data acquisition conditions on forest foliage profile retrieval. First, a 3-D forest scene and the airborne small-footprint full-waveform LiDAR data were simulated by the DART model. Second, the foliage profile was estimated from LiDAR data based on a Geometric Optical and Radiative Transfer model. Lastly, the effects of the airborne LiDAR scanning angle, flying altitude, and pulse density on foliage profile retrieval were explored. The results indicated that the scanning angle was an important factor in the foliage profile retrieval, and the optimal scanning angle was 20°. The optimal scanning angle was independent of flying altitude and pulse density, and combinations of multiple scanning angles could improve the accuracy of the foliage profile estimation. The flying altitude and pulse density had little influence on foliage profile retrieval at plot level and could be ignored. In general, our study provides reliable information for selecting the optimal instrument operational parameters to acquire more accurate foliage profiles and minimize data acquisition costs.
      PubDate: 2017-07-10
      DOI: 10.3390/app7070712
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 713: On the Delayed Scaled Consensus
           Problems

    • Authors: Yilun Shang
      First page: 713
      Abstract: In this note, we study the scaled consensus (tracking) problems, wherein all agents reach agreement, but with different assigned ratios in the asymptote. Based on the nearest neighbor-interaction rules, the scaled consensus processes are characterized with and without time delay. We consider both the signal transmission and signal processing delays and calculate the final scaled consensus values. When the underlying communication network contains a spanning tree, it is found that the scaled consensus can be achieved independent of the transmission delays while the specified consensus values in the asymptote depend on the initial history of the agents over a period of time. This phenomenon is in sharp contrast to the case of processing delays, where large delays are likely to jeopardize the consensus behavior, but the scaled consensus values once achieved are the same as the undelayed case.
      PubDate: 2017-07-11
      DOI: 10.3390/app7070713
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 714: Member Discrete Element Method for
           Static and Dynamic Responses Analysis of Steel Frames with Semi-Rigid
           Joints

    • Authors: Jihong Ye, Lingling Xu
      First page: 714
      Abstract: In this paper, a simple and effective numerical approach is presented on the basis of the Member Discrete Element Method (MDEM) to investigate static and dynamic responses of steel frames with semi-rigid joints. In the MDEM, structures are discretized into a set of finite rigid particles. The motion equation of each particle is solved by the central difference method and two adjacent arbitrarily particles are connected by the contact constitutive model. The above characteristics means that the MDEM is able to naturally handle structural geometric nonlinearity and fracture. Meanwhile, the computational framework of static analysis is consistent with that of dynamic analysis, except the determination of damping. A virtual spring element with two particles but without actual mass and length is used to simulate the mechanical behaviors of semi-rigid joints. The spring element is not directly involved in the calculation, but is employed only to modify the stiffness coefficients of contact elements at the semi-rigid connections. Based on the above-mentioned concept, the modified formula of the contact element stiffness with consideration of semi-rigid connections is deduced. The Richard-Abbort four-parameter model and independent hardening model are further introduced accordingly to accurately capture the nonlinearity and hysteresis performance of semi-rigid connections. Finally, the numerical approach proposed is verified by complex behaviors of steel frames with semi-rigid connections such as geometric nonlinearity, snap-through buckling, dynamic responses and fracture. The comparison of static and dynamic responses obtained using the modified MDEM and those of the published studies illustrates that the modified MDEM can simulate the mechanical behaviors of semi-rigid connections simply and directly, and can accurately effectively capture the linear and nonlinear behaviors of semi-rigid connections under static and dynamic loading. Some conclusions, as expected, are drawn that structural bearing capacity under static loading will be overestimated if semi-rigid connections are ignored; when the frequency of dynamic load applied is close to structural fundamental frequency, hysteresis damping of nonlinear semi-rigid connections can cause energy dissipation compared to rigid and linear semi-rigid connections, thus avoiding the occurrence of resonance. Additionally, fracture analysis also indicates that semi-rigid steel frames possess more anti-collapse capacity than that with rigid steel frames.
      PubDate: 2017-07-11
      DOI: 10.3390/app7070714
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 715: Reduction of Hexavalent Chromium
           Using Sorbaria sorbifolia Aqueous Leaf Extract

    • Authors: Shashi Dubey, Mika Sillanpaa, Rajender Varma
      First page: 715
      Abstract: Aqueous plant leaves extract (PLE) of an abundant shrub, Sorbaria sorbifolia, was explored for the reduction of hexavalent chromium, Cr(VI), to trivalent chromium, Cr(III). The effect of contact time, pH, PLE quantity, ionic strength, hardness, temperature and effective initial Cr(VI) ion concentration were tested; Cr(VI) reduction followed the pseudo-first order rate kinetics and maximum reduction was observed at pH 2. Significantly, Cr(VI) reduction efficacies varied from 97 to 66% over the pH range of 2 to 10, which bodes well for PLE to be used for the reduction of Cr(VI) also at a higher pH. PLE-mediated Cr(VI) reduction displays considerable efficiency at various ionic strengths; however, hardness strongly affects the reduction ability. Higher temperature significantly enhances the Cr(VI) reduction. This study reveals the potential use of PLE as a green reducing agent in aqueous extract for the efficient reduction of Cr(VI) to Cr(III).
      PubDate: 2017-07-11
      DOI: 10.3390/app7070715
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 716: Numerical Study on Dynamic Response
           of a Horizontal Layered-Structure Rock Slope under a Normally Incident Sv
           Wave

    • Authors: Zhifa Zhan, Shengwen Qi
      First page: 716
      Abstract: Several post-earthquake investigations have indicated that the slope structure plays a leading role in the stability of rock slopes under dynamic loads. In this paper, the dynamic response of a horizontal layered-structure rock slope under harmonic Sv wave is studied by making use of the Fast Lagrangian Analysis of Continua method (FLAC). The suitability of FLAC for studying wave transmission across rock joints is validated through comparison with analytical solutions. After parametric studies on Sv wave transmission across the horizontal layered-structure rock slope, it is found that the acceleration amplification coefficient η, which is defined as the ratio of the acceleration at the monitoring point to the value at the toe, wavily increases with an increase of the height along the slope surface. Meanwhile, the fluctuation weakens with normalized joint stiffness K increasing and enhances with normalized joint spacing ξ increasing. The acceleration amplification coefficient of the slope crest ηcrest does not monotonously increase with the increase of ξ, but decreases with the increase of K. Additionally, ηcrest is more sensitive to ξ compared to K. From the contour figures, it can also be found that the contour figures of η take on rhythm, and the effects of ξ on the acceleration amplification coefficient are more obvious compared to the effects on K.
      PubDate: 2017-07-11
      DOI: 10.3390/app7070716
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 717: Investigation into the Vibrational
           Responses of Cylinder Liners in an IC Engine Fueled with Biodiesel

    • Authors: Guoxing Li, Fengshou Gu, Tie Wang, Jianjun You, Andrew Ball
      First page: 717
      Abstract: The paper presents a study of the relationship between the combustion behavior and vibration response of internal combustion (IC) engines fueled with biodiesel based on finite element modelling along with experimental evaluation. An improved finite element (FE) model is established and validated to predict the dynamic responses of cylinder liners with respect to two main sources: combustion shock and piston side thrust. Based on the validated FE model, the response characteristics of the cylinder liner in an IC engine fueled with biodiesel and its causal relationship with excitation sources have been predicted. Due to the lower calorific value of biodiesel, a greater amount of fuel is injected into the combustion chamber to maintain power outputs, which results in a prolonged combustion duration and subsequent higher overall vibration levels, compared with that of diesel. The advanced ignition of biodiesel is the main cause to the compound effect on the coupling of piston side-thrust force, thereby resulting in a nonlinear increase in the root mean square (RMS) of local vibration response close to the combustion top dead center (TDC). These key findings provides insight understandings for not only biodiesel combustion diagnostics but also more accurate diagnostics of fossil diesel based on nonintrusive vibrations.
      PubDate: 2017-07-13
      DOI: 10.3390/app7070717
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 718: Permeability and Stiffness Assessment
           of Paved and Unpaved Roads with Geocomposite Drainage Layers

    • Authors: Cheng Li, Jeramy Ashlock, David White, Pavana Vennapusa
      First page: 718
      Abstract: Poor subsurface drainage is frequently identified as a factor leading to the accelerated damage of roadway systems. Geocomposite drainage layers offer an alternative to traditional methods but have not been widely evaluated, especially in terms of the impact of changes on both drainage capacity and stiffness. In this study, both paved and unpaved test sections with and without an embedded geocomposite drainage layer were constructed and tested. The geocomposite layers were installed directly beneath the roadway surface layers to help the rapid drainage of any infiltrated water and thus prevent water entering the underlying foundation materials. The laboratory, field, and numerical analysis results showed that the geocomposite layers increased the permeability of roadway systems by two to three orders of magnitude and that it can effectively prevent the surface and foundation materials from becoming saturated during heavy rainfall events. For the stiffness of the sections, the paved sections with and without a geocomposite layer showed that the composite modulus values measured at the surface were more reflective of the foundation layer support conditions beneath the geocomposite layer than the geocomposite layer itself. The unpaved road section with the geocomposite layer yielded lower composite modulus values than the control section but showed overall better road surface conditions after a rain event due to the improved subsurface drainage condition.
      PubDate: 2017-07-13
      DOI: 10.3390/app7070718
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 719: Analysis on the Accuracy of Intraoral
           Scanners: The Effects of Mandibular Anterior Interdental Space

    • Authors: Ji-hye Chun, Ji Tahk, Youn-Sic Chun, Ji-Man Park, Minji Kim
      First page: 719
      Abstract: In this study, we evaluated the effects of mandibular anterior interdental space on the accuracy of intraoral scanners. Four models of mandibular arch with varying distances of anterior interdental space were analyzed; incisors were evenly spaced out between the two canines by 0 mm, 1 mm, 3 mm, and 5 mm. The full arch of each model was scanned 10 times with iTero® and Trios®. The images were superimposed with those from the reference scanner (Sensable S3) and compared using Geomagic Verify. Statistical analysis was conducted using a t-test, paired t-test, and one-way analysis of variance (ANOVA). Differences in the accuracy of images were statistically significant according to both iTero® and Trios®; a greater deviation was noted with increasing anterior interdental space (p < 0.05). Upon dividing the lower arch into five sections, larger deviation was observed with iTero® in the molar area, except in the model with 1 mm space. With Trios®, the largest deviation was observed in the right molar area in all models. The maximum deviations of intermolar width were 0.66 mm and 0.76 mm in iTero® and Trios®, respectively. This comparison suggests that Trios® demonstrates a higher accuracy than iTero® in all models and in all sections of the arch. However, the mean deviations indicate that both iTero® and Trios® are clinically acceptable.
      PubDate: 2017-07-13
      DOI: 10.3390/app7070719
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 720: SwissFEL: The Swiss X-ray Free
           Electron Laser

    • Authors: Christopher Milne, Thomas Schietinger, Masamitsu Aiba, Arturo Alarcon, Jürgen Alex, Alexander Anghel, Vladimir Arsov, Carl Beard, Paul Beaud, Simona Bettoni, Markus Bopp, Helge Brands, Manuel Brönnimann, Ingo Brunnenkant, Marco Calvi, Alessandro Citterio, Paolo Craievich, Marta Csatari Divall, Mark Dällenbach, Michael D’Amico, Andreas Dax, Yunpei Deng, Alexander Dietrich, Roberto Dinapoli, Edwin Divall, Sladana Dordevic, Simon Ebner, Christian Erny, Hansrudolf Fitze, Uwe Flechsig, Rolf Follath, Franziska Frei, Florian Gärtner, Romain Ganter, Terence Garvey, Zheqiao Geng, Ishkhan Gorgisyan, Christopher Gough, Andreas Hauff, Christoph Hauri, Nicole Hiller, Tadej Humar, Stephan Hunziker, Gerhard Ingold, Rasmus Ischebeck, Markus Janousch, Pavle Juranić, Mario Jurcevic, Maik Kaiser, Babak Kalantari, Roger Kalt, Boris Keil, Christoph Kittel, Gregor Knopp, Waldemar Koprek, Henrik Lemke, Thomas Lippuner, Daniel Llorente Sancho, Florian Löhl, Carlos Lopez-Cuenca, Fabian Märki, Fabio Marcellini, Goran Marinkovic, Isabelle Martiel, Ralf Menzel, Aldo Mozzanica, Karol Nass, Gian Orlandi, Cigdem Ozkan Loch, Ezequiel Panepucci, Martin Paraliev, Bruce Patterson, Bill Pedrini, Marco Pedrozzi, Patrick Pollet, Claude Pradervand, Eduard Prat, Peter Radi, Jean-Yves Raguin, Sophie Redford, Jens Rehanek, Julien Réhault, Sven Reiche, Matthias Ringele, Jochen Rittmann, Leonid Rivkin, Albert Romann, Marie Ruat, Christian Ruder, Leonardo Sala, Lionel Schebacher, Thomas Schilcher, Volker Schlott, Thomas Schmidt, Bernd Schmitt, Xintian Shi, Markus Stadler, Lukas Stingelin, Werner Sturzenegger, Jakub Szlachetko, Dhanya Thattil, Daniel Treyer, Alexandre Trisorio, Wolfgang Tron, Seraphin Vetter, Carlo Vicario, Didier Voulot, Meitian Wang, Thierry Zamofing, Christof Zellweger, Riccardo Zennaro, Elke Zimoch, Rafael Abela, Luc Patthey, Hans-Heinrich Braun
      First page: 720
      Abstract: The SwissFEL X-ray Free Electron Laser (XFEL) facility started construction at the Paul Scherrer Institute (Villigen, Switzerland) in 2013 and will be ready to accept its first users in 2018 on the Aramis hard X-ray branch. In the following sections we will summarize the various aspects of the project, including the design of the soft and hard X-ray branches of the accelerator, the results of SwissFEL performance simulations, details of the photon beamlines and experimental stations, and our first commissioning results.
      Citation: Applied Sciences
      PubDate: 2017-07-14
      DOI: 10.3390/app7070720
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 721: The New Concept of Nano-Device
           Spectroscopy Based on Rabi–Bloch Oscillations for THz-Frequency Range

    • Authors: Ilay Levie, Gregory Slepyan
      First page: 721
      Abstract: We considered one-dimensional quantum chains of two-level Fermi particles coupled via the tunneling driven both by ac and dc fields in the regimes of strong and ultrastrong coupling. The frequency of ac field is matched with the frequency of the quantum transition. Based on the fundamental principles of electrodynamics and quantum theory, we developed a general model of quantum dynamics for such interactions. We showed that the joint action of ac and dc fields leads to the strong mutual influence of Rabi- and Bloch oscillations, one to another. We focused on the regime of ultrastrong coupling, for which Bloch- and Rabi-frequencies are significant values of the frequency of interband transition. The Hamiltonian was solved numerically, with account of anti-resonant terms. It manifests by the appearance of a great number of narrow high-amplitude resonant lines in the spectra of tunneling current and dipole moment. We proposed the new concept of terahertz (THz) spectroscopy, which is promising for different applications in future nanoelectronics and nano-photonics.
      Citation: Applied Sciences
      PubDate: 2017-07-14
      DOI: 10.3390/app7070721
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 722: Phase Change Material Selection for
           Thermal Processes Working under Partial Load Operating Conditions in the
           Temperature Range between 120 and 200 °C

    • Authors: Jaume Gasia, Marc Martin, Aran Solé, Camila Barreneche, Luisa Cabeza
      First page: 722
      Abstract: In some processes, latent heat thermal energy storage (TES) systems might work under partial load operating conditions (the available thermal energy source is discontinuous or insufficient to completely charge the phase change material (PCM)). Therefore, there is a need to study how these conditions affect the discharge process to design a control strategy that can benefit the user of these systems. The aim of this paper is to show and perform at laboratory scale the selection of a PCM, with a phase change temperature between 120 and 200 °C, which will be further used in an experimental facility. Beyond the typical PCM properties, sixteen PCMs are studied here from the cycling and thermal stability point of view, as well as from the health hazard point of view. After 100 melting and freezing cycles, seven candidates out of the sixteen present a suitable cycling stability behaviour and five of them show a maximum thermal-stable temperature higher than 200 °C. Two final candidates for the partial loads approach are found in this temperature range, named high density polyethylene (HDPE) and adipic acid.
      Citation: Applied Sciences
      PubDate: 2017-07-14
      DOI: 10.3390/app7070722
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 723: Comparison of Microencapsulated Phase
           Change Materials Prepared at Laboratory Containing the Same Core and
           Different Shell Material

    • Authors: Jessica Giro-Paloma, Cemil Alkan, Josep Chimenos, Ana Fernández
      First page: 723
      Abstract: Microencapsulated Phase Change Materials (MPCM) are widely used in active and passive systems for thermal energy storage. To evaluate the strength of a proper shell/PCM system, comparisons were performed between laboratory-prepared MPCM samples produced by in situ polymerization with a phase change temperature of 50 °C and a particle size of around 1–2 μm with tetracosane as PCM, and polystyrene (PS) and poly (methyl methacrylate) (PMMA) as shells. Evaluation of mechanical performance was performed for different samples by means of Atomic Force Microscopy (AFM) at different temperatures (23 °C and 60 °C) and with different encapsulation ratios (1:3 and 1:1, shell:core) in order to compare their properties with the PCM below and above its phase change. Evaluations of the Effective Young’s modulus (E) and deformation properties were performed for both types of MPCM. For an encapsulation mass ratio of 1:3, PS has better mechanical properties because, when increasing the temperature, the E decreases less than with PMMA. In the comparison between PS/tetracosane systems with different encapsulation mass ratios (1:3 and 1:1), E values were higher for the 1:3 encapsulation mass ratio at both temperatures under study. This means that, in terms of mechanical and thermal properties, the best combination core/shell/encapsulation mass ratio is PS/tetracosane/1:3.
      Citation: Applied Sciences
      PubDate: 2017-07-14
      DOI: 10.3390/app7070723
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 724: Calculation of the Center of Mass
           Position of Each Link of Multibody Biped Robots

    • Authors: Giovanni Muscolo, Darwin Caldwell, Ferdinando Cannella
      First page: 724
      Abstract: In this paper, a novel method to determine the center of mass position of each link of human-like multibody biped robots is proposed. A first formulation to determine the total center of mass position has been tested in other works on a biped platform with human-like dimensions. In this paper, the formulation is optimized and extended, and it is able to give as output the center of mass positions of each link of the platform. The calculation can be applied to different types of robots. The optimized formulation is validated using a simulated biped robot in MATLAB.
      Citation: Applied Sciences
      PubDate: 2017-07-14
      DOI: 10.3390/app7070724
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 725: Broadening of Light Coupling to
           Waveguide Modes in Solar Cells by Disordered Grating Textures

    • Authors: Karsten Bittkau, André Hoffmann, Ulrich Paetzold, Reinhard Carius
      First page: 725
      Abstract: We investigated the light coupling to waveguide modes in nanophotonic thin-film solar cells exhibiting a tailored disordered grating texture by rigorous optical simulations. Such disordered nanophotonic light trapping concepts have demonstrated enhanced short-circuit current density compared to ordered nanophotonic thin-film solar cells. This observation is commonly explained by a spectral broadening of the resonant light coupling to waveguide modes. In this work, we investigated the origin of this spectral broadening. We identified two basic mechanisms that lead to a spectral broadening of the light coupling to waveguide modes: (1) the broadening of the wave vector transferred by the disordered interface texture and (2) the broadening of the waveguide mode due to the distortion of the wave guiding absorber layer. Depending on the type of disorder, the contribution from each of the mechanisms varies.
      Citation: Applied Sciences
      PubDate: 2017-07-15
      DOI: 10.3390/app7070725
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 726: Evaluating the Impact of the Sudden
           Collapse of Major Freeway Connectors on Rapid Transit and Adjacent Freeway
           Systems: San Francisco Bay Area Case Study

    • Authors: Yoonseok Oh, Koohong Chung, Shin Park, Cheolsun Kim, Seungmo Kang
      First page: 726
      Abstract: The early Sunday morning collapse of two sections of the multi-level freeway interchange, known as the MacArthur Maze, resulted in a month-long closure of the interchange, which connects several major California cities: San Francisco, Oakland, and Berkeley. This paper evaluates the impacts of this unplanned, extended closure on Bay Area Rapid Transit (BART) and the remaining freeway system based on empirical data and reports on the findings. Among the findings were that BART was instrumental in keeping commuters moving during the freeway repair. In addition, ridership counts at some stations remained significantly elevated after the repairs were completed. This may be due to the fact that many of the riders using those BART stations had not previously traveled via transit and, having discovered its convenience and benefits during the repair phase, continued to use BART even after the repairs. The impact of the closure on BART demand was not uniform across the stations.
      Citation: Applied Sciences
      PubDate: 2017-07-15
      DOI: 10.3390/app7070726
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 727: Special Issue on Advances in
           Integrated Energy Systems Design, Control and Optimization

    • Authors: Amjad Anvari-Moghaddam, Josep Guerrero
      First page: 727
      Abstract: In the face of climate change and resource scarcity, energy supply systems are on the verge of a major transformation, which mainly includes the introduction of new components and their integration into the existing infrastructures, new network configurations and reliable topologies, optimal design and novel operation schemes, and new incentives and business models. This revolution is affecting the current paradigm and demanding that energy systems be integrated into multi-carrier energy hubs [1]. [...]
      Citation: Applied Sciences
      PubDate: 2017-07-16
      DOI: 10.3390/app7070727
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 728: Effects of Radial Gap Ratio between
           Impeller and Vaned Diffuser on Performance of Centrifugal Compressors

    • Authors: Mohammadjavad Hosseini, Zhenzhong Sun, Xiao He, Xinqian Zheng
      First page: 728
      Abstract: A high-performance centrifugal compressor is needed for numerous industry applications nowadays. The radial gap ratio between the impeller and the diffuser vanes plays an important role in the improvement of the compressor performance. In this paper, the effects of the radial gap ratio on a high-pressure ratio centrifugal compressor are investigated using numerical simulations. The performance and the flow field are compared for six different radial gap ratios and five rotational speeds. The minimal radial gap ratio was 1.04 and the maximal was 1.14. Results showed that reducing the radial gap ratio decreases the choke mass flow rate. For the tip-speed Mach number (impeller inlet) with Mu < 1, the pressure recovery and the loss coefficients are not sensitive to the radial gap ratio. However, for Mu ≥ 1, the best radial gap ratio is 1.08 for the pressure recovery and the loss coefficients. Furthermore, the impeller pressure ratio and efficiency are reduced by increasing the radial gap ratio. Finally, the compressor efficiency was compared for different radial gap ratios. For Mu < 1, the radial gap ratio does not have noticeable effects. In comparison, the radial gap ratio of 1.08 has the best performance for Mu ≥ 1.
      Citation: Applied Sciences
      PubDate: 2017-07-16
      DOI: 10.3390/app7070728
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 729: Data-Foraging-Oriented Reconnaissance
           Based on Bio-Inspired Indirect Communication for Aerial Vehicles

    • Authors: Josué Castañeda Cisneros, Saul E. Pomares Hernandez, Jose Roberto Perez Cruz, Lil María Rodríguez-Henríquez, Jesus A. Gonzalez Bernal
      First page: 729
      Abstract: In recent years, aerial vehicles have allowed exploring scenarios with harsh conditions. These can conduct reconnaissance tasks in areas that change periodically and have a high spatial and temporal resolution. The objective of a reconnaissance task is to survey an area and retrieve strategic information. The aerial vehicles, however, have inherent constraints in terms of energy and transmission range due to their mobility. Despite these constraints, the Data Foraging problem requires the aerial vehicles to exchange information about profitable data sources. In Data Foraging, establishing a single path is not viable because of dynamic conditions of the environment. Thus, reconnaissance must be focused on periodically searching profitable environmental data sources, as some animals perform foraging. In this work, a data-foraging-oriented reconnaissance algorithm based on bio-inspired indirect communication for aerial vehicles is presented. The approach establishes several paths that overlap to identify valuable data sources. Inspired by the stigmergy principle, the aerial vehicles indirectly communicate through artificial pheromones. The aerial vehicles traverse the environment using a heuristic algorithm that uses the artificial pheromones as feedback. The solution is formally defined and mathematically evaluated. In addition, we show the viability of the algorithm by simulations which have been tested through various statistical hypothesis.
      Citation: Applied Sciences
      PubDate: 2017-07-16
      DOI: 10.3390/app7070729
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 730: Optimized Neural Architecture for
           Automatic Landslide Detection from High‐Resolution Airborne Laser
           Scanning Data

    • Authors: Mustafa Ridha Mezaal, Biswajeet Pradhan, Maher Ibrahim Sameen, Helmi Zulhaidi Mohd Shafri, Zainuddin Md Yusoff
      First page: 730
      Abstract: An accurate inventory map is a prerequisite for the analysis of landslide susceptibility, hazard, and risk. Field survey, optical remote sensing, and synthetic aperture radar techniques are traditional techniques for landslide detection in tropical regions. However, such techniques are time consuming and costly. In addition, the dense vegetation of tropical forests complicates the generation of an accurate landslide inventory map for these regions. Given its ability to penetrate vegetation cover, high-resolution airborne light detection and ranging (LiDAR) has been used to generate accurate landslide maps. This study proposes the use of recurrent neural networks (RNN) and multi-layer perceptron neural networks (MLP-NN) in landscape detection. These efficient neural architectures require little or no prior knowledge compared with traditional classification methods. The proposed methods were tested in the Cameron Highlands, Malaysia. Segmentation parameters and feature selection were respectively optimized using a supervised approach and correlation-based feature selection. The hyper-parameters of network architecture were defined based on a systematic grid search. The accuracies of the RNN and MLP-NN models in the analysis area were 83.33% and 78.38%, respectively. The accuracies of the RNN and MLP-NN models in the test area were 81.11%, and 74.56%, respectively. These results indicated that the proposed models with optimized hyper-parameters produced the most accurate classification results. LiDAR-derived data, orthophotos, and textural features significantly affected the classification results. Therefore, the results indicated that the proposed methods have the potential to produce accurate and appropriate landslide inventory in tropical regions such as Malaysia.
      Citation: Applied Sciences
      PubDate: 2017-07-16
      DOI: 10.3390/app7070730
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 731: A Review on Nanocomposite Materials
           for Rechargeable Li-ion Batteries

    • Authors: Dervis Demirocak, Sesha Srinivasan, Elias Stefanakos
      First page: 731
      Abstract: Li-ion batteries are the key enabling technology in portable electronics applications, and such batteries are also getting a foothold in mobile platforms and stationary energy storage technologies recently. To accelerate the penetration of Li-ion batteries in these markets, safety, cost, cycle life, energy density and rate capability of the Li-ion batteries should be improved. The Li-ion batteries in use today take advantage of the composite materials already. For instance, cathode, anode and separator are all composite materials. However, there is still plenty of room for advancing the Li-ion batteries by utilizing nanocomposite materials. By manipulating the Li-ion battery materials at the nanoscale, it is possible to achieve unprecedented improvement in the material properties. After presenting the current status and the operating principles of the Li-ion batteries briefly, this review discusses the recent developments in nanocomposite materials for cathode, anode, binder and separator components of the Li-ion batteries.
      Citation: Applied Sciences
      PubDate: 2017-07-17
      DOI: 10.3390/app7070731
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 732: Widely-Tunable Ring-Resonator
           Semiconductor Lasers

    • Authors: Tin Komljenovic, Linjun Liang, Rui-Lin Chao, Jared Hulme, Sudharsanan Srinivasan, Michael Davenport, John E. Bowers
      First page: 732
      Abstract: Chip-scale widely-tunable lasers are important for both communication and sensing applications. They have a number of advantages, such as size, weight, and cost compared to mechanically tuned counterparts. Furthermore, they allow for integration in more complex integrated photonic chips to realize added functionality. Here we give an extensive overview of such lasers realized by utilizing ring resonators inside the laser cavity. Use of ring resonators for tuning allows for wide-tunability by exploiting the Vernier effect, and at the same time improves the laser linewidth, as effective cavity length is increased at ring resonance. In this review, we briefly introduce basic concepts of laser tuning using ring resonators. Then, we study a number of laser cavity configurations that utilize two ring resonators, and compare their tuning performance. We introduce a third ring resonator to the laser cavity, study three different cavity configurations utilizing three ring resonators, and select the optimal one, for which we show that laser tuning is straightforward, provided there are monitor photodetectors on-chip. Finally, we give a literature overview showing superior linewidth performance of ring-based widely-tunable lasers.
      Citation: Applied Sciences
      PubDate: 2017-07-17
      DOI: 10.3390/app7070732
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 733: Development of a Modelling and
           Simulation Method for Residential Electricity Consumption Analysis in a
           Community Microgrid System

    • Authors: Yu-Jen Liu, Shang-I Chen, Yung-Ruei Chang, Yih-Der Lee
      First page: 733
      Abstract: There is an increasing number of microgrid applications for power system networks at different voltage levels. Community microgrid systems are also being encouraged in order to increase energy efficiency, reduce electricity bills, and alleviate the reliability problem with respect to power delivery for local residential users. Understanding electricity information can help in effective management and control of various energy sources operated in community microgrid systems. This paper thus aims to develop a simulation-based electricity analysis scheme for a real community microgrid configuration using a proposed modelling methodology, simulation mechanisms, and a power balancing control strategy under the MATLAB environment. Simulation results considering different weather conditions report the observed performance of electricity analysis. In addition, calculations of electricity bills depending on two electricity rates are discussed, representing the benefits of electricity bill reduction when electricity users accepted the power supply from community microgrid systems.
      Citation: Applied Sciences
      PubDate: 2017-07-17
      DOI: 10.3390/app7070733
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 734: Three Dimensional Digital Sieving of
           Asphalt Mixture Based on X-ray Computed Tomography

    • Authors: Chichun Hu, Jiexian Ma, M. Kutay
      First page: 734
      Abstract: In order to perform three-dimensional digital sieving based on X-ray computed tomography images, the definition of digital sieve size (DSS) was proposed, which was defined as the minimum length of the minimum bounding squares of all possible orthographic projections of an aggregate. The corresponding program was developed to reconstruct aggregate structure and to obtain DSS. Laboratory experiments consisting of epoxy-filled aggregate specimens were conducted to investigate the difference between mechanical sieve analysis and the digital sieving technique. It was suggested that concave surface of aggregate was the possible reason for the disparity between DSS and mechanical sieve size. A comparison between DSS and equivalent diameter was also performed. Moreover, the digital sieving technique was adopted to evaluate the gradation of stone mastic asphalt mixtures. The results showed that the closest proximity of the laboratory gradation curve was achieved by calibrated DSS, among gradation curves based on calibrated DSS, un-calibrated DSS and equivalent diameter.
      Citation: Applied Sciences
      PubDate: 2017-07-18
      DOI: 10.3390/app7070734
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 735: Seismic Vulnerability Assessment of a
           Shallow Two-Story Underground RC Box Structure

    • Authors: Jungwon Huh, Quang Tran, Achintya Haldar, Innjoon Park, Jin-Hee Ahn
      First page: 735
      Abstract: Tunnels, culverts, and subway stations are the main parts of an integrated infrastructure system. Most of them are constructed by the cut-and-cover method at shallow depths (mainly lower than 30 m) of soil deposits, where large-scale seismic ground deformation can occur with lower stiffness and strength of the soil. Therefore, the transverse racking deformation (one of the major seismic ground deformation) due to soil shear deformations should be included in the seismic design of underground structures using cost- and time-efficient methods that can achieve robustness of design and are easily understood by engineers. This paper aims to develop a simplified but comprehensive approach relating to vulnerability assessment in the form of fragility curves on a shallow two-story reinforced concrete underground box structure constructed in a highly-weathered soil. In addition, a comparison of the results of earthquakes per peak ground acceleration (PGA) is conducted to determine the effective and appropriate number for cost- and time-benefit analysis. The ground response acceleration method for buried structures (GRAMBS) is used to analyze the behavior of the structure subjected to transverse seismic loading under quasi-static conditions. Furthermore, the damage states that indicate the exceedance level of the structural strength capacity are described by the results of nonlinear static analyses (or so-called pushover analyses). The Latin hypercube sampling technique is employed to consider the uncertainties associated with the material properties and concrete cover owing to the variation in construction conditions. Finally, a large number of artificial ground shakings satisfying the design spectrum are generated in order to develop the seismic fragility curves based on the defined damage states. It is worth noting that the number of ground motions per PGA, which is equal to or larger than 20, is a reasonable value to perform a structural analysis that produces satisfactory fragility curves.
      Citation: Applied Sciences
      PubDate: 2017-07-18
      DOI: 10.3390/app7070735
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 736: Synthesis, Characterization, and
           

    • Authors: Jinran Lee, Baskaran Purushothaman, Zhao Li, Goutam Kulsi, Joon Song
      First page: 736
      Abstract: Diabetic foot ulcer (DFU) is becoming more serious concern as it affects 95% of diabetic patients worldwide. It has been shown that the Staphylococcus aureus and other Gram-negative microorganisms are the main reasons behind this disease. Though many antibiotics are presently used to treat the DFU, due to increased bacterial resistance, new alternative therapies are always welcome. To address this alarming issue, we have designed and synthesized the high-valence silver propamidine (Ag(II)PRO) complex as well as nanoparticles and characterized both by usual spectroscopic methods. The reverse microemulsion technique has been applied to synthesize Ag(II)PRO nanoparticles and its antibacterial activity has been compared with zero-valence silver nanoparticles (AgNPs) with similar size. The antibacterial efficacies of Ag(II)PRO nanoparticles and AgNPs were tested against Gram-negative and Gram -positive organisms responsible for DFU. The newly synthesized high-valence Ag(II)PRO nanoparticles showed higher antibacterial activity compared to silver-only nanoparticles (AgNPs). This study concludes that the high-valence Ag(II)PRO nanoparticles show better antibacterial activity than AgNPs and they may serve as the next generation therapeutic agent for the diabetic wound care.
      Citation: Applied Sciences
      PubDate: 2017-07-18
      DOI: 10.3390/app7070736
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 737: Elastic Wave Measurement Using a MEMS
           AE Sensor

    • Authors: Takahiro Omori, Takashi Usui, Kazuo Watabe, Minh-Dung Nguyen, Kiyoshi Matsumoto, Isao Shimoyama
      First page: 737
      Abstract: In recent years, with the continuing progress of aging social infrastructures such as bridges and tunnels, there has been high demand for the assessment of deterioration of their performance and conditions. Since current inspection methods for those structures have mainly relied on human resources, it is important to reduce their increasing maintenance cost. One of the key methods for achieving effective maintenance without expensive human costs is to use sensors to discriminate between healthy and unhealthy conditions. In this paper, a MEMS (micro electro mechanical systems) wideband frequency sensor, which is referred to as a super acoustic (SA) sensor, is evaluated through the pencil lead break (PLB) test. Due to its wideband frequency characteristics, the SA sensor is expected to be a promising alternative to the existing vibration sensors, including acoustic emission (AE) sensors. Several PLB signals were generated on an aluminum plate (5 mm thick), and propagating Lamb waves were detected by both AE and SA sensors. SA sensors were able to identify the location of PLB sources on the plate by measuring time differences between each sensor. By comparing the wave spectrums of both the AE and SA sensors analyzed by wavelet transform, the applicability of SA sensor for AE measurement is verified.
      Citation: Applied Sciences
      PubDate: 2017-07-19
      DOI: 10.3390/app7070737
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 738: Adaptive Global Fast Sliding Mode
           Control for Steer-by-Wire System Road Vehicles

    • Authors: Junaid Iqbal, Khalil Zuhaib, Changsoo Han, Abdul Khan, Mian Ali
      First page: 738
      Abstract: A steer-by-wire (SbW) system, also known as a next-generation steering system, is one of the core elements of autonomous driving technology. Navigating a SbW system road vehicle in varying driving conditions requires an adaptive and robust control scheme to effectively compensate for the uncertain parameter variations and external disturbances. Therefore, this article proposed an adaptive global fast sliding mode control (AGFSMC) for SbW system vehicles with unknown steering parameters. First, the cooperative adaptive sliding mode observer (ASMO) and Kalman filter (KF) are established to simultaneously estimate the vehicle states and cornering stiffness coefficients. Second, based on the best set of estimated dynamics, the AGFSMC is designed to stabilize the impact of nonlinear tire-road disturbance forces and at the same time to estimate the uncertain SbW system parameters. Due to the robust nature of the proposed scheme, it can not only handle the tire–road variation, but also intelligently adapts to the different driving conditions and ensures that the tracking error and the sliding surface converge asymptotically to zero in a finite time. Finally, simulation results and comparative study with other control techniques validate the excellent performance of the proposed scheme.
      Citation: Applied Sciences
      PubDate: 2017-07-19
      DOI: 10.3390/app7070738
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 739: Measurements of Thermally-Induced
           Curvatures and Warpages of Printed Circuit Board during a Solder Reflow
           Process Using Strain Gauges

    • Authors: Meng-Chieh Liao, Pu-Shan Huang, Yi-Hsien Lin, Ming-Yi Tsai, Chen-Yu Huang, Te-Chin Huang
      First page: 739
      Abstract: Measurements of the curvatures and warpages of a printed circuit board (PCB) during a thermal solder reflow process using strain gauges are proposed in this study. In the experiments, a shadow moiré is used for measuring the out-of-plane deformations (or warpage) of a bi-material plate and a PCB with dual in-line memory module (DIMM) sockets during solder reflow heating, while the finite element method (FEM) is used to analyze the thermally-induced deformation of the PCB specimen for ensuring the validity of the measurement. Conventional strain gauges are employed to measure the strains (albeit as in-plane strain data) in both specimens during the solder reflow process. The results indicate that the strain gauge-measured strain data from the top and bottom surfaces of both specimens during the solder reflow can be converted into curvature data with specific equations, and even into global out-of-plane deformations or warpages with a proposed simple beam model. Such results are also consistent with those from the shadow moiré and FEM. Therefore, it has been proved that the strain gauge measurement associated with the simple beam model can provide a method for the real-time monitoring of PCB deformations or warpages with different temperatures during the solder reflow process.
      Citation: Applied Sciences
      PubDate: 2017-07-20
      DOI: 10.3390/app7070739
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 740: Thermal Performance of Concrete with
           Recycled Aggregates from CDW Plants

    • Authors: Miguel Bravo, Jorge Brito, Luís Evangelista
      First page: 740
      Abstract: This investigation intends to analyse the thermal performance of concrete with recycled aggregates (RA) from construction and demolition waste (CDW) collected from several locations in Portugal. A total of 17 concrete mixes were analysed by means of thermal conductivity tests. Firstly, the composition and characteristics of the aggregates (natural and recycled) used in the production of the concrete mixes were analysed thoroughly, by means of several physical and chemical tests. Later, in order to evaluate the thermal behaviour of the mixes, several tests were performed and their results analysed, both on the fresh-state (slump with the Abrams cone test, density and air content) and the hardened state (compressive strength and thermal conductivity). The analysis of the thermal behaviour showed that the use of RA improves the thermal performance of the concrete mixes. The extent of this change was shown to be quite variable depending on the origin of the RA used.
      Citation: Applied Sciences
      PubDate: 2017-07-20
      DOI: 10.3390/app7070740
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 741: Application of Bender Elements
           Technique in Testing of Anthropogenic Soil—Recycled Concrete Aggregate
           and Its Mixture with Rubber Chips

    • Authors: Katarzyna Gabryś, Wojciech Sas, Emil Soból, Andrzej Głuchowski
      First page: 741
      Abstract: This paper discusses the application of piezoceramic bender elements (BEs) for measurement of shear wave velocity in the time and frequency domain in a triaxial cell under different isotropic confinement. Different interpretation methods were used in the tests and their results were finally compared with each other. Two types of anthropogenic material were tested: pure Recycled Concrete Aggregate (RCA) and RCA-rubber chips mixtures (15% of rubber addition). Presented study is an attempt to describe dynamic properties, in terms of shear wave velocity (VS), of the aforementioned anthropogenic material using the technique commonly applied for natural soil. Although some research is currently being carried out, in order to evaluate physical, chemical and mechanical properties of RCA and rubber-soil mixtures, still little is known of their dynamic properties. Hence, this work will provide the experimental results of shear wave velocity of RCA and its modified version. The results show that tires chips significantly decrease the VS values of modified RCA. They help to reduce the near field effect, but the received parameters are more incoherent. The VS values were found to be influenced by interpretation technique, mean effective stress and wave’s propagation period. The maximum VS values were obtained mostly from the frequency domain method, although time domain analysis gives the results that are more coherent.
      Citation: Applied Sciences
      PubDate: 2017-07-21
      DOI: 10.3390/app7070741
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 742: Cellular Automaton to Study the
           Impact of Changes in Traffic Rules in a Roundabout: A Preliminary Approach
           

    • Authors: Krzysztof Małecki, Jarosław Wątróbski
      First page: 742
      Abstract: The current article presents a roundabout traffic model based on cellular automata for computer simulation. The model takes into account various sizes of roundabouts, as well as various types and maximum speeds of vehicles. A realistic vehicle braking phase is presented which is adjusted to the kind of vehicle and weather conditions. It also analyses roundabout traffic options including where the various rules for entering and exiting a roundabout apply. Traffic rules are contained in respective traffic scenarios. The simulation results indicate that there is significant scope for roundabout traffic reorganisation, with a mind to increasing roundabout capacity.
      Citation: Applied Sciences
      PubDate: 2017-07-21
      DOI: 10.3390/app7070742
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 743: Laboratory Evaluation of Rejuvenating
           Agent on Reclaimed SBS Modified Asphalt Pavement

    • Authors: Jie Wang, Wei Zeng, Yongchun Qin, Songchang Huang, Jian Xu
      First page: 743
      Abstract: To evaluate the effect of rejuvenating agent on reclaimed SBS (styrene-butadiene-styrene) modified asphalt pavement (RSMAP) material, different tests of asphalt and mixtures were conducted. Firstly, the improvement effect of rejuvenating agents on the aged modified asphalt was tested at macroscopic and microscope level. Then the properties of hot mix asphalt (HMA) with different RSMAP contents (0%, 30%, 50% and 70%) were evaluated by conducting freeze-thaw split, semi-circular bending (SCB) and dynamic modulus (DM). The results indicate that rejuvenating agent can recycle the properties of aged modified asphalt effectively. The initial phase structure of the aged modified asphalt is not changed by adding rejuvenating agents. Moreover, the SBS particles area ratio of modified asphalt blends is significantly correlated with tenacity as the proportion of rejuvenating agent increases. For mixtures, RSMAP is harmful to moisture susceptibility and low-temperature cracking resistance of recycled mixture, especially with high RSMAP content. Moreover, the two properties can be improved by adding rejuvenating agents, but the recycled mixtures with high RSMAP content are not easy to recover to HMA mixture level. In general, the rejuvenating agent has an effect on the stiffness of the recycled mixture, but this is effect not obvious. When loading frequency reaches a higher value, the DM of recycled mixtures and HMA mixture tend to be consistent including high RSMAP content.
      Citation: Applied Sciences
      PubDate: 2017-07-21
      DOI: 10.3390/app7070743
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 744: Performance Analysis of a Burst
           Transmission Mechanism Using Microsleep Operation for Green IEEE 802.11
           WLANs

    • Authors: Raul Palacios-Trujillo, Nelson Fonseca, Jesus Alonso-Zarate, Fabrizio Granelli
      First page: 744
      Abstract: This paper evaluates the performance of a burst transmission mechanism using microsleep operation to support high energy efficiency in IEEE 802.11 Wireless Local Area Networks (WLANs). This mechanism is an implementation of the IEEE 802.11ac Transmission Opportunity Power Save Mode (TXOP PSM). A device using the TXOP PSM-based mechanism can switch to a low-power sleep state for the time that another device transmits a burst of data frames to a third one. This operation is called microsleep and its feasibility strongly depends on the time and energy consumption that a device incurs in the transitions from and to the sleep state. This paper accounts for the impact of these transitions in the derivation of an analytical model to calculate the energy efficiency of the TXOP PSM-based mechanism under network saturation. Results obtained show that the impact of the transition requirements on the feasibility of microsleep operation can be significant depending on the selected system parameters, although it can be reduced by using burst transmissions. When microsleep operation is feasible, the TXOP PSM-based mechanism can improve the energy efficiency of other legacy mechanisms by up to 424% under high traffic loads.
      Citation: Applied Sciences
      PubDate: 2017-07-21
      DOI: 10.3390/app7070744
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 745: Study of Surfactant Additives for the
           Manufacture of Warm Mix Asphalt: From Laboratory Design to Asphalt Plant
           Manufacture

    • Authors: Miguel Sol-Sánchez, Fernando Moreno-Navarro, Ma Rubio-Gámez
      First page: 745
      Abstract: Warm Mix Asphalt (WMA), manufactured at a lower temperature than the traditional Hot Mix Asphalt (HMA), allows for important economic and environmental benefits when considered for application in roads. Nonetheless, despite the benefits, its application in pavement for roads is not as widespread as desired from an environmental point of view; more in-depth studies to investigate its development and wider applicability are required. Thus, the present paper aims to contribute to the implementation of this cleaner technology to produce WMA (based on chemical additives) for its application in pavement for roads, including from the stage of the design of the material in the laboratory (by selecting the most appropriate manufacturing temperature and additive type and dosage) to its production in a conventional industrial plant for its use in a trial section. Results demonstrate that it is possible to reduce the manufacturing temperature of asphalt mixtures by using chemical additives, recording similar mechanical behaviour (or even superior) to conventional hot mixtures when specific studies are developed for the optimal design of the WMA. It was also shown that these mixtures could be produced in a conventional asphalt plant without implementing important changes in equipment, which implies a cost-effective solution that can readily be incorporated into traditional plant procedures.
      Citation: Applied Sciences
      PubDate: 2017-07-21
      DOI: 10.3390/app7070745
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 746: Aspect Ratio Evolution in Embedded,
           Surface, and Corner Cracks in Finite-Thickness Plates under Tensile
           Fatigue Loading

    • Authors: Jesús Toribio, Juan-Carlos Matos, Beatriz González
      First page: 746
      Abstract: This article deals with the computational modelling of the fatigue crack aspect ratio evolution in embedded, surface, and corner cracks located in finite-thickness plates under tensile fatigue. The approach is based on the Paris law for fatigue propagation and an expression for the stress intensity factor (SIF) provided by Newman and Raju. Numerical results indicate that the crack path develops in such a manner that all flaws tend to reach similar aspect ratios, i.e., a preferential crack path does exist along which there is a one-to-one relationship between the aspect ratio and the relative crack depth (a sort of master curve in the matter of fatigue crack path evolution). Such a reference curve corresponds to that of a very superficial initial flaw with almost circular shape. The convergence (quicker or slower approach between fatigue crack paths starting from different initial defects) is higher for surface flaws than for corner cracks, and quicker for the latter than for embedded discontinuities. Corner defects increase their size faster than surface cracks, and the latter do the same quicker than the embedded ones.
      Citation: Applied Sciences
      PubDate: 2017-07-21
      DOI: 10.3390/app7070746
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 747: A New Method for Haul Road Design in
           Open-Pit Mines to Support Efficient Truck Haulage Operations

    • Authors: Jieun Baek, Yosoon Choi
      First page: 747
      Abstract: The design of a haul road for an open-pit mine can significantly affect the cost associated with hauling ore and waste to the surface. This study proposes a new method for haul road design in open-pit mines to support efficient truck haulage operations. The road layout in open-pit mines was optimized by using raster-based least-cost path analysis, and the resulting zigzag road sections were simplified by applying the Douglas-Peucker algorithm. In addition, the road layout was modified by reflecting the radius of curvature suggested in the road design guides. Finally, a three-dimensional model reflecting the results of the road design was created by combining the road layout modification result with the slope of the open-pit mine and the bench design result. The application of the proposed method to an area containing gold deposits made it possible to design a haul road for open-pit mines such that it supported efficient truck haulage operations; furthermore, the time required for truck movement along the road could be estimated. The proposed method is expected to be useful for planning and designing open-pit mines and to facilitate the improvement of the road design function of existing mining software applications.
      Citation: Applied Sciences
      PubDate: 2017-07-23
      DOI: 10.3390/app7070747
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 749: Ideal Operation of a Photovoltaic
           Power Plant Equipped with an Energy Storage System on Electricity Market

    • Authors: Markku Järvelä, Seppo Valkealahti
      First page: 749
      Abstract: There is no natural inertia in a photovoltaic (PV) generator and changes in irradiation can be seen immediately at the output power. Moving cloud shadows are the dominant reason for fast PV power fluctuations taking place typically within a minute between 20 to 100% of the clear sky value roughly 100 times a day, on average. Therefore, operating a utility scale grid connected PV power plant is challenging. Currently, in many regions, renewable energy sources such as solar and wind receive feed-in tariffs that ensure a certain price for the energy. On the other hand, electricity markets operate on a supply-demand principle and a typical imbalance settlement period is one hour. This paper presents the energy, power and corresponding requirements for an energy storage system in a solar PV power plant to feed the power to the grid meeting the electricity spot markets practices. An ideal PV energy production forecast is assumed to be available to define reference powers of the system for the studied imbalance settlement periods. The analysis is done for three different PV system sizes using the existing irradiance measurements of the Tampere University of Technology solar PV power station research plant.
      Citation: Applied Sciences
      PubDate: 2017-07-23
      DOI: 10.3390/app7070749
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 750: Enhanced Adaptive Filtering Algorithm
           Based on Sliding Mode Control for Active Vibration Rejection of Smart Beam
           Structures

    • Authors: Byeongil Kim, Jong-yun Yoon
      First page: 750
      Abstract: This article investigates vibration rejection for a continuous smart structure using piezoelectric bimorph patches. Such a structure has inherent nonlinearities, such as hysteresis and creep, and the whole system may experience unexpected disturbances, uncertainties, and noise from external sources. Thus, it is very important to design the active control scheme carefully with adaptive filtering systems to deal with these conditions. An advanced adaptive filtering algorithm was developed based on the conventional least mean squares (LMS) method and sliding mode control for the active vibration rejection system. The sliding mode controller is applied to the standard LMS algorithm to overcome problems with misadjustment and excess error in an optimal manner. A numerical analysis and laboratory experiment show that the technique can significantly attenuate the vibration of the smart structure at different levels and broadband frequency spectra. In addition, unidentified impedance is chosen to change the distribution of the mass, and the robustness and the adaptivity of the proposed approach are verified. The experimental results show that the method can isolate impulse-type vibrations of at least 2.8 dB, even with the adjusted mass arrangement.
      Citation: Applied Sciences
      PubDate: 2017-07-24
      DOI: 10.3390/app7070750
      Issue No: Vol. 7, No. 7 (2017)
       
  • Applied Sciences, Vol. 7, Pages 752: Automatic Definition of an Anatomic
           Field of View for Volumetric Cardiac Motion Estimation at High Temporal
           Resolution

    • Authors: Alejandra Ortega, João Pedrosa, Brecht Heyde, Ling Tong, Jan D’hooge
      First page: 752
      Abstract: Fast volumetric cardiac imaging requires reducing the number of transmit events within a single volume. One way of achieving this is by limiting the field of view (FOV) of the recording to the myocardium when investigating cardiac mechanics. Although fully automatic solutions towards myocardial segmentation exist, translating that information in a fast ultrasound scan sequence is not trivial. In particular, multi-line transmit (MLT) scan sequences were investigated given their proven capability to increase frame rate (FR) while preserving image quality. The aim of this study was therefore to develop a methodology to automatically identify the anatomically relevant conically shaped FOV, and to translate this to the best associated MLT sequence. This approach was tested on 27 datasets leading to a conical scan with a mean opening angle of 19.7° ± 8.5°, while the mean “thickness” of the cone was 19° ± 3.4°, resulting in a frame rate gain of about 2. Then, to subsequently scan this conical volume, several MLT setups were tested in silico. The method of choice was a 10MLT sequence as it resulted in the highest frame rate gain while maintaining an acceptable cross-talk level. When combining this MLT scan sequence with at least four parallel receive beams, a total frame rate gain with a factor of approximately 80 could be obtained. As such, anatomical scan sequences can increase frame rate significantly while maintaining information of the relevant structures for functional myocardial imaging.
      Citation: Applied Sciences
      PubDate: 2017-07-24
      DOI: 10.3390/app7070752
      Issue No: Vol. 7, No. 7 (2017)
       
 
 
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