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  Subjects -> SCIENCES: COMPREHENSIVE WORKS (Total: 428 journals)
Showing 1 - 200 of 265 Journals sorted alphabetically
AAS Open Research     Open Access   (Followers: 2)
ABC Journal of Advanced Research     Open Access  
Academic Voices : A Multidisciplinary Journal     Open Access   (Followers: 2)
Accountability in Research: Policies and Quality Assurance     Hybrid Journal   (Followers: 18)
Acta Materialia Transilvanica     Open Access  
Acta Nova     Open Access   (Followers: 1)
Acta Scientifica Malaysia     Open Access  
Acta Scientifica Naturalis     Open Access   (Followers: 3)
Adıyaman University Journal of Science     Open Access  
Advanced Science     Open Access   (Followers: 13)
Advanced Science, Engineering and Medicine     Partially Free   (Followers: 10)
Advanced Theory and Simulations     Hybrid Journal   (Followers: 4)
Advances in Research     Open Access   (Followers: 1)
Advances in Science and Technology     Full-text available via subscription   (Followers: 17)
African Journal of Science, Technology, Innovation and Development     Hybrid Journal   (Followers: 8)
Afrique Science : Revue Internationale des Sciences et Technologie     Open Access   (Followers: 2)
AFRREV STECH : An International Journal of Science and Technology     Open Access   (Followers: 4)
Akademik Platform Mühendislik ve Fen Bilimleri Dergisi     Open Access   (Followers: 2)
American Academic & Scholarly Research Journal     Open Access   (Followers: 6)
American Journal of Applied Sciences     Open Access   (Followers: 27)
American Journal of Humanities and Social Sciences     Open Access   (Followers: 15)
Anadol University Journal of Science and Technology B : Theoritical Sciences     Open Access  
Anadolu University Journal of Science and Technology A : Applied Sciences and Engineering     Open Access  
ANALES de la Universidad Central del Ecuador     Open Access   (Followers: 4)
Anales del Instituto de la Patagonia     Open Access  
Annali dell'Istituto e Museo di storia della scienza di Firenze     Hybrid Journal  
Applied Mathematics and Nonlinear Sciences     Open Access  
Apuntes de Ciencia & Sociedad     Open Access  
Arab Journal of Basic and Applied Sciences     Open Access  
Arabian Journal for Science and Engineering     Hybrid Journal   (Followers: 5)
Archives Internationales d'Histoire des Sciences     Partially Free   (Followers: 6)
Archives of Current Research International     Open Access   (Followers: 1)
ARO. The Scientific Journal of Koya University     Open Access  
ARPHA Conference Abstracts     Open Access   (Followers: 6)
ARPHA Proceedings     Open Access   (Followers: 4)
ArtefaCToS : Revista de estudios sobre la ciencia y la tecnología     Open Access   (Followers: 1)
Asia-Pacific Journal of Science and Technology     Open Access  
Asian Journal of Advanced Research and Reports     Open Access   (Followers: 2)
Asian Journal of Applied Science and Engineering     Open Access   (Followers: 2)
Asian Journal of Scientific Research     Open Access   (Followers: 3)
Asian Journal of Technology Innovation     Hybrid Journal   (Followers: 7)
Australian Field Ornithology     Full-text available via subscription   (Followers: 4)
Australian Journal of Social Issues     Hybrid Journal   (Followers: 7)
Avances en Ciencias e Ingeniería     Open Access  
Avrasya Terim Dergisi     Open Access  
AZimuth     Full-text available via subscription   (Followers: 2)
Bangladesh Journal of Scientific Research     Open Access   (Followers: 1)
Beni-Suef University Journal of Basic and Applied Sciences     Open Access   (Followers: 3)
Berichte Zur Wissenschaftsgeschichte     Hybrid Journal   (Followers: 10)
Berkeley Scientific Journal     Full-text available via subscription  
BIBECHANA     Open Access   (Followers: 2)
BibNum     Open Access  
Bilge International Journal of Science and Technology Research     Open Access   (Followers: 1)
Bioethics Research Notes     Full-text available via subscription   (Followers: 16)
Bistua : Revista de la Facultad de Ciencias Básicas     Open Access  
Bitlis Eren Üniversitesi Fen Bilimleri Dergisi     Open Access  
Bitlis Eren University Journal of Science and Technology     Open Access   (Followers: 1)
Black Sea Journal of Engineering and Science     Open Access  
Borneo Journal of Resource Science and Technology     Open Access  
Brazilian Journal of Science and Technology     Open Access   (Followers: 2)
Bulletin de la Société Royale des Sciences de Liège     Open Access  
Bulletin of the National Research Centre     Open Access  
Butlletí de la Institució Catalana d'Història Natural     Open Access  
Celal Bayar Üniversitesi Fen Bilimleri Dergisi     Open Access   (Followers: 1)
Central European Journal of Clinical Research     Open Access  
Chain Reaction     Full-text available via subscription  
Ciencia & Natura     Open Access   (Followers: 1)
Ciencia Amazónica (Iquitos)     Open Access   (Followers: 1)
Ciencia en Desarrollo     Open Access   (Followers: 1)
Ciencia en su PC     Open Access   (Followers: 1)
Ciencia Ergo Sum     Open Access  
Ciência ET Praxis     Open Access  
Ciencia y Tecnología     Open Access  
Ciencia, Docencia y Tecnología     Open Access  
Ciencias Holguin     Open Access   (Followers: 3)
CienciaUAT     Open Access   (Followers: 1)
Citizen Science : Theory and Practice     Open Access   (Followers: 1)
Communications Faculty of Sciences University of Ankara Series A2-A3 Physical Sciences and Engineering     Open Access  
Communications in Applied Sciences     Open Access  
Comprehensive Therapy     Hybrid Journal   (Followers: 3)
Comunicata Scientiae     Open Access   (Followers: 1)
ConCiencia     Open Access  
Conference Papers in Science     Open Access   (Followers: 2)
Configurations     Full-text available via subscription   (Followers: 9)
COSMOS     Hybrid Journal  
Crea Ciencia Revista Científica     Open Access   (Followers: 3)
Cuadernos de Investigación UNED     Open Access  
Cumhuriyet Science Journal     Open Access  
Current Issues in Criminal Justice     Hybrid Journal   (Followers: 15)
Current Research in Geoscience     Open Access   (Followers: 8)
Dalat University Journal of Science     Open Access  
Data     Open Access   (Followers: 4)
Data Curation Profiles Directory     Open Access   (Followers: 4)
Dhaka University Journal of Science     Open Access  
Dharmakarya     Open Access  
Diálogos Interdisciplinares     Open Access  
Digithum     Open Access   (Followers: 2)
Eastern Anatolian Journal of Science     Open Access  
Einstein (São Paulo)     Open Access  
Ekaia : EHUko Zientzia eta Teknologia aldizkaria     Open Access  
Elkawnie : Journal of Islamic Science and Technology     Open Access  
Emergent Scientist     Open Access  
Enhancing Learning in the Social Sciences     Open Access   (Followers: 9)
Enseñanza de las Ciencias : Revista de Investigación y Experiencias Didácticas     Open Access  
Entramado     Open Access  
Entre Ciencia e Ingeniería     Open Access   (Followers: 1)
Epiphany     Open Access   (Followers: 4)
Episteme Transversalis     Open Access  
Ergo     Open Access  
Estação Científica (UNIFAP)     Open Access   (Followers: 1)
Ethiopian Journal of Education and Sciences     Open Access   (Followers: 6)
Ethiopian Journal of Science and Technology     Open Access  
Ethiopian Journal of Sciences and Sustainable Development     Open Access   (Followers: 7)
European Online Journal of Natural and Social Sciences     Open Access   (Followers: 13)
European Scientific Journal     Open Access   (Followers: 9)
Evidência - Ciência e Biotecnologia - Interdisciplinar     Open Access  
Exchanges : the Warwick Research Journal     Open Access   (Followers: 2)
Extensionismo, Innovación y Transferencia Tecnológica     Open Access   (Followers: 6)
Facets     Open Access  
Fides et Ratio : Revista de Difusión Cultural y Científica     Open Access   (Followers: 1)
Fırat Üniversitesi Fen Bilimleri Dergisi     Open Access  
Fırat University Turkish Journal of Science & Technology     Open Access  
Fontanus     Open Access  
Forensic Science Policy & Management: An International Journal     Hybrid Journal   (Followers: 376)
Frontiers for Young Minds     Open Access  
Frontiers in Climate     Open Access   (Followers: 2)
Frontiers in Science     Open Access   (Followers: 1)
Futures & Foresight Science     Hybrid Journal   (Followers: 4)
Gaudium Sciendi     Open Access   (Followers: 1)
Gazi University Journal of Science     Open Access  
Gaziosmanpaşa Bilimsel Araştırma Dergisi     Open Access  
Ghana Studies     Full-text available via subscription   (Followers: 15)
Global Journal of Pure and Applied Sciences     Full-text available via subscription  
Global Journal of Science Frontier Research     Open Access   (Followers: 2)
Globe, The     Full-text available via subscription   (Followers: 4)
HardwareX     Open Access  
Heidelberger Jahrbücher Online     Open Access  
Heliyon     Open Access  
Himalayan Journal of Science and Technology     Open Access   (Followers: 1)
Hoosier Science Teacher     Open Access  
Iğdır Üniversitesi Fen Bilimleri Enstitüsü Dergisi / Journal of the Institute of Science and Technology     Open Access  
Impact     Open Access   (Followers: 2)
Indonesian Journal of Fundamental Sciences     Open Access  
Indonesian Journal of Science and Mathematics Education     Open Access   (Followers: 3)
Indonesian Journal of Science and Technology     Open Access  
Ingenieria y Ciencia     Open Access   (Followers: 1)
Innovare : Revista de ciencia y tecnología     Open Access  
Instruments     Open Access  
Integrated Research Advances     Open Access  
Interciencia     Open Access   (Followers: 1)
Interface Focus     Full-text available via subscription  
International Annals of Science     Open Access  
International Archives of Science and Technology     Open Access  
International Journal of Academic Research in Business, Arts & Science     Open Access   (Followers: 2)
International Journal of Advanced Multidisciplinary Research and Review     Open Access  
International Journal of Advancement in Education and Social Sciences     Open Access   (Followers: 1)
International Journal of Advances in Engineering, Science and Technology     Open Access   (Followers: 3)
International Journal of Applied Science     Open Access  
International Journal of Basic and Applied Sciences     Open Access   (Followers: 4)
International Journal of Computational and Experimental Science and Engineering (IJCESEN)     Open Access  
International Journal of Engineering, Science and Technology     Open Access  
International Journal of Engineering, Technology and Natural Sciences     Open Access  
International Journal of Innovation and Applied Studies     Open Access   (Followers: 12)
International Journal of Innovative Research and Scientific Studies     Open Access   (Followers: 5)
International Journal of Innovative Research in Social and Natural Sciences     Open Access   (Followers: 1)
International Journal of Network Science     Hybrid Journal   (Followers: 3)
International Journal of Recent Contributions from Engineering, Science & IT     Open Access   (Followers: 1)
International Journal of Research in Science     Open Access   (Followers: 2)
International Journal of Science & Emerging Technologies     Open Access   (Followers: 1)
International Journal of Sciences : Basic and Applied Research     Open Access  
International Journal of Social Sciences and Management     Open Access   (Followers: 2)
International Journal of Technology Policy and Law     Hybrid Journal   (Followers: 7)
International Letters of Social and Humanistic Sciences     Open Access   (Followers: 1)
International Review of Applied Sciences     Open Access  
International Scientific and Vocational Studies Journal     Open Access   (Followers: 1)
InterSciencePlace     Open Access   (Followers: 1)
Investiga : TEC     Open Access  
Investigación Joven     Open Access  
Investigación Valdizana     Open Access  
Investigacion y Ciencia     Open Access   (Followers: 1)
Iranian Journal of Science and Technology, Transactions A : Science     Hybrid Journal  
iScience     Open Access  
Issues in Science & Technology     Free   (Followers: 7)
İstanbul Ticaret Üniversitesi Fen Bilimleri Dergisi / İstanbul Commerce University Journal of Science     Open Access  
Istituto Lombardo - Accademia di Scienze e Lettere - Rendiconti di Scienze     Open Access  
Ithaca : Viaggio nella Scienza     Open Access  
J : Multidisciplinary Scientific Journal     Open Access  
Journal de la Recherche Scientifique de l'Universite de Lome     Full-text available via subscription   (Followers: 2)
Journal for New Generation Sciences     Open Access   (Followers: 4)
Journal of Chromatography & Separation Techniques     Open Access   (Followers: 12)
Journal of Advanced Research     Open Access   (Followers: 3)
Journal of Al-Qadisiyah for Pure Science     Open Access   (Followers: 1)
Journal of Analytical Science & Technology     Open Access   (Followers: 6)
Journal of Applied Science and Technology     Full-text available via subscription   (Followers: 1)
Journal of Applied Sciences and Environmental Management     Open Access   (Followers: 3)
Journal of Big History     Open Access   (Followers: 3)
Journal of Composites Science     Open Access   (Followers: 3)
Journal of Critical Thought and Praxis     Open Access   (Followers: 2)
Journal of Deliberative Mechanisms in Science     Open Access  
Journal of Diversity Management     Open Access   (Followers: 4)

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Anadolu University Journal of Science and Technology A : Applied Sciences and Engineering
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Print) 1302-3160 - ISSN (Online) 2146-0205
Published by Anadolu University Homepage  [6 journals]
  • A NUMERICAL MODEL ON GEOSYNTHETIC REINFORCED PILE SUPPORTED EMBANKMENTS

    • Authors: Mehmet İnanç ONUR; Eren balaban
      Abstract: Reinforced pile embankments arestarted use more commonly because they allow fast construction of highways. Whengeosynthetics are adopted to piled fills, this kind of structures are thencalled as geosynthetic reinforced piled structures. When the geosynthetics areused, area of pile caps is reduced because geosynthetic transfers fill load topiles by its membrane effect. In this study, effect of multi – layerreinforcement is investigated using 2D finite element method. For this purpose,settlements, pressures, excess pore water and horizontal displacements areanalyzed. Results showed that using two and three layers of reinforcement significantlydecreases settlements on foundation soil and embankment surface. Placement ofadditional layer has great effect on settlements, pressures, excess pore waterpressure and horizontal displacements. It is also found out that, two layers ofreinforcement is more effective when only settlements are considered.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • N-M AND M-K RELATIONSHIPS OF REINFORCED CONCRETE COLUMNS IN TEC2018

    • Authors: Ayten Günaydın; Hande Gökdemir
      Abstract: Reinforced concreteelements subject to moment, shear and axial force due to different level ofstatic and dynamic loads based on their location and material characteristics.These elements disseminate the loads based on their connections with otherelements. In particular, each column in the structure exhibits "combinedbending" behavior together with the resulting moment of the eccentricaxial force exerted. In the case of the axial load acting on one of thesymmetry axes (x or y axis) the uniaxial bending, and the axial load acting outof the symmetry axis, biaxial bending occurs. Also, since the structures arecomposed of two directional frames and slabs, the reinforced concrete columnsare subject to combined bending effects in both directions. Therefore, thedetermination of the ultimate strength and behavior of the reinforced concretecolumns depends on the interaction of axial force (N) and moment (M). In thisstudy, the N-M diagram of reinforced concrete columns is given considering thesection geometry, concrete and steel reinforcement strength and placement ofthe longitudinal reinforcements. The given N-M diagrams are prepared based onthe axial force limits in codes. In addition, the N-e diagram showing the axialforce and eccentricity relation of reinforced concrete column sections isgiven. Ductility ratios are given by plotting the moment curvature diagrams ofthe column sections at various axial force levels of the N-M diagram.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • Free Vibration and Buckling Analysis of Two Directional Functionally
           

    • Authors: Armağan Karamanlı
      Abstract: This study presents the freevibration and buckling behavior of two directional (2D) functionally gradedbeams (FGBs) under arbitrary boundary conditions (BCs) for the first time. Afour-known shear and normal deformation (Quasi-3D) theory where the axial andtransverse displacements are assumed to be cubic and parabolic variationthrough the beam depth is employed based on the framework of the Ritzformulation. The equations of motion are derived from Lagrange’s equations. Thedeveloped formulation is validated by solving a homogeneous beam problem andconsidering different aspect ratios and boundary conditions. The obtainednumerical results in terms of dimensionless fundamental frequencies anddimensionless first critical buckling loads are compared with the results fromprevious studies for convergence studies. The material properties of thestudied problems are assumed to vary along both longitudinal and thicknessdirections according to the power-law distribution. The axial, bending, shearand normal displacements are expressed in polynomial forms with the auxiliaryfunctions which are necessary to satisfy the boundary conditions. The effectsof shear deformation, thickness stretching, material distribution, aspectratios and boundary conditions on the free vibration frequencies and criticalbuckling loads of the 2D-FGBs are investigated.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • Characterizations and Catalytic Activities Investigation of Synthesized
           Solid-Based Heterogeneous Catalysts in the Esterification Reaction

    • Authors: Veli Şimşek; Kırali MÜRTEZAOĞLU
      Abstract: Mesoporous materials functionalized with STA(Silicotungstic acid) havebeen proved to be efficient catalysts for esterification reactions. In theinvestigation, impregnation method was applied for the synthesis of STA/MCM-41catalysts. MCM-41 and STA(Silicotungstic acid) were used to silica source andactive material respectively. The active material was loaded bydry-impregnation method after silica source. Molar ratios of catalysts weredetermined by 1.25, 2.5 and 5% (W/Si). Actually, this molar ratio values arevery low for the impregnation method. But catalysts were successfullysynthesized by applying impregnation method. And catalytic activities ofSTA/MCM-41 catalysts were investigated with an ethyl acetate reaction. On theother hand, the second reaction of STA/MCM-41(2.5%) catalyst was carried out inthe presence of under identical conditions after the first reaction. Before andafter reactions, the physical properties of the catalysts were determined byXRD, DRIFT, BET, SEM and Mapping analysis methods. 
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • MAGNETIC MESOPOROUS SILICA NANOCOMPOSITES PREPARED WITH DIFFERENT SIZED
           Fe3O4: STRUCTURAL AND MAGNETIC PROPERTIES, CATALYTIC EFFECTS

    • Authors: Sezer Erdem; Beyhan Erdem, Ramis Mustafa Öksüzoğlu
      Abstract: The magnetically separable mesoporous silicananocomposites were successfully prepared through a one-pot method including theco-condensation of tetraethoxysilane (TEOS) as silica precursor and3-mercaptopropyl trimethoxysilane (MPTMS) as functionalizing agent accompaniedwith hydrogen peroxide for oxidation of mercapto groups and triblock copolymersas structure directing agent in the presence of ferromagnetic andsuperparamagnetic Fe3O4 nanoparticles. By incorporatingthe superparamagnetic (near zero coercivity) Fe3O4nanoparticles to the mesoporous silica (SBA-15) and functionalizing withsulfonic acid groups instead of ferromagnetic Fe3O4 nanoparticles,we developed versatile nanocomposite having superior properties with respect tomagnetism, catalysis and porosity. Reducing the particle size of Fe3O4from the ferromagnetic regime to the superparamagnetic regime, the pore closurecould be eliminated because of the more open pore as well as saving magneticproperties.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • HETEROGENEOUS CATALYSIS IN SUSTAINABLE GREEN SOLVENT: ALKENES
           HYDROGENATION WITH NEW SILICA IMMOBILIZED PALLADIUM COMPLEX CONTAINING
           S,O-CHELATING LIGAND

    • Authors: Filiz YILMAZ
      Abstract: Pd(II) complex containing S,O-chelating ligandwas immobilized on surface of the amine functionalized silica support in scCO2media. Silica-based catalyst (SiO2-ThiophPd(II)) were characterized byIR, SEM, XRF, and BET analyses. The catalytic activity of the immobilizedcatalyst in hydrogenation reactions of alkenes has been compared with thehomogeneous counterpart. SiO2-ThiophPd(II) catalyst showed goodactivity and reusability than homogeneous system. The best conversion in styrene hydrogenation wasobtained with TOF value as 5871 h-1 at 370 K, 10 bar H2and 1500 psi total pressure. Especially, whilehomogeneous counterpart has not activity in cyclohexene hydrogenation, it hasbeen provided 100% cyclohexane conversion with the immobilized catalyst. It has also been foundthat the catalyst can be reused at least ten times without significant loss ofactivity in the styrene hydrogenation
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • PARAMETERS AFFECTING LYCOPENE EXTRACTION FROM TOMATO POWDER AND ITS
           ANTIOXIDANT ACTIVITY

    • Authors: Mehmet ÜSTÜNDAŞ; H. Banu YENER, Şerife Ş. HELVACI
      Abstract: The extraction of lycopene from dried tomatopowder was carried out using ultrasound assisted (UAE) and conventional solvent(COSE) extraction methods with varying liquid/solid ratio (10:1-50:1),extraction time (5-60 min), temperature (20-50°C) and ultrasonicpower (150-200 W). The response surface methodology was used to optimize theextraction parameters and to determine their individual and interaction effectson the extraction yield. The maximum extraction yields of UAE (722.321 mg lycopene/kgtomato powder) and COSE (975.833 mg lycopene/kg tomato powder) was observedusing the following conditions: 166 W for 26 min, and a 56:1 liquid/solidratio, and 45°C for 50 min, and a 56:1 liquid/ solid ratio,respectively. At the same extraction conditions UAE is reaching the sameextraction yield faster than the COSE. Even the lycopene contents of theextracts were the same, the antioxidant capacity of the UAE and COSE extractswere 12.48 and 11.08 mg Trolox/g tomato powder, respectively.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • COPRIME ARRAYS WITH ENHANCED DEGREES OF FREEDOM

    • Authors: Ahmet M. Elbir
      Abstract: Coprime array geometriesprovide robust performance for direction-of-arrival estimation problem withmore sources than sensor elements. In previous works it is shown that K sourcedirections can be resolved using only 2M + N -1 sensor elements where K is lessthan or equal to MN. In this paper we introduce a new approach to enhance thedegrees of freedom (DOF) from MN to 2MN by using the same number of sensorelements. The proposed method is based on computing the covariance matrix ofthe observation data multiple times. Hence more DOF can be obtained. Theresulting cross terms corresponding to the coherent sources are modeled as aninterference in a sparse recovery algorithm which is solved effectively by an alternatingminimization procedure. The theoretical analysis of the proposed method isprovided and its superior performance is evaluated through numericalsimulations.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • PLASMA MODIFIED WO3 HYBRIDS WITH ALTERED DONOR GROUPS FOR FLEXIBLE
           ELECTROCHROMIC APPLICATIONS

    • Authors: Esin Eren; Ceyda Alver, aysegul uygun oksuz
      Abstract: Thisstudy reports the preparation of hybrids of tungsten trioxide/polythiophene (WO3/PTh)and tungsten trioxide/polyfuran  (WO3/PFu)using a rotating capacitively coupled radio frequency (rf) plasma process. Theprepared hybrid characteristics were measured using scanning electron microscopy-energy dispersive X-rayspectroscopy (SEM-EDS) and X-ray diffraction analysis (XRD). WO3, WO3/PTh,WO3/PFu thin films were deposited onto flexible substrates using electronbeam evaporation technique for high electrochromic performance purposes. Theeffect of thiophene and furan moieties on the optical and electrochromic properties of the flexible hybrid-based ECDs was investigated using optical and electrochemical measurements. Especially, the WO3/PTh-based ECD shows markedimprovements of cathodic electrochromism over WO3-based ECD: theoptical contrast of 33% at 750 nm, the switchingtimes (bleaching time: 1.63 s, coloration time: 0.41 s),  the coloration efficiency of 502 cm2/C.  
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • ATMOSPHERIC CONCENTRATIONS OF INORGANIC POLLUTANTS (NO2, SO2 AND OZONE) IN
           ESKİŞEHİR: SPATIAL AND VERTICAL VARIATIONS, WEEKDAY-WEEKEND DIFFERENCES
           

    • Authors: Özlem Özden Üzmez
      Abstract: Atmosphericconcentrations of inorganic pollutants (NO2, SO2 andozone) were measured at three different sampling sites in Eskişehir. Sampleswere collected between 25th of March and 8th of April2016 by using passive sampling method. During two-week sampling study, each week was divided to three sub-periodsto investigate weekday and weekend differences of the pollutant concentrations.One-time vehicle counts during morning,noon and evening hours for both weekday and weekend periods were inspected. Thehighest NO2 concentrations were measured at the sampling site havingurban, traffic and residential characteristics. Positive relationship betweenNO2 concentrations and traffic density was observed. Reverse trendwas determined for ozone. Ozone concentrations were higher at the sampling sitefar from the city center. Spatial variations of SO2 concentrationswere similar to those of NO2. Weekday NO2 concentrationswere higher than weekend concentrations while higher ozone concentrations wereobserved in weekend. Weekend and weekday SO2 concentrationswere quite similar at all sampling sites. Beside spatial variations, verticalvariations of each pollutant were also investigated. NO2concentrations decreased with the elevation and reverse case was observed for ozone with increasing concentrations at the same elevation range. SO2 concentrations increased withthe elevation due to chimney gas emissions.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • DEPENDENCE OF SiAlON-TiN COMPOSITE PROPERTIES ON TiN REINFORCEMENT
           PARTICLE SIZES

    • Authors: Nurcan Çalış Açıkbaş; Gökhan Açıkbaş
      Abstract: TiN particle size is an effective parameter onmicrostructure, mechanical and physical properties of SiAlON-TiN composites. Inthis study, the effect of TiN particle size (nano and micron level) onmicrostructural evolution, mechanical and physical properties wereinvestigated. The phase and microstructural evolution, SEM and the XRDcharacterization methods were used to observe the effects of TiN particle size.Indentation fracture toughness and Vickers hardness of the samples weremeasured in order to evaluate the mechanical behavior. Archimedes principle wasused in order to determine bulk density and porosity. Correlation between TiNparticle size and hardness, fracture toughness, microstructure, phase evolutionwas discussed. It was observed that decrease in particle size led to little improvementin fracture toughness and hardness.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • APPLICATION OF MULTI-CRITERIA DECISION MAKING FOR GEOLOGICAL CARBON
           DIOXIDE STORAGE IN TURKEY¬

    • Authors: Irem Firtina Ertis
      Abstract: In contemporary era, carbon sequestration has becomean important issue. Rapidly increasing population, higher life-standards andtechnological advancements consistently increase the amount of emissions,especially CO2. Nowadays,the most promising solution is to minimize the carbon dioxide emissions withusing carbon capture and storage (CCS) technologies for a better future. The problem is to choose the best location for CO2storage which is a crucial and challenging multicriteria decision problem. The objective of this paper is to determine themost appropriate city for carbon dioxide storage in Turkey, by demonstrating asuccessful implementation of Multi-criteria Decision Making (MCDM) tool. This study presents the use of MCDM method based on Technique for Order Preference by Similarity to IdealSolution (TOPSIS) toassess the suitable location for CO2 storage. For that purpose, 4 alternative locations were evaluated via 8criteria which are determined according to the opinions of the experts withbackground information from the field. Towards this end, MCDM method, namely, TOPSIS,was utilized for the location evaluation. Consequently, this method detects Diyarbakır as CO2 storagearea which is also one of the most important city of Turkey for having finishedoil reservoirs and for its geopolitical location.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • Investigation of Thermomechanical Behaviors of Aged Ti55.68Ni44.32 Alloys

    • Authors: iskender özkul; canan aksu canbay
      Abstract: TiNi alloys are used in places where requiring precision jobs for the last few decades. Thermally induced shape memory alloys such as TiNi, exposures in use and the temperature causes the aging effects on alloy. In our experimental study, we have aimed to investigate of aging effects depends on time and temperatures for TiNi alloys. Three different temperature values and seven waiting periods applied and totally 22 experiments were conducted and the results were examined. Time depended results, especially for 200 °C samples exhibited more stable state than 300 and 400 °C. When the temperature values are considered, remarkably increase is observed after 200 °C.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • Evaluation of Anaerobically Digested Biomass in Catalytic Supercritical
           Water Gasification for Biofuel Production

    • Authors: Tülay Güngören Madenoğlu
      Abstract: Digested water hyacinth with activated sludge asinoculum were obtained after anaerobic digestion at 35 and 45°C.High organic content of digested biomass were evaluated through gasification atsupercritical conditions of water in the absence and presence of catalysts(KOH, NaOH, LiOH and K2CO3)with 10 wt.% of volatile solid in feed.Supercritical water gasification of digested biomass was performed in batchreactor system at temperature and pressure ranges of 500–600°Cand 350–450bar, respectively. The highestcarbon gasification efficiency, hydrogen and methane yields were reached at 600°C(with samples digestedat 45°C) in the absence of catalyst as 84.6 (g C in gaseous/g C in digestate), 53.0 (mol H2%) and 12.5 (mol CH4%),respectively. High organic content of digested biomass was converted bysupercritical water gasification to hydrogen and methane rich gas, and aqueousproducts (aliphatic hydrocarbons, phenol, substitutedphenols, N-heterocyclic, substituted N-heterocyclics, and substituted benzene) that can be evaluated as platform chemicals.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • PERSONNEL SELECTION FOR PROMOTION USING AN INTEGRATED FUZZY ANALYTIC
           

    • Authors: Yavuz Özdemir; Kemal Gökhan Nalbant, Hüseyin Başlıgil
      Abstract: The basic idea of personnel selection is tochoose the best candidate for a job. Personnel selection is crucial in humanresources management and also a very important issue for both academicians andindustrialists. Personnel selection can be handled as a Multi Criteria DecisionMaking (MCDM) problem. The aim of this paper is to determine the bestpersonnel using the integrated Fuzzy Analytic Hierarchy Process (FAHP) and GreyRelational Analysis (GRA) methodology. FAHP is used to determine the importanceweights of personnel (17 alternatives) according to personnel selectioncriteria (22 subcriteria are categorized under 5 main criteria).  Then, obtained fuzzy importance weightsdefuzzified by centroid method. After that, defuzzified importance weights of personnelaccording to personnel selection criteria are integrated with a GRA model toprioritize the personnel alternatives. For a case study in Turkey, the rankingof the alternatives is calculated using the integrated FAHP-GRA model, and thebest-performing personnel is selected for promotion. According to thismethodology, managers/human resources department can easily predict how theycan evaluate and promote employees.The proposed methodology provides less data and cananalyze many factors that can overcome the disadvantages of statistics methodsin the literature. The main contribution of this study is to reduce data for apreference matrix using the integrated methodology. As a result, the number oftransactions decrease. To the authors’ knowledge, this will be the first studywhich integrates Fuzzy Analytic Hierarchy Process (FAHP) and Grey RelationalAnalysis (GRA) methodologies for human resources in the area of industrialengineering.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • INVESTIGATION OF HYDROPOWER GENERATION FROM IRRIGATION DAMS

    • Authors: Recep Bakış; Yıldırım Bayazıt, Cengiz Koç, Dost Mohammad Ahmady
      Abstract: Evaluation of renewable energyresource is very important for Turkey. As geodetic and fossil energy thatTurkey owns is insufficient and do not meet the demand. For this reason, tendingtowards hydro-electric power is an applicable option and is one of the mostimportant energy resource for the country. From water resources point of view,water potential of large and small streams, for the purpose of energyproduction is vital for the country. Thereby, the existing deficit gap relevantto the energy, is reduceable. Withinthis paper, Seydisuyu basin has been selected as the research area.Precipitation in the basin is drained by Seydisuyu stream. Only two dams namedas Kunduzlar and Çatören, were constructed and are currently in operation inthe basin. These dams were built for the purposes of only irrigation and floodcontrol, in the basin. Water potential of the basin is very small, due to theslight amount of precipitation within that area. Accordingly, planning of onlysmall-scale hydro-electric energy potential is considerable over these dams, forregion/national economic advantage of the country. In this study, the hydro-electricpower potential of these two existing dams, were investigated. For thispurpose, using 19 years of monthly data discharging from six existing flowgauging stations in the basin, the amount of hydroelectric energy generation ofthese dams was analyzed individually. As the result of these analysis, thecalculation of the annual energy production capacity, the installed powerproduction, and the annual economic contribution for both Çatören and Kunduzlar dams wereestimated as 4.14 GWh (2.15 GWh (Çatören) + 1.99 GWh (Kunduzlar)),0.843 MW (0.273 MW (Çatören) + 0.57 MW (Kunduzlar)), and 495000 USD (257000USD (Çatören) + 238000 USD (Kunduzlar)), respectively.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • Urban Light Rail Transportation Systems Catenary Line Anti-Icing
           Applications, Laboratory and Field Tests

    • Authors: Ümit Er; Fatih Hayati ÇAKIR
      Abstract: Problems such as freezing, icing, and/ or snow accumulation in the machine systems during the winter can adverselyaffect the performance of the systems, sometimes stopping them altogether. Oneof the systems affected by winter conditions is the energy transmission lines.If not intervened, snow and / or ice accumulating on electrical wires can causeelectrical transmission performance to drop, and extreme cases can cause wirebreaks due to heavy wires. One of the energy transmission systems where power linesare open to the atmosphere is the pantograph-catenary systems that take upelectrical energy. Frosting and ice accumulation on the catenary lines leads toarc formation and, in some cases, can interfere with electrical conductionbetween the pantograph and the catenary line. In the case of light railtransportation systems, this problem could lead to problems at higher ratesthan other rail systems. In Turkey, the activities to be done for preparationof winter and route maintenance in the intercity railway transmission lines arewell known, but procedures for light rail systems are being newly prepared. Inparticular, the use of light rail systems in winter, where the conditions aremore difficult, brings with it some problems. It is inevitable to anticipatethe problems that may arise and to work to solve these problems. In this study,an experimental setup was designed to simulate the snow, dew formation on thecopper wires in order to prevent / eliminate the icing problem that occurs inthe urban light rail transportation systems catenary lines. Field tests werealso carried out by applying anti-icing chemical solution in the catenary linesof the Eskişehir urban light rail transport system (ESTRAM). As a result of thefield tests, it has been seen that the mono ethylene glycol application towires can reduce arc formation and wear of the lines considerably. It has evenbeen found that the application mono ethylene glycol before freezing of theline has the potential to reduce wear, breakdown and maintenance costs in thecatenary lines.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • Residents’ Perceptions of Riverine Landscape Changes; Case Study of
           Beykoz Stream/ Istanbul

    • Authors: Sahar Pouya; Fatma Ayçim TÜRER BAŞKAYA
      Abstract: Residents are an inevitable part of any urbanplan and knowing about their perceptions is a key factor to change the urbanareas. This issue is of greater importance in urban river enhancement projects,as the rivers are associated with various economic, cultural, and social issuesof the residents. The main goal of the present research is to assess riverinelandscape of Beykoz in Istanbul after bearing tremendous changes. The riverinelandscape is surveyed considering the natural features, physical elements, andthe people’s perception in particular. The main part is based on interview withthe local residents to achieve their comments about the stream changes and theecological and cultural memory related the stream. The results indicated thatthere is valuable information in perception of the residents about naturalcorridors like the streams that should be evaluated before any restorative operation.Changing the stream channel and its bank with no care of the residents’dimension will disturb the place identity, valuable belongingness, and theunique meanings associated with the rivers. Visual access to the stream, thestream’s natural landscape with native vegetation, its biodiversity, its soundand color are the factors that should be maintained during the urbandevelopment projects.
      PubDate: Sat, 30 Jun 2018 00:00:00 +030
       
  • EFFICIENCY ESTIMATION OF INDUCTION MOTORS AT DIFFERENT SIZES WITH
           ARTIFICIAL NEURAL NETWORKS AND LINEAR ESTIMATION USING CATALOG VALUES

    • Authors: Mi̇ne Sertsöz; Mehmet Fidan, Mehmet Kurban
      Abstract: Induction motors are the mostpreferable motors for the locomotives because of their simple but robuststructure. The efficiency of the preferred motor is crucial for the limitationof the load pulled by the locomotive and suitability for the geographicconditions. Forthis reason, determining energy efficiency and operating conditions ininduction motors is a very important issue. It is often not possible toexperimentally realize the efficiency of induction motors, because this meansthat the motor is stopped during that time. This is an obstacle to theefficiency of the operator while trying to contribute to energy efficiency inthe enterprise.  Therefore,estimation the efficiency of the motor provides a significant contribution tothe operation and energy efficiency. Many studies have been made in the literature,which related to this issue. The difference of this study is that efficencyestimations of induction motors at 17 different power are realized withartificial neural networks and linear prediction by looking at the values ofspeed, current and moment in the catalog. And also before the estimation is applied, thestatistical relations between efficiency and moment, efficiency and speed,efficiency and current of the motor are also analyzed and presented.
      PubDate: Sat, 31 Mar 2018 00:00:00 +030
       
  • STATISTICAL ASSESSMENT OF CAREERS OF DOCTORATE HOLDERS SURVEY BY
           CORRESPONDENCE ANALYSIS: THE CASE OF TURKEY

    • Authors: Zerrin AŞAN GREENACRE
      Abstract: Nowadays,doctorate holders are not only academician and researcher, also they play rolesacross a wide range of working areas within society. These areas are increasingmultiway.The aim of this study is to givestatistical evaluation careers of doctorate holders survey using  the correspondence analysis with supplementaryvariables. In this paper  we focused on careers ofdoctorate holders  in Turkey. It washeld a survey by  Turkish   Statistical Institute on this subject. Thissurvey consists many questions like gender, age, employment situation, a field  of science, etc. Using correspondenceanalysis we investigated doctorate holders according to their gender andemployment situation and employment sector. It was showed how the employmentsituation of doctorate holders changes according to gender and year ofdoctorate award and doctorate holders’ satisfaction level on their principaljob by selected title.
      PubDate: Sat, 31 Mar 2018 00:00:00 +030
       
  • Dynamic k Neighbor Selection for Collaborative Filtering

    • Authors: Halil Zeybek; Cihan KALELİ
      Abstract: Collaborative filtering is a commonlyused method to reduce information overload. It iswidely used in recommendation systems due to its simplicity. Intraditional collaborative filtering,recommendations are produced based on similarities among users/items. In this approach, the most correlated k neighbors are determined, and a prediction iscomputed for each user/item by utilizing this neighborhood. Duringrecommendation process, a predefined kvalue as a number of neighbors is used for prediction processes.  In this paper, we analyze the effect ofselecting different k values for each user or item. For this purpose, we generate amodel that determines k values foreach user or item at the off-line time. Empirical outcomes show that using thedynamic k values during the k-nnalgorithm leads to more favorable recommendations compared to a constant k value.
      PubDate: Sat, 31 Mar 2018 00:00:00 +030
       
  • INVESTIGATION OF STRONG COLUMN – WEAK BEAM RATIO IN MULTI-STOREY
           STRUCTURES

    • Authors: HANDE GÖKDEMİR; AYTEN GÜNAYDIN
      Abstract: Itis expected that the engineering constructions should carry the vertical andhorizontal loads during the service within the determined safety margin. Basicprincipal of having strong column weak beam preference is essential forearthquake resistant structures for all construction types including concrete,steel, wood and prefabricated. The major criteria for having earthquakeresistant structure is to ensure that the columns are stronger and carry themost load than the beam in the nodes. This criterion has been widely adopted inearthquake codes in Europe, USA,Japan and India. It is possible to absorb andconsume the earthquake energy via beam plastic joint hinges if the columns areconstructed to be more durable than the beams. For this, it is foreseen thatthe ratio of the ultimate strength of the upper and lower columns to the rightand left beams (β) should be greater than one (β = 1.2) in the beam-columnjoints as stated in the Turkish Earthquake Code. This coefficient is usuallygreater than 1.2 in the earthquake codesadopted in the world. It was observed that many structures were damaged orcollapsed due to not meeting the coefficient criteria stated above. Thiscriterion is the most effective one among many to prevent the damage in thestructure under seismic action. In this study, the effect of the change in thecoefficient on the column and beam moments is investigated under the TurkishEarthquake Code. Different numerical examples are presents for the coefficientof 10. The results of the investigation highlighted that irregularity in thestrong column weak beam composition may negatively affect the otherirregularities in the structure.
      PubDate: Sat, 31 Mar 2018 00:00:00 +030
       
  • EXPERIMENTAL AND ANALYTICAL INVESTIGATION ON STATOR WINDING TURN INFLUENCE
           IN SQUIRREL CAGE INDUCTION MOTOR PERFORMANCE: ENERGY EFFICIENCY

    • Authors: Asım Gökhan Yetgin; Murat İmre
      Abstract: In the designing steps of theinduction machines, reducing the power consumption level of the inductionmachine is a very important issue. Winding topology is one of the mostimportant design parameters for induction machines. Variation of the number ofturns in the slots has a significant effect on the performance of the machine.In this study, unlike the studies in the literature, only the number of turnsare changed (all other motor parameters are constant) and analyses areperformed. 6 different induction machines which have 6 different windingtopologies are designed. 3 of the machines are designed half coiled and theother 3 machine are designed whole coiled. Both winding topologies havedifferent turn numbers for a single slot. The turn numbers are 96, 106 and 116respectively. No-load, locked rotor, and load tests are conducted on thesemachines. According to the test results and analytical results, performances ofthe machines are considered. In this way, increasing the turn number for bothwinding topologies has a decreasing effect on the iron losses of the motor.Similarly, increasing of the stator and rotor resistances directly affects thecopper losses of the machine negatively. When considering the efficiencies ofthe machines, maximum efficiency is achieved for half coiled 116 turns numberedtopology. Similarly, maximum efficiency is achieved for whole coiled 106 turnsnumbered topology.
      PubDate: Sat, 31 Mar 2018 00:00:00 +030
       
  • A NUMERICAL SOLUTION OF THE ADVECTION-DIFFUSION EQUATION BY USING EXTENDED
           CUBIC B-SPLINE FUNCTIONS

    • Authors: Melis Zorsahin Gorgulu; Idris Dag, Sumeyye Dogan, Dursun Irk
      Abstract: In this paper, numerical solution of theadvection-diffusion equation is obtained by using extended cubic B-splinefunctions. For space discretization, the extended cubic B-spline Galerkinmethod is used to integrate the advection-diffusion equation and for timediscretization, the Crank-Nicolson method is employed to obtain the fullyintegrated advection-diffusion equation. The maximum error norm has been usedto show the accuracy of the method. Robustness of the suggested method is shownby studying some classical test problems and comparing the results with someearlier ones.
      PubDate: Sat, 31 Mar 2018 00:00:00 +030
       
  • THE RELATIONSHIP BETWEEN FLIGHT OPERATIONS AND ORGANIZATIONS IN AIRCRAFT
           ACCIDENTS; THE APPLICATION OF THE HUMAN FACTOR ANALYSIS AND CLASSIFICATION
           SYSTEM

    • Authors: Kadir Dönmez; Suat Uslu
      Abstract: Aviation history is replete with lessons learned fromaccidents. Aircraft accidents have greatly contributed to the formation ofaviation laws. Analysis conducted after accidents are the first steps taken forthe prevention of further accidents.Accidentanalyses are carried out by the countries' accident investigation board wherethe accident happened or the one where the airline is registered. Several models are used in the analysis of accidents. One of these models, The Human Factors Analysis andClassification System was put forward by Shappell and Wiegmann after examining morethan 2,000 accidents. This system is based on Reason's Swiss Cheese Model and,therefore, also the Domino Theory. According to The Human Factors Analysis andClassification System, the cause of accidents consists of 4 levels of factorsthat affect each other. These are: organizational influences, unsafemanagement, preconditions for unsafe acts and unsafe acts. Although an accidentmay seem to be caused by unsafe acts, behind the accident there are many causesextend from the managers to organizations. In this study, the databases of differentcountries' accident investigation boards were studied and the official accidentreports of "planned and commercial" passenger flights were examined.These reports were analyzed and coded according to the Human Factors Analysisand Classification System. As aresult, the size and scope of the relationships between organizationalinfluences and unsafe acts that led to the accidents were revealed. 
      PubDate: Sat, 31 Mar 2018 00:00:00 +030
       
 
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