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Gazi University Journal of Science
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Online) 2147-1762
Published by Gazi √úniversitesi Homepage  [9 journals]
  • Effect of Wall Colors and Usage Rates on The Perception of Interior Spaces

    • Authors: Kübra AKSOY ÖZLER; M. Lütfi HİDAYETOĞLU, Kemal YILDIRIM
      Abstract: In this study, it was aimed to determine the effects of colors and the usage rates in interior spaces on the spatial perceptions of users. With this objective, a living space was designed in a manner that would have three different colors (warm, neutral, and cool) and usage rates at 10%, 50%, and 100% and digital visuals were prepared. A total of 233 subjects participated in the research questionnaire and the data obtained were analyzed. In conclusion, it was determined that the living spaces which were colored at a low rate were perceived more positively according to the Semantic Differentiation Scales compared to the completely colored spaces. The spaces where warm and cool colors were used at the rate of 10% were perceived as more spacious and beautiful compared to the spaces where colors were used at the rates of 50% and 100%, whereas it was observed that when the values received were from positive to negative, they were listed in the form of 10% > 50% > 100%. Despite this, it was determined that the spaces where warm colors were used at the rates of 50% and 100% were perceived as more informal. Furthermore, it was observed that the differences in the colors used on the walls and the usage rates were changing according to gender and professions. Accordingly, it was determined that especially females and interior architects preferred, even more, the spaces with warm colors having a low usage rate.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Prioritizing Individuals Who Will Have Covid-19 Vaccine with
           Multi-Criteria Decision Making Methods

    • Authors: Emre YAZICI; Sabire İrem ÜNER, Aslı DEMİR, Sevda DİNLER, Hacı Mehmet ALAKAŞ
      Abstract: This study aims to prioritize individuals in vaccination for the effective use of the COVID-19 vaccine, which has limited supply and does not seem possible to be supplied by all countries at the same time. In the study, multi-criteria decision-making methods (MCDM), which offer practical solutions to decision problems, were used considering the structure of the problem. First, the analytic hierarchy process (AHP) method was used to calculate the weights of the criteria. Then, the ranking of the priorities of the individuals was carried out with the PROMETHEE method. Here, the AHP and PROMETHEE methods are used in an integrated manner. It has been determined that the highest priority individual in vaccination is a healthcare worker with a high potential for transmission. In order of priority, the second individual was identified as workers. In this study, a hierarchical structure was created to prioritize individuals who will be vaccinated against COVID-19 and the problem was solved in two stages. A health policy proposal was made to health managers to use limited vaccine resources by prioritizing individuals effectively. In terms of efficient and effective use of resources during possible pandemic periods, the application process of the study provides an exemplary solution for decision-makers and contributes to the solution of similar decision problems encountered both in the literature and in real life. At the same time, offers solution for disasters that require effective use of limited resources, etc. The implementation process of the study may also be taken into account in exceptional circumstances.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • The Comparison of Classical and Bayesian Structural Equation Models

    • Authors: Gizem ERKAN; Murat DOĞAN, Hüseyin TATLIDİL
      Abstract: This study aims to compare classical Structural Equation Modeling (SEM) and Bayesian Structural Equation Modeling (BSEM) in terms of ordered categorical data. In order to show the relationship between service dimensions and banks’ customers’ satisfactions, a data were analyzed with classical SEM and BSEM parameter estimation methods. In the Banking Service Quality Scale (SERVQUAL), which consists of sequential categorical data, classical SEM and BSEM were compared to evaluate customer satisfaction. In classical SEM, parameter estimations were made according to the Maximum Likelihood (ML) estimation method. In most of the studies using SERVQUAL in the literature, the results found in previous studies could not be used as prior informative because the service dimensions consisted of different number of factors. For this reason, considering that the results could yield similar results with the ML estimation method due to the high sample size, the use of conjugate prior was preferred instead of the non-informative prior due to the ordinal categorical nature of the data in the BSEM analysis. Since the questionnaire used in the study had a Likert type scale structure, the threshold values were calculated for ordered categorical data and used as prior informative. Thus, by using the threshold values obtained from the data set, a faster convergence of the parameters was achieved. As a result, service dimensions affecting satisfaction according to the ML parameter estimation method were found, Assurance, Physical Appearance, and Accessibility. In addition to these, Reliability as a service dimension was found to be also statistically significant in BSEM.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • A Simple Selection Method of PV Systems for University Campuses

    • Authors: Marıam BARA; Gülsu ULUKAVAK HARPUTLUGİL
      Abstract: This paper briefly outlines part of the research work being carried out on the application of the photovoltaic systems to cover universities’ electrical energy needs, with due consideration to the technical, architectural, economic, social. and legal aspects and impacts of this application. The paper considers optimizing the PV system selection objectives and methodology with a case study application. at a university campus in Ankara, Turkey. The main objective here is to develop a practical simple method of selecting an optimum PV system that gives the maximum energy yield possible in a certain period of one year, with the minimum specific energy cost per kWh, where a multiple-variable multi-criteria decision-making making method is applied, to help designers and system engineers in selecting the optimum system. The developed method is demonstrated in the example of the typical case, where the recommended PV system was turned out to be at an Azmuth angle of 0 degrees, the PV technology was monocrystelline Silicon, the annual electrical energy yield per 100 m2 of PV modules surface area 22.4 MWH/Year, the specific electrical energy cost was 0.15 Euos/Kwh, as a first merit option, making a difference of around 13% of saving compared with the 10th last option. The work concludes that a viable PV application is feasible, encouraging its application in various campuses provided that comprehensive planning and careful considerations are given to the related aspects.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Traffic Flow Pattern Based Approach to Predict Real Driving Emission Test

    • Authors: Muhammet AYDIN; Cem SORUŞBAY, Hikmet ARSLAN
      Abstract: Due to the poor representation of NEDC emission test, the European Commission put into the force a new procedure, which contains both a laboratory test and a real word driving test. In this new test procedure, even though WLTC replaces NEDC, it is required to test the vehicle under real traffic conditions, which contains urban, rural and highway segments. Due to the new emission regulation, considerable number of academic work focus on the creation of RDE (Real Driving Emission) routes and RDE tests. In this study, it is introduced a new methodology for creating potential RDE routes. The routes, created in MATLAB code by using Istanbul road data containing a half an hour average trip records were used to predict a probable RDE test road. This model creates a number of RDE routes starting from defined coordinates and then analyses all alternative routes with respect to traffic flow rate and RDE boundary conditions identified by the European Commission. The routes obtained using the methodology developed are tested in real life conditions and evaluated according to actual existing traffic conditions. The agreement between the results of the method and the results of the actual driving test is limited in urban road section. However, for rural and highway road sections, there is a significant agreement between the predictions and actual test results.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • The Study of Interaction Activity of Nickel (ll) Phthalocyanine Complex
           Bearing Tetra Substituted Phenoxy-3-Methoxybenzoic Acid Groups with DNA

    • Authors: Ali ARSLANTAS; Mehmet Salih AĞIRTAŞ
      Abstract: Nickel phthalocyanine complex containing 3-methoxybenzoic acid groups was acquired and specified by way of Fourier Transform Infrared, NMR and UV-Visble spectroscopy procedures. Interaction of PcNi with the DNA molecule was examined via electronic absorption spectra, fluorescence spectra, melting point, viscosity, and the electrophoresis technics, respectively. The interaction activity of PcNi against the DNA was examined by way of absorption spectra titrations and the fluorescence spectra, farther by conducting melting point, viscosity procedures in the buffer of a pH 7.02. The obtained outcomes from these methods demonstrated that PcNi indicated substantial binding affinity to the DNA via intercalating by Kb of 1.31 x 106 m-1. Further, the interacting activity of PcNi on the DNA was analyzed by which electrophoresis technique and this procedure indicated that PcNi complex exhibits strong binding affinity on the DNA.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • A Novel Mathematical Model of the Dynamics of COVID-19

    • Authors: Elif DEMİRCİ
      Abstract: The severity of the COVID-19 pandemic requires a better understanding of the spread of SARS-COV2. As of December 2019, several mathematical models have been developed to explain how SARS-COV2 spreads within populations, and proposed models have evolved as more is learned about the dynamics of the outbreak. In this study, we propose a new mathematical model that includes demographic characteristics of the population. Social isolation and vaccination are also taken into account in the model. Besides transmission arising from intercourse with undiagnosed infected persons, we also consider transmission by contact with the exposed group. In this study, after the model is established, the basic reproduction number is calculated and local stability analysis of disease-free equilibrium is given. Finally, we give numerical simulations for the proposed model.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Rotor Field-Oriented Control of Doubly Fed Induction Generator in Wind
           Energy Conversion System

    • Authors: Zeki OMAÇ; İrfan ERDEM
      Abstract: In this study, robust and high-performance vector control of a rotor side converter (RSC) was performed for stability and efficient operation doubly fed induction generator (DFIG) based on the variable speed wind turbine (VSWT). The mathematical model of the DFIG is simulated in the computer. Amplitude and frequency of the voltage in the DFIG were controlled for different values of load and variable speeds. In the experimental study, a DFIG-based wind turbine system was set up in the laboratory. The field position of the stator was detected from stator voltages by a phase-locked loop (PLL) circuit. The rotor position was measured with an incremental encoder connected to the rotor shaft of the DFIG. The angular position of the slip was calculated by the difference between the rotor and the stator field positions. The frequency and amplitude of rotor currents were determined with the angular position of slip. To generate output voltages of converter feeding rotor windings, the space vector pulse width modulation (SVPWM) technique was used. In the experimental study, the RSC was controlled with the DS1103 board. The prepared experiment set was tested at different operating speeds.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Design and Implementation of MRAC & MRAC-PID Feedback for Turntable

    • Authors: Saıbal MANNA; Deepak Kumar SİNGH, Ashok Kumar AKELLA
      Abstract: The paper explains a control method for turntable by feedback a PID controller with the traditional model reference adaptive controller (MRAC) based on the MIT rule. The traditional MRAC is designed for a first-order system with the adjustment of a two-variable parameter. However, the majority of plants, including turntable, are second-order systems. Traditional MRAC tracking performance for second-order systems is unsatisfactory. The control law for the second order system along with extension from the first to the second order of MRAC is derived. The modified MRAC i.e., MRAC-PID controller is designed for the application of turntable. It enhanced the system’s dynamic performance. To assess the performance of the proposed controller, MATLAB/Simulink software was used. The article incorporates a detailed analysis and comparison of PID, MRAC as well as MRAC-PID controllers based on the MIT rule for the turntable system. The robustness of the proposed controller is validated by introducing uncertainties in two aspects i.e., mistuning of the controller gains and turntable system dynamics change. The probabilistic design assessment for the mistuning is carried out through levels of uncertainty in controller gain. It is observed that PID and MRAC would track the reference model but modified MRAC has better performance in terms of tracking accuracy, adaptability, and rapidity. Several performance indexes such as integral absolute error (IAE), integral time absolute error (ITAE), and integral square error (ISE) were employed to justify the proposed controller superiority.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • 3D Stochastic Network Modeling and Investigation of Network Size Effect on
           the Porous Media Structure of Ion Exchange Catalyst Amberlyst-35 with
           Computer Programs

    • Authors: Veli ŞİMŞEK; Kırali MURTEZAOĞLU
      Abstract: In the present paper, the investigation was focused on the physical characterization and determination of porosity for an ion exchange catalyst called Amberlyst-35, which produces environmentally benign gasoline using 3D network modeling (3DNM). In addition, the effect of the different pore size distributions (PSD) has been investigated in porous media (PM). First, the mercury porosimetry (MPo) experiment was carried out to determine the porosity of the Amberlyst-35. Second, the KALINET program was run by Compact Visual Fortran (CVF) and Graphical Input/Output (GINO) for modeling porous structures. Then, the SECTION program was used for different porous 3D random images. The theoretical penetration curve was drawn using data obtained from the KALINET program and fitted to the experimental penetration values of Amberlyst-35 by changing the number of pores in each pressure interval of the PSD. The PSD was a 3D network model size of (N) = 30x30x30, 40x40x40, 50x50x50, which included 83,700-196,800-382,500 pores, respectively. On the other hand, various sections of the 3D stochastic images of the pore network were obtained from the SECTION program. Finally, 3D network images were drawn by the KALINET3D computer program. The MPo method has been applied using computer programs (with desktop computers). Moreover, it was found that the same results were obtained for both the theoretical and experimental data of MPo.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • ANN Identification technique and fuzzy PI Control of a Hybrid Indirect
           Matrix Converter with a Flying Capacitor three level Inverter in Power
           Active Filtering Application

    • Authors: Taki Eddine AMEUR; Aissa AMEUR, Benalia ATALLAH
      Abstract: The current paper is concerned with fuzzy controllers employing neural networks to implement control over power electronics systems committed to power quality improvement in a distribution grid. An optimization method technique for tuning fuzzy PI controller gains is introduced to improve a Hybrid Indirect Matrix Converter's control with a flying capacitor three-level inverter (HIMC), and it is connected via an RL filter to the power grid (PG). The harmonics are identified by an Artificial Neural Network (ANN). The effectiveness of this method is shown in the simulation results by MATLAB/Simulink ( Simscap, simpower blocks).
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Numerical Analysis of Air Flow in an Industrial Refrigeration System and
           Its Effect on Energy Consumption

    • Authors: Serhat KARYEYEN; Mustafa AKTAŞ, Alperen OKUR, Fatma Nur ERDOĞMUŞ
      Abstract: Refrigerated display cabinets as a type of cooling system is preferable commonly in food shops and grocery store to prevent foods from warm air. They do not have much more efficient compared to the cabinets with glass doors because of the interactions between air curtain. This paper presents experimental and numerical methods to seek energy performance of the horizontal refrigerated display cabinets in terms of design parameters. Two geometry with/without airfoil were designed and evaluated the effects of discharge velocity to create more efficient air curtain. 2D Computational Fluid Dynamics (CFD) model was performed to assess the effect of discharge flow on the cooling load performance of the horizontal display cabinet. The results showed that the airfoil design has increased the efficiency of the air curtain with achieving a more effective air curtain, resulted in mitigation of the ambient warm air infiltration into the cabinet. The return air temperature of the cabinet with airfoil decreased from 272.45 K to 270.62 K compared to the one without airfoil due to more effective air curtain. In this way, the cooling capacity of the refrigeration system has been decreased by 3.82% with airfoil usage. It is also concluded that the air temperature inside the cabinet and the cooling capacity have been decreased by 3.5°C and 2.82%, respectively when Case 7 for used the new type airfoil and Case 1 with the same air velocity are compared.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • A Fuzzy Logic Approach and Path Algorithm for Time and Energy Management
           of Smart Cleaning Robots

    • Authors: Hakan ŞİMŞEK; Faize Nur ERTÜRK, Recep ŞEKER
      Abstract: Smart home technologies (SHM) or devices provide some degree of digitally connected, automated, or enhanced services to building occupants in residential areas and have been becoming increasingly popular in recent years. SHM have the potential to improve home comfort, convenience, security, and energy management. Different technologies are used to equip household parts for smarter monitoring, movement, and remote control and to allow effective harmonic interaction between them. Especially, energy management and path-planning algorithms are some of the important problems for such technologies to get optimum efficiency and benefit. Smart vacuum cleaning robot is one of the applications of such devices with various functions. These cleaning robots have limited battery power and battery sizes, thus effective cleaning is critical. Additionally, the shortest / optimal path planning is essential for the efficient operation of effective cleaning based on the battery time. In this article, two distinct algorithms, which are Search algorithm and CSP algorithm are utilized to obtain distinct optimal minimum path lengths for keeping the home's total dirt level as low as possible. Depending on various types of linguistic, abstract, or perceptual variables, these algorithms are not enough for the energy management of the battery. Therefore, the fuzzy logic-based inference system is proposed for obtaining the charge durability of battery of the cleaning robot, in addition to these algorithms. The inputs affecting the charge durability are considered as floor type, dirt level and the width of area for the fuzzy approach.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Determination freeze-drying characteristics of ottoman strawberries

    • Authors: Bahadir ACAR; Abdullah DAĞDEVİREN, Büşra Meryem YILDIZ, Prof. Dr. Mehmet ÖZKAYMAK
      Abstract: This study was performed to define the kinetic drying model and to define the effective diffusivity coefficient of the fruit, which is called ottoman strawberries in the literature. In the study, strawberries by the weight of 100 g and with a thickness of 5 mm were placed in the drying device, and the data were processed by observing the weight loss every two hours after being subjected to the drying process for 14 hours. 8 different kinetic drying models were applied to the acquired data using the MATLAB program. As a result of the application, the estimated standard errors (RMSE), chi-square (X2), regression coefficients (R2) were calculated, error analysis was performed, R2, X2, and RMSE values were found, as 9,998×10-1, 6,993×10-5 and 0.7242×10-2. According to these results, the model of strawberry was determined that the most suitable model is the Page model. Also, the effective diffusivity coefficients for ottoman strawberries were calculated as 2.73286 × 10-10 m2/s. It was confirmed that the calculated effective diffusivity value was within the reference range mentioned in the literature (10-12 m2/s – 10-8 m2/s) for food products.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • An Analysis of DoS Attack on Robot Operating System

    • Authors: Elif DEĞİRMENCİ; Yunus Sabri KIRCA, Esra N. YOLAÇAN, Ahmet YAZİCİ
      Abstract: The emergence of robotic technologies has made a significant contribution in industry. Robot Operating System (ROS) is becoming a standard framework for industrial systems uses as a middleware system with many versions. However, the initial design of ROS does not include cyber-security concepts. The intense interest in robot systems, the security concerns and vulnerabilities of these systems have started to attract the attention of attackers. One of these attacks is DoS attack that targeting system availability by slowing down or crashing a service rather than obtaining the information or system. In this study, the impact of DoS attack has been analyzed in various scenarios for both in application and transport layer of the ROS middleware.In the experiments four different volume of DoS attacks are performed in five different experiment scenarios on ROS. To understand the impact of DoS attack, network traffics are monitored using Tshark. The resulting effects measured with some Quality of Service parameters that are delay and packet loss. 
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • A Systematic Review of Transfer Learning-Based Approaches for Diabetic
           Retinopathy Detection

    • Authors: Burcu OLTU; Büşra Kübra KARACA, Hamit ERDEM, Atilla ÖZGÜR
      Abstract: Diabetic retinopathy, which is extreme visual blindness due to diabetes, has become an alarming issue worldwide. Early and accurate detection of DR is necessary to prevent the progression and reduce the risk of blindness. Recently, many approaches for DR detection have been proposed in the literature. Among them, deep neural networks (DNNs), especially Convolutional Neural Network (CNN) models, have become the most offered approach. However, designing and training new CNN architectures from scratch is a troublesome and labor-intensive task, particularly for medical images. Moreover, it requires training tremendous amounts of parameters. Therefore, transfer learning approaches as pre-trained models have become more prevalent in the last few years. Accordingly, in this study, 43 publications based on DNN and Transfer Learning approaches for DR detection between 2016 and 2021 are reviewed. The reviewed papers are summarized in 4 figures and 10 tables that present detailed information about 29 pre-trained CNN models, 13 DR data sets, and standard performance metrics. 
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Discrete-Time Gompertz Model for Adana Breed Pigeons

    • Authors: Levent ÖZBEK
      Abstract: The mathematical animal growth models in the literature are not in the form of linear models. These growth models in the literature are not in linear form. There are different numerical analysis methods for the estimation of the parameters found in these functions and specific software have been produced to estimate the unknown parameters in these mathematical models and to apply these methods. In these nonlinear mathematical growth models, there may be more than one parameter. For these and other reasons, the number of mathematical numerical operations in estimating parameters is quite high. In this study, the discrete time stochastic Gompertz model (DTSGM) was considered to determine the growth of Adana pigeons. A model is used in which the parameter in the model is estimated by an adaptive Kalman filter (AKF). The aim of this research is to reveal the validity of both the model and the estimation method for Adana breed domestic pigeons. Daily weight measurements of 28 Adana pigeons were considered and estimated using DTSGM and AKF methods in this framework. DTSGM in conjunction with AKF has been shown to provide a convenient analysis tool for modeling daily weight estimates of Adana pigeons.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Framework for Heterogeneous Sensor Data Stream Management with BIM and WSN

    • Authors: Ozgun PINARER
      Abstract: By the 2010s, BIM is highly popular research area that gathers researchers from various domains. We tackle the major challenge of BIM and the main barrier for the application of BIM in smart environments: integration of BIM and wireless sensor networks. Existing studies in the literature have various dependencies and propose limited solutions. These solutions are dedicated to specific applications and domains. However, it is highly required to have a generic solution for real time indoor and outdoor environmental monitoring with full integration with the digital model of the building. To fulfill this need, in this study, we propose a novel approach to monitor and fulfill user requirements by a numerical model of the building, a novel framework and a BIM-WSN integrated architecture based on the BIM principles for smart building environments. All the experiments are performed on a real testbed, physical sensor devices deployed on the classrooms of the university building. Such numerical model presents the digital model of the environment by gathering acquired data. Besides, data is gathered on a big data platform where it may be served to various other applications such as machine learning studies.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • A Comparative Study on Denoising from Facial Images Using Convolutional

    • Authors: Muazzez Buket DARICI; Zeki ERDEM
      Abstract: Denoising is one of the most important preprocesses in image processing. Noises in images can prevent extracting some important information stored in images. Therefore, before some implementations such as image classification, segmentation, etc., image denoising is a necessity to obtain good results. The purpose of this study is to compare the deep learning techniques and traditional techniques on denoising facial images considering two different types of noise (Gaussian and Salt&Pepper). Gaussian, Median, and Mean filters have been specified as traditional methods. For deep learning methods, deep convolutional denoising autoencoders (CDAE) structured on three different optimizers have been proposed. Both accuracy metrics and computational times have been considered to evaluate the denoising performance of proposed autoencoders, and traditional methods. The utilized standard evaluation metrics are the peak signal to noise ratio (PSNR) and structural similarity index measure (SSIM). It has been observed that overall, while the traditional methods gave results in shorter times in terms of computation times, the autoencoders performed better concerning the evaluation metrics. The CDAE based on the Adam optimizer has been shown the best results in terms of PSNR and SSIM metrics on removing both types of noise.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • New Ostrowski Type Inequalities for Trigonometrically Convex Functions Via
           Classical Integrals

    • Authors: Şenol DEMİR; Selahattin MADEN
      Abstract: In the paper, we introduce the class of trigonometrically convex functions and using the Hölder, Hölder-Işcan, Power-mean and Improved power-mean integral inequality together with an identity we establish some new inequalities of Ostrowski-type for functions whose second derivatives are trigonometrically convex which is a special case of h-convex functions. Some applications for special means are also given.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • A Comparative Assessment of Five Different Distributions Based on Five
           Different Optimization Methods for Modeling Wind Speed Distribution

    • Authors: Mohammed WADİ; Wisam ELMASRY
      Abstract: Determining wind regime distribution patterns is essential for many reasons; modelling wind power potential is one of the most crucial. In that regard, Weibull, Gamma, and Rayleigh functions are the most widely used distributions for describing wind speed distribution. However, they could not be the best for describing all wind systems. Also, estimation methods play a significant role in deciding which distribution can achieve the best matching. Consequently, alternative distributions and estimation methods are required to be studied. An extensive analysis of five different distributions to describe the wind speeds distribution, namely Rayleigh, Weibull, Inverse Gaussian, Burr Type XII, and Generalized Pareto, are introduced in this study. Further, five metaheuristic optimization methods, Grasshopper Optimization Algorithm, Grey Wolf Optimization, Moth-Flame Optimization, Salp Swarm Algorithm, and Whale Optimization Algorithm, are employed to specify the optimum parameters per distribution. Five error criteria and seven statistical descriptors are utilized to compare the good-of-fitness of the introduced distributions. Therefore, this paper provides different important methods to estimate the wind potential at any site.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Comparison of the Performance of Solar Panels Designed in Three Different
           Ways under the Same Conditions

    • Authors: Mehmet Ali SALDAMLI; Yusuf Alper KAPLAN, Gülizar Gizem ÜNALDI
      Abstract: Renewable energy sources such as solar energy have great potential to alleviate some of the negative environmental problems, including climate change, caused by intensive fossil fuel use. Solar energy will play an important part in future energy systems because of its rapid installation technology and lowering costs. In order to use solar radiation intensity in a wide range in the most efficient way, the plants must either be at an optimum angle in the area where they are installed or they should be designed with moving systems. In this study, performance and efficiency comparisons of solar tracking systems and fixed-designed systems based on real-field conditions have been made. In this way, price performance ratios can be determined clearly and it will be easier to decide on the types of power plants to be built. While solar tracking systems move according to the most efficient position that they can get from the sun through radiation sensors, they are designed with elements such as PLCs using multi-year solar data that operate with an open loop and based on meteorological data. In this study, three different power plant types designed as 1-axis, 2-axis, and fixed angle were controlled as open loop with PLC software and production differences between power plants were evaluated for 1 year. According to this research we have done, it has been concluded that 2-axis tracking systems produce approximately 32% more energy annually than a fixed-angle system, with an annual efficiency rate of 23% higher than a 1-axis system.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Indoor Lighting Conversion Approach for Sustainable Energy Efficiency
           Applications in Campus Buildings: Hitit University Engineering Faculty

    • Authors: Sertac Samed SEYITOGLU; Ömer Faruk TOZLU, Emir AVCIOĞLU
      Abstract: Global energy crises, limited energy resources and damage to nature in energy production have pushed humanity to use energy more efficiently and renewable energy sources. In this context, the importance of implementing energy efficiency and sustainable strategies in buildings that consumes high energy has increased. In this study, the effect of luminaires substitution with more efficient ones and electricity production by renewable energy sources on efficiency, sustainability and environment was examined on a sample education building. The calculations were made according to standards and equipment supplier data. As a result of this study, it has been found that the use of high-efficiency LED lighting instead of halogen or fluorescence luminaires in the engineering faculty building and laboratory of Hitit University, will reduce electricity consumption by 68.2%. In addition, it has been deduced that the solar energy system to be installed on the faculty’s roof, will significantly reduce CO2 emission, and has a payback period of 5.5 years. In terms of gas emissions, a roof-mounted solar energy system is 21, 45, and 32 times less hazardous to the environment than natural gas, lignite, and fuel oil, respectively.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Lumbar Spinal Stenosis Analysis with Deep Learning Based Decision Support

    • Authors: Sinan ALTUN; Ahmet ALKAN
      Abstract: Lumbar spinal stenosis (LSS) is a condition that affects the quality of life of the 3 vertebrae, the disc and the canal in the lower back. In this region, the nerves in the canal may be subjected to pressure for various reasons, and disease occurs. Surgical intervention is required to treat canal stenosis, and the exact location and size of the spinal stenosis is critical to the surgery. The UNet model, which is an example of this network, can be further deepened with various deep learning networks. In this study, it will be the basis for creating a system that helps in the diagnosis of spinal stenosis by using a deeper network. The ResUNET model using ResNet as the backbone achieved an average IoU of 0.987. This study demonstrated that expert decision support systems using MR images can be used in the diagnosis of LSS.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Characterization of Divalent Metal Soaps of Cannabis Sativa Seed Oil

    • Authors: Senem YETGİN; Theresa O. EGBUCHUNAM, Felix OKİEİMEN, Kutalmış GÖKKUŞ, Kerim GÜNEY
      Abstract: In this study, the structural characteristics and thermal degradation behaviour of barium, calcium and zinc soaps of hemp seed oil prepared using the metathesis method are reported. Scanning electron micrographs of the metal soaps showed similar plate-like microstructures and are indicative of an orderly packed particulate structure. The bands at 1509, 1539 and 1543 cm-1 in the FTIR spectra showed the association of the carboxylate ion with Ba, Ca and Zn ions respectively The thermal decomposition consisted of one single step on the weight loss – temperature curves located around 250 – 450 oC for all the divalent metal soaps at the various heating rates and the observed loss in weight which occurred before 200 oC was minimal (< 10%). The average values of the apparent activation energy for the thermal process were 18.73, 13.77 and 8.48 kJ/mol for Zn-HSO, Ca-HSO and Ba-HSO respectively. 
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Synchronization Analysis of a Master-Slave BEC System via Active Control

    • Authors: Eren TOSYALI; Fatma AYDOĞMUŞ
      Abstract: This paper will focus on theoretical treatment of the dynamic of the Bose-Einstein Condensate (BEC) systems contained different external trapping potentials. We construct the phase space diagrams and Lyapunov Characteristic Exponents (LCEs) for master and slave systems depended on the system parameters and propose a nonlinear control for the synchronization of systems in their chaotic states. The synchronization is obtained in master-slave scheme for different initial values. Numerical results are also given to show the efficiency of the used control technique. 
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Dynamics of Web 2.0: A Software Application "Web 2.0 Meter"

    • Authors: Cem Ufuk BAYTAR
      Abstract: In this study, it is intended to understand the concept of Web 2.0 and to introduce its effects on the web design. In the first part of the article, necessary information is provided about relevant topics such as, Web design, the features of Web 1.0, Web 1.5 and Web 2.0 sites and the visual, social and technological implications of the Web 2.0 concept. In the second art of the article, a survey, which includes 21 questions related to Web 2.0 features, was conducted to 150 people having the internet background. This survey is applied for three web sites whose categories are accepted as Web 1.0, Web 1.5 and Web 2.0 in literature. Also, a test program called Web 2.0 Meter is developed with .Net technology to determine the category of a website and to produce comments about the necessary Web 2.0 features that the relevant web site should have. The answers given to questions were processed by Web 2.0 Meter. Consequently, the results show that Web 2.0 Meter has evaluated the category of a website in a proper way.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Effect of Post-thermal Annealing on the Structural, Morphological, and
           Optical Properties of RF-sputtered In2S3 Thin Films

    • Authors: Neslihan AKCAY; Berkcan ERENLER, Yunus ÖZEN, Valery GREMENOK, Konstantin Pavlovich BUSKIS, Süleyman ÖZÇELİK
      Abstract: Indium sulfide films were deposited by radio frequency magnetron sputtering technique on soda lime glass substrate. The deposition was conducted at the temperature of 150 °C and prepared films were then thermally annealed under argon atmosphere at 350 °C and 450 °C for 30 min. The impact of post-thermal annealing treatment on the properties of the films was investigated. From X-ray diffraction analysis, the formation of the stable tetragonal β-In2S3 crystal structure was substantiated and revealed that the thermal annealing treatment at 450 °C improved the crystallization of the films. The change in surface topographies and morphologies of the films depending on the post-thermal annealing process were examined by atomic force microscopy and scanning electron microscopy techniques, respectively. The stoichiometric ratio of constituent elements in the films was obtained by elemental analysis and it was seen that the films had slightly sulfur (S) deficit composition. It was found that the concentration of S slightly increased with the thermal annealing process. The room temperature photoluminescence spectra revealed that the films included vacancies of sulfur (VS: donor) and indium (In) (VIn: acceptor), indium interstitial (Ini: donor) and oxygen (O) in vacancy of sulfur (OVs: acceptor) defects with strong and broad emission bands at around 1.70, 2.20, and 2.71 eV.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Integral Fuzzy Sliding Mode Controller for Hydraulic System Using Neural
           Network Modelling

    • Authors: Ayça AK; Erdal YILMAZ, Sevan KATRANCIOĞLU
      Abstract: In this paper, a hydraulic motor controller is designed with a fuzzy supported integral sliding mode algorithm. The hydraulic system used in the study was modeled using artificial neural networks. Ability of handling nonlinearity of systems makes sliding mode controller to be a good choose for this system. The integral sliding mode controller can supply the robustness the system against the uncertainties. The basic idea of the proposed control method is to use fuzzy logic for the adaptation of the integral sliding mode control switching gain. Such adjustment reduces the chattering that is the most problem of classical sliding mode control. The equivalent control is computed using the radial basis function neural network. Simulation results of the presented method were compared with conventional PID controller results. It proved that it is more efficient to control the hydraulic system with integral fuzzy sliding mode control using neural network.
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
  • Geometric Patterns Used in the Architecture of Kaboud Mosque in Tabriz,

    • Authors: Mahya GHOUCHANİ; Faeze GHOLİZADE, Hooman SOBOUTİ
      Abstract: Doubts about the architectural style of the Kaboud Mosque in Tabriz are related to the geometry of the plan and its special volumetric composition, which has made this building different from other examples of mosque architecture in Iran. For this reason, some scholars, following the formal origins of this mosque, have traced its roots in the art of the Ottoman region and, as a result, have introduced the architecture of the Kaboud Mosque as an imitation of Ottoman architecture. In the present study, using a descriptive-analytical method, the form of the construction of the Kaboud Mosque of Tabriz and its comparison with the Ottoman mosques have been studied and recognized. Then, the geometry used in the Kaboud Mosque of Tabriz has been analyzed by measuring its degree of compatibility with the resulting rectangles of regular pentagons and hexagons. The results show that the construction of the Kaboud Mosque is similar in form to some Ottoman architectural works. However, structurally, it has been created entirely based on the Iranian engineering style. The architectural style of this building, although it opened a new chapter in the design of the mosque in Iranian architecture, could not arouse the desire of later architects to repeat its form. 
      PubDate: Fri, 01 Sep 2023 00:00:00 +030
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