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Full-Text Articles in Physical Sciences and Mathematics

Power Flow Controlling Using Sssc Based On Matrix Converter Via Sa-Pso Algorithm, Ali Ajami, Farhad Mohajel Kazemi Jan 2016

Power Flow Controlling Using Sssc Based On Matrix Converter Via Sa-Pso Algorithm, Ali Ajami, Farhad Mohajel Kazemi

Turkish Journal of Electrical Engineering and Computer Sciences

The static synchronous series compensator (SSSC) is one of the series flexible AC transmission system (FACTS) devices that can be used in power flow control and reactive compensation in transmission lines. In this paper, a new configuration of SSSC based on a matrix converter is presented. The proposed SSSC has some advantages such as elimination of the DC link, bidirectional power flow control capability, fast dynamic response, and simple control system. By presenting a switching algorithm for the AC-AC matrix converter, an almost sinusoidal series compensation voltage is injected to the transmission line with low total harmonic distortion. In this …


Improved Control Of A Photovoltaic Pumping System By Dtc-Svm To Optimize The Water Flow, Moulay Idriss Chergui Jan 2016

Improved Control Of A Photovoltaic Pumping System By Dtc-Svm To Optimize The Water Flow, Moulay Idriss Chergui

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with two different techniques of vector method-related direct torque control: the conventional (DTC-C) and the space vector modulation (DTC-SVM). Both are used for an induction motor in the photovoltaic pumping system. Based on instantaneous space vector theory, and with an optimal selection of the space voltage vectors in each sampling period, the DTC achieves effective control of the stator flux and torque. Consequently, the number of space voltage vectors and switching frequency directly influence the performance of the DTC control system, giving an advantage for a rotor position free control system. In order to improve the efficiency …


Comparison Of Ar Parametric Methods With Subspace-Based Methods For Emg Signal Classification Using Stand-Alone And Merged Neural Network Models, Mehmet Recep Bozkurt, Abdülhami̇t Subaşi, Etem Köklükaya, Mustafa Yilmaz Jan 2016

Comparison Of Ar Parametric Methods With Subspace-Based Methods For Emg Signal Classification Using Stand-Alone And Merged Neural Network Models, Mehmet Recep Bozkurt, Abdülhami̇t Subaşi, Etem Köklükaya, Mustafa Yilmaz

Turkish Journal of Electrical Engineering and Computer Sciences

This research introduces an electromyogram (EMG) pattern classification of individual motor unit action potentials (MUPs) from intramuscular electromyographic signals. The presented technique automatically classifies EMG patterns into healthy, myopathic, or neurogenic categories. To extract a feature vector from the EMG signal, we use different autoregressive (AR) parametric methods and subspace-based methods. The proposal was validated using EMG recordings composed of 1200 EMG patterns obtained from 7 healthy, 7 myopathic, and 13 neurogenic-disordered people. A feedforward error backpropagation artificial neural network (FEBANN) and combined neural network (CNN) were used for classification, where the success rate was slightly higher in CNN. Among …


Scalable Sentiment Analytics, Aslan Baki̇rov, Kevser Nur Çoğalmiş, Ahmet Bulut Jan 2016

Scalable Sentiment Analytics, Aslan Baki̇rov, Kevser Nur Çoğalmiş, Ahmet Bulut

Turkish Journal of Electrical Engineering and Computer Sciences

Spark has become a widely popular analytics framework that provides an implementation of the equally popular MapReduce programming model. Hadoop is an Apache foundation framework that can be used for processing large datasets on a cluster of computers using the MapReduce programming model. Mahout is an Apache foundation project developed for building scalable machine learning libraries, which includes built-in machine learning classifiers. In this paper, we show how to build a simple text classifier on Spark, Apache Hadoop, and Apache Mahout for extracting out sentiments from a text collection containing millions of text documents. Using a collection of 7 million …


Study Of The Icing Growth Characteristic And Its Influencing Factors For Different Types Of Insulators, Zhijing Zhang, Dongdong Zhang, Haizhou Huang, Xingliang Jiang, David Wenzhong Gao Jan 2016

Study Of The Icing Growth Characteristic And Its Influencing Factors For Different Types Of Insulators, Zhijing Zhang, Dongdong Zhang, Haizhou Huang, Xingliang Jiang, David Wenzhong Gao

Turkish Journal of Electrical Engineering and Computer Sciences

Icing poses a serious threat to power transmission in many countries. Various studies on the icing mechanism and icing growth process of transmission lines have been carried out all over the world, whereas there are few reports about the icing growth mechanism and its influencing factors on insulators to date. In this paper, artificial tests of insulator icing were carried out; the influences of temperature, median volumetric diameter (MVD), and wind velocity on the icing accretion process, ice shape, and ice type on the surface of insulators were analyzed systematically; and the icing growth performance of different types of insulators …


Bone Age Determination In Young Children (Newborn To 6 Years Old) Using Support Vector Machines, Gür Emre Güraksin, Harun Uğuz, Ömer Kaan Baykan Jan 2016

Bone Age Determination In Young Children (Newborn To 6 Years Old) Using Support Vector Machines, Gür Emre Güraksin, Harun Uğuz, Ömer Kaan Baykan

Turkish Journal of Electrical Engineering and Computer Sciences

Bone age is assessed through a radiological analysis of the left-hand wrist and is then compared to chronological age. A conflict between these two values indicates an abnormality in the development process of the skeleton. This study, conducted on children aged between 0 and 6 years, proposes a computer-based diagnostic system to eliminate the disadvantages of the methods used in bone age determination. For this purpose, primarily an image processing procedure was applied to the X-ray images of the left-hand wrist of children from different ethnic groups aged between 0 and 6 years. A total of 9 features, corresponding to …


An Innovative Peak Detection Algorithm For Photoplethysmography Signals: An Adaptive Segmentation Method, Ahmet Reşi̇t Kavsaoğlu, Kemal Polat, Mehmet Recep Bozkurt Jan 2016

An Innovative Peak Detection Algorithm For Photoplethysmography Signals: An Adaptive Segmentation Method, Ahmet Reşi̇t Kavsaoğlu, Kemal Polat, Mehmet Recep Bozkurt

Turkish Journal of Electrical Engineering and Computer Sciences

The purpose of this paper is twofold. The first purpose is to detect M-peaks from raw photoplethysmography (PPG) signals with no preprocessing method applied to the signals. The second purpose is to estimate heart rate variability (HRV) by finding the peaks in the PPG signal. HRV is a measure of the fluctuation of the time interval between heartbeats and is calculated based on time series between strokes derived from electrocardiogram (ECG), arterial pressure (AP), or PPG signals, separately. PPG is a method widely used to measure blood volume of tissue on the basis of blood volume change in every heartbeat. …


System Identification By Using Migrating Birds Optimization Algorithm: A Comparative Performance Analysis, Hasan Makas, Nejat Yumuşak Jan 2016

System Identification By Using Migrating Birds Optimization Algorithm: A Comparative Performance Analysis, Hasan Makas, Nejat Yumuşak

Turkish Journal of Electrical Engineering and Computer Sciences

System identification is an important process to investigate and understand the behavior of an unknown system. It aims to establish an interface between the real system and its mathematical representation. Conventional system identification methods generally need differentiable search spaces and they cannot be used for nondifferentiable multimodal search spaces. On the other hand, metaheuristic search algorithms are independent from the search space characteristics and they do not need much knowledge about the real system. The migrating birds optimization algorithm is a recently introduced nature-inspired metaheuristic neighborhood search approach. It simulates the V flight formation of migrating birds, which enables birds …


Gravitational Search Algorithm For Determining Controller Parameters In An Automatic Voltage Regulator System, Serhat Duman, Nuran Yörükeren, İsmai̇l Hakki Altaş Jan 2016

Gravitational Search Algorithm For Determining Controller Parameters In An Automatic Voltage Regulator System, Serhat Duman, Nuran Yörükeren, İsmai̇l Hakki Altaş

Turkish Journal of Electrical Engineering and Computer Sciences

proportional-integral-derivate (PID) controller for an automatic voltage regulator (AVR) system using a heuristic gravitational search algorithm (GSA) based on mass interactions and Newton's law of gravity. The determination of optimal controller parameters is considered an optimization problem in which different performance indexes and a performance criterion in the time domain have been used as objective functions to test the performance and effectiveness of the GSA. In the determining process of the parameters, the designed PID controller with the proposed approach is simulated under different conditions and the performance of the controller is compared with those reported in the literature. From …


An Efficient Lof-Based Long-Range Correlation Filter For The Restoration Of Salt And Pepper Impulse Corrupted Digital Images, Justin Varghese, Saudia Subash, Mohamed Samiulla Khan, Krishnan Nallaperumal, Bijoy Babu, Mohammed Ramadan Saadi Jan 2016

An Efficient Lof-Based Long-Range Correlation Filter For The Restoration Of Salt And Pepper Impulse Corrupted Digital Images, Justin Varghese, Saudia Subash, Mohamed Samiulla Khan, Krishnan Nallaperumal, Bijoy Babu, Mohammed Ramadan Saadi

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Fetal Electrocardiogram Estimation Using Polynomial Eigenvalue Decomposition, Soydan Redif Jan 2016

Fetal Electrocardiogram Estimation Using Polynomial Eigenvalue Decomposition, Soydan Redif

Turkish Journal of Electrical Engineering and Computer Sciences

decomposition (PEVD) to the problem of fetal electrocardiogram (ECG) extraction from real ECG recordings obtained from abdominal leads. We model the fetal ECG extraction problem as a broadband sensor array signal processing problem in order to account for the broadband nature of the ECG noise present in the recordings. An algorithm for providing an approximate PEVD is used in order to estimate the broadband noise subspace. Suppression of the broadband noise and maternal ECG is achieved by carrying out an orthonormal projection of the recordings onto the estimated fetal subspace. The proposed scheme was evaluated with multichannel synthetic ECG signals …


Implementation Analyses Of Proteins And Genes Obtained From Cancer Patients, Murat Demi̇r, Ali̇ Karci Jan 2016

Implementation Analyses Of Proteins And Genes Obtained From Cancer Patients, Murat Demi̇r, Ali̇ Karci

Turkish Journal of Electrical Engineering and Computer Sciences

bioinformatics and computational molecular biology, since these studies may result in important results in the case of diseases. Due to this, in this study, bioinformatics data were analyzed based on nucleotides and motifs. Bioinformatics data for proteins were obtained from two different databases. The obtained data belonged to cancer patients, and the genes in these DNA and protein sequences, the proteins synthesized by these sequences, and motifs in these data were analyzed. In the analysis, the ABCB1, ALOX5AP, AKT1, BRCA1, BRCA2, TNF, TNFSF13B, TP53, TP63, TP73, and WT1 genes were used. The proteins synthesized by genes belonging to similar classes …


Effects Of Mica2-Based Discrete Energy Levels On The Lifetime Of Cooperation Neighbor Sensor Networks, Zeydi̇n Pala Jan 2016

Effects Of Mica2-Based Discrete Energy Levels On The Lifetime Of Cooperation Neighbor Sensor Networks, Zeydi̇n Pala

Turkish Journal of Electrical Engineering and Computer Sciences

using Mica2 mote discrete power levels on neighbor sensor network lifetime. We built a linear programming framework to qualify the cooperation of sensor networks using a discrete energy model in comparison to noncooperating networks. Our results showed that a wireless sensor neighbor network that uses a discrete radio model can be more energy efficient than a network that uses a nondiscrete energy model.


The Optimization Of A Projectile From A Three-Coil Reluctance Launcher, Ferhat Daldaban, Veki̇l Sari Jan 2016

The Optimization Of A Projectile From A Three-Coil Reluctance Launcher, Ferhat Daldaban, Veki̇l Sari

Turkish Journal of Electrical Engineering and Computer Sciences

realization of an experimental prototype. A Maxwell model of the system was constructed and finite elements analysis (FEA) was applied before building the experimental prototype. The effect of variations in projectile parameters (such as material and length of the projectile) on projectile velocity was studied using the model. Then the experimental prototype of the launcher system was built. A velocity measurement system was also designed and implemented to measure the muzzle velocity of the launched projectiles. A total of 9 projectiles of 3 different sizes made of 3 different materials were constructed to be launched by the system. Each projectile …


A New Approach For Edge Detection In Noisy Images Based On The Lpgpca Technique, Şahi̇n Işik, Kemal Özkan Jan 2016

A New Approach For Edge Detection In Noisy Images Based On The Lpgpca Technique, Şahi̇n Işik, Kemal Özkan

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


An Investigation Of Intelligent Controllers Based On Fuzzy Logic And Artificial Neural Network For Power System Frequency Maintenance, Ngockhoat Nguyen, Qi Huang, Thi-Mai-Phuong Dao Jan 2016

An Investigation Of Intelligent Controllers Based On Fuzzy Logic And Artificial Neural Network For Power System Frequency Maintenance, Ngockhoat Nguyen, Qi Huang, Thi-Mai-Phuong Dao

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Power System Harmonic Reduction And Voltage Control Using Dfig Converters As An Active Filter, Seyyed Mostafa Nosratabadi, Eskandar Gholipour Jan 2016

Power System Harmonic Reduction And Voltage Control Using Dfig Converters As An Active Filter, Seyyed Mostafa Nosratabadi, Eskandar Gholipour

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Quantitative Risk Associated With Intermittent Wind Generation, Mohamed Shaaban, Mohd. Dzulhafizi Usman Jan 2016

Quantitative Risk Associated With Intermittent Wind Generation, Mohamed Shaaban, Mohd. Dzulhafizi Usman

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Analyzing The Mutual Authenticated Session Key In Ip Multimedia Server-Client Systems For 4g Networks, Bakkiam David Deebak, Rajappa Muthaiah, Karuppuswamy Thenmozhi, Pitchai Iyer Swaminathan Jan 2016

Analyzing The Mutual Authenticated Session Key In Ip Multimedia Server-Client Systems For 4g Networks, Bakkiam David Deebak, Rajappa Muthaiah, Karuppuswamy Thenmozhi, Pitchai Iyer Swaminathan

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Bbo Algorithm-Based Tuning Of Pid Controller For Speed Control Of Synchronous Machine, Gowrishankar Kasilingam, Jagadeesh Pasupuleti Jan 2016

Bbo Algorithm-Based Tuning Of Pid Controller For Speed Control Of Synchronous Machine, Gowrishankar Kasilingam, Jagadeesh Pasupuleti

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Evolutionary Optimized Discrete Tchebichef Moments For Image Compression Applications, Ragamathunisa Begum Abdul Hameed, Manimegalai Duraisamy, Abudhahir Ameerbasha, Baskar Subramanian Jan 2016

Evolutionary Optimized Discrete Tchebichef Moments For Image Compression Applications, Ragamathunisa Begum Abdul Hameed, Manimegalai Duraisamy, Abudhahir Ameerbasha, Baskar Subramanian

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


A Model For Flipping Electrical Engineering With E-Learning Using A Multidimensional Approach, Dursun Akaslan, Effie Lai-Chong Law Jan 2016

A Model For Flipping Electrical Engineering With E-Learning Using A Multidimensional Approach, Dursun Akaslan, Effie Lai-Chong Law

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a model for supporting electrical engineering with e-learning. The model development is based on survey data collected from representative teachers and students studying in higher education institutions in Turkey. To develop the model, the study investigated the attitudes of the representative key stakeholders in the relevant higher education institutions towards e-learning by administrating questionnaires and interviews with teachers and students. The responses of the teachers and students were then compared. Based on the results, a model was proposed with a multidimensional approach to e-learning. The model flips electrical engineering to make sure that the students review, discuss, …


A Conceptual Implementation Of A Buck Converter For An Off-Grid Hybrid System Consisting Of Solar And Wind Turbine Sources, Ahmad Shukri Fazil Rahman, Abdul Rahim Abdul Razak, Syed Idris Syed Hassan Jan 2016

A Conceptual Implementation Of A Buck Converter For An Off-Grid Hybrid System Consisting Of Solar And Wind Turbine Sources, Ahmad Shukri Fazil Rahman, Abdul Rahim Abdul Razak, Syed Idris Syed Hassan

Turkish Journal of Electrical Engineering and Computer Sciences

A hybrid renewable power generation system is proposed through parallel connection between two potential energy resources: photovoltaic (PV) and wind turbines. The method consists of incorporating a buck converter connected by a wind turbine to provide adjustment according to PV potential. Unlike the conventional buck-boost converter topology that is normally used, this research tries to emphasize the use of a buck converter as part of the system configuration. Design schemes were carefully performed and the postdesign system was tested through system simulation with MATLAB/Simulink software. The simulated system offers promising and significant results, thus making it suitable for hardware implementation.


Modeling And Simulation Of Sensorless Control Of Four-Leg Inverter Pmsm Drives In The Case Of A Single-Phase Open Circuit Fault, Kamel Saleh, Mark Sumner Jan 2016

Modeling And Simulation Of Sensorless Control Of Four-Leg Inverter Pmsm Drives In The Case Of A Single-Phase Open Circuit Fault, Kamel Saleh, Mark Sumner

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces a new method to track the saliency of a permanent magnet synchronous motor (PMSM) motor fed by a 4-leg inverter in the case of a single-phase open circuit fault through measuring the dynamic current response of the motor line currents due to the insulated-gate bipolar transistor (IGBT) switching actions. In the case of a single-phase open circuit fault, a fault-tolerant control strategy that includes taking appropriate actions to control the 2 remaining healthy currents results in minor system performance degradation. The new strategy introduced in this paper includes software modifications only to the saliency tracking algorithm used …


A Multiobjective Tuning Approach Of Power System Stabilizers Using Particle Swarm Optimization, Hilal Labdelaoui, Fares Boudjema, Djamel Boukhetala Jan 2016

A Multiobjective Tuning Approach Of Power System Stabilizers Using Particle Swarm Optimization, Hilal Labdelaoui, Fares Boudjema, Djamel Boukhetala

Turkish Journal of Electrical Engineering and Computer Sciences

This work presents an optimal tuning approach of power system stabilizers (PSSs) using multiobjective particle swarm optimization. Two types of PSSs are investigated, the conventional speed-based PSS type and a dual-input PSS type that uses the accelerating power as an additional input. The tuning problem of these PSSs is formulated as a minimization problem of a vector objective function characterizing the damping and the transient performance of the closed-loop system. A 3-machine 9-bus power system example is considered, and the speed-constrained multiobjective particle swarm optimization algorithm is used to solve the optimization problem. The results show that trade-offs exist between …


Optimization Of An Experimental Unsymmetrical-Unbalanced Two-Phase Induction Motor Using The Hgapso Hybrid Technique And The Finite Element Method For Increasing Efficiency And Reducing Torque Ripple, Navid Horiyat, Seyed Mohammad Shariatmadar, Vahid Amir Jan 2016

Optimization Of An Experimental Unsymmetrical-Unbalanced Two-Phase Induction Motor Using The Hgapso Hybrid Technique And The Finite Element Method For Increasing Efficiency And Reducing Torque Ripple, Navid Horiyat, Seyed Mohammad Shariatmadar, Vahid Amir

Turkish Journal of Electrical Engineering and Computer Sciences

Two-phase induction motors make an important contribution to social welfare. Accordingly, enhanced quality in such motors would benefit society. This study was done to test this type of motor to determine a nonlinear optimal point in the form of a multiobjective function between ripple of the torque and motor efficiency with consideration of a weighted coefficient in an unbalanced-unsymmetrical two-phase induction motor. Tests demonstrated that minimizing total harmonic distortion could reduce torque ripple. The optimal point was determined using optimization algorithms, and a hybrid of genetic and particle swarm optimization algorithms simultaneously in order to increase efficiency and to reduce …


Hardware Implementation Of A Scale And Rotation Invariant Object Detection Algorithm On Fpga For Real-Time Applications, Murat Peker, Hali̇s Altun, Fuat Karakaya Jan 2016

Hardware Implementation Of A Scale And Rotation Invariant Object Detection Algorithm On Fpga For Real-Time Applications, Murat Peker, Hali̇s Altun, Fuat Karakaya

Turkish Journal of Electrical Engineering and Computer Sciences

A hardware implementation of a computationally light, scale, and rotation invariant method for shape detection on FPGA is devised. The method is based on histogram of oriented gradients (HOG) and average magnitude difference function (AMDF). AMDF is used as a decision module that measures the similarity/dissimilarity between HOG vectors of an image in order to classify the object. In addition, a simulation environment implemented on MATLAB is developed in order to overcome the time-consuming and tedious process of hardware verification on the FPGA platform. The simulation environment provides specific tools to quickly implement the proposed methods. It is shown that …


A Monte Carlo-Based Poisson's Equation Solver Parallelized With Coarray Fortran, Nevsan Şengi̇l, Özgür Tümüklü, Mehmet Cevdet Çelenli̇gi̇l Jan 2016

A Monte Carlo-Based Poisson's Equation Solver Parallelized With Coarray Fortran, Nevsan Şengi̇l, Özgür Tümüklü, Mehmet Cevdet Çelenli̇gi̇l

Turkish Journal of Electrical Engineering and Computer Sciences

Poisson's equation is found in many scientific problems, such as heat transfer and electric field calculations. Although many different techniques are involved in solving Poisson's equation, we focused on the Monte Carlo method (MCM). We preferred the MCM not only because of its simple algorithm but also for its excellent parallel efficiency. Parallelization is one of the most effective techniques for reducing computation time. Among many parallelization paradigms, such as OpenMP (open multiprocessing), MPI (message passing interface), and PGAS (partitioned global address space), we adopted the PGAS-based Coarray Fortran (CAF). In this paper, we demonstrated that parallelization of Poisson's equation …


A Comprehensive Control Strategy Of Railway Power Quality Compensator For Ac Traction Power Supply Systems, Hamed Jafari Kaleybar, Siamak Farshad Jan 2016

A Comprehensive Control Strategy Of Railway Power Quality Compensator For Ac Traction Power Supply Systems, Hamed Jafari Kaleybar, Siamak Farshad

Turkish Journal of Electrical Engineering and Computer Sciences

The development of electrical railway systems leads to critical power quality problems in the power grid. This paper discusses a kind of half-bridge-based railway power quality compensator system (HBRPQC) that can compensate negative sequence currents, harmonics, and reactive power simultaneously. In order to keep the HBRPQC performance efficient for the different kinds of transformers used in traction power supply substations, a new multifunctional control strategy that performs better than previous methods is proposed. Due to the fast dynamicity of traction loads, a recessive self-tuning PI controller based on fuzzy logic is adopted in the current control system. The output control …


An Interval-Based Contingency Selection Approach Considering Uncertainty, Chao Xu, Wei Gu, Lizi Luo, Jianguo Yao, Shengchun Yang, Ke Wang, Dan Zeng, Miao Fan Jan 2016

An Interval-Based Contingency Selection Approach Considering Uncertainty, Chao Xu, Wei Gu, Lizi Luo, Jianguo Yao, Shengchun Yang, Ke Wang, Dan Zeng, Miao Fan

Turkish Journal of Electrical Engineering and Computer Sciences

Static security assessment is affected by uncertainties of load flow distributions introduced by renewable sources. A fast contingency selection approach based on interval theory is proposed in this paper. Firstly, an interval line active flow calculation algorithm is developed to reduce conservation in application of interval mathematics in line flow calculation. Then a novel interval comparison method based on Bayesian probability theory is applied in interval index comparison to give the relative severity information of contingencies. Finally, an approximately consistent ranking method is utilized in contingency ranking to rank screened contingencies. Numerical studies on several IEEE standard test systems and …