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Full-Text Articles in Physical Sciences and Mathematics

Improving The Srf Method To Compensate Low-Order Harmonics Under Nonsinusoidal Network Voltages, Javad Modarresi, Mehdi Fallah, Eskandar Ghokipour, Mohammad Tavakoli Bina Jan 2016

Improving The Srf Method To Compensate Low-Order Harmonics Under Nonsinusoidal Network Voltages, Javad Modarresi, Mehdi Fallah, Eskandar Ghokipour, Mohammad Tavakoli Bina

Turkish Journal of Electrical Engineering and Computer Sciences

Increasing the application of power in electronic devices has increased the harmonics in power systems. Numerous methods like the synchronous reference frame (SRF) and the p-q-based method have been suggested to overcome the effects of these harmonics. The conventional SRF method provides acceptable results in harmonic compensation of high-order harmonics (higher than the fourth order), but the transient response time will be drastically increased in the presence of low-order harmonics due to the existence of a conventional low-pass filter. Furthermore, if the load terminal voltages are distorted, then the conventional SRF method will become unable to implement load current compensation. …


Empirical Mode Decomposition Application For Short-Term Flicker Severity, Yasemi̇n Önal, Ömer Nezi̇h Gerek, Doğan Gökhan Ece Jan 2016

Empirical Mode Decomposition Application For Short-Term Flicker Severity, Yasemi̇n Önal, Ömer Nezi̇h Gerek, Doğan Gökhan Ece

Turkish Journal of Electrical Engineering and Computer Sciences

In this article, an approach based on empirical mode decomposition (EMD) is suggested in order to calculate short-term flicker severity, Pst, in power systems. EMD is a new signal processing method used for the analysis of nonlinear and nonstationary signals. Pst is an important quantity in the electric power quality index defined by the International Electrotechnical Commission. In the suggested approach, the voltage signal is separated into intrinsic mode function components using EMD. These components are used for calculating the voltage flicker amplitude and frequency, and Pst is calculated as a result of the statistical evaluation of flicker amplitude. EMD …


Upper Limb Rehabilitation Robot For Physical Therapy: Design, Control, And Testing, Erhan Akdoğan Jan 2016

Upper Limb Rehabilitation Robot For Physical Therapy: Design, Control, And Testing, Erhan Akdoğan

Turkish Journal of Electrical Engineering and Computer Sciences

In recent years, the treatment process of patients and disabled people who need rehabilitation and physical medicine has become more effective with the use of new devices and developing technology. The rehabilitation robot is one of the most important developments in new technology. The right therapeutic exercises and the objectivity of the evaluation of the range of motion (ROM; generated torque and muscular activation measurement of the patient) are extremely important factors during treatment. In this study, a lower limb rehabilitation robot was modified and controlled for upper limbs. The retrofitted robot system is able to do passive, active, and …


Square Root Central Difference-Based Fastslam Approach Improved By Differential Evolution, Haydar Ankişhan, Fi̇kret Ari, Emre Öner Tartan, Ahmet Güngör Pakfi̇li̇z Jan 2016

Square Root Central Difference-Based Fastslam Approach Improved By Differential Evolution, Haydar Ankişhan, Fi̇kret Ari, Emre Öner Tartan, Ahmet Güngör Pakfi̇li̇z

Turkish Journal of Electrical Engineering and Computer Sciences

This study presents a new approach to improve the performance of FastSLAM. The aim of the study is to obtain a more robust algorithm for FastSLAM applications by using a Kalman filter that uses Stirling's polynomial interpolation formula. In this paper, some new improvements have been proposed; the first approach is the square root central difference Kalman filter-based FastSLAM, called SRCD-FastSLAM. In this method, autonomous vehicle (or robot) position, landmarks' position estimations, and importance weight calculations of the particle filter are provided by the SRCD-Kalman filter. The second approach is an improved version of the SRCD-FastSLAM in which particles are …


An Analytical Formulation With Ill-Conditioned Numerical Scheme And Its Remedy: Scattering By Two Circular Impedance Cylinders, Emrah Sever, Fati̇h Di̇kmen, Olga Alexandrovna Suvorova, Yury Alexanderovich Tuchkin Jan 2016

An Analytical Formulation With Ill-Conditioned Numerical Scheme And Its Remedy: Scattering By Two Circular Impedance Cylinders, Emrah Sever, Fati̇h Di̇kmen, Olga Alexandrovna Suvorova, Yury Alexanderovich Tuchkin

Turkish Journal of Electrical Engineering and Computer Sciences

The regularization of the well-known analytical formulation of the monochromatic electromagnetic wave scattering problem from a syvstem with two neighbor impedance circular cylinders is presented. It is the improvement and extension of the work done for scattering from two perfectly conducting circular cylinders. Numerical results show that it is numerically much safer to solve the obtained infinite algebraic system at a lower truncation number also by ensuring the reliability of the solution.


On Scalable Rdfs Reasoning Using A Hybrid Approach, Tuğba Külahcioğlu, Hasan Bulut Jan 2016

On Scalable Rdfs Reasoning Using A Hybrid Approach, Tuğba Külahcioğlu, Hasan Bulut

Turkish Journal of Electrical Engineering and Computer Sciences

Reasoning is a vital ability for semantic web applications since they aim to understand and interpret the data on the World Wide Web. However, reasoning of large data sets is one of the challenges facing semantic web applications. In this paper, we present new approaches for scalable Resource Description Framework Schema (RDFS) reasoning. Our RDFS specific term-based partitioning algorithm determines required schema elements for each data partition while eliminating the data partitions that will not produce any inferences. With the two-level partitioning approach, we are able to carry out reasoning with limited resources. In our hybrid approach, we integrate two …


Ray Tracing Technique For Shaping A Dual Reflector Antenna System, Md Rezwanul Ahsan, Mohammad Tariqul Islam, Yoshihide Yamada, Norbahiah Misran Jan 2016

Ray Tracing Technique For Shaping A Dual Reflector Antenna System, Md Rezwanul Ahsan, Mohammad Tariqul Islam, Yoshihide Yamada, Norbahiah Misran

Turkish Journal of Electrical Engineering and Computer Sciences

In radio astronomy applications, antennas having the highest aperture efficiencies are requested. In order to meet this request, a reflector shaping program for dual reflector antennas has been developed. The design procedure is based on the geometrical optics where differential equations have been formulated to define the ray trace of the antenna system. Recently, the fourth generation programming language MATLAB has become well known for its numerical computing environment and very useful three-dimensional data visualization functions. The authors wished to make a dual reflector shaping program by a ray tracing method in MATLAB. In this paper, details of the program …


How To Categorize Emotional Speech Signals With Respect To The Speaker's Degree Of Emotional Intensity, Salman Karimi, Mohammad Hossein Sedaaghi Jan 2016

How To Categorize Emotional Speech Signals With Respect To The Speaker's Degree Of Emotional Intensity, Salman Karimi, Mohammad Hossein Sedaaghi

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, classifying different emotional content of speech signals automatically has become one of the most important comprehensive inquiries. The main subject in this field is related to the improvement of the correct classification rate (CCR) resulting from the proposed techniques. However, a literature review shows that there is no notable research on finding appropriate parameters that are related to the intensity of emotions. In this article, we investigate the proper features to be employed in the recognition of emotional speech utterances according to their intensities. In this manner, 4 emotional classes of the Berlin Emotional Speech database, happiness, anger, fear, …


Reconstructive Sensing Circuit For Complementary Resistive Switches-Based Crossbar Memories, Ertuğrul Karakulak, Reşat Mutlu, Erdem Uçar Jan 2016

Reconstructive Sensing Circuit For Complementary Resistive Switches-Based Crossbar Memories, Ertuğrul Karakulak, Reşat Mutlu, Erdem Uçar

Turkish Journal of Electrical Engineering and Computer Sciences

Complementary resistive switches (CRSs) are suggested as an alternative to one-cell memristor memories to decrease leakage currents. However, their sensing is more difficult and complex than one-cell memristor memories. A method has been given for sensing their state using only DC voltages in the literature. However, in this strategy, sensing one of the logic states results in the destruction of the state and the destroyed state must be written again. To the best of our knowledge, a circuit with this sensing strategy does not exist in the literature yet. In this paper, such a circuit employing this method, which is …


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.