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Full-Text Articles in Physical Sciences and Mathematics

Relay Coordination Analysis And Protection Solutions For Smart Grid Distribution Systems, Mehmet Tan Turan, Erdi̇n Gökalp Jan 2016

Relay Coordination Analysis And Protection Solutions For Smart Grid Distribution Systems, Mehmet Tan Turan, Erdi̇n Gökalp

Turkish Journal of Electrical Engineering and Computer Sciences

Growing complexity of conventional power grids and their management, increasing power demand and energy quality expectations considering grid reliability, and efficiency and security concerns have triggered the evolution of smart grids. This is an expected result of implementing new technologies in existing grids, including renewable sources such as wind turbines and photovoltaic modules. With implementation of such new elements to the system, the protection concept should be considered by system regulators. In order to analyze protection problems, simulation-based analysis should be carried out before high-cost experimental studies. In this study, a simulation-based evaluation for a smart grid-based distribution system is …


Economic Assessment Of A Hybrid Turboexpander-Fuel Cell Gas Energy Extraction Plant, Ahmad Darabi, Ahmad Shariati, Reza Ghanaee, Ali Soleimani Jan 2016

Economic Assessment Of A Hybrid Turboexpander-Fuel Cell Gas Energy Extraction Plant, Ahmad Darabi, Ahmad Shariati, Reza Ghanaee, Ali Soleimani

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a hybrid turboexpander-fuel cell (TE-FC) is investigated for extraction of electrical energy from high pressure gas in which the fuel cells are used for preheating the gas. Combination of expanders and fuel cells will reduce the fuel consumption and greenhouse gas emission. This study reveals that there are some circumstances in which the use of fuel cells in conjunction with a turboexpander is not recommended from an economic point of view. This paper seeks the region in which utilization of fuel cells along with a turboexpander presents maximum economic profit. Using the strategy provided in this paper …


Feature Selection For Movie Recommendation, Zehra Çataltepe, Mahi̇ye Uluyağmur, Esengül Tayfur Jan 2016

Feature Selection For Movie Recommendation, Zehra Çataltepe, Mahi̇ye Uluyağmur, Esengül Tayfur

Turkish Journal of Electrical Engineering and Computer Sciences

TV users have an abundance of different movies they could choose from, and with the quantity and quality of data available both on user behavior and content, better recommenders are possible. In this paper, we evaluate and combine different content-based and collaborative recommendation methods for a Turkish movie recommendation system. Our recommendation methods can make use of user behavior, different types of content features, and other users' behavior to predict movie ratings. We gather different types of data on movies, such as the description, actors, directors, year, and genre. We use natural language processing methods to convert the Turkish movie …


A Mapreduce-Based Distributed Svm Algorithm For Binary Classification, Ferhat Özgür Çatak, Mehmet Erdal Balaban Jan 2016

A Mapreduce-Based Distributed Svm Algorithm For Binary Classification, Ferhat Özgür Çatak, Mehmet Erdal Balaban

Turkish Journal of Electrical Engineering and Computer Sciences

Although the support vector machine (SVM) algorithm has a high generalization property for classifying unseen examples after the training phase~and a small loss value, the algorithm is not suitable for real-life classification and regression problems. SVMs cannot solve hundreds of thousands of examples in a training dataset. In previous studies on distributed machine-learning algorithms, the SVM was trained in a costly and preconfigured computer environment. In this research, we present a MapReduce-based distributed parallel SVM training algorithm for binary classification problems. This work shows how to distribute optimization problems over cloud computing systems with the MapReduce technique. In the second …


Modeling And Control Of A Doubly Fed Induction Generator With A Disturbance Observer: A Stator Voltage Oriented Approach, Eşref Emre Özsoy, Edin Golubovic, Asif Sabanovic, Seta Bogosyan, Meti̇n Gökaşan Jan 2016

Modeling And Control Of A Doubly Fed Induction Generator With A Disturbance Observer: A Stator Voltage Oriented Approach, Eşref Emre Özsoy, Edin Golubovic, Asif Sabanovic, Seta Bogosyan, Meti̇n Gökaşan

Turkish Journal of Electrical Engineering and Computer Sciences

The popularity of renewable energy conversion systems, and especially of wind energy, has been growing in recent years. Doubly fed induction generator (DFIG)-based wind energy systems are extensively used due to their wide range of active and reactive power controllability. Conventional DFIG control structures consist of decoupled PI rotor current controllers with stator flux orientation and machine parameter-dependent compensating terms. The accuracy of stator flux calculations is dependent on how accurately the stator resistance is known. Integration problems also exist and additional low-pass filters are implemented to accurately calculate the stator flux. In the current study, machine-dependent compensating terms are …


An Unsupervised Heterogeneous Log-Based Framework For Anomaly Detection, Asif Iqbal Hajamydeen, Nur Izura Udzir, Ramlan Mahmod, Abdul Azim Abdul Ghani Jan 2016

An Unsupervised Heterogeneous Log-Based Framework For Anomaly Detection, Asif Iqbal Hajamydeen, Nur Izura Udzir, Ramlan Mahmod, Abdul Azim Abdul Ghani

Turkish Journal of Electrical Engineering and Computer Sciences

Log analysis is a method to identify intrusions at the host or network level by scrutinizing the log events recorded by the operating systems, applications, and devices. Most work contemplates a single type of log for analysis, leading to an unclear picture of the situation and difficulty in deciding the existence of an intrusion. Moreover, most existing detection methods are knowledge-dependent, i.e. using either the characteristics of an anomaly or the baseline of normal traffic behavior, which limits the detection process to only anomalies based on the acquired knowledge. To discover a wide range of anomalies by scrutinizing various logs, …


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 …


An Intelligent Design Optimization Of A Permanent Magnet Synchronous Motor By Artificial Bee Colony Algorithm, Mümtaz Mutluer, Osman Bi̇lgi̇n Jan 2016

An Intelligent Design Optimization Of A Permanent Magnet Synchronous Motor By Artificial Bee Colony Algorithm, Mümtaz Mutluer, Osman Bi̇lgi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

The artificial bee colony algorithm is one of the latest stochastic methods based on swarm intelligence. The algorithm simulates the foraging behavior of honeybees. The structure of the algorithm is quite simple and its coding is very easy. This paper proposes a design optimization based on geometrical variables to obtain a highly efficient surface-mounted permanent magnet synchronous motor with concentrated winding by use of the artificial bee colony algorithm. Input parameters for the algorithm are the geometrical variables of the motor. This approach is more advantageous than finite element analysis requiring a long period of time. Results of the artificial …


Finger-Vein Biometric Identification Using Convolutional Neural Network, Syafeeza Ahmad Radzi, Mohamed Khalil Hani, Rabia Bakhteri Jan 2016

Finger-Vein Biometric Identification Using Convolutional Neural Network, Syafeeza Ahmad Radzi, Mohamed Khalil Hani, Rabia Bakhteri

Turkish Journal of Electrical Engineering and Computer Sciences

A novel approach using a convolutional neural network (CNN) for finger-vein biometric identification is presented in this paper. Unlike existing biometric techniques such as fingerprint and face, vein patterns are inside the body, making them virtually impossible to replicate. This also makes finger-vein biometrics a more secure alternative without being susceptible to forgery, damage, or change with time. In conventional finger-vein recognition methods, complex image processing is required to remove noise and extract and enhance the features before the image classification can be performed in order to achieve high performance accuracy. In this regard, a significant advantage of the CNN …


Modeling And Rotor Field-Oriented Control Of A Faulty Three-Phase Induction Motor Based On Gsa For Tuning Of Pi Controllers, Ali Monadi, Mohammad Jannati, Nik Rumizi Nik Idris, Ahmad Athif Mohd Faudzi, Frede Blaabjerg Jan 2016

Modeling And Rotor Field-Oriented Control Of A Faulty Three-Phase Induction Motor Based On Gsa For Tuning Of Pi Controllers, Ali Monadi, Mohammad Jannati, Nik Rumizi Nik Idris, Ahmad Athif Mohd Faudzi, Frede Blaabjerg

Turkish Journal of Electrical Engineering and Computer Sciences

modeling and a rotor field-oriented control (RFOC) system for controlling a faulty three-phase induction motor (three-phase IM when one of the phases is disconnected). In the adapted scheme for controlling the faulty IM, it is necessary for the PI controller coefficients to change. For this purpose, the gravitational search algorithm (GSA) is used for tuning of PI controllers. The results show the strength and ability of the technique to improve the performance of the faulty IM control.


Modeling And Control Of A 6-Control-Area Interconnected Power System To Protect The Network Frequency Applying Different Controllers, Ngockhoat Nguyen, Qi Huang, Thi-Mai-Phuong Dao Jan 2016

Modeling And Control Of A 6-Control-Area Interconnected Power System To Protect The Network Frequency Applying Different Controllers, Ngockhoat Nguyen, Qi Huang, Thi-Mai-Phuong Dao

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we first analyze and build a model of the 6-control-area interconnected power system as the typical case study. Subsequently, different frequency controllers based on tie-line bias control strategy, namely integral, proportional--integral, proportional--integral--derivative, and PI-based fuzzy logic, will be investigated and applied to the power system model. The most important control performances, such as overshoots and settling times, are considered in this study to evaluate the stability of the power system and choose the most suitable controller for maintaining the network frequency. The simulation results have been achieved by using MATLAB/Simulink package version 2013 in this work. According …


Theoretical Analysis Of Doping Management And Its Effects On Power Scaling, Ami̇ra Tandi̇rovi̇ç Gürsel, Parvi̇z Elahi̇, Fati̇h Ömer İlday, Mustafa Sadetti̇n Özyazici Jan 2016

Theoretical Analysis Of Doping Management And Its Effects On Power Scaling, Ami̇ra Tandi̇rovi̇ç Gürsel, Parvi̇z Elahi̇, Fati̇h Ömer İlday, Mustafa Sadetti̇n Özyazici

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Automated Separation Of Gray And White Matter In Brain Mris By Fastened Segments Of Geodesic Contours, Ali̇ İskurt Jan 2016

Automated Separation Of Gray And White Matter In Brain Mris By Fastened Segments Of Geodesic Contours, Ali̇ İskurt

Turkish Journal of Electrical Engineering and Computer Sciences

tissues in the brain separated by an interface. Extraction of this boundary is very important for quantitative analysis and monitoring of atrophy. A perfect capture for this purpose is a missing vital item for which research continues. In order to get close to such precision, two novel systems are presented for segmentation of cortical GM and WM in brain MRIs. The system imitates human perceptual sensitiveness to contrast, which is the basic principle of edge detection algorithms, and completes its shortcoming feature of segmentation. As well as being completely automatic, the system is also unsupervised. The correct GM-WM boundary rate …


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 …


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 …


Relay Sliding Mode Control Based On The Input-Output Model, Şölen Kumbay Yildiz, Hüseyi̇n Demi̇rci̇oğlu Jan 2016

Relay Sliding Mode Control Based On The Input-Output Model, Şölen Kumbay Yildiz, Hüseyi̇n Demi̇rci̇oğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the relay sliding mode control method based on the input-output model proposed in previous studies is revisited. Sliding conditions under ideal operating conditions are reformulated to fortify the theoretical background. Some additional issues, namely the effects of disturbances and measurement noise on the sliding mode conditions, are addressed and analyzed in detail. Finally, the theoretical results are put to the test by detailed simulation examples.


Design Of A Low-Power, Low-Cost Uhf Rfid Reader Module, Özgür Bostan, Hüseyi̇n Ulvi̇ Aydoğmuş, Serkan Topaloğlu Jan 2016

Design Of A Low-Power, Low-Cost Uhf Rfid Reader Module, Özgür Bostan, Hüseyi̇n Ulvi̇ Aydoğmuş, Serkan Topaloğlu

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


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 …


Stereo And Kinectfusion For Continuous 3d Reconstruction And Visual Odometry, Özgür Yilmaz, Fati̇h Karakuş Jan 2016

Stereo And Kinectfusion For Continuous 3d Reconstruction And Visual Odometry, Özgür Yilmaz, Fati̇h Karakuş

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Design Of Compact Octagonal Slotted Hexagonal And Rectangular Shaped Monopole Antennas For Dual/Uwb Applications, Praveen Naidu Vummadisetty, Raj Kumar Jan 2016

Design Of Compact Octagonal Slotted Hexagonal And Rectangular Shaped Monopole Antennas For Dual/Uwb Applications, Praveen Naidu Vummadisetty, Raj Kumar

Turkish Journal of Electrical Engineering and Computer Sciences

applications are proposed in this paper. In both antennas, the slot in the ground plane is of octagonal shape, while the patch is rectangular in one of the antennas and hexagonal in the other. Thin metallic stubs of different lengths are added to the ground plane and protrude into the slot. These stubs help to improve the impedance matching over a broader bandwidth. The antennas are very compact in size and designed on low-cost FR4 substrate. The measured impedance bandwidths (S$_{11}


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.


A Novel Approach For Automatic Blood Vessel Extraction In Retinal Images: Complex Ripplet-I Transform And Complex Valued Artificial Neural Network, Murat Ceylan, Hüseyi̇n Yaşar Jan 2016

A Novel Approach For Automatic Blood Vessel Extraction In Retinal Images: Complex Ripplet-I Transform And Complex Valued Artificial Neural Network, Murat Ceylan, Hüseyi̇n Yaşar

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Threshold Optimization According To The Restricted Bayes Criterion In Decentralized Detection Problems, Suat Bayram, Hakan Soku Jan 2016

Threshold Optimization According To The Restricted Bayes Criterion In Decentralized Detection Problems, Suat Bayram, Hakan Soku

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.


Parametric-Based Mobility For Providing Opportunistic Geocasting In Spatially Separated Wireless Sensor Networks, Selvi Ravindran, Narayanasamy Palanisamy, Vetriselvi Vetrian Jan 2016

Parametric-Based Mobility For Providing Opportunistic Geocasting In Spatially Separated Wireless Sensor Networks, Selvi Ravindran, Narayanasamy Palanisamy, Vetriselvi Vetrian

Turkish Journal of Electrical Engineering and Computer Sciences

Uneven deployment and environment constraint leads to the formation of a spatially separated wireless sensor network (SS-WSN). Most of the traditional WSN architectures consist of static nodes that are densely deployed over a sensing area and are fully connected. SS-WSN is a group of disjoint subnetworks where connectivity is generally maintained by energy rich mobile nodes (ERMN), which roam about from one subnetwork to another. We propose an algorithm whereby the mobility of ERMN helps in distributing the geo message opportunistically in the region of interest. The routing consists of two phases: (1) transmission of the geo message from the …


Comparative Study Of Drive Systems Using Vector-Controlled Pmsm Fed By A Matrix Converter And A Conventional Frequency Converter, Pawel Szczesniak, Konrad Urbanski, Zbigniew Fedyczak, Krzysztof Zawirski Jan 2016

Comparative Study Of Drive Systems Using Vector-Controlled Pmsm Fed By A Matrix Converter And A Conventional Frequency Converter, Pawel Szczesniak, Konrad Urbanski, Zbigniew Fedyczak, Krzysztof Zawirski

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a comparative study of a drive system with a permanent magnet synchronous motor fed by a matrix converter and a voltage source inverter with diode rectifier stage. A rotor-oriented vector control is implemented in the drive control. Space vector modulation techniques are used for both converters in the output current modulation process. Initial simulation test results and comparison are presented. The advantages of both solutions are indicated. Special attention is given to the drive control in the low speed range. The main aim of this article is to present drive systems with a matrix converter as an …


Behavior Learning Of A Memristor-Based Chaotic Circuit By Extreme Learning Machines, Ayşegül Uçar, Emrehan Yavşan Jan 2016

Behavior Learning Of A Memristor-Based Chaotic Circuit By Extreme Learning Machines, Ayşegül Uçar, Emrehan Yavşan

Turkish Journal of Electrical Engineering and Computer Sciences

As the behavior of a chaotic Chua's circuit is nonstationary and inherently noisy, it is regarded as one of the most challenging applications. One of the fundamental problems in the prediction of the behavior of a chaotic Chua's circuit is to model the circuit with high accuracy. The current paper presents a novel method based on multiple extreme learning machine (ELM) models to learn the chaotic behavior of the four elements canonical Chua's circuit containing a memristor instead of a nonlinear resistor only by using the state variables as the input. In the proposed method four ELM models are used …


A Comprehensive Comparison Of Features And Embedding Methods For Face Recognition, Hasan Serhan Yavuz, Hakan Çevi̇kalp, Ri̇fat Edi̇zkan Jan 2016

A Comprehensive Comparison Of Features And Embedding Methods For Face Recognition, Hasan Serhan Yavuz, Hakan Çevi̇kalp, Ri̇fat Edi̇zkan

Turkish Journal of Electrical Engineering and Computer Sciences

Face recognition is an essential issue in modern-day applications since it can be used in many areas for several purposes. Many methods have been proposed for face recognition. It is a difficult task since variations in lighting, instantaneous mimic varieties, posing angles, and scaling differences can drastically change the appearance of the face. To suppress these complications, effective feature extraction and proper alignment of face images gain as much importance as the recognition method choice. In this paper, we provide an extensive comparison of the state-of-the-art face recognition methods with the most well-known techniques used in feature representation. In order …


Grid-Connected Induction Generator Interturn Fault Analysis Using A Pca-Ann-Based Algorithm, Haydar Bayar, Ümi̇t Kemaletti̇n Terzi̇ Jan 2016

Grid-Connected Induction Generator Interturn Fault Analysis Using A Pca-Ann-Based Algorithm, Haydar Bayar, Ümi̇t Kemaletti̇n Terzi̇

Turkish Journal of Electrical Engineering and Computer Sciences

It is difficult for short circuits among the internal windings of one phase in electrical machines to be determined in a reliable and speedy manner. The failure currents that occur, especially in short circuits with a few windings, are at such low levels that they cannot be determined by relay systems. This results in growing faults and damage. In this study, we designed a model that can define winding failures successfully at very small levels by using the PCA and ANN algorithms. We tested the real-time faults and measured the system performance with the installed test rig. The developed protection …


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 …