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A Complete Motor Protection Algorithm Based On Pca And Ann: A Real Time Study, OKAN ÖZGÖNENEL, TURGAY YALÇIN 2011 TÜBİTAK

A Complete Motor Protection Algorithm Based On Pca And Ann: A Real Time Study, Okan Özgönenel, Turgay Yalçin

Turkish Journal of Electrical Engineering and Computer Sciences

Protection of an induction motor (IM) against possible faults, such as a stator winding fault, due to thermal deterioration, rotor bar and bearing failures, is very important in environments in which it is used intensively, as in industry as an actuator. In this work, a real time digital protection algorithm based on principal component analysis (PCA) and neural network method is presented for induction motors. The proposed protection algorithm covers internal winding faults (also known as stator faults), broken rotor bar faults, and bearing faults. Many laboratory experiments have been performed on a specially designed induction motor to evaluate the …


Remote Mutual Authentication And Key Agreement Scheme Based On Elliptic Curve Cryptosystem, EUNJUN YOON 2011 TÜBİTAK

Remote Mutual Authentication And Key Agreement Scheme Based On Elliptic Curve Cryptosystem, Eunjun Yoon

Turkish Journal of Electrical Engineering and Computer Sciences

Remote mutual authentication is an important part of security, along with confidentiality and integrity, for systems that allow remote access over untrustworthy networks, like the Internet. In 2006, Shieh-Wang pointed out the weakness of Juang's remote mutual authentication scheme using smart card and further proposed a novel remote user authentication scheme using smart card. However, this paper demonstrates that Shieh-Wang's scheme still does not provide perfect forward secrecy and is vulnerable to a privileged insider's attack. We also present an improved scheme based on the Elliptic Curve Diffie-Hellman problem (ECDHP) and secure one-way hash function, in order to isolate such …


Fully Integrated Universal Biquads Using Operational Transresistance Amplifiers With Mos-C Realization, AHMET GÖKÇEN, SELÇUK KILINÇ, UĞUR ÇAM 2011 TÜBİTAK

Fully Integrated Universal Biquads Using Operational Transresistance Amplifiers With Mos-C Realization, Ahmet Gökçen, Selçuk Kilinç, Uğur Çam

Turkish Journal of Electrical Engineering and Computer Sciences

Universal biquadratic filters employing operational transresistance amplifiers are presented. All 5 different second-order filtering functions, namely low-pass, high-pass, band-pass, notch, and all-pass, can be realized. The quality factor of the filters can be adjusted electronically without affecting resonant frequency. The configuration can be made fully integrated based on MOS-C realization, by making use of the current differencing and internally grounded inputs of OTRA. PSpice simulation results are given to verify the theoretical analysis.


Online Speed Control Of A Brushless Ac Servomotor Based On Artificial Neural Networks, SİBEL PARTAL, İBRAHİM ŞENOL, AHMET FARUK BAKAN, KAMURAN NUR BEKİROĞLU 2011 TÜBİTAK

Online Speed Control Of A Brushless Ac Servomotor Based On Artificial Neural Networks, Si̇bel Partal, İbrahi̇m Şenol, Ahmet Faruk Bakan, Kamuran Nur Beki̇roğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an alternative approach to speed estimation of brushless AC servomotors is presented. Speed control is realized in the following steps. First, the servomotor was mathematically modelled; the driver system was designed and speed control of the servomotor was accomplished with feedback. Next, a network structure representing the electrical and mechanical properties of the servomotor was built via Artificial Neural Network (ANN) and trained with the results of the first step. The weights obtained from the neural nwork training were inserted into the control algorithm in accordance with the ANN. Finally, speed estimation was achieved based on the …


Electromagnetic Scattering From Layered Strip Geometries: The Method Of Moments Study With The Sinc Basis, TANER OĞUZER, FADIL KUYUCUOĞLU, İBRAHİM AVGIN 2011 TÜBİTAK

Electromagnetic Scattering From Layered Strip Geometries: The Method Of Moments Study With The Sinc Basis, Taner Oğuzer, Fadil Kuyucuoğlu, İbrahi̇m Avgin

Turkish Journal of Electrical Engineering and Computer Sciences

Electromagnetic scattering from strips of layers is analyzed using the method of moments (MoM) for both polarizations in spatial domain with the sinc-type orthogonal sets as basis and testing functions. We exploited the sinc function's properties of exponential convergence, the orthogonality, easy convolution and better handling of singular kernels in MoM procedure resulting in fast performance and reasonable accuracy even in ordinary MoM treatment. We transferred the integral of the Hankel function multiplied by sinc functions to Hankel function introducing a slight error with large band width. We proved that this relative error during the generation of the main matrix …


An Effective Real Coded Ga Based Fuzzy Controller For Speed Control Of A Bldc Motor Without Speed Sensor, ÖMER AYDOĞDU, RAMAZAN AKKAYA 2011 TÜBİTAK

An Effective Real Coded Ga Based Fuzzy Controller For Speed Control Of A Bldc Motor Without Speed Sensor, Ömer Aydoğdu, Ramazan Akkaya

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, an effective Real Coded Genetic Algorithm (GA) based optimal fuzzy controller is proposed. The fuzzy controller is used for sensorless speed control of a Brushless DC (BLDC) motor in DSP based application system. The advantages of adopting a real coded GA for the design and optimization of fuzzy controllers, which have a great deal of design and optimization parameters, are analyzed. Having accomplished optimization of developed fuzzy control system, a multi-objective performance index has been defined and it has been used as an objective function to be minimized in the real coded GA. Thus, the system can …


Low-Complexity Parameters Estimator For Multiple 2d Domain Incoherently Distributed Sources, XIANSHENG GUO, QUN WAN, XIAOFENG SHEN, HENG DOU 2011 TÜBİTAK

Low-Complexity Parameters Estimator For Multiple 2d Domain Incoherently Distributed Sources, Xiansheng Guo, Qun Wan, Xiaofeng Shen, Heng Dou

Turkish Journal of Electrical Engineering and Computer Sciences

A new low-complexity parameters estimator for multiple two-dimensional (2D) domain incoherently distributed (ID) sources is presented. One 2D domain ID source is parameterized with four parameters, the central azimuth direction-of-arrival (DOA), azimuth angular spread, central elevation DOA and elevation angular spread. Based on the eigenstructure between the steering matrix and signal subspace, an average total least-squares via rotational invariance technique (TLS-ESPRIT) is used to estimate the central elevation DOA, and then a generalized multiple signal classification (GMUSIC) algorithm is derived to estimate the central azimuth DOA. Utilizing preliminary estimates obtained at a pre-processing stage, the angular spread parameters can be …


Rate 1 Space-Time And Space-Frequency Spreading Diversity Technique, GÖKÇE HACIOĞLU, ALİ GANGAL 2011 TÜBİTAK

Rate 1 Space-Time And Space-Frequency Spreading Diversity Technique, Gökçe Hacioğlu, Ali̇ Gangal

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a rate 1 transmitter diversity technique is proposed. The proposed technique uses spreading transform and space-time block coding (STBC) together. Space-time, space-frequency, and frequency diversity applications of the proposed technique are shown. The code matrix of the proposed technique can be designed systematically. The proposed technique needs the channel coefficients to stay constant over transmission of 2 rows of the coding matrix regardless of the size of the coding matrix or the diversity order. However, joint detection of the symbols is required for the proposed technique. We used computer simulations to compare our technique with the quasi-orthogonal …


On The Existence Of Common Lyapunov Functions For Consensus Algorithms Based On Averaging, MEHMET AKAR, ROBERT SHORTEN 2011 TÜBİTAK

On The Existence Of Common Lyapunov Functions For Consensus Algorithms Based On Averaging, Mehmet Akar, Robert Shorten

Turkish Journal of Electrical Engineering and Computer Sciences

This paper addresses distributed deterministic consensus algorithms based on averaging. We relate the conditions for achieving consensus to the existence of a common norm for a set of row-stochastic matrices associated with the original set of averaging matrices. For a system to achieve consensus, it is shown that this associated set of matrices should have a Common Lyapunov Function, even if the original set might not have one.


Ecg Denoising On Bivariate Shrinkage Function Exploiting Interscale Dependency Of Wavelet Coefficients, SEMA KAYHAN, ERGUN ERÇELEBİ 2011 TÜBİTAK

Ecg Denoising On Bivariate Shrinkage Function Exploiting Interscale Dependency Of Wavelet Coefficients, Sema Kayhan, Ergun Erçelebi̇

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new method for electrocardiogram (ECG) denoising based on bivariate shrinkage functions exploiting the interscale dependency of wavelet coefficients. Most nonlinear thresholding methods based on wavelet transform denoising assume that the wavelet coefficients are independent. However, wavelet coefficients of ECG signals have significant dependencies. In this paper, we proposed a new method by considering the dependencies between the coefficients and their parents in detail on a bivariate shrinkage function for denoising of an ECG signal corrupted by different types of noises, such as muscle artifact noise, electrode motion, and white noise. In real-time applications, reduction of computational …


Decentralized Robust Load-Frequency Control Of Power System Based On Quantitative Feedback Theory, AIDIN SAKHAVATI, GEVORK GHAREHPETIAN, SEYED HOSSEIN HOSSEINI 2011 TÜBİTAK

Decentralized Robust Load-Frequency Control Of Power System Based On Quantitative Feedback Theory, Aidin Sakhavati, Gevork Gharehpetian, Seyed Hossein Hosseini

Turkish Journal of Electrical Engineering and Computer Sciences

This paper aims at investigating the problem of Load Frequency Control (LFC) in interconnected power systems in order to obtain robustness against uncertainties. A design method for a robust controller, based on Quantitative Feedback Theory (QFT), has been presented in this paper. For a two-area power system, the simulation results show that the system response with the proposed QFT controller exhibits transient response beyond PI controllers. It is also shown that the transient response of the tie line power can also be improved.


Sliding Mode Controller Gain Adaptation And Chattering Reduction Techniques For Dsp-Based Pm Dc Motor Drives, MEHMET DAL, REMUS TEODORESCU 2011 TÜBİTAK

Sliding Mode Controller Gain Adaptation And Chattering Reduction Techniques For Dsp-Based Pm Dc Motor Drives, Mehmet Dal, Remus Teodorescu

Turkish Journal of Electrical Engineering and Computer Sciences

In order to achieve and maintain the prospective benefits of sliding mode control (SMC) methodology, the phenomenon known as ``chattering'', the main obstacle encountered in real-time applications, has to be suppressed. In this study, two promising switching control gain adaptation and chattering reduction techniques are investigated, and the effectiveness of chattering suppression for current regulation of PM DC drives is tested. The sampling rate was also examined to determine how it affects the amplitude of chattering. This paper concentrates on various combinations of observer-based methods in order to find the best solution for chattering reduction. To find a practical solution …


Minimization Of Load Shedding By Sequential Use Of Linear Programming And Particle Swarm Optimization, MEHRDAD TARAFDAR HAGH, SADJAD GALVANI 2011 TÜBİTAK

Minimization Of Load Shedding By Sequential Use Of Linear Programming And Particle Swarm Optimization, Mehrdad Tarafdar Hagh, Sadjad Galvani

Turkish Journal of Electrical Engineering and Computer Sciences

Minimization of load shedding during contingency conditions is solved as an optimization problem. As a new topic, instead of local load shedding, total load shedding of a large power system is considered. Power generation rescheduling is considered to minimize the load shedding, as well. Different importance factors for buses are also considered. The linear programming method (LP) is used to solve this problem in a short period of time without considering some power system constraints. Particle swarm optimization (PSO) is also used to solve the problem by considering all power system constraints, but with a longer solving time. Finally, a …


A Unified Series-Parallel Active Filter System For Nonperiodic Disturbances, MEHMET UÇAR, ŞULE ÖZDEMİR, ENGİN ÖZDEMİR 2011 TÜBİTAK

A Unified Series-Parallel Active Filter System For Nonperiodic Disturbances, Mehmet Uçar, Şule Özdemi̇r, Engi̇n Özdemi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a 3-phase, 4-wire unified series-parallel active filter (USPAF) system for periodic and nonperiodic disturbance compensation using a generalized nonactive power theory. The USPAF system consists of a series active filter (AF), parallel AF, and split DC-link capacitors with the midpoint of the DC-link connected to the neutral wire. The generalized nonactive power theory is applicable to single-phase or multiphase, sinusoidal or nonsinusoidal, periodic or nonperiodic, and balanced or unbalanced electrical systems. The theory was implemented previously in a parallel AF. In this study, the USPAF system is proposed to compensate for the nonsinusoidal and nonperiodic currents and …


Measuring Traffic Flow And Classifying Vehicle Types: A Surveillance Video Based Approach, ERHAN İNCE 2011 TÜBİTAK

Measuring Traffic Flow And Classifying Vehicle Types: A Surveillance Video Based Approach, Erhan İnce

Turkish Journal of Electrical Engineering and Computer Sciences

The paper presents a vehicle counting method based on invariant moments and shadow aware foreground masks. Estimation of the background and the segmentation of foreground regions can be done using either the Mixture of Gaussians model (MoG) or an improved version of the Group Based Histogram (GBH) technique. The work demonstrates that, even though the improved GBH method delivers performance just as good as MoG, considering computational efficiency, MoG is more suitable. Shadow aware binary masks for each frame are formed by using background subtraction and shadow removal in the Hue Saturation and Value (HSV) domain. To determine new vehicles …


Applying The Finite Element Method To Analyze Predischarge Lightning Rods, CHIN-TSUNG HSIEH, MENG-HUI WANG, Cho-Yu Pan 2011 TÜBİTAK

Applying The Finite Element Method To Analyze Predischarge Lightning Rods, Chin-Tsung Hsieh, Meng-Hui Wang, Cho-Yu Pan

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the finite element method is applied for analyzing 4 types of lightning rods in order to select the optimal lightning rod configuration. First, software is used to calculate the 2D protective coverage of different lighting rods, and 4 kinds of typical lightning rods are simulated in different conditions. The analyzed results are then applied for the selection of the optimal lighting rod and the frame of the lighting rod. The analyzed results would be useful for electrical engineers to design lightning rods that offer the most effective lighting protection; the simulated results are also useful for the …


A New, Improved Cmos Realization Of Cdta And Its Filter Applications, FIRAT KAÇAR, HULUSİ HAKAN KUNTMAN 2011 TÜBİTAK

A New, Improved Cmos Realization Of Cdta And Its Filter Applications, Firat Kaçar, Hulusi̇ Hakan Kuntman

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a high-performance current differencing transconductance amplifier (CDTA), a recently reported active element, especially suitable for analog signal processing applications. A high linearity CMOS configuration for a CDTA is made up of high linearity input and output stages. The proposed CDTA provides high output impedance at port X and excellent input/output current tracking. A biquad filter circuit was chosen as an application example in order to demonstrate the performance of the CDTA. PSpice simulation results using a TSMC 0.35-\mu m CMOS process model were included to verify the expected values.


Performance Evaluation Of Nonparametric Ica Algorithm For Fetal Ecg Extraction, YUSUF SEVİM, AYTEN ATASOY 2011 TÜBİTAK

Performance Evaluation Of Nonparametric Ica Algorithm For Fetal Ecg Extraction, Yusuf Sevi̇m, Ayten Atasoy

Turkish Journal of Electrical Engineering and Computer Sciences

Fetal electrocardiograms (FECG) contain important indications about the health and condition of the fetus. In this respect, it is crucial to apply a robust algorithm to ECG data for extraction of the FECG signal. Most of the independent component analysis (ICA) algorithms used for this purpose rely on simple statistical models. Such algorithms can fail to separate desired signals when the assumed statistical model is inaccurate. Statistical models can be estimated accurately using kernel density estimation methods. Therefore, the kernel density estimation method was used in this paper for building an ICA algorithm (nonparametric ICA: NpICA) and the algorithm was …


A Fuzzy Rule-Based System For Predicting The Live Weight Of Holstein Cows Whose Body Dimensions Were Determined By Image Analysis, ŞAKİR TAŞDEMİR, ABDULLAH ÜRKMEZ, ŞEREF İNAL 2011 TÜBİTAK

A Fuzzy Rule-Based System For Predicting The Live Weight Of Holstein Cows Whose Body Dimensions Were Determined By Image Analysis, Şaki̇r Taşdemi̇r, Abdullah Ürkmez, Şeref İnal

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this study was to determine the body measurement of Holstein cows through image analysis (IA) and to estimate their live weight (LW) by means of a fuzzy rule-based model using the body measurements. For this purpose, a photography environment was established at a dairy cattle farm where a large number of cows were kept. First, digital photographs of each animal were synchronously taken from different directions with Canon EOS 400D cameras. At the same time, body dimensions, namely wither height (WH), hip height (HH), body length (BL), and hip width (HW), of the cows were manually measured …


Fully Parallel Ann-Based Arrhythmia Classifier On A Single-Chip Fpga: Fpaac, AHMET TURAN ÖZDEMİR, KENAN DANIŞMAN 2011 TÜBİTAK

Fully Parallel Ann-Based Arrhythmia Classifier On A Single-Chip Fpga: Fpaac, Ahmet Turan Özdemi̇r, Kenan Danişman

Turkish Journal of Electrical Engineering and Computer Sciences

Recognition of cardiac arrhythmias by electrocardiogram (ECG) is an important issue for diagnosis of cardiac abnormalities. Many studies on recognition of cardiac arrhythmias by ECG, using various techniques, have been performed in the past 20 years. Artificial neural networks (ANNs) are the most widely used tool in medical diagnosis systems (MDS) because of their powerful prediction characteristics. An ANN model is inspired by real biological neural networks, with a parallel structure that is potentially fast for computation. However, the suggested ANN architectures in the literature can only be run sequentially, on powerful processors, due to their complexity. Our approach enables …


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