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Full-Text Articles in Engineering

A Reduced-Order Observer Based On Stator Flux Estimation With Straightforward Parameter Identification For Sensorless Control Of Dfigs, Rahim Ajabi Farshbaf, Mohammad Reza Azizian, Vahid Eslampanah Jan 2017

A Reduced-Order Observer Based On Stator Flux Estimation With Straightforward Parameter Identification For Sensorless Control Of Dfigs, Rahim Ajabi Farshbaf, Mohammad Reza Azizian, Vahid Eslampanah

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new reducer-order observer for sensorless control of doubly fed induction generators (DFIGs), based on the Luenberger algorithm. Stable operation of the suggested observer is also considered in the design guidelines. Stator flux is selected as the state variable for the observer and its estimation error is used to correct the observer operation. The gain matrix of the proposed observer is calculated on the basis of flux error dynamics. The adaptation mechanism of the proposed observer is selected based on an estimation of rotor currents. A proportional integrator (PI) block is used in the structure of the …


Robust Control For Line-Of-Sight Stabilization Of A Two-Axis Gimbal System, Mehmet Baskin, Mehmet Kemal Leblebi̇ci̇oğlu Jan 2017

Robust Control For Line-Of-Sight Stabilization Of A Two-Axis Gimbal System, Mehmet Baskin, Mehmet Kemal Leblebi̇ci̇oğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Line-of-sight stabilization against various disturbances is an essential property of gimbaled imaging systems mounted on mobile platforms. In recent years, the importance of target detection from higher distances has increased. This has raised the need for better stabilization performance. For that reason, stabilization loops are designed such that they have higher gains and larger bandwidths. As these are required for good disturbance attenuation, sufficient loop stability is also needed. However, model uncertainties around structural resonances impose strict restrictions on sufficient loop stability. Therefore, to satisfy high stabilization performance in the presence of model uncertainties, robust control methods are required. In …


Method Of Singular Integral Equations In Diffraction By Semi-Infinite Grating: $H$-Polarization Case, Mstislav Kaliberda, Leonid Lytvynenko, Sergey Pogarsky Jan 2017

Method Of Singular Integral Equations In Diffraction By Semi-Infinite Grating: $H$-Polarization Case, Mstislav Kaliberda, Leonid Lytvynenko, Sergey Pogarsky

Turkish Journal of Electrical Engineering and Computer Sciences

Diffraction of the $H$-polarized electromagnetic wave by a semi-infinite strip grating is considered. The scattered field is represented as a superposition of the field induced by the currents on the strips of an infinite periodic grating and the field induced by the correction current excited due to end of the grating. Singular integral equations with additional conditions for infinite and semi-infinite periodic gratings are obtained. The current on the strips and spectral function of scattered field are expressed in terms of the solution of these equations. Numerical results for the near and far fields distribution are represented.


A New Approach To Pulse Deinterleaving Based On Adaptive Thresholding, Mostafa Bagheri, Mohammad Hossein Sedaaghi Jan 2017

A New Approach To Pulse Deinterleaving Based On Adaptive Thresholding, Mostafa Bagheri, Mohammad Hossein Sedaaghi

Turkish Journal of Electrical Engineering and Computer Sciences

Since histogram-based methods are formed by some simple differences, they are very desirable for deinterleaving. However, their main imperfection concerns recognizing complex pulse repetition interval (PRI) patterns like jittered and staggered ones.In this paper, we present new thresholds to detect jittered and staggered PRI from histogram-based methods even in complex circumstances such as noisy time of arrival (TOA), complex PRI patterns, and large missing pulses. Simulation results demonstrate that our method can detect and extract constant, jittered, and staggered PRI correctly. Moreover, the method is proved to be considerably robust and reliable at a missing pulses rate up to 30%.


A High Performance Hysteresis Current Control Of A Permanent Magnet Synchronous Motor Drive, Cosmas Ogbuka, Cajethan Nwosu, Marcel Agu Jan 2017

A High Performance Hysteresis Current Control Of A Permanent Magnet Synchronous Motor Drive, Cosmas Ogbuka, Cajethan Nwosu, Marcel Agu

Turkish Journal of Electrical Engineering and Computer Sciences

A high performance hysteresis current control of a permanent magnet synchronous motor (PMSM) drive is developed in this paper. The core advantage of field orientation control (FOC) is utilized to separate the flux and torque control components of the stator current of the PMSM. Specifically, the objectives of this work are to develop and utilize the HCC algorithm for FOC of a complete closed-loop speed-controlled PMSM drive system, optimize the control algorithm to obtain fast speed response while maintaining effective current and torque tracking, and examine the hysteresis current control action clearly showing the inverter switching and the effects of …


Comparison Of Group Key Establishment Protocols, Serap Şahi̇n, Rabi̇a Aslanoğlu Jan 2017

Comparison Of Group Key Establishment Protocols, Serap Şahi̇n, Rabi̇a Aslanoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Recently group-oriented applications over unsecure open networks such as Internet or wireless networks have become very popular. Thus, group communication security over unsecure open networks has become a vital concern. Group key establishment (GKE) protocols are used to satisfy the confidentiality requirement of a newly started communication session by the generation or sharing of an ephemeral common key between the group members. In this study, we analyze the computation and communication efficiency of GKE protocols. Besides confidentiality, the security characteristics of identification and integrity control are also required for all steps of the protocol implementations. Thus, the main contribution of …


Robust Adaptive Fuzzy Control Of A Three-Phase Active Power Filter Based On Feedback Linearization, Shixi Hou, Juntao Fei Jan 2017

Robust Adaptive Fuzzy Control Of A Three-Phase Active Power Filter Based On Feedback Linearization, Shixi Hou, Juntao Fei

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a robust adaptive fuzzy control system using feedback linearization is proposed for a three-phase active power filter (APF). The APF system is divided into two separate loops: the current dynamic inner loop and the DC voltage dynamic outer loop. Adaptive fuzzy tracking control using feedback linearization is employed for the current dynamic inner loop to overcome the drawbacks of the conventional method. The proposed controller can ensure proper tracking of the reference current and impose desired dynamic behavior, giving robustness and insensitivity to parameter variations. Adaptive fuzzy proportional-integral control is applied to the DC voltage dynamics outer …


Novel Scheduling Algorithm For Optimizing Real-Time Multimedia Performance In Long Term Evolution-Advanced, Huda Adibah Mohd Ramli, Zairi Ismael Rizman Jan 2017

Novel Scheduling Algorithm For Optimizing Real-Time Multimedia Performance In Long Term Evolution-Advanced, Huda Adibah Mohd Ramli, Zairi Ismael Rizman

Turkish Journal of Electrical Engineering and Computer Sciences

Real-time multimedia applications are becoming increasingly popular among mobile cellular users. Given that Long Term Evolution-Advanced (LTE-A), which is an emerging mobile cellular standard, needs to support these multimedia applications, packet scheduling is of paramount importance in LTE-A. This paper proposes a packet scheduling algorithm known as novel scheduling for usage in the downlink of LTE-A. It takes channel quality, average throughput, and packet delay into account when determining the priority of each user. Simulation results demonstrate the efficacy of the proposed algorithm in optimizing real-time multimedia performance for more mobile cellular users.


Sotarm: Size Of Transaction-Based Association Rule Mining Algorithm, Asha Pandian, Jebarajan Thaveethu Jan 2017

Sotarm: Size Of Transaction-Based Association Rule Mining Algorithm, Asha Pandian, Jebarajan Thaveethu

Turkish Journal of Electrical Engineering and Computer Sciences

Mining of association rules tries to identify the existence of promising and fruitful relations among the items present in a database. The basic a priori algorithm suffers from multiple database scans, and if the database is large, then the time taken for scanning and generation of candidates is also large. The proposed algorithm attempts to reduce the repeated scanning of the whole database. Using this algorithm, scanning time and also the generation of subitems that are not frequent can be reduced. The former can be done by sorting the transaction records in descending order based on the size of transaction …


Exploiting Kernel-Based Feature Weighting And Instance Clustering To Transfer Knowledge Across Domains, Jafar Tahmoresnezhad, Sattar Hashemi Jan 2017

Exploiting Kernel-Based Feature Weighting And Instance Clustering To Transfer Knowledge Across Domains, Jafar Tahmoresnezhad, Sattar Hashemi

Turkish Journal of Electrical Engineering and Computer Sciences

Learning invariant features across domains is of vital importance to unsupervised domain adaptation, where classifiers trained on the training examples (source domain) need to adapt to a different set of test examples (target domain) in which no labeled examples are available. In this paper, we propose a novel approach to find the invariant features in the original space and transfer the knowledge across domains. We extract invariant features of input data by a kernel-based feature weighting approach, which exploits distribution difference and instance clustering to find desired features. The proposed method is called the kernel-based feature weighting (KFW) approach and …


A Hybrid Maco And Bfoa Algorithm For Power Loss Minimization And Total Cost Reduction In Distribution Systems, Muthubalaji Sankaramoorthy, Malathi Veluchamy Jan 2017

A Hybrid Maco And Bfoa Algorithm For Power Loss Minimization And Total Cost Reduction In Distribution Systems, Muthubalaji Sankaramoorthy, Malathi Veluchamy

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a multiobjective optimization methodology to optimally place a STATCOM in electric power distribution networks. The combination of multiobjective ant colony optimization (MACO) and the bacterial foraging optimization algorithm (BFOA) is proposed to minimize the power loss and total cost. The main intention of this analysis is to optimally place the STATCOM at multiple locations such as the transmission side, middle, and load side. Identifying the type and location of the STATCOM is a combinatorial optimization problem in power systems. In order to overcome this problem, the combination of hybrid MACO and BFOA algorithms is applied in this …


An Intelligent Approach In Delay Tolerant Network Routing, Azadeh Omidvar, Karim Mohammadi Jan 2017

An Intelligent Approach In Delay Tolerant Network Routing, Azadeh Omidvar, Karim Mohammadi

Turkish Journal of Electrical Engineering and Computer Sciences

Delay tolerant networks (DTNs) are wireless intermittent networks. DTNs have different applications such as wildlife tracking, military, and space searching. Conventional mobile ad hoc network (MANET) routing protocols are not efficient in these networks because of intermittency. DTNs use store-carry-forward (SCF) for data transferring. In SCF, nodes store the messages and carry them until finding appropriate nodes for forwarding. Message replication greatly helps to improve the delivery ratio while increasing overhead. This paper examines the use of intelligent routing to choose nodes that have more probability to reach their destination. This will help to increase the message delivery ratio while …


Implementation Of Svc Based On Grey Theory And Fuzzy Logic To Improve Lvrt Capability Of Wind Distributed Generations, Mohammad Mehdi Karami, Akbar Itami Jan 2017

Implementation Of Svc Based On Grey Theory And Fuzzy Logic To Improve Lvrt Capability Of Wind Distributed Generations, Mohammad Mehdi Karami, Akbar Itami

Turkish Journal of Electrical Engineering and Computer Sciences

Due to the great absorption of reactive power after voltage drops caused by faults in network, the low-voltage ride through (LVRT) capability of squirrel cage induction generators (SCIGs) in wind farms is a great challenge. If a static VAR compensator (SVC) is installed at the point of common coupling (PCC) of a wind farm with a main network, it can improve the wind generation's LVRT capability with reactive power compensation. In the voltage control loop of a conventional SVC, the voltage actual value of the PCC is compared with the reference voltage value. This paper presents a method for implementation …


A New Efficient Block Matching Data Hiding Method Based On Scanning Order Selection In Medical Images, Turgay Aydoğan, Cüneyt Bayilmiş Jan 2017

A New Efficient Block Matching Data Hiding Method Based On Scanning Order Selection In Medical Images, Turgay Aydoğan, Cüneyt Bayilmiş

Turkish Journal of Electrical Engineering and Computer Sciences

Digital technology and the widespread use of the Internet has increased the speeds at which digital data can be obtained and shared in daily life. In parallel to this, there are important concerns regarding the confidentiality of private data during data transmissions and the possibility that data might fall into the hands of third parties. Issues relating to data safety can also affect patients' medical images and other information relating to these images. In this study, we propose a new method based on block matching that can be used to hide the patient information in medical images. In this method, …


Adaptive Control Of Pure-Feedback Systems In The Presence Of Parametric Uncertainties, Mehrnoosh Asadi, Heydar Toossian Shandiz Jan 2017

Adaptive Control Of Pure-Feedback Systems In The Presence Of Parametric Uncertainties, Mehrnoosh Asadi, Heydar Toossian Shandiz

Turkish Journal of Electrical Engineering and Computer Sciences

The purpose of this study is to investigate an adaptive control approach for completely nonaffine pure-feedback systems with linear/nonlinear parameterization. In this approach, the parameter separation technique and the idea of the positive function of linearly connected parameters are coupled effectively with the combination of backstepping and time-scale separation. Subsequently, a fast dynamical equation is derived from the original subsystem, where the solution is sought to approximate the corresponding ideal virtual/actual control inputs. Furthermore, the adaptation law of unknown parameters can be derived based on Lyapunov theory in the backstepping technique and there is no need to design a state …


Design Of A Three-Phase Multistage Axial Flux Permanent Magnet Generator For Wind Turbine Applications, Muhammad Mansoor Ashraf, Tahir Nadeem Malik Jan 2017

Design Of A Three-Phase Multistage Axial Flux Permanent Magnet Generator For Wind Turbine Applications, Muhammad Mansoor Ashraf, Tahir Nadeem Malik

Turkish Journal of Electrical Engineering and Computer Sciences

Presently, axial flux permanent magnet machines are becoming popular and are being deployed actively for low speed applications. This paper presents an improved model of a multistage axial flux permanent magnet generator (AFPMG). The multistage AFPMG consists of multiple stator and rotor discs. There are three identical 1-phase stator discs and four in-phase rotor discs in the proposed multistage AFPMG. In this research, 4 case studies were analyzed on the design of the multistage AFPMG. First, a phase shift model (PSM) positions the three 1-phase stator discs to behave as a 3-phase generator. Actually, the PSM computes phases for three …


Transmission Power Control Using State Estimation-Based Received Signal Strength Prediction For Energy Efficiency In Wireless Sensor Networks, Ramakrishnan Sabitha, Krishna Bhuma, Thangavelu Thyagarajan Jan 2017

Transmission Power Control Using State Estimation-Based Received Signal Strength Prediction For Energy Efficiency In Wireless Sensor Networks, Ramakrishnan Sabitha, Krishna Bhuma, Thangavelu Thyagarajan

Turkish Journal of Electrical Engineering and Computer Sciences

In battery-operated wireless sensor networks, the quality of service requirements such as throughput and energy efficiency must be stringently maintained while the least amount of energy is consumed. Since a major portion of energy is spent by the transceiver operations, transmission power control (TPC) in the medium access control (MAC) layer can bring about considerable energy efficiency. Since TPC algorithms will have a direct impact on the received signal strength index (RSSI) at the receiver, RSSI is the primary input parameter for any TPC algorithm. The objective of the proposed work is to decide on the exact value of transmission …


A New Approach For Digital Image Watermarking To Predict Optimal Blocks Using Artificial Neural Networks, Raheleh Khorsand Movaghar, Hossein Khaleghi Bizaki Jan 2017

A New Approach For Digital Image Watermarking To Predict Optimal Blocks Using Artificial Neural Networks, Raheleh Khorsand Movaghar, Hossein Khaleghi Bizaki

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a novel nonblind digital image watermarking based on discrete wavelet transform and singular value decomposition. This robust scheme takes advantage of artificial neural networks for selecting suitable image blocks in which the watermark signal can be embedded. Local characteristics of the blocks such as luminance and texture sensitivity are the main criteria that the selections are based on. Generally, selection is based on a prediction of the results with the objective of transparency and watermark resilience. In other words, before embedding the water mark signal, it is estimated which blocks would be the best for …


Mutual Correlation Of Nist Statistical Randomness Tests And Comparison Of Their Sensitivities On Transformed Sequences, Ali̇ Doğanaksoy, Fati̇h Sulak, Muhi̇ddi̇n Uğuz, Okan Şeker, Zi̇ya Akcengi̇z Jan 2017

Mutual Correlation Of Nist Statistical Randomness Tests And Comparison Of Their Sensitivities On Transformed Sequences, Ali̇ Doğanaksoy, Fati̇h Sulak, Muhi̇ddi̇n Uğuz, Okan Şeker, Zi̇ya Akcengi̇z

Turkish Journal of Electrical Engineering and Computer Sciences

Random sequences are widely used in many cryptographic applications and hence their generation is one of the main research areas in cryptography. Statistical randomness tests are introduced to detect the weaknesses or nonrandom characteristics that a sequence under consideration may have. In the literature, there exist various statistical randomness tests and test suites, defined as a collection of tests. An efficient test suite should consist of a number of uncorrelated statistical tests each of which measures randomness from another point of view. `Being uncorrelated' is not a well-defined or well-understood concept in the literature. In this work, we apply Pearson's …


Hadoop Framework Implementation And Performance Analysis On A Cloud, Göksu Zeki̇ye Özen, Mehmet Tekerek, Rayi̇mbek Sultanov Jan 2017

Hadoop Framework Implementation And Performance Analysis On A Cloud, Göksu Zeki̇ye Özen, Mehmet Tekerek, Rayi̇mbek Sultanov

Turkish Journal of Electrical Engineering and Computer Sciences

The Hadoop framework uses the MapReduce programming paradigm to process big data by distributing data across a cluster and aggregating. MapReduce is one of the methods used to process big data hosted on large clusters. In this method, jobs are processed by dividing into small pieces and distributing over nodes. Parameters such as distributing method over nodes, the number of jobs held in a parallel fashion, and the number of nodes in the cluster affect the execution time of jobs. The aim of this paper is to determine how the numbers of nodes, maps, and reduces affect the performance of …


A Combined Approach Based On Fuzzy Ahp And Fuzzy Inference System To Rank Reviewers In Online Communities, Hossein Abbasimehr, Mohammadjafar Tarokh Jan 2017

A Combined Approach Based On Fuzzy Ahp And Fuzzy Inference System To Rank Reviewers In Online Communities, Hossein Abbasimehr, Mohammadjafar Tarokh

Turkish Journal of Electrical Engineering and Computer Sciences

Online product review communities allow users to share their ideas and opinions about various products and services. Although online reviews as user-generated content can be considered as an invaluable source of information for both consumers and firms, these reviews tend to be of very different quality. To tackle the problem of low quality reviews, we address reviewer credibility and propose an innovative framework. The framework comprises five critical phases for ranking reviewers in terms of credibility using a fuzzy analytic hierarchy process (AHP) and fuzzy inference system. To determine the weights of the features, a fuzzy AHP method was applied. …


A Metaheuristic Based On The Tabu Search For Hardware-Software Partitioning, Mehdi Jemai, Sonia Dimassi, Bouraoui Ouni, Abdellatif Mtibaa Jan 2017

A Metaheuristic Based On The Tabu Search For Hardware-Software Partitioning, Mehdi Jemai, Sonia Dimassi, Bouraoui Ouni, Abdellatif Mtibaa

Turkish Journal of Electrical Engineering and Computer Sciences

Several metaheuristics have become increasingly interesting in solving combinatorial problems. In this paper, we present an algorithm involving a metaheuristic based on tabu search and binary search trees to address the problem of hardware-software partitioning. Metaheuristics do not guarantee an optimum solution, but they can produce acceptable solutions in a reasonable time. Our proposed algorithm seeks to find the efficient hardware-software partitioning that minimizes the logic area of a system on a programmable chip under the condition of time constraints. Our goal is to have a better trade-off between the logic area of the application and its execution time. Finally, …


Implementation Of A Web-Based Service For Mobile Application Risk Assessment, Asim Si̇nan Yüksel, Mehmet Erkan Yüksel, Ahmet Sertbaş, Abdül Hali̇m Zai̇m Jan 2017

Implementation Of A Web-Based Service For Mobile Application Risk Assessment, Asim Si̇nan Yüksel, Mehmet Erkan Yüksel, Ahmet Sertbaş, Abdül Hali̇m Zai̇m

Turkish Journal of Electrical Engineering and Computer Sciences

The Android operating system has increased in popularity and has been increasing its shares in the smart phone market. Users can carry out their daily work such as paying bills, being social, and sharing photos through mobile applications. These applications have access to sensitive information about the user, such as location, contacts, call logs, and SMS messages. However, the users have no knowledge of the applications or the personal information these applications have access to. Even if an application is not malware or does not have malicious behavior, it can compromise the security and privacy of the user by accessing …


Single Event Multiple Upset-Tolerant Sram Cell Designs For Nano-Scale Cmos Technology, Ramin Rajaei, Bahar Asgari, Mahmoud Tabandeh, Mahdi Fazeli Jan 2017

Single Event Multiple Upset-Tolerant Sram Cell Designs For Nano-Scale Cmos Technology, Ramin Rajaei, Bahar Asgari, Mahmoud Tabandeh, Mahdi Fazeli

Turkish Journal of Electrical Engineering and Computer Sciences

In this article, two soft error tolerant SRAM cells, the so-called RATF1 and RATF2, are proposed and evaluated. The proposed radiation hardened SRAM cells are capable of fully tolerating single event upsets (SEUs). Moreover, they show a high degree of robustness against single event multiple upsets (SEMUs). Over the previous SRAM cells, RATF1 and RATF2 offer lower area and power overhead. The Hspice simulation results through comparison with some prominent and state-of-the-art soft error tolerant SRAM cells show that our proposed robust SRAM cells have smaller area overhead (RAFT1 offers 58% smaller area than DICE), lower power delay product (RATF1 …


Enhanced Hybrid Method Of Divide-And-Conquer And Rbf Neural Networks For Function Approximation Of Complex Problems, Mohammed Awad Jan 2017

Enhanced Hybrid Method Of Divide-And-Conquer And Rbf Neural Networks For Function Approximation Of Complex Problems, Mohammed Awad

Turkish Journal of Electrical Engineering and Computer Sciences

This paper provides an enhanced method focused on reducing the computational complexity of function approximation problems by dividing the input data vectors into small groups, which avoids the curse of dimensionality. The computational complexity and memory requirements of the approximated problem are higher when the input data dimensionality increases. A divide-and-conquer algorithm is used to distribute the input data of the complex problem to a divided radial basis function neural network (Div-RBFNN). Under this algorithm, the input data variables are typically distributed to different RBFNNs based on whether the number of the input data dimensions is odd or even. In …


Electronically Tunable Mos-Only Current-Mode High-Order Band-Pass Filters, Pipat Prommee, Aphinat Tiamsuphat, Muhammad Taher Abuelmaatti Jan 2017

Electronically Tunable Mos-Only Current-Mode High-Order Band-Pass Filters, Pipat Prommee, Aphinat Tiamsuphat, Muhammad Taher Abuelmaatti

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents new CMOS current-mode ladder Chebyshev and elliptic band-pass filters (BPFs). The signal flow graph and the network transformation methods are used to synthesize the proposed BPFs by using Chebyshev and elliptic RLC low-pass prototypes. CMOS-based lossy and lossless integrators with grounded capacitors are used to synthesize the proposed BPFs. The proposed filters can be electronically tuned between 10 kHz and 100 MHz by adjusting the bias current from 0.02 $\mu $A to 200 $\mu $A. Both filters use a 1.5 V DC power supply, which leads to low dynamic power consumption. Both filters enjoy total harmonic distortion …


An Inductorless Wideband Lna With A New Noise Canceling Technique, Pouria Pazhouhesh Moghadam, Adib Abrishamifar Jan 2017

An Inductorless Wideband Lna With A New Noise Canceling Technique, Pouria Pazhouhesh Moghadam, Adib Abrishamifar

Turkish Journal of Electrical Engineering and Computer Sciences

An inductorless wideband low-noise amplifier (LNA) employing a new noise canceling technique for multistandard applications is presented. The main amplifier has a cascode common gate structure, which provides good input impedance matching and isolation. The proposed noise canceling technique not only improves the noise figure and power gain but also embeds a g$_{m}$-boosting technique in itself, which reduces the power consumption of the main amplifier. Using current-steering and current-reuse techniques in the noise canceling branch makes the design realizable and low power. The proposed LNA is simulated and optimized in 0.13 $\mu $m CMOS technology. The LNA achieves a noise …


Protein Fold Classification With Grow-And-Learn Network, Özlem Polat, Zümray Dokur Jan 2017

Protein Fold Classification With Grow-And-Learn Network, Özlem Polat, Zümray Dokur

Turkish Journal of Electrical Engineering and Computer Sciences

Protein fold classification is an important subject in computational biology and a compelling work from the point of machine learning. To deal with such a challenging problem, in this study, we propose a solution method for the classification of protein folds using Grow-and-Learn (GAL) neural network together with one-versus-others (OvO) method. To classify the most common 27 protein folds, 125 dimensional data, constituted by the physicochemical properties of amino acids, are used. The study is conducted on a database including 694 proteins: 311 of these proteins are used for training and 383 of them for testing. Overall, the classification system …


Implementation Of A Flywheel Energy Storage System For Space Applications, Reşat Çeli̇kel, Mehmet Özdemi̇r, Ömür Aydoğmuş Jan 2017

Implementation Of A Flywheel Energy Storage System For Space Applications, Reşat Çeli̇kel, Mehmet Özdemi̇r, Ömür Aydoğmuş

Turkish Journal of Electrical Engineering and Computer Sciences

A satellite power system requires solar panels to provide energy and orientation. There are two regions in the orbital path of the satellite: the dark and bright region. The energy is provided by solar panels in the bright region and by flywheel energy storage system (FESS) in the dark region. Brushless DC (BLDC) motors are widely used in the FESS due to their low weight, high power density, high efficiency, high reliability, and high speed. Some mechanical resonances may occur due to physical features of the mechanical parts. Therefore, the current of the BLDC is dramatically increased because of the …


Maximum Size Of The Pareto Cost Sets For Multi-Constrained Optimal Routing, Derya Yiltaş Kaplan Jan 2017

Maximum Size Of The Pareto Cost Sets For Multi-Constrained Optimal Routing, Derya Yiltaş Kaplan

Turkish Journal of Electrical Engineering and Computer Sciences

Routing under multiple independent constrains in point-to-point networks has been studied for over 10 years. Its NP-hardness keeps pushing researchers to study approximate algorithms and heuristics, and many results have been published in these years. To the best of our knowledge, the nature of its average case has been explored only for the self-adaptive multiple constraints routing algorithm (SAMCRA), which is an algorithm about multiple constraints routing. In this paper, we simplify SAMCRA into a format that is convenient for our average case analysis. This variant algorithm gives optimal solutions also for very large dimensional networks such as with more …