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2017

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Articles 2251 - 2280 of 2767

Full-Text Articles in Computer Sciences

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, …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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Electrical Design And Testing Of A 500 Kw Doubly Fed Induction Generator For Wind Power Applications, Cenk Ulu, Güven Kömürgöz Jan 2017

Electrical Design And Testing Of A 500 Kw Doubly Fed Induction Generator For Wind Power Applications, Cenk Ulu, Güven Kömürgöz

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the electrical design and testing of a 500 kW doubly fed induction generator (DFIG) is presented, developed in the context of the MILRES (Turkish National Wind Energy Systems) Project. The main objective of the MILRES Project is to encourage locally produced equipment for wind power systems. Therefore, in the DFIG design, the standard construction capabilities of the local machine manufacturers are especially taken into consideration. In this way, it is aimed that the designed DFIG can easily and cost-effectively be manufactured by local machine manufacturers in Turkey. In the DFIG design procedure, initially, an analytical design of …

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An Advanced Robust Fault-Tolerant Tracking Control For A Doubly Fed Induction Generator With Actuator Faults, Samir Abdelmalek, Linda Barazane, Abdelkader Larabi Jan 2017

An Advanced Robust Fault-Tolerant Tracking Control For A Doubly Fed Induction Generator With Actuator Faults, Samir Abdelmalek, Linda Barazane, Abdelkader Larabi

Turkish Journal of Electrical Engineering and Computer Sciences

Fault-tolerant controller (FTC) designs for doubly fed induction generators (DFIGs) with actuator faults have recently gained considerable attention due to their important role in maintaining the safety and reliability of DFIG-based wind turbines via configured redundancy. The objective of this paper is to propose a novel active fault-tolerant tracking control strategy for a DFIG subject to actuator faults. The proposed strategy consists of first designing a proportional integral observer (PIO) for simultaneous system states and fault estimation and then secondly the FTC, which depends on the estimated states and faults. The objective of such a controller is to drive the …

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Rapidly Converging Solution For P-Centers In Nonconvex Regions, Monika Mangla, Deepak Garg Jan 2017

Rapidly Converging Solution For P-Centers In Nonconvex Regions, Monika Mangla, Deepak Garg

Turkish Journal of Electrical Engineering and Computer Sciences

This paper aims to locate $p$ resources in a nonconvex demand plane having $n $demand points. The objective of the location problem is to find the location for these $p$ resources so that the distance from each of $n$ demand points to its nearest resource is minimized, thus simulating a $p$-center problem. We employ various geometrical structures for solving this location problem. The suggested approach is also capable of finding the optimal value of $p$ so that all demand points have at least one resource at a distance $\Delta $, where $\Delta $ is the maximum permissible distance for emergency …

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Analysis And Design Of Grid-Connected 3-Phase 3-Level At-Npc Inverter For Low-Voltage Applications, Emre Avci, Mehmet Uçar Jan 2017

Analysis And Design Of Grid-Connected 3-Phase 3-Level At-Npc Inverter For Low-Voltage Applications, Emre Avci, Mehmet Uçar

Turkish Journal of Electrical Engineering and Computer Sciences

The 3-level T-type neutral point clamped (T-NPC) inverter has become the most popular multilevel inverter used in low-voltage applications. However, the realization of a bidirectional switch located at the midpoint leg of the T-NPC inverter is achieved using two insulated gate bipolar transistors (IGBTs) with two antiparallel diodes. Power dissipation in these switches is high since there are two semiconductors (an IGBT and a diode) in the current path at the midpoint leg. Switch losses can be reduced and thus the highest conversion efficiency can be achieved if the bidirectional switches in the T-NPC inverter are replaced by highly efficient …

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Designing A Vm-Level Vertical Scalability Service In Current Cloud Platforms: A New Hope For Wearable Computers, Mustafa Kaiiali Jan 2017

Designing A Vm-Level Vertical Scalability Service In Current Cloud Platforms: A New Hope For Wearable Computers, Mustafa Kaiiali

Turkish Journal of Electrical Engineering and Computer Sciences

Public clouds are becoming ripe for enterprise adoption. Many companies, including large enterprises, are increasingly relying on public clouds as a substitute for, or a supplement to, their own computing infrastructures. On the other hand, cloud storage service has attracted over 625 million users. However, apart from the storage service, other cloud services, such as the computing service, have not yet attracted the end users' interest for economic and technical reasons. Cloud service providers offers horizontal scalability to make their services scalable and economical for enterprises while it is still not economical for the individual users to use their computing …

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Paper Recommendation Using Citation Proximity In Bibliographic Coupling, Raja Habib, Muhammad Tanvir Afzal Jan 2017

Paper Recommendation Using Citation Proximity In Bibliographic Coupling, Raja Habib, Muhammad Tanvir Afzal

Turkish Journal of Electrical Engineering and Computer Sciences

Research paper recommendation has been a hot research area for the last few decades. Thus far, numerous different paper recommendation approaches have been proposed. Some of these include methods based on metadata, content similarity, collaborative filtering, and citation analysis, among others. Citation analysis methods include bibliographic coupling and co-citation analysis. Much research has been done in the area of co-citation analysis. Researchers have also performed experiments using the proximity of in-text citations in co-citation analysis and have found that it improves the accuracy of paper recommendation. In co-citation analysis, the similarity is discovered based on the frequency of co-cited papers …

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An Experimental Study Of Indoor Rss-Based Rf Fingerprinting Localization Using Gsm And Wi-Fi Signals, Gökhan Çeli̇k, Hasari̇ Çelebi̇, Hakan Paşa Partal, Engi̇n Zeydan, İlyas Alper Karatepe, Ahmet Sali̇h Er Jan 2017

An Experimental Study Of Indoor Rss-Based Rf Fingerprinting Localization Using Gsm And Wi-Fi Signals, Gökhan Çeli̇k, Hasari̇ Çelebi̇, Hakan Paşa Partal, Engi̇n Zeydan, İlyas Alper Karatepe, Ahmet Sali̇h Er

Turkish Journal of Electrical Engineering and Computer Sciences

Localization of mobile users in indoor environments has many practical applications in daily life. In this paper, we study the performance of the received signal strength (RSS)-based radio frequency (RF) fingerprinting localization method in a shopping mall environment considering both calibration and practical measurement cases. In the calibration case, the test data for the RSS fingerprinting database are built offline by receiving signals from Global System for Mobile Communications (GSM) base stations, which are collected by a dedicated measurement tool, i.e. the Test Mobile System. In order to see the localization performance, the k-nearest neighbors (K-NN) and random decision forest …

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A Parametric Battery State Of Health Estimation Method For Electric Vehicle Applications, Türev Sarikurt, Murat Ceylan, Abdulkadi̇r Balikçi Jan 2017

A Parametric Battery State Of Health Estimation Method For Electric Vehicle Applications, Türev Sarikurt, Murat Ceylan, Abdulkadi̇r Balikçi

Turkish Journal of Electrical Engineering and Computer Sciences

Lithium-ion batteries are commonly preferred in electric vehicle applications. The relative capacity and state of health of a battery decrease with age. Therefore, accurate estimation of these parameters is essential. In this study a parametrical approach for estimation of battery state of health is proposed. A hybrid battery model that has a maximum error less than 3% is used. The relative capacity of the battery is estimated by using performance decrement with age. The method is validated by two different set of experiments. The first set is conducted with batteries that were aged by a controlled process and the second …

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Two-Group Decodable Distributed Differential Space-Time Code For Wireless Relay Networks Based On Sast Codes, Obada Abdallah, Ammar Abu Hudrouss Jan 2017

Two-Group Decodable Distributed Differential Space-Time Code For Wireless Relay Networks Based On Sast Codes, Obada Abdallah, Ammar Abu Hudrouss

Turkish Journal of Electrical Engineering and Computer Sciences

Space-time code can be implemented in wireless relay networks when all relays cooperate to generate the code at the receiver. In this case, it is called distributed space-time code. If the channel response changes very quickly, the idea of differential space-time coding is needed to overcome the difficulty of updating the channel state information at the receiver. As a result, the transmitted signal can be demodulated without any knowledge of the channel state information at the relays or the receiver. In this paper, development of new low decoding complexity distributed differential space-time codes is considered. The developed codes are designed …

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An Ultralow Power, 0.003-Mm$^{2}$ Area, Voltage To Frequency-Based Smart Temperature Sensor For -55 $^{\Circ}$C To +125 $^{\Circ}$C With One-Point Calibration, Mudasir Bashir, Sreehari Rao Patri, Krishnaprasad Ksr Jan 2017

An Ultralow Power, 0.003-Mm$^{2}$ Area, Voltage To Frequency-Based Smart Temperature Sensor For -55 $^{\Circ}$C To +125 $^{\Circ}$C With One-Point Calibration, Mudasir Bashir, Sreehari Rao Patri, Krishnaprasad Ksr

Turkish Journal of Electrical Engineering and Computer Sciences

With the scaling of transistor feature size and increased integration density, power density has increased, resulting in high chip temperature, thus degrading the performance and lifetime of the chip. In this work, an ultralow power smart temperature sensor employing a frequency locked loop technique is developed in 65 nm standard CMOS process. The circuit works on the principle of voltage to frequency conversion, exploiting the thermal dependency of threshold voltage (V$_{th})$ of MOS transistors in the subthreshold region. The sensor along with signal conditioning subcircuits has a low power consumption of 1.92 $\mu $W, while operating over -55 $^{\circ}$C to …

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Mopso-Based Predictive Control Strategy For Efficient Operation Of Sensorless Vector-Controlled Fuel Cell Electric Vehicle Induction Motor Drives, Adel Abdelaziz Abdelghany Elgammal, Mohammed Fathy El_Naggar Jan 2017

Mopso-Based Predictive Control Strategy For Efficient Operation Of Sensorless Vector-Controlled Fuel Cell Electric Vehicle Induction Motor Drives, Adel Abdelaziz Abdelghany Elgammal, Mohammed Fathy El_Naggar

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces an optimal control strategy of model-based predictive control (MPC) based on multiobjective particle swarm optimization (MOPSO) for a sensorless vector control induction motor, which is used in a fuel cell electric vehicle drive system. The proposed MPC-MOPSO algorithm is implemented to tune the weighting parameters of the MPC controller to tackle all the conflicting objective functions. The paper handles the following fitness functions: minimizing the speed error, minimizing the torque ripple, minimizing the DC-link voltage ripple, and minimizing machine flux ripple. Computer simulations studies have been completed utilizing MATLAB/Simulink with a specific end goal of assessing the …

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Flexible (2 $\Times $ 1) Mimo Antenna With Electromagnetic Band Gap Unit Cell For Wimax Applications, Hussein Qasim Al-Fayyadh, Abdulghafor Abdulghafar Abdulhameed, Abdulkareem Swadi Abdullah, Haider Mohammed Alsabbagh Jan 2017

Flexible (2 $\Times $ 1) Mimo Antenna With Electromagnetic Band Gap Unit Cell For Wimax Applications, Hussein Qasim Al-Fayyadh, Abdulghafor Abdulghafar Abdulhameed, Abdulkareem Swadi Abdullah, Haider Mohammed Alsabbagh

Turkish Journal of Electrical Engineering and Computer Sciences

A flexible (2 $\times $ 1) multiple-input, multiple-output (MIMO) antenna with an electromagnetic band gap (EBG) unit cell is designed and measured. The proposed MIMO antenna is based on a circular slotted patch antenna to work at 3.5 GHz. An EBG unit cell is used to reduce the effect of the inherent mutual coupling produced between the closely spaced MIMO elements. The results show that the measured mutual coupling has been reduced by -11.6 dB (from -10 dB to -21.6 dB), and the measured realized gain has been increased by 1.074 dBi (from 1.59 dBi to 2.66 dBi). An improvement …

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A New Sequential Power Flow Algorithm For Ac/Dc Systems Including Independent Multiterminal Dc Subsystems, Faruk Yalçin, Uğur Ari̇foğlu Jan 2017

A New Sequential Power Flow Algorithm For Ac/Dc Systems Including Independent Multiterminal Dc Subsystems, Faruk Yalçin, Uğur Ari̇foğlu

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new algorithm based on the sequential method for power flow calculation in multiterminal AC/DC systems. The proposed approach differs from other similar studies in the literature by handling two main properties. Firstly, a real equivalent circuit model is considered for the under-load tap changer transformers (ULTCs) of DC converters for the first time in the literature. Hence, new DC equations are obtained. Thus, exact and accurate results can be obtained for practical applications using the proposed algorithm. Tap values adjustment effects of the ULTCs connected to DC converters are included into the Jacobian matrix instead of …

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Tsgv: A Table-Like Structure-Based Greedy Method For Materialized View Selection In Data Warehouses, Mohammad Karim Sohrabi, Hossein Azgomi Jan 2017

Tsgv: A Table-Like Structure-Based Greedy Method For Materialized View Selection In Data Warehouses, Mohammad Karim Sohrabi, Hossein Azgomi

Turkish Journal of Electrical Engineering and Computer Sciences

Since a data warehouse deals with huge amounts of data and complex analytical queries, online processing and answering to users' queries in data warehouses can be a serious challenge. Materialized views are used to speed up query processing rather than direct access to the database in on-line analytical processing. Since the large number and high volume of views prevents all of the views from being stored, selection of a proper subset of views to materialization is inevitable. Proposing an appropriate method for selecting the optimal subset of views for materialization plays an essential role in increasing the efficiency of responding …

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Unsupervised Learning Of Allomorphs In Turkish, Burcu Can Jan 2017

Unsupervised Learning Of Allomorphs In Turkish, Burcu Can

Turkish Journal of Electrical Engineering and Computer Sciences

One morpheme may have several surface forms that correspond to allomorphs. In English, ed and $d$ are surface forms of the past tense morpheme, and $s$, es, and ies are surface forms of the plural or present tense morpheme. Turkish has a large number of allomorphs due to its morphophonemic processes. One morpheme can have tens of different surface forms in Turkish. This leads to a sparsity problem in natural language processing tasks in Turkish. Detection of allomorphs has not been studied much because of its difficulty. For example, tü and di are Turkish allomorphs (i.e. past tense morpheme), but …

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Instantaneous Protection Scheme For Backup Protection Of High-Voltage Transmission Lines, Syed Norazizul Syed Nasir, Abdullah Asuhaimi Jan 2017

Instantaneous Protection Scheme For Backup Protection Of High-Voltage Transmission Lines, Syed Norazizul Syed Nasir, Abdullah Asuhaimi

Turkish Journal of Electrical Engineering and Computer Sciences

The protection scheme focused on in this study is a typical protection system used in high-voltage systems such as 132 kV, 275 kV, and 500 kV. The research will analyze the existing protection scheme for transmission lines that the power utility has implemented and will propose a new protection scheme to improve the performance of the existing scheme. The existing protection scheme currently implemented by the power utility for backup protection operation has a longer fault-clearing time and no restoration time, and it does not utilize support relays. This study will focus on a backup protection operation on high-voltage overhead …

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High-Voltage Isolated Multioutput Power Supply For Multilevel Converters, Amir Sepehr, Mehdi Saradarzadeh, Shahrokh Farhangi Jan 2017

High-Voltage Isolated Multioutput Power Supply For Multilevel Converters, Amir Sepehr, Mehdi Saradarzadeh, Shahrokh Farhangi

Turkish Journal of Electrical Engineering and Computer Sciences

Multilevel converters are one of the major choices for realizing high electric power conversion. The major feature of multilevel converter topologies is the need for a large number of switches, each of which requires a gate driver circuit and an isolated DC power supply. In this paper, a pragmatic concept of design and implementation of an isolated DC-to-DC converter for a high-voltage isolated application is introduced. More specifically, a multiple isolated output power supply based on the benefits of resonant converters is designed to prepare 36 double DC voltages for driving power semiconductor devices in a three-phase, seven-level cascaded H-bridge …

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An Alternative Approach To The Design Of Multiple Beam Constrained Lens Antennas, Rasi̇me Uyguroğlu, Abdullah Yücel Öztoprak Jan 2017

An Alternative Approach To The Design Of Multiple Beam Constrained Lens Antennas, Rasi̇me Uyguroğlu, Abdullah Yücel Öztoprak

Turkish Journal of Electrical Engineering and Computer Sciences

Rotman lenses are constrained lenses that are used as beam-forming networks to feed array antennas. Their design is based on three focal points, producing three beams with perfect phase fronts. This paper introduces an alternative constrained lens, which has phase equality at five radiating array elements for each beam position. In addition, the center point of the feed curve produces a perfect beam at broadside. The performance of this lens is analyzed and compared to the conventional Rotman lens. The analysis demonstrates that the new lens has better phase performance for wide angle designs. Our study shows that the phase …

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Classification Of Eeg Signals Of Familiar And Unfamiliar Face Stimuli Exploiting Most Discriminative Channels, Abdurrahman Özbeyaz, Sami̇ Arica Jan 2017

Classification Of Eeg Signals Of Familiar And Unfamiliar Face Stimuli Exploiting Most Discriminative Channels, Abdurrahman Özbeyaz, Sami̇ Arica

Turkish Journal of Electrical Engineering and Computer Sciences

The objective of the study is to classify electroencephalogram signals recorded in a familiar and unfamiliar face recognition experiment. Frontal views of familiar and unfamiliar face images were shown to 10 volunteers in different sessions. In contrast to previous studies, no marker button was used during the experiment. Participants had to decide whether the displayed face was familiar or unfamiliar at the instant of stimulus presentation. The signals were analyzed in the preprocessing, channel selection, feature extraction, and classification stages. The novel two-feature extraction and eight-channel selection methods were applied to the analyses. Sixteen classification results were compared and the …

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Access Pattern-Aware Data Placement For Hybrid Dram/Nvm, Di̇dem Unat Erten Jan 2017

Access Pattern-Aware Data Placement For Hybrid Dram/Nvm, Di̇dem Unat Erten

Turkish Journal of Electrical Engineering and Computer Sciences

In recent years, increased interest in data-centric applications has led to an increasing demand for large-capacity memory systems. Nonvolatile memory (NVM) technologies enable new opportunities in terms of process-scaling and energy consumption, and have become an attractive memory technology that serves as a secondary memory at low cost. However, NVM has certain disadvantages for write references, due to its high dynamic energy consumption for writes and low bandwidth compared to DRAM writes. In this paper, we propose an access-aware placement of objects in the application code for two types of memories. Given the desired power savings and acceptable performance loss, …

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An Rc-Triggered Esd Clamp For High-Voltage Bcd Cmos Processes, Fati̇h Koçer Jan 2017

An Rc-Triggered Esd Clamp For High-Voltage Bcd Cmos Processes, Fati̇h Koçer

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a novel RC-triggered, field-effect transistor (FET)-based power clamp that can be used in high-voltage complementary metal oxide semiconductor (CMOS) processes. A simple two-stage design provides a fast trigger while keeping the clamp transistor on for much longer than the triggering duration without the need for an additional digital latching circuit. As the presented technique does not require any digital circuits, it is especially useful in bipolar-CMOS-DMOS (BCD) processes, where the implementation of digital blocks is difficult due to the limited gate-to-source voltage of the laterally diffused metal oxide semiconductor (LDMOS) transistors. The proposed architecture is implemented in …

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