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2013

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Articles 11011 - 11040 of 11462

Full-Text Articles in Physical Sciences and Mathematics

High-Performance Cmos Cci In A 0.35 \Mu M Cmos Technology And A New All-Pass Filter Application, Emre Arslan, Bi̇lgi̇n Meti̇n, Mehmet Oğuzhan Çi̇çekoğlu, Avni̇ Morgül Jan 2013

High-Performance Cmos Cci In A 0.35 \Mu M Cmos Technology And A New All-Pass Filter Application, Emre Arslan, Bi̇lgi̇n Meti̇n, Mehmet Oğuzhan Çi̇çekoğlu, Avni̇ Morgül

Turkish Journal of Electrical Engineering and Computer Sciences

A differential pair-based, high-performance, first-generation current conveyor is proposed. The proposed circuit is laid out using the Mentor Graphics IC Station layout editor. The performance characteristics have been determined from HSpice postlayout simulations using the Austria Mikro Systeme 0.35 \mu m, 3.3 V process parameters. During the simulations, \pm 1.65 V supply voltages and a 25 \mu A biasing current are used. The power consumption is about 1.12 mW. The circuit also has very high voltage swings on ports X and Y, a very small impedance value on port X, high impedance values on ports Y and Z, and high-valued …

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A Novel Uwb Cpw-Fed Ring-Shaped Antenna With Band-Notched Characteristics, Maryam Majidzadeh, Changiz Ghobadi Jan 2013

A Novel Uwb Cpw-Fed Ring-Shaped Antenna With Band-Notched Characteristics, Maryam Majidzadeh, Changiz Ghobadi

Turkish Journal of Electrical Engineering and Computer Sciences

A novel compact omnidirectional coplanar waveguide (CPW)-fed antenna with band-notched characteristics has been designed and analyzed. The proposed ultra-wideband (UWB) antenna has a simple structure. A ring-shaped radiating patch is excited by a CPW feed line. By creating 2 square slots on the top corners of the antenna, a new resonance is excited and the bandwidth is enhanced. The band-notched function is achieved by applying 2 rectangular stubs to the ground plane structure. The proposed antenna occupies a small size of 20 x 20 x 1 mm^3 and covers a wide frequency range of 3.1--14 GHz, except for 5--6 GHz, …

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Opposition-Based Discrete Action Reinforcement Learning Automata Algorithm Case Study: Optimal Design Of A Pid Controller, Fatemeh Mohseni Pour, Ali Akbar Gharaveisi Jan 2013

Opposition-Based Discrete Action Reinforcement Learning Automata Algorithm Case Study: Optimal Design Of A Pid Controller, Fatemeh Mohseni Pour, Ali Akbar Gharaveisi

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the discrete action reinforcement learning automata (DARLA) method is expressed. The performance of the reinforcement learning algorithm is improved using the opposite concepts. This is an automatic method that can find the global optima without any knowledge about the parameters of the research space. To find the global optimal point, the interval that contains the optima is determined by DARLA as the cost function is minimized. In the opposition-based DARLA method, learning is performed based on opposition. The main idea in the opposition is to consider the search direction and its opposite at the same time to …

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K-Means Algorithm With A Novel Distance Measure, Shadi Abudalfa, Mohammad Mikki Jan 2013

K-Means Algorithm With A Novel Distance Measure, Shadi Abudalfa, Mohammad Mikki

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we describe an essential problem in data clustering and present some solutions for it. We investigated using distance measures other than Euclidean type for improving the performance of clustering. We also developed an improved point symmetry-based distance measure and proved its efficiency. We developed a k-means algorithm with a novel distance measure that improves the performance of the classical k-means algorithm. The proposed algorithm does not have the worst-case bound on running time that exists in many similar algorithms in the literature. Experimental results shown in this paper demonstrate the effectiveness of the proposed algorithm. We compared …

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Interaction Analysis Of Multi-Function Facts And D-Facts Controllers By Mrga, Maghsood Mokhtari, Javad Khazaie, Daryoush Nazarpour, Morteza Farsadi Jan 2013

Interaction Analysis Of Multi-Function Facts And D-Facts Controllers By Mrga, Maghsood Mokhtari, Javad Khazaie, Daryoush Nazarpour, Morteza Farsadi

Turkish Journal of Electrical Engineering and Computer Sciences

With the growing application of flexible AC transmission systems (FACTS) and distributed FACTS (D-FACTS), the coordinating problem of FACTS and D-FACTS controllers in joint operation must be considered in modern power systems. The main purpose of this paper is to investigate the possible interaction that may occur between the distributed static series compensator (DSSC) and the static synchronous compensator (STATCOM) when they operate concurrently in the power system. The modified relative gain array (MRGA) is implemented to analyze the interactions. The application of MRGA for the effective design of multiobjective controllers of the STATCOM and DSSC is demonstrated by 2 …

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Performance Evolution Of A Newly Developed General-Use Hybrid Ais-Ann System: Aaa-Response, Seral Özşen, Sali̇h Güneş Jan 2013

Performance Evolution Of A Newly Developed General-Use Hybrid Ais-Ann System: Aaa-Response, Seral Özşen, Sali̇h Güneş

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we have developed a nonlinear recognition system in the artificial immune systems (AIS) field named `AaA-response (artificial neural network (ANN)-aided AIS-response)', which is different from previous AIS methods in that it uses a different modeling strategy in the formation of the memory response. Because it also uses ANNs in the determination of the correct output, it can be seen as a hybrid system that involves AIS and ANN approaches. Unlike the other AIS methods, AaA-response uses multiple system units (or antibodies) to form an output for a presented input. This property gives the proposed system the ability …

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Discrete Event Simulation-Based Performance Evaluation Of Internet Routing Protocols, Fati̇h Çeli̇k, Ahmet Zengi̇n, Bülent Çobanoğlu Jan 2013

Discrete Event Simulation-Based Performance Evaluation Of Internet Routing Protocols, Fati̇h Çeli̇k, Ahmet Zengi̇n, Bülent Çobanoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a discrete event system specification (DEVS)-based comparative performance analysis between the open shortest path first (OSPF) protocol and the routing information protocol (RIP), together with the border gateway protocol (BGP), using DEVS-Suite. In order to evaluate the OSPF and RIP's scalability performance, several network models are designed and configured with the OSPF and RIP, in combination with the BGP. Evaluations of the proposed routing protocols are performed based on the metrics, such as the execution time, convergence time, turnaround time, throughput, and efficiency across an increasing size and complexity through the simulated network models. The evaluation results …

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Hybrid Of Genetic Algorithm And Great Deluge Algorithm For Rough Set Attribute Reduction, Najmeh Sadat Jaddi, Salwani Abdullah Jan 2013

Hybrid Of Genetic Algorithm And Great Deluge Algorithm For Rough Set Attribute Reduction, Najmeh Sadat Jaddi, Salwani Abdullah

Turkish Journal of Electrical Engineering and Computer Sciences

The attribute reduction problem is the process of reducing unimportant attributes from a decision system to decrease the difficulty of data mining or knowledge discovery tasks. Many algorithms have been used to optimize this problem in rough set theory. The genetic algorithm (GA) is one of the algorithms that has already been applied to optimize this problem. This paper proposes 2 kinds of memetic algorithms, which are a hybridization of the GA, with 2 versions (linear and nonlinear) of the great deluge (GD) algorithm. The purpose of this hybridization is to investigate the ability of this local search algorithm to …

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Cada: Channel And Delay Aware Scheduler For Real-Time Applications In Wimax Networks, Melek Oktay, Haci Ali̇ Mantar Jan 2013

Cada: Channel And Delay Aware Scheduler For Real-Time Applications In Wimax Networks, Melek Oktay, Haci Ali̇ Mantar

Turkish Journal of Electrical Engineering and Computer Sciences

Scheduling is the core of the worldwide interoperability for microwave access (WiMAX) technology that directly affects the performance of the network. In this study, we focus on scheduling and present a novel algorithm called the channel and delay aware scheduler (CADA) for real-time applications, such as voice over Internet protocol, video-on-demand, and video streaming. CADA has 2 important modules: wireless and network delay monitoring tools. The wireless module, including the compensation and channel state monitoring modules, increases the network throughput and provides fairness among all of the flows in the network. The network delay monitoring tool calculates the estimated network …

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Estimation Of Fuel Cost Curve Parameters For Thermal Power Plants Using The Abc Algorithm, Yusuf Sönmez Jan 2013

Estimation Of Fuel Cost Curve Parameters For Thermal Power Plants Using The Abc Algorithm, Yusuf Sönmez

Turkish Journal of Electrical Engineering and Computer Sciences

The solution accuracy of economic dispatch problems is associated with the accuracy of the fuel cost curve parameters. Therefore, updating of these parameters is a very important issue to further improve the final accuracy of economic dispatch problems. Estimating the parameters of the fuel cost curve may be the best solution for this issue. This paper presents an application of the artificial bee colony (ABC) algorithm to estimate the fuel cost curve parameters of thermal power plants. In the estimation problem, 1st-, 2nd-, and 3rd-order fuel cost functions are used, and the estimation problem is formulated as an optimization one. …

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Improving Power Systems Operation Through Multiobjective Optimal Location Of Optimal Unified Power Flow Controller, Afshin Lashkar Ara, Ahad Kazemi, Mohammad Behshad Jan 2013

Improving Power Systems Operation Through Multiobjective Optimal Location Of Optimal Unified Power Flow Controller, Afshin Lashkar Ara, Ahad Kazemi, Mohammad Behshad

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a multiobjective optimization methodology to find the optimal location for an optimal unified power flow controller (OUPFC) device. Moreover, the installation cost function of the OUPFC device is developed. The objective functions are the total fuel cost, power losses, and system loadability with and without the minimum cost of the OUPFC installation. The \varepsilon-constraint approach is implemented for the multiobjective mathematical programming formulation. The proposed algorithm is implemented in the IEEE 30- and 118-bus test systems. The solution procedure uses nonlinear programming to optimally locate the OUPFC incorporated in an optimal power flow problem considering these objective …

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Optimal Iterative Learning Control Design For Generator Voltage Regulation System, Mohsen Rezaei Estakhrouieh, Ali Akbar Gharaveisi Jan 2013

Optimal Iterative Learning Control Design For Generator Voltage Regulation System, Mohsen Rezaei Estakhrouieh, Ali Akbar Gharaveisi

Turkish Journal of Electrical Engineering and Computer Sciences

The purpose of this paper is to design a good tracking controller for the generator automatic voltage regulator (AVR) system. It uses an iterative learning control (ILC) algorithm as a control rule and tries to keep voltage error as low as possible, while replying to set point changes as fast as possible. Two models of ILC are discussed: P-type learning and linear quadratic (LQ) optimal design. The results of designing by LQ optimal method are compared with a Ziegler--Nichols proportional-integral-derivative (PID) controller. The effects of changing different parameters are investigated and illustrated by simulation. In order to provide better robustness …

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Using The Csm And Vsm Techniques To Speed Up The Ica Algorithm Without A Loss Of Quality, Mahdi Mahdikhani, Mohammad Hosein Kahaei Jan 2013

Using The Csm And Vsm Techniques To Speed Up The Ica Algorithm Without A Loss Of Quality, Mahdi Mahdikhani, Mohammad Hosein Kahaei

Turkish Journal of Electrical Engineering and Computer Sciences

In blind source separation problems that are implemented based on the independent component analysis (ICA) algorithm, the separation speed and quality are related inversely. In this paper, the proposed algorithms eliminate this tradeoff by generating a faster separation while maintaining the quality. In the proposed algorithms, in each frequency bin and in all of the learning steps, the separation quality of the separating matrix is compared with another one that we define as a situated matrix, and the best matrix is considered as an initial separating matrix in the next learning step. In this paper, we propose 2 algorithms based …

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Simulation Of Discrete Electromagnetic Propagation Model For Atmospheric Effects On Mobile Communication, Şaban Seli̇m Şeker, Fulya Kunter Jan 2013

Simulation Of Discrete Electromagnetic Propagation Model For Atmospheric Effects On Mobile Communication, Şaban Seli̇m Şeker, Fulya Kunter

Turkish Journal of Electrical Engineering and Computer Sciences

Wireless communication has become an important part of our lives, and atmospheric effects are one of the ultimate factors affecting quality of communication and satellite systems. In this study the attenuation in mobile communication due to atmospheric events like snow and rain is simulated using the discrete propagation model. In this work, spherical raindrop and oblate spheroid raindrop modeling are used. To check the validity of simulations, the commonly used and accepted ITU-R rain model is used. Oblate spheroid raindrop modeling produces results that are more compatible with ITU-R results, especially at frequencies higher than 50 GHz. At lower frequencies, …

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Fuzzified Artificial Bee Colony Algorithm For Nonsmooth And Nonconvex Multiobjective Economic Dispatch Problem, Chandrasekaran Koodalsamy, Sishaj Pulikottil Simon Jan 2013

Fuzzified Artificial Bee Colony Algorithm For Nonsmooth And Nonconvex Multiobjective Economic Dispatch Problem, Chandrasekaran Koodalsamy, Sishaj Pulikottil Simon

Turkish Journal of Electrical Engineering and Computer Sciences

The economic dispatch (ED) problem is one of the important optimization problems in power system operation. Recently the power system has stressed the need for reliable, nonpolluting, and economic operation. Hence, 3 conflicting functions of reliability, emission, and fuel cost are considered in the objective function of the proposed ED problem. The problem is formulated as a nonsmooth and nonconvex problem when the valve-point effects of thermal units are considered in the proposed reliable emission and economic dispatch (REED) problem. This paper presents a multiobjective optimization methodology for solving the newly developed REED problem using a fuzzified artificial bee colony …

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An Efficient Solving Of The Traveling Salesman Problem: The Ant Colony System Having Parameters Optimized By The Taguchi Method, Musa Peker, Baha Şen, Pinar Yildiz Kumru Jan 2013

An Efficient Solving Of The Traveling Salesman Problem: The Ant Colony System Having Parameters Optimized By The Taguchi Method, Musa Peker, Baha Şen, Pinar Yildiz Kumru

Turkish Journal of Electrical Engineering and Computer Sciences

Owing to its complexity, the traveling salesman problem (TSP) is one of the most intensively studied problems in computational mathematics. The TSP is defined as the provision of minimization of total distance, cost, and duration by visiting the n number of points only once in order to arrive at the starting point. Various heuristic algorithms used in many fields have been developed to solve this problem. In this study, a solution was proposed for the TSP using the ant colony system and parameter optimization was taken from the Taguchi method. The implementation was tested by various data sets in the …

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Discovery Of The Connection Among Age-Related Macular Degeneration, Mthfr C677t And Pai 1 4g/5g Gene Polymorphisms, And Body Mass Index By Means Of Bayesian Inference Methods, Aydan Çelebi̇ler, Huseyin Seker, Bora Yüksel, Ahmet Orun, Si̇bel Bi̇lgi̇li̇, Muhammet Baysal Karaca Jan 2013

Discovery Of The Connection Among Age-Related Macular Degeneration, Mthfr C677t And Pai 1 4g/5g Gene Polymorphisms, And Body Mass Index By Means Of Bayesian Inference Methods, Aydan Çelebi̇ler, Huseyin Seker, Bora Yüksel, Ahmet Orun, Si̇bel Bi̇lgi̇li̇, Muhammet Baysal Karaca

Turkish Journal of Electrical Engineering and Computer Sciences

Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly. The aim of this study was therefore to explore the relationship between the presence of multiple gene polymorphisms and 2 distinct advanced `dry and wet' AMD phenotypes, and to assess gene interactions with the influence of personal factors in a Turkish population as a pilot study. For the analysis, the data were collected from 73 unrelated participants, grouped as 29 wet and 26 dry AMD patients, and 18 healthy controls. They were all genotyped for the multiple gene polymorphisms in 12 different genes. The data set …

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A New Intelligent Classifier For Breast Cancer Diagnosis Based On A Rough Set And Extreme Learning Machine: Rs + Elm, Yilmaz Kaya Jan 2013

A New Intelligent Classifier For Breast Cancer Diagnosis Based On A Rough Set And Extreme Learning Machine: Rs + Elm, Yilmaz Kaya

Turkish Journal of Electrical Engineering and Computer Sciences

Breast cancer is one of the leading causes of death among women all around the world. Therefore, true and early diagnosis of breast cancer is an important problem. The rough set (RS) and extreme learning machine (ELM) methods were used collectively in this study for the diagnosis of breast cancer. The unnecessary attributes were discarded from the dataset by means of the RS approach. The classification process by means of ELM was performed using the remaining attributes. The Wisconsin Breast Cancer dataset (WBCD), derived from the University of California Irvine machine learning database, was used for the purpose of testing …

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Swarm Optimization Tuned Mamdani Fuzzy Controller For Diabetes Delayed Model, Mohammad Hassan Khooban, Davood Nazari Maryam Abadi, Alireza Alfi, Mehdi Siahi Jan 2013

Swarm Optimization Tuned Mamdani Fuzzy Controller For Diabetes Delayed Model, Mohammad Hassan Khooban, Davood Nazari Maryam Abadi, Alireza Alfi, Mehdi Siahi

Turkish Journal of Electrical Engineering and Computer Sciences

Diabetes is a chronic disease in which there are high levels of sugar in the blood. Insulin is a hormone that regulates the blood glucose level in the body. Diabetes mellitus can be caused by too little insulin, a resistance to insulin, or both. Although research activities on controlling blood glucose have been attempted to lower the blood glucose level in the quickest possible time, there are some shortages in the amount of the insulin injection. In this paper, a complete model of the glucose--insulin regulation system, which is a nonlinear delay differential model, is used. The purpose of this …

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Prediction Of Emissions And Exhaust Temperature For Direct Injection Diesel Engine With Emulsified Fuel Using Ann, Görkem Kökkülünk, Erhan Akdoğan, Vezi̇r Ayhan Jan 2013

Prediction Of Emissions And Exhaust Temperature For Direct Injection Diesel Engine With Emulsified Fuel Using Ann, Görkem Kökkülünk, Erhan Akdoğan, Vezi̇r Ayhan

Turkish Journal of Electrical Engineering and Computer Sciences

Exhaust gases have many effects on human beings and the environment. Therefore, they must be kept under control. The International Convention for the Prevention of Pollution from Ships (MARPOL), which is concerned with the prevention of marine pollution, limits the emissions according to the regulations. In Emission Control Area (ECA) regions, which are determined by MARPOL as ECAs, the emission rates should be controlled. Direct injection (DI) diesel engines are commonly used as a propulsion system on ships. The prediction and control of diesel engine emission rates is not an easy task in real time. Therefore, in this study, an …

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Power Efficient Linear Transmitters Using Sigma-Delta Modulation With Switching Amplifiers, Tayfun Nesimoglu Jan 2013

Power Efficient Linear Transmitters Using Sigma-Delta Modulation With Switching Amplifiers, Tayfun Nesimoglu

Turkish Journal of Electrical Engineering and Computer Sciences

In conventional envelope elimination and restoration transmitters, the envelope information of the carrier is reconstructed by modulating the supply voltage of the switching amplifier. In this paper, it is shown that the supply voltage modulation introduces nonlinearity and reduces the average power efficiency of the transmitter. Here, novel transmitter architectures using sigma-delta--modulated carrier signals are proposed to overcome these shortcomings. The proposed architecture's and conventional envelope elimination and restoration transmitter's linearity and efficiency performances are compared at various oversampling rates and signal bandwidths. It is demonstrated that the proposed architectures may provide better linearity and efficiency than conventional envelope elimination …

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Adaptive Control Of A Time-Varying Rotary Servo System Using A Fuzzy Model Reference Learning Controller With Variable Adaptation Gain, Ömer Aydoğdu, Özdemi̇r Alkan Jan 2013

Adaptive Control Of A Time-Varying Rotary Servo System Using A Fuzzy Model Reference Learning Controller With Variable Adaptation Gain, Ömer Aydoğdu, Özdemi̇r Alkan

Turkish Journal of Electrical Engineering and Computer Sciences

The constant parameters in a conventional fuzzy controller lead to a poor performance for time-varying systems. In this study, a fuzzy model reference learning controller (FMRLC) with a newly defined variable adaptation gain is designed and implemented in the adaptive fuzzy control of a time-varying rotary servo (TVRS) system. In the design of the FMRLC, a knowledge-base modification algorithm with variable adaptation gain is used instead of a fuzzy relation table. Hence, it is provided that the learning and adaptation mechanism continuously updates the knowledge base of the adaptive fuzzy controller against any parameter variations, such as changing loads. By …

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Optimized Operation And Maintenance Costs To Improve System Reliability By Decreasing The Failure Rate Of Distribution Lines, Hamed Hashemi Dezaki, Seyed Hossein Hosseinian, Hossein Askarian Abyaneh, Seyed Mohammad Mousavi Agah Jan 2013

Optimized Operation And Maintenance Costs To Improve System Reliability By Decreasing The Failure Rate Of Distribution Lines, Hamed Hashemi Dezaki, Seyed Hossein Hosseinian, Hossein Askarian Abyaneh, Seyed Mohammad Mousavi Agah

Turkish Journal of Electrical Engineering and Computer Sciences

Improving distribution system reliability has received a great deal of attention in recent years. Because of the limitation in expected budgets, it is desirable to determine the most efficient strategy to improve system reliability. This paper proposes a novel method to determine the optimized operation and maintenance costs in order to decrease the failure of system components. The proposed objective function includes the average system frequency interruption index (ASIFI) value. To achieve the best strategy to decrease failures of system components, it is necessary to find the minimum value of the objective function, considering the constraints of operation and maintenance …

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A Low-Voltage And Low-Power Sinh-Domain Universal Biquadratic Filter For Low-Frequency Applications, Farooq Khanday, Nisar Shah Jan 2013

A Low-Voltage And Low-Power Sinh-Domain Universal Biquadratic Filter For Low-Frequency Applications, Farooq Khanday, Nisar Shah

Turkish Journal of Electrical Engineering and Computer Sciences

Sinh-domain CMOS filters have favorable properties, such as a wide dynamic range at low supply voltage, compactness, linearity, and low power consumption. These properties are becoming increasingly important for biomedical applications that require extremely low-power dissipation and neuromorphic circuits that attempt to reproduce the biophysics of biological neurons and synapses. In this paper, a low-voltage sinh-domain universal biquadratic filter circuit is introduced. The circuit, aside from permitting the independent adjustment of pole frequency (\omega_0) and the quality factor (Q), is free from matching conditions, capable of absorbing the shunt parasitic capacitances, amenable for monolithic integration, and composed of merely a …

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Control Of Diesel Engines Mounted On Vehicles In Mobile Cranes Via Can Bus, Muci̇z Özcan, Hi̇dayet Günay Jan 2013

Control Of Diesel Engines Mounted On Vehicles In Mobile Cranes Via Can Bus, Muci̇z Özcan, Hi̇dayet Günay

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the aim was to lift loads that required more force using the infrastructure of existing vehicles. To this end, a truck-mounted diesel engine was selected to be used in mobile crane applications. A control system was designed and implemented to obtain the appropriate hydraulic force by accessing the diesel engine with a controller area network bus via an electronic control unit (ECU). For this purpose, hydraulic pumps to be used to operate the crane were mounted on the selected mobile diesel engine with an ECU. Firms that manufacture cranes in the world produce cranes with infrastructure. This …

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Design Of Information Retrieval Experiments: The Sufficient Topic Set Size For Providing An Adequate Level Of Confidence, Beki̇r Taner Di̇nçer Jan 2013

Design Of Information Retrieval Experiments: The Sufficient Topic Set Size For Providing An Adequate Level Of Confidence, Beki̇r Taner Di̇nçer

Turkish Journal of Electrical Engineering and Computer Sciences

In the current design of information retrieval (IR) experiments, a sample of 50 topics is generally agreed to be sufficient in size to perform dependable system evaluations. This article presents the detailed and formal explanation of how the second fundamental theorem of probability, the central limit theorem, can be used for the estimation of the sufficient size of a topic sample. The research performed in this article, using past Text Retrieval Conference data, reveals that, on average, 50 topics will be sufficient to provide a confidence level at or above 95% if the null hypothesis of an equal population mean …

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A Novel Dynamic Bandwidth Selection Method For Thinning Noisy Point Clouds, Mehmet Öztürk, Zeynep Hasirci Jan 2013

A Novel Dynamic Bandwidth Selection Method For Thinning Noisy Point Clouds, Mehmet Öztürk, Zeynep Hasirci

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a dynamic bandwidth selection method for thinning noisy point clouds into curves. Due to the nonhomogeneous distribution of noise or varying curvature of the data, the thinning procedure requires a dynamically adjusted bandwidth along the curve. On the other hand, the selected local region must be sorted along a suitable direction vector for local curve fitting purposes. The contribution of this paper to the field is 2-folded: first, a normalized eigenvalue analysis-based method is used to determine the best local bandwidth. The second task is getting a good regression line of the local region for …

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Stopping Spam With Sending Session Verification, Ahmet Baran Jan 2013

Stopping Spam With Sending Session Verification, Ahmet Baran

Turkish Journal of Electrical Engineering and Computer Sciences

Spam has become one of the most significant problems for Internet communication and users today. The traditional filtering methods and signature-based spam blocking systems that have come into prominence recently fall short, as statistics demonstrate that spam further mounts up day after day. In this study, a new method is recommended to block spam mails. In this recommended method, a mail sending session is verified during mail envelope communication by adding small attachments to the simple mail transfer protocol, so spam mails can be blocked before leaving the sender domain or relay machine. Additionally, hijacked user accounts are able to …

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Optimal Placement And Sizing Of Distributed Generations In Distribution Systems For Minimizing Losses And Thd_V Using Evolutionary Programming, Aida Fazliana Abdul Kadir, Azah Mohamed, Hussain Shareef, Mohd Zamri Che Wanik Jan 2013

Optimal Placement And Sizing Of Distributed Generations In Distribution Systems For Minimizing Losses And Thd_V Using Evolutionary Programming, Aida Fazliana Abdul Kadir, Azah Mohamed, Hussain Shareef, Mohd Zamri Che Wanik

Turkish Journal of Electrical Engineering and Computer Sciences

Growing concerns over environmental impacts, improvement of the overall network conditions, and rebate programs offered by governments have led to an increase in the number of distributed generation (DG) units in commercial and domestic electric power production. However, a large number of DG units in a distribution system may sometimes contribute to high levels of harmonic distortion, even though the emission levels of the individual DG units comply with the harmonic standards. It is known that the nonoptimal size and nonoptimal placement of DG units may lead to high power losses, bad voltage profiles, and harmonic propagations. Therefore, this paper …

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Ssr Mitigation With Sssc Thanks To Fuzzy Control, Seyed Mohammad Hassan Hosseini, Hadi Samadzadeh, Javad Olamaei, Murtaza Farsadi Jan 2013

Ssr Mitigation With Sssc Thanks To Fuzzy Control, Seyed Mohammad Hassan Hosseini, Hadi Samadzadeh, Javad Olamaei, Murtaza Farsadi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with the capability of a static synchronous series compensator (SSSC) to attenuate the subsynchronous resonance (SSR). Two well-known controllers are designed, namely a conventional damping controller (CDC) and fuzzy logic damping controller (FLDC). These 2 damping controllers are added to a main control loop of a SSSC operating as a SSR damping controller. It should be noted that, to optimize the parameters of the CDC, a versatile optimization technique is implemented, namely particle swarm optimization (PSO). A comprehensive comparison between the 2 control methods is carried out for different operational conditions. To observe the superior performance of …

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