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2015

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Articles 7291 - 7320 of 7510

Full-Text Articles in Engineering

Temporal Logic Extension For Self-Referring, Nonexistence, Multiple Recurrence, And Anterior Past Events, Şadi̇ Evren Şeker Jan 2015

Temporal Logic Extension For Self-Referring, Nonexistence, Multiple Recurrence, And Anterior Past Events, Şadi̇ Evren Şeker

Turkish Journal of Electrical Engineering and Computer Sciences

This study focuses on the possible extensions of current temporal logics. In this study, 4 extensions are proposed: self-referring events, nonexisting events, multiple recurrence of events, and an improvement on anterior past events. Each of these extensions is on a different level of temporal logics. The main motivation behind the extensions is the temporal analysis of Turkish. Similar to temporal logic studies built on other natural languages, like French, Ukrainian, Italian, Korean, English, or Romanian, this is the first time that the Turkish language has been deeply questioned in the sense of computable temporal logic using the view of a …

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Discrete-Time Modeling Of Hamiltonian Systems, Yaprak Yalçin, Leyla Gören Sümer, Salman Kurtulan Jan 2015

Discrete-Time Modeling Of Hamiltonian Systems, Yaprak Yalçin, Leyla Gören Sümer, Salman Kurtulan

Turkish Journal of Electrical Engineering and Computer Sciences

The problem of discrete-time modeling of the lumped-parameter Hamiltonian systems is considered for engineering applications. Hence, a novel gradient-based method is presented, exploiting the discrete gradient concept and the forward Euler discretization under the assumption of the continuous Hamiltonian model is known. It is proven that the proposed discrete-time model structure defines a symplectic difference system and has the energy-conserving property under some conditions. In order to provide alternate discrete-time models, 3 different discrete-gradient definitions are given. The proposed models are convenient for the design of sampled-data controllers. All of the models are considered for several well-known Hamiltonian systems and …

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Control Of Oxygen Excess Ratio In A Pem Fuel Cell System Using High-Order Sliding-Mode Controller And Observer, Seyed Mehdi Rakhtala, Abolfazl Ranjbar Noei, Reza Ghaderi, Elio Usai Jan 2015

Control Of Oxygen Excess Ratio In A Pem Fuel Cell System Using High-Order Sliding-Mode Controller And Observer, Seyed Mehdi Rakhtala, Abolfazl Ranjbar Noei, Reza Ghaderi, Elio Usai

Turkish Journal of Electrical Engineering and Computer Sciences

The main objective of this manuscript is to design a high-order sliding-mode observer to provide finite time estimation of unmeasurable states (x_4: oxygen mass, x_5: nitrogen mass) together with the oxygen excess ratio (ratio of the input oxygen flow to the reacted oxygen flow in the cathode). This is done by applying second-order sliding modes through either super twisting or suboptimal controllers to control the proton exchange membrane fuel cell's breathing. The estimated oxygen excess ratio is controlled in a closed-loop system using 2 distinct sliding-mode approaches: a cascaded super twisting controller and a single-loop suboptimal structure. Simulation results are …

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A Robust Algorithm Based On A Failure-Sensitive Matrix For Fault Diagnosis Of Power Systems: An Application On Power Transformers, Yunus Bi̇çen, Faruk Aras Jan 2015

A Robust Algorithm Based On A Failure-Sensitive Matrix For Fault Diagnosis Of Power Systems: An Application On Power Transformers, Yunus Bi̇çen, Faruk Aras

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a robust algorithm for fault diagnosis of power system equipment based on a failure-sensitive matrix (FSM) is presented. The FSM is a dynamic matrix structure updated by multiple measurements (online) and test results (offline) on the systems. The algorithm uses many different artificial intelligence and expert system methods for adaptively detecting the location of faults, emerging failures, and causes of failures. In this algorithm, all data obtained from the power transformer, which have various nonlinear input and output parameters, are processed using the parallel matrix structure of the FSM to reach a global solution quickly. The parameters …

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Enhancing Sliding Mode Control With Proportional Feedback And Feedforward: An Experimental Investigation On Speed Sensorless Control Of Pm Dc Motor Drives, Mehmet Dal Jan 2015

Enhancing Sliding Mode Control With Proportional Feedback And Feedforward: An Experimental Investigation On Speed Sensorless Control Of Pm Dc Motor Drives, Mehmet Dal

Turkish Journal of Electrical Engineering and Computer Sciences

This paper investigates the enhancement of sliding mode control (SMC) with the combined use of feedforward torque compensation and proportional error feedback control. The proposed enhancement is adapted to the control of permanent magnet (PM) DC motor drives by synthesis of the equivalent control equation augmented as proportional feedback and feedforward terms. A novel sliding function, introduced by utilizing the estimated load torque and the estimated rotor current, is examined and compared with another known sliding function obtained by nonideal differentiation of the estimated rotor speed. The significance of the proposed enhancements to SMC consists of the elimination of disturbance, …

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Mersenne Twister-Based Rfid Authentication Protocol, Mehmet Hi̇lal Özcanhan, Gökhan Dalkiliç Jan 2015

Mersenne Twister-Based Rfid Authentication Protocol, Mehmet Hi̇lal Özcanhan, Gökhan Dalkiliç

Turkish Journal of Electrical Engineering and Computer Sciences

This work presents an ultra-lightweight, cryptographic, mutual authentication protocol for radio-frequency identification (RFID) tags. The proposed scheme is more secure than its predecessors. The vulnerabilities of previous schemes based on triangular functions and rotation have been demonstrated in traditional and rotational cryptanalysis. In this paper, we summarize the successful attacks on previous schemes and demonstrate further attacks on 3 recent ultra-lightweight protocols. Next, we present a proposal that resists all of the known passive attacks. The proposal obeys the properties and rules of addition-rotation-XOR with constants systems. The proposed scheme inserts parts of advanced encryption standard S-boxes into the temperings …

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Dynamic Modeling Of Modular Fuel Cell For Maximum Power Point Tracking And Torque Ripple Reduction In Direct Torque Control Of Induction Motor, Majid Valizadeh, Mohammad Reza Feyzi, Ebrahim Babaei, Mehran Sabahi Jan 2015

Dynamic Modeling Of Modular Fuel Cell For Maximum Power Point Tracking And Torque Ripple Reduction In Direct Torque Control Of Induction Motor, Majid Valizadeh, Mohammad Reza Feyzi, Ebrahim Babaei, Mehran Sabahi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a comprehensive dynamic model of a proton exchange membrane fuel cell (FC) based on the electrical empirical model. The presented model is useful for online control as well as having suitable accuracy. FC stacks produce a DC voltage with a ratio of 2:1 in output from no-load to full-load. In vehicles that are equipped with FCs, the output voltage of the FC is drastically changed because the power and torque of the vehicle change with the driving cycle. In order to improve the performance of the direct torque control of induction motors, the modular structure of a …

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A New Heuristic Method To Solve Unit Commitment By Using A Time-Variant Acceleration Coefficients Particle Swarm Optimization Algorithm, Arsalan Najafi, Mohsen Farshad, Hamid Falaghi Jan 2015

A New Heuristic Method To Solve Unit Commitment By Using A Time-Variant Acceleration Coefficients Particle Swarm Optimization Algorithm, Arsalan Najafi, Mohsen Farshad, Hamid Falaghi

Turkish Journal of Electrical Engineering and Computer Sciences

Unit commitment is one of the most important problems in power system operation. Because of the large amount of parameters and constraints, it contains a high level of complexity. In this paper a new method based on a time-variant acceleration coefficients particle swarm optimization algorithm has been proposed to solve the unit commitment problem. Integer coding (for satisfying minimum up/down constraints) and binary coding (for satisfying spinning reserve constraint) have been utilized in the proposed method. Simulations in the different cases have been done with different sizes. Numerical results have shown the superiority and better convergence of the proposed method …

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Bandwidth Extension Of Narrowband Speech In Log Spectra Domain Using Neural Network, Sara Pourmohammadi, Mansour Vali, Mohsen Ghadyani Jan 2015

Bandwidth Extension Of Narrowband Speech In Log Spectra Domain Using Neural Network, Sara Pourmohammadi, Mansour Vali, Mohsen Ghadyani

Turkish Journal of Electrical Engineering and Computer Sciences

In recent years, there have been significant advances in communication technology, but speech signals still suffer from low perceived quality caused by bandwidth limitations of telephone networks. The bandwidth extension (BWE) approach adds high-frequency components of the speech signal to band-limited telephone speech and increases speech perception significantly. In this work, we develop a new method for representation of vocal tract filter coefficients using log of filter bank energy (LFBE) parameters as an alternative for mel-frequency cepstral coefficients (MFCCs). This approach is based on a strong correlation between the spectral components of low- and high-band spectrums. Furthermore, the performances of …

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Continuous-Time Hopfield Neural Network-Based Optimized Solution To 2-Channel Allocation Problem, Zekeri̇ya Uykan Jan 2015

Continuous-Time Hopfield Neural Network-Based Optimized Solution To 2-Channel Allocation Problem, Zekeri̇ya Uykan

Turkish Journal of Electrical Engineering and Computer Sciences

The channel allocation problem in cellular radio systems is NP-complete, and thus its general solution is not known for even the 2-channel case. It is well known that the link gain system matrix (or received-signal power system matrix) of the radio network is (and may be highly) asymmetric, and that as the Hopfield neural network is applied to optimization problems, its weight matrix should be symmetric. The main contribution of this paper is as follows: turning the channel allocation problem into a maxCut graph partitioning problem, we propose a simple and effective continuous-time Hopfield neural network-based solution by determining its …

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Improving The Performance Of Primal--Dual Interior-Point Method In Inverse Conductivity Problems, Ashkan Javaherian, Amir Movafeghi, Reza Faghihi, Effat Yahaghi Jan 2015

Improving The Performance Of Primal--Dual Interior-Point Method In Inverse Conductivity Problems, Ashkan Javaherian, Amir Movafeghi, Reza Faghihi, Effat Yahaghi

Turkish Journal of Electrical Engineering and Computer Sciences

This study improves the performance of primal--dual interior-point method in inverse conductivity problems via replacing the conventional, complicatedly calculated scalar regularization parameter with a diagonal matrix termed ``multi-regularization parameter matrix'' here. The solution of the PD--IPM depends considerably on the choice of the regularization parameter. Calculation of the optimal regularization parameter, which yields the most accurate solution, is not simple due to the long iterative nature of the algorithm. The objective optimization, which is implemented by minimizing error in the solutions over an extensive range of the regularization parameters, yields the most accurate solution that can be achieved, although this …

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A Particle Swarm Optimization-Based Approach To Achieve Optimal Design And Operation Strategy Of Standalone Hybrid Energy Systems, Mahram Ghazvini, Ali Abbaspour Tehrani Fard, Mahmud Fotuhi Firuzabad Jan 2015

A Particle Swarm Optimization-Based Approach To Achieve Optimal Design And Operation Strategy Of Standalone Hybrid Energy Systems, Mahram Ghazvini, Ali Abbaspour Tehrani Fard, Mahmud Fotuhi Firuzabad

Turkish Journal of Electrical Engineering and Computer Sciences

As a cost-effective and reliable alternative to supply remote areas, standalone hybrid energy systems (HESs) are recently under investigation to address various concerns associated with technical, financial, and environmental issues. This paper presents a comprehensive algorithm that can simultaneously optimize the component size, operation strategy, and slope of the photovoltaic panels of a standalone HES using an improved variant of particle swarm optimization (PSO), designated as the passive congregation PSO. A new operation strategy is proposed based on the set points of the control system. The optimization algorithm determines the optimal values of the set points to efficiently optimize the …

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Tracking Control Of Elastic Joint Parallel Robots Via State-Dependent Riccati Equation, Si̇nan Kiliçaslan Jan 2015

Tracking Control Of Elastic Joint Parallel Robots Via State-Dependent Riccati Equation, Si̇nan Kiliçaslan

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a methodology for the tracking control of parallel robots having elastic joints based on the state-dependent Riccati equation is developed. Structural stiffness and damping characteristics of the joints are modeled as torsional springs and dampers, respectively. First an open-tree system is obtained by cutting some joints of the parallel robot open and its dynamic equations are written. Closed loops are then represented as constraint equations. The first and second derivatives of dependent (unactuated) joint variables are expressed in terms of independent (actuated) joint variables by making use of the constraint equations. Taking the independent joint variables, the …

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Short-Term Load Forecasting Without Meteorological Data Using Ai-Based Structures, İdi̇l Işikli Esener, Tolga Yüksel, Mehmet Kurban Jan 2015

Short-Term Load Forecasting Without Meteorological Data Using Ai-Based Structures, İdi̇l Işikli Esener, Tolga Yüksel, Mehmet Kurban

Turkish Journal of Electrical Engineering and Computer Sciences

STLF is used in making decisions about economical power generation capacity, fuel purchasing, safety assessment, and power system planning in order to have economical power conditions. In this study, Turkey's 24-hour-ahead load forecasting without meteorological data is studied. ANN, wavelet transform and ANN, wavelet transform and RBF NN, and EMD and RBF NN structures are used in STLF procedures. Local holidays' historical load data are changed into data with normal day characteristics, and the estimation results of these days are not included in error computation. To obtain more accurate results, a regulation on forecasted loads is proposed. Regulated and unregulated …

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A New Systematic And Flexible Method For Developing Hierarchical Decision-Making Models, Ulaş Beldek, Mehmet Kemal Leblebi̇ci̇oğlu Jan 2015

A New Systematic And Flexible Method For Developing Hierarchical Decision-Making Models, Ulaş Beldek, Mehmet Kemal Leblebi̇ci̇oğlu

Turkish Journal of Electrical Engineering and Computer Sciences

The common practice in multilevel decision-making (DM) systems is to achieve the final decision by going through a finite number of DM levels. In this study, a new multilevel DM model is proposed. This model is called the hierarchical DM (HDM) model and it is supposed to provide a flexible way of interaction and information flow between the consecutive levels that allows policy changes in DM procedures if necessary. In the model, in the early levels, there are primary agents that perform DM tasks. As the levels increase, the information associated with these agents is combined through suitable processes and …

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The Detailed Analysis Of Rate Equation Roots Of Bh-Laser Diode Using Volterra Series, Remzi̇ Yildirim, Ahmet Karaarslan Jan 2015

The Detailed Analysis Of Rate Equation Roots Of Bh-Laser Diode Using Volterra Series, Remzi̇ Yildirim, Ahmet Karaarslan

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the rate equation analysis of a BH-laser diode was performed for output carrier density (N_o) using the zero-degree solution of the Volterra series. The carrier rate equation of the laser diode was analyzed in terms of input carrier density (N_i) and output carrier density modeling (N_i-N_o), with respect to the DC current (I_o). The polynomial root, which is obtained from the zero-degree solution (N_o) and limit values of I_o, was found. For the linear operation of the laser diode, the range of I_o current was also determined using a linearization approach and the maximum value of N_o.

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Demand Response In The Day-Ahead Operation Of An Isolated Microgrid In The Presence Of Uncertainty Of Wind Power, Javad Olamaei, Saleh Ashouri Jan 2015

Demand Response In The Day-Ahead Operation Of An Isolated Microgrid In The Presence Of Uncertainty Of Wind Power, Javad Olamaei, Saleh Ashouri

Turkish Journal of Electrical Engineering and Computer Sciences

This paper explores the utilization of demand response in the day-ahead operation of an isolated microgrid in the presence of wind units. The operation of the network with high penetration wind units (i.e. uncertainty of wind units) is modeled as a unit commitment problem. In addition, electrical power storage is modeled in a daily power curve to decrease the effect of uncertainty in the wind units. Due to avoiding large-scale complexities and the deeper study effect of demand-side management on operations, the considered network is regarded as an isolated microgrid. The demand-side management is studied as demand shifting. The simulation …

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Control Of Soil Moisture With Radio Frequency In A Photovoltaic-Powered Drip Irrigation System, Mahi̇r Dursun, Semi̇h Özden Jan 2015

Control Of Soil Moisture With Radio Frequency In A Photovoltaic-Powered Drip Irrigation System, Mahi̇r Dursun, Semi̇h Özden

Turkish Journal of Electrical Engineering and Computer Sciences

Solar-powered irrigation systems are becoming increasingly widespread. However, the initial setup costs of these systems are very high. To reduce these costs, both the energy usage and the prevention of losses from irrigation systems are very important. In this study, a drip irrigation control system of 1000 dwarf cherry trees was controlled using soil moisture sensors in order to prevent excessive water consumption and energy losses in a solar-powered irrigation system. The control system comprises units that are energized with solar panels, and the flow of information is implemented via radio frequency. Thus, by removing the cables that create difficulties …

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Quality Of Service Assessment: A Case Study On Performance Benchmarking Of Cellular Network Operators In Turkey, Rana Kadioğlu, Yaser Dalveren, Ali̇ Kara Jan 2015

Quality Of Service Assessment: A Case Study On Performance Benchmarking Of Cellular Network Operators In Turkey, Rana Kadioğlu, Yaser Dalveren, Ali̇ Kara

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents findings on performance benchmarking of cellular network operators in Turkey. Benchmarking is based on measurements of standard key performance indicators (KPIs) in one of the metropolitan cities of Turkey, Ankara. Performance benchmarking is formulated by incorporating customer perception by conducting surveys on how important KPIs are from the user's point of view. KPIs are measured, with standard test equipment, by drive test method on specified routes. According to the performance benchmarking results, the GSM and UMTS network operators achieving the best performance were determined in Ankara. Speech qualities of network operators, as the most popular service, were …

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Efficient Id-Based Authentication And Key Agreement Protocols For The Session Initiation Protocol, Haci Hakan Kilinç, Yolguly Allaberdiyev, Tuğrul Yanik, Serdar Süer Erdem Jan 2015

Efficient Id-Based Authentication And Key Agreement Protocols For The Session Initiation Protocol, Haci Hakan Kilinç, Yolguly Allaberdiyev, Tuğrul Yanik, Serdar Süer Erdem

Turkish Journal of Electrical Engineering and Computer Sciences

In a widely deployed VoIP system tens of thousands of clients compete for the SIP proxy server's authentication service. SIP protocol implementations have to meet certain QoS and security requirements. In this study new ID-based protocols are proposed for the SIP authentication and key agreement protocols. These protocols minimize the use of expensive pairing functions but still resist notable attacks. The security of the proposed protocols are analyzed and demonstrated with security proofs based on the BJM security model. Finally, the performance overhead of the proposed protocols are compared to ID-based SIP authentication and key agreement protocols given in the …

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A New Feature Selection Model Based On Id3 And Bees Algorithm For Intrusion Detection System, Adel Sabry Eesa, Zeynep Orman, Adnan Mohsin Abdulazeez Brifcani Jan 2015

A New Feature Selection Model Based On Id3 And Bees Algorithm For Intrusion Detection System, Adel Sabry Eesa, Zeynep Orman, Adnan Mohsin Abdulazeez Brifcani

Turkish Journal of Electrical Engineering and Computer Sciences

Intrusion detection systems (IDSs) have become a necessary component of computers and information security framework. IDSs commonly deal with a large amount of data traffic and these data may contain redundant and unimportant features. Choosing the best quality of features that represent all of the data and exclude the redundant features is a crucial topic in IDSs. In this paper, a new combination approach based on the ID3 algorithm and the bees algorithm (BA) is proposed to select the optimal subset of features for an IDS. The BA is used to generate a subset of features, and the ID3 algorithm …

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Type Iii Compensated Voltage Mode Line Feedforward Synchronously Rectified Boost Converter For Driving Class D Audio H-Bridge To Deliver 7 W Peak Power Into An 8 Omega Speaker, Yavuz Kiliç Jan 2015

Type Iii Compensated Voltage Mode Line Feedforward Synchronously Rectified Boost Converter For Driving Class D Audio H-Bridge To Deliver 7 W Peak Power Into An 8 Omega Speaker, Yavuz Kiliç

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a circuit topology for a synchronously rectified boost converter aimed to act as a power supply for a Class D H-bridge that would deliver up to 7 W peak power into an 8 Omega speaker is presented. The design is implemented in a submicron BCD process technology. Some of the challenges in this design are as follows. The first challenge was to optimise the design such that it would not cause on-chip power dissipation levels that would go beyond acceptable levels for Wafer Level Chip Scale Package (WLCSP), which is a commonly used package for space constrained …

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Model-Based Test Case Prioritization Using Cluster Analysis: A Soft-Computing Approach, Ni̇da Gökçe, Fevzi̇ Belli̇, Mübari̇z Emi̇nli̇, Beki̇r Taner Di̇nçer Jan 2015

Model-Based Test Case Prioritization Using Cluster Analysis: A Soft-Computing Approach, Ni̇da Gökçe, Fevzi̇ Belli̇, Mübari̇z Emi̇nli̇, Beki̇r Taner Di̇nçer

Turkish Journal of Electrical Engineering and Computer Sciences

Model-based testing is related to the particular relevant features of the software under test (SUT) and its environment. Real-life systems often require a large number of tests, which cannot exhaustively be run due to time and cost constraints. Thus, it is necessary to prioritize the test cases in accordance with their importance as the tester perceives it, usually given by several attributes of relevant events entailed. Based on event-oriented graph models, this paper proposes an approach to ranking test cases in accordance with their preference degrees. For forming preference groups, events are clustered using an unsupervised neural network and fuzzy …

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Predictive Control Of A Constrained Pressure And Level System, Erkan Kaplanoğlu, Taner Arsan, Hüseyi̇n Selçuk Varol Jan 2015

Predictive Control Of A Constrained Pressure And Level System, Erkan Kaplanoğlu, Taner Arsan, Hüseyi̇n Selçuk Varol

Turkish Journal of Electrical Engineering and Computer Sciences

The focus of this paper is the implementation of a constrained predictive control algorithm implemented in Multi-Parametric Toolbox (MPT), which is a free MATLAB toolbox for design, analysis, and implementation of controllers for constrained linear, nonlinear, and hybrid systems. In general, MPT is used for modeling systems offline. The novelty of this study is that real-time mode MPT is used in process control. We also combined the Model Predictive Control Toolbox with MPT. This novel controller is considered a real-time controller of level-pressure systems. In this study, a special type of model predictive control algorithm, the constrained continuous-time generalized control, …

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A New Hysteresis Band Current Control Technique For A Shunt Active Filter, Murat Kale, Engi̇n Özdemi̇r Jan 2015

A New Hysteresis Band Current Control Technique For A Shunt Active Filter, Murat Kale, Engi̇n Özdemi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a hysteresis band (HB) current control technique to reduce the power losses in a shunt active filter. During a switching period in the zero-crossing region, the inverter output current flows through a transistor. By changing the direction, it flows through the free-wheeling diode of the same switch in an inverter leg, or vice versa. The shunt active filter current typically has 6 zero-crossing regions during a fundamental frequency cycle. This paper presents a HB current control technique where there is not any switching in these 6 zero-crossing regions per period, which results in reducing the power losses. …

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Approximations Of Higher-Order Fractional Differentiators And Integrators Using Indirect Discretization, Richa Yadav, Maneesha Gupta Jan 2015

Approximations Of Higher-Order Fractional Differentiators And Integrators Using Indirect Discretization, Richa Yadav, Maneesha Gupta

Turkish Journal of Electrical Engineering and Computer Sciences

This paper describes new approximations of fractional order integrators (FOIs) and fractional order differentiators (FODs) by using a continued fraction expansion-based indirect discretization scheme. Different tenth-order fractional blocks have been derived by applying three different s-to-z transforms described earlier by Al-Alaoui, namely new two-segment, four-segment, and new optimized four-segment operators. A new addition has been done in the new optimized four-segment operator by modifying it by the zero reflection method. All proposed half (s$^{\pm 1/2})$ and one-fourth (s$^{\pm 1/4})$ differentiator and integrator models fulfill the stability criterion. The tenth-order fractional differ-integrators (s$^{\pm \alpha })$ based on the modified new optimized …

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Design And Control Of A Visual Servomechanism For Automating Corneal Cross-Linking Treatment In Keratoconus Patients, Onurcan Şahi̇n, Erdi̇nç Altuğ Jan 2015

Design And Control Of A Visual Servomechanism For Automating Corneal Cross-Linking Treatment In Keratoconus Patients, Onurcan Şahi̇n, Erdi̇nç Altuğ

Turkish Journal of Electrical Engineering and Computer Sciences

A novel mechatronic system designed for automated corneal cross-linking (CCL) treatment in keratoconus patients is introduced. Keratoconus is a serious illness that if not treated may cause serious distortion of vision. Currently, the CCL operation, which is the most promising treatment of this disease, is performed manually. The automated system developed is the first of its kind to automate the treatment with visual feedback, and it aims to increase the efficiency in treatment and to eliminate any potential side effects and risks of the treatment. To track the eye of the patient, the system consists of a camera, an image …

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Performance Of Support Vector Regression Machines On Determining The Magnetic Characteristics Of The E-Core Transverse Flux Machine, Çi̇ğdem Gündoğan Türker, Feri̇ha Erfan Kuyumcu, Nurhan Türker Tokan Jan 2015

Performance Of Support Vector Regression Machines On Determining The Magnetic Characteristics Of The E-Core Transverse Flux Machine, Çi̇ğdem Gündoğan Türker, Feri̇ha Erfan Kuyumcu, Nurhan Türker Tokan

Turkish Journal of Electrical Engineering and Computer Sciences

The E-core transverse flux machine (ETFM) has major advantages with its different and unique structure in conventional electrical machines. It is a combination of transverse flux and reluctance principle. In this work, support vector regression machines (SVRMs) are used to obtain the magnetic characteristic parameters of the ETFM for the first time and it is compared with its artificial neural network model. The data for the training and testing of the SVRMs are obtained from experimental measurements. It is proven that SVRMs can conveniently be used in the modeling of the magnetic behaviors of highly nonlinear ETFM with better accuracy …

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Dwmt Transceiver Equalization Using Overlap Fde For Downlink Adsl, Arsla Khan, Sobia Baig, Tabassum Nawaz Jan 2015

Dwmt Transceiver Equalization Using Overlap Fde For Downlink Adsl, Arsla Khan, Sobia Baig, Tabassum Nawaz

Turkish Journal of Electrical Engineering and Computer Sciences

Discrete wavelet multitone (DWMT) modulation is a wavelet transform based technique implemented using perfect reconstruction filter banks. It has been recently proposed for various wireline channels such as digital subscriber loops (DSLs) as a solution to the problems posed by a discrete multitone (DMT) transceiver including interblock interference (IBI) and lower spectral efficiency due to the employment of a cyclic prefix (CP) in the guard interval (GI) for DMT symbols. The greater side lobe attenuation offered by wavelet filter banks results in improved spectral containment and lower IBI in DWMT transceivers. However, no standard equalization technique exists for a DWMT …

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Using The Finite Element Method To Calculate Parameters For A Detailed Model Of Transformer Winding For Partial Discharge Research, Seyed Mohammad Hassan Hosseini, Seyed Mohsen Enjavi Madar, Mehdi Vakilian Jan 2015

Using The Finite Element Method To Calculate Parameters For A Detailed Model Of Transformer Winding For Partial Discharge Research, Seyed Mohammad Hassan Hosseini, Seyed Mohsen Enjavi Madar, Mehdi Vakilian

Turkish Journal of Electrical Engineering and Computer Sciences

Power transformers are considered to be one of the most essential and costly pieces of equipment in a power system. Identifying insulation faults in the shortest possible time prevents the occurrence of irreparable damage. Partial discharge (PD) is one of the most significant insulation faults. The first step in the study of PD is the precise modeling of transformer winding at high frequencies. In this paper, the finite element method is used to calculate the parameters for a detailed model of transformer winding. For this reason, a detailed model of transformer winding and the analytic formulations are first presented for …

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