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Full-Text Articles in Physical Sciences and Mathematics

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 …


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 …


An Intelligence-Based Islanding Detection Method Using Dwt And Ann, Mehrdad Heidari, Ghodratollah Seifossadat, Morteza Razaz Jan 2015

An Intelligence-Based Islanding Detection Method Using Dwt And Ann, Mehrdad Heidari, Ghodratollah Seifossadat, Morteza Razaz

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new method based on artificial neural network (ANN) and discrete wavelet transform (DWT) is proposed for electrical islanding detection. Transient signals produced during an event are used in the proposed method. ANN is trained to classify the transient events as islanding and nonislanding. The required features for classifying are extracted through DWT of voltage and current transient signals. The proposed method is then simulated on a medium voltage distribution system of CIGRE with 2 kinds of DGs. Results show that this method can detect electrical islands more rapidly and accurately.


Epilepsy Diagnosis Using Artificial Neural Network Learned By Pso, Nesi̇be Yalçin, Gülay Tezel, Ci̇han Karakuzu Jan 2015

Epilepsy Diagnosis Using Artificial Neural Network Learned By Pso, Nesi̇be Yalçin, Gülay Tezel, Ci̇han Karakuzu

Turkish Journal of Electrical Engineering and Computer Sciences

Electroencephalogram (EEG) is used routinely for diagnosis of diseases occurring in the brain. It is a very useful clinical tool in the classification of epileptic seizures and the diagnosis of epilepsy. In this study, epilepsy diagnosis has been investigated using EEG records. For this purpose, an artificial neural network (ANN), widely used and known as an active classification technique, is applied. The particle swarm optimization (PSO) method, which does not need gradient calculation, derivative information, or any solution of differential equations, is preferred as the training algorithm for the ANN. A PSO-based neural network (PSONN) model is diversified according to …


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 …


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 …


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.


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 …


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 …


An Accelerated And Accurate Three-Dimensional Ray Tracing Using Red-Black Tree With Facet Mining And Object Bouncing Techniques, Mohammad Jakirul Islam, Ahmed Wasif Reza, Kamarul Ariffin Noordin, Kaharudin Dimyati, Abu Sulaiman Mohammad Zahid Kausar Jan 2015

An Accelerated And Accurate Three-Dimensional Ray Tracing Using Red-Black Tree With Facet Mining And Object Bouncing Techniques, Mohammad Jakirul Islam, Ahmed Wasif Reza, Kamarul Ariffin Noordin, Kaharudin Dimyati, Abu Sulaiman Mohammad Zahid Kausar

Turkish Journal of Electrical Engineering and Computer Sciences

Recent trends show that it is a major challenge to predict the exact propagation path accurately and efficiently for three-dimensional (3D) indoor environments. Therefore, this study introduces a new 3D ray tracing algorithm based on a red-black tree with facet mining and object bouncing techniques. The red-black tree data structure offers a faster object searching operation while repeatedly performing intersection tests. On the other hand, extensive ray-facet intersection tests can be eliminated by using object and facet bouncing techniques, whereas the facet mining makes it easier to trace the transmitted ray paths accurately. The proposed method is compared with ray …


A Fault Detection, Diagnosis, And Reconfiguration Method Via Support Vector Machines}, Rana Ortaç Kabaoğlu Jan 2015

A Fault Detection, Diagnosis, And Reconfiguration Method Via Support Vector Machines}, Rana Ortaç Kabaoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a fault detection, diagnosis, and reconfiguration method based on support vector machines. This method is appropriate for certain or predetermined faults and involves a fault detection and diagnosis unit and an online controller selection type reconfiguration mechanism. In this method, when a fault is detected and diagnosed by the fault detection and diagnosis unit, a suitable controller, which has been determined via an optimization algorithm in an off-line fashion, is activated to maintain proper closed-loop performance of the system in an on-line manner. In the detection, diagnosis, and reconfiguration stages of the method, support vector classification and …


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 …


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 …


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 …


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, …


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. …


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 …


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 …


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 …


An E-Nose-Based Indoor Air Quality Monitoring System: Prediction Of Combustible And Toxic Gas Concentrations, Beki̇r Mumyakmaz, Keri̇m Karabacak Jan 2015

An E-Nose-Based Indoor Air Quality Monitoring System: Prediction Of Combustible And Toxic Gas Concentrations, Beki̇r Mumyakmaz, Keri̇m Karabacak

Turkish Journal of Electrical Engineering and Computer Sciences

A system for monitoring and predicting indoor air quality level is proposed in this paper. The system comprises a computer with a monitoring program and a sensor cell, which has an array of metal oxide gas sensors along with a temperature and humidity sensor. The gas sensors in the cell have been chosen to detect only hydrogen, methane, and carbon monoxide gases. Methane was selected as a representative for indoor combustible gases, and carbon monoxide was used to represent indoor toxic gases. Hydrogen was used as an interfering (and also combustible) gas in the study. A number of experiments were …


Moving As A Whole: Multirobot Traveling Problem Constrained By Connectivity, Yun Wang, Cheng Hu Jan 2015

Moving As A Whole: Multirobot Traveling Problem Constrained By Connectivity, Yun Wang, Cheng Hu

Turkish Journal of Electrical Engineering and Computer Sciences

A multirobot system provides many advantages over a single robot. In certain situations, robots need to maintain global connectivity while proceeding through tasks such as traveling to spots of interest in an area. This paper formulates the problem of multiple robots traveling while constrained by connectivity and analyzes the limits of increase in total traveling distance (TTD) caused by connectivity constraints. A connection condition is proposed and proven, which can be used to direct the design of solutions. Two algorithms satisfying the connection condition, connected nearest neighbor (CNN) and bold Lin-Kernighan heuristic (B-LKH), are proposed to solve this problem, which …


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 …


A Novel Adaptive Filter Design Using Lyapunov Stability Theory, Engi̇n Cemal Mengüç, Nuretti̇n Acir Jan 2015

A Novel Adaptive Filter Design Using Lyapunov Stability Theory, Engi̇n Cemal Mengüç, Nuretti̇n Acir

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new approach to design an adaptive filter using Lyapunov stability theory. The design procedure is formulated as an inequality constrained optimization problem. Lagrange multiplier theory is used as an optimization tool. Lyapunov stability theory is integrated into the constraint function to satisfy the asymptotic stability of the proposed filtering system. The tracking capability is improved by using a new analytical adaptation gain rate, which has the ability to adaptively adjust itself depending on a sequential tracking square error rate. The fast and robust convergence ability of the proposed algorithm is comparatively examined by simulation examples.


Novel Congestion Control Algorithms For A Class Of Delayed Networks, Shoorangiz Shams Shamsabad Farahani, Mohammad Reza Jahed Motlagh, Mohammad Ali Nekoui Jan 2015

Novel Congestion Control Algorithms For A Class Of Delayed Networks, Shoorangiz Shams Shamsabad Farahani, Mohammad Reza Jahed Motlagh, Mohammad Ali Nekoui

Turkish Journal of Electrical Engineering and Computer Sciences

Time delays are often instability sources and give rise to undesired oscillation and performance degradation, so it is necessary to consider delay in general congestion control schemes. In this paper, a new system model for wireless sensor networks (WSNs) is established in discrete time, subsystems including delay are presented, and the overall model is achieved by blending these subsystems. For controller synthesis, common quadratic Lyapunov functions and a new approach based on nonquadratic Lyapunov functions are utilized, and a controller is designed to stabilize each subsystem. The controller synthesis results are expressed in terms of linear matrix inequalities. Moreover, the …


Conceptual Design Of A Low-Cost Real-Time Hardware-In-The-Loop Simulator For Satellite Attitude Control System, Farhad Bayat Jan 2015

Conceptual Design Of A Low-Cost Real-Time Hardware-In-The-Loop Simulator For Satellite Attitude Control System, Farhad Bayat

Turkish Journal of Electrical Engineering and Computer Sciences

Integration of flight hardware with real-time simulation increases satellite attitude control system (ACS) reliability by providing greater test coverage through end-to-end testing in a realistic test environment. In this paper, a compound hardware and software simulator has been designed for evaluation and testing of the spacecraft ACS, placing emphasis on the real-time hardware-in-loop (RTHIL) architecture. The environment comprises both real-time control and data acquisition applications on a network of ACS hardware, the MATLAB Real-Time Workshop, and a PCI device to join the hardware and software units. Moreover, a graphical 3D simulator has been designed, enabling the designers and researchers to …


Detection Of Microcalcification In Digitized Mammograms With Multistable Cellular Neural Networks Using A New Image Enhancement Method: Automated Lesion Intensity Enhancer (Alie), Levent Ci̇vci̇k, Burak Yilmaz, Yüksel Özbay, Gani̇me Di̇lek Emli̇k Jan 2015

Detection Of Microcalcification In Digitized Mammograms With Multistable Cellular Neural Networks Using A New Image Enhancement Method: Automated Lesion Intensity Enhancer (Alie), Levent Ci̇vci̇k, Burak Yilmaz, Yüksel Özbay, Gani̇me Di̇lek Emli̇k

Turkish Journal of Electrical Engineering and Computer Sciences

Microcalcification detection is a very important issue in early diagnosis of breast cancer. Generally physicians use mammogram images for this task; however, sometimes analyzing these images become a hard task because of problems in images such as high brightness values, dense tissues, noise, and insufficient contrast level. In this paper, we present a novel technique for the task of microcalcification detection. This technique consists of three steps. The first step is focused on removing pectoral muscle and unnecessary parts from the mammogram images by using cellular neural networks (CNNs), which makes this a novel process. In the second step, we …


Forecasting The Day-Ahead Price In Electricity Balancing And Settlement Market Of Turkey By Using Artificial Neural Networks, Mehmet Ali̇ Kölmek, İsa Navruz Jan 2015

Forecasting The Day-Ahead Price In Electricity Balancing And Settlement Market Of Turkey By Using Artificial Neural Networks, Mehmet Ali̇ Kölmek, İsa Navruz

Turkish Journal of Electrical Engineering and Computer Sciences

In determination of electric energy price, most price information coming from bilateral contracts is effective, but the importance of the spot market (pool market) price cannot be ignored. Forecasting the spot market price is very crucial, especially for companies actively participating in the spot market and giving purchase and sale bids. An artificial neural network is a way frequently used for price forecasting research. In this study, simulation studies about price modeling via artificial neural networks and proper artificial neural network configurations are examined. After selection of different network topologies and parameters, attempts are made to observe network performance by …


Synthesis Of Real-Time Cloud Applications For Internet Of Things, Slawomir Bak, Radoslaw Czarnecki, Stanislaw Deniziak Jan 2015

Synthesis Of Real-Time Cloud Applications For Internet Of Things, Slawomir Bak, Radoslaw Czarnecki, Stanislaw Deniziak

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the methodology for the synthesis of real-time applications working in the ``Internet of Things'' environment. We propose the client-server architecture, where embedded systems act as smart clients and the Internet application is a server of the system. The architecture of the application conforms to the cloud computing model. Since centralized systems are prone to bottlenecks caused by accumulation of transmissions or computations, we propose the distributed architecture of the server and the methodology that constructs this architecture using Internet resources supported by a cloud provider. We assume that the function of the server is specified as a …


An Aggregate Indicator For Mobile Application Quality Assessment, Paul Pocatilu, Ion Ivan, Alin Zamfiroiu, Catalin Boja Jan 2015

An Aggregate Indicator For Mobile Application Quality Assessment, Paul Pocatilu, Ion Ivan, Alin Zamfiroiu, Catalin Boja

Turkish Journal of Electrical Engineering and Computer Sciences

The mobile applications environment has a multitude of particularities generated by the complex system of devices, hardware, and software profiles and categories of users. The mobile industry has also evolved rapidly in the last 5 years from single-core mobile platforms to multiple-core mobile application platforms, able to compete in terms of user services with notebooks. New types of devices, like tablets, or shifts in human-computer interface paradigms from button click to screen touch, have opened new perspectives both for users and software developers. This requires an adaptable approach for performance analysis in terms of total quality management for software projects. …


A Performance Comparison Of Conventional And Transverse Flux Linear Switched Reluctance Motors, Nuretti̇n Üstkoyuncu, Krishnan Ramu Jan 2015

A Performance Comparison Of Conventional And Transverse Flux Linear Switched Reluctance Motors, Nuretti̇n Üstkoyuncu, Krishnan Ramu

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a comprehensive comparison between conventional (longitudinal flux) linear switched reluctance machines (CLSRMs) and transverse flux linear switched reluctance machines (TLSRMs) so as to enable engineers to choose a structure suitable for their applications. A commonly-used single-sided CLSRM and 4 different TLSRM structures are considered for the comparison. For a fair comparison of the 2 types of LSRMs, equal dimensions, including equal length and magnetomotive force, are applied as much as possible. The analytical approach and 3-dimensional finite element analysis (FEA) are employed to obtain the performance of these machines. It is proven analytically that the CLSRM has …