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Articles 3601 - 3630 of 7216

Full-Text Articles in Computer Engineering

Intelligent Reorganized Discrete Cosine Transform For Reduced Reference Image Quality Assessment, Tariq Bashir, Imran Usman, Shahnawaz Khan, Junaid Ur Rehman Jan 2017

Intelligent Reorganized Discrete Cosine Transform For Reduced Reference Image Quality Assessment, Tariq Bashir, Imran Usman, Shahnawaz Khan, Junaid Ur Rehman

Turkish Journal of Electrical Engineering and Computer Sciences

Reduced reference image quality assessment does not require the presence of the original image for assessing the quality of a degraded image. This work proposes an intelligent method for reduced reference image quality assessment based on a reorganized discrete cosine transform (RDCT). A genetic algorithm (GA) is used to compute optimized estimation of the generalized Gaussian distribution (GGD), which then approximates the coefficient distribution in the RDCT domain. Experimental results validate that such an intelligent estimation produces far superior results compared to conventional empirical estimation methods as presented in the literature. We compare the proposed technique with a number of …

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Compact Electronically Tunable Quadrature Oscillator Using Single Voltage Differencing Gain Amplifier (Vdga) And All Grounded Passive Elements, Orapin Channumsin, Worapong Tangsrirat Jan 2017

Compact Electronically Tunable Quadrature Oscillator Using Single Voltage Differencing Gain Amplifier (Vdga) And All Grounded Passive Elements, Orapin Channumsin, Worapong Tangsrirat

Turkish Journal of Electrical Engineering and Computer Sciences

This work deals with the design of a compact electronically tunable sinusoidal quadrature oscillator. The proposed quadrature oscillator is designed with a single voltage differencing gain amplifier (VDGA) and all the three grounded passive elements. Its oscillation condition and oscillation frequency can be tuned independently by means of the VDGA transconductance gains. The proposed oscillator also provides the explicit quadrature voltage outputs of almost equal magnitude and low active and passive sensitivity figures. The performance of the oscillator has been demonstrated by PSPICE simulations based on TSMC 0.35-$\mu $m CMOS technology.

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Modeling Of Time Delay-Induced Multiple Synchronization Behavior Of Interneuronal Networks With The Izhikevich Neuron Model, Yüksel Çakir Jan 2017

Modeling Of Time Delay-Induced Multiple Synchronization Behavior Of Interneuronal Networks With The Izhikevich Neuron Model, Yüksel Çakir

Turkish Journal of Electrical Engineering and Computer Sciences

The synchronization behavior of the networks of fast-spiking interneurons is investigated by using one of the phenomenological neural network models, the Izhikevich model. Since electrical and chemical synapses exist within the same networks of inhibitory cells, delayed inhibitory and fast electrical synapses are coupled in the simulations. The effects of hybrid synapses in promoting synchronous activity in neural networks are investigated with short and long time delays. The distinct frequency bands observed in electroencephalography and magnetoencephalography signals are determined using the raster plots of neural networks. For quantitative comparison of activities in networks, the degree of synchrony in the network …

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Late Fusion Of Facial Dynamics For Automatic Expression Recognition, Alessandra Bandrabur, Laura Florea, Cornel Florea, Matei Mancas Jan 2017

Late Fusion Of Facial Dynamics For Automatic Expression Recognition, Alessandra Bandrabur, Laura Florea, Cornel Florea, Matei Mancas

Turkish Journal of Electrical Engineering and Computer Sciences

Installment of a facial expression is associated with contractions and extensions of specific facial muscles. Noting that expression is about changes, we present a model for expression classification based on facial landmarks dynamics. Our model isolates the trajectory of facial fiducial points by wrapping them up in relevant features and discriminating among various alternatives with a machine learning classification system. The used features are geometric and temporal-based and the classification system is represented by a late fusion framework that combines several neural networks with binary responses. The proposed method is robust, being able to handle complex expression classes.

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Impact Of Distributed Generator Controllers On The Coordination Of Overcurrent Relays In Microgrid, Niraj Kumar Choudhary, Soumya Ranjan Mohanty, Ravindra Kumar Singh Jan 2017

Impact Of Distributed Generator Controllers On The Coordination Of Overcurrent Relays In Microgrid, Niraj Kumar Choudhary, Soumya Ranjan Mohanty, Ravindra Kumar Singh

Turkish Journal of Electrical Engineering and Computer Sciences

In the presence of distributed generators (DGs) the fault current sensed by relay in the forward direction is larger than that in the reverse direction. Thus, it is required to have different relay settings for both forward and reverse directions. This paper investigates the impact of DG controller operating modes on the coordination of conventional and dual setting overcurrent relays (OCRs). The different DG control modes are voltage control mode (VCM) and current control mode (CCM). A comparative study of protection coordination is presented in both the operating modes of the DG. This scheme is tested on a 3-bus meshed …

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Time-Time Matrix Z-Score Vector-Based Fault Analysis Method For Series-Compensated Transmission Lines, Oveis Asgari Gashteroodkhani, Behrooz Vahidi, Aydin Zaboli Jan 2017

Time-Time Matrix Z-Score Vector-Based Fault Analysis Method For Series-Compensated Transmission Lines, Oveis Asgari Gashteroodkhani, Behrooz Vahidi, Aydin Zaboli

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel protection method based on time-time (TT) transform for thyristor-controlled series-compensated lines is presented. First, current signals at both sides of the sending and receiving ends are retrieved and processed through time-time domain transform (TT-transform), and a TT-matrix is produced. A proposed index is then compared with a defined threshold (THD) in order to determine fault occurrence and faulted phases. Within less than three cycles of the fault inception, a tripping signal can be sent that is acceptable for the speed of digital relays. After faulted phase selection, considering the TT-matrix of the faulted phases of …

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Trnsys Simulation Of Solar Chimney Power Plants With A Heat Storage Layer, Fei̇ Cao, Yufei Mao, Tianyu Zhu, Liang Zhao Jan 2017

Trnsys Simulation Of Solar Chimney Power Plants With A Heat Storage Layer, Fei̇ Cao, Yufei Mao, Tianyu Zhu, Liang Zhao

Turkish Journal of Electrical Engineering and Computer Sciences

The transient performance of a solar chimney power plant (SCPP) with a heat storage layer is evaluated in the present study. A modified TRNSYS type is built. The ground temperature, wind velocity at the chimney inlet, and the power capacity over two typical days are simulated and compared with and without considering the heat storage layer. SCPP performances with six ground materials (granite, limestone, sandstone, sand, wet soil, and water) are compared. The parameters are postponed for 2-3 h when the heat storage layer is considered. This is the multieffect of solar irradiation, air characteristics, and ambient temperature. The SCPP …

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A Secure Cross-Layer Aodv Routing Method To Detect And Isolate (Sclardi) Black Hole Attacks For Manet, Usha Gopal, Kannimuthu Subramanian Jan 2017

A Secure Cross-Layer Aodv Routing Method To Detect And Isolate (Sclardi) Black Hole Attacks For Manet, Usha Gopal, Kannimuthu Subramanian

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a secure cross-layer--based routing technique (SCLARDI) for a mobile ad hoc network (MANET) is proposed. This technique makes use of ad hoc on-demand routing protocol (AODV) algorithms and honeypot technology to detect and isolate black hole attacks from MANETs. This novel system is compared with the single-layer design techniques and existing cross-layer detection techniques. Out of the tested models, the proposed cross-layer design is the most suitable for MANET security. First, the vulnerabilities of the AODV routing protocol against black hole attacks are analyzed. Second, a secure cross-layer--based AODV routing technique is proposed. The proposed SCLARDI technique …

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Study On The Recognition Method Of Airport Perimeter Intrusion Incidents Based On Laser Detection Technology, Huazhu Wu, Zengcai Wang, Changyou Wang Jan 2017

Study On The Recognition Method Of Airport Perimeter Intrusion Incidents Based On Laser Detection Technology, Huazhu Wu, Zengcai Wang, Changyou Wang

Turkish Journal of Electrical Engineering and Computer Sciences

Currently, detection technology is very important for airport perimeter security. When the perimeter is invaded or destroyed, the perimeter security alarm system can promptly alert personnel. In this paper, based on analysis and comparison of several detection technologies commonly used in airport perimeter security and according to the characteristics of airport perimeters and laser detection, an airport perimeter security alarm system based on laser detection is proposed. It analyzes factors that affect the performance of a laser alarm system, divides intrusions into six categories, estimates the different alarm thresholds by testing, and judges the intrusion category according to the number …

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Case Study On Wavelet Choice Based On Statistical Image Quality Measures, Igor Vujovic, Ivica Kuzmanic Jan 2017

Case Study On Wavelet Choice Based On Statistical Image Quality Measures, Igor Vujovic, Ivica Kuzmanic

Turkish Journal of Electrical Engineering and Computer Sciences

Surveillance applications are under many negative influences, which should be suppressed, because these negative influences result in incorrectness of the motion mask. Suppression of several conflicting requirements can be optimized by a multiobjective approach. This paper proposes a multiobjective approach to selection of wavelets based on two main objectives: statistical image quality measures and execution time. Execution time is a measure of wavelets complexity. Segmentation is the final goal in order to insure precise operation of any surveillance algorithm. This paper presents a case study considering one, two, three, and four goals for wavelet selection comparison. Different wavelets are found …

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Development Of Pmu-Based Backup Wide Area Protection For Power Systems Considering Hif Detection, Saeed Asgharigoavr, Heresh Seyedi Jan 2017

Development Of Pmu-Based Backup Wide Area Protection For Power Systems Considering Hif Detection, Saeed Asgharigoavr, Heresh Seyedi

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a wavelet packet transform (WPT)-based algorithm is proposed to develop and improve the backup wide area protection for power systems equipped with phasor measurement units (PMUs). Faults on power systems such as high impedance faults (HIFs) have specific characteristics that include high frequency components that can be extracted using the WPT, which is one of the important methods in signal processing. The proposed idea uses power system voltage and current, measured by voltage and current transformers, respectively, and calculates high frequency information of voltage and current waveforms. Afterwards, the differences of voltage coefficients of each phase at …

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Matching Points Of Interest With User Context: An Ann Approach, Özgün Yilmaz Jan 2017

Matching Points Of Interest With User Context: An Ann Approach, Özgün Yilmaz

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the design and development of an artificial neural network (ANN) for similarity value calculation in a context-aware system is proposed. This neural network is used by the neural agent of the iConAwa system. Since iConAwa is an intelligent, context-aware, multiagent system, it provides mobile users with context-aware information and services, and also provides communication with each other. Context and points of interest are modeled in a flexible and extensible way by using ontologies. iConAwa derives high-level implicit context from low-level explicit context by inference performed over the context ontology. This approach decouples context reasoning from the source …

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Dynamic Slot-Based Carrier Scheduling Scheme For Downlink Multimedia Traffic Over Lte Advanced Networks With Carrier Aggregation, Ramachandran Vijayarani, Lakshmanan Nithyanandan Jan 2017

Dynamic Slot-Based Carrier Scheduling Scheme For Downlink Multimedia Traffic Over Lte Advanced Networks With Carrier Aggregation, Ramachandran Vijayarani, Lakshmanan Nithyanandan

Turkish Journal of Electrical Engineering and Computer Sciences

Carrier aggregation (CA) in long-term evolution advanced (LTE-A) networks is a promising tool for providing bandwidth extension for high data rate communication. In CA, the efficient scheduling of carriers has imposed a new challenge in the design of delay-sensitive carrier scheduling for mobile multimedia applications. In this paper, a new dynamic slot-based carrier scheduling scheme has been proposed for efficient resource allocation to support the quality of service (QoS) of mobile traffic over CA transmission. The key idea of this scheduling is the allocation of slots for each component carrier based on the queue state information, taking into consideration the …

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Evaluation Of Distance Education Websites: A Hybrid Multicriteria Approach, Mehmet Kabak, Eren Özceylan, Meti̇n Dağdevi̇ren, Tolga Genç Jan 2017

Evaluation Of Distance Education Websites: A Hybrid Multicriteria Approach, Mehmet Kabak, Eren Özceylan, Meti̇n Dağdevi̇ren, Tolga Genç

Turkish Journal of Electrical Engineering and Computer Sciences

This study provides an evaluation model that prioritizes the relative weights of various distance education websites. The proposed approach consists of four sequential steps. In the first step, 25 different subcriteria under 4 major criteria are gathered from the existing literature. Identified criteria are weighted by stakeholders of distance education websites using the analytic network process outlined in the second step. In the third step, the technique for order preference by similarity to ideal solution method is applied in order to rank the 15 different Turkish distance education website alternatives. Finally, in the fourth step, different scenario analyses are applied …

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Adaptive Decision Fusion Based Framework For Short-Term Wind Speed And Turbulence Intensity Forecasting: Case Study For North West Of Turkey, Çi̇ğdem Di̇nçkal, Behçet Uğur Töreyi̇n, Serhat Küçükali̇ Jan 2017

Adaptive Decision Fusion Based Framework For Short-Term Wind Speed And Turbulence Intensity Forecasting: Case Study For North West Of Turkey, Çi̇ğdem Di̇nçkal, Behçet Uğur Töreyi̇n, Serhat Küçükali̇

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an online learning framework called adaptive decision fusion (ADF) is employed for short-term wind speed and turbulence intensity forecasting by use of wind speed data for each season for the city of İzmit, located in the northwest of Turkey. Fixed-weight (FW) linear combination is derived and used for comparison with ADF. Wind speeds and turbulence intensities are predicted from the existing wind speed data and computed turbulence intensities, respectively, using the ADF and FW methods. Simulations are carried out for each season and the results are tested on mean absolute percentage error criterion. It is shown that …

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A New Approach For Minimizing Torque Ripple In A Bldc Motor Drive With A Front End Ido Dc-Dc Converter, Ramya Amirthalingam, Balaji Mahadevan Jan 2017

A New Approach For Minimizing Torque Ripple In A Bldc Motor Drive With A Front End Ido Dc-Dc Converter, Ramya Amirthalingam, Balaji Mahadevan

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a front end integrated dual output (IDO) dc-dc converter for commutation torque ripple reduction in a permanent magnet brushless DC (BLDC) motor drive. The current ripple owed to the inductance and resistance of the motor during commutation instant results in torque ripple. In this work the dc link voltage of the converter is varied at commutation instants to minimize current ripple and hence torque ripple. The wider output range and faster response of the IDO converter make it a suitable choice as a front end converter for minimizing torque ripple. Simulation results validate the proposed converter for …

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Visualization Of Distribution System Planning For Engineers And Decision-Makers, Tomislav Capuder, Hrvoje Pandzic, Igor Kuzle Jan 2017

Visualization Of Distribution System Planning For Engineers And Decision-Makers, Tomislav Capuder, Hrvoje Pandzic, Igor Kuzle

Turkish Journal of Electrical Engineering and Computer Sciences

Planning of an electric distribution network is a complex task, requiring a comprehensive approach that includes collecting and analyzing large amounts of technical and nontechnical data. In addition, the outcome of the planning procedure needs to be supported by economic analysis that provides pathways for future investments. In order to present the planning results to various groups of people, such as technical staff, managers, and politicians, different visualization techniques are used. Data visualization, as a branch of descriptive statistics, is important to understand and present information in an effective manner. The basic idea of visualization is to present data in …

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A Spectral Element Method For The Solution Of Magnetostatic Fields, Ibrahim Mahariq, Atakan Erciyas Jan 2017

A Spectral Element Method For The Solution Of Magnetostatic Fields, Ibrahim Mahariq, Atakan Erciyas

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, we have seen good progress in our capability to simulate complex electromagnetic systems. However, still there exist many challenges that have to be tackled in order to push limits restricting the field of computational electromagnetics upward. One of these challenges is the limitations in the available computational resources. Over several decades, the traditional computational methods, such as finite difference, finite element, and finite volume methods, have been extensively applied in the field of electromagnetics. On the other hand, the spectral element method (SEM) has been recently utilized in some branches of electromagnetics as waveguides and photonic structures for the …

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Hesitant Fuzzy Pairwise Comparison For Software Cost Estimation: A Case Study In Turkey, Ayfer Başar Jan 2017

Hesitant Fuzzy Pairwise Comparison For Software Cost Estimation: A Case Study In Turkey, Ayfer Başar

Turkish Journal of Electrical Engineering and Computer Sciences

Estimating the cost of software is a complex process for almost all engineering companies. Uncertainties about development method, design, estimation process, data, and processing affect the accuracy of estimation. Underestimation results in fewer resources being committed than the project really needs, an unrealistic schedule, and low quality outputs. On the other hand, overestimation wastes resources and causes loss of customer credit. Thus, choosing the appropriate cost estimation method is crucial. Studies in the literature emphasize the importance of empirical, analytical methods and expert judgement. Certain cost estimation techniques have been widely studied in the literature. However, there are limited studies …

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Multiphase Segmentation Based On New Signed Pressure Force Functions And One Level Set Function, Haider Ali, Noor Badshah, Ke Chen, Gulzar Ali Khan, Nosheen Zikria Jan 2017

Multiphase Segmentation Based On New Signed Pressure Force Functions And One Level Set Function, Haider Ali, Noor Badshah, Ke Chen, Gulzar Ali Khan, Nosheen Zikria

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper we propose a new model to detect multiple objects of various intensities in images having maximum, minimum, or middle-intensity background by evolving only one level set function. In this model, a new signed pressure force function based on novel generalized averages is used for segmentation of images with maximum or minimum intensity background. For images with middle-intensity backgrounds, which are indeed challenging for 2-phase models, we propose a new product generalized signed pressure force function. Finally, to give experimental and qualitative evidence, our model is tested on both synthetic and real images with the Jaccard similarity index. …

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Analysis Of A Joined Split-Ring Fss Structure Characterized By Three Resonant Frequencies And A Tuned Enhanced Band Using The Wcip Method, Manel Aouissi, Mohammed Titaouine, Thayuan Rolim De Sousa, Ibtissem Adoui, Alfredo Gomes Neto, Henri Baudrand Jan 2017

Analysis Of A Joined Split-Ring Fss Structure Characterized By Three Resonant Frequencies And A Tuned Enhanced Band Using The Wcip Method, Manel Aouissi, Mohammed Titaouine, Thayuan Rolim De Sousa, Ibtissem Adoui, Alfredo Gomes Neto, Henri Baudrand

Turkish Journal of Electrical Engineering and Computer Sciences

This work presents the analysis of a joined split-ring frequency selective surface (FSS) for X-band applications using the wave concept iterative procedure (WCIP). When the incident normal plane wave is polarized in the $x$ direction, the joined split-ring FSS shows three rejecting bands at 9 GHz, 10.5 GHz, and 11.5 GHz simultaneously with bandwidths of 3.11 GHz, 0.6 GHz, and 1.13 GHz, respectively. Moreover, one rejecting band at 6.5 GHz is present when the FSS is fed with a normal plane excited in the $y$ direction. In addition, the different resonant frequencies can be tuned independently to give rise to …

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K-Nn-Based Classification Of Sleep Apnea Types Using Ecg, Oğuz Han Ti̇muş, Emi̇ne Doğru Bolat Jan 2017

K-Nn-Based Classification Of Sleep Apnea Types Using Ecg, Oğuz Han Ti̇muş, Emi̇ne Doğru Bolat

Turkish Journal of Electrical Engineering and Computer Sciences

Obstructive sleep apnea syndrome (OSAS) is a common sleep disorder that yields cardiovascular diseases, excessive daytime sleepiness, and poor quality of life if not treated. Classification of OSAS from electrocardiograms (ECGs) is a noninvasive method and much more affordable than traditional methods. This study proposes a pattern recognition system for automated apnea diagnosis based on heart rate variability (HRV) and ECG-derived respiratory signals. The k-nearest neighbor (k-NN) classifier has been used to develop the models for classifying the sleep apnea types. For comparison purposes, classification models based on multilayer perceptron, support vector machines, and C4.5 decision tree (C4.5 DT) have …

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Analytical Modeling Of A Coaxial Cylindrical Probe Capacitive Sensor Based On Matlab/Simulink For Conductive Liquids Level Measurements, Majid Toghyani Rizi, Mohammad Hadi Shahrokh Abadi Jan 2017

Analytical Modeling Of A Coaxial Cylindrical Probe Capacitive Sensor Based On Matlab/Simulink For Conductive Liquids Level Measurements, Majid Toghyani Rizi, Mohammad Hadi Shahrokh Abadi

Turkish Journal of Electrical Engineering and Computer Sciences

Measurement of liquid level is an important process variable in the operation of many process industries such as water treatment plants. There are different types of level sensors to measure this parameter, categorized into ultrasonic, capacitive, optical, microwave, magnetostrictive, resistive chain, magnetoresistive, hydrostatic pressure, air bubbler, gamma ray, etc. In this paper, a cylindrical probe capacitive sensor for measuring the level of conductive liquids has been modeled based on a step-by-step mathematical procedure, using MATLAB/Simulink. The steps take the relation between the different capacitances in the model with the height of the conductive liquid into account. The results show a …

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Token-Based Authentication Method For M2m Platforms, Hüseyi̇n Polat, Saadi̇n Oyucu Jan 2017

Token-Based Authentication Method For M2m Platforms, Hüseyi̇n Polat, Saadi̇n Oyucu

Turkish Journal of Electrical Engineering and Computer Sciences

Nowadays the fields in which machine-to-machine (M2M) applications are used and the numbers of M2M devices and users are increasing gradually. In an M2M application, M2M platforms are used in order to follow and analyze the data presented by M2M devices. The communication of multiple users and devices via an M2M platform causes some problems in terms of security. In this study, an M2M platform has been developed by using RestFul web services and NoSQL database. On this platform a token-based authentication method was used for multiple users and devices. In this method, an authorized request approach was adopted for …

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Energy Optimized Scheduling For Non-Preemptive Real-Time Systems, Vasanthamani Kannaian, Visalakshi Palanisamy Jan 2017

Energy Optimized Scheduling For Non-Preemptive Real-Time Systems, Vasanthamani Kannaian, Visalakshi Palanisamy

Turkish Journal of Electrical Engineering and Computer Sciences

Embedded systems have geared up their applications in the field of smart phones, mobile devices, automobiles, and medical instrumentation. Along with the growth of technology, the functional requirements of the systems have also grown multifold. To accommodate these ever increasing functional requirements, the hardware should be designed to include the maximum capability, which in turn increases power consumption. Thus this has to be dynamically managed using software techniques. The dynamic voltage and frequency scaling (DVFS) feature provided in most of the recent processors has enabled power optimization through software. With this feature the processor operating frequency can be reduced on …

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Energy And Area Spectral Efficiency Trade-Off For Mc-Cdma With Carrier Frequency Offset, Junaid Ahmed, Moazzam Islam Tiwana, Omer Ahmed, Sarmad Sohaib Jan 2017

Energy And Area Spectral Efficiency Trade-Off For Mc-Cdma With Carrier Frequency Offset, Junaid Ahmed, Moazzam Islam Tiwana, Omer Ahmed, Sarmad Sohaib

Turkish Journal of Electrical Engineering and Computer Sciences

Intercell interference is a major factor that limits the capacity of cellular wireless communication systems. This paper proposes an accurate statistical model that caters to interference and noise to determine the ergodic capacity. A new expression for ergodic capacity is derived that enables us to calculate area spectral efficiency (ASE) and energy efficiency (EE). This expression has been used to calculate and compare ASE and EE for low and high traffic scenarios with various signal-to-noise ratios and intercell distances.

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A Bidirectional Wireless Power Transfer System For An Electric Vehicle With A Relay Circuit, Chenyang Xia, Wei Wang, Yuling Liu, Kezhang Lin, Yanhe Wang, Xiaojie Wu Jan 2017

A Bidirectional Wireless Power Transfer System For An Electric Vehicle With A Relay Circuit, Chenyang Xia, Wei Wang, Yuling Liu, Kezhang Lin, Yanhe Wang, Xiaojie Wu

Turkish Journal of Electrical Engineering and Computer Sciences

In order to extend the transfer distance, enhance the tolerance for coil misalignment, and improve the capability of energy feedback and power transfer efficiency of conventional wireless power transfer (WPT) systems for electric vehicles, this paper presents a bidirectional WPT topology with a relay circuit. In the proposed topology, the primary and pickup circuits are implemented with virtually identical structures, which can operate in both magnetic field excitation and magnetic field receiving modes to facilitate bidirectional power flow between the primary side and the pickup side. A relay circuit is introduced to achieve high transfer efficiency under special conditions such …

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An Intelligent Pso-Based Energy Efficient Load Balancing Multipath Technique In Wireless Sensor Networks, Sukhchandan Randhawa, Sushma Jain Jan 2017

An Intelligent Pso-Based Energy Efficient Load Balancing Multipath Technique In Wireless Sensor Networks, Sukhchandan Randhawa, Sushma Jain

Turkish Journal of Electrical Engineering and Computer Sciences

To provide a reliable and efficient service, load balancing plays an important role in wireless sensor networks (WSNs). There is a need to maximize the network lifetime for WSNs applications with periodic generation of data. Due to the relationship between energy consumption and network sensor node lifetime, energy consumption in a network should be minimized and balanced in order to increase network lifetime. Energy-efficient load-balancing techniques are needed to solve this problem. In this paper, a particle swarm optimization (PSO)-based energy-efficient load-balancing technique is proposed, in which the required number of routing paths and energy consumption of different nodes and …

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Robust Local Parameter Estimator Based On Least Absolute Value Estimator, Volkan Özdemi̇r, Murat Göl Jan 2017

Robust Local Parameter Estimator Based On Least Absolute Value Estimator, Volkan Özdemi̇r, Murat Göl

Turkish Journal of Electrical Engineering and Computer Sciences

Changes in weather conditions such as temperature and humidity, miscommunication between the control center and circuit breaker transducers and tap changers, and inaccurate manufacturing data may cause parameter errors. Because of incorrect parameters, the state estimator may provide biased state estimates, which may lead to many serious economic and operational results. In order to prevent that, one must identify and correct those parameter errors. This work proposes a local parameter estimator based on the least absolute value (LAV) estimator, which is known to be robust against bad measurements, i.e. measurements with gross error. Considering the increasing number of phasor measurement …

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Constrained Control Allocation For Nonlinear Systems With Actuator Failures Or Faults, Saman Ebrahimi Boukani, Mohammad Javad Khosrowjerdi, Roya Amjadifard Jan 2017

Constrained Control Allocation For Nonlinear Systems With Actuator Failures Or Faults, Saman Ebrahimi Boukani, Mohammad Javad Khosrowjerdi, Roya Amjadifard

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a combination of dynamic constrained control allocation with terminal sliding mode control is proposed for a general class of overactuated nonlinear systems with actuator faults/failures. First, the terminal sliding mode control is designed to converge the system tracking error to zero in a finite-time. Then a control allocation strategy is developed and will be solved by a Lyapunov method, which leads to a dynamic update law with finite-time convergence. This strategy satisfies input limits and when faults/failures occur in some of the actuators, the control signals are automatically redistributed among the healthy actuators. Simulation results on a …

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