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2017

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Articles 991 - 1020 of 1200

Full-Text Articles in Computer Engineering

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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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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Minimizing Reverse Current Flow Due To Distributed Generation Via Optimal Network Reconfiguration, Jasrul Jamani Jamian, Muhammad Mohsin Aman, Muhammad Ariff Baharuddin, Ahmad Safawi Mokhtar, Mohd Noor Abdullah Jan 2017

Minimizing Reverse Current Flow Due To Distributed Generation Via Optimal Network Reconfiguration, Jasrul Jamani Jamian, Muhammad Mohsin Aman, Muhammad Ariff Baharuddin, Ahmad Safawi Mokhtar, Mohd Noor Abdullah

Turkish Journal of Electrical Engineering and Computer Sciences

Distributed generation (DG) is widely used to minimize total power losses in distribution networks. However, one of the problems of DG in a grid system is reverse current flow (RCF), which is when the DG output becomes greater than the connected load. Therefore, this paper proposes a multiobjective artificial bee colony (MOABC) algorithm to determine the optimal network reconfiguration for reducing total RCF in DG. The proposed algorithm is tested on 33-bus radial distribution systems in two different scenarios, i.e. base case and with 50% load. The proposed technique can reduce reverse current by up to 93%; however, the total …

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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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Multiclass Semantic Segmentation Of Faces Using Crfs, Khalil Khan, Nasir Ahmad, Khalil Ullah, Irfanud Din Jan 2017

Multiclass Semantic Segmentation Of Faces Using Crfs, Khalil Khan, Nasir Ahmad, Khalil Ullah, Irfanud Din

Turkish Journal of Electrical Engineering and Computer Sciences

Multiclass semantic image segmentation is widely used in a variety of computer vision tasks, such as object segmentation and complex scene understanding. As it decomposes an image into semantically relevant regions, it can be applied in segmentation of face images. In this paper, an algorithm based on multiclass semantic segmentation of faces is proposed using conditional random fields. In the proposed model, each node corresponds to a superpixel, while the neighboring superpixels are connected to nodes through edges. Unlike previous approaches, which rely on three or four classes, the label set is extended here to six classes, i.e. hair, eyes, …

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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Dynamic Security Enhancement Of Power Systems Using Mean-Variance Mapping Optimization, Cavi̇t Fati̇h Küçüktezcan, Veysel Murat İstemi̇han Genç Jan 2017

Dynamic Security Enhancement Of Power Systems Using Mean-Variance Mapping Optimization, Cavi̇t Fati̇h Küçüktezcan, Veysel Murat İstemi̇han Genç

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a preventive control action that involves both generation rescheduling and load curtailment is proposed for enhancing the dynamic security of large interconnected power systems. The control action is formulated as a security-constrained optimization problem that is solved by mean-variance mapping optimization (MVMO) integrated with a self-adaptive penalization technique and artificial neural networks to develop a fast and effective methodology. The proposed methodology is applied to a 16-generator 68-bus test system to solve the security-constrained optimization problem with both continuous and discrete decision variables. To find a proper and cost-effective solution for the control actions within an acceptable …

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Assessment Of Disordered Voices Based On An Optimized Glottal Source Model, Mounir Boudjerda, Abdellah Kacha Jan 2017

Assessment Of Disordered Voices Based On An Optimized Glottal Source Model, Mounir Boudjerda, Abdellah Kacha

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a method for the assessment of disordered voices is proposed. A feature named mean opening quotient (MOQ) obtained from the glottal source estimation is used as an acoustic cue to summarize the degree of severity of the voice disorder. The analysis method uses the empirical mode decomposition algorithm to estimate the glottal source excitation signal from the speech signal. The logarithm of the magnitude spectrum of the speech signal is decomposed into oscillatory modes, called intrinsic mode functions, that are clustered into two classes, the spectral envelope and the harmonic component. The exploitation of the phase information …

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Unsupervised Learning Of Allomorphs In Turkish, Burcu Can Jan 2017

Unsupervised Learning Of Allomorphs In Turkish, Burcu Can

Turkish Journal of Electrical Engineering and Computer Sciences

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

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

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

Turkish Journal of Electrical Engineering and Computer Sciences

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

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