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Full-Text Articles in Engineering

Lambda Optimization Of Constraint Violating Units In Short-Term Thermal Unit Commitment Using Modified Dynamic Programming, Logavani Kandasamy, Senthil Kumar Selvaraj Jan 2017

Lambda Optimization Of Constraint Violating Units In Short-Term Thermal Unit Commitment Using Modified Dynamic Programming, Logavani Kandasamy, Senthil Kumar Selvaraj

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new approach with a three-stage optimization algorithm for the least-cost optimal solution of the unit commitment problem. In the proposed work, the optimal schedule is obtained by optimizing the lambda operator for the states that violate the inequality constraints. The objective of the work is to minimize the fuel cost when subjected to various constraints such as load balance, minimum up/down time, ramp limit, and spinning reserve. This method of committing the units yields the least-cost solution when applied to the IEEE 10-unit systems and 7-unit Indian utility practical systems scheduled for 24 h and the …


Dual Broadband Antenna With Compact Double Ring Radiators For Ieee 802.11 Ac/B/G/N Wlan Communication Applications, Meri̇h Palandöken Jan 2017

Dual Broadband Antenna With Compact Double Ring Radiators For Ieee 802.11 Ac/B/G/N Wlan Communication Applications, Meri̇h Palandöken

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a dual broadband antenna is proposed for WLAN communication modules supported by the IEEE 802.11 ac/b/g/n standard. The antenna design is based on two interspaced electrically small split-ring resonators, each of which is directly fed through the stepped impedance microstrip line with an optimized electromagnetic coupling distance in between. The proposed dual band antenna operates in the lower frequency band from 2.3 GHz up to 3 GHz with 2.65 GHz center frequency (26.4 % bandwidth) and in the higher frequency band from 4.7 GHz up to 6 GHz with 5.35 GHz center frequency (24.3% bandwidth). The radiating …


Dvcc-Based Floating Capacitance Multiplier Design, Hali̇l Alpaslan Jan 2017

Dvcc-Based Floating Capacitance Multiplier Design, Hali̇l Alpaslan

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a floating capacitance multiplier including two multioutput differential voltage current conveyors, two grounded resistors, and a grounded capacitor is proposed. The proposed floating capacitance multiplier can realize high capacitor values with two small-valued resistors. It is more suitable for integrated circuit technology because it has only grounded passive components without needing any critical passive component matching conditions. Its performances are examined with several simulations using the SPICE program. As an application example, a third-order notch filter using three resistors and three capacitors is given.


Vector Control Of Unbalanced 3-Phase Im Using Forward And Backward Components, Mohammad Jannati, Nik Rumzi Nik Idris Jan 2017

Vector Control Of Unbalanced 3-Phase Im Using Forward And Backward Components, Mohammad Jannati, Nik Rumzi Nik Idris

Turkish Journal of Electrical Engineering and Computer Sciences

In some industries, continuous operation of 3-phase induction motors (IMs) even under faults until the scheduled maintenance time is essential. Conventional control techniques such as field-oriented control (FOC) cannot be used to control faulty IMs since this will result in significant oscillations in the speed and torque. Consequently, a new control approach must be developed for improving IM performance during fault conditions. This paper presents a method for vector control of 3-phase IMs under open-phase faults. The main advantage of this control scheme is its ability to handle not only one phase but also two phases of open-phase fault conditions. …


Energy-Hole Avoidance And Lifetime Enhancement Of A Wsn Through Load Factor, Krishna Pal Sharma, Teek Parval Sharma Jan 2017

Energy-Hole Avoidance And Lifetime Enhancement Of A Wsn Through Load Factor, Krishna Pal Sharma, Teek Parval Sharma

Turkish Journal of Electrical Engineering and Computer Sciences

In wireless sensor networks, nonuniform communication load across a network often leads to the problem of energy holes or hot spots, i.e. nodes nearer high activity regions deplete their energy much faster than nodes elsewhere. This may partition the network into unreachable segments and thus adversely affect network lifetime. The problem is more acute in random and sparsely deployed networks. Therefore, we propose a deployment strategy that, using the least possible nodes, prolongs network lifetime by avoiding energy holes and also ensures full sensing and communication coverage. The scheme handles the energy imbalance by selecting an appropriate set of communication …


Tunable Microstrip Dual-Band Bandpass Filter For Wlan Applications, Abbas Rezaei, Leila Noori Jan 2017

Tunable Microstrip Dual-Band Bandpass Filter For Wlan Applications, Abbas Rezaei, Leila Noori

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, based on a new stub-loaded open loop resonator, a compact microstrip dual-band bandpass filter is presented. The proposed filter is designed using two stub-loaded open loop resonators to create two pass bands at 2.39 GHz and 5.7 GHz for multimode wireless LANs applications. Two high impedance sections are used in the main loops and the internal stubs are two low impedance microstrip cells. A method is presented to control the mode resonance frequencies. By increasing the internal stubs' dimensions, the resonance frequencies are adjusted without size increment. The proposed filter has a good performance. The insertion losses …


An Extremely Wideband Radome-Enclosed Cylindrical Dipole Antenna For Wireless Communication, Tariq Rahim, Jiadong Xu Jan 2017

An Extremely Wideband Radome-Enclosed Cylindrical Dipole Antenna For Wireless Communication, Tariq Rahim, Jiadong Xu

Turkish Journal of Electrical Engineering and Computer Sciences

A radome-enclosed extremely wideband cylindrical dipole antenna for wireless communications applications was proposed with a simple structure. The antenna is fed at the center with the help of a coaxial cable through the lower hollow metallic pole. The feed area is composed of cones at both sides in order to obtain wideband impedance matching. The proposed antenna can cover 1.8 GHz to 28 GHz with S11 of less than -10 dB and excellent stable omnidirectional radiation characteristics. However, at high frequencies, some ripples are introduced in the radiation pattern. The frequency band of the cylindrical dipole antenna can be controllable …


Design And Operation Of A Multifunction Photovoltaic Power System With Shunt Active Filtering Using A Single-Stage Three-Phase Multilevel Inverter, Serkan Sezen, Ahmet Aktaş, Mehmet Uçar, Engi̇n Özdemi̇r Jan 2017

Design And Operation Of A Multifunction Photovoltaic Power System With Shunt Active Filtering Using A Single-Stage Three-Phase Multilevel Inverter, Serkan Sezen, Ahmet Aktaş, Mehmet Uçar, Engi̇n Özdemi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the control of a multifunction grid-connected photovoltaic (PV) system with a three-phase three-level (3L) neutral point clamped (NPC) inverter is proposed, which can perform shunt active filtering. Normally, the shunt active filtering is achieved by detecting the harmonic and reactive currents of the nonlinear load and then injecting the compensating current into the grid. Therefore, the proposed system can inject PV power to a grid with power factor correction and current harmonic filtering features simultaneously. In addition, a single-stage compact and efficient transformerless power conversion topology is used in this paper for the grid-connected solar PV system …


Effect Of Micro/Nano-Sio$_{2}$ On Mechanical, Thermal, And Electrical Properties Of Silicone Rubber, Epoxy, And Epdm Composites For Outdoor Electrical Insulations, Hidayatullah Khan, Muhammad Amin, Muhammad Ali, Muhammad Iqbal, Muhammad Yasin Jan 2017

Effect Of Micro/Nano-Sio$_{2}$ On Mechanical, Thermal, And Electrical Properties Of Silicone Rubber, Epoxy, And Epdm Composites For Outdoor Electrical Insulations, Hidayatullah Khan, Muhammad Amin, Muhammad Ali, Muhammad Iqbal, Muhammad Yasin

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper the influence of micro-sized (3 $\mu $m) and nano-sized (10 nm) silica (SiO$_{2})$ on mechanical, thermal, and electrical properties of silicon rubber (SiR), epoxy, and ethylene propylene diene monomer (EPDM) composites is presented. The micro- and nano-sized SiO$_{2}$ particle-filled SiR, epoxy, and EPDM composites were formulated with 20% microsilica and 5% nanosilica by weight respectively. Among these composites, SiR-SiO$_{2}$ amalgamation was performed by mixing using an ultrasonication procedure. Epoxy-SiO$_{2}$ was compounded in two steps, i.e. dispersion of fillers and mixing, whereas EPDM-SiO$_{2}$ compounding was performed with a two roll mill technique. With the addition of micro/nano-SiO$_{2}$, the …


Truncation Thresholds: A Pair Of Spike Detection Thresholds Computed Using Truncated Probability Distributions, Murat Okatan, Mehmet Kocatürk Jan 2017

Truncation Thresholds: A Pair Of Spike Detection Thresholds Computed Using Truncated Probability Distributions, Murat Okatan, Mehmet Kocatürk

Turkish Journal of Electrical Engineering and Computer Sciences

We describe a method for computing a pair of spike detection thresholds, called `truncation thresholds', using truncated probability distributions, for extracellular recordings. In existing methods the threshold is usually set to a multiple of an estimate of the standard deviation of the noise in the recording, with the multiplication factor being chosen between 3 and 5 according to the researcher's preferences. Our method has the following advantages over these methods. First, because the standard deviation is usually estimated from the entire recording, which includes the spikes, it increases with firing rate. By contrast, truncation thresholds decrease in absolute value with …


A Cell-Based 5-Mhz On-Chip Clock Generator, Ching-Che Chung, Jhih-Wei Li Jan 2017

A Cell-Based 5-Mhz On-Chip Clock Generator, Ching-Che Chung, Jhih-Wei Li

Turkish Journal of Electrical Engineering and Computer Sciences

A cell-based 5-MHz on-chip clock generator for smart sensing applications is presented. By exploiting relative reference modeling, our proposed design can dynamically track both voltage and temperature variations after four-point chip calibrations. The proposed on-chip clock generator is fabricated using a 90-nm CMOS process, the frequency stability is 160 ppm/$^{\circ}$C and 72 ppm/mV over 0 $^{\circ}$C to 75 $^{\circ}$C and 0.9 V to 1.1 V, and the settling time of the proposed on-chip clock generator is 5.12 $\mu$s. The proposed on-chip clock generator was implemented with standard cells that can greatly reduce the design complexity and design time for on-chip …


Design And Test Of A New Development Fpga Board For Mobile Robot Research, Baligh Naji, Chokri Abdelmoula, Karim Abbes, Mohamed Masmoudi Jan 2017

Design And Test Of A New Development Fpga Board For Mobile Robot Research, Baligh Naji, Chokri Abdelmoula, Karim Abbes, Mohamed Masmoudi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the design and testing of a newly developed field programmable gate array (FPGA) board for mobile robot research. The idea consists of interfacing the FPGA to a 16-bit digital signal controller (dsPIC). This idea enables the FPGA designs to communicate with the dsPIC through the integration of per-written driver modules to be used in a wide variety of digital and analog peripheral modules. It also allows the use of a high-performance digital signal processing core in many signal processing-based mobile robot applications. The proposed FPGA board allows users to develop, test, and deploy quick and cost-effective complete …


Early Detection Of Sudden Cardiac Death Using Poincaré Plots And Recurrence Plot-Based Features From Hrv Signals, Vahid Houshyarifar, Mehdi Chehel Amirani Jan 2017

Early Detection Of Sudden Cardiac Death Using Poincaré Plots And Recurrence Plot-Based Features From Hrv Signals, Vahid Houshyarifar, Mehdi Chehel Amirani

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper we present a method to predict sudden cardiac death (SCD) based on the heart rate variability (HRV) signal and recurrence plots and Poincaré plot-extracted features. This work is a challenge since it is aimed to devise a method to predict SCD 5 min before its onset. The method consists of four steps: preprocessing, feature extraction, feature reduction, and classification. In the first step, the QRS complexes are detected from the electrocardiogram signal and then the HRV signal is extracted. In the second step, the recurrence plot of the HRV signal and Poincaré plot-extracted features are obtained. Four …


New Static Output Feedback Stabilization And Multivariable Pid-Controller Design Methods For Unstable Linear Systems Via An Ilmi Optimization Approach, Mehmet Nur Alpaslan Parlakçi, Elbrus Caferov Jan 2017

New Static Output Feedback Stabilization And Multivariable Pid-Controller Design Methods For Unstable Linear Systems Via An Ilmi Optimization Approach, Mehmet Nur Alpaslan Parlakçi, Elbrus Caferov

Turkish Journal of Electrical Engineering and Computer Sciences

The design problem of a static output feedback controller and multivariable proportional-integral-derivative (PID) controller is investigated for linear time-invariant systems (LTI). First, the static output feedback stabilization problem is taken into consideration and then an iterative linear matrix inequality (ILMI) algorithm is developed for the synthesis of the controller. Second, choosing a multivariable PID control law, the whole system is transformed into a new augmented system represented in the form of a static output feedback control system. This method allows us to convert the multivariable PID controller design problem into a static output feedback synthesis problem. Thus, the proposed ILMI …


Comparative Study Of Conventional Modulation Schemes In Terms Of Conducted And Radiated Emi Generated By Three-Phase Inverters, Mohamed Salem, Mahmoud Hamouda, Jaleleddine Ben Hadj Slama Jan 2017

Comparative Study Of Conventional Modulation Schemes In Terms Of Conducted And Radiated Emi Generated By Three-Phase Inverters, Mohamed Salem, Mahmoud Hamouda, Jaleleddine Ben Hadj Slama

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a comparative study is carried out between the carrier (SPWM), third harmonic injection (THIPWM), and space vector (SVPWM) modulation schemes in terms of conducted (common and differential modes) and radiated electromagnetic interference (EMI) generated by three-phase two-level voltage source inverters. For this purpose, an experimental setup of the converter feeding an induction machine is developed with the aim to measure the conducted emission propagated back into the dc source and the radiated field in the vicinity of the power conversion device. Experimental results are given and analyzed in time and frequency domains. The comparative study between the …


Assignment As A Location-Based Service In Outsourced Databases, Ahmet Sali̇h Büyükkayhan, Taflan İmre Gündem Jan 2017

Assignment As A Location-Based Service In Outsourced Databases, Ahmet Sali̇h Büyükkayhan, Taflan İmre Gündem

Turkish Journal of Electrical Engineering and Computer Sciences

Location-based services provide opportunities to organizations for tracking and utilizing their resources. Moreover, some corporations prefer to outsource their database management services. In the literature, privacy preservation techniques in outsourced spatial databases for several query types, such as nearest neighbor, K-nearest neighbor, and proximity search, have been examined. In this paper, we present an efficient application of the capacity and coverage-constrained assignment query on outsourced spatial databases. In the proposed technique, we introduce a novel spatial transformation strategy (square spiral encoding) to achieve privacy efficiently for approximate assignment query results. To process the assignment query, we use the parallel auction …


Neural Network Approach On Loss Minimization Control Of A Pmsm With Core Resistance Estimation, Hüseyi̇n Erdoğan, Mehmet Özdemi̇r Jan 2017

Neural Network Approach On Loss Minimization Control Of A Pmsm With Core Resistance Estimation, Hüseyi̇n Erdoğan, Mehmet Özdemi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

Permanent magnet synchronous motors (PMSMs) are often used in industry for high-performance applications. Their key features are high power density, linear torque control capability, high efficiency, and fast dynamic response. Today, PMSMs are prevalent especially for their use in hybrid electric vehicles. Since operating the motor at high efficiency values is critically important for electric vehicles, as for all other applications, minimum loss control appears to be an inevitable requirement in PMSMs. In this study, a neural network-based intelligent minimum loss control technique is applied to a PMSM. It is shown by means of the results obtained that the total …


Design Of A Self-Starting Hybrid Permanent Magnet Hysteresis Synchronous Motor Connected Directly To The Grid, Mehmet Gedi̇kpinar, Ömür Aydoğmuş Jan 2017

Design Of A Self-Starting Hybrid Permanent Magnet Hysteresis Synchronous Motor Connected Directly To The Grid, Mehmet Gedi̇kpinar, Ömür Aydoğmuş

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, a permanent magnet hysteresis synchronous (PMHS) motor was designed to improve the efficiency of the system. The proposed motor is intended for pumping applications, such as submersible pump motors, fire pumps, oil-well pumps, and circulation pumps requiring high-speed operation. The efficiency of the pump system increases depending on the speed of the pump fans. The total efficiency of the pump system is reduced because the load increases exponentially in these types of application systems. The speed is important for the pumping applications in order to improve the efficiency of the pump system. Nowadays, traditional induction motors are …


Training Anfis By Using The Artificial Bee Colony Algorithm, Dervi̇ş Karaboğa, Ebubeki̇r Kaya Jan 2017

Training Anfis By Using The Artificial Bee Colony Algorithm, Dervi̇ş Karaboğa, Ebubeki̇r Kaya

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a new adaptive network-based fuzzy inference system (ANFIS) training algorithm, the artificial bee colony (ABC) algorithm, is presented. Antecedent and conclusion parameters existing in the structure of ANFIS are optimized with the ABC algorithm and ANFIS training is realized. Identification of a set of nonlinear dynamic systems is performed in order to analyze the suggested training algorithm. The ABC algorithm is operated 30 times for each identification case and the average root mean square error (RMSE) value is obtained. Training RMSE values calculated for the four examples considered are 0.0325, 0.0215, 0.0174, and 0.0294, respectively. In addition, …


Research On Magnetic Field State Analysis Of A Nonsalient Pole Synchronous Generator, Baojun Ge, Pin Lv, Dajun Tao, Fang Xiao, Hongsen Zhao Jan 2017

Research On Magnetic Field State Analysis Of A Nonsalient Pole Synchronous Generator, Baojun Ge, Pin Lv, Dajun Tao, Fang Xiao, Hongsen Zhao

Turkish Journal of Electrical Engineering and Computer Sciences

This paper is based on the definition of minor asymmetric degree and the relative position of the magnetic field. The relative position of the magnetic field is the angle between the positive and negative sequence magnetic fields. The corresponding relationship between the nonsalient pole synchronous generator steady performance and the magnetic field state is discussed when the generator operates at minor asymmetry. To analyze this corresponding relationship, the Taylor expansion formula with Lagrange remainder and symmetrical components is adopted. We study the relationship between the armature current and the relative position of the magnetic field, deducing the armature current expressions …


Loss Minimization In Wind Farm Integrated Ac/Dc System By Optimal Injections And Droop Settings Of Vsc-Mtdc Systems, Anbuselvi Shanmugam Velu, Somasundaram Periyasamy, Kumudini Devi Raguru Pandu Jan 2017

Loss Minimization In Wind Farm Integrated Ac/Dc System By Optimal Injections And Droop Settings Of Vsc-Mtdc Systems, Anbuselvi Shanmugam Velu, Somasundaram Periyasamy, Kumudini Devi Raguru Pandu

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a modified optimal power flow (OPF) model, incorporating a voltage source converter-based multiterminal DC (VSC-MTDC) system, is proposed. The OPF is formulated to minimize the losses, steady state voltage deviations, and overloading of the AC/DC system. The control variables considered in this modified OPF model are power injection into the DC system and droop settings. Optimal injection patterns for different wind power penetrations and optimal droop settings are evaluated for wind farm side converters and grid side converters, respectively. Wind power penetrations are routed into AC and DC lines in different proportions to optimize the flows in …


Effect Of Touch Coordinate Display As A Form Of Augmented, Concurrent Visual Feedback On The Accuracy Of Single-Handed Typing Via Smartphone Virtual Keyboards, Abdullah Ruhi̇ Soylu, Görkem Yavaş, Bora Ergi̇n, Sumru Keçeli̇ Jan 2017

Effect Of Touch Coordinate Display As A Form Of Augmented, Concurrent Visual Feedback On The Accuracy Of Single-Handed Typing Via Smartphone Virtual Keyboards, Abdullah Ruhi̇ Soylu, Görkem Yavaş, Bora Ergi̇n, Sumru Keçeli̇

Turkish Journal of Electrical Engineering and Computer Sciences

This study assessed the effect of an easily perceived real-time visual feedback method on touchscreen typing accuracy. Thirty subjects were asked to hold a smartphone with a capacitive touchscreen in one hand and enter a text using the thumb of the same hand via a custom designed virtual keyboard. There were two types of text entry sessions: with or without visual feedback. The visual feedback consisted of a full-screen crosshair, representing the accurate coordinate of touch in real time. In each session, touch-down time on the virtual keyboard and touch coordinates were recorded for every touch action. Two types of …


An Improved Clonal Selection Algorithm Using A Tournament Selection Operator And Its Application To Microstrip Coupler Design, Ezgi̇ Deni̇z Ülker Jan 2017

An Improved Clonal Selection Algorithm Using A Tournament Selection Operator And Its Application To Microstrip Coupler Design, Ezgi̇ Deni̇z Ülker

Turkish Journal of Electrical Engineering and Computer Sciences

The clonal selection algorithm (CLONALG) is a nature-inspired metaheuristic algorithm that has been applied to various complex optimization problems from different fields of study. Tournament selection (TS) is a selection operator that is mainly used in genetic algorithms. In this paper, a novel improved clonal selection algorithm by using the TS operator (ICSAT) is introduced. To observe the improvement, ICSAT was first tested on selected benchmark functions and then to validate its efficiency ICSAT was applied to a microstrip coupler design problem. Although showing some disadvantages that generally exist in all modified algorithms, it is observed that ICSAT has a …


Regional Ionospheric Trend Statistics: Ionolab-Pdf, Ozan Köroğlu, Feza Arikan Jan 2017

Regional Ionospheric Trend Statistics: Ionolab-Pdf, Ozan Köroğlu, Feza Arikan

Turkish Journal of Electrical Engineering and Computer Sciences

The ionosphere plays an important role for HF bands, space-based positioning systems, satellite communication, and propagation. The variability of the ionosphere has a complex spatiotemporal characteristic, which depends on statistical parameters. Total electron content (TEC) is one of the major observables for investigating and determining this variability. In this study, spatiotemporal within-the-hour statistical characteristics of TEC are determined for Turkey, which is located in midlatitude, using the TEC estimates from the Turkish National Permanent GPS Network-Active between the years 2009 and 2012. The TEC values have strong hourly, seasonal, and positional dependence on east-west direction, and the trend shifts according …


Breast Boundary Segmentation In Thermography Images Based On Random Walkers, Mehrdad Moghbel, Syamsiah Mashohor, Rozi Mahmud, M.Iqbal Bin Saripan, Suzana Abd Hamid, Suraini Mohamad Sani, Saiful Nizam Jan 2017

Breast Boundary Segmentation In Thermography Images Based On Random Walkers, Mehrdad Moghbel, Syamsiah Mashohor, Rozi Mahmud, M.Iqbal Bin Saripan, Suzana Abd Hamid, Suraini Mohamad Sani, Saiful Nizam

Turkish Journal of Electrical Engineering and Computer Sciences

Breast and areola boundary detection and segmentation present the biggest challenge in breast segmentation from thermography images, as breast boundaries, especially in the upper quadrants of the breast, are nonexistent. Many segmentation approaches have been proposed for breast segmentation, such as active contours and snakes, circular Hough transforms, and live wires, but these methods often fail to achieve satisfactory results. With recent advances in image processing techniques, new segmentation concepts are being developed, such as random walkers, which have received high interest from the medical imaging community. In this study, 91 images acquired utilizing a FLIR A320 thermal camera are …


Statistical Features-Based Comparison Of Analysis And Synthesis Of Normal And Epileptic Electroencephalograms For Various Wavelets, Revati Shriram, Mahalingam Sundhararajan, Supriya Shete, Nivedita Daimiwal Jan 2017

Statistical Features-Based Comparison Of Analysis And Synthesis Of Normal And Epileptic Electroencephalograms For Various Wavelets, Revati Shriram, Mahalingam Sundhararajan, Supriya Shete, Nivedita Daimiwal

Turkish Journal of Electrical Engineering and Computer Sciences

An electroencephalogram (EEG) is an electrical signal in microvolts captured noninvasively from the brain, which provides important and unique information about the brain. The frequency of an EEG signal lies between 0 and 100 Hz. Decomposition of an EEG signal into various bands such as alpha, beta, delta, theta, and gamma is essential in seizure-related studies. EEGs play a key role in the diagnosis of epileptic seizures and neurological disorders. In this paper, multiple wavelet families for decomposition and reconstruction are explored and are compared based on risk functions and reconstruction measures. While dealing with the wavelets it is a …


Automobile Engine Condition Monitoring Using Sound Emission, Hamid Ghaderi, Peyman Kabiri Jan 2017

Automobile Engine Condition Monitoring Using Sound Emission, Hamid Ghaderi, Peyman Kabiri

Turkish Journal of Electrical Engineering and Computer Sciences

A wavelet packet transform (WPT) is a well-known technique used for data and signal-processing that has proven to be successful in condition monitoring and fault diagnosis. In this study, using feature extraction based on wavelet transformation, sound signals emitted from automobile engines under both faulty and healthy conditions are analyzed. The intention is to categorize sound signals into both healthy and faulty classes. Sound signals are generated from 4 different automobile engines in both healthy and faulty conditions. The investigated fault is within the ignition system of the engines. In addition, there are other possible problems that may also affect …


Error Sources And Measurement Uncertainties In Outdoor Testing Of Bipv Modules, Kivanç Başaran Jan 2017

Error Sources And Measurement Uncertainties In Outdoor Testing Of Bipv Modules, Kivanç Başaran

Turkish Journal of Electrical Engineering and Computer Sciences

Although building-integrated photovoltaic (BIPV) systems have great potential, investment in this field is not at the desired level. There are two main reasons for this: the lack of technical analysis and economic reasons. Manufacturers and investors utilize datasheets of modules to determine the systems performance, which is determined at standard test conditions (STCs). However, there are apparent differences between STCs and outdoor measurements. Most studies in the field of BIPV system analysis have only focused on long-term outdoor measurements. Besides that, uncertainty of measurements is necessary to achieve scientific results. The aim of this study is to emphasize the importance …


Load Shedding Scheme Based On Frequency And Voltage Stability For An Islanding Operation Of A Distribution Network Connected To Mini-Hydro Generation, Norazliani Md Sapari, Hazlie Bin Mokhlis, Javed Ahmed Laghari, Ab Halim Abu Bakar, Hasmaini Mohamad, Mohd Rohaimi Mohd Dahalan Jan 2017

Load Shedding Scheme Based On Frequency And Voltage Stability For An Islanding Operation Of A Distribution Network Connected To Mini-Hydro Generation, Norazliani Md Sapari, Hazlie Bin Mokhlis, Javed Ahmed Laghari, Ab Halim Abu Bakar, Hasmaini Mohamad, Mohd Rohaimi Mohd Dahalan

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a load shedding scheme (LSS) based on system frequency and voltage stability (VS). In the proposed scheme, the amount of power imbalance is determined using a rate of change of frequency, and the load shedding priority is carried out based on a VS index. The load with the highest tendency for voltage collapse (based on the index value) is given first priority to be shed. Thus, by shedding the most sensitive load, the distribution system can be saved from power collapse and then the system can return to its nominal state after load shedding. The proposed LSS …


Accelerating The Solving Of Nonlinear Equations Using The Homotopy Method: Application On Finding The Operating Point Of Complex Circuits, Fathi Dhiabi, Mohamed Boumehraz Jan 2017

Accelerating The Solving Of Nonlinear Equations Using The Homotopy Method: Application On Finding The Operating Point Of Complex Circuits, Fathi Dhiabi, Mohamed Boumehraz

Turkish Journal of Electrical Engineering and Computer Sciences

Analog circuits with nonlinear elements (e.g., diode, BJT, and CMOS) and integrated circuits are very complex systems. As a result, they are very difficult to analyze because of the need to generate a nonlinear equation system solution in order to do so. Solving nonlinear equations is still a challenging problem. Iterative methods, however, are frequently used to solve them. This paper describes a method that can be used to both accelerate the solving of nonlinear equations and find the operating point in various integrated circuits by construction of the global homotopy equation of the analog circuit. This is done by …