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Full-Text Articles in Physical Sciences and Mathematics

A Comparative Review Of Regression Ensembles On Drug Design Datasets, Mehmet Fati̇h Amasyali, Kadri̇ Okan Ersoy Jan 2013

A Comparative Review Of Regression Ensembles On Drug Design Datasets, Mehmet Fati̇h Amasyali, Kadri̇ Okan Ersoy

Turkish Journal of Electrical Engineering and Computer Sciences

Drug design datasets are usually known as hard-modeled, having a large number of features and a small number of samples. Regression types of problems are common in the drug design area. Committee machines (ensembles) have become popular in machine learning because of their good performance. In this study, the dynamics of ensembles used in regression-related drug design problems are investigated with a drug design dataset collection. The study tries to determine the most successful ensemble algorithm, the base algorithm--ensemble pair having the best/worst results, the best successful single algorithm, and the similarities of algorithms according to their performances. We also …


Multiobjective Daily Volt/Var Control In Distribution Systems With Distributed Generation Using Binary Ant Colony Optimization, Reza Azimi, Saeid Esmaeili Jan 2013

Multiobjective Daily Volt/Var Control In Distribution Systems With Distributed Generation Using Binary Ant Colony Optimization, Reza Azimi, Saeid Esmaeili

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a multiobjective daily voltage and reactive power control (Volt/VAr) in radial distribution systems, including distributed generation units. The main purpose is to determine optimum dispatch schedules for on-load tap changer (OLTC) settings at substations, substation-switched capacitors, and feeder-switched capacitors based on the day-ahead load forecast. The objectives are selected to minimize the voltage deviation on the secondary bus of the main transformer, total electrical energy losses, the number of OLTCs, and capacitor operation and voltage fluctuations in distribution systems for the next day. Since this model is the weighted sum of individual objective functions, an analytic hierarchy …


Control, Design, And Implementation Of A Low-Cost Ultracapacitor Test System, Hasan Hüseyi̇n Eroğlu, Ahmet Masum Hava Jan 2013

Control, Design, And Implementation Of A Low-Cost Ultracapacitor Test System, Hasan Hüseyi̇n Eroğlu, Ahmet Masum Hava

Turkish Journal of Electrical Engineering and Computer Sciences

This paper reviews the ultracapacitor (UC) test procedures, establishes simple and economical power electronic conversion system-based UC test equipment, and experimentally evaluates the performance of a UC module. The power converter hardware structure and control algorithms of the designed system are discussed in detail. The high bandwidth and high accuracy current programming capability of the converter for the purpose of charging and discharging the UC, as required during testing, is illustrated via the experimental results. The UC equivalent circuit parameters are extracted. Successful constant current and constant power charging/discharging operating performances are demonstrated. The results of this study help with …


Image Pattern Recognition Technique For The Classification Of Multiple Power Quality Disturbances, Brahmadesam Viswanathan Krishna, Baskaran Kalaiperumal Jan 2013

Image Pattern Recognition Technique For The Classification Of Multiple Power Quality Disturbances, Brahmadesam Viswanathan Krishna, Baskaran Kalaiperumal

Turkish Journal of Electrical Engineering and Computer Sciences

In a practical power system, a power quality (PQ) event often consists of various types of disturbances occurring at the same time. However, most of the existing techniques are trained to classify single disturbances, and hence have very limited usage in classifying real-time data. This work proposes a novel technique to automatically detect and classify multiple disturbances that coexist in PQ monitoring data. The data obtained from PQ monitors are represented in the form of 2-dimensional (2D) images. This 2D data visualization has significant benefits, in that each type of disturbance produces a different type of edge in the image; …


A Novel Approach For The Reconfiguration Of Distribution Systems Considering The Voltage Stability Margin, Mohammad Hasan Hemmatpour, Mohsen Mohammadian, Mohsen Rezaie Estabragh Jan 2013

A Novel Approach For The Reconfiguration Of Distribution Systems Considering The Voltage Stability Margin, Mohammad Hasan Hemmatpour, Mohsen Mohammadian, Mohsen Rezaie Estabragh

Turkish Journal of Electrical Engineering and Computer Sciences

In recent years, the problem of optimum reconfiguration in distribution systems (DSs) has been a task that must be solved in an optimal manner. This paper presents a new approach for the optimal reconfiguration of DSs based on a hierarchical 2-stage optimization problem to improve the power system voltage stability margin and reduce losses incorporating the constraints. The mentioned problem has been modeled as a nonlinear and multiobjective optimization problem. It uses the ability of the developed harmony search algorithm (HSA) as the first stage of the proposed optimization problem to reach the best network configuration. This reconfiguration algorithm starts …


Low-Cost And Power-Efficient Thread Collision Detection Scheme For Shared Caches In A Real-Time Multithreaded Embedded Processor, Emre Özer Jan 2013

Low-Cost And Power-Efficient Thread Collision Detection Scheme For Shared Caches In A Real-Time Multithreaded Embedded Processor, Emre Özer

Turkish Journal of Electrical Engineering and Computer Sciences

This paper addresses an important issue in a real-time multithreaded embedded processor where several active hardware threads share the critical resources such as caches in the processor. Thread interferences or collisions could lead to severe performance degradations on the real-time threads. Although the cache interference issue on real-time multithreaded processors has been studied before, no cost-effective and simpler hardware solutions were proposed to maintain the single thread performance of the real-time thread while still letting the low-priority threads progress. A novel technique called collision tag is proposed to address these issues. Progressively, the collision tag scheme can be reduced into …


Microelectronic Interconnect Modeling With A Periodical Lumped Rlc-Network, Blaise Ravelo Jan 2013

Microelectronic Interconnect Modeling With A Periodical Lumped Rlc-Network, Blaise Ravelo

Turkish Journal of Electrical Engineering and Computer Sciences

A modeling of high-speed microelectronic interconnections based on periodical resistor-inductor-capacitor (RLC) cells is presented in this paper. A theoretical investigation enabling one to determine the interconnect structure transfer function is established. The proposed theory is based on the use of the ABCD matrix product of elementary cells, constituting the whole interconnect structure. After extracting the constituting lumped elements R, L, and C, which model the considered interconnection, examples of the numerical validations were proposed, both in the frequency and time domains. It was demonstrated that by considering a structure comprised of 10 elementary segments in cascade, S-parameters and time-domain results …


A Reputation-Based Privacy Management System For Social Networking Sites, Mehmet Erkan Yüksel, Asim Si̇nan Yüksel, Abdül Hali̇m Zai̇m Jan 2013

A Reputation-Based Privacy Management System For Social Networking Sites, Mehmet Erkan Yüksel, Asim Si̇nan Yüksel, Abdül Hali̇m Zai̇m

Turkish Journal of Electrical Engineering and Computer Sciences

Social networking sites form a special type of virtual community where we share our personal information with people and develop new relationships on the Internet. These sites allow the users to share just about everything, including photos, videos, favorite music, and games, and record all user interactions and retain them for potential use in social data mining. This storing and sharing of large amounts of information causes privacy problems for the users of these websites. In order to prevent these problems, we have to provide strict privacy policies, data protection mechanisms, and trusted and built-in applications that help to protect …


A New Morse Code Scheme Optimized According To The Statistical Properties Of Turkish, Emrah Çi̇çek, Asim Egemen Yilmaz Jan 2013

A New Morse Code Scheme Optimized According To The Statistical Properties Of Turkish, Emrah Çi̇çek, Asim Egemen Yilmaz

Turkish Journal of Electrical Engineering and Computer Sciences

Morse code has been in use for more than 180 years, even though its currently known form is slightly different than the form defined by Morse and Vail. The code book constructed by Vail was optimized according to the statistical properties of English. In this study, we propose a new code book optimized for Turkish and demonstrate that it is information-theoretically possible to achieve about a 10% improvement throughout the coding of Turkish texts by means of our proposal. The outcomes of this might serve as a basis for potential (academic and/or applied) Turkish language-specific lossless data compression studies.


An Event-Driven Wsn Mac Protocol Design Based On Active Node And Dynamic Time Slot Allocation, Nükhet Sazak, İsmai̇l Ertürk, Etem Köklükaya, Murat Çakiroğlu Jan 2013

An Event-Driven Wsn Mac Protocol Design Based On Active Node And Dynamic Time Slot Allocation, Nükhet Sazak, İsmai̇l Ertürk, Etem Köklükaya, Murat Çakiroğlu

Turkish Journal of Electrical Engineering and Computer Sciences

The unique features of wireless sensor networks (WSNs) make them suitable for a wide range of applications in many different areas. However, with many of the protocols and algorithms used in traditional wireless networks, it is usually neither feasible nor possible to apply them directly to WSNs due to the strict resource constraints of tiny sensor nodes. Moreover, application-specific approaches for communication protocols are usually imposed since WSN applications have distinct requirements. In this study, event-driven WSN applications, where a number of sensor nodes are randomly and densely deployed in remote and difficult to reach locations, are targeted. In such …


Optimal Sizing And Siting Distributed Generation Resources Using A Multiobjective Algorithm, Seyed Amir Hosseini, Seyed Siavash Karimi Madahi, Farzad Razavi, Mohsen Karami, Ali Asghar Ghadimi Jan 2013

Optimal Sizing And Siting Distributed Generation Resources Using A Multiobjective Algorithm, Seyed Amir Hosseini, Seyed Siavash Karimi Madahi, Farzad Razavi, Mohsen Karami, Ali Asghar Ghadimi

Turkish Journal of Electrical Engineering and Computer Sciences

The restructuring of the electrical market, improvement in the technologies of energy production, and energy crisis have paved the way for increasing applications of distributed generation (DG) resources in recent years. Installing DG units in a distribution network may result in positive impacts, such as voltage profile improvement and loss reduction, and negative impacts, such as an increase in the short-circuit level. These impacts depend on the type, capacity, and place of these resources. Therefore, finding the optimal place and capacity of DG resources is of crucial importance. Accordingly, this paper is aimed at finding the optimal place and capacity …


An Automated Signal Alignment Algorithm Based On Dynamic Time Warping For Capillary Electrophoresis Data, Fethullah Karabi̇ber Jan 2013

An Automated Signal Alignment Algorithm Based On Dynamic Time Warping For Capillary Electrophoresis Data, Fethullah Karabi̇ber

Turkish Journal of Electrical Engineering and Computer Sciences

Correcting the retention time variation and measuring the similarity of time series is one of the most popular challenges in the area of analyzing capillary electrophoresis (CE) data. In this study, an automated signal alignment method is proposed by modifying the dynamic time warping (DTW) approach to align the time-series data. Preprocessing tools and further optimizations were developed to increase the performance of the algorithm. As a demonstrative case study, the developed algorithm is applied to the analysis of CE data from a selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) evaluation of the RNA secondary structure. The time-shift problem …


Cancer Risk Analysis By Fuzzy Logic Approach And Performance Status Of The Model, Atinç Yilmaz, Kürşat Ayan Jan 2013

Cancer Risk Analysis By Fuzzy Logic Approach And Performance Status Of The Model, Atinç Yilmaz, Kürşat Ayan

Turkish Journal of Electrical Engineering and Computer Sciences

Cancer is the leading life-threatening disease for people in today's world. Although cancer formation is different for each type of cancer, it has been determined by studies and research that stress also triggers cancer types. Early precaution is very important for people who have not fallen ill yet with a disease like cancer that has a high mortality rate and expensive treatment. With this study, we expound that the possibility of developing such disease may be decreased and people could take measures against it. For the 3 cancer types selected as pilot work by introducing a fuzzy logic model, the …


Biogeography-Based Optimization For Voltage Stability Improvement And Reactive Reserve Management, Subramanian Annamalai, Ravi Govinthabamy Jan 2013

Biogeography-Based Optimization For Voltage Stability Improvement And Reactive Reserve Management, Subramanian Annamalai, Ravi Govinthabamy

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a biogeography-based optimization algorithm to enhance the voltage stability of a power system. It computes the optimal quantity of reactive power support with a view to place the static VAR compensator at the most appropriate nodes. The scheme inflicts an effective management of VAR resources in the process of improving the voltage profile and reducing the network losses. It includes the results of IEEE 30-node system to illustrate the feasibility of the approach.


On-Line Self-Learning Pid Controller Design Of Sssc Using Self-Recurrent Wavelet Neural Networks, Soheil Ganjefar, Mojtaba Alizadeh Jan 2013

On-Line Self-Learning Pid Controller Design Of Sssc Using Self-Recurrent Wavelet Neural Networks, Soheil Ganjefar, Mojtaba Alizadeh

Turkish Journal of Electrical Engineering and Computer Sciences

Conventionally, FACTS devices employ a proportional-integral (PI) controller as a supplementary controller. However, the conventional PI controller has many disadvantages. The present paper aims to propose an on-line self-learning PI-derivative (PID) controller design of a static synchronous series compensator for power system stability enhancement and to overcome the PI controller problems. Unlike the PI controllers, the proposed PID controller has a local nature because of its powerful adaption process, which is based on the back-propagation (BP) algorithm that is carried out through an adaptive self-recurrent wavelet neural network identifier (ASRWNNI). In fact, the PID controller parameters are updated in on-line …


Wavelet Multiscale Analysis Of A Power System Load Variance, Samir Avdakovic, Amir Nuhanovic, Mirza Kusljugic, Elvisa Becirovic, Elma Turkovic Jan 2013

Wavelet Multiscale Analysis Of A Power System Load Variance, Samir Avdakovic, Amir Nuhanovic, Mirza Kusljugic, Elvisa Becirovic, Elma Turkovic

Turkish Journal of Electrical Engineering and Computer Sciences

Wavelet transform (WT) represents a very attractive mathematical area for just more than 15 years of its research in applications in electrical engineering. This is mainly due to its advantages over other processing techniques and signal analysis, which is reflected in the time-frequency analysis, and so it has an important application in the processing and analysis of time series. In this paper, for example, the analysis of the hourly load of a real power system over the past few years was performed by applying the continuous WT and using the Morlet wavelet function. The results show that this approach of …


A Real-Time Extraction Of Active And Reactive Current Using Microcontrollers For A Multipulse Statcom, Mehmet Ali̇ Anadol, Musa Aydin, Tankut Yalçinöz Jan 2013

A Real-Time Extraction Of Active And Reactive Current Using Microcontrollers For A Multipulse Statcom, Mehmet Ali̇ Anadol, Musa Aydin, Tankut Yalçinöz

Turkish Journal of Electrical Engineering and Computer Sciences

In power transmission and distribution systems, the design of a compensator that adjusts the power factor without causing additional power losses requires the determination of the reactive current components that are going to be supplied into the system. In this study, the determination of the active and reactive current components is achieved via the use of the nonactive power theory and a microcontroller-based control system. The control system has been implemented with low-cost 16-bit microcontrollers. This system was used to control a 3-phase, 12-pulse laboratory-size prototype of a static synchronous compensator (STATCOM) with the structure of a voltage source converter. …


Role Of Energy Management In Hybrid Renewable Energy Systems: Case Study-Based Analysis Considering Varying Seasonal Conditions, Recep Yumurtaci Jan 2013

Role Of Energy Management In Hybrid Renewable Energy Systems: Case Study-Based Analysis Considering Varying Seasonal Conditions, Recep Yumurtaci

Turkish Journal of Electrical Engineering and Computer Sciences

The recent popularity of alternative energy technologies is mainly promoted by the increasing awareness of environmental concerns as well as the economic impacts of the depleting fossil fuel reserves. Among several alternative technologies, wind- and solar-based energy have been given specific importance with government-based support for providing a cost-effective structure to realize better penetration of such environmentally friendly sources in the energy market. Even these sources are advantageous over the conventional means of energy production from many aspects, a main drawback being the total dependence on the meteorological conditions (wind speed, solar radiation, temperature, etc.) of the wind and solar …


Multiobjective Differential Evolution-Based Performance Optimization For Switched Reluctance Motor Drives, Hedi Yahia, Noureddine Liouane, Rachid Dhifaoui Jan 2013

Multiobjective Differential Evolution-Based Performance Optimization For Switched Reluctance Motor Drives, Hedi Yahia, Noureddine Liouane, Rachid Dhifaoui

Turkish Journal of Electrical Engineering and Computer Sciences

The simple structure, low manufacturing cost, rugged behavior, high torque per unit volume, and wide torque-speed range make a switched reluctance motor (SRM) very attractive for industrial applications. However, these advantages are overshadowed by its inherent high torque ripple, acoustic noise, and difficulty to control. The controlled parameters in SRM drives can be selected as the turn-on angle, the turn-off angle, and the current reference. This paper investigates the problem of optimal control parameters considering the maximum average torque, minimum copper losses, and minimum torque ripple as the main objectives in SRM drives. The use of evolutionary algorithms (EAs) to …


Complexity Reduction Of Rbf Multiuser Detector For Ds-Cdma Using A Genetic Algorithm, Mustafa Uğur Torun, Damla Gürkan Kuntalp Jan 2013

Complexity Reduction Of Rbf Multiuser Detector For Ds-Cdma Using A Genetic Algorithm, Mustafa Uğur Torun, Damla Gürkan Kuntalp

Turkish Journal of Electrical Engineering and Computer Sciences

The optimal receiver for detecting direct sequence code division multiple access (DS-CDMA) signals suffers from computational complexity that increases exponentially with the number of users. Several suboptimal multiuser detectors (MUDs) have been proposed to overcome this problem. Due to the nonlinear nature of the decision boundary of the optimal receiver, it is known that nonlinear receivers outperform linear receivers. Radial basis function (RBF) MUD is a nonlinear suboptimal receiver that can perfectly approximate this decision boundary and it needs no training since it is fully determined when the spreading codes of all users and the channel impulse response (CIR) are …


Comparison Study Of Computational Parameter Values Between Lrn And Narx In Identifying Nonlinear Systems, Farah Hani Nordin, Farrukh Hafiz Nagi, Aidil Azwin Zainul Abidin Jan 2013

Comparison Study Of Computational Parameter Values Between Lrn And Narx In Identifying Nonlinear Systems, Farah Hani Nordin, Farrukh Hafiz Nagi, Aidil Azwin Zainul Abidin

Turkish Journal of Electrical Engineering and Computer Sciences

To determine the nonlinear autoregressive model with exogenous inputs (NARX) parameter values is not an easy task, even though NARX is reported to successfully identify nonlinear systems. Apart from the activation functions, number of layers, layer size, learning rate, and number of epochs, the number of delays at the input and at the feedback loop need to also be determined. The layer recurrent network (LRN) is seen to have the potential to outperform NARX. However, not many papers have reported on using the LRN to identify nonlinear systems. Therefore, it is the aim of this paper to investigate and analyze …


Capability-Based Task Allocation In Emergency-Response Environments: A Coalition-Formation Approach, Afsaneh Fatemi, Kamran Zamanifar, Naser Nematbakhsh Jan 2013

Capability-Based Task Allocation In Emergency-Response Environments: A Coalition-Formation Approach, Afsaneh Fatemi, Kamran Zamanifar, Naser Nematbakhsh

Turkish Journal of Electrical Engineering and Computer Sciences

This paper addresses coalition formation, based on agent capabilities, centered on task allocation in emergency-response environments (EREs). EREs are environments that need fast task completion as their main requirement. We propose a team-based organization model, based on an existing organization model for adaptive complex systems. The model has some key characteristics that are beneficial for EREs: agents act in dynamic, open domains; agents collaborate in completing group tasks; agents may have similar types of capabilities, but at different levels; tasks need different agent capabilities, at collective different levels; and agents are supervised in a partially decentralized manner. We formulate task …


Shape Control Of Cyclic Networks In Multirobot Formations, Tolga Eren Jan 2013

Shape Control Of Cyclic Networks In Multirobot Formations, Tolga Eren

Turkish Journal of Electrical Engineering and Computer Sciences

The first part of this paper examines cycles at the network level of sensing and control architectures that are needed to maintain the shape of a multiagent formation in 2-dimensional space, while the formation moves as a cohesive whole. The key tools used in the paper are rigidity theory and graph theory. The second part of the paper focuses on the planner level and controller level of the architecture by designing the fuzzy planner and fuzzy controller of individual agents. This permits the decomposition of the complex coordination problem into a series of smaller ones. The fuzzy planner and the …


A Rule Induction Algorithm For Knowledge Discovery And Classification, Ömer Akgöbek Jan 2013

A Rule Induction Algorithm For Knowledge Discovery And Classification, Ömer Akgöbek

Turkish Journal of Electrical Engineering and Computer Sciences

Classification and rule induction are key topics in the fields of decision making and knowledge discovery. The objective of this study is to present a new algorithm developed for automatic knowledge acquisition in data mining. The proposed algorithm has been named RES-2 (Rule Extraction System). It aims at eliminating the pitfalls and disadvantages of the techniques and algorithms currently in use. The proposed algorithm makes use of the direct rule extraction approach, rather than the decision tree. For this purpose, it uses a set of examples to induce general rules. In this study, 15 datasets consisting of multiclass values with …


Topology And Control Design Of A Sinusoidal Very Low Frequency High Voltage Generator, Zhigang Liu, Guofeng Li, Ninghui Wang Jan 2013

Topology And Control Design Of A Sinusoidal Very Low Frequency High Voltage Generator, Zhigang Liu, Guofeng Li, Ninghui Wang

Turkish Journal of Electrical Engineering and Computer Sciences

To reduce the volume and the structural complexity of a very low frequency (VLF) high voltage (HV) generator, this paper introduces a novel sinusoidal VLF HV generator with 2 high frequency HV (HFHV) transformers and 2 metal-oxide semiconductor field-effect transistor cascaded HV bridge arms. Series-parallel resonant converter technology is applied to reduce the impact of the distributed parameters, decreasing the power loss and the volume of the transformer. Both the switching frequency and the duty cycle are utilized as actuating variables to cope with the large ranges of output. Simultaneously, the principle of segmental data processing is proposed to obtain …


Unscented Transformation-Based Probabilistic Optimal Power Flow For Modeling The Effect Of Wind Power Generation, Morteza Aien, Mahmood Fotuhi-Firuzabad, Farrokh Aminifar Jan 2013

Unscented Transformation-Based Probabilistic Optimal Power Flow For Modeling The Effect Of Wind Power Generation, Morteza Aien, Mahmood Fotuhi-Firuzabad, Farrokh Aminifar

Turkish Journal of Electrical Engineering and Computer Sciences

The unprecedented increasing penetration of distributed energy resources, mainly harvesting renewable energies, is a direct result of environmental concerns. These types of energy resources bring about more uncertainties in the power system and, consequently, necessitate probabilistic analyses of the system performance. This paper develops a new approach for probabilistic optimal power flow (P-OPF) by adapting the unscented transformation (UT) method. The heart of the proposed method lies in how to produce the sampling points. Appropriate sample points are chosen to perform the P-OPF with a high degree of accuracy and less computational burden in comparison with the features of other …


Mitigation Of Ssr And Lfo With A Tcsc Based-Conventional Damping Controller Optimized By The Pso Algorithm And A Fuzzy Logic Controller, Hasan Gahramani, Akbar Lak, Murtaza Farsadi, Hossein Hosseini Jan 2013

Mitigation Of Ssr And Lfo With A Tcsc Based-Conventional Damping Controller Optimized By The Pso Algorithm And A Fuzzy Logic Controller, Hasan Gahramani, Akbar Lak, Murtaza Farsadi, Hossein Hosseini

Turkish Journal of Electrical Engineering and Computer Sciences

The subsynchronous resonance (SSR) phenomenon may occur when a steam turbine-generator is connected to a long transmission line with series compensation. Flexible AC transmission systems (FACTS) devices are widely applied to damp the SSR and low-frequency oscillation (LFO). A thyristor-controlled series capacitor (TCSC) is a commercially available FACTS device that was developed for damping the SSR and LFO. In this paper, 2 control methods for damping the SSR and LFO are added to the TCSC main controller in order to demonstrate that the SSR damping capability of the TCSC can be enhanced by proper modulation of the firing angle. The …


Antiwindup Design For The Speed Loop Pi Controller Of A Pmsm Servo System, Ming Yang, Li Niu, Dian-Guo Xu Jan 2013

Antiwindup Design For The Speed Loop Pi Controller Of A Pmsm Servo System, Ming Yang, Li Niu, Dian-Guo Xu

Turkish Journal of Electrical Engineering and Computer Sciences

A novel antiwindup (AW) strategy for a proportional-integral (PI) regulator based on the back-calculation method is presented. The proposed method will calculate the gain of the back-calculation based on the input and output status of the PI regulator without the requirement of motor parameters, such as the inertial and torque-current coefficient, and the back-calculation gain will vary with the speed command in order to obtain the optimal dynamic performance. The proposed method avoids the problem caused by the fixed back-calculation gain in the classical AW strategy, and prevents the system from untimely saturation withdrawing or an unexpected overshoot due to …


Feature-Based Fault Detection Of Industrial Gas Turbines Using Neural Networks, Abbas Rasaienia, Behzad Moshiri, Mohammadamin Moezzi Jan 2013

Feature-Based Fault Detection Of Industrial Gas Turbines Using Neural Networks, Abbas Rasaienia, Behzad Moshiri, Mohammadamin Moezzi

Turkish Journal of Electrical Engineering and Computer Sciences

Gas turbine (GT) fault detection plays a vital role in the minimization of power plant operation costs associated with power plant overhaul time intervals. In other words, it is helpful in generating pre-alarms and paves the way for corrective actions in due time before incurring major equipment failures. Hence, finding an efficient fault detection technique that is applicable in the online operation of power plants involved with minor computations is an urgent need in the power generation industry. Such a method is studied in this paper for the V94.2 class of GTs. As the most leading stage for developing a …


Shifted-Modified Chebyshev Filters, Meti̇n Şengül Jan 2013

Shifted-Modified Chebyshev Filters, Meti̇n Şengül

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces a new type of filter approximation method that utilizes shifted-modified Chebyshev filters. Construction of the new filters involves the use of shifted-modified Chebyshev polynomials that are formed using the roots of conventional Chebyshev polynomials. The study also includes 2 tables containing the shifted-modified Chebyshev polynomials and the normalized element values for the low-pass prototype filters up to degree 6. The transducer power gain, group delay, and impulse and step responses of the proposed filters are compared with those of the Butterworth and Chebyshev filters, and a sixth-order filter design example is presented to illustrate the implementation of …