Computer Engineering Commons^™

Achieving High Reliability And Efficiency In Maintaining Large-Scale Storage Systems Through Optimal Resource Provisioning And Data Placement, Lipeng Wan

Doctoral Dissertations

With the explosive increase in the amount of data being generated by various applications, large-scale distributed and parallel storage systems have become common data storage solutions and been widely deployed and utilized in both industry and academia. While these high performance storage systems significantly accelerate the data storage and retrieval, they also bring some critical issues in system maintenance and management. In this dissertation, I propose three methodologies to address three of these critical issues.

First, I develop an optimal resource management and spare provisioning model to minimize the impact brought by component failures and ensure a highly operational experience …

Optimization Of Pid Parameters Using Bbbc For A Multiarea Agc Scheme In A Deregulated Power System, Nagendra Kumar, Vishal Kumar, Barjeev Tyagi

Turkish Journal of Electrical Engineering and Computer Sciences

Automatic generation control (AGC) is an important service used for the secure and reliable operation of a power system. In this paper, a suitable AGC scheme for a deregulated environment has been studied for various load perturbation scenarios. A proportional integral derivative (PID) controller has been utilized to control the real power output of the generators. The optimal parameters of the PID controller have been determined using the big bang big crunch (BBBC) algorithm, (BBBC-PID). The performance of the BBBC-PID controller has been checked on three different sized multiarea power systems. The results obtained with the applied algorithm have also …

A Problem Approximation Surrogate Model (Pasm) For Fitness Approximation In Optimizing The Quantization Table For The Jpeg Baseline Algorithm, Vinoth Kumar Balasubramanian, Karpagam Manavalan

Turkish Journal of Electrical Engineering and Computer Sciences

The quantization table in the baseline Joint Photographic Experts Group (JPEG) algorithm plays an important role in compression/quality trade-off. Hence the detection of the optimal quantization table is viewed as an optimization problem. The genetic algorithm (GA) is an attractive optimization tool by many researchers for this application due to its ability in dealing with complex problems. In spite of its advantages, the GA requires more computation time to achieve an optimal solution if it has an expensive fitness evaluation. This paper proposes a problem approximation surrogate model (PASM) for fitness approximation to assist the GA in optimizing the quantization …

A Gis-Based Novel Active Monitoring System For Fiber Networks, Özer Koray Akdemi̇r, Taner Dursun, Sadik Arslan, Recep Benzer, Muhammet Ali̇ Akcayol

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a geographic information system (GIS)-based novel fiber network monitoring system has been developed to improve the operation and maintenance of fiber optic networks (FONs). The main aim of the developed system is to provide the required capabilities for both detailed digital modeling and central monitoring of FONs. The system can perform scheduled measurements and dispatch alarms if any fault or degradation is detected in the concerned FON. It also indicates the alarm locations on a map as a considerable contribution to decreasing mean time to repair. The developed monitoring system has more security features than others.

Optimization With Genetic Algorithm Of Temperature-Dependent Fiber Length Of L-Band Edfa Gain, Murat Yücel, Damt Adnan Mustafa Mustafa

Turkish Journal of Electrical Engineering and Computer Sciences

Erbium-doped fiber amplifiers (EDFAs) have great importance in long-distance communication. It is required to have equal gain for all signals that are transferred and to avoid loss in the receiver of long-distance communication systems. However, temperature dependence changes the output spectrum of the designed gain-flattening systems. In this study, each erbium-doped fiber (EDF) length of a two-stage L-band EDFA has been optimized using a genetic algorithm method; because of the temperature dependence of EDFAs, there is no general rule. Thus, a simple, fast, dynamic, and highly accurate model has been developed and obtained for different EDF lengths that will fix …

Gravitational Search Algorithm For Determining Controller Parameters In An Automatic Voltage Regulator System, Serhat Duman, Nuran Yörükeren, İsmai̇l Hakki Altaş

Turkish Journal of Electrical Engineering and Computer Sciences

proportional-integral-derivate (PID) controller for an automatic voltage regulator (AVR) system using a heuristic gravitational search algorithm (GSA) based on mass interactions and Newton's law of gravity. The determination of optimal controller parameters is considered an optimization problem in which different performance indexes and a performance criterion in the time domain have been used as objective functions to test the performance and effectiveness of the GSA. In the determining process of the parameters, the designed PID controller with the proposed approach is simulated under different conditions and the performance of the controller is compared with those reported in the literature. From …

Modeling And Performance Optimization Of Photovoltaic And Thermal Collector Hybrid System, Di̇lşad Engi̇n, Meti̇n Çolak

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the hybrid photovoltaic/thermal collector (PV/T) system's electrical and thermal efficiency was examined by stating a mathematical model and developing a prototype of the system. To enhance the electrical efficiency, the cell temperature of the PV module was decreased with cooling and the heated fluid could be used for low heating applications. For this purpose, a PV/T system was modeled and constructed using a thermal collector placed beneath the photovoltaic panel where the excess heat and solar radiation through the transparent PV module was the input of the thermal collector. A transparent solar module was used in order …

Optimization Design Of A Doubly Salient 8/6 Srm Based On Three Computational Intelligence Methods, Fares Rebahi, Amar Bentounsi, Houssem Rafik El-Hana Bouchekara, Redjem Rebbah

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this paper is to optimize an 8/6 doubly salient switched reluctance machine using three computational intelligence methods, which include particle swarm optimization, a genetic algorithm, and differential evolution. Three cases are investigated where different parameters are considered like the stator pole arc, rotor pole arc, and ratios, which define the stator yoke and rotor thickness. The objective functions considered are the average torque and the torque-to-weight functions. The simulations are carried out using MATLAB and FEMM software. The optimal results found are compared with the initial design, and it is shown that high improvements are achieved.

Optimal Power Flow With Svc Devices By Using The Artificial Bee Colony Algorithm, Kadi̇r Abaci, Volkan Yamaçli, Ali̇ Akdağli

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a simple and efficient heuristic search method based on the artificial bee colony (ABC) algorithm is presented and used for the optimal power flow (OPF) problem in power systems with static VAR compensator (SVC) devices. The total generation cost of a power system with SVC devices (which improve the voltage stability at load buses) is optimally minimized with the use of ABC. The ABC, which is based on the foraging behavior of honey bees searching for the best food source, is a recently proposed optimization algorithm. The performance of the presented ABC algorithm was tested and verified …

A New Deployment Method For Electric Vehicle Charging Infrastructure, Bünyami̇n Yağciteki̇n, Mehmet Uzunoğlu, Ari̇f Karakaş

Turkish Journal of Electrical Engineering and Computer Sciences

The fast depletion of fossil fuels, climate change, and global warming have become major worldwide problems and alternatives for conventional transportation have been actively researched in the last decade. Compared to available conventional vehicles, electric vehicles have a leading position due to their environmentally friendly transportation. Recent electric vehicle penetration brings the necessity of a high number of charging stations, which are considered to be established in community areas such as shopping centers, hospitals, commercial areas, university campuses, residential areas, and streets. Deployment planning of charging stations is very important for driver expectations and social and economic impacts of electric …

Energy-Efficient And Environmentally Friendly Power Dispatch By Trigeneration With Renewable Energy And Energy Storage, Faisal Pazheri, Mohd Fauzi Othman, Nazar H. Malik, Abdulrehman Ali Al-Arainy

Turkish Journal of Electrical Engineering and Computer Sciences

The importance of energy-efficient power generation that effectively utilizes the available fossil fuels is increasing due to the gradual decline in fossil fuel reserves. Furthermore, concern about global warming has led to rapid growth in renewable energy and energy storage technologies. This trend is encouraging power utilities to effectively exploit the use of renewable energy resources (RESs) and energy storage facilities (ESFs) for power supply systems. In this regards, trigeneration in the presence of RESs and ESFs can play an important role for efficient and clean power dispatch. This paper discusses the optimum power dispatch using a hybrid power plant …