Open Access. Powered by Scholars. Published by Universities.®

Computer Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 163

Full-Text Articles in Computer Engineering

A Practical Disturbance Generator To Test Performances Of Various Power Quality Mitigation Devices, Ahmet Teke, Mehmet Emi̇n Meral, Mehmet Tümay, Mehmet Uğraş Cuma Jan 2013

A Practical Disturbance Generator To Test Performances Of Various Power Quality Mitigation Devices, Ahmet Teke, Mehmet Emi̇n Meral, Mehmet Tümay, Mehmet Uğraş Cuma

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a practical thyristor-based 3-phase sag/swell/outage generator (disturbance generator) is designed to test various power quality mitigation devices (PQMDs), such as solid state transfer switch (SSTS), static voltage compensator (SVC), and uninterruptible power supply. The latest technological disturbance generators (DGs) and the proposed DG are comprehensively discussed and compared with focus on usefulness, economic aspects, and simplicity. The proposed DG is used for experimentally generating different fault conditions and testing a SSTS. The comparisons and analyses show that the proposed DG is an optimum and simple solution to generate sag, swell, unbalance, overvoltage, undervoltage, and outage to test …


Optimal Release Policies For A Software System With Warranty Cost And Change-Point Phenomenon, D.R. Prince Williams Jan 2013

Optimal Release Policies For A Software System With Warranty Cost And Change-Point Phenomenon, D.R. Prince Williams

Turkish Journal of Electrical Engineering and Computer Sciences

Determining the software quality and release time of the software is an important role of software reliability. Software reliability growth models (SRGMs) are applications of software reliability. The change-point is defined as the prominent change in the software testing time, in connection with the quality of a software error occurrence or error-detection phenomenon. As a result, the software reliability growth process, based on the change-point, affects the precision of the software reliability prediction, based on the SRGMs. To find the accurate total expected delivery cost with a suitable warranty period of the software system, a new cost model for the …


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 …


Novel Control Strategy For Voltage Source Converters Based On Energy Function, Sanaz Namayan Tavana, Gevork Gharehpetian, Mehrdad Abedi, Ali Bidadfar Jan 2013

Novel Control Strategy For Voltage Source Converters Based On Energy Function, Sanaz Namayan Tavana, Gevork Gharehpetian, Mehrdad Abedi, Ali Bidadfar

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a nonlinear control strategy for pulse-width modulated voltage source converters (VSCs). A passivity-based approach, resulting from the Lyapunov direct method, is presented for designing an effective nonlinear VSC controller to improve their dynamic behaviors under perturbed conditions. The differential equations of the converters are obtained and then transformed into a d-q frame. Considering the nonlinearity of the transformed equations, the Lyapunov direct method is utilized to find a solution to improve the transient response. The time derivative of the Lyapunov function guarantees that increasing its dissipative term will result in the trajectory of the VSC system returning …


Anticipating The Friction Coefficient Of Friction Materials Used In Automobiles By Means Of Machine Learning Without Using A Test Instrument, Mustafa Ti̇mur, Fati̇h Aydin Jan 2013

Anticipating The Friction Coefficient Of Friction Materials Used In Automobiles By Means Of Machine Learning Without Using A Test Instrument, Mustafa Ti̇mur, Fati̇h Aydin

Turkish Journal of Electrical Engineering and Computer Sciences

The most important factor for designs in which friction materials are used is the coefficient of friction. The coefficient of friction has been determined taking such variants as velocity, temperature, and pressure into account, which arise from various factors in friction materials, and by analyzing the effects of these variants on friction materials. Many test instruments have been produced in order to determine the coefficient of friction. In this article, a study about the use of machine learning algorithms instead of test instruments in order to determine the coefficient of friction is presented. Isotonic regression was selected as the machine …


Adaptive Control Of A Time-Varying Rotary Servo System Using A Fuzzy Model Reference Learning Controller With Variable Adaptation Gain, Ömer Aydoğdu, Özdemi̇r Alkan Jan 2013

Adaptive Control Of A Time-Varying Rotary Servo System Using A Fuzzy Model Reference Learning Controller With Variable Adaptation Gain, Ömer Aydoğdu, Özdemi̇r Alkan

Turkish Journal of Electrical Engineering and Computer Sciences

The constant parameters in a conventional fuzzy controller lead to a poor performance for time-varying systems. In this study, a fuzzy model reference learning controller (FMRLC) with a newly defined variable adaptation gain is designed and implemented in the adaptive fuzzy control of a time-varying rotary servo (TVRS) system. In the design of the FMRLC, a knowledge-base modification algorithm with variable adaptation gain is used instead of a fuzzy relation table. Hence, it is provided that the learning and adaptation mechanism continuously updates the knowledge base of the adaptive fuzzy controller against any parameter variations, such as changing loads. By …


Optimized Operation And Maintenance Costs To Improve System Reliability By Decreasing The Failure Rate Of Distribution Lines, Hamed Hashemi Dezaki, Seyed Hossein Hosseinian, Hossein Askarian Abyaneh, Seyed Mohammad Mousavi Agah Jan 2013

Optimized Operation And Maintenance Costs To Improve System Reliability By Decreasing The Failure Rate Of Distribution Lines, Hamed Hashemi Dezaki, Seyed Hossein Hosseinian, Hossein Askarian Abyaneh, Seyed Mohammad Mousavi Agah

Turkish Journal of Electrical Engineering and Computer Sciences

Improving distribution system reliability has received a great deal of attention in recent years. Because of the limitation in expected budgets, it is desirable to determine the most efficient strategy to improve system reliability. This paper proposes a novel method to determine the optimized operation and maintenance costs in order to decrease the failure of system components. The proposed objective function includes the average system frequency interruption index (ASIFI) value. To achieve the best strategy to decrease failures of system components, it is necessary to find the minimum value of the objective function, considering the constraints of operation and maintenance …


Model Of A Photovoltaic Panel Emulator In Matlab-Simulink, Hayretti̇n Can Jan 2013

Model Of A Photovoltaic Panel Emulator In Matlab-Simulink, Hayretti̇n Can

Turkish Journal of Electrical Engineering and Computer Sciences

Being able to behave electrically similar to photovoltaic (PV) panels, PV emulator systems make it possible to perform different PV system tests under various operation conditions. In this paper, a model of a PV panel emulator is presented using the Power System Blockset under MATLAB-Simulink. The simulation of the emulator system is developed for testing a controller prior to a real-time implementation. The model can handle the dependence of all of the parameters in the model with respect to solar radiation and temperature. The simulation results show that the output characteristics of the simulator have good agreement with those of …


Performance Evolution Of A Newly Developed General-Use Hybrid Ais-Ann System: Aaa-Response, Seral Özşen, Sali̇h Güneş Jan 2013

Performance Evolution Of A Newly Developed General-Use Hybrid Ais-Ann System: Aaa-Response, Seral Özşen, Sali̇h Güneş

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we have developed a nonlinear recognition system in the artificial immune systems (AIS) field named `AaA-response (artificial neural network (ANN)-aided AIS-response)', which is different from previous AIS methods in that it uses a different modeling strategy in the formation of the memory response. Because it also uses ANNs in the determination of the correct output, it can be seen as a hybrid system that involves AIS and ANN approaches. Unlike the other AIS methods, AaA-response uses multiple system units (or antibodies) to form an output for a presented input. This property gives the proposed system the ability …


Improving Power Systems Operation Through Multiobjective Optimal Location Of Optimal Unified Power Flow Controller, Afshin Lashkar Ara, Ahad Kazemi, Mohammad Behshad Jan 2013

Improving Power Systems Operation Through Multiobjective Optimal Location Of Optimal Unified Power Flow Controller, Afshin Lashkar Ara, Ahad Kazemi, Mohammad Behshad

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a multiobjective optimization methodology to find the optimal location for an optimal unified power flow controller (OUPFC) device. Moreover, the installation cost function of the OUPFC device is developed. The objective functions are the total fuel cost, power losses, and system loadability with and without the minimum cost of the OUPFC installation. The \varepsilon-constraint approach is implemented for the multiobjective mathematical programming formulation. The proposed algorithm is implemented in the IEEE 30- and 118-bus test systems. The solution procedure uses nonlinear programming to optimally locate the OUPFC incorporated in an optimal power flow problem considering these objective …


Artificial Immunity-Based Induction Motor Bearing Fault Diagnosis, Hakan Çaliş, Abdülkadi̇r Çakir, Emre Dandil Jan 2013

Artificial Immunity-Based Induction Motor Bearing Fault Diagnosis, Hakan Çaliş, Abdülkadi̇r Çakir, Emre Dandil

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the artificial immunity of the negative selection algorithm is used for bearing fault detection. It is implemented in MATLAB-based graphical user interface software. The developed software uses amplitudes of the vibration signal in the time and frequency domains. Outer, inner, and ball defects in the bearings of the induction motor are detected by anomaly monitoring. The time instants of the fault occurrence and fault level are determined according to the number of activated detectors. Anomaly detection in the frequency domain is implemented by monitoring the fault indicator bearing frequencies and harmonics, calculated using the bearing dimensions and …


System Designs To Perform Bioinformatics Sequence Alignment, Çağlar Yilmaz, Mustafa Gök Jan 2013

System Designs To Perform Bioinformatics Sequence Alignment, Çağlar Yilmaz, Mustafa Gök

Turkish Journal of Electrical Engineering and Computer Sciences

The emerging field of bioinformatics uses computing as a tool to understand biology. Biological data of organisms (nucleotide and amino acid sequences) are stored in databases that contain billions of records. In order to process the vast amount of data in a reasonable time, high-performance analysis systems are developed. The main operation shared by the analysis tools is the search for matching patterns between sequences of data (sequence alignment). In this paper, we present 2 systems that can perform pairwise and multiple sequence alignment operations. Through the optimized design methods, proposed systems achieve up to 3.6 times more performance compared …


An Improved Hybrid Approach For The Plc-Based Implementation Of Reduced Rw Supervisors, Murat Uzam, Gökhan Gelen Jan 2013

An Improved Hybrid Approach For The Plc-Based Implementation Of Reduced Rw Supervisors, Murat Uzam, Gökhan Gelen

Turkish Journal of Electrical Engineering and Computer Sciences

A successful application of a hybrid (mixed Petri net/automaton) approach for the real-time supervisory control of an experimental manufacturing system was reported recently. The hybrid approach includes a Ramadge--Wonham (RW) supervisor in the form of an automaton. The reduced RW supervisor offers fewer states for the programmable logic controller (PLC) implementation of the hybrid controller with less memory requirements, but due to a problem called the avalanche effect, the PLC implementation of the hybrid controller with the reduced RW supervisor was not possible. This paper proposes a method to both detect and eliminate the avalanche effect problem for a RW …


A Framework For Medical Image Retrieval Using Merging-Based Classification With Dependency Probability-Based Relevance Feedback, Hossein Pourghassem, Sabalan Daneshvar Jan 2013

A Framework For Medical Image Retrieval Using Merging-Based Classification With Dependency Probability-Based Relevance Feedback, Hossein Pourghassem, Sabalan Daneshvar

Turkish Journal of Electrical Engineering and Computer Sciences

Content-based image retrieval (CBIR) systems are used to retrieve relevant images from large-scale databases. In this paper, a framework for the image retrieval of a large-scale database of medical X-ray images is presented. This framework is designed based on query image classification into several prespecified homogeneous classes. Using a merging scheme and an iterative classification, the homogeneous classes are formed from overlapping classes in the database. For this purpose, the shape and texture features, selected using the forward selection algorithm, are optimized by a novel genetic algorithm-based feature reduction and optimization algorithm in the feature space. In this algorithm, using …


A Blind Digital Signature Scheme Using Elliptic Curve Digital Signature Algorithm, İsmai̇l Bütün, Mehmet Demi̇rer Jan 2013

A Blind Digital Signature Scheme Using Elliptic Curve Digital Signature Algorithm, İsmai̇l Bütün, Mehmet Demi̇rer

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we propose a blind digital signature (BDS) scheme based on the elliptic curve digital signature algorithm that increases the performance significantly. The security of our scheme is based on the difficulty of the elliptic curve discrete algorithm problem. Therefore, it offers much smaller key lengths for the desired security levels, along with much faster cryptographic processes, leading to fewer hardware and software requirements. According to our simulation results, the relative performance improvement of our proposed BDS scheme is up to 96% when compared with previously proposed schemes.


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 …


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 …


Hybrid Of Genetic Algorithm And Great Deluge Algorithm For Rough Set Attribute Reduction, Najmeh Sadat Jaddi, Salwani Abdullah Jan 2013

Hybrid Of Genetic Algorithm And Great Deluge Algorithm For Rough Set Attribute Reduction, Najmeh Sadat Jaddi, Salwani Abdullah

Turkish Journal of Electrical Engineering and Computer Sciences

The attribute reduction problem is the process of reducing unimportant attributes from a decision system to decrease the difficulty of data mining or knowledge discovery tasks. Many algorithms have been used to optimize this problem in rough set theory. The genetic algorithm (GA) is one of the algorithms that has already been applied to optimize this problem. This paper proposes 2 kinds of memetic algorithms, which are a hybridization of the GA, with 2 versions (linear and nonlinear) of the great deluge (GD) algorithm. The purpose of this hybridization is to investigate the ability of this local search algorithm to …


A Low-Voltage And Low-Power Sinh-Domain Universal Biquadratic Filter For Low-Frequency Applications, Farooq Khanday, Nisar Shah Jan 2013

A Low-Voltage And Low-Power Sinh-Domain Universal Biquadratic Filter For Low-Frequency Applications, Farooq Khanday, Nisar Shah

Turkish Journal of Electrical Engineering and Computer Sciences

Sinh-domain CMOS filters have favorable properties, such as a wide dynamic range at low supply voltage, compactness, linearity, and low power consumption. These properties are becoming increasingly important for biomedical applications that require extremely low-power dissipation and neuromorphic circuits that attempt to reproduce the biophysics of biological neurons and synapses. In this paper, a low-voltage sinh-domain universal biquadratic filter circuit is introduced. The circuit, aside from permitting the independent adjustment of pole frequency (\omega_0) and the quality factor (Q), is free from matching conditions, capable of absorbing the shunt parasitic capacitances, amenable for monolithic integration, and composed of merely a …


Control Of Diesel Engines Mounted On Vehicles In Mobile Cranes Via Can Bus, Muci̇z Özcan, Hi̇dayet Günay Jan 2013

Control Of Diesel Engines Mounted On Vehicles In Mobile Cranes Via Can Bus, Muci̇z Özcan, Hi̇dayet Günay

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the aim was to lift loads that required more force using the infrastructure of existing vehicles. To this end, a truck-mounted diesel engine was selected to be used in mobile crane applications. A control system was designed and implemented to obtain the appropriate hydraulic force by accessing the diesel engine with a controller area network bus via an electronic control unit (ECU). For this purpose, hydraulic pumps to be used to operate the crane were mounted on the selected mobile diesel engine with an ECU. Firms that manufacture cranes in the world produce cranes with infrastructure. This …


Stopping Spam With Sending Session Verification, Ahmet Baran Jan 2013

Stopping Spam With Sending Session Verification, Ahmet Baran

Turkish Journal of Electrical Engineering and Computer Sciences

Spam has become one of the most significant problems for Internet communication and users today. The traditional filtering methods and signature-based spam blocking systems that have come into prominence recently fall short, as statistics demonstrate that spam further mounts up day after day. In this study, a new method is recommended to block spam mails. In this recommended method, a mail sending session is verified during mail envelope communication by adding small attachments to the simple mail transfer protocol, so spam mails can be blocked before leaving the sender domain or relay machine. Additionally, hijacked user accounts are able to …


Flow Velocity Measurement And Analysis Based On Froth Image Sift Features And Kalman Filter For Froth Flotation, Jinping Liu, Weihua Gui, Zhaohui Tang Jan 2013

Flow Velocity Measurement And Analysis Based On Froth Image Sift Features And Kalman Filter For Froth Flotation, Jinping Liu, Weihua Gui, Zhaohui Tang

Turkish Journal of Electrical Engineering and Computer Sciences

The flow velocity of flotation froth involves important information about the concentrate grade and the mineral recovery. It is significant to maintain the flow velocity of the froth at proper levels to achieve a good production performance in the machine vision-based process monitoring and control. However, the accurate velocity field measurement for the heavily deformed and seriously fragile froth bubbles is still a great challenge. Scale-invariant feature transform (SIFT) feature-based image matching provides an effective registration method for deformed objects, but most of the processing time would be wasted on the feature extraction and matching in irrelevant regions of the …


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 …


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 …


A Temporal Xml Data Model In Anaesthesia Information Systems, Oya Ünlü Duygulu, Taflan İmre Gündem Jan 2013

A Temporal Xml Data Model In Anaesthesia Information Systems, Oya Ünlü Duygulu, Taflan İmre Gündem

Turkish Journal of Electrical Engineering and Computer Sciences

Time information is an important aspect of a health information system. Health information cannot be represented and queried correctly without time in medical research, auditing, and medicolegal cases. Extensible Markup Language (XML) is being used in health information systems and has been formerly proposed as a data model for anaesthesia information systems. In this paper, we propose incorporating time into an XML model for anaesthesia information systems. A new storage structure and a temporal index structure are proposed in order to store temporal XML data and process time queries efficiently. In our proposed model, time has 4 dimensions: valid time, …


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 …


Big Bang-Big Crunch Optimization Algorithm With Local Directional Moves, Hakki Murat Genç, İbrahi̇m Eksi̇n, Osman Kaan Erol Jan 2013

Big Bang-Big Crunch Optimization Algorithm With Local Directional Moves, Hakki Murat Genç, İbrahi̇m Eksi̇n, Osman Kaan Erol

Turkish Journal of Electrical Engineering and Computer Sciences

The big bang--big crunch (BB--BC) algorithm has been proposed as a novel optimization method that relies on one of the theories of the evolution of the universe, namely the big bang and big crunch theory. It has been shown that this algorithm is capable of quick convergence, even in long, narrow parabolic-shaped flat valleys or in the existence of several local extremes. In this work, the BB--BC optimization algorithm is hybridized with local search moves in between the ``banging'' and ``crunching'' phases of the algorithm. These 2 original phases of the BB--BC algorithm are preserved, but the representative point (``best'' …


Review Of Distinctive Phonetic Features And The Arabic Share In Related Modern Research, Yousef Alotaibi, Ali Meftah Jan 2013

Review Of Distinctive Phonetic Features And The Arabic Share In Related Modern Research, Yousef Alotaibi, Ali Meftah

Turkish Journal of Electrical Engineering and Computer Sciences

Most research in the field of digital speech technology has traditionally been conducted in only a few languages, such as English, French, Spanish, or Chinese. Numerous studies using distinctive phonetic features (DPFs) with different techniques and algorithms have been carried out during the last 3 decades, mainly in English, Japanese, and other languages of industrialized countries. DPF elements are based on a technique used by linguists and digital speech and language experts to distinguish between different phones by considering the lowest level of actual features during phonation. These studies have investigated the best performances, outcomes, and theories, especially those regarding …


A Learning Approach In Link Adaptation For Mimo-Ofdm Systems, Hali̇l Yi̇ği̇t, Adnan Kavak Jan 2013

A Learning Approach In Link Adaptation For Mimo-Ofdm Systems, Hali̇l Yi̇ği̇t, Adnan Kavak

Turkish Journal of Electrical Engineering and Computer Sciences

We propose a neural network (NN)-based adaptive modulation and coding (AMC) for link adaptation in MIMO-OFDM systems. The AMC optimizes the best modulation and coding scheme (MCS) under a packet error rate (PER) constraint. In our approach, a NN with a multilayer perceptron (MLP) structure is applied for the AMC and its performance is compared with the k-nearest neighbor (k-NN) algorithm under the frequency-flat (1-tap) and frequency-selective (4-tap) wireless channel conditions. The simulation results show that the NN classifier outperforms the k-NN algorithm, especially in terms of the PER, due to the fact that the MLP guarantees a MCS with …


Economic Power Dispatch Of Power Systems With Pollution Control Using Artificial Bee Colony Optimization, Linda Slimani, Tarek Bouktir Jan 2013

Economic Power Dispatch Of Power Systems With Pollution Control Using Artificial Bee Colony Optimization, Linda Slimani, Tarek Bouktir

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a solution for the emission-controlled economic dispatch (ECED) problem of medium-sized power systems via an artificial bee colony algorithm. The ECED problem, which accounts for the minimization of both the fuel cost and the emission, is a multiple objective function problem. The objective is to minimize the total fuel cost of the generation and environmental pollution caused by fossil-based thermal generating units and to also maintain an acceptable system performance in terms of the limits on the generator's real and reactive power outputs, bus voltages, shunt capacitors/reactors, and power flow of transmission lines. The proposed algorithm is …