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Full-Text Articles in Physical Sciences and Mathematics

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 …


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 …


Composite Power System Adequacy Assessment Based On Postoptimal Analysis, Amir Safdarian, Mahmood Fotuhi-Firuzabad, Farrokh Aminifar Jan 2013

Composite Power System Adequacy Assessment Based On Postoptimal Analysis, Amir Safdarian, Mahmood Fotuhi-Firuzabad, Farrokh Aminifar

Turkish Journal of Electrical Engineering and Computer Sciences

The modeling and evaluation of enormous numbers of contingencies are the most challenging impediments associated with composite power system adequacy assessment, particularly for large-scale power systems. Optimal power flow (OPF) solution, as a widely common approach, is normally employed to model and analyze each individual contingency as an independent problem. However, mathematical representations associated with diverse states are slightly different in one or a few generating units, line outages, or trivial load variations. This inherent attribute brings a promising idea to speed up the contingency evaluation procedure. In this paper, postoptimal analysis (POA), as a well-recognized technique to attack a …


Modified Iterated Extended Kalman Particle Filter For Single Satellite Passive Tracking, Panlong Wu, Jianshou Kong, Yuming Bo Jan 2013

Modified Iterated Extended Kalman Particle Filter For Single Satellite Passive Tracking, Panlong Wu, Jianshou Kong, Yuming Bo

Turkish Journal of Electrical Engineering and Computer Sciences

Single satellite-to-satellite passive tracking techniques have great significance in space surveillance systems. A new passive modified iterated extended Kalman particle filter (MIEKPF) using bearings-only measurements in the Earth-Centered Inertial Coordinate System is proposed. The modified iterated extended Kalman filter (MIEKF), with a new maximum likelihood iteration termination criterion, is used to generate the proposal distribution of the MIEKPF. Moreover, a new measurement update equation of the MIEKF is derived by modifying the objective function of the Gauss--Newton iteration. The approximated second-order linearized state propagation equation, Jacobian matrix of state transfer, and measurement equations are derived in satellite 2-body movement. The …


A Bacterial Foraging Optimization Approach For Tuning Type-2 Fuzzy Logic Controller, Mohammad Kiani, Seyed Mohammad Ali Mohammadi, Ali Akbar Gharaveisi Jan 2013

A Bacterial Foraging Optimization Approach For Tuning Type-2 Fuzzy Logic Controller, Mohammad Kiani, Seyed Mohammad Ali Mohammadi, Ali Akbar Gharaveisi

Turkish Journal of Electrical Engineering and Computer Sciences

The type-1 fuzzy sets theory was proposed to handle uncertainty in control systems, but some cases showed some liabilities of type-1 fuzzy sets when faced with unpredictable disturbance and uncertainties. Therefore, type-2 fuzzy sets were introduced and extended while providing more degrees of freedom in designing criteria. The most important specification of type-2 fuzzy sets is the interval between a superior membership function and an inferior membership function, which is called the footprint of uncertainty. This paper presents a bacterial foraging optimization approach for optimizing the parameterized membership function. The above criterion is applied to an automatic voltage regulator system …


A Method For Ontology-Based Semantic Relatedness Measurement, Görkem Gi̇ray, Murat Osman Ünalir Jan 2013

A Method For Ontology-Based Semantic Relatedness Measurement, Görkem Gi̇ray, Murat Osman Ünalir

Turkish Journal of Electrical Engineering and Computer Sciences

There are many methods having different approaches for assessing similarity and relatedness and they are used in many application areas, including web service discovery, invocation and composition, word sense disambiguation, information retrieval, ontology alignment and merging, document clustering, and short answer grading. These methods can be categorized as path-based, information content-based, feature-based, geometric model-based, and hybrid approaches. These approaches use resources such as concept hierarchy, conceptual graph, and corpus for computing similarity and relatedness. With the rise of the semantic web, ontologies have attracted the attention of several researchers. Ontologies represented in the Web Ontology Language (OWL) are also valuable …


End-To-End Transmission Time-Based Opportunistic Routing Protocols For Bus Networks, Luobei Kuang, Zhijun Wang, Ming Xu, Yingwen Cheng Jan 2013

End-To-End Transmission Time-Based Opportunistic Routing Protocols For Bus Networks, Luobei Kuang, Zhijun Wang, Ming Xu, Yingwen Cheng

Turkish Journal of Electrical Engineering and Computer Sciences

Single path routing protocols for Internet access in bus networks (composed of traveling city public buses) may not achieve satisfactory performance because of frequent bus mobility. This paper studies the opportunistic routing protocols in bus networks to improve the system throughput and reduce the access delay. In this paper, we first propose an end-to-end transmission time (EET)-based opportunistic routing (OR) framework. We then derive 3 EET-based OR protocols, EETOR (EET-based OR), EETMcOR (EET-based OR with MAC contention consideration), and EETCcOR (EET-based OR with congestion control consideration), which consider 3 different EET metrics. EETOR considers the network layer transmission behavior to …


7-Dof Haptic Device And Interface Design, Özgür Başer, Erhan İlhan Konukseven Jan 2013

7-Dof Haptic Device And Interface Design, Özgür Başer, Erhan İlhan Konukseven

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the developed 7-DOF haptic device (HaP-7) and its virtual reality interface are presented. The design issues, design constraints, and alternative design configurations are discussed and the potential advantages of the HaP-7 are put forward. The kinematic model of the proposed device looks like a simplified human arm kinematic model. The redundant characteristic of the device provides larger workspace and allows for appropriate posture selection for the purposes of maximization of the rigidity, transparency and stability, while minimizing the inertia and power consumption in addition to the singularity and obstacle avoidance optimization.


Actor-Critic-Based Ink Drop Spread As An Intelligent Controller, Hesam Sagha, Iman Esmaili Paeen Afrakoti, Saeed Bagherishouraki Jan 2013

Actor-Critic-Based Ink Drop Spread As An Intelligent Controller, Hesam Sagha, Iman Esmaili Paeen Afrakoti, Saeed Bagherishouraki

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces an innovative adaptive controller based on the actor-critic method. The proposed approach employs the ink drop spread (IDS) method as its main engine. The IDS method is a new trend in soft-computing approaches that is a universal fuzzy modeling technique and has been also used as a supervised controller. Its process is very similar to the processing system of the human brain. The proposed actor-critic method uses an IDS structure as an actor and a 2-dimensional plane, representing control variable states, as a critic that estimates the lifetime goodness of each state. This method is fast, simple, …


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 …


Optimal Placement Of Pmus Using Improved Tabu Search For Complete Observability And Out-Of-Step Prediction, Amany El Zonkoly, Samah El Safty, Rana Maher Jan 2013

Optimal Placement Of Pmus Using Improved Tabu Search For Complete Observability And Out-Of-Step Prediction, Amany El Zonkoly, Samah El Safty, Rana Maher

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes an optimization method for the optimal placement of phasor measurement units (PMUs) for the complete observability of power systems. The proposed method is based on numerical observability and artificial intelligence. The artificial intelligence algorithm used is the improved tabu search (ITS) algorithm. The ITS is used to find the optimal placement for the PMU to keep the system completely observable. In addition, the paper describes a predictive out-of-step (OOS) algorithm based on the observation of the voltage phase difference between the substations. The proposed optimal placement of the PMUs and the OOS algorithm is tested using the …


Optimized Features Selection For Gender Classification Using Optimization Algorithms, Sajid Ali Khan, Muhammad Nazir, Naveed Riaz Jan 2013

Optimized Features Selection For Gender Classification Using Optimization Algorithms, Sajid Ali Khan, Muhammad Nazir, Naveed Riaz

Turkish Journal of Electrical Engineering and Computer Sciences

Optimized feature selection is an important task in gender classification. The optimized features not only reduce the dimensions, but also reduce the error rate. In this paper, we have proposed a technique for the extraction of facial features using both appearance-based and geometric-based feature extraction methods. The extracted features are then optimized using particle swarm optimization (PSO) and the bee algorithm. The geometric-based features are optimized by PSO with ensemble classifier optimization by the genetic algorithm. Using this approach, we have obtained promising results in terms of the classification error rate and computation time minimization. Moreover, our optimized feature-based method …


Bidding Strategy Of Generation Companies In A Competitive Electricity Market Using The Shuffled Frog Leaping Algorithm, Vijaya Kumar Jonnalagadda, Vinod Kumar Dulla Mallesham Jan 2013

Bidding Strategy Of Generation Companies In A Competitive Electricity Market Using The Shuffled Frog Leaping Algorithm, Vijaya Kumar Jonnalagadda, Vinod Kumar Dulla Mallesham

Turkish Journal of Electrical Engineering and Computer Sciences

In a competitive electricity market, generation companies need suitable bidding models to maximize their profit. Therefore, each supplier will bid strategically for choosing the bidding coefficients to counter the competitors' bidding strategies. In this paper, the optimal bidding strategy problem is solved using a novel algorithm based on the shuffled frog leaping algorithm (SFLA). It is a memetic metaheuristic that is designed to seek a global optimal solution by performing a heuristic search. It combines the benefits of the genetic-based memetic algorithm (MA) and the social behavior-based particle swarm optimization (PSO). This allows it to have a more precise search …


Interaction Analysis Of Multi-Function Facts And D-Facts Controllers By Mrga, Maghsood Mokhtari, Javad Khazaie, Daryoush Nazarpour, Morteza Farsadi Jan 2013

Interaction Analysis Of Multi-Function Facts And D-Facts Controllers By Mrga, Maghsood Mokhtari, Javad Khazaie, Daryoush Nazarpour, Morteza Farsadi

Turkish Journal of Electrical Engineering and Computer Sciences

With the growing application of flexible AC transmission systems (FACTS) and distributed FACTS (D-FACTS), the coordinating problem of FACTS and D-FACTS controllers in joint operation must be considered in modern power systems. The main purpose of this paper is to investigate the possible interaction that may occur between the distributed static series compensator (DSSC) and the static synchronous compensator (STATCOM) when they operate concurrently in the power system. The modified relative gain array (MRGA) is implemented to analyze the interactions. The application of MRGA for the effective design of multiobjective controllers of the STATCOM and DSSC is demonstrated by 2 …


Using The Csm And Vsm Techniques To Speed Up The Ica Algorithm Without A Loss Of Quality, Mahdi Mahdikhani, Mohammad Hosein Kahaei Jan 2013

Using The Csm And Vsm Techniques To Speed Up The Ica Algorithm Without A Loss Of Quality, Mahdi Mahdikhani, Mohammad Hosein Kahaei

Turkish Journal of Electrical Engineering and Computer Sciences

In blind source separation problems that are implemented based on the independent component analysis (ICA) algorithm, the separation speed and quality are related inversely. In this paper, the proposed algorithms eliminate this tradeoff by generating a faster separation while maintaining the quality. In the proposed algorithms, in each frequency bin and in all of the learning steps, the separation quality of the separating matrix is compared with another one that we define as a situated matrix, and the best matrix is considered as an initial separating matrix in the next learning step. In this paper, we propose 2 algorithms based …


Simulation Of Discrete Electromagnetic Propagation Model For Atmospheric Effects On Mobile Communication, Şaban Seli̇m Şeker, Fulya Kunter Jan 2013

Simulation Of Discrete Electromagnetic Propagation Model For Atmospheric Effects On Mobile Communication, Şaban Seli̇m Şeker, Fulya Kunter

Turkish Journal of Electrical Engineering and Computer Sciences

Wireless communication has become an important part of our lives, and atmospheric effects are one of the ultimate factors affecting quality of communication and satellite systems. In this study the attenuation in mobile communication due to atmospheric events like snow and rain is simulated using the discrete propagation model. In this work, spherical raindrop and oblate spheroid raindrop modeling are used. To check the validity of simulations, the commonly used and accepted ITU-R rain model is used. Oblate spheroid raindrop modeling produces results that are more compatible with ITU-R results, especially at frequencies higher than 50 GHz. At lower frequencies, …


A 5-Bit 5 Gs/S Flash Adc Using Multiplexer-Based Decoder, Oktay Aytar, Ali̇ Tangel, Kudret Şahi̇n Jan 2013

A 5-Bit 5 Gs/S Flash Adc Using Multiplexer-Based Decoder, Oktay Aytar, Ali̇ Tangel, Kudret Şahi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a 5-bit flash analog-to-digital converter design using the 0.18-\mu m Taiwan Semiconductor Manufacturing Company's CMOS technology library. The designed system consists of 2 main blocks, a comparator array, and a digital decoder. The digital decoder contains a latch, 1-of-N decoder, and fat-tree encoder units. The 1-of-N decoder is implemented using 2 \times 1 multiplexers. As a result, the active die area and the power consumption are reduced, in addition to an increase in the sampling frequency. The power supply voltage range for the overall system is \pm 0.9 V. For testing purposes, a ramp signal of between …


Fuzzified Artificial Bee Colony Algorithm For Nonsmooth And Nonconvex Multiobjective Economic Dispatch Problem, Chandrasekaran Koodalsamy, Sishaj Pulikottil Simon Jan 2013

Fuzzified Artificial Bee Colony Algorithm For Nonsmooth And Nonconvex Multiobjective Economic Dispatch Problem, Chandrasekaran Koodalsamy, Sishaj Pulikottil Simon

Turkish Journal of Electrical Engineering and Computer Sciences

The economic dispatch (ED) problem is one of the important optimization problems in power system operation. Recently the power system has stressed the need for reliable, nonpolluting, and economic operation. Hence, 3 conflicting functions of reliability, emission, and fuel cost are considered in the objective function of the proposed ED problem. The problem is formulated as a nonsmooth and nonconvex problem when the valve-point effects of thermal units are considered in the proposed reliable emission and economic dispatch (REED) problem. This paper presents a multiobjective optimization methodology for solving the newly developed REED problem using a fuzzified artificial bee colony …


Design Of Information Retrieval Experiments: The Sufficient Topic Set Size For Providing An Adequate Level Of Confidence, Beki̇r Taner Di̇nçer Jan 2013

Design Of Information Retrieval Experiments: The Sufficient Topic Set Size For Providing An Adequate Level Of Confidence, Beki̇r Taner Di̇nçer

Turkish Journal of Electrical Engineering and Computer Sciences

In the current design of information retrieval (IR) experiments, a sample of 50 topics is generally agreed to be sufficient in size to perform dependable system evaluations. This article presents the detailed and formal explanation of how the second fundamental theorem of probability, the central limit theorem, can be used for the estimation of the sufficient size of a topic sample. The research performed in this article, using past Text Retrieval Conference data, reveals that, on average, 50 topics will be sufficient to provide a confidence level at or above 95% if the null hypothesis of an equal population mean …


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.


Simulation Of A Large Electric Distribution System Having Intensive Harmonics In The Industrial Zone Of Konya, Hasan Eroğlu, Musa Aydin Jan 2013

Simulation Of A Large Electric Distribution System Having Intensive Harmonics In The Industrial Zone Of Konya, Hasan Eroğlu, Musa Aydin

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, measurements were taken at different points of a sample distribution system in order to analyze the levels of harmonics that appear as a day-to-day increasing problem in electrical distribution systems. According to the measurement values, the dominant harmonics have been determined and an electrical model of the system has been prepared using the SimPowerSystems toolbox from MATLAB and Simulink. The accuracy of the electrical model has been verified by the measurement and simulation values. In addition, the transformer connection types' and impedances' simulations have been presented to understand and solve the harmonic problems in electrical distribution systems. …


A Computer-Aided Diagnosis System For Breast Cancer Detection By Using A Curvelet Transform, Nebi̇ Gedi̇k, Ayten Atasoy Jan 2013

A Computer-Aided Diagnosis System For Breast Cancer Detection By Using A Curvelet Transform, Nebi̇ Gedi̇k, Ayten Atasoy

Turkish Journal of Electrical Engineering and Computer Sciences

The most common type of cancer among women worldwide is breast cancer. Early detection of breast cancer is very important to reduce the fatality rate. For the hundreds of mammographic images scanned by a radiologist, only a few are cancerous. While detecting abnormalities, some of them may be missed, as the detection of suspicious and abnormal images is a recurrent mission that causes fatigue and eyestrain. In this paper, a computer-aided diagnosis system using the curvelet transform (CT) algorithm is proposed for interpreting mammograms to improve the decision making. The purpose of this study is to develop a method for …


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. …