Dynamics, Stability, And Actuation Methods For Powered Compass Gait Walkers,
2014
TÜBİTAK
Dynamics, Stability, And Actuation Methods For Powered Compass Gait Walkers, Koray Kadi̇r Şafak
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, methods to achieve actively powered walking on level ground using a simple 2-dimensional walking model (compass-gait walker) are explored. The walker consists of 2 massless legs connected at the hip joint, a point mass at the hip, and an infinitesimal point mass at the feet. The walker is actuated either by applying equal joint torques at the hip and ankle, by an impulse applied at the toe off, immediately before the heel strike, or by the combination of both. It is shown that actuating the walker by equal joint torques at the hip and ankle on level …
Statistical Approach For Determining Impulse Breakdown Voltage Distribution Under Dc Sweep Voltage,
2014
TÜBİTAK
Statistical Approach For Determining Impulse Breakdown Voltage Distribution Under Dc Sweep Voltage, Mehmet Demi̇r, Celal Koraşli
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a comprehensive approach to the statistical characterization of impulse breakdown voltage under the effect of a DC sweep voltage. Several goodness-of-fit tests are applied to up-and-down test results obtained in the air-insulated rod-plane gap. Three distributions, normal, logistic, and Gumbel, are compared by means of the Kolmogorov--Smirnov goodness-of-fit test, and logistic distribution is also compared to 3-parameter Weibull distributions using the likelihood ratio test. Logistic distribution is found to be a possible alternative to normal and 3-parameter Weibull distributions.
Modeling And Simulation Of Deadbeat-Based Pi Controller In A Single-Phase H-Bridge Inverter For Stand-Alone Applications,
2014
TÜBİTAK
Modeling And Simulation Of Deadbeat-Based Pi Controller In A Single-Phase H-Bridge Inverter For Stand-Alone Applications, Tow Leong Tiang, Dahaman Ishak
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a deadbeat-based proportional-integral (PI) controller for a stand-alone single-phase voltage source inverter using a battery cell as the primary energy source. The inverter system is simulated in MATLAB/Simulink. It consists of a lead acid battery, third-order Butterworth low-pass DC filter and AC filter, H-bridge inverter, step-up transformer, and a variety of loads, as well as its sinusoidal pulse-width modulation (SPWM) deadbeat-based PI controller. In this paper, 2 simulation case studies are carried out, which are the abrupt load changes from a 400 W resistive load to a 500 W resistive load, and from a 400 W resistive …
Hd-Mr: A New Algorithm For Number Recognition In Electrical Meters,
2014
TÜBİTAK
Hd-Mr: A New Algorithm For Number Recognition In Electrical Meters, Miguel Rodriguez, Geovanni Berdugo, Daladier Jabba, Maria Calle, Miguel Jimeno
Turkish Journal of Electrical Engineering and Computer Sciences
Utility companies in developing countries employ analog electrical meters to determine consumption and bill their customers accordingly. Obtaining an accurate reading is an expensive and time-consuming process. High consumption levels of water, energy, or gas are fined by the government; thus, it is necessary to develop tools that allow users to be informed about their consumption in real time. This paper proposes a new number recognition algorithm named the Hausdorff distance for meter reading (HD-MR). Experiments prove that HD-MR can achieve a 99.9% recognition rate, even when recognized numbers are under rotation. The maximum recognition time is 31 ms; hence, …
Rfid And Communication Technologies For An Intelligent Bus Monitoring And Management System,
2014
TÜBİTAK
Rfid And Communication Technologies For An Intelligent Bus Monitoring And Management System, Mahammad Abdul Hannan, Aishah Mustapha, Abdulla Al Mamun, Aini Hussain, Hassan Basri
Turkish Journal of Electrical Engineering and Computer Sciences
This paper highlights the implementation of an intelligent bus monitoring system based on current challenges and problems. In this system, radio frequency identification and integrated sensing technologies, such as a global positioning system, general packet radio service, and geographic information system, are used to monitor the movement of a bus. A new theoretical framework and ruled-based decision algorithms are developed for the system. An experimental setup is developed for the prototype implementation. The results show that the choice of integrated technologies used in the system is suitable to monitor and manage a vehicle transportation system.
A Web Laboratory Using Matlab Builder Ne For Computer Image Processing,
2014
TÜBİTAK
A Web Laboratory Using Matlab Builder Ne For Computer Image Processing, Sezgi̇n Kaçar, Cüneyt Bayilmiş, Özdemi̇r Çeti̇n
Turkish Journal of Electrical Engineering and Computer Sciences
Many various instruments are needed for computer image processing. These instruments are used for image restoration, analysis, etc. This paper presents a novel web laboratory based on MATLAB Builder NE with Web Figure, called ImageWeb, to facilitate computer image processing without needed technical information for users. The developed ImageWeb provides fundamental principles of image processing, including basic, compression, edge detection, filtering, optimization, and histogram processes, and so on. In addition, the usage of MATLAB Builder NE with MATLAB Web Figure provides high flexibility with visualization means such as zoom, rotate, and 3-dimensional view. Users can easily access ImageWeb using only …
Concurrently Attuned Design Of A Wadc-Based Upfc Psdc And Multiinput Pss For Improving Power System Dynamic Performance,
2014
TÜBİTAK
Concurrently Attuned Design Of A Wadc-Based Upfc Psdc And Multiinput Pss For Improving Power System Dynamic Performance, Yashar Hashemi, Rasool Kazemzadeh, Mohammad Reza Azizian, Ahmad Sadeghi Yazdankhah
Turkish Journal of Electrical Engineering and Computer Sciences
A new controller design for a unified power flow controller (UPFC) for damping of power system swings, focusing on interarea modes, is described in this paper. The proposed controller is a dual-layer controller, where the first layer is derived from local signals and the second layer is supplied by global signals, as additional measuring information from suitable remote network locations, where swings are well observable. For damping of low-frequency swing in wide-area operation, since there is little system information in the active power as input of the conventional power system stabilizer (CPSS), the effectiveness of the CPSS is low. For …
Design Of A Double-Stator Linear Switched Reluctance Motor For Shunting Railway Channels,
2014
TÜBİTAK
Design Of A Double-Stator Linear Switched Reluctance Motor For Shunting Railway Channels, El Manaa Barhoumi, Mansour Hajji, Boujemaa Ben Salah
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents the design and modeling of a double-stator linear switched reluctance motor for motorizing a railway channels' shunting system. The magnetic behavior of this actuator is nonlinear due to the saturation and nonlinear magnetization curves of the materials used in this actuator. For this reason, the electromagnetic quantities such as force, flux linkage, and inductance are calculated with the finite element method using the Maxwell tool. The obtained results are presented and discussed. In order to elaborate some control strategies, a new model for the proposed actuator, based on the flux and force characteristics, is validated by the …
Motion Clustering On Video Sequences Using A Competitive Learning Network,
2014
TÜBİTAK
Motion Clustering On Video Sequences Using A Competitive Learning Network, Sali̇h Görgünoğlu, Şafak Altay
Turkish Journal of Electrical Engineering and Computer Sciences
It is necessary to track human movements in crowded places and environments such as stations, subways, metros, and schoolyards, where security is of great importance. As a result, undesired injuries, accidents, and unusual movements can be determined and various precautionary measures can be taken against them. In this study, real-time or existing video sequences are used within the system. These video sequences are obtained from objects such as humans or vehicles, moving actively in various environments. At first, some preprocesses are made respectively, such as converting gray scale, finding the edges of the objects existing in the images, and thresholding …
Early Wakeup: Improving The Drowsy Cache Performance,
2014
TÜBİTAK
Early Wakeup: Improving The Drowsy Cache Performance, Sunghoon Shim, Sungwoo Chung, Hongjun Choi, Cheol Hong Kim
Turkish Journal of Electrical Engineering and Computer Sciences
As process technology scales down, leakage power consumption becomes comparable to dynamic power consumption. The drowsy cache technique is known as one of the most popular techniques for reducing the leakage power consumption in the data cache. However, the drowsy cache is reported to degrade the processor performance significantly. In this paper, to maintain the performance of the processor with the drowsy cache technique, we propose an early wakeup technique, which predicts the next cache line to be requested by utilizing the way-prediction information. The proposed technique efficiently reduces the number of accesses to the cache lines in drowsy mode. …
Design And Implementation Of An Observer Controller For A Buck Converter,
2014
TÜBİTAK
Design And Implementation Of An Observer Controller For A Buck Converter, Shenbaga Lakshmi, Sree Renga Raja
Turkish Journal of Electrical Engineering and Computer Sciences
An observer controller for a buck converter is presented. A state feedback gain matrix is derived in order to achieve the stability of the converter and to ensure the robustness of the controller. A load estimator is designed to estimate the unmeasurable variables and to obtain the zero output voltage error. A pulse-width modulation scheme is adopted to obtain the output voltage regulation. In order to improve the transitory response and dynamic constancy of the converter, the controller parameters are designed based on the current mode control. The design is evaluated and verified using MATLAB/Simulink. An experimental set-up is done …
An Urgent Precaution System To Detect Students At Risk Of Substance Abuse Through Classification Algorithms,
2014
TÜBİTAK
An Urgent Precaution System To Detect Students At Risk Of Substance Abuse Through Classification Algorithms, Faruk Bulut, İhsan Ömür Bucak
Turkish Journal of Electrical Engineering and Computer Sciences
In recent years, the use of addictive drugs and substances has turned out to be a challenging social problem worldwide. The illicit use of these types of drugs and substances appears to be increasing among elementary and high school students. After becoming addicted to drugs, life becomes unbearable and gets even worse for their users. Scientific studies show that it becomes extremely difficult for an individual to break this habit after being a user. Hence, preventing teenagers from addiction becomes an important issue. This study focuses on an urgent precaution system that helps families and educators prevent teenagers from developing …
Retinal Image Analysis Using Multidirectional Functors Based On Geodesic Conversions,
2014
TÜBİTAK
Retinal Image Analysis Using Multidirectional Functors Based On Geodesic Conversions, Saleh Shahbeig
Turkish Journal of Electrical Engineering and Computer Sciences
A retinal image contains vital information. Extracting these features is the first and most important step in the analysis of retinal images for various applications of medical or human recognition. In this study, a morphological-based blood vessel extraction algorithm using adaptive-local analysis from colored retinal images is proposed. In this algorithm, by applying the appropriate morphology functors and local histogram stretching on the retinal images, the brightness of the images is considerably uniformed. Furthermore, curvelet transform (CT) is used to enhance the retinal images by highlighting the edges of the images in various scales and directions and by the adaptive …
Impact Of Plug-In Hybrid Electric Vehicle Charging/Discharging Management On A Microgrid,
2014
TÜBİTAK
Impact Of Plug-In Hybrid Electric Vehicle Charging/Discharging Management On A Microgrid, Kiamars Kaveh, Seyed Mehdi Hakimi, Seyed Masoud Moghaddas-Tafreshi, Fazllolah Naseri
Turkish Journal of Electrical Engineering and Computer Sciences
Plug-in hybrid electric vehicles (PHEVs) may replace conventional vehicles in most urban areas and populated cities due to their lower levels of air pollution compared to internal combustion engine (ICE) vehicles. PHEVs can increase the ability of residential complexes to participate in demand-side management, as well. This paper explores the potential of PHEVs as a flexible load in order to satisfy 2 main issues: increasing the penetration rate of renewable energy in a microgrid and increasing the load factor. In this study, 3 scenarios for managing PHEV charging and discharging are considered. The first scenario connects PHEVs to the grid …
Reliability-Based Generation Resource Planning In Electricity Markets,
2014
TÜBİTAK
Reliability-Based Generation Resource Planning In Electricity Markets, Maziar Mirhoseini Moghaddam, Mohammad Hossein Javidi, Mohsen Parsa Moghaddam, Majid Oloomi Buygi
Turkish Journal of Electrical Engineering and Computer Sciences
This paper proposes a reliability-based competitive generation resource planning model in electricity markets. The Monte Carlo simulation method is applied to consider random outages of generation units and transmission lines as well as load uncertainty. In order to determine the optimal plan for installation of candidate generating units, the decisions of generation companies (GenCos) and the independent system operators (ISOs) are investigated. The method is based on an iterative process for simulating interactivity among ISOs and GenCos and is repeated until security and reliability constraints assumed by the ISO are fulfilled. In the proposed model, the ISO utilizes a new …
A New Edge-Preserving Algorithm Based On The Cie- Lu'v' Color Space For Color Contrast Enhancement,
2014
TÜBİTAK
A New Edge-Preserving Algorithm Based On The Cie- Lu'v' Color Space For Color Contrast Enhancement, Mohammad Zolfaghari, Mehran Yazdi
Turkish Journal of Electrical Engineering and Computer Sciences
Image segmentation and edge detection are the most important presteps in machine vision, and their successfulness can affect the success of the next steps. In this paper, the performance of the Trahanias edge detector in different color spaces, such as RGB, YCbCr, HSI, and CIE Lu'v', is compared in order to find the best color space for image segmentation and edge detection. We then offer an efficient edge-preserving algorithm for color contrast enhancement in the CIE Lu'v' space. The proposed algorithm can increase the color contrast, which causes a remarkable improvement in image segmentation and edge detection in the CIE …
Solving A New Bi-Objective Joint Replenishment Inventory Model With Modified Rand And Genetic Algorithms,
2014
TÜBİTAK
Solving A New Bi-Objective Joint Replenishment Inventory Model With Modified Rand And Genetic Algorithms, Ommolbanin Yousefi, Seyed Jafar Sadjadi
Turkish Journal of Electrical Engineering and Computer Sciences
There are many cases in real inventory systems where more than one objective must be optimized. The main purpose of this research is to develop a multiobjective joint replenishment problem (JRP), where one objective is the minimization of the total inventory investment and another is the minimization of the total inventory ordering and holding costs. To solve the suggested model, 3 algorithms are proposed. In the first algorithm, the existing RAND method, called the best heuristic for solving the JRP, is modified and a new heuristic algorithm is developed to be applicable to the JRP with 2 objectives. The second …
Implementation Of Neural Network-Based Maximum Power Tracking Control For Wind Turbine Generators,
2014
TÜBİTAK
Implementation Of Neural Network-Based Maximum Power Tracking Control For Wind Turbine Generators, Abdulhaki̇m Karakaya, Ercüment Karakaş
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, the maximum power point tracking (MPPT) of a permanent magnet synchronous generator used in a wind generator system is realized by a prototype installed in a laboratory environment. The installed prototype is modeled in a MATLAB/Simulink environment. The MPPT is realized by an artificial neural network (ANN). The obtained simulation and experimental results are compared. The maximum power estimation at various windmill speeds (rpm) of the trained ANN in determined reference speeds is analyzed. The zero crossing points of the phases are determined by a digital signal peripheral interface controller and the system is operated according to …
Model-Free Controller With An Observer Applied In Real-Time To A 3-Dof Helicopter,
2014
TÜBİTAK
Model-Free Controller With An Observer Applied In Real-Time To A 3-Dof Helicopter, Ahsene Boubakir, Salim Labiod, Fares Boudjema, Franck Plestan
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a model-free controller with an observer is presented for a class of uncertain continuous-time multiinput-multioutput nonlinear dynamic systems. The proposed model-free control law consists of 2 parts: the first part is a linear control term used to specify the dynamics of the closed loop system, and the second part is a compensator of the effects of uncertainties and external disturbances. The compensator is synthesized from an estimator of the effects of uncertainties and disturbances based on the Lyapunov approach. In order to estimate the unavailable states of the controlled system, a linear state observer is designed. All …
Design And Implementation Of A Microcontroller Based Wind Energy Conversion System,
2014
TÜBİTAK
Design And Implementation Of A Microcontroller Based Wind Energy Conversion System, Mehmet Demi̇rtaş, Şeri̇f Şerefoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, a dsPIC-controlled DC/DC boost converter and a wind turbine control system that tracks the maximum power point are designed and implemented. In practice, the energy generated by a permanent magnet synchronous wind turbine is applied to the load using a circuit that consists of a rectifier, boost converter, and protective load. The converter operates in the designed mode 35% more efficiently than in the normal operation mode. In addition, the wind turbine is protected from overvoltages in strong windy weather using the protective circuit. Experimental results show that the ripple value on the direct current belonging to …
