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Articles 6151 - 6180 of 10319
Full-Text Articles in Physical Sciences and Mathematics
Privacy Preserving In Association Rules Using A Genetic Algorithm, Rahat Ali Shah, Sohail Asghar
Privacy Preserving In Association Rules Using A Genetic Algorithm, Rahat Ali Shah, Sohail Asghar
Turkish Journal of Electrical Engineering and Computer Sciences
Association rule mining is one of the data mining techniques used to extract hidden knowledge from large datasets. This hidden knowledge contains useful and confidential information that users want to keep private from the public. Similarly, privacy preserving data mining techniques are used to preserve such confidential information or restrictive patterns from unauthorized access. The pattern can be represented in the form of a frequent itemset or association rule. Furthermore, a rule or pattern is marked as sensitive if its disclosure risk is above a given threshold. Numerous techniques have been used to hide sensitive association rules by performing some …
A New Method For Extraction Of Speech Features Using Spectral Delta Characteristics And Invariant Integration, Hassan Farsi, Samana Kuhimoghadam
A New Method For Extraction Of Speech Features Using Spectral Delta Characteristics And Invariant Integration, Hassan Farsi, Samana Kuhimoghadam
Turkish Journal of Electrical Engineering and Computer Sciences
We propose a new feature extraction algorithm that is robust against noise. Nonlinear filtering and temporal masking are used for the proposed algorithm. Since the current automatic speech recognition systems use invariant-integration and delta-delta techniques for speech feature extraction, the proposed algorithm improves speech recognition accuracy appropriately using a delta-spectral feature instead of invariant integration. One of the nonenvironmental factors that reduce recognition accuracy is the vocal tract length (VTL), leading to a mismatch between the training and testing data. We can use the invariant-integration feature idea for decreasing the VTL effects. The aim of this paper is to provide …
Feature Selection On Single-Lead Ecg For Obstructive Sleep Apnea Diagnosis, Hüseyi̇n Gürüler, Mesut Şahi̇n, Abdullah Feri̇koğlu
Feature Selection On Single-Lead Ecg For Obstructive Sleep Apnea Diagnosis, Hüseyi̇n Gürüler, Mesut Şahi̇n, Abdullah Feri̇koğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Many articles that appeared in the literature agreed upon the feasibility of diagnosing obstructive sleep apnea (OSA) with a single-lead electrocardiogram. Although high accuracies have been achieved in detection of apneic episodes and classification into apnea/hypopnea, there has not been a consensus on the best method of selecting the feature parameters. This study presents a classification scheme for OSA using common features belonging to the time domain, frequency domain, and nonlinear calculations of heart rate variability analysis, and then proposes a method of feature selection based on correlation matrices (CMs). The results show that the CMs can be utilized in …
Competitive Unit Maintenance Scheduling In A Deregulated Environment Based On Preventing Market Power, Hessam Golmohamadi, Maryam Ramezani, Hamid Falaghi
Competitive Unit Maintenance Scheduling In A Deregulated Environment Based On Preventing Market Power, Hessam Golmohamadi, Maryam Ramezani, Hamid Falaghi
Turkish Journal of Electrical Engineering and Computer Sciences
With the advent of electricity markets, the traditional approach to unit maintenance scheduling (UMS) needs to undergo major changes in order to be compatible with competitive environment structures. The transition from a vertical power system to a competitive structure makes many challenges for policymakers and market designers. In this paper, a new approach to UMS in competitive electricity markets is presented. The main part of this study involves both how to treat generating companies (GENCOs) fairly and how to guarantee power system security during the maintenance scheduling. This paper advances the UMS in the electricity market so that one can …
Continuity Of Currents Across Neighboring Cells In Pmm Analysis Of Thin-Wire Grids, Sena Esen Bayer Keski̇n, Ahmet Ari̇f Ergi̇n
Continuity Of Currents Across Neighboring Cells In Pmm Analysis Of Thin-Wire Grids, Sena Esen Bayer Keski̇n, Ahmet Ari̇f Ergi̇n
Turkish Journal of Electrical Engineering and Computer Sciences
This article presents a new approach for the analysis of electromagnetic scattering from a rectangular wire mesh. In this sense, a basis function that considers the flow of a current from one cell to the next is proposed in light of Floquet's theorem. The proposed basis function enables the use of periodic method of moments in frequency-selective surfaces composed of thin wires in the case of a system having a connection with neighboring cells, such as thin-wire grids. The validity of the proposed solution approach is tested in 2 distinct cases (with and without a neighbor connection) for scattered fields. …
Multiple-Global-Best Guided Artificial Bee Colony Algorithm For Induction Motor Parameter Estimation, Abdul Ghani Abro, Junita Mohamad Saleh
Multiple-Global-Best Guided Artificial Bee Colony Algorithm For Induction Motor Parameter Estimation, Abdul Ghani Abro, Junita Mohamad Saleh
Turkish Journal of Electrical Engineering and Computer Sciences
An induction motor is the most commonly used motor in industry today. Motor circuit parameters are essential for designing, evaluating performance, and controlling the applications of the motor. However, it is difficult to measure the electric parameters, e.g., resistance and reactance, of induction motors accurately. Therefore, researchers have noted the parameter estimation of induction motors as an essential optimization problem. The artificial bee colony (ABC) algorithm is an efficient element of bioinspired optimization algorithms and has been successfully applied in numerous engineering applications. However, the ABC algorithm suffers from slow convergence and poor exploitation. Additionally, there are bleak chances of …
Robust Stability Of Linear Uncertain Discrete-Time Systems With Interval Time-Varying Delay, Mehmet Nur Alpaslan Parlakçi
Robust Stability Of Linear Uncertain Discrete-Time Systems With Interval Time-Varying Delay, Mehmet Nur Alpaslan Parlakçi
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a robust stability problem for linear uncertain discrete-time systems with interval time-varying delay and norm-bounded uncertainties. First, a necessary and sufficient stability condition is obtained by employing a well-known lifting method and switched system approach for nominal discrete-time delay systems. Both the stability method of checking the characteristic values inside the unit circle and a Lyapunov function-based stability result are taken into consideration. Second, a simple Lyapunov--Krasovskii functional (LKF) is selected, and utilizing a generalized Jensen sum inequality, a sufficient stability condition is presented in the form of linear matrix inequalities. Third, a novel LKF is proposed …
Perceptual Quality Evaluation Of Asymmetric Stereo Video Coding For Efficient 3d Rate Scaling, Nükhet Özbek, Gi̇zem Ertan, Oktay Karakuş
Perceptual Quality Evaluation Of Asymmetric Stereo Video Coding For Efficient 3d Rate Scaling, Nükhet Özbek, Gi̇zem Ertan, Oktay Karakuş
Turkish Journal of Electrical Engineering and Computer Sciences
In 3D perception, the binocular suppression of the human vision, perceiving high quality 3D video in the case of a view in higher quality, can be exploited in asymmetric stereo video coding for efficient 3D rate scaling. Hence, the best stereo rate-visual distortion performance may be gained by asymmetric coding, which is the reduction of the spatial and/or quantization resolution of the low-quality view, while keeping the high-quality view in full resolution. However, how to determine the level of asymmetry and what type of scaling should be chosen are still in question. In this work, we try to assess the …
Wireless Sensor Localization Using Enhanced Dv-Aoa Algorithm, Peter Brida, Juraj Machaj, Jozef Benikovsky
Wireless Sensor Localization Using Enhanced Dv-Aoa Algorithm, Peter Brida, Juraj Machaj, Jozef Benikovsky
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we deal with the improvement of the positioning accuracy of distance vector (DV)-based positioning algorithms, which use angular information DV- angle of arrival (AoA). This algorithm belongs to an ad-hoc positioning system. We focus on the improvement of the algorithm and its enhanced version is presented. The angular information of particular nodes is obtained and processed by the original algorithm; however, the final position estimation is determined by the proposed novel algorithm using only a subset of all intersections. We assign weights to the individual intersections according to their positions and the positions of the RNs. For …
Impact Of Small-World Topology On The Performance Of A Feed-Forward Artificial Neural Network Based On 2 Different Real-Life Problems, Okan Erkaymaz, Mahmut Özer, Nejat Yumuşak
Impact Of Small-World Topology On The Performance Of A Feed-Forward Artificial Neural Network Based On 2 Different Real-Life Problems, Okan Erkaymaz, Mahmut Özer, Nejat Yumuşak
Turkish Journal of Electrical Engineering and Computer Sciences
Since feed-forward artificial neural networks (FFANNs) are the most widely used models to solve real-life problems, many studies have focused on improving their learning performances by changing the network architecture and learning algorithms. On the other hand, recently, small-world network topology has been shown to meet the characteristics of real-life problems. Therefore, in this study, instead of focusing on the performance of the conventional FFANNs, we investigated how real-life problems can be solved by a FFANN with small-world topology. Therefore, we considered 2 real-life problems: estimating the thermal performance of solar air collectors and predicting the modulus of rupture values …
Source Microphone Identification From Speech Recordings Based On A Gaussian Mixture Model, Ömer Eski̇dere
Source Microphone Identification From Speech Recordings Based On A Gaussian Mixture Model, Ömer Eski̇dere
Turkish Journal of Electrical Engineering and Computer Sciences
Microphone identification is a specific type of media forensics that investigates whether it is possible to identify the source microphone from speech recordings. The main aim of this study is to find out which of the several feature extraction techniques are best suited to the source microphone identification systems. We perform microphone identification experiments with 16 different microphones using 3 datasets. In order to improve the results on the datasets, we also investigate the important parameters that may affect the microphone identification performance. Our experimental results show that the proposed method is comparable to the existing studies in a closed-set …
Recurrent Wavelet Neural Network Control Of A Pmsg System Based On A Pmsm Wind Turbine Emulator, Chih Hong Lin
Recurrent Wavelet Neural Network Control Of A Pmsg System Based On A Pmsm Wind Turbine Emulator, Chih Hong Lin
Turkish Journal of Electrical Engineering and Computer Sciences
A recurrent wavelet neural network (NN)-controlled 3-phase permanent magnet synchronous generator system (PMSG), which is direct-driven by a permanent magnet synchronous motor (PMSM) based on a wind turbine emulator, is proposed to control the output values of a rectifier (or AC to DC power converter) and inverter (or DC to AC power converter) in this study. First, a closed-loop PMSM drive control based on a wind turbine emulator is designed to generate the maximum power for the PM synchronous generator (PMSG) system according to different wind speeds. Next, the rotor speed of the PMSG, the DC bus voltage, and the …
Impact Of Plug-In Hybrid Electric Vehicle Charging/Discharging Management On A Microgrid, Kiamars Kaveh, Seyed Mehdi Hakimi, Seyed Masoud Moghaddas-Tafreshi, Fazllolah Naseri
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 …
Shuffled Frog Leaping Algorithm Optimization For Ac--Dc Optimal Power Flow Dispatch, Abolfazl Rahiminejad, Arash Alimardani, Behrooz Vahidi, Seyed Hossein Hosseinian
Shuffled Frog Leaping Algorithm Optimization For Ac--Dc Optimal Power Flow Dispatch, Abolfazl Rahiminejad, Arash Alimardani, Behrooz Vahidi, Seyed Hossein Hosseinian
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a simple-implemented and reliable AC--DC optimal power flow (OPF) is proposed. Although high-voltage direct current (HVDC) transmission lines are being increasingly used in power systems, new optimization algorithms such as evolutionary and memetic algorithms, which never stick in local minimum, so far have not been implemented in the AC--DC OPF problem. An evolutionary algorithm known as the shuffled frog leaping algorithm (SFLA) is proposed in this paper to solve the OPF dispatch in an AC--DC power system (including both high-voltage alternating current and HVDC transmission lines). The implementation of the AC--DC OPF with these kinds of methods …
Reliability-Based Generation Resource Planning In Electricity Markets, Maziar Mirhoseini Moghaddam, Mohammad Hossein Javidi, Mohsen Parsa Moghaddam, Majid Oloomi Buygi
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 …
Model-Based Robust Chaotification Using Sliding Mode Control, Aykut Kocaoğlu, Cüneyt Güzeli̇ş
Model-Based Robust Chaotification Using Sliding Mode Control, Aykut Kocaoğlu, Cüneyt Güzeli̇ş
Turkish Journal of Electrical Engineering and Computer Sciences
Chaos is a complex behavior of dynamical nonlinear systems that is undesirable in most applications and should be controlled; however, it is desirable in some situations and should be generated. In this paper, a robust chaotification scheme based on sliding mode control is proposed for model based chaotification. A continuous time single input observable system is considered such that it is subject to parameter uncertainties, nonlinearities, noises, and disturbances, which are all additive to the input and can be modeled as an unknown function but bounded by a known function. The designed dynamical state feedback control law forces the system …
A New Edge-Preserving Algorithm Based On The Cie- Lu'v' Color Space For Color Contrast Enhancement, Mohammad Zolfaghari, Mehran Yazdi
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 …
A Low-Order Nonlinear Amplifier Model With Distributed Delay Terms, Ahmet Hayretti̇n Yüzer, Şi̇mşek Demi̇r
A Low-Order Nonlinear Amplifier Model With Distributed Delay Terms, Ahmet Hayretti̇n Yüzer, Şi̇mşek Demi̇r
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a novel behavioral modeling technique for the characterization of memory effects of amplifiers is proposed. This characterization utilizes asymmetric intermodulation distortion (IMD) components, which are the result of a 2-tone excitation of a nonlinear amplifier. These asymmetric IMD components are represented basically by a power series, where each term in the series has its own time delay term. These time delay terms successfully justify the presence of asymmetry in the intermodulation components, which leads to the prediction of amplitude-to-amplitude and amplitude-to-phase distortions. The parameters of the model are extracted using 2-tone measurements. A 100-W peak power amplifier …
New Throughput-Based Antenna Selection Scheme, Mohammad Lari, Abbas Mohammadi, Abdolali Abdipour
New Throughput-Based Antenna Selection Scheme, Mohammad Lari, Abbas Mohammadi, Abdolali Abdipour
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a new throughput-based transmit antenna selection (AS) scheme is evaluated. First, a closed-form solution for the throughput rate of a multiple-input multiple-output (MIMO) system, with a truncated selective repeat automatic repeat request (TSR-ARQ) or selective repeat plus go-back-N automatic repeat request (SR+GBN-ARQ) protocol at the data link layer, is proposed. In addition, a throughput-based AS technique with adaptive modulation is also investigated. For this purpose, the throughput and packet error rates of a MIMO system with a transmit AS and TSR-ARQ protocol at the data link layer are analyzed. This study is conducted in 2 different cases. …
Comparison Of Different Methods For Determining Diabetes, Mehmet Recep Bozkurt, Ni̇lüfer Yurtay, Zi̇ynet Yilmaz, Cengi̇z Sertkaya
Comparison Of Different Methods For Determining Diabetes, Mehmet Recep Bozkurt, Ni̇lüfer Yurtay, Zi̇ynet Yilmaz, Cengi̇z Sertkaya
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, the Pima Indian Diabetes dataset was categorized with 8 different classifiers. The data were taken from the University of California Irvine Machine Learning Repository's web site. As a classifier, 6 different neural networks [probabilistic neural network (PNN), learning vector quantization, feedforward networks, cascade-forward networks, distributed time delay networks (DTDN), and time delay networks], the artificial immune system, and the Gini algorithm from decision trees were used. The classifier's performance ratios were studied separately as accuracy, sensitivity, and specificity and the success rates of all of the classifiers are presented. Among these 8 classifiers, the best accuracy and …
A Novel Hybrid Recurrent Wavelet Neural Network Control Of Permanent Magnet Synchronous Motor Drive For Electric Scooter, Chih Hong Lin
A Novel Hybrid Recurrent Wavelet Neural Network Control Of Permanent Magnet Synchronous Motor Drive For Electric Scooter, Chih Hong Lin
Turkish Journal of Electrical Engineering and Computer Sciences
Due to the electric scooter with nonlinear uncertainties, e.g., nonlinear friction force of the transmission belt, the linear controller was made to disable speed tracking control. In order to overcome this problem, a novel hybrid recurrent wavelet neural network (NHRWNN) control system is proposed to control for a permanent-magnet synchronous motor-driven electric scooter in this study. The NHRWNN control system consists of a supervised control, a recurrent wavelet neural network (RWNN), and a compensated control with adaptive law. According to the Lyapunov stability theorem and the gradient descent method, the on-line parameter training methodology of the RWNN can be derived …
An Artificial Neural Network Approach For Sensorless Speed Estimation Via Rotor Slot Harmonics, Hayri̇ Arabaci
An Artificial Neural Network Approach For Sensorless Speed Estimation Via Rotor Slot Harmonics, Hayri̇ Arabaci
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a sensorless speed estimation method with an artificial neural network for squirrel cage induction motors is presented. Motor current is generally used for sensorless speed estimation. Rotor slot harmonics are available in the frequency spectrum of the current. The frequency components of these determined harmonics are used to estimate the speed of the motor in which the number of rotor slots is given. In the literature, individual algorithms have been used to calculate the speed from the slot harmonics. Unlike the literature, in the proposed method, an artificial neural network is used to extract the speed from …
A Control Scheme Employing An Adaptive Hysteresis Current Controller And An Uncomplicated Reference Current Generator For A Single-Phase Shunt Active Power Filter, Hüseyi̇n Doğan, Ramazan Akkaya
A Control Scheme Employing An Adaptive Hysteresis Current Controller And An Uncomplicated Reference Current Generator For A Single-Phase Shunt Active Power Filter, Hüseyi̇n Doğan, Ramazan Akkaya
Turkish Journal of Electrical Engineering and Computer Sciences
In recent years, active power filters (APFs) have become popular because of their excellent current harmonics and reactive power mitigation ability. The performance of the APF is directly related to the selected control strategy, which is mainly divided into 2, the reference current generation and current control. Most of the reference current generation methods are very complicated and require precise mathematical expressions. Moreover, being the most preferred current control method, conventional hysteresis controllers have a fixed bandwidth, which causes different total demand distortion values under different load conditions. In this study, a novel control scheme for a single-phase shunt APF …
Induction Motor Parameter Estimation Using Metaheuristic Methods, Ali̇ İhsan Çanakoğlu, Asim Gökhan Yetgi̇n, Hasan Temurtaş, Mustafa Turan
Induction Motor Parameter Estimation Using Metaheuristic Methods, Ali̇ İhsan Çanakoğlu, Asim Gökhan Yetgi̇n, Hasan Temurtaş, Mustafa Turan
Turkish Journal of Electrical Engineering and Computer Sciences
The steady-state equivalent circuit parameters of an induction motor can be estimated using the operation characteristics that are provided by manufacturers. The characteristics of the motor used in estimation methods are the starting, maximum, and nominal torque values; the power factor; and efficiency. The operation characteristics of a motor given in data sheets are generally based on design parameters and are not suitable with real values. For this reason, in this paper, the data used in the parameter estimation for induction motors are taken from the literature. Using an optimization method for parameter estimation is useful for comparing the manufacturer …
Digital Control System Design And Analyses Of A 3-Phase Bearingless Induction Motor, Wenshao Bu, Conglin Zu, Shaojie Wang, Shenghua Huang
Digital Control System Design And Analyses Of A 3-Phase Bearingless Induction Motor, Wenshao Bu, Conglin Zu, Shaojie Wang, Shenghua Huang
Turkish Journal of Electrical Engineering and Computer Sciences
The overall configuration of a magnetic suspension decoupling control system is designed to realize the reliable digital control of a 3-phase bearingless induction motor whose rotor windings are not pole-specific. Based on a digital signal processor complementary metal-oxide semiconductor chip, the digital control hardware and software systems are analyzed and designed. In this paper, the calculation and regulation of the motor rotational speed, correction and regulation methods of the radial displacements, calculation and compensation algorithms of the unilateral magnetic pulls, induction compensation algorithm of the effective suspension control current, current regulation, and space-vector pulse width modulation algorithms, are presented in …
Class-E Gaas Hbt Power Amplifier With Passive Linearization Scheme For Mobile Wireless Communications, Uthirajoo Eswaran, Harikrishnan Ramiah, Jeevan Kanesan, Ahmed Wasif Reza
Class-E Gaas Hbt Power Amplifier With Passive Linearization Scheme For Mobile Wireless Communications, Uthirajoo Eswaran, Harikrishnan Ramiah, Jeevan Kanesan, Ahmed Wasif Reza
Turkish Journal of Electrical Engineering and Computer Sciences
A linearization technique for improving the class-E power amplifier (PA)'s adjacent channel power ratio (ACPR) is proposed. The design is simulated in a 2-mu m InGaP/GaAs heterojunction bipolar transistor process. The integration of a passive predistorter at the input of the PA linearizes the proposed architecture. At a 29-dBm output power, the PA's ACPR is indicated to be -51 dBc, meeting the stringent code division multiple access regulation. At this exact output power, the simulated power added efficiency is 55 % with the collector voltage headroom consumption of 3.4 V. The input return loss, S11, of the PA is simulated …
A Reconfigurable Baseband Circuit Applied For Wimax Low-If Receivers, Xin Cheng, Guangjun Xie
A Reconfigurable Baseband Circuit Applied For Wimax Low-If Receivers, Xin Cheng, Guangjun Xie
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a reconfigurable baseband circuit for WiMAX low-IF receivers, including a complex filter and 2 automatic gain controllers (AGCs) for I and Q channels. Only by changing the capacitor values can the center and cutoff frequencies of the complex filter be adjusted simultaneously to realize the reconfigurability. Meanwhile, a novel one-step method to obtain fast gain settling of AGCs is proposed. The chip is fabricated in 0.13-\mu m CMOS technology, occupies 0.9 \times 1.3 mm^2, and consumes 14.8 mW of power with a 1.2-V power supply. The measurement results show a reconfigurable bandwidth of 2 K to 3.5/5/10 …
Sliding Mode Controller Design With Fractional Order Differentiation: Applications For Unstable Time Delay Systems, Celaleddi̇n Yeroğlu, Gürkan Kavuran
Sliding Mode Controller Design With Fractional Order Differentiation: Applications For Unstable Time Delay Systems, Celaleddi̇n Yeroğlu, Gürkan Kavuran
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a design method for a sliding mode controller with the contribution of a fractional order differential operator. The conventional sliding mode controller has been widely studied in different control applications. This paper proposes that the fractional order differential operator enlarges the output span of the classical sliding mode controller to obtain a better-fitting control signal for enhanced control performance. The sliding surface and the equivalent control law are modified with the addition of a fractional differential operator and a conventional one. The proposed sliding mode controller with fractional order differentiation is applied to the unstable time delay …
Abrupt And Incipient Fault Detection And Compensation For A 4-Tank System Benchmark, Pedram Hajiani, Javad Poshtan
Abrupt And Incipient Fault Detection And Compensation For A 4-Tank System Benchmark, Pedram Hajiani, Javad Poshtan
Turkish Journal of Electrical Engineering and Computer Sciences
Fault detection and compensation play a key role in enhancing the high demand for performance and security in technological systems. This paper proposes an active fault-tolerant control scheme that detects and compensates for actuator faults in a 4-tank system benchmark. The faults are modeled as a drastic gain loss in actuators (pumps), which could lead to a large loss in the nominal performance. The model-based approach uses a recursive least squares parameter estimation algorithm to form a fault detection and diagnosis subsystem and utilizes a parametric eigenstructure assignment method to reconfigure the state feedback controller. The designed controller is simulated …
Horizontal Dilution Of Precision-Based Ultra-Wideband Positioning Technique For Indoor Environments, Kerem Küçük
Horizontal Dilution Of Precision-Based Ultra-Wideband Positioning Technique For Indoor Environments, Kerem Küçük
Turkish Journal of Electrical Engineering and Computer Sciences
Ultra-wideband (UWB) technology provides considerable performance in many indoor localization problems thanks to its very wide spectrum and high-resolution characteristics. In this paper, we propose using the horizontal dilution of precision (HDOP) to decrease the localization error in indoor environments for UWB localization systems. To achieve this aim, first we determine the positioning accuracy of a commercially available UWB positioning system using laboratory experiments. Next, the results of the position estimations obtained by the HDOP are compared with the experimental results acquired by the UWB positioning system. Finally, we investigate a detailed comparison with the least squares (LS), nonlinear regression …