A Novel Ddcc+ Based First-Order Current-Mode Active-C All-Pass Filter Using A Grounded Capacitor,
2017
TÜBİTAK
A Novel Ddcc+ Based First-Order Current-Mode Active-C All-Pass Filter Using A Grounded Capacitor, Remzi̇ Arslanalp
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, a novel first-order current-mode active-C all-pass filter based on a companding idea is proposed. In the design of the filter, a state space method is used. The proposed structure consists of only two plus-type differential difference current conveyors, nine external MOSFETs, and a single grounded capacitor. The dominant advantages of the proposed filter are briefly described as follows: offering resistorless design, consuming low power, having an electronic tunability property of its pole frequency, and not suffering from the disadvantage of any passive component matching conditions. By cascading two all-pass filters in a closed negative feedback loop, a …
A Novel Approach For Extracting Ideal Exemplars By Clustering For Massivetime-Ordered Datasets,
2017
TÜBİTAK
A Novel Approach For Extracting Ideal Exemplars By Clustering For Massivetime-Ordered Datasets, Ömer Faruk Ertuğrul
Turkish Journal of Electrical Engineering and Computer Sciences
The number and length of massive datasets have increased day by day and this yields more complex machine learning stages due to the high computational costs. To decrease the computational cost many methods were proposed in the literature such as data condensing, feature selection, and filtering. Although clustering methods are generally employed to divide samples into groups, another way of data condensing is by determining ideal exemplars (or prototypes), which can be used instead of the whole dataset. In this study, first the efficiency of traditional data condensing by clustering approach was confirmed according to obtained accuracies and condensing ratios …
Nonlinear Model Predictive Control Based On Fuzzy Wavelet Neural Network And Chaos Optimization,
2017
TÜBİTAK
Nonlinear Model Predictive Control Based On Fuzzy Wavelet Neural Network And Chaos Optimization, Mehrnoush Davanipour, Hanieh Asadipooya
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper a combined controller is proposed for nonlinear dynamical systems. The controller is constructed by a fuzzy wavelet network and nonlinear model predictive control. Chaotic optimization, which is fast and robust, is applied to generate optimized controlled input in nonlinear model predictive control. The ability of the fuzzy wavelet neural network and the proposed controller is shown by simulation. It is illustrated that the proposed method is able to increase the speed of tracking in addition to having very little steady state error. Using chaotic optimization makes the controller robust in the presence of noise.
A Reduced-Order Observer Based On Stator Flux Estimation With Straightforward Parameter Identification For Sensorless Control Of Dfigs, Rahim Ajabi Farshbaf, Mohammad Reza Azizian, Vahid Eslampanah
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a new reducer-order observer for sensorless control of doubly fed induction generators (DFIGs), based on the Luenberger algorithm. Stable operation of the suggested observer is also considered in the design guidelines. Stator flux is selected as the state variable for the observer and its estimation error is used to correct the observer operation. The gain matrix of the proposed observer is calculated on the basis of flux error dynamics. The adaptation mechanism of the proposed observer is selected based on an estimation of rotor currents. A proportional integrator (PI) block is used in the structure of the …
Robust Control For Line-Of-Sight Stabilization Of A Two-Axis Gimbal System,
2017
TÜBİTAK
Robust Control For Line-Of-Sight Stabilization Of A Two-Axis Gimbal System, Mehmet Baskin, Mehmet Kemal Leblebi̇ci̇oğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Line-of-sight stabilization against various disturbances is an essential property of gimbaled imaging systems mounted on mobile platforms. In recent years, the importance of target detection from higher distances has increased. This has raised the need for better stabilization performance. For that reason, stabilization loops are designed such that they have higher gains and larger bandwidths. As these are required for good disturbance attenuation, sufficient loop stability is also needed. However, model uncertainties around structural resonances impose strict restrictions on sufficient loop stability. Therefore, to satisfy high stabilization performance in the presence of model uncertainties, robust control methods are required. In …
A Hardware One-Time Pad Prototype Generator For Localising Cloud Security,
2017
Technological University Dublin
A Hardware One-Time Pad Prototype Generator For Localising Cloud Security, Jonathan Blackledge, Paul Tobin, Lee Tobin, Mick Mckeever
Conference papers
Abstract: In this paper, we examine a system for encrypting data before storing in the Cloud. Adopting this system gives excellent security to stored data and complete control for accessing data by the client at different locations. The motivation for developing this personal encryption came about because of poor Cloud security and doubts over the safety of public encryption algorithms which might contain backdoors. However, side-channel attacks and other unwanted third-party interventions in Cloud security, probably contribute more to the poor security record history. These factors led to the development of a prototype for personalising security locally which defeats cryptanalysis. …
Application Of Artificial Intelligence For Detecting Computing Derived Viruses,
2017
Technological University Dublin
Application Of Artificial Intelligence For Detecting Computing Derived Viruses, Jonathan Blackledge, Omotayo Asiru, Moses Dlamini
Conference papers
Computer viruses have become complex and operates in a stealth mode to avoid detection. New viruses are argued to be created each and every day. However, most of these supposedly ‘new’ viruses are not completely new. Most of the supposedly ‘new’ viruses are not necessarily created from scratch with completely new (something novel that has never been seen before) mechanisms. For example, most of these viruses just change their form and signatures to avoid detection. But their operation and the way they infect files and systems is still the same. Hence, such viruses cannot be argued to be new. In …
A Mobile Platform Using Software Defined Radios For Wireless Communication Systems Experimentation,
2017
Old Dominion University
A Mobile Platform Using Software Defined Radios For Wireless Communication Systems Experimentation, Otilia Popescu, Shiny Abraham, Samy El-Tawab
Engineering Technology Faculty Publications
A distinctive feature of wireless communication systems is implied by the fact that there is no physical connection between the transmitter and its corresponding receiver, which enables user mobility. However, experimenting with wireless communication systems is mostly done in the lab, where transmitters and receivers are setup on benches, in stationary settings. This prevents students from experiencing fading and other propagation effects associated with mobile wireless channels. This paper describes a mobile platform for wireless communication experimentation that enables students to run experiments beyond the confines of a traditional lab, in realistic settings that cover indoor and outdoor scenarios with …
Calculation Of Creepage Discharge Safety Factors Against The Tangential Component Of Electric Fields In The Insulation Structure Of Power Transformers, Arsalan Hekmati
Turkish Journal of Electrical Engineering and Computer Sciences
Creepage discharges are a main cause of insulation damage in power transformers during repeated tests or during operation. In this paper, a hazardous region in the insulation structure of power transformers (the interface between solid and liquid insulation at the top edge of a high-voltage electrode) is considered, and the impact of a very important factor of the surface discharge initiation and propagation (the tangential component of the electric field) on the strength of the insulation structure is investigated in power transformers. Insulation system reliability against this tangential component is presented as a safety factor. Two methods based on cumulative …
Numerical Study Of Ac Loss Of Two-Layer Hts Power Transmission Cables Composed Of Coated Conductors With A Ferromagnetic Substrate, Şükrü Yildiz, Fedai̇ İnanir, Ahmet Çi̇çek, Fedor Gömöry
Turkish Journal of Electrical Engineering and Computer Sciences
This work includes the simulation of hysteretic AC losses in two-layer HTS power transmission cables made of second-generation high-temperature superconducting tapes with a ferromagnetic substrate subject to an oscillating AC transport current, calling upon the COMSOL Multiphysics finite-element software program and exploiting an AC/DC module. How the AC transport loss is influenced by the arrangement of tapes, as well as the optimized design of superconducting power cables based on YBCO-coated conductors, are investigated. According to the radial arrangement of the tapes, four different orientations of ferromagnetic substrate are considered: 1) out-in (substrate of inner/outer layer facing outward/inward), 2) in-out (substrate …
Lossless Predictive Coding Of Electric Signal Waveforms,
2017
TÜBİTAK
Lossless Predictive Coding Of Electric Signal Waveforms, Krzysztof Duda
Turkish Journal of Electrical Engineering and Computer Sciences
This paper describes a new predictive coding algorithm designed for lossless compression of electric signal waveforms. Prediction coefficients are obtained from the sinusoidal signal autoregressive model. Predictors for a single sinusoid and the sum of two and three sinusoids are considered. Integer-to-integer coding is obtained by the proper (i.e. reversible) quantization of computations. The proposed coding algorithm shows better performance than the commonly used 2nd order differences coding and linear prediction coding that is optimal in the least squares sense.
Heuristic Algorithm-Based Estimation Of Rotor Resistance Of An Induction Machine By Slot Parameters With Experimental Verification, Mehmet Çelebi̇, Murat Tören
Turkish Journal of Electrical Engineering and Computer Sciences
The estimations of induction machine equivalent circuit parameters are still being widely used in the analysis and in determining the characteristics of the machine. Since the most important part of the machine is the rotor where torque is produced, the calculation of rotor resistance correctly will directly affect all other data. Almost all parameters belonging to the stator side can easily be determined through external measurements. However, due to the formulation of the rotor as a closed box, estimating rotor resistance and the rotor's slot shape by heuristic algorithms, without damaging the rotor physically, and comparing it with its actual …
A Linear Magnetorheological Brake With Multipole Outer Coil Structure For High On-State And Low Off-State Force Outputs,
2017
TÜBİTAK
A Linear Magnetorheological Brake With Multipole Outer Coil Structure For High On-State And Low Off-State Force Outputs, Özgür Başer, Mehmet Alper Demi̇ray, Aytuğ Baş, Ergi̇n Kiliç, Gali̇p Ozan Erol
Turkish Journal of Electrical Engineering and Computer Sciences
A wide range of braking forces, from near zero to high values, is required in specific applications such as forces in haptic devices or steering stability in motorcycles. Classical piston cylinder type magnetorheological (MR) brakes are not suitable for these applications due to their high off-state forces. In this paper, a new linear type MR brake employing shear mode braking principle with a multipole outer coil structure is presented for high on-state and low off-state force outputs. To implement this device, an analytical model of the brake is derived by using magnetic circuit analysis to determine braking force. Magnetic finite …
Performance Comparison Of The Notable Acceleration- And Angle-Based Guidance Laws For A Short-Range Air-To-Surface Missile,
2017
TÜBİTAK
Performance Comparison Of The Notable Acceleration- And Angle-Based Guidance Laws For A Short-Range Air-To-Surface Missile, Bülent Özkan, Mustafa Kemal Özgören, Gökmen Mahmutyazicioğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Short-range air-to-surface missiles have become globally popular in the last two decades. As a performance driver, the type of guidance law gains importance. In this study, proportional navigation, velocity pursuit, and augmented proportional navigation guidance laws, whose resulting guidance commands take the form of lateral acceleration, are applied to a short-range air-to-surface missile against both stationary and maneuvering ground targets. Body pursuit and linear homing guidance laws, which yield angular commands, are additionally applied. Having completed the relevant computer simulations, we conclude that none of the acceleration- and angle-based guidance laws are absolutely superior to the others.
Robust H$\Infty $ Control For Chaotic Supply Chain Networks,
2017
TÜBİTAK
Robust H$\Infty $ Control For Chaotic Supply Chain Networks, Hamid Norouzi Nav, Mohammad Reza Jahedmotlagh, Ahmad Makui
Turkish Journal of Electrical Engineering and Computer Sciences
A supply chain network (SCN) is a complex nonlinear system involving multiple entities. The policy of each entity in decision-making and the uncertainties of demand and supply (or production) significantly affect the complexity of its behavior. Although several studies have presented information about the measurement of chaos in the supply chain, there has not been an appropriate way to control the chaos in it. In this paper, the chaos control problem is considered for a SCN with a time-varying delay between its entities. The innovation of this paper is the more comprehensive modeling, analysis, and control of chaotic behavior in …
A New And Secure Digital Image Scrambling Algorithm Based On 2d Cellular Automata,
2017
TÜBİTAK
A New And Secure Digital Image Scrambling Algorithm Based On 2d Cellular Automata, Gi̇zem Dursun, Fadi̇me Özer, Ufuk Özkaya
Turkish Journal of Electrical Engineering and Computer Sciences
In this work, a new and secure digital image scrambling algorithm for grayscale images is presented. The main goal of this algorithm is to change and reorder the positions of the pixel values of the grayscale images according to the rules of Conway's Game of Life. For this purpose, an image scrambling matrix is proposed. The proposed algorithm is mostly applied to known benchmark images of various sizes and histograms. Moreover, the proposed algorithm is applied to noisy and low-contrast images to evaluate the performance of the algorithm in consumer applications. The scrambling performance of the algorithm is examined through …
A Meander Coupled Line Wideband Power Divider With Open Stubs And Dgs For Mobile Application,
2017
TÜBİTAK
A Meander Coupled Line Wideband Power Divider With Open Stubs And Dgs For Mobile Application, Sivaprakash Somalinga Chandrasekarani, Sivanantharaja Raja Avaninathan, Pavithra Murugesan
Turkish Journal of Electrical Engineering and Computer Sciences
A novel meander coupled line power divider for wide band operation from 0.5 GHz to 2.5 GHz with reduced size for mobile application is proposed in this paper. The wide band operation of the coupled line power divider is obtained using open stubs and defected ground structures. The folding of the coupled line reduces the size of the power divider. The proposed power divider has 65% of size reduction in comparison with the existing power divider. All the S-parameters such as return loss, insertion loss, and isolation at different ports are simulated and measured. Bandwidth of 2 GHz is obtained. …
Adaptive Joint Block-Weighted Collaborative Representation For Facial Expression Recognition,
2017
TÜBİTAK
Adaptive Joint Block-Weighted Collaborative Representation For Facial Expression Recognition, Zhe Sun, Zhengping Hu, Meng Wang, Shuhuan Zhao
Turkish Journal of Electrical Engineering and Computer Sciences
Facial expression recognition (FER) plays a significant role in human-computer interactions. Recently, regularized linear representation-based classification has achieved satisfying results in FER. Considering that different blocks in a sample should contribute differently to the representation and classification, we propose an adaptive joint block-weighted collaborative representation-based classification (JBW_CRC) method to effectively exploit the similarity and distinctiveness of different blocks. In JBW_CRC, samples are divided into different blocks and each block of the query sample is represented as a feature vector. Each feature vector is coded on its related block dictionary, which considers the similarity among the feature vectors. Additionally, the distinctiveness …
A New Word-Based Compression Model Allowing Compressed Pattern Matching,
2017
TÜBİTAK
A New Word-Based Compression Model Allowing Compressed Pattern Matching, Hali̇l Nusret Buluş, Aydin Carus, Altan Mesut
Turkish Journal of Electrical Engineering and Computer Sciences
In this study a new semistatic data compression model that has a fast coding process and that allows compressed pattern matching is introduced. The name of the proposed model is chosen as tagged word-based compression algorithm (TWBCA) since it has a word-based coding and word-based compressed matching algorithm. The model has two phases. In the first phase a dictionary is constructed by adding a phrase, paying attention to word boundaries, and in the second phase compression is done by using codewords of phrases in this dictionary. The first byte of the codeword determines whether the word is compressed or not. …
Feedback Delay Compensation Of A Visual Servoing System Using A Piecewise Continuous And Current Estimator-Based Observer,
2017
TÜBİTAK
Feedback Delay Compensation Of A Visual Servoing System Using A Piecewise Continuous And Current Estimator-Based Observer, Abdeldafia Mohammed, Haoping Wang, Yang Tian
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a piecewise continuous current estimator-based observer is proposed to estimate a plant's states using sampled and delayed measurements. The advantage of the proposed technique is simple in terms of analysis and design. Moreover, the proposed observer can compensate the time delay when the delay equals the sampling period. Comprehensive stability analysis of the designed observer is performed. In addition, to assess the efficiency and effectiveness of the proposed observer, a numerical comparative study with a Kalman filter-based observer is established and the simulation results are demonstrated.
