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

Computer Engineering Commons™

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

Articles 2161 - 2190 of 3106

Full-Text Articles in Computer Engineering

A Sampling-Based Method Using An Improved Nonparametric Density Estimator For Probabilistic Harmonic Load Flow Calculation, Farshid Nasrfard-Jahromi, Mohammad Mohammadi Jan 2016

A Sampling-Based Method Using An Improved Nonparametric Density Estimator For Probabilistic Harmonic Load Flow Calculation, Farshid Nasrfard-Jahromi, Mohammad Mohammadi

Turkish Journal of Electrical Engineering and Computer Sciences

Harmonic distortion in electrical power systems is responsible for several technical problems. Harmonic load flow (HLF) methods have been employed in order to predict and solve many of the problems from a deterministic point of view. Moreover, methods based on probability theory have been developed to deal with the uncertainties in power systems and the random nature of harmonics. Unfortunately, since many of these methods are based on linearized models or some simplifying assumptions, they do not have acceptable accuracy. This paper proposes the use of an efficient sampling method, median Latin hypercube sampling, combined with an improved kernel density …


A Fast And Accurate Algorithm For Eye Opening Or Closing Detection Based On Local Maximum Vertical Derivative Pattern, Marzieh Tafreshi, Ali Mohammad Fotouhi Jan 2016

A Fast And Accurate Algorithm For Eye Opening Or Closing Detection Based On Local Maximum Vertical Derivative Pattern, Marzieh Tafreshi, Ali Mohammad Fotouhi

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a fast and accurate algorithm is proposed to recognize open and closed eye states. In the proposed algorithm, first a hierarchical preprocessing stage is used to detect eye areas. This stage employs Haar features to detect face area, color, and intensity mappings to extract eye candidate areas, and some simple geometrical relations for a final decision of the eye regions. In the second stage of the algorithm for detecting eye state, a new proposed descriptor based on a histogram of local maximum vertical derivative patterns in eye areas is extracted and applied to a support vector machine …


Design And Implementation Of A Digital Mppt Controller For A Photovoltaic Panel, Djamel Eddine Tourqui, Achour Betka, Atallah Smaili, Tayeb Allaoui Jan 2016

Design And Implementation Of A Digital Mppt Controller For A Photovoltaic Panel, Djamel Eddine Tourqui, Achour Betka, Atallah Smaili, Tayeb Allaoui

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a simplified design and hardware implementation of a digital maximum power point tracking (MPPT) controller for a photovoltaic (PV) panel using PIC microcontroller 16F877A embedded technology. The 3 most well-known algorithms, perturb & observe, hill-climbing, and incremental conductance, are considered and analyzed from a practical implementation point of view. The control board was developed using simple circuits and tested under resistive load conditions lower than the load of the maximum power point. The MPPT controller proved its effectiveness, providing maximum power to the load under changing weather conditions.


Real-Time Motorized Electrical Hospital Bed Control With Eye-Gaze Tracking, Nesri̇n Aydin Atasoy, Abdullah Çavuşoğlu, Ferhat Atasoy Jan 2016

Real-Time Motorized Electrical Hospital Bed Control With Eye-Gaze Tracking, Nesri̇n Aydin Atasoy, Abdullah Çavuşoğlu, Ferhat Atasoy

Turkish Journal of Electrical Engineering and Computer Sciences

Patients with motor neuron disease and most terminal patients cannot use their hands or arms, and so they need another person for their all needs. However, the mental functions and memories of such patients are generally sound, and they can control their eyes. Using an eye-gaze tracking technique, we have realized a real-time system for such patients. The system controls a motorized electrical hospital bed (EHB) by eye gaze with 4 degrees of freedom, using a low-cost webcam. Contactless systems that require calibration cannot be used for EHB control. The system developed in this work does not require any calibration …


Parallel Decoding For Lattice Reduction-Aided Mimo Receiver, Madurakavi Karthikeyan, Djagadeesan Saraswady Jan 2016

Parallel Decoding For Lattice Reduction-Aided Mimo Receiver, Madurakavi Karthikeyan, Djagadeesan Saraswady

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a modified lattice reduction (LR) for parallel decoding (PD) in multiple input and multiple output (MIMO) systems. Compared with the conventional methods, without any performance loss, the symbols can be estimated in parallel using this LR-PD algorithm. This parallel decoding is achieved through the proposed postrotation matrix. Among the various LR algorithms, LLL has been considered in the analysis of this postrotation matrix. However, this can be applied to any other LR algorithms without any modifications. In simulations, we show that with a minimal number of extra arithmetic operations and without any significant loss in …


Effect Of Load Increase And Power System Stabilizer On Stability Delay Margin Of A Generator Excitation Control System, Şahi̇n Sönmez, Saffet Ayasun Jan 2016

Effect Of Load Increase And Power System Stabilizer On Stability Delay Margin Of A Generator Excitation Control System, Şahi̇n Sönmez, Saffet Ayasun

Turkish Journal of Electrical Engineering and Computer Sciences

This paper studies the impact of load increase and a power system stabilizer (PSS) on the stability delay margin of a single-machine-infinite-bus system including an automatic voltage regulator. An analytical method is proposed to determine the stability delay margin of the excitation control system. The proposed method first eliminates transcendental terms in the characteristic equation of the excitation system without making any approximation and transforms the transcendental characteristic equation into a regular polynomial. The key result of the elimination process is that the real roots of the new polynomial correspond to the imaginary roots of the transcendental characteristic equation. With …


An Optimized Embedded Adder For Digital Signal Processing Applications, Kala Bharathan, Seshasayanan Ramachandran Jan 2016

An Optimized Embedded Adder For Digital Signal Processing Applications, Kala Bharathan, Seshasayanan Ramachandran

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an embedded logic full adder (PRO-FA) circuit in transistor level is proposed that reduces logic complexity, consumes low power, and is low area. The design is implemented for 1 bit and then is further extended to 64 bits. The area obtained for 1-bit PRO-FA is 2.85 $ {\mu }{m}^{{2}}$ and is built using only 13 transistors. The PDP of the proposed adder is ${459.4\times }{{10}}^{{-18}} Ws $ and ADP is 128.25 $\mu {m}^{{2}}ps $ and is compared with the earlier reported designs. Furthermore, a 16-, 32-, 64-bit both linear and square-root carry select adder/subtractor (CSLAS) structure is …


Dynamic Characteristics Of An Isolated Self-Excited Synchronous Reluctance Generator Driven By A Wind Turbine, Mosaad Mohiedden Ali, Said Mahmoud Allam, Talaat Hamdan Abdel-Moneim Jan 2016

Dynamic Characteristics Of An Isolated Self-Excited Synchronous Reluctance Generator Driven By A Wind Turbine, Mosaad Mohiedden Ali, Said Mahmoud Allam, Talaat Hamdan Abdel-Moneim

Turkish Journal of Electrical Engineering and Computer Sciences

This paper studies the dynamic characteristics of an isolated three-phase self-excited synchronous reluctance generator (SESRG) driven by a variable-speed wind turbine under different operating conditions. Self-excitation is achieved via capacitors connected across the generator terminals. A detailed mathematical modeling of the proposed self-excited wind generation system is presented. The proposed analysis is based on the dynamic qd-axis model of the SESRG. Magnetic saturation is taken into account and is assumed to be confined to the direct axis and is accounted for as a variable direct-axis magnetizing reactance. Effect of wind-speed variation, excitation-capacitance variation, and loading-conditions variation on the generated output …


Impact Of Repeaters On The Performance Of Indoor Visible Light Communications, Refi̇k Çağlar Kizilirmak Jan 2015

Impact Of Repeaters On The Performance Of Indoor Visible Light Communications, Refi̇k Çağlar Kizilirmak

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we examine the performance of fixed gain amplify-and-forward repeaters for visible light communication (VLC) systems. We present the wireless optical channel model for VLC with the repeater and we evaluate the bit-error-rate (BER) performance for pulse-position modulation over the multipath channel with additive white Gaussian noise. The results reveal that when a repeater is placed, both the BER and the illuminance performance can be improved at any location in a typical office space. The benefit of VLC repeaters is also discussed when the channel from the source to the destination is shadowed. It is found that when …


Impact Of Large-Scale Installation Of Led Lamps In A Distribution System, Sohel Uddin, Hussain Sharef, Olav Krause, Azah Mohamed, Mohammad Abdul Hannan, Naz Niamul Islam Jan 2015

Impact Of Large-Scale Installation Of Led Lamps In A Distribution System, Sohel Uddin, Hussain Sharef, Olav Krause, Azah Mohamed, Mohammad Abdul Hannan, Naz Niamul Islam

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this paper was to examine the utilization of a large number of nonlinear light emitting diode (LED) lamps in a distribution system and its impact on system power quality. Initially, harmonic and others electrical characteristics were identified by carrying out an experiment on four types of LED lamps available on the local market. On the basis of the identified characteristics, a new LED lamp model was developed in MATLAB Simulink. This model is called the time-dependent current source model and gives more accurate results than the fixed current source model. Then this model was applied to a …


Simulation Of Locating Buried Objects Via Fringe Pattern-Based Measurements In An Optical Fiber Sensor-Integrated Continuous-Wave Ground-Penetrating Radar System, Asaf Behzat Şahi̇n, Hati̇ce Gonca Bulur Jan 2015

Simulation Of Locating Buried Objects Via Fringe Pattern-Based Measurements In An Optical Fiber Sensor-Integrated Continuous-Wave Ground-Penetrating Radar System, Asaf Behzat Şahi̇n, Hati̇ce Gonca Bulur

Turkish Journal of Electrical Engineering and Computer Sciences

A new ground-penetrating radar system that can determine the depth and position of a buried metal cylinder, which is the combination of an optical fiber sensor (OFS), continuous-wave transmitter, and optical communication link, is proposed and simulated in the MATLAB and Optiwave program packages. Employing an optical sensor instead of a standard radio frequency (RF) receiver offers the advantage of preventing electromagnetic interference along the sensor's main unit cable and lower amplification noise. In this paper, the electric field distribution at the OFS due to reflections from the soil surface and the buried object is obtained mathematically using Green's function. …


Intelligent Text Classification System Based On Self-Administered Ontology, Manoj Manuja, Deepak Garg Jan 2015

Intelligent Text Classification System Based On Self-Administered Ontology, Manoj Manuja, Deepak Garg

Turkish Journal of Electrical Engineering and Computer Sciences

Over the last couple of decades, web classification has gradually transitioned from a syntax- to semantic-centered approach that classifies the text based on domain ontologies. These ontologies are either built manually or populated automatically using machine learning techniques. A prerequisite condition to build such systems is the availability of ontology, which may be either full-fledged domain ontology or a seed ontology that can be enriched automatically. This is a dependency condition for any given semantics-based text classification system. We share the details of a proof of concept of a web classification system that is self-governed in terms of ontology population …


Moving As A Whole: Multirobot Traveling Problem Constrained By Connectivity, Yun Wang, Cheng Hu Jan 2015

Moving As A Whole: Multirobot Traveling Problem Constrained By Connectivity, Yun Wang, Cheng Hu

Turkish Journal of Electrical Engineering and Computer Sciences

A multirobot system provides many advantages over a single robot. In certain situations, robots need to maintain global connectivity while proceeding through tasks such as traveling to spots of interest in an area. This paper formulates the problem of multiple robots traveling while constrained by connectivity and analyzes the limits of increase in total traveling distance (TTD) caused by connectivity constraints. A connection condition is proposed and proven, which can be used to direct the design of solutions. Two algorithms satisfying the connection condition, connected nearest neighbor (CNN) and bold Lin-Kernighan heuristic (B-LKH), are proposed to solve this problem, which …


Exact Solution Of Conducting Half Plane Problems In Terms Of A Rapidly Convergent Series And An Application Of The Multiplicative Calculus, Ali̇ Uzer Jan 2015

Exact Solution Of Conducting Half Plane Problems In Terms Of A Rapidly Convergent Series And An Application Of The Multiplicative Calculus, Ali̇ Uzer

Turkish Journal of Electrical Engineering and Computer Sciences

The problem of cylindrical wave incidence on a conducting half plane has been considered. A modal solution for Green's function of the problem is transformed into contour integral representations in a complex plane. Some contour deformations and changes of variables are then made for the integrals. Finally, the resultant integrals are transformed back into a series, which converges rapidly to the exact solution when the observation angles are close to the reflection/shadow boundaries (RSBs) of the conducting half plane. The multiplicative calculus is employed in deriving an expression that can be used for obtaining approximate solutions when the observation angles …


Capacitive Sensor Supporting Multiple Touch Switches Using A Resistor String, Kwangsu Seong Jan 2015

Capacitive Sensor Supporting Multiple Touch Switches Using A Resistor String, Kwangsu Seong

Turkish Journal of Electrical Engineering and Computer Sciences

In a low-cost integrated circuit (IC) chip, the packaging cost is a considerable portion of the total manufacturing cost of the chip. As the packaging cost is directly related to the total number of I/O pins, it is highly desirable to minimize the number of I/O pins while maintaining the same functionality. We propose a capacitive sensor that supports multiple touch switches with only two IC pins. The electrode plates of the touch switches are placed at the ends of a resistor string and between every two adjacent resistors in the resistor string. The proposed method measures rise times at …


Optimal Backup Parent Pools For Resilient Multicast Trees On Peer-To-Peer Networks, Emrullah Turhan Tunali, Müge Sayit Jan 2015

Optimal Backup Parent Pools For Resilient Multicast Trees On Peer-To-Peer Networks, Emrullah Turhan Tunali, Müge Sayit

Turkish Journal of Electrical Engineering and Computer Sciences

Due to churn as well as node and link failures in peer-to-peer (P2P) networks, providing resilient multicast is a challenging issue, particularly for overlay trees. In this work, we first study analytical properties of the backup parent pool that aims at improving the resilience of overlay multicast trees in P2P video streaming. We then present a novel greedy degree-constrained multicast tree construction algorithm that addresses the tradeoffs between maximizing resiliency, maximizing bandwidth utilization, and minimizing delay. The choice of essential design parameters is studied together with seamlessness of the streaming under a variety of fault scenarios. Simulation results indicate that …


Performance Evaluation Of Three Phase Srf-Pll And Maf-Srf-Pll, Anirban Ghoshal, Vinod John Jan 2015

Performance Evaluation Of Three Phase Srf-Pll And Maf-Srf-Pll, Anirban Ghoshal, Vinod John

Turkish Journal of Electrical Engineering and Computer Sciences

Synchronous reference frame phase locked loop (SRF-PLL) is a well established technique used for maintaining synchronism of a grid connected VSI with an electric grid. Many methods of PLL are present in the literature to achieve improved performance under nonideal grid condition. These solutions are based on SRF-PLL structure along with some modification to achieve improved performance. It is observed that faster and better performance are achieved at the expense of more computations. Moving average filter (MAF) SRF-PLL structure is one such solution that consumes less resources and gives a reasonably fast response. In this work the performance of a …


An Elegant Emergence Of Optimal Siting And Sizing Of Multiple Distributed Generators Used For Transmission Congestion Relief, Rajamanickam Manickaraj Sasiraja, Velu Suresh Kumar, Sankaralingam Ponmani Jan 2015

An Elegant Emergence Of Optimal Siting And Sizing Of Multiple Distributed Generators Used For Transmission Congestion Relief, Rajamanickam Manickaraj Sasiraja, Velu Suresh Kumar, Sankaralingam Ponmani

Turkish Journal of Electrical Engineering and Computer Sciences

After the implementation of deregulation in a power system, an appreciable volume of renewable energy sources is used to generate electric power. Even though they are intended to improve the reliability of the power system, the unpredictable outages of generators or transmission lines, an impulsive increase in demand, and failures of other equipment lead to congestion in one or more transmission lines. There are several ways to alleviate this transmission congestion, such as the installation of new generation facilities in the place where the demand is high, the addition of a new transmission facility, generation rescheduling, and curtailment of load …


Hybrid Adaptive Neuro-Fuzzy B-Spline--Based Sssc Damping Control Paradigm Using Online System Identification, Laiq Khan, Rabiah Badar Jan 2015

Hybrid Adaptive Neuro-Fuzzy B-Spline--Based Sssc Damping Control Paradigm Using Online System Identification, Laiq Khan, Rabiah Badar

Turkish Journal of Electrical Engineering and Computer Sciences

B-spline membership functions have produced promising results in the field of signal processing and control due to their local control property. This work explores the potential of B-spline--based adaptive neuro-fuzzy wavelet control to damp low frequency power system oscillations using a static synchronous series compensator (SSSC). A comparison of direct and indirect adaptive control based on hybrid adaptive B-spline wavelet control (ABSWC) is presented by introducing the online identification block. ABSWC with identification (ABSWCI) provides the sensitivity information of the plant needed to control the system. The parameters of the control and identification block are updated online using a gradient …


An Accelerated And Accurate Three-Dimensional Ray Tracing Using Red-Black Tree With Facet Mining And Object Bouncing Techniques, Mohammad Jakirul Islam, Ahmed Wasif Reza, Kamarul Ariffin Noordin, Kaharudin Dimyati, Abu Sulaiman Mohammad Zahid Kausar Jan 2015

An Accelerated And Accurate Three-Dimensional Ray Tracing Using Red-Black Tree With Facet Mining And Object Bouncing Techniques, Mohammad Jakirul Islam, Ahmed Wasif Reza, Kamarul Ariffin Noordin, Kaharudin Dimyati, Abu Sulaiman Mohammad Zahid Kausar

Turkish Journal of Electrical Engineering and Computer Sciences

Recent trends show that it is a major challenge to predict the exact propagation path accurately and efficiently for three-dimensional (3D) indoor environments. Therefore, this study introduces a new 3D ray tracing algorithm based on a red-black tree with facet mining and object bouncing techniques. The red-black tree data structure offers a faster object searching operation while repeatedly performing intersection tests. On the other hand, extensive ray-facet intersection tests can be eliminated by using object and facet bouncing techniques, whereas the facet mining makes it easier to trace the transmitted ray paths accurately. The proposed method is compared with ray …


Mppt Of Pv Array Using Stepped-Up Chaos Optimization Algorithm, Lihua Wang, Xueye Wei, Yuqin Shao, Tianlong Zhu, Junhong Zhang Jan 2015

Mppt Of Pv Array Using Stepped-Up Chaos Optimization Algorithm, Lihua Wang, Xueye Wei, Yuqin Shao, Tianlong Zhu, Junhong Zhang

Turkish Journal of Electrical Engineering and Computer Sciences

In order to achieve maximum efficiency, a maximum power point tracking (MPPT) scheme should be applied in photovoltaic systems. Among all the MPPT schemes, the chaos optimization scheme is one of the hot topics in recent years. In this study, a novel stepped-up chaos optimization algorithm is presented. A chaos mapping $x_{n+1} =\mu \sin (\pi x_{n} )$ is used as a chaos generator to produce a chaos variable. In the process of MPPT, a coarse search is done to find the current optimal solution in a certain range, and then a fine search reduces the space of optimized variables. Compared …


A Comparative Performance Evaluation Of Various Approaches For Liver Segmentation From Spir Images, Evgi̇n Göçeri̇, Mehmet Zübeyi̇r Ünlü, Oğuz Di̇cle Jan 2015

A Comparative Performance Evaluation Of Various Approaches For Liver Segmentation From Spir Images, Evgi̇n Göçeri̇, Mehmet Zübeyi̇r Ünlü, Oğuz Di̇cle

Turkish Journal of Electrical Engineering and Computer Sciences

Developing a robust method for liver segmentation from magnetic resonance images is a challenging task because of the similar intensity values between adjacent organs, the geometrically complex liver structure, and injection of contrast media. Most importantly, a high anatomical variability of a healthy or diseased liver is a major challenge in defining the exact boundaries of the liver. Several artifacts of pulsation, motion, and partial volume effects are also among the variety of factors that make automatic liver segmentation difficult. In this paper, we present an overview of liver segmentation methods in magnetic resonance images and show comparative results of …


A Mobile And Web Application-Based Recommendation System Using Color Quantization And Collaborative Filtering, Fi̇dan Kaya, Gürel Yildiz, Adnan Kavak Jan 2015

A Mobile And Web Application-Based Recommendation System Using Color Quantization And Collaborative Filtering, Fi̇dan Kaya, Gürel Yildiz, Adnan Kavak

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a recommendation system based on a mobile and web application is proposed for indoor decoration. The main contribution of this work is to apply two-stage filtering using linear matching and collaborative filtering to make recommendations. In the mobile application part, the image of the medium captured by a mobile phone is analyzed using color quantization methods, and these color analysis results along with other user-defined parameters such as height, width, and type of the product are sent to the web server. In the web application part, a large data set is first filtered via linear matching in …


Mras-Based Sensorless Speed Backstepping Control For Induction Machine, Using A Flux Sliding Mode Observer, Mohamed Moutchou, Ahmed Abbou, Hassan Mahmoudi Jan 2015

Mras-Based Sensorless Speed Backstepping Control For Induction Machine, Using A Flux Sliding Mode Observer, Mohamed Moutchou, Ahmed Abbou, Hassan Mahmoudi

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an induction machine rotor speed and rotor flux control using a sensorless backstepping control scheme is discussed. The most interesting point of this technique is that it deals with the nonlinearity of a high-order system by using the virtual control variable to make this system simple, and thus the control outputs can be derived step by step through appropriate Lyapunov functions. To avoid the use of a mechanical sensor, the rotor speed estimation is made by an observer using the model reference adaptive system (MRAS) technique; in order to estimate rotor flux, a sliding mode observer is …


Designing And Implementing A Reliable Thermal Monitoring System Based On The 1-Wire Protocol On Fpga For A Leo Satellite, Reza Omidi Gosheblagh, Karim Mohammadi Jan 2015

Designing And Implementing A Reliable Thermal Monitoring System Based On The 1-Wire Protocol On Fpga For A Leo Satellite, Reza Omidi Gosheblagh, Karim Mohammadi

Turkish Journal of Electrical Engineering and Computer Sciences

Thermal control and monitoring is one of the most important factors in the design of satellite systems. An appropriate thermal design should make sure that the satellite's sensitive components remain in their nominated range, even under the vacuum condition of outer space. To achieve this purpose, a reliable and stable monitoring system is required. This paper proposes a monitoring system based on the 1-wire protocol, which provides the reliability requirements in the sensor networking and bus controller sections. In the networking section, we outline some practical topologies and discuss on their complexity and reliability. Despite the fact that the point-to-point …


Temporal Logic Extension For Self-Referring, Nonexistence, Multiple Recurrence, And Anterior Past Events, Şadi̇ Evren Şeker Jan 2015

Temporal Logic Extension For Self-Referring, Nonexistence, Multiple Recurrence, And Anterior Past Events, Şadi̇ Evren Şeker

Turkish Journal of Electrical Engineering and Computer Sciences

This study focuses on the possible extensions of current temporal logics. In this study, 4 extensions are proposed: self-referring events, nonexisting events, multiple recurrence of events, and an improvement on anterior past events. Each of these extensions is on a different level of temporal logics. The main motivation behind the extensions is the temporal analysis of Turkish. Similar to temporal logic studies built on other natural languages, like French, Ukrainian, Italian, Korean, English, or Romanian, this is the first time that the Turkish language has been deeply questioned in the sense of computable temporal logic using the view of a …


Discrete-Time Modeling Of Hamiltonian Systems, Yaprak Yalçin, Leyla Gören Sümer, Salman Kurtulan Jan 2015

Discrete-Time Modeling Of Hamiltonian Systems, Yaprak Yalçin, Leyla Gören Sümer, Salman Kurtulan

Turkish Journal of Electrical Engineering and Computer Sciences

The problem of discrete-time modeling of the lumped-parameter Hamiltonian systems is considered for engineering applications. Hence, a novel gradient-based method is presented, exploiting the discrete gradient concept and the forward Euler discretization under the assumption of the continuous Hamiltonian model is known. It is proven that the proposed discrete-time model structure defines a symplectic difference system and has the energy-conserving property under some conditions. In order to provide alternate discrete-time models, 3 different discrete-gradient definitions are given. The proposed models are convenient for the design of sampled-data controllers. All of the models are considered for several well-known Hamiltonian systems and …


Mersenne Twister-Based Rfid Authentication Protocol, Mehmet Hi̇lal Özcanhan, Gökhan Dalkiliç Jan 2015

Mersenne Twister-Based Rfid Authentication Protocol, Mehmet Hi̇lal Özcanhan, Gökhan Dalkiliç

Turkish Journal of Electrical Engineering and Computer Sciences

This work presents an ultra-lightweight, cryptographic, mutual authentication protocol for radio-frequency identification (RFID) tags. The proposed scheme is more secure than its predecessors. The vulnerabilities of previous schemes based on triangular functions and rotation have been demonstrated in traditional and rotational cryptanalysis. In this paper, we summarize the successful attacks on previous schemes and demonstrate further attacks on 3 recent ultra-lightweight protocols. Next, we present a proposal that resists all of the known passive attacks. The proposal obeys the properties and rules of addition-rotation-XOR with constants systems. The proposed scheme inserts parts of advanced encryption standard S-boxes into the temperings …


Bandwidth Extension Of Narrowband Speech In Log Spectra Domain Using Neural Network, Sara Pourmohammadi, Mansour Vali, Mohsen Ghadyani Jan 2015

Bandwidth Extension Of Narrowband Speech In Log Spectra Domain Using Neural Network, Sara Pourmohammadi, Mansour Vali, Mohsen Ghadyani

Turkish Journal of Electrical Engineering and Computer Sciences

In recent years, there have been significant advances in communication technology, but speech signals still suffer from low perceived quality caused by bandwidth limitations of telephone networks. The bandwidth extension (BWE) approach adds high-frequency components of the speech signal to band-limited telephone speech and increases speech perception significantly. In this work, we develop a new method for representation of vocal tract filter coefficients using log of filter bank energy (LFBE) parameters as an alternative for mel-frequency cepstral coefficients (MFCCs). This approach is based on a strong correlation between the spectral components of low- and high-band spectrums. Furthermore, the performances of …


A Particle Swarm Optimization-Based Approach To Achieve Optimal Design And Operation Strategy Of Standalone Hybrid Energy Systems, Mahram Ghazvini, Ali Abbaspour Tehrani Fard, Mahmud Fotuhi Firuzabad Jan 2015

A Particle Swarm Optimization-Based Approach To Achieve Optimal Design And Operation Strategy Of Standalone Hybrid Energy Systems, Mahram Ghazvini, Ali Abbaspour Tehrani Fard, Mahmud Fotuhi Firuzabad

Turkish Journal of Electrical Engineering and Computer Sciences

As a cost-effective and reliable alternative to supply remote areas, standalone hybrid energy systems (HESs) are recently under investigation to address various concerns associated with technical, financial, and environmental issues. This paper presents a comprehensive algorithm that can simultaneously optimize the component size, operation strategy, and slope of the photovoltaic panels of a standalone HES using an improved variant of particle swarm optimization (PSO), designated as the passive congregation PSO. A new operation strategy is proposed based on the set points of the control system. The optimization algorithm determines the optimal values of the set points to efficiently optimize the …