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

Physical Sciences and Mathematics Commons

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

Articles 31 - 60 of 75

Full-Text Articles in Physical Sciences and Mathematics

Determination Of Autoregressive Model Orders For Seizure Detection, Serap Aydin Jan 2010

Determination Of Autoregressive Model Orders For Seizure Detection, Serap Aydin

Turkish Journal of Electrical Engineering and Computer Sciences

In the present study, a step-wise least square estimation algorithm (SLSA), implemented in a Matlab package called as ARfit, has been newly applied to clinical data for estimation of the accurate Auto-Regressive (AR) model orders of both normal and ictal EEG series where the power spectral density (PSD) estimations are provided by the Burg Method. The ARfit module is found to be usefull in comparison to a large variety of traditional methods such as Forward Prediction Error (FPE), Akaike's Information Criteria (AIC), Minimum Description Lenght (MDL), and Criterion of Autoregressive Transfer function (CAT) for EEG discrimination. According to tests, the …


Effect Of Transformer On Stochastic Estimation Of Voltage Sag Due To Faults In The Power System: A Pscad/Emtdc Simulation, Nita R. Patne, K. L. Thakre Jan 2010

Effect Of Transformer On Stochastic Estimation Of Voltage Sag Due To Faults In The Power System: A Pscad/Emtdc Simulation, Nita R. Patne, K. L. Thakre

Turkish Journal of Electrical Engineering and Computer Sciences

Voltage sags in the electric power system are mostly due to faults in the power system. Voltage sag is characterized by its magnitude (the retained voltage), phase-angle jump, unbalance in the sag in the three phases, and duration. Type of transformers in the electrical system is the important parameter influencing the characteristic of sag at the node where sensitive loads are connected. For sensitive loads it is necessary to estimate how many times in a year the voltage at their terminal will experience sag to avoid tripping of operation. In this paper the effect of transformer on stochastic estimation of …


Building Linear Parameter Varying Models Using Adaptation, For The Control Of A Class Of Nonlinear Systems, Coşku Kasnakoğlu Jan 2010

Building Linear Parameter Varying Models Using Adaptation, For The Control Of A Class Of Nonlinear Systems, Coşku Kasnakoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a novel method is proposed for constructing linear parameter varying (LPV) system models through adaptation. For a class of nonlinear systems, an LPV model is built using its linear part, and its coefficients are considered as time-varying parameters. The variation in time is controlled by an adaptation scheme with the goal of keeping the trajectories of the LPV system close to those of the original nonlinear system. Using the LPV model as a surrogate, a dynamical controller is built by utilizing self-scheduling methods for LPV systems, and it is shown that this controller will indeed stabilize the …


Differential Power Analysis Resistant Hardware Implementation Of The Rsa Cryptosystem, Kekli̇k Alpteki̇n Bayam, Berna Örs Jan 2010

Differential Power Analysis Resistant Hardware Implementation Of The Rsa Cryptosystem, Kekli̇k Alpteki̇n Bayam, Berna Örs

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, RSA cryptosystem was implemented on hardware, then modified to be resistant against Differential Power Analysis attacks by using the Randomized Table Window method. This is the first FPGA realization of an algorithmic countermeasure which makes RSA resistant to power analysis attacks. Modular exponentiation is realized with Montgomery Modular Multiplication. The Montgomery modular multiplier has been realized with Carry-Save Adders. Carry-Save representation has been used throughout the RSA encryption algorithm. The primarily implemented RSA architecture prevents the extraction of the secret key using Simple Power Analysis attacks. When comparing the protected implementation with the unprotected, it can be …


A Novel Square-Root Domain Realization Of First Order All-Pass Filter, Si̇nem Ölmez, Uğur Çam Jan 2010

A Novel Square-Root Domain Realization Of First Order All-Pass Filter, Si̇nem Ölmez, Uğur Çam

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new square-root domain, first order, all-pass filter based on the MOSFET square law is presented. The proposed filter is designed by using nonlinear mapping on the state variables of a state space description of the transfer function. To the best knowledge of the authors, the filter is the first square-root domain first order all-pass structure designed by using state space synthesis method in the literature. The center frequency of the all-pass filter is not only attainable at megahertz frequencies but also tunable by an external bias current. The proposed filter operated 2.5 V supply voltage is …


Stator Resistance Estimation Using Ann In Dtc Im Drives, Mustafa Aktaş, H. İbrahi̇m Okumuş Jan 2010

Stator Resistance Estimation Using Ann In Dtc Im Drives, Mustafa Aktaş, H. İbrahi̇m Okumuş

Turkish Journal of Electrical Engineering and Computer Sciences

Torque control of induction motors (IM) requires accurate estimation of the flux in the motor. But the flux estimate, when estimated from the stator circuit variables, is highly dependent on the stator resistance of the IM. As a result, the flux estimate is prone to errors due to variation in the stator resistance, especially at low stator frequencies. In this paper, an Artificial Neural Network (ANN) is used to adjust the stator resistance of an IM. A back propagation training algorithm was used in training the neural network for the simulation. The proposed ANN resistance estimator has shown good performance …


Stochastic Stability Of The Discrete-Time Constrained Extended Kalman Filter, Levent Özbek, Esi̇n Köksal Babacan, Murat Efe Jan 2010

Stochastic Stability Of The Discrete-Time Constrained Extended Kalman Filter, Levent Özbek, Esi̇n Köksal Babacan, Murat Efe

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, stability of the projection-based constrained discrete-time extended Kalman filter (EKF) as applied to nonlinear systems in a stochastic framework has been studied. It has been shown that like the unconstrained EKF, the estimation error of the EKF with known constraints on the states remains bounded when the initial error and noise terms are small, and the solution of the Riccati difference equation remains positive definite and bounded. Stability results are verified and performance of the constrained EKF is demonstrated through simulations on a nonlinear engineering example.


An Rfid Based Indoor Tracking Method For Navigating Visually Impaired People, Ruşen Öktem, Eli̇f Aydin Jan 2010

An Rfid Based Indoor Tracking Method For Navigating Visually Impaired People, Ruşen Öktem, Eli̇f Aydin

Turkish Journal of Electrical Engineering and Computer Sciences

This paper tackles the RFID based tracking problem in an obscured indoor environment. The proposed solution is an integral part of a navigation aid for guiding visually impaired people in a store. It uses RF signal strengths and is based on the Bayes Decision Theory. An observation vector is formed by received radio signal strength indication values, transmitted from three transmitters at distinct frequencies in the UHF band. The indoor area is divided into square grids, where each grid is considered as a class. The problem of tracking is expressed as classifying the observed radio signal strengths to the most …


K-Anonymity Based Framework For Privacy Preserving Data Collection In Wireless Sensor Networks, Hayretdi̇n Bahşi̇, Albert Levi̇ Jan 2010

K-Anonymity Based Framework For Privacy Preserving Data Collection In Wireless Sensor Networks, Hayretdi̇n Bahşi̇, Albert Levi̇

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, k-anonymity notion is adopted to be used in wireless sensor networks (WSN) as a security framework with two levels of privacy. A base level of privacy is provided for the data shared with semi-trusted sink and a deeper level of privacy is provided against eavesdroppers. In the proposed method, some portions of data are encrypted and the rest is generalized. Generalization shortens the size of the data transmitted in the network causing energy saving at the cost of information loss. On the other hand, encryption provides anonymization with no information loss and without saving energy. Thus, there …


The Effect Of The Channel Reliability Factor In The Map Algorithm On Turbo Code Performance In Bluetooth Systems, Sali̇m Kahveci̇, İsmai̇l Kaya Jan 2010

The Effect Of The Channel Reliability Factor In The Map Algorithm On Turbo Code Performance In Bluetooth Systems, Sali̇m Kahveci̇, İsmai̇l Kaya

Turkish Journal of Electrical Engineering and Computer Sciences

The effects of the channel reliability factor on the performance of turbo decoders that use a maximum a posteriori probability algorithm are investigated for wireless communication fading channels, such as Bluetooth systems. The channel reliability factor is related to the channel signal-to-noise ratio. For various values of the channel reliability factor, the obtained performance curves of the maximum a posteriori probability algorithm are given for the case of DMx Bluetooth data packets. When the channel reliability factor increases, the bit-error-rate performance of the DMx Bluetooth data packets also increases over fading channels.


Relativistic Electromagnetism In Rotating Media, Pierre Hillion Jan 2010

Relativistic Electromagnetism In Rotating Media, Pierre Hillion

Turkish Journal of Electrical Engineering and Computer Sciences

This work concerns relativistic electromagnetism in a cylindrical Frenet-Serret frame. The tensor formalism of Maxwell's equations and electromagnetic fields in a vacuum is first developed in terms of cylindrical coordinates and afterwards applied to a rotating frame using the relativistic Trocheris-Takeno description of rotations. The metric ds^2 = g_{\mu \nu} dx^{\mu} dx^{\nu} of this frame is then obtained to find the determinant g of the g_{\mu \nu} matrix intervening in the relativistic Maxwell's equations, where the Greek indices take on the values 1,2,3,4. The propagation of harmonic cylindrical waves in rotating media is analyzed and it is shown that these …


A Power Quality Monitoring System Based On Matlab Server Pages, Bülent Vural, Ali̇ Kizil, Mehmet Uzunoğlu Jan 2010

A Power Quality Monitoring System Based On Matlab Server Pages, Bülent Vural, Ali̇ Kizil, Mehmet Uzunoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

The power quality (PQ) requirement is one of the most important issues for power companies and their customers. Continuously monitoring the PQ from remote and distributed centers will help to improve the PQ. In this study, a remote power quality monitoring system for low voltage sub-networks is developed using MATLAB Server Pages (MSP). MATLAB Server Pages, which is an open source technical web programming language, combines MATLAB with integrated J2EE specifications. The proposed PQ monitoring system uses the MATLAB HTML tag library and the data captured by the DAQ hardware to evaluate the Power Quality parameters. The proposed system can …


Nonlinear Dynamic Analysis Of Mitral Valve Doppler Signals: Surrogate Data Analysis, Esma Uzunhi̇sarcikli Jan 2010

Nonlinear Dynamic Analysis Of Mitral Valve Doppler Signals: Surrogate Data Analysis, Esma Uzunhi̇sarcikli

Turkish Journal of Electrical Engineering and Computer Sciences

In our study, the nonlinear dynamics of mitral valve Doppler signals from 32 healthy and 28 patients with mitral valve stenosis was evaluated using by the computation of Lyapunov exponents, correlation dimension values and surrogate data analysis. Two chaotic features are compared for healthy and patient subjects. It was found that the largest Lyapunov exponent and correlation dimension values derived from patient subjects were larger than that of healthy subjects (\rho < 0.005). Surrogate data analysis was performed to determine the chaotic dynamics of Doppler signals. It was observed that the original and surrogate data have similar spectral features. Receiver operating characteristic (ROC) curves were used to evaluate the nonlinearity character Area Under the curve (AUC) values were obtained as 0.99 and 0.978 for the largest Lyapunov exponent and correlation dimension values, respectively. According to these results, Doppler signals have a nonlinear dynamic property and the largest Lyapunov exponent. Correlation dimension features can be used to detect the change in blood flow velocity of patients with mitral valve stenosis.


Modeling And Simulation Strategies In High Frequency Surface Wave Radars, Levent Sevgi̇ Jan 2010

Modeling And Simulation Strategies In High Frequency Surface Wave Radars, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Surface Wave High Frequency Radars (SWHFR) are taken into account in the content of modeling and simulation challenges. Examples related to multi-mixed path surface wave propagation, radar cross section (RCS) prediction, and total radar echo showing target, clutter, noise, and interference are presented.


A Review Of High Frequency Surface Wave Radar For Detection And Tracking Of Ships, Tony Ponsford, Jian Wang Jan 2010

A Review Of High Frequency Surface Wave Radar For Detection And Tracking Of Ships, Tony Ponsford, Jian Wang

Turkish Journal of Electrical Engineering and Computer Sciences

In today's resource-driven economy, maritime nations are claiming economic borders that extend beyond the continental shelf or the 200 nautical mile (nm) Exclusive Economic Zone (EEZ). However, claiming such large economic area places responsibilities on the parent nation to exercise jurisdiction through surveillance and enforcement. The requirement to see beyond the horizon has long been a goal of maritime security forces. Today, this is largely dependent on cooperative vessels voluntarily communicating their intentions to local shore-side authorities, as well as on those vessel sightings reported by patrollers. Recent advances in technology provide maritime nations with options to provide more systematic …


Nonlinear Scattering At Hf: Prospects For Exploitation In Oth Radar Systems, Stuart Anderson Jan 2010

Nonlinear Scattering At Hf: Prospects For Exploitation In Oth Radar Systems, Stuart Anderson

Turkish Journal of Electrical Engineering and Computer Sciences

HF skywave `over-the-horizon' radars experience exceptionally high levels of clutter from the earth's surface as a consequence of their `look-down' propagation geometry. While Doppler processing is effective in separating aircraft echoes from the clutter, thereby enabling detection, the same does not always hold for slow moving targets. In particular, ship echoes occupy the same region of Doppler space as the sea clutter, so the likelihood of target echo obscuration is high. By exploiting the known dependence of the characteristic spectral form of the clutter Doppler spectrum on radar frequency and other parameters, HF radars can maximise the prospects for detectability …


Propagation Modeling And Path Loss Prediction Tools For High Frequency Surface Wave Radars, Gökhan Apaydin, Levent Sevgi̇ Jan 2010

Propagation Modeling And Path Loss Prediction Tools For High Frequency Surface Wave Radars, Gökhan Apaydin, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Propagation modeling and simulation approaches for the use of High Frequency Surface Wave Radar (HFSWR) are discussed. HFSWR uses vertically polarized surface waves along multi-mixed paths in the lower HF band (3 MHz - 15 MHz). Various numerical propagators are reviewed with an early analytical model. Split Step Fast Fourier Transformation, finite- difference, and finite-element solutions of the well-known one-way, forward propagation Parabolic Equation (PE) model are presented. MATLAB-based numerical propagation prediction tools based on these models are listed. Tests and comparisons among these analytical and numerical tools are given for some canonical surface wave propagation scenarios. The Millington effect …


New Approach Fpga-Based Implementation Of Discontinuous Svpwm}, Tole Sutikno, Auzani Jidin, Nik Rumzi Nik Idris Jan 2010

New Approach Fpga-Based Implementation Of Discontinuous Svpwm}, Tole Sutikno, Auzani Jidin, Nik Rumzi Nik Idris

Turkish Journal of Electrical Engineering and Computer Sciences

The discontinuous space vector pulse-width modulation (DSVPWM) is a well-known technique offering lower switching losses than continuous SVPWM. At the same, average switching frequency, or a switching frequency 1.5 times higher than utilized in continuous SVPWM, the discontinuous SVPWM results in lower current harmonic distortions than that obtained in continuous SVPWM at high modulation indices. This paper is concerned with the design and realization of new FPGA approach based a 5-segment discontinuous SVPWM operated at 40 kHz switching frequency. It will be shown that the implementation of the discontinuous SVPWM utilized in FPGA, to execute some complex tasks, is simplified …


A Small Scale Education Experiment Kit With Wind Generator-Pem Electrolyser System And Modelling, Özcan Atlam Jan 2010

A Small Scale Education Experiment Kit With Wind Generator-Pem Electrolyser System And Modelling, Özcan Atlam

Turkish Journal of Electrical Engineering and Computer Sciences

A small scale experiment wind energy kit is prepared in order to introduce renewable energy applications. The kit consists of a wind turbine with horizontal axis, a direct current (dc) motor as generator and variable wind excitation system. Performance characteristics of the wind system are defined for different wind speeds. It is found that at the highest 10 m/s wind excitation, the maximum turbine mechanical power from wind is about 0.30 W at 5.3 V., maximum output power of the generator is about 0.18 W and maximum electrical efficiency is about 7% at 4.27 V., wind turbine power coefficients C_p …


Fractional Order Sliding Mode Control With Reaching Law Approach, Mehmet Önder Efe Jan 2010

Fractional Order Sliding Mode Control With Reaching Law Approach, Mehmet Önder Efe

Turkish Journal of Electrical Engineering and Computer Sciences

Fractional order sliding mode control is studied in this paper. The control objectives are achieved by adopting the reaching law approach of sliding mode control. The main contribution of this work is to show that the philosophy of integer order sliding mode control is valid also for the systems represented by fractional order operators. A sufficient condition and its implications for stability are given. Matched and unmatched uncertainties are studied. The attractor nature of the switching manifold is analyzed together with a stable sliding subspace design condition. The claims are justified through a set of simulations and the results obtained …


A Model Based Nonlinear Adaptive Controller For The Passive Bilateral Telerobotic System, Ufuk Özbay, Erkan Zergeroğlu, İlyas Kandemi̇r Jan 2010

A Model Based Nonlinear Adaptive Controller For The Passive Bilateral Telerobotic System, Ufuk Özbay, Erkan Zergeroğlu, İlyas Kandemi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

IIn this paper, we propose a new adaptive controller scheme for the bilateral telerobotic/teleoperation systems. The proposed controller achieves asymptotic tracking despite the parametric uncertainties associated with both master and slave robots while ensuring the passivity of the closed loop system. Extensive simulation studies are presented to illustrate the feasibility and efficiency of the proposed adaptive controller.


A Novel Algorithm For Sensorless Motion Control Of Flexible Structures, Islam Shoukry Mohammed Khalil, Emrah Deni̇z Kunt, Asif Sabanovic Jan 2010

A Novel Algorithm For Sensorless Motion Control Of Flexible Structures, Islam Shoukry Mohammed Khalil, Emrah Deni̇z Kunt, Asif Sabanovic

Turkish Journal of Electrical Engineering and Computer Sciences

This article demonstrates the validity of using an actuator as a single platform for measurements during a motion control assignment of flexible systems kept free from any kind of measurement. System acceleration level dynamics, parameters and interaction forces with the environment are coupled in an incident reaction torque that naturally rises when a flexible system is subjected to an action imposed by an attached actuator to the system. This work attempts to decouple each of the system parameters out of the incident coupled reaction torque at the interface point of the actuator with the flexible system by way of measurements …


Design And Evaluation Of A Linear Switched Reluctance Actuator For Positioning Tasks, António Espírito Santo, Rosário Calado, Carlos Cabrita Jan 2010

Design And Evaluation Of A Linear Switched Reluctance Actuator For Positioning Tasks, António Espírito Santo, Rosário Calado, Carlos Cabrita

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the development of a new linear switched reluctance actuator and confirms its applicability to perform positioning tasks. After the explanation of the actuator working principle and the presentation of its electromechanical topology, an analysis is accomplished using a finite elements tool. Based on the theoretical results, an experimental prototype that can develop 150 N was constructed. Its behaviour is observed under two different control methods implemented with microcontrollers. Initially, position is controlled applying a single pulse-driving scheme. Meanwhile, significant improvements are obtained with the introduction of a sliding-mode controller, allowing movements with 1 mm of resolution.


Using Covariates For Improving The Minimum Redundancy Maximum Relevance Feature Selection Method, Olcay Kurşun, Cemal Okan Şakar, Oleg Favorov, Ni̇zametti̇n Aydin, Sadik Fi̇kret Gürgen Jan 2010

Using Covariates For Improving The Minimum Redundancy Maximum Relevance Feature Selection Method, Olcay Kurşun, Cemal Okan Şakar, Oleg Favorov, Ni̇zametti̇n Aydin, Sadik Fi̇kret Gürgen

Turkish Journal of Electrical Engineering and Computer Sciences

Maximizing the joint dependency with a minimum size of variables is generally the main task of feature selection. For obtaining a minimal subset, while trying to maximize the joint dependency with the target variable, the redundancy among selected variables must be reduced to a minimum. In this paper, we propose a method based on recently popular minimum Redundancy-Maximum Relevance} (mRMR) criterion. The experimental results show that instead of feeding the features themselves into mRMR, feeding the covariates improves the feature selection capability and provides more expressive variable subsets.


Fast Computation Of Determination Of The Prime Implicants By A Novel Near Minimum Minimization Method, Fati̇h Başçi̇ftçi̇, Şi̇rzat Kahramanli Jan 2010

Fast Computation Of Determination Of The Prime Implicants By A Novel Near Minimum Minimization Method, Fati̇h Başçi̇ftçi̇, Şi̇rzat Kahramanli

Turkish Journal of Electrical Engineering and Computer Sciences

In this study proposed is an off-set-based direct-cover near-minimum minimization method for single-output Boolean functions represented in a sum-of-products form. To obtain the complete set of prime implicants including given on-cube (on-minterm), the proposed method uses off-cubes (off-minterms) expanded by this On-cube. The amount of temporary results produced by this method does not exceed the size of the off-set. To make fast computation, we used logic operations instead of standard operations. Expansion off-cubes, commutative absorption operations and intersection operations are realized by logic operations for fast computation. The proposed minimization method is tested on several different kinds of problems and …


Fuzzy Adaptive Neural Network Approach To Path Loss Prediction In Urban Areas At Gsm-900 Band, Türkan Erbay Dalkiliç, Berna Yeşi̇m Hanci, Ayşen Apaydin Jan 2010

Fuzzy Adaptive Neural Network Approach To Path Loss Prediction In Urban Areas At Gsm-900 Band, Türkan Erbay Dalkiliç, Berna Yeşi̇m Hanci, Ayşen Apaydin

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the results of the Adaptive-Network Based Fuzzy Inference System (ANFIS) for the prediction of path loss in a specific urban environment. A new algorithm based ANFIS for tuning the path loss model is introduced in this work. The performance of the path loss model which is obtained from proposed algorithm is compared to the Bertoni-Walfisch model, which is one of the best studied for propagation analysis involving buildings. This comparison is based on the mean square error between predicted and measured values. According to the indicated error criterion, the errors related to the predictions that are obtained …


Stpso: Strengthened Particle Swarm Optimization, Ai̇şe Zülal Şevkli̇, Fati̇h Erdoğan Sevi̇lgen Jan 2010

Stpso: Strengthened Particle Swarm Optimization, Ai̇şe Zülal Şevkli̇, Fati̇h Erdoğan Sevi̇lgen

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we present a novel approach to strengthen Particle Swarm Optimization (PSO). PSO is a population-based metaheuristic that takes advantage of individual memory and social cooperation in a swarm. It has been applied to a variety of optimization problems because of its simplicity and fast convergence. However, straightforward application of PSO suffers from premature convergence and lack of intensification around the local best locations. To rectify these problems, we modify update procedure for the best particle in the swarm and propose a simple and random moving strategy. We perform a Reduced Variable Neighborhood Search (RVNS) based local search …


Behaviors Of Real-Time Schedulers Under Resource Modification And A Steady Scheme With Bounded Utilization, Refi̇k Samet, Orhan Fi̇kret Duman Jan 2010

Behaviors Of Real-Time Schedulers Under Resource Modification And A Steady Scheme With Bounded Utilization, Refi̇k Samet, Orhan Fi̇kret Duman

Turkish Journal of Electrical Engineering and Computer Sciences

In this article we present an analysis for task models having random resource needs and different arrival patterns. In hard real-time environments like avionic systems or nuclear reactors, the inputs to the system are obtained from real world by using sensors. And it is highly possible for a task to have different resource needs for each period according to these changing conditions of real world. We made an analysis of schedulers for task models having random resources in each period. Since feasibility tests for usual task models are just limited to some specific schedulers and arrival patterns, we made our …


An Approach Based On Particle Swarm Computation To Study The Nanoscale Dg Mosfet-Based Circuits, Fayacl Djeffal, Toufik Bendib, Redha Benzid, Abdelhamid Benhaya Jan 2010

An Approach Based On Particle Swarm Computation To Study The Nanoscale Dg Mosfet-Based Circuits, Fayacl Djeffal, Toufik Bendib, Redha Benzid, Abdelhamid Benhaya

Turkish Journal of Electrical Engineering and Computer Sciences

The analytical modeling of nanoscale Double-Gate MOSFETs (DG) requires generally several necessary simplifying assumptions to lead to compact expressions of current-voltage characteristics for nanoscale CMOS circuits design. Further, progress in the development, design and optimization of nanoscale devices necessarily require new theory and modeling tools in order to improve the accuracy and the computational time of circuits' simulators. In this paper, we propose a new particle swarm strategy to study the nanoscale CMOS circuits. The latter is based on the 2-D numerical Non-Equilibrium Green's Function (NEGF) simulation and a new extended long channel DG MOSFET compact model. Good agreement between …


Securing Fuzzy Vault Schemes Through Biometric Hashing, Cengi̇z Örenci̇k, Thomas Brochmann Pedersen, Erkay Savaş, Mehmet Keski̇nöz Jan 2010

Securing Fuzzy Vault Schemes Through Biometric Hashing, Cengi̇z Örenci̇k, Thomas Brochmann Pedersen, Erkay Savaş, Mehmet Keski̇nöz

Turkish Journal of Electrical Engineering and Computer Sciences

The fuzzy vault scheme is a well-known technique to mitigate privacy, security, and usability related problems in biometric identification applications. The basic idea is to hide biometric data along with secret information amongst randomly selected chaff points during the enrollment process. Only the owner of the biometric data who presents correct biometrics can recover the secret and identify himself. Recent research, however, has shown that the scheme is vulnerable to certain types of attacks. The recently proposed ``correlation attack'', that allows linking two vaults of the same biometric, pose serious privacy risks that have not been sufficiently addressed. The primary …