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

Computer Engineering Commons

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

23,523 Full-Text Articles 38,314 Authors 7,608,273 Downloads 262 Institutions

All Articles in Computer Engineering

Faceted Search

23,523 full-text articles. Page 920 of 927.

A Scalable Method For Solving High-Dimensional Continuous Pomdps Using Local Approximation, Tom Erez, William D. Smart 2010 Washington University in St Louis

A Scalable Method For Solving High-Dimensional Continuous Pomdps Using Local Approximation, Tom Erez, William D. Smart

All Computer Science and Engineering Research

Partially-Observable Markov Decision Processes (POMDPs) are typically solved by finding an approximate global solution to a corresponding belief-MDP. In this paper, we offer a new planning algorithm for POMDPs with continuous state, action and observation spaces. Since such domains have an inherent notion of locality, we can find an approximate solution using local optimization methods. We parameterize the belief distribution as a Gaussian mixture, and use the Extended Kalman Filter (EKF) to approximate the belief update. Since the EKF is a first-order filter, we can marginalize over the observations analytically. By using feedback control and state estimation during policy execution, …


Development Of A Remote Medical Image Browsing And Interaction System, Wei Ye 2010 Wright State University

Development Of A Remote Medical Image Browsing And Interaction System, Wei Ye

Browse all Theses and Dissertations

In this thesis a new capability - remote image browsing built upon our existing music telepresence platform is introduced. The implementation of this new image capability has two parts: one part is the local image viewing and the other part is distributed image-view interaction. Image viewing part is realized using the foundation of Linux GTK+ library. Most popular lossless and lossy image coding formats such as GIF, PNG, BMP and JPEG are supported currently. Image viewing part also provides several image operations such as: zoom in and zoom out, image information display and moreover users can select their own regions …


Authentication Of Biometric Features Using Texture Coding For Id Cards, Jonathan Blackledge, Eugene Coyle 2010 Technological University Dublin

Authentication Of Biometric Features Using Texture Coding For Id Cards, Jonathan Blackledge, Eugene Coyle

Conference papers

The use of image based information exchange has grown rapidly over the years in terms of both e-to-e image storage and transmission and in terms of maintaining paper documents in electronic form. Further, with the dramatic improvements in the quality of COTS (Commercial-Off-The-Shelf) printing and scanning devices, the ability to counterfeit electronic and printed documents has become a widespread problem. Consequently, there has been an increasing demand to develop digital watermarking techniques which can be applied to both electronic and printed images (and documents) that can be authenticated, prevent unauthorized copying of their content and, in the case of printed …


An Empirical Evaluation Of The Effectiveness Of Jml Assertions As Test Oracles, Kavir Shrestha 2010 University of Denver

An Empirical Evaluation Of The Effectiveness Of Jml Assertions As Test Oracles, Kavir Shrestha

Electronic Theses and Dissertations

Test oracles remain one of the least understood aspects of the modern testing process. An oracle is a mechanism used by software testers and software engineers for determining whether a test has passed or failed. One widely-supported approach to oracles is the use of runtime assertion checking during the testing activity. Method invariants,pre- and postconditions help detect bugs during runtime. While assertions are supported by virtually all programming environments, are used widely in practice, and are often assumed to be effective as test oracles, there are few empirical studies of their efficacy in this role. In this thesis, we present …


Challenges For Human, Social, Cultural, And Behavioral Modeling, S. K. Numrich, Andreas Tolk 2010 Old Dominion University

Challenges For Human, Social, Cultural, And Behavioral Modeling, S. K. Numrich, Andreas Tolk

Computational Modeling & Simulation Engineering Faculty Publications

Today's military focus has moved away from the force-on-force battlefield of the past century and into the domain of irregular warfare and its companion security, stability, transition and reconstruction missions. With that change in focus has come a need to examine the operational environment from a wider perspective, one that includes the whole range of human experiences and circumstances. As the set of factors and list of players expands, the need for reliable modeling and simulation increases, if for no other reason than to help the human decision maker make sense of this expanded decision space. However, to do this, …


E-Quality: Using Dimensional Index Values Towards Improving Classification Accuracy, Prashanth Devaram 2010 University of Texas at El Paso

E-Quality: Using Dimensional Index Values Towards Improving Classification Accuracy, Prashanth Devaram

Open Access Theses & Dissertations

E-quality is a process through which inspection of the process and quality of the part produced is done online resulting in the improvement of the process and reduction in the amount of time consumed for the overall process. Automated quality control involves using a methodology to classify the parts based on the dimensions of the features on a part. However, achieving 100% classification accuracy is not an easy task, especially in area of quality control where small differences in dimensions result in part fall into a different category. In this study, a novel approach for modifying the data before being …


Remote Sensing Applications Of Hf Skywave Radar: The Australian Experience, STUART ANDERSON 2010 TÜBİTAK

Remote Sensing Applications Of Hf Skywave Radar: The Australian Experience, Stuart Anderson

Turkish Journal of Electrical Engineering and Computer Sciences

Australia has conducted research into over-the-horizon radar (OTHR) for almost sixty years. Early programs focused exclusively on military capabilities, such as the detection of aircraft, missiles and ships, but in 1974 a team was formed to design a new OTHR for which a remote sensing mission was proposed. Oceanic wind mapping experiments in 1977-78 yielded promising results so remote sensing became a recognised mission assigned to the new radar, known as Jindalee Stage B. This capability was progressively expanded over the period 1982-87 to include mapping of wave height and other oceanographic variables. A real-time data link to the Australian …


Determination Of Autoregressive Model Orders For Seizure Detection, SERAP AYDIN 2010 TÜBİTAK

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 2010 TÜBİTAK

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 …


Improved Analytical Modulation Transfer Function For Image Intensified Charge Coupled Devices*, NEBİ GÜL, MURAT EFE 2010 TÜBİTAK

Improved Analytical Modulation Transfer Function For Image Intensified Charge Coupled Devices*, Nebi̇ Gül, Murat Efe

Turkish Journal of Electrical Engineering and Computer Sciences

The basic problem of simulation and modeling of Image Intensified Charge Coupled Device (ICCD) is the difference between the analytical Modulation Transfer Function (MTF) formulation used in the model and the experimentally obtained MTF. An investigation into the MTF of ICCD sub-components reveal that the MTF of the Image Intensifier Tube (IIT) is the main factor in this deviation. In this study, a regulation factor for the MTF of 3^{rd} generation IITs has been developed. A commonly used MTF formulation for IITs has been modified to include a regulation factor which has helped produce more precise MTF values for the …


P2p Collaborative Filtering With Privacy, CİHAN KALELİ, HÜSEYİN POLAT 2010 TÜBİTAK

P2p Collaborative Filtering With Privacy, Ci̇han Kaleli̇, Hüseyi̇n Polat

Turkish Journal of Electrical Engineering and Computer Sciences

With the evolution of the Internet and e-commerce, collaborative filtering (CF) and privacy-preserving collaborative filtering (PPCF) have become popular. The goal in CF is to generate predictions with decent accuracy, efficiently. The main issue in PPCF, however, is achieving such a goal while preserving users' privacy. Many implementations of CF and PPCF techniques proposed so far are centralized. In centralized systems, data is collected and stored by a central server for CF purposes. Centralized storage poses several hazards to users because the central server controls users' data. In this work, we investigate how to produce naïve Bayesian classifier (NBC)-based recommendations …


Comparison Of Daubechies Wavelets For Hurst Parameter Estimation, CEBRAİL ÇİFTLİKLİ, ALİ GEZER 2010 TÜBİTAK

Comparison Of Daubechies Wavelets For Hurst Parameter Estimation, Cebrai̇l Çi̇ftli̇kli̇, Ali̇ Gezer

Turkish Journal of Electrical Engineering and Computer Sciences

Time scale dependence on the working nature of wavelet analysis makes it a valuable tool for Hurst parameter estimation. Similar to other wavelet-based signal processing applications, the selection of a particular wavelet type and vanishing moment in wavelet based Hurst estimation is a challenging problem. In this paper, we investigate the best Daubechies wavelet in wavelet based Hurst estimation for an exact self similar process, fractional Gaussian noise and how Daubechies vanishing moment affects the Hurst estimation accuracy. Daubechies wavelets are preferred in analysis because increasing vanishing moment does not cause excessive increase of time support of Daubechies wavelets. Thus, …


Stochastic Stability Of The Discrete-Time Constrained Extended Kalman Filter, LEVENT ÖZBEK, ESİN KÖKSAL BABACAN, MURAT EFE 2010 TÜBİTAK

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.


K-Anonymity Based Framework For Privacy Preserving Data Collection In Wireless Sensor Networks, HAYRETDİN BAHŞİ, ALBERT LEVİ 2010 TÜBİTAK

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 …


A Power Quality Monitoring System Based On Matlab Server Pages, BÜLENT VURAL, ALİ KIZIL, MEHMET UZUNOĞLU 2010 TÜBİTAK

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 2010 TÜBİTAK

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.


Dual-Use Of Compact Hf Radars For The Detection Of Mid- And Large-Size Vessels, HUGH ROARTY, DON BARRICK, JOSH KOHUT, SCOTT GLENN 2010 TÜBİTAK

Dual-Use Of Compact Hf Radars For The Detection Of Mid- And Large-Size Vessels, Hugh Roarty, Don Barrick, Josh Kohut, Scott Glenn

Turkish Journal of Electrical Engineering and Computer Sciences

This paper describes the development of the SeaSonde High Frequency Radar system into a dual-use application for the mapping of ocean surface currents and detection of ships at sea. This development entailed the creation of a new radar waveform that would permit this dual-use as well as a detection algorithm to identify the ships in the radar spectra. The detection algorithm utilizes two methods for calculating a background signal level: an infinite impulse response (IIR) filter and a two-dimensional median filter. These two methods are employed simultaneously with multiple length averaging times to maximize the number of detections. The initial …


Modeling And Simulation Strategies In High Frequency Surface Wave Radars, LEVENT SEVGİ 2010 TÜBİTAK

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 2010 TÜBİTAK

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 …


Implementation Of Method For Operating Multiple High Frequency Surface Wave Radars On A Common Carrier Frequency, RYAN RIDDOLLS 2010 TÜBİTAK

Implementation Of Method For Operating Multiple High Frequency Surface Wave Radars On A Common Carrier Frequency, Ryan Riddolls

Turkish Journal of Electrical Engineering and Computer Sciences

The increasing use of High Frequency Surface Wave Radar (HFSWR) for the surveillance of coastal regions is faced with the problem of limited channel availability in the electromagnetic spectrum. Thus, there is a need for multiple radars to share a common frequency channel. Proof-of-concept work is presented here for a method to operate multiple radar systems on a common carrier frequency. A review is provided of an existing concept where a common waveform is modulated by tones varying by a few hertz across the different radars. The signals from the different radars are separated by either pulse-domain filtering or Doppler …


Digital Commons powered by bepress