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Articles 19111 - 19140 of 25675

Full-Text Articles in Engineering

Characterization Of A Total Power Radiometer, Murat Celep, Şenel Yaran, Yakup Gülmez, Ari̇f Dolma Jan 2012

Characterization Of A Total Power Radiometer, Murat Celep, Şenel Yaran, Yakup Gülmez, Ari̇f Dolma

Turkish Journal of Electrical Engineering and Computer Sciences

The performance parameters of a total power radiometer designed as a noise measurement system for the frequency range of 12-18 GHz were investigated. The total power radiometer included a low-noise radio frequency section, a narrow-band intermediate frequency section, an average power detector, and a symmetric microwave switch. The radiometer's stability versus time was 0.343 \times 10^{-5} mW/h and its stability against temperature fluctuation was 0.0035 mW/K. The temperature fluctuation of the radiometer was less than 4 mK. We proved that there was no need for active temperature control to obtain stable radiometer gain.

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Improvement Of Smart Card Based Password Authentication Scheme For Multiserver Environments, Zuowen Tan Jan 2012

Improvement Of Smart Card Based Password Authentication Scheme For Multiserver Environments, Zuowen Tan

Turkish Journal of Electrical Engineering and Computer Sciences

In multiserver (MS) environments, it is preferable for a remote user to login to different service provider servers by keying in the same password. Recently, Wang et al. proposed an improvement on the dynamic identity-based smart card authentication scheme of Liao and Wang for MS environments. Sandeep et al. improved the dynamic identity-based smart card authentication scheme of Hsiang et al. for MS architecture. However, we found that the schemes of Wang et al. and Sandeep et al. failed to provide service provider server authentication, perfect forward security, and login scalability. In addition, the scheme of Sandeep et al. was …

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An Algorithm For The Detection And Analysis Of Arud Meter In Diwan Poetry, Atakan Kurt, Mehmet Kara Jan 2012

An Algorithm For The Detection And Analysis Of Arud Meter In Diwan Poetry, Atakan Kurt, Mehmet Kara

Turkish Journal of Electrical Engineering and Computer Sciences

Diwan poetry is an important branch of classical Turkish literature (or Ottoman literature) that uses arud meter (wazn AR\footnote{Denotes an Arabic word.} or bahr AR, ölçü TR\footnote{Denotes a Turkish word.}). The teaching of classical poetry in high schools and in literature departments in universities requires an understanding of this meter. Arud is also used in Arabic, Persian, Urdu, and other eastern languages. Determining the arud meter of poems written in the Ottoman language (Osmanlıca TR) is a difficult and tedious task for those who study poetry. In this paper, we focus on the computerized analysis of arud meter. We present …

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Localized Power-Aware Routing With An Energy-Efficient Pipelined Wakeup Schedule For Wireless Sensor Networks, Taner Çevi̇k, Abdül Hali̇m Zai̇m, Derya Yiltaş Jan 2012

Localized Power-Aware Routing With An Energy-Efficient Pipelined Wakeup Schedule For Wireless Sensor Networks, Taner Çevi̇k, Abdül Hali̇m Zai̇m, Derya Yiltaş

Turkish Journal of Electrical Engineering and Computer Sciences

Depending on the evolutions in electronics, wireless sensor networks (WSNs) have been very popular in many areas of human life such as health, industry, and military. This popularity has drawn the attention of many researchers toward WSNs. WSNs are especially favorable in conditions in which it is physically difficult and dangerous for human beings to gather information. Therefore, the lifetime of those networks must be as long as possible, since it would also be infeasible to replace the energy-depleted sensors with new ones, as they may be deployed in such geographical areas that are difficult and dangerous for human beings …

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Analysis Of Orthogonal Matching Pursuit Based Subsurface Imaging For Compressive Ground Penetrating Radars, Mehmet Ali̇ Çağri Tuncer, Ali̇ Cafer Gürbüz Jan 2012

Analysis Of Orthogonal Matching Pursuit Based Subsurface Imaging For Compressive Ground Penetrating Radars, Mehmet Ali̇ Çağri Tuncer, Ali̇ Cafer Gürbüz

Turkish Journal of Electrical Engineering and Computer Sciences

It is shown that compressive sensing (CS) theory can be used for subsurface imaging in stepped frequency ground penetrating radars (GPR), resulting in robust sparse images, using fewer measurements. Although the data acquisition time is decreased by CS, the computational complexity of the minimization based imaging algorithm is too costly, which makes the algorithm useless, especially for extensive discretization or 3D imaging. In this paper, a greedy alternative, orthogonal matching pursuit (OMP) is used for imaging subsurface and its performance under various conditions is compared to CS imaging method. Results show that OMP could reconstruct sparse signals robustly as well …

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A Novel Structure To Enhance Magnetic Force And Velocity In Tubular Linear Reluctance Motor, Ali Mosallanejad, Abbas Shoulaie Jan 2012

A Novel Structure To Enhance Magnetic Force And Velocity In Tubular Linear Reluctance Motor, Ali Mosallanejad, Abbas Shoulaie

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel design for a tubular linear reluctance motor (TLRM) has been developed. This paper presents a novel structure to enhance magnetic force and velocity in a TLRM. The new structure is accomplished through some changes in a TLRM, which results in a step winding structure. Comparing the proposed motor and the typical motor performances, it is proven that the proposed motor has better performance. For dynamic modeling of the proposed TLRM and to obtain the motor output characteristics, the method used for inductance profile calculation is described. The performance improvements in the proposed motor are evaluated …

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Application Of The Posicast Control Method To Static Shunt Compensators, Amir Ghorbani, Siamak Masoudi, Arash Shabani Jan 2012

Application Of The Posicast Control Method To Static Shunt Compensators, Amir Ghorbani, Siamak Masoudi, Arash Shabani

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the Posicast control method is used for decreasing the reactive power oscillations of static shunt compensators. Shunt compensators such as the static synchronous compensator (STATCOM) and static VAR compensator (SVC) are considered to be FACTS devices. The applied control method decreases the amount of oscillations in the outputs of STATCOM and SVC considerably, with fast damping. In this paper, a PI controller is added to the model to decrease the sensitivity of the Posicast controller to the parameter variations and plant model mismatch. Simplicity and applicability are the main features of this controller. The model is simulated …

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Optimal Design Of Upfc-Based Damping Controller Using Imperialist Competitive Algorithm, Ali Ajami, Reza Gholizadeh Jan 2012

Optimal Design Of Upfc-Based Damping Controller Using Imperialist Competitive Algorithm, Ali Ajami, Reza Gholizadeh

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the optimal design of supplementary controller parameters of a unified power flow controller (UPFC) to damp low-frequency oscillations in a weakly connected system is investigated. The individual design of the UPFC controller, using the imperialist competitive algorithm (ICA) technique over a wide range of operating conditions, is discussed. The effectiveness and validity of the proposed controller on damping low-frequency oscillations is tested through a time-domain simulation and eigenvalue analysis under 4 loading conditions and a large disturbance. The simulation results, carried out using MATLAB/Simulink software, reveal that the tuned ICA-based UPFC controller has an excellent capability of …

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Broken Rotor Bar Fault Detection In Inverter-Fed Squirrel Cage Induction Motors Using Stator Current Analysis And Fuzzy Logic, Mehmet Akar, İlyas Çankaya Jan 2012

Broken Rotor Bar Fault Detection In Inverter-Fed Squirrel Cage Induction Motors Using Stator Current Analysis And Fuzzy Logic, Mehmet Akar, İlyas Çankaya

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the implementation of broken rotor bar fault detection in an inverter-fed induction motor using motor current signal analysis (MCSA) and prognosis with fuzzy logic. Recently, inverter-fed induction motors have become very popular because of their adjustable speed drive. They have been used in many vital control applications such as rolling mills, variable speed compressors, pumps, and fans. The condition monitoring of these motors can significantly reduce the cost of maintenance in the early detection of faults. In this study, MCSA is applied to an inverter-fed induction motor to detect broken rotor bar faults. The diagnosis of a …

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Fractional Pid Controllers Tuned By Evolutionary Algorithms For Robot Trajectory Control, Zafer Bi̇ngül, Oğuzhan Karahan Jan 2012

Fractional Pid Controllers Tuned By Evolutionary Algorithms For Robot Trajectory Control, Zafer Bi̇ngül, Oğuzhan Karahan

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this paper is to compare the performances of a fractional order proportional integral derivative (FOPID) controller tuned with evolutionary algorithms for robot trajectory control. In order to make this comparison, a 2-degrees-of-freedom planar robot was controlled by a FOPID controller tuned with particle swarm optimization (PSO) and a real coded genetic algorithm (GA). In order to see the effects of the cost functions on the optimum parameters of the FOPID controller, 3 different cost functions were used: the root mean squared error (MRSE), mean absolute error (MAE), and mean minimum fuel and absolute error (MMFAE). In order …

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Identification Of Linear Dynamic Systems Using The Artificial Bee Colony Algorithm, Özden Erçi̇n, Ramazan Çoban Jan 2012

Identification Of Linear Dynamic Systems Using The Artificial Bee Colony Algorithm, Özden Erçi̇n, Ramazan Çoban

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an investigation into the development of system identification using the artificial bee colony (ABC) algorithm. A system identification task can be formulated as an optimization problem where the objective is to obtain a model and a set of parameters that minimize the prediction error between the measured plant outputs and the model outputs. The most common existing system identification approaches, such as the recursive least squares method and autoregressive exogenous method, are substantially analytical and based on a mathematical derivation of the system's model. Evolutionary computation, which seems to be a very promising approach, is an alternative …

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Abstract Feature Extraction For Text Classification, Göksel Bi̇ri̇ci̇k, Banu Di̇ri̇, Ahmet Coşkun Sönmez Jan 2012

Abstract Feature Extraction For Text Classification, Göksel Bi̇ri̇ci̇k, Banu Di̇ri̇, Ahmet Coşkun Sönmez

Turkish Journal of Electrical Engineering and Computer Sciences

Feature selection and extraction are frequently used solutions to overcome the curse of dimensionality in text classification problems. We introduce an extraction method that summarizes the features of the document samples, where the new features aggregate information about how much evidence there is in a document, for each class. We project the high dimensional features of documents onto a new feature space having dimensions equal to the number of classes in order to form the abstract features. We test our method on 7 different text classification algorithms, with different classifier design approaches. We examine performances of the classifiers applied on …

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Pi And Pid Stabilization Of Neutral And Retarded Systems With Time Delay, Serdar Ethem Hamamci Jan 2012

Pi And Pid Stabilization Of Neutral And Retarded Systems With Time Delay, Serdar Ethem Hamamci

Turkish Journal of Electrical Engineering and Computer Sciences

Stabilization using fixed-order controllers is one of the key topics in control system design for the linear time-invariant (LTI) systems. In this paper, the stabilization of LTI neutral and retarded time-delay systems by means of PI and PID controllers is investigated in detail. The basic theme of the presented approach is to obtain a global stability region in the 2-dimensional (2-D) (k_p, k_i)-plane for the PI controller and in the 3-dimensional (3-D) (k_p, k_i, k_d)-space for the PID controllers. This region is formed by stability boundaries that are defined as the real root boundary, infinite root boundary, and complex root …

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An Implementation Of Modified Scatter Search Algorithm To Transmission Expansion Planning, Majid Zeinaddini Maymand, Masoud Rashidinejad, Hamid Khorasani, Mohsen Rahmani, Amin Mahmoudabadi Jan 2012

An Implementation Of Modified Scatter Search Algorithm To Transmission Expansion Planning, Majid Zeinaddini Maymand, Masoud Rashidinejad, Hamid Khorasani, Mohsen Rahmani, Amin Mahmoudabadi

Turkish Journal of Electrical Engineering and Computer Sciences

Transmission network expansion planning (TNEP) is one of the most important tasks in the field of power systems, especially in deregulated power system environments. TNEP is a nonlinear mixed integer programming problem that can be solved via hybrid heuristic algorithms. This paper presents a modified scatter search algorithm (MSSA) to reinforce the ordinary scatter search algorithm (SSA) to be equipped for handling large scale transmission expansion planning (TEP) problems. The proposed methodology is based on the SSA, incorporating some improved strategies so as to decrease the number of linear programming problems required to be solved iteratively. In this study, it …

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Dynamic Stability Enhancement Of A Multimachine Electric Power System Using Statcom, Hasan Fayazi Boroujeni, Reza Hemmati, Sayed Mojtaba Shirvani Boroujeni Jan 2012

Dynamic Stability Enhancement Of A Multimachine Electric Power System Using Statcom, Hasan Fayazi Boroujeni, Reza Hemmati, Sayed Mojtaba Shirvani Boroujeni

Turkish Journal of Electrical Engineering and Computer Sciences

With the expansion of electric power systems, the size and complexity of the network is increased. One of the most important drawbacks of network expansion is the reduction in the damping torque of the whole system. The lack of damping torque can lead to fluctuations and instability in the power system. With regard to this problem, power system stabilizers (PSSs) have been widely utilized to improve power system stability. However, due to some drawbacks of the conventional PSSs, the need for finding a better substitution still remains. Therefore, in this paper, the application of a static synchronous compensator (STATCOM) to …

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A Neural-Based Electromagnetic Inverse Scattering Approach To The Detection Of A Conducting Cylinder Coated With A Dielectric Material, Senem Makal, Ahmet Kizilay Jan 2012

A Neural-Based Electromagnetic Inverse Scattering Approach To The Detection Of A Conducting Cylinder Coated With A Dielectric Material, Senem Makal, Ahmet Kizilay

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a radial basis function neural network approach is applied for the estimation of the localization and the radius of a conducting cylinder with a circular cross-section coated with a dielectric material. A set of features, the radar cross-section (RCS) values, are derived from scattered fields, which are calculated using the surface equivalence principle and the method of moment. RCS values are obtained using 10 different scattering angles that are fed into the network. The outputs of the network are the location (x_0, y_0) and the radius (r_p) of the conducting cylinder. This is an application of the …

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Resolution Enhancement Of Video Sequences By Using Discrete Wavelet Transform And Illumination Compensation, Sara Izadpanahi, Çağri Özçinar, Gholamreza Anbarjafari, Hasan Demirel Jan 2012

Resolution Enhancement Of Video Sequences By Using Discrete Wavelet Transform And Illumination Compensation, Sara Izadpanahi, Çağri Özçinar, Gholamreza Anbarjafari, Hasan Demirel

Turkish Journal of Electrical Engineering and Computer Sciences

This research paper proposes a new technique for video resolution enhancement that employees an illumination compensation procedure before the registration process. After the illumination compensation process, the respective frames are registered using the Irani and Peleg technique. In parallel, the corresponding frame is decomposed into high-frequency (low-high, high-low, and high-high) and low-frequency (low-low) subbands using discrete wavelet transform (DWT). The high-frequency subbands are superresolved using bicubic interpolation. Afterwards, the interpolated high-frequency subbands and superresolved low-frequency subband obtained by registration are used to construct the high-resolution frame using inverse DWT. The superiority of the proposed resolution enhancement method over well-known video …

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Model Selection And Score Normalization For Text-Dependent Single Utterance Speaker Verification, Osman Büyük, Mustafa Levent Arslan Jan 2012

Model Selection And Score Normalization For Text-Dependent Single Utterance Speaker Verification, Osman Büyük, Mustafa Levent Arslan

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we investigate model selection and channel variability issues on a text-dependent single utterance (TDSU) speaker verification application. Due to the lack of an appropriate database for the task, a multichannel speaker recognition database, which consists of multiple recordings of a single Turkish utterance, is collected. The first set of experiments is devoted to model selection. Phonetic hidden Markov model (HMM)-based, sentence HMM-based, and Gaussian mixture model (GMM)-based methods are compared to find the most appropriate modeling approach for the target application. Based on the experimental results, the HMM-based methods outperform the GMM. The sentence HMM yields the …

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Hybrid Feature Selection For Text Classification, Serkan Günal Jan 2012

Hybrid Feature Selection For Text Classification, Serkan Günal

Turkish Journal of Electrical Engineering and Computer Sciences

Feature selection is vital in the field of pattern classification due to accuracy and processing time considerations. The selection of proper features is of greater importance when the initial feature set is considerably large. Text classification is a typical example of this situation, where the size of the initial feature set may reach to hundreds or even thousands. There are numerous research studies in the literature offering different feature selection strategies for text classification, mostly focused on filters. In spite of the extensive number of these studies, there is no significant work investigating the efficacy of a combination of features, …

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Using A Game-Based Learning Model As A New Teaching Strategy For Computer Engineering, Kristijan Kuk, Dragica Jovanovic, Dusan Jokanovic, Petar Spalevic, Marko Caric, Stefan Panic Jan 2012

Using A Game-Based Learning Model As A New Teaching Strategy For Computer Engineering, Kristijan Kuk, Dragica Jovanovic, Dusan Jokanovic, Petar Spalevic, Marko Caric, Stefan Panic

Turkish Journal of Electrical Engineering and Computer Sciences

Interactive multimedia simulations and computer game elements can be successfully combined in order to create new advanced educational resources for teaching today's generation of students. Such a learning environment, a game-based learning model (GBLm), has been designed as a research prototype. This paper describes one type of GBLm for computer engineering, which we have used in the subject of computer graphics for the teaching unit Z-buffer algorithm, in order to facilitate the learning process. The implementation of a GBLm for graphical algorithms (GBL4CAl) is presented in detail as a multimedia interactive learning module designed to motivate students by making learning …

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On The Degradation Of Ota-C--Based Cmos Low-Power Filter Circuits For Biomedical Instrumentation, Yasi̇n Özçelep, Ayten Kuntman, Hulusi̇ Hakan Kuntman Jan 2012

On The Degradation Of Ota-C--Based Cmos Low-Power Filter Circuits For Biomedical Instrumentation, Yasi̇n Özçelep, Ayten Kuntman, Hulusi̇ Hakan Kuntman

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, we propose a degraded transistor-based circuit degradation simulation method to investigate the degradation effect in complementary metal-oxide semiconductor (CMOS) biomedical devices. The method is demonstrated on an operational transconductance amplifier and capacitor (OTA-C)-based CMOS filter structure. First, we simulate the degradation of the symmetrical CMOS OTA by determining the degraded transistors in the structure. The simulation results are compared with the experimental results of our previous study. First- and second-order low-pass filter degradations are also simulated to demonstrate the accuracy of the proposed method. Finally, the degradation in the electroencephalogram band-pass filter and its effect on the …

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Adaptive Optimization Of Edca Parameters For Improved Qos In Multi-Media Applications, Alparslan Çi̇l, Mehmet Akar, Emi̇n Anarim Jan 2012

Adaptive Optimization Of Edca Parameters For Improved Qos In Multi-Media Applications, Alparslan Çi̇l, Mehmet Akar, Emi̇n Anarim

Turkish Journal of Electrical Engineering and Computer Sciences

IEEE 802.11e Enhanced Distributed Channel Access (EDCA) has been incorporated into the standard as an effective medium access mechanism in order to provide the desired QoS for multimedia applications such as VoIP and IPTV. This paper presents an adaptive optimization algorithm in EDCA which strives to provide improved QoS from both delay and throughput perspectives. As a first step towards this goal, a Markov model of the EDCA mechanism has been introduced, which is subsequently used to compute the estimates of throughput and delay. Based on the analytical model that is validated via real-time simulations in OPNET, a new algorithm …

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Hybrid Mpi+Upc Parallel Programming Paradigm On An Smp Cluster, Zeki̇ Bozkuş Jan 2012

Hybrid Mpi+Upc Parallel Programming Paradigm On An Smp Cluster, Zeki̇ Bozkuş

Turkish Journal of Electrical Engineering and Computer Sciences

The symmetric multiprocessing (SMP) cluster system, which consists of shared memory nodes with several multicore central processing units connected to a high-speed network to form a distributed memory system, is the most widely available hardware architecture for the high-performance computing community. Today, the Message Passing Interface (MPI) is the most widely used parallel programming paradigm for SMP clusters, in which the MPI provides programming both for an SMP node and among nodes simultaneously. However, Unified Parallel C (UPC) is an emerging alternative that supports the partitioned global address space model that can be again employed within and across the nodes …

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Improved Computerized Evaluation Of Abdominal Aortic Aneurysm, Semi̇h Utku, Hulusi̇ Baysal, Reyat Yilmaz, Aytaç Gülcü, Recep Alp Kut, Ahmet Yi̇ği̇t Göktay Jan 2012

Improved Computerized Evaluation Of Abdominal Aortic Aneurysm, Semi̇h Utku, Hulusi̇ Baysal, Reyat Yilmaz, Aytaç Gülcü, Recep Alp Kut, Ahmet Yi̇ği̇t Göktay

Turkish Journal of Electrical Engineering and Computer Sciences

Accurate measurements of arterial anatomy are emerging as the most important determinants of endovascular abdominal aneurysm repair. It is quite difficult to define and measure arterial anatomy features quantitatively due to the complex structure of the aneurysm and insufficient visual feedback. During decision making, to assist operators in diagnosing abdominal aortic aneurysms, a specialized preprocessing Abdominal Aortic Aneurysm Measurement and Evaluation Tool (AMET) was developed. AMET provides visual interfaces with broad measurement capabilities to generate a 3D model of the aorta for a better diagnosis and accurate stent selection. The accuracy and usability of the tool was tested with a …

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Openness, Intellectual Property And Standardization In The European Ict Sector, Carl Mair Jan 2012

Openness, Intellectual Property And Standardization In The European Ict Sector, Carl Mair

IP Theory

No abstract provided.

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Using Eye Tracking And Attention Maps In Computer Science Education, Austin Pernell Jan 2012

Using Eye Tracking And Attention Maps In Computer Science Education, Austin Pernell

Electronic Theses and Dissertations

Eye tracking has been used for many different areas of study where a user's eye movements are considered the most important information available. Before eye tracking was possible, the only way that information could be obtained was to ask the user where they looked and what caught their attention. Now, with the rise of eye tracking cameras, this data can be captured, stored, and processed in a meaningful way. These cameras aren't perfectly accurate however and there is still some interpretation that must be applied to more accurately represent the true gaze path of the user. This paper establishes some …

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Virtual Worlds And Conservational Channel Evolution And Pollutant Transport Systems (Concepts), Chenchutta Denaye Jackson Jan 2012

Virtual Worlds And Conservational Channel Evolution And Pollutant Transport Systems (Concepts), Chenchutta Denaye Jackson

Electronic Theses and Dissertations

Many models exist that predict channel morphology. Channel morphology is defined as the change in geometric parameters of a river. Channel morphology is affected by many factors. Some of these factors are caused either by man or by nature. To combat the adverse effects that man and nature may cause to a water system, scientists and engineers develop stream rehabilitation plans. Stream rehabilitation as defined by Shields et al., states that "restoration is the return from a degraded ecosystem back to a close approximation of its remaining natural potential" [Shields et al., 2003]. Engineers construct plans that will restore streams …

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On The Design Partitioning Of 3d Monolithic Circuits, Luke Maresca Jan 2012

On The Design Partitioning Of 3d Monolithic Circuits, Luke Maresca

Masters Theses

"Conventional three-dimensional integrated circuits (3D ICs) stack multiple dies vertically for higher integration density, shorter wirelength, smaller footprint, faster speed and lower power consumption. Due to the large through-silicon-via (TSV) sizes, 3D design partitioning is typically done at the architecture-level With the emerging monolithic 3D technology, TSVs can be made much smaller, which enables potential block-level partitioning. However, it is still unclear how much benefit can be obtained by block-level partitioning, which is affected by the number of tiers and the sizes of TSVs. In this thesis, an 8-bit ripple carry adder was used as an example to explore the …

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Real-Time Scheduling Of Parallel Tasks Under A General Dag Model, Abusayeed Saifullah, David Ferry, Chenyang Lu, Christopher Gill Jan 2012

Real-Time Scheduling Of Parallel Tasks Under A General Dag Model, Abusayeed Saifullah, David Ferry, Chenyang Lu, Christopher Gill

All Computer Science and Engineering Research

Due to their potential to deliver increased performance over single-core processors, multi-core processors have become mainstream in processor design. Computation-intensive real-time systems must exploit intra-task parallelism to take full advantage of multi-core processing. However, existing results in real-time scheduling of parallel tasks focus on restrictive task models such as the synchronous model where a task is a sequence of alternating parallel and sequential segments, and parallel segments have threads of execution that are of equal length. In this paper, we address a general model for deterministic parallel tasks, where a task is represented as a DAG with different nodes having …

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Accounting For Failures In Delay Analysis For Wirelesshart Networks , Abusayeed Saifullah, Paras Babu Tiwari, Bo Li, Chenyang Lu [email protected] Jan 2012

Accounting For Failures In Delay Analysis For Wirelesshart Networks , Abusayeed Saifullah, Paras Babu Tiwari, Bo Li, Chenyang Lu [email protected]

All Computer Science and Engineering Research

WirelessHART networks are gaining ground as a real-time communication infrastructure in industrial wireless control systems. Because wireless communication is often susceptible to transmission failures in industrial environments, it is essential to account for failures in the delay analysis for realtime flows between sensors and actuators in process control. WirelessHART networks handle transmission failures through retransmissions using dedicated and shared time slots through different paths in the routing graphs. While these mechanisms for handling transmission failures are critical for process control requiring reliable communication, they introduce substantial challenges to worst-case end-to-end delay analysis for real-time flows. This paper presents the first …

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