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

Electrical and Computer Engineering Commons™

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

University of Texas at Arlington

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 571 - 600 of 656

Full-Text Articles in Electrical and Computer Engineering

Improved Refinement Coefficients' Coding In Scalable H.264, Rahul Panchal Apr 2007

Improved Refinement Coefficients' Coding In Scalable H.264, Rahul Panchal

Electrical Engineering Theses - Archive

This thesis proposes to replace the adaptation used to select VLC table for coding of the refinement coefficient by signaling to the decoder which table should be used for which macroblock type (Inter or Intra) in scalable H.264. This part of the proposal aims at reducing decoder complexity and ensuring proper table selection when both macroblock types are present within one slice. The contribution further proposes to extend the method used in SVC to increase coding efficiency of CABAC refinement coefficient coding to "VLC" refinement coefficients coding. All the coding tools are integrated into JSVM_7_10 and the performance is tested. …

Go to article

Multiplexing H.264 Video With Aac Audio Bit Streams, Demultiplexing And Achieving Lip Synchronization During Playback, Harishankar Murugan Apr 2007

Multiplexing H.264 Video With Aac Audio Bit Streams, Demultiplexing And Achieving Lip Synchronization During Playback, Harishankar Murugan

Electrical Engineering Theses - Archive

H.264, MPEG-4 part-10 or AVC [5], is the latest digital video codec standard which has proven to be superior than any early standards in terms of compression ratio, quality, bit rates and error resilience. However, the standard just defines a video codec and has no mention of any audio compression. In order to have a meaningful delivery of the video to the end user, we need to associate an audio stream along with it. AAC (advanced audio coding) [1] is the latest digital audio codec standard defined in MPEG-2 and later in MPEG-4 with few changes. The audio quality of …

Go to article

Transcoding From H264 Bitstream To Mpeg-2 Bitstream, Sreejana Sharma Apr 2007

Transcoding From H264 Bitstream To Mpeg-2 Bitstream, Sreejana Sharma

Electrical Engineering Theses - Archive

H.264/AVC was recently developed by the JVT (Joint Video Team). This new standard fulfills significant coding efficiency, simple syntax specifications and seamless integration of video coding into all current protocols and multiplex architectures. The H.264 specification represents a significant advancement in the field of video coding technology by providing MPEG-2 comparable video quality at an average of half the required bandwidth. Since widespread use of H.264 is anticipated, many legacy systems including all Digital TVs and home receivers use MPEG-2. This leads to the need for an efficient architecture that significantly employs the lower cost of H.264 video and does …

Go to article

A Piecewise Linear Classifier, Abdul Aziz Abdurrab Apr 2007

A Piecewise Linear Classifier, Abdul Aziz Abdurrab

Electrical Engineering Theses - Archive

A piecewise linear network is discussed which classifies N-dimensional input vectors. The network uses a distance measure to assign incoming input vectors to an appropriate cluster. Each cluster has a linear classifier for generating class discriminants. A training algorithm is described for generating the clusters and discriminants. A pruning algorithm is also described. The algorithm is applied after the network has grown completely, i.e, it has achieved the maximum number of clusters. The pruning algorithm eliminates the least important clusters, one at a time, leading to a more compact network. Theorems are given which relate the network's performance to that …

Go to article

A Functional Link Network Using Ordered Basis Functions, Saurabh Sureka Apr 2007

A Functional Link Network Using Ordered Basis Functions, Saurabh Sureka

Electrical Engineering Theses - Archive

A new function approximation and classification network based on Functional Link Network (FLN) with orthonormal Polynomial Basis Functions (PBF) is presented. By using an iterative Gram-Schmidt procedure, the PBF's are orthonormalized, ordered and selected based on their contribution to minimize the Mean Square Error (MSE). Linearly dependent and less useful PBF are detected and eliminated at an early stage thereby improving the approximation capabilities and reducing the possibility of combinatorial explosion. The number of passes through the data during network training is minimized through the use of correlations. A one-pass method is used for validation and network sizing. Equivalent function …

Go to article

Rf Sputtered Sixge1-X And Sixge1-Xoy Thin Films For Uncooled Infrared Detectors, Mukti M. Rana Mar 2007

Rf Sputtered Sixge1-X And Sixge1-Xoy Thin Films For Uncooled Infrared Detectors, Mukti M. Rana

Electrical Engineering Dissertations - Archive

The objective of this work is to find a suitable combination of radio frequency (RF) sputtered SixGe1-x and SixGe1-xOy thin films for uncooled infrared detection. Thus, fabricating and characterizing microbolometers with SixGe1-x and SixGe1-xOy thin films as the sensing material are the ultimate goal of this work. Thin films of SixGe1-x and SixGe1-xOy were deposited by RF magnetron sputtering at room temperature from a single target of SixGe1-x in Ar or Ar : O2 environment. The silicon and oxygen concentrations were varied in a parametric investigation of the dependence of the electrical and optical characteristics of the thin films on …

Go to article

Dynamic Voltage Restorer For Sensitive Equipment, Yea Zong Kuo Mar 2007

Dynamic Voltage Restorer For Sensitive Equipment, Yea Zong Kuo

Electrical Engineering Dissertations - Archive

Voltage sags are considered to be the most frequent type of disturbances in the field based on recent power disturbances studies. Their impact on sensitive loads is severe. The impact ranges from load disruptions to substantial economic losses. Despite the technical advances in electronics, there are still some pieces of equipment that are so sensitive that they are unable to withstand voltage sags. An example is the equipment in semiconductor manufacturing. As a result, there is still a search for different ways to manage voltage sags. There are many different methods to mitigate voltage sags, but a CUstom Power Supply …

Go to article

Issues In Front-End Engineering Of Cmos Nanoelectronics, Xiaolong Yang Mar 2007

Issues In Front-End Engineering Of Cmos Nanoelectronics, Xiaolong Yang

Electrical Engineering Dissertations - Archive

Several issues exist in current CMOS front-end engineering such as interfacial layer formation at high-k/Si interface, high metal/Si contact resistance in source and drain regions, and absence of a quantitative model for silicon-germanium alloy growth. In this dissertation, monolayer Se passivation is employed to create a Si (100) surface free of dangling bonds. Since dangling bonds are the origins of surface reaction sites and surface states, interfacial layer formation at high-k/Si interface can be suppressed and metal/Si contact resistance can be lowered by Se passivation. Firstly, results on interface engineering between HfO2 and n-type Si (100) with Se passivation are …

Go to article

Simulation And Development Of Nanoscale Deposition Techniques Using Kinetic Monte Carlo, Corey Clark Jan 2007

Simulation And Development Of Nanoscale Deposition Techniques Using Kinetic Monte Carlo, Corey Clark

Electrical Engineering Dissertations - Archive

Modeling of deposition processes has become of extreme importance due to the small scale of devices and features as well as the reduction of time to market required by industry. Current modeling procedures have focused on individual aspects of growth as well as made assumptions that cause simplification of the problem to the point the models usefulness is limited. The Kinetic Monte Carlo (KMC) model developed in this work combines rate transitions that have been commonly found in KMC simulation along with energy density equations that help explain the transitions and formations of island in alloy deposition. Specifically the model …

Go to article

Localization Algorithms For Passive Targets In Radar Networks, Kartik Trasi Dec 2006

Localization Algorithms For Passive Targets In Radar Networks, Kartik Trasi

Electrical Engineering Theses - Archive

In this study, we propose an improved, robust algorithm for passive targets in radar networks. The main objective of this work is to improve the localization accuracy of the algorithm based on signal properties in combination with robust graphical techniques. We present a numerical approach and an experimental validation of the modified algorithm.

Go to article

Observer Synthesis For Linear/Nonlinear Dynamical Systems Subject To Measurement Delays, Praveen C. Muralidhar Dec 2006

Observer Synthesis For Linear/Nonlinear Dynamical Systems Subject To Measurement Delays, Praveen C. Muralidhar

Electrical Engineering Theses - Archive

In this research, problems associated with communication delays on the stability of formation of a group of unmanned vehicles is examined and solution to this problem is proposed. Ideally, it is required that the information transfer between the vehicles participating in a cooperative task be available immediately. But, in reality, there is always a delay between the instants at which the information is transmitted by one vehicle and the instant at which it is received by the other vehicles in the formation. A state observer is used to estimate the time delayed signal. The observer consists of two dynamic systems …

Go to article

Generation Planning And Market Operation Strategies In The Southwest Power Pool Energy Imbalance Service Market, Kittipong Methaprayoon Dec 2006

Generation Planning And Market Operation Strategies In The Southwest Power Pool Energy Imbalance Service Market, Kittipong Methaprayoon

Electrical Engineering Dissertations - Archive

The transition of the Southwest Power Pool (SPP) from its traditional operation under tariff towards the new market environment has significant impact on the utilities in the SPP footprint, both in terms of planning and operations. The new market regulation creates the need for the utilities to reassess their planning strategy, primarily to ensure that operational decisions conform to the new market rules while remain profitable under the new operating regime. The utilities are referred to as Market Participants (MP) under the new market scheme. The new market environment will expose the MPs to a large amount of information with …

Go to article

Fiber Optic Scanner Using Electromagnetic Actuation With Different Ferromagnetic Materials, Pratibha C. Phuyal Dec 2006

Fiber Optic Scanner Using Electromagnetic Actuation With Different Ferromagnetic Materials, Pratibha C. Phuyal

Electrical Engineering Theses - Archive

A fiber optic scanner capable of scanning medical imaging actuated by an external magnetic field is designed and characterized using different magnetized and non magnetized ferromagnetic materials. Cobalt, Iron, Nickel, and Samarium Cobalt powders were used before and after magnetization to perform the actuation. Plastic optical fiber and a silica optical fiber are coated with 70 % enamel paint with 30 % different ferromagnetic materials mixed using brush. Due the low Young's Modulus, the plastic optical fiber could not actuate like silica optical fiber. Therefore, the silica fiber was used to conduct the experiments. The static and dynamic measurements were …

Go to article

Neural Network Solution For Fixed-Final Time Optimal Control Of Nonlinear Systems, Tao Cheng Dec 2006

Neural Network Solution For Fixed-Final Time Optimal Control Of Nonlinear Systems, Tao Cheng

Electrical Engineering Dissertations - Archive

In this research, practical methods for the design of H2 and H-Infinity optimal state feedback controllers for unconstrained and constrained input systems are proposed. The dynamic programming principle is used along with special quasi-norms to derive the structure of both the saturated and optimal controllers in feedback strategy form. The resulting Hamilton-Jacobi-Bellman (HJB) and Hamilton-Jacobi-Isaacs (HJI) equations are derived respectively. Neural networks are used along with the least-squares method to solve the Hamilton-Jacobi differential equations in the H2 case, and the cost and disturbance in the H-Infinity case. The result is a neural network unconstrained or constrained feedback controller that …

Go to article

Performance Analysis And Design Of Space-Time Codes, Chen Liao Dec 2006

Performance Analysis And Design Of Space-Time Codes, Chen Liao

Electrical Engineering Dissertations - Archive

In this dissertation, performance and design of space-time codes have been studied. The main objective of this dissertation has been to improve the performance of space-time codes. This dissertation covers a wide range of topics in space-time codes. It involves theoretical analysis, design, and implementation for space-time trellis codes, space-time turbo codes, and orthogonal space-time codes. We begin with the study of performance analysis of upper bound of pair-wise error probability (PEP) and exact PEP. The exact PEP is derived using a straightforward method. The exact PEP provides a better understanding of the performance behavior to the other range of …

Go to article

Dynamic Stability Analysis Of Large-Scale Power Systems Using A Fast Investigation Method, Ming-Tse Kuo Dec 2006

Dynamic Stability Analysis Of Large-Scale Power Systems Using A Fast Investigation Method, Ming-Tse Kuo

Electrical Engineering Dissertations - Archive

Following power market deregulation and the proposed standard market design, the activities of cross boundary power transactions are increased significantly. Traditional company based stability analysis can not satisfy today's operating environment. However, simulating the entire interconnection power system may exceed the capacity of existing commercial stability analysis software. Fortunately, most of the stability problems are started from the local level. One will be able to avoid most of the system wide stability issues by mitigating the problems in the early stage. Based on eigenvector decompositions of the Jacobian, this dissertation proposes a new algorithm for performing the dynamic stability problem …

Go to article

Fabrication, Characterization And Hall Mobility Analysis Of Mos Devices With Low-K And High-K Dielectric Materials, Rakshit Agrawal Dec 2006

Fabrication, Characterization And Hall Mobility Analysis Of Mos Devices With Low-K And High-K Dielectric Materials, Rakshit Agrawal

Electrical Engineering Theses - Archive

Scaling of MOSFETS has led to leakage current problems in SiO2 dielectric based MOSFETS. This has led to the introduction of high-k dielectric materials which can afford greater physical thickness and achieve the same capacitance with lesser equivalent oxide thickness. But the high-k devices have certain limitations like channel mobility degradation. Mobility degradation in high-k MISFETS is discussed in this work using Hall measurements. The MOS devices were fabricated with SiO2 and HfSiO, on p-type silicon substrate. The fabrication process flow used for both type of MOS devices is explained. Characterization and analysis was performed for the determination of various …

Go to article

Arribot- An Enabler For Studying Mobile Wireless Sensor Networks, Jaymala Suresh Ghadigaonkar Dec 2006

Arribot- An Enabler For Studying Mobile Wireless Sensor Networks, Jaymala Suresh Ghadigaonkar

Electrical Engineering Theses - Archive

The objective of this thesis is to structure a mobile wireless sensor network using low cost, custom made robotic platforms. Over the years, several projects have proved that the performance of a static wireless sensor network (WSN) is greatly enhanced by using mobile WSN for applications like adaptive exploration or in search and rescue missions where the network topology changes with changes in the environment. A low cost, mobile wireless sensor node known as the ARRI BOT has been designed to contribute along with other robotic platforms in structuring an ingenious mobile wireless sensor network (MSWN). The ARRI BOT has …

Go to article

Physical Layer And Application Layer Issues Of Wireless Sensor Networks, Lingming Wang Dec 2006

Physical Layer And Application Layer Issues Of Wireless Sensor Networks, Lingming Wang

Electrical Engineering Dissertations - Archive

The potential for collaborative, robust networks of wireless sensors has attracted a great deal of research attention. For the most part, this is due to the compelling applications that wireless sensor networks will enable. Location sensing, environmental observation and surveillance, medical monitoring and a lot other applications are all gaining interest. However, wireless sensor network poses a large number of challenges. Among all, one of the most important challenges is design sensor networks that have long network lifetime, which will become especially difficult due to the energy-constrained nature of the sensor nodes. In this thesis, we focus on physical and …

Go to article

Applications Of Ultra Wideband, Liang-An Wei Nov 2006

Applications Of Ultra Wideband, Liang-An Wei

Electrical Engineering Theses - Archive

Ultra wideband (UWB) is a new wireless communication system. It utilizes transmission signal at wide bandwidths. With wider bandwidth, it can provide for new useful applications. The first chapter in this thesis discusses the features and advantages of the UWB. Chapters 2 and 3 present two proposed UWB applications. Chapter 2 presents the use of UWB in shipping containers. The security of shipping containers is an urgent issue for globally. UWB can provide a solution to secure containers. Our goal is to develop a system to enhance the transmission signals. In comparison with other system designs, our waveguide approach satisfies …

Go to article

Simulation And E-Beam Patterning Of Single Electron Transistor, Karan Deep Nov 2006

Simulation And E-Beam Patterning Of Single Electron Transistor, Karan Deep

Electrical Engineering Theses - Archive

Electron beam lithography is gaining widespread use as semiconductor industry. Current optical lithography techniques are limited to resolution of few hundreds of nanometers and suffer from diffraction problems. The focus of this thesis is to pattern single electron transistors (SET) using electron beam lithography on silicon and silicon on insulator (SOI) substrate which can be further processed to form working SET device. We used different types of e-beam resists like UVN 30, PMMA and HSQ to define source, drain and island for SET. We demonstrated the use of RIE and Deep RIE to etch silicon by using resist as etch …

Go to article

Phase Locked Loop For Radiation Hardened Environment, Jer-Fu Dennis Wu Nov 2006

Phase Locked Loop For Radiation Hardened Environment, Jer-Fu Dennis Wu

Electrical Engineering Theses - Archive

This thesis describes a Phase Locked Loop (PLL) design for operation within a radiation environment. Specific design architecture and techniques were implemented to help mitigate radiation effects that degrade PLL performance. This thesis presents several elements of a rad-hard PLL that were developed to solve this challenge, such as a very wideband coupling coefficient LC VCO that has a much higher frequency tuning range than conventional varactor based LC VCOs. The PLL consists a Phase and Frequency Detector (PFD), a rail to rail charge pump, a loop filter, the quadrature LC tank Voltage Controlled Oscillator (VCO), a Current Mode Logic …

Go to article

Models And Algorithms To Determine Cerebral Activation Using Near Infrared Spectroscopy, Monica Suresh Allen Nov 2006

Models And Algorithms To Determine Cerebral Activation Using Near Infrared Spectroscopy, Monica Suresh Allen

Electrical Engineering Dissertations - Archive

The specific aims of this dissertation were to develop: (1) Correlations between experimental protocols and oxygenated, deoxygenated, and total hemoglobin concentrations in the brain (2) Mathematical models to associate blood flow and oxygen consumption rate of the activated brain regions with measured hemodynamic changes (3) A phantom that models brain vasculature compliance to validate developed mathematical models in a controlled setup. The primary imaging modality used in the experimentation phase of this research was near infrared spectroscopy. Previously published multimodality measurements were also used to validate the mathematical models. The single compartment Windkessel model was extended to describe flow-volume dynamics …

Go to article

Monitoring And Fault Diagnosis Of Multiconverter Power Electronic Systems, Ranjit Jayabalan Sep 2006

Monitoring And Fault Diagnosis Of Multiconverter Power Electronic Systems, Ranjit Jayabalan

Electrical Engineering Dissertations - Archive

Over the recent years the electric loads in automobiles have increased considerably due to advancements in high-power semiconductor based converters. However, with increasing electrical and electrically driven loads, there have been increasing concerns on system reliability. Faults occurring in such application specific solid state converters can lead to fatal consequences as compared to their mechanical counter parts. Thus, it is vital to identify faults in such systems to develop necessary safety techniques and methodologies. Detailed analysis of faults processes has indicated the need to act quickly following a device failure to prevent propagation of faults that may lead to catastrophic …

Go to article

Optimization Of Hydrogen Filling Station, Vishal Bhan Aug 2006

Optimization Of Hydrogen Filling Station, Vishal Bhan

Electrical Engineering Theses - Archive

After experiencing the price hikes in the fuel and electricity, renewable energy is considered as one of the most attractive alternatives for future utility industry. Also, Hydrogen via renewable energy is of interest due to the environmental concern when compared with traditional fossil fuels. The Energy Bill of 2005 has included an authorization of $3.7 billion for hydrogen and fuel cell research and development. Further, hydrogen fuel cell vehicles (FCVs) are currently in the pre-production stage of development and the infrastructure needs to support them. Hence to overcome issues like price hike, exhaustion of crude oil and to gain appreciation …

Go to article

Emulation Of Asic Based Network Processor On A Fpga Platform, Sharada Vajja Aug 2006

Emulation Of Asic Based Network Processor On A Fpga Platform, Sharada Vajja

Electrical Engineering Theses - Archive

ABSTRACT Exponential increase of device sizes and complexity of ASICs mandate the need for design verification to meet timing specifications and functionality requirements. Verification techniques are broadly implemented in three categories viz., simulation, verification using commercial emulators and FPGA based prototyping. An Intel architecture based network processor, to be taped out in the near future, is being emulated on FPGA based platform. The basic blocks of the Network Processor, for instance, the Memory Controller Hub and I/O controller Hub were synthesized to be configured on FPGAs. The work involved synthesizing the design, partitioning it on multiple FPGAs and pin multiplexing …

Go to article

Mitigation Of Window Effects In Inverse Synthetic Aperture Radar (Isar) Imagery Using Multi-Resolution Technique, Suman Kumar Gunnala Aug 2006

Mitigation Of Window Effects In Inverse Synthetic Aperture Radar (Isar) Imagery Using Multi-Resolution Technique, Suman Kumar Gunnala

Electrical Engineering Theses - Archive

A method using Multi-Resolution technique for window effect mitigation in ISAR imagery, which occurs due to finite extent data, is presented in this work. Proposed method is supported with quantitative measure using both Structural Similarity (SSIM) and Mean Square Error (MSE). In addition, above index measures were used to determine the best choice of wavelet basis for window effect mitigation. Complete angular window and partial angular window are used as two cases to demonstrate the validation of above contributions. Scattering measurements of different test sets were done to validate the approach. Results which include reconstructed images and quantitative index measures …

Go to article

Hourly Weather Forecast Analysis, Sothaya Rasmidatta Aug 2006

Hourly Weather Forecast Analysis, Sothaya Rasmidatta

Electrical Engineering Theses - Archive

Today, internet becomes one of the most important resources for useful information. However, since the authentic of the information is difficult to verify, one also has to take precaution when getting information from the internet. Utility companies need to forecast their load for unit commitment scheduling and system planning. The traditional approach for neural network forecasting relies on the temperature forecasting information from a single source. The customer loads are closely correlated with the temperature. Therefore, the accuracy of the load forecasting is affected by the temperature forecasting errors. The objective of this thesis is to reduce the temperature forecasting …

Go to article

Recirculating Loop Testbed For All Optical 2r Regeneration, Pallavi Govind Patki Aug 2006

Recirculating Loop Testbed For All Optical 2r Regeneration, Pallavi Govind Patki

Electrical Engineering Theses - Archive

This Master's thesis deals with building a recirculating loop testbed intended for proof-of-principle demonstration of multichannel all-optical 2R regenerator proposed in [1]. The proposed multichannel 2R regeneration scheme uses multiple highly-nonlinear-fiber (HNLF) sections separated by dispersion-compensating periodic-group-delay devices (PGDDs). The high cost and limited availability of these devices restrict us to working with just one PGDD, instead of 16 required by the scheme. Thus, for the proof-of-principle demonstration of the regenerator we have to put a single PGDD and a piece of HNLF into a recirculating loop through which light will circulate for required number of times. In this thesis, …

Go to article

Rf Mems And Integrated Manufacturing For Miniaturized Millimeter-Wave Systems, Ying Cai Aug 2006

Rf Mems And Integrated Manufacturing For Miniaturized Millimeter-Wave Systems, Ying Cai

Electrical Engineering Dissertations - Archive

Recently millimeter-wave systems have attracted more attentions in applications owing to their short wavelengths, high resolutions, broad bandwidths and high environmental tolerance. However, the great challenges of high fabrication and assembly costs, bulky volume, and heavy weight of millimeter-wave systems call for new integrated manufacturing techniques and novel architectures. The micro hot embossing technique integrated with other microfabrication techniques could address these challenges. In this dissertation, the micro plastic hot embossing technique was presented for the fabrication of miniaturized millimeter-wave systems. The micro hot embossing on plastic materials demonstrated its advantages on significant costs, volume, and weight reduction, while maintaining …

Go to article

First Prev Next Last