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Full-Text Articles in Engineering
Fabrication, Characterization And Hall Mobility Analysis Of Mos Devices With Low-K And High-K Dielectric Materials, Rakshit Agrawal
Fabrication, Characterization And Hall Mobility Analysis Of Mos Devices With Low-K And High-K Dielectric Materials, Rakshit Agrawal
Electrical Engineering Theses
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 …
Fiber Optic Scanner Using Electromagnetic Actuation With Different Ferromagnetic Materials, Pratibha C. Phuyal
Fiber Optic Scanner Using Electromagnetic Actuation With Different Ferromagnetic Materials, Pratibha C. Phuyal
Electrical Engineering Theses
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 …
Arribot- An Enabler For Studying Mobile Wireless Sensor Networks, Jaymala Suresh Ghadigaonkar
Arribot- An Enabler For Studying Mobile Wireless Sensor Networks, Jaymala Suresh Ghadigaonkar
Electrical Engineering Theses
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 …
Localization Algorithms For Passive Targets In Radar Networks, Kartik Trasi
Localization Algorithms For Passive Targets In Radar Networks, Kartik Trasi
Electrical Engineering Theses
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.
Observer Synthesis For Linear/Nonlinear Dynamical Systems Subject To Measurement Delays, Praveen C. Muralidhar
Observer Synthesis For Linear/Nonlinear Dynamical Systems Subject To Measurement Delays, Praveen C. Muralidhar
Electrical Engineering Theses
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 …
Applications Of Ultra Wideband, Liang-An Wei
Applications Of Ultra Wideband, Liang-An Wei
Electrical Engineering Theses
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 …
Simulation And E-Beam Patterning Of Single Electron Transistor, Karan Deep
Simulation And E-Beam Patterning Of Single Electron Transistor, Karan Deep
Electrical Engineering Theses
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 …
Phase Locked Loop For Radiation Hardened Environment, Jer-Fu Dennis Wu
Phase Locked Loop For Radiation Hardened Environment, Jer-Fu Dennis Wu
Electrical Engineering Theses
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 …
Nonlinear Control Of Microelectromechanical Systems (Mems) Devices, Kwadwo Osei Owusu
Nonlinear Control Of Microelectromechanical Systems (Mems) Devices, Kwadwo Osei Owusu
Electrical Engineering Theses
Different actuation principles have been developed for MEMS but electrostatic actuators are the most common. A significant drawback in the use of electrostatic actuators for some applications is their nonlinear voltage to position characteristics. Analog operation of these devices requires the use of feedback to stabilize and linearize them. Controlling and optimizing the operation of electrostatic controllers using feedback requires the establishment of the complete and accurate dynamical model of the device. In this thesis, we show how an optical switch driven by a MEMS electrostatic comb drive is controlled to guarantee its performance, stability and reliability for use in …
3d Interconnects For Die And Wafer Stacks, Rachita Dewan
3d Interconnects For Die And Wafer Stacks, Rachita Dewan
Electrical Engineering Theses
3D integration results from the ever demanding trend towards smaller and lower-profile, lighter and lower cost packaged devices requires further package miniaturization. With the present System-on-chip (SOC) technology reaching its limitation in terms of functionality and cost, effort are being concentrated on exploring the third dimension, i.e. 3D integration. It provides a volumetric packaging solution for higher integration and performance and results in size and weight reduction. Approaches to achieve 3D integration are die and wafer stacking. A key technology to realize the potential of stacking is implementation of vertical electrical interconnects between die and wafer stacks. This thesis discusses …
The Design And Analysis Of Optical Scanners For Optical Coherence Tomography, Naresh Dhaubanjar
The Design And Analysis Of Optical Scanners For Optical Coherence Tomography, Naresh Dhaubanjar
Electrical Engineering Theses
A miniature fiber optic scanner capable of two-dimensional scanning for medical imaging is designed and developed. The scanner is actuated externally using an electromagnet. Nickel gel, a soft ferromagnetic material, is coated on the optical fiber. The performance of the scanner is characterized. Finite element analysis is performed to validate the theoretical and experimental results. A design and analysis of a cantilever type electrostatic zipping actuator and a bidirectional vertical thermal actuator are presented. The actuation principle, lumped modeling analysis, experimental results, and finite element analysis of both actuators are presented. The actuators are characterized statically and dynamically using the …
Modeling And Performance Evaluation Of A Power Electronic-Based Controlled Fuel Cell System, Yashar Ehsan Kenarangui
Modeling And Performance Evaluation Of A Power Electronic-Based Controlled Fuel Cell System, Yashar Ehsan Kenarangui
Electrical Engineering Theses
In fuel cell applications, design of an appropriate controller and selection of an Ultra-Capacitor require a suitable model of fuel-cell-systems that can adequately represent the significant characteristics of the system. Such a model, using lumped circuit elements, was developed in this thesis via a simple method without requiring fuel cell design parameters. To validate the model, simulation results from the model were compared against the results from experimental setups and satisfactory results were obtained. Later, this model was used in order to design a controller that meets the control objectives, namely, regulation of output voltage and attenuation of load current …
Optimization Of Hydrogen Filling Station, Vishal Bhan
Optimization Of Hydrogen Filling Station, Vishal Bhan
Electrical Engineering Theses
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 …
Emulation Of Asic Based Network Processor On A Fpga Platform, Sharada Vajja
Emulation Of Asic Based Network Processor On A Fpga Platform, Sharada Vajja
Electrical Engineering Theses
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 …
Mitigation Of Window Effects In Inverse Synthetic Aperture Radar (Isar) Imagery Using Multi-Resolution Technique, Suman Kumar Gunnala
Mitigation Of Window Effects In Inverse Synthetic Aperture Radar (Isar) Imagery Using Multi-Resolution Technique, Suman Kumar Gunnala
Electrical Engineering Theses
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 …
Hourly Weather Forecast Analysis, Sothaya Rasmidatta
Hourly Weather Forecast Analysis, Sothaya Rasmidatta
Electrical Engineering Theses
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 …
Recirculating Loop Testbed For All Optical 2r Regeneration, Pallavi Govind Patki
Recirculating Loop Testbed For All Optical 2r Regeneration, Pallavi Govind Patki
Electrical Engineering Theses
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, …
An Emission Model For Lunar Regolith Surfaces Based On Matrix Doubling Method, Darshan Shrestha
An Emission Model For Lunar Regolith Surfaces Based On Matrix Doubling Method, Darshan Shrestha
Electrical Engineering Theses
An emission model based on Matrix Doubling Method is implemented for the calculation of emission signatures from the lunar regolith surfaces. The matrix doubling method is used to solve the radiative transfer equations which encompass the volume and surface scattering properties of the medium. The layer and surface are characterized by their corresponding phase matrices which contain adequate information on how the amplitude, phase and polarization of the incident Stokes vector change on being incident in that medium. Emissivity signatures are calculated by solving the transfer equations using matrix doubling method and taking these phase matrices as "boundary conditions". The …
Analysis Of Electromagnetic Field In A Switched Reluctance Machine From An Energy Conversion Perspective, Wei Jiang
Electrical Engineering Theses
With the recent advancement in power electronics and digital signal processors, switched reluctance machine (SRM) attracts more attention in high speed and harsh environment applications due to its rugged and robust structure. Despite considerable progress in the development of power electronics based control of the SRM, relatively small changes in the magnetic design has been observed. A physically insightful analysis of the electromechanical energy conversion process, origins and spatial distribution of electromagnetic field quantities at a microscopic level can shed light on the process of SRM design, which in turn could create new opportunities for substantial improvement of SRM performance …
Design And Development Of Embedded Dsp Controllers For Power Electronic Applications, Raman Nair Harish Gopala Pillai
Design And Development Of Embedded Dsp Controllers For Power Electronic Applications, Raman Nair Harish Gopala Pillai
Electrical Engineering Theses
Power applications like motor drives, inverters have complex algorithms that can be used to improve their efficiency. More often reduced manufacturing cost takes precedence over better efficiency. DSPs with their high computational power can provide reduced cost and higher efficiency. Though the cost of a standalone DSP chip has reduced, its integration to form a complete embedded product is an area often overlooked. High frequency of operation, reduced package size, and sensitivity to component placement are some of the factors that affect the interface between input/output devices and the DSP. This thesis presents the design and development of an embedded …
A Physics Based Multi-Resolution Technique For Extraction Of Finite Duration Time Responses In Radar Images, Nancy Lanett
A Physics Based Multi-Resolution Technique For Extraction Of Finite Duration Time Responses In Radar Images, Nancy Lanett
Electrical Engineering Theses
This paper presents a wavelet multi-resolution technique for examination of scattering phenomena in radar images. Through multi-resolution frequency domain analysis, range gating is implemented for extraction of wave medium interaction phenomena. To analyze the data, a sliding range gate is implemented by applying a phase shift to the spectral domain far field data prior to wavelet analysis. A method for efficient removal of window effects, which occur due to the finite nature of the data, is demonstrated through reconstruction of the decomposed waveform following removal of the lowest resolution. A correlation of the physical meaning of the multi-resolution data to …
Design Of A Cmos Vco And Frequency Divider For 5 Ghz Applications, Prithvi Shylendra
Design Of A Cmos Vco And Frequency Divider For 5 Ghz Applications, Prithvi Shylendra
Electrical Engineering Theses
This thesis presents the design of a new CMOS Voltage Controlled Oscillator and a frequency divider, both of which form important blocks in the design of a PLL synthesizer. These components are important because they operate at the highest frequencies within the PLL and also consume most of the power as compared to the other components. Both these circuits have been an active topic of research in recent years especially with the scaling of technology bringing hopes of complete system-on-chip (SOC) integration at RF frequencies. The circuits in this thesis are designed for 5 GHz applications, mainly for the IEEE …
Fpga Prototyping For Fast And Efficient Verification Of Asic H.264 Decoder, Basavaraj Mudigoudar
Fpga Prototyping For Fast And Efficient Verification Of Asic H.264 Decoder, Basavaraj Mudigoudar
Electrical Engineering Theses
To improve compression efficiency, recent video compression standards such as H.264 use complex algorithms and various modes that demand more computational power. Consumer electronics industry requires a low power, compact and cost-effective implementation of video codec for most of the products. ASIC implementation of these video codecs is a logical choice to meet these requirements. Functional verification of an ASIC implementation consumes a major part of design cycle time and lot of resources. Because of large design, various modes and options, functional verification of an ASIC H.264 video codec is a challenging, resource intensive and time consuming process. In this …
Simulation And Characterization Of Znse/Bete Resonant Tunneling Diode On Silicon, Moshe Davis
Simulation And Characterization Of Znse/Bete Resonant Tunneling Diode On Silicon, Moshe Davis
Electrical Engineering Theses
ZnSe/BeTe resonant tunneling diodes were grown on silicon with a ZnxBe1-xTe buffer layer using MBE (Molecular Beam epitaxy).These devices were processed and characterized. The devices showed multiple NDR (negative differential resistance) regions at room temperature with PVR (Peak to valley ratios) between 1.01 to 1.23. Variations to the structure were made in growth and their corresponding current-voltage characteristics were studied. The ZnSe/BeTe resonant tunneling diode showed asymmetrical current voltage characteristics for positive and negative biases. The sources of asymmetry were investigated during fabrication and with the help of simulations. The Al/ZnSe contact was confirmed to be ohmic contact when the …
Structural Similarity Based Image Quality Assessment: Pooling Strategies And Applications To Image Compression And Digit Recognition, Xinli Shang
Electrical Engineering Theses
This thesis studies a recently proposed perceptual image similarity measure: the structural similarity (SSIM) index. Although still in its early stage, the SSIM index has demonstrated superior performance in a large number of tests as compared to the currently most widely used image distortion/quality measures, the mean squared error (MSE) and the peak signal-to-noise-ratio (PSNR). This motivates us to further investigate the SSIM method and extend it to other image processing and pattern recognition applications. Specifically, three topics have been studied in this thesis: spatial pooling strategies for perceptual image quality assessment, structural similarity-guided perceptual image compression, and handwritten digit …
Real-Time Data Monitoring And Manipulation For Wireless Sensor Networks, Sankar Bhanu Gorthi
Real-Time Data Monitoring And Manipulation For Wireless Sensor Networks, Sankar Bhanu Gorthi
Electrical Engineering Theses
The growth of Wireless Sensor Network research has brought about the need for tools to help developers rapidly develop applications for various platforms. In the pursuit of these capabilities, this work deals with the design of a graphical approach to development of Wireless Sensor Network applications for implementation in the LabVIEW Graphical Development Environment. The work done also covers the implementation and development of the Sound and Vibration Toolkit for LabVIEW. The implementation of these tools in developing a novel test-bed at the Distributed Intelligence and Automation Laboratory at the ARRI at UT Arlington is also shown. This work is …
Design And Hardware Implementation Of A Soft-Switched Converter For Fuel Cell Applications, Shiju Wang
Design And Hardware Implementation Of A Soft-Switched Converter For Fuel Cell Applications, Shiju Wang
Electrical Engineering Theses
The focus of this thesis is to design a DC-DC quasi-soft switched boost converter suitable for fuel cell applications. Study of electrical output characteristics of fuel cells was necessary for this purpose. A number of experiments were conducted to study the steady-state and transient response of fuel cell system under various load dynamics. The results of these findings were necessary for the next phase of the project which was to design a reliable and high-performance regulated DC-DC converter. The design goals were realized with a soft-switching boost converter (implementation of zero voltage switching (ZVS) and zero current switching (ZCS) schemes) …
Design Of An Enhanced Translinear Variable Floating Resistor And Its Application In A Vga, Nithya Jagannathan
Design Of An Enhanced Translinear Variable Floating Resistor And Its Application In A Vga, Nithya Jagannathan
Electrical Engineering Theses
An improved current controlled floating resistor is designed based on translinear loops for application in a Variable Gain Amplifier (VGA). This work compares the use of two different devices and evaluates the difference based on the model parameters and circuit performance. The different architectures employed clearly demarcate the performance variations. The translinear variable resistor exhibits a dynamic range greater than 60 mV. The resistance value lies in the range of 3 K? to few Ohms. A Current Feedback Operational Amplifier (CFOA) is also designed to have an f -3dB of 250 MHz. The CFOA together with the variable resistor in …
Feasibility Study Of Options For Aging Hydro-Power Generation Facility, Sandip R. Sharma
Feasibility Study Of Options For Aging Hydro-Power Generation Facility, Sandip R. Sharma
Electrical Engineering Theses
Most of the hydro generation facilities are operating under derated capacity due to various factors. The availability of generation facilities is decreasing, the cost for maintenance is going up and plants are crippled with severe faults leading to outages. The feasibility study for aging hydro-power plant is carried out with an objective to find out the best possible alternative both with respect to reliability of operation and benefit to cost ratio. The multi-criterion weighted average condition evaluation of hydro-electric generator is carried out. A Visual Basic and Microsoft Excel based condition evaluation program is implemented for possible condition decision making …