Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 30 of 45
Full-Text Articles in Engineering
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.
Neural Network Solution For Fixed-Final Time Optimal Control Of Nonlinear Systems, Tao Cheng
Neural Network Solution For Fixed-Final Time Optimal Control Of Nonlinear Systems, Tao Cheng
Electrical Engineering Dissertations
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 …
Physical Layer And Application Layer Issues Of Wireless Sensor Networks, Lingming Wang
Physical Layer And Application Layer Issues Of Wireless Sensor Networks, Lingming Wang
Electrical Engineering Dissertations
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 …
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 …
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 …
Dynamic Stability Analysis Of Large-Scale Power Systems Using A Fast Investigation Method, Ming-Tse Kuo
Dynamic Stability Analysis Of Large-Scale Power Systems Using A Fast Investigation Method, Ming-Tse Kuo
Electrical Engineering Dissertations
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 …
Generation Planning And Market Operation Strategies In The Southwest Power Pool Energy Imbalance Service Market, Kittipong Methaprayoon
Generation Planning And Market Operation Strategies In The Southwest Power Pool Energy Imbalance Service Market, Kittipong Methaprayoon
Electrical Engineering Dissertations
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 …
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 …
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 …
Performance Analysis And Design Of Space-Time Codes, Chen Liao
Performance Analysis And Design Of Space-Time Codes, Chen Liao
Electrical Engineering Dissertations
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 …
Models And Algorithms To Determine Cerebral Activation Using Near Infrared Spectroscopy, Monica Suresh Allen
Models And Algorithms To Determine Cerebral Activation Using Near Infrared Spectroscopy, Monica Suresh Allen
Electrical Engineering Dissertations
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 …
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 …
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 …
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 …
Monitoring And Fault Diagnosis Of Multiconverter Power Electronic Systems, Ranjit Jayabalan
Monitoring And Fault Diagnosis Of Multiconverter Power Electronic Systems, Ranjit Jayabalan
Electrical Engineering Dissertations
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 …
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 …
Device Level Vacuum Packaged Microbolometers On Flexible Substrates, Aamer Mahmood
Device Level Vacuum Packaged Microbolometers On Flexible Substrates, Aamer Mahmood
Electrical Engineering Dissertations
Micromachined microbolometers on flexible substrate have been fabricated and characterized. Liquid polyimide PI5878G made by HD Microsystems has been used to form the flexible substrate. Semiconducting Yttrium-Barium-Copper-Oxide (commonly referred to as YBCO) is the temperature sensitive material. These detectors are supported by thin micromachined layers of silicon nitride on flexible polyimide PI5878G. The devices were characterized for temperature dependent resistance (R(T)), the temperature coefficient of resistance (TCR, ), responsivity , detectivity (D*) and thermal conductance (Gth). A typical device had a resistance of 3.76 MI and a TCR of -2.63 %/K at 301 K. The measured thermal conductance was W/K. …
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 …
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, …
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 …
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 …
Rf Mems And Integrated Manufacturing For Miniaturized Millimeter-Wave Systems, Ying Cai
Rf Mems And Integrated Manufacturing For Miniaturized Millimeter-Wave Systems, Ying Cai
Electrical Engineering Dissertations
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 …
Electromagnetic Wave Scattering From Vegetation, Xiaoyan Huang
Electromagnetic Wave Scattering From Vegetation, Xiaoyan Huang
Electrical Engineering Dissertations
This dissertation contains the theoretical study of microwave scattering from vegetated media and the development of microwave scattering models with applications to these media. A vegetation canopy may consist of deciduous or coniferous leaves, branches, and trunks with certain size and orientation distributions. The formulation of the scattering model for each element of the canopy is carried out and its scatter patterns versus its size and orientation for like and cross polarizations are computed and presented. In particular, an extension is made where vegetation with a compound-leaf pattern is considered. For this type of vegetation, several leaves that form a …
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 …
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 …
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 …
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 …
Web-Based Real-Time Monitoring System To Enhance The Participation Of An Industrial Power System In A Restructured Utility Industry, Shun-Hsien Huang
Web-Based Real-Time Monitoring System To Enhance The Participation Of An Industrial Power System In A Restructured Utility Industry, Shun-Hsien Huang
Electrical Engineering Dissertations
The opening of the Electric Reliability Council of Texas (ERCOT) grid to wholesale competition began in 1996 that initiated the first stage of deregulation in Texas. In order to relieve generation and transmission constraints, load reduction is considered as a form of available energy and spinning reserve. Afterward, power system becomes more dynamic and creates more opportunities for both electricity suppliers and consumers. Currently, both power supplier and demand consumer can participate in the energy and ancillary services (AS) markets to bid/offer for their energy, capacity, and demand in the ERCOT markets. In order to act as an effective market …