Electrical and Electronics Commons^™

A Computer-Based Microwave Interferometer Instrumentation System As A Non-Invasive Cardiopulmonary Monitor, Chin-Yee Eric Ho

Theses

The system comprises a microwave interferometer as a computer-based non-invasive cardiopulmonary monitor. The microwave interferometer records the mechanical vibration of the chest wall. The objective is to determine whether the signals may have diagnostic value and to evaluate the instrument as a non-invasive and non-contacting cardiopulmonary monitor.

With the help of a computer it is possible to analyze the mechanical vibration of the chest wall produced by the heart and thereby detect, and possibly categorize, cardiac abnormalities. This system is able to process two channels, the first signal from microwave interferometer records chest wall vibrations and the second signal is …

Independent Equations Method For Power System State-Estimation, Shun-Gee Lin

Theses

The problem of power system state estimation (PSSE) is to convert the available. redundant and noise contaminated measurements, and other information into a best estimate of the state of the system.

Methods to solve the PSSE, including the sub-problems of bad data presence detection, identification and reconstruction, are reviewed. The Independent Equations Method (IEM) was selected for in-depth study and analysis.

The tree method for bad data identification is tested and failed due to the suspected ill-conditioning of the sensitivity matrix. For bad-data reconstruction, the IEM fails as described. Modifications that saves computing time and ensures reconstruction success are presented …

Reliability Problems In Semiconductor Lasers, Ajay R. Patel

Theses

The stability and reliability of semiconductor laser is dependent on its design, fabrication, and output power. The best way to assure high reliability of these devices is by accelerated aging test and by selection of strict and meaningful criteria for the acceptance or rejection of a particular device. In this thesis emphasis is given on different failure mechanisms that are known. As new development takes place, other mechanisms may be found. Catastrophic degradation, gradual degradation, darkline defects, and contamination during the fabrication process are the main source of device failure.

The noise generation and the packaging issue of semiconductor laser …

Temperature Dependent Reliability Of Plastic Packaged Microcircuits, Wasim Ahmed

Theses

Increasing power and power densities in new high complexity semiconductor devices are creating heat removal problems. Increased powers produce higher junction temperature which lead to potentially faster degradation of device reliability. Thermal management at device level packaging involves efficient and cost-effective removal of dissipated thermal energy from the device to assure its reliable performance over the long term. In the context of very high levels of integeration of future ICs, thermal management will mean making such devices possible close to the limits of acceptable high temperature.

The major factors affecting heat flow in a plastic Dual-in-line-packages (DIP'S) are investigated using …

Development Of 8052ah-Basic Based Single Board Computer Ii, Suping Lou

Theses

8052AH-BAISC Based Single Board Computer II ( SBC II ) is designed and developed for the application in biomedical instruments as an embedded central processing unit. SBC II offers powerful function in digital signal acquisition, storage and processing, smart on-board EPROM programming, various preipheries supporting and custom supervisor program. The techniques of design and development of SBC II includes computer aided circuits analysis and schematic, optimal design algorithms and computerized setting up SBC II prototype.

This thesis combines the analysis of SBC II circuitry, set up and operation of the complete computer aided electrical circuit design software OrCAD/SDT specifics in …

Design Of Bridge Inter-Connecting Token Ring & Token Bus Local Area Networks, Kasinath Anupindi

Theses

A Bridge interconnecting two Local Area Networks has been modelled. The two interconnected networks are the Token Ring and the Token Bus LANs. Concepts of Queueing theory have been employed in the design. Initially it is assumed that the buffer size at the Bridge is infinite. Further it is assumed that the arrival rate of the messages is Markovian and the service rate is General, Le it is an M/G/1 system. Expressions for the average waiting time at the Bridge and the size of the buffers is computed. Graphs for various parameters have been plotted. Based on these graphs the …

Implementation Of The Voice Processing System, Yang-Young Dan

Theses

The Voice Processing System is implemented by using XILINX Advanced Computer Aided Design Technology. It is also used as an interface to the 8052 AH-BASIC single hoard computer system.

The Voice Processing System ( VPS ) comprises three major parts:

1. Voice Detection Circuit

2. System Clock Generation & Synchronization

3. Signal Processing and Storing Circuit

The analog voice sip!gnals are the inputs to the first part of VPS. The digitalized voice is the output of this system.

In order to get precise output, the first part plays the roles of noise cancellation, zero crossing processing, and recognition.

For the …

Image Enhancement And Edge Detection Using Fuzzy Algorithm, Samir Patel

Theses

A method of image enhancement and edge detection by computer using the fuzzy set is illustrated. The algorithm involves extraction of fuzzy properties corresponding to pixels and then succesive application of fuzzy operator 'contrast intensification' along with smoothing in the fuzzy property plane before detecting its edges. The property plane is extracted from the spatial domain using S, π, and (1- π) functions and the fuzzifiers. Edge detection is achieved using KIRSH operator. A computer routine is developed and the effectiveness of the algorithm with different value of the system parameter is demonstrated on different images. The digital computer HP …

Reliability Evaluation Of Liquid Crystal Displays Under Accelerated Test Conditions, Ishatdev Singh Rathore

Theses

This thesis deals with the recent study of reliability of liquid crystal displays. This study determined the effects of high temperature on LCD reliability. To accomplish this, reliability life testing was done on different kinds of LCD samples under different operating conditions. The tests were carried out on the samples of two different vendors at two different temperatures. No humidity was added in any test.

Vendor No. 1

1. 120 units at 77° ± l° C.

2. 80 units at 85° ± 1° C.

Vendor No. 2

1. 60 hard and 60 soft glass units at 77° ± 1°C.

2. …

Design Of An Experimental Apparatus To Measure The Charge And Mass Of Ionized Species In A Partially Ionized Cluster Beam Deposition System, Nitin K. Shah

Theses

The objective of this research was the design and construction of an experimental apparatus to investigate the size distribution of gallium clusters that can be emitted from a heated crucible with a 1 mm nozzle. This research work involved the design and construction of a partially ionized cluster beam (PICB) deposition system which would provide low charged particle background for retarding field analysis and cluster size measurements. The apparatus also allowed control of critical parameters on which the cluster size may depend.

The promise of PICB is based on the formation of clusters of adatoms, their ionization and their acceleration …

Analysis And Simulation Of Chirp Radar System, Tina Tsung Tsai

Theses

This paper consists of a technique to design a Chirp radar system and proposes a solution to optimize the design of the linear time delay network required in such systems. A Chirp radar system has a wide bandwidth for high range resolution, and long pulse duration for high velocity resolution and high transmitted energy. The technique of a pulse compression system offers a means of increasing the average power available to illuminate radar targets without any loss of the resolution at the receiver needed for the tactical requirements of the system. This is accomplished by transmitting a wide pulse in …

A Silicon Photodiode Array For Soft X-Ray Sensing, Chih-Te Hu

Theses

An array of 30 x 30 sensing cells including logic within each cell and a self-scan address circuit are described. A unique scintillation technique is used to increase the threshold sensitivity 60dB for X-ray photon sensing beyond that obtainable with conventional photodiode sensors. Simulations for the sensing cell and some additional logic elements are based on SPICE version 2G5 and HILO 3. Worst case analysis includes variations in threshold voltage V_TP and V_TN for the CMOS circuit components. The final CMOS chip dimension using MOSIS 1.2 micron rules is 10mm x 10mm base on the 80 …

Investigation Of Different Cmos Dram Sense Amplifier Configurations In Vlsi, Bihju Chiu

Theses

Sense amplifiers are particularly difficult circuits to design. In this work, only CMOS sense amplifiers are considered. There are typically two configurations of CMOS sense amplifiers: the cross-connected flip flop configuration and the current-mirror configuration. They are widely used nowadays with various modifications. These improved configurations are simulated and optimized with SPICE package, and their relative performances are also compared in this thesis.

On Conventional And Harmonic Load Flow Analysis, Ranjit B. Pradhan

Theses

In conventional power flow analysis, simultaneous linear equations numbering in thousands must be solved repeatedly and in many instances on-line. Luckily the matrix of coefficients of these equations is sparse with a few elements in each row. Therefore for a faster solution and to save computer memory, sparsity must be exploited and an optimal ordering of the equations must be sought. When considering harmonics, the number of the simultaneous equations to be solved is multiplied and therefore, considering sparsity and optimal ordering is doubly important.

In this thesis a software package for optimizing computation time and memory requirements through exploitation …

System Performance Criteria In Cdma Networks Using Gold Codes, Yong H. Kim

Theses

First, we have presented the autocorrelation and crosscorrelation properties for periodic and aperiodic binary sequences. The generation of binary sequences using shift registers with feedback was reviewed. We have also included correlation properties for the Gold codes.

Next, we discussed Gold code generation for the balanced and unbalanced Gold codes.

Thirdly, we investigated the number of simultaneous users in a CDMA system using Gold codes for the worst case and the average case of mutual interference.

Finally, we simulated the probability of interference exceeding a threshold value, and the average crosscorrelation value caused by interference in a CDMA network which …

Modeling And Simulation Of Robot Arms With Flexible Links, John G. Danis

Theses

The design of lightweight robot arms introduces a degree of flexiblity in the individual links which renders the arm difficult to control. Solution of the control problem requires accurate and detailed mathematical models of the arm dynamics. A comprehensive survey of the current literature in this area has shown that although many such models exist, there is a great diversity in their structure, function, and applicability. The different objectives and techniques of model development which lead to this diversity are examined and summarized in this thesis. Bases for classification of the mathematical models and techniques of development are established, and …

An Investigation Of Electrical And Optical Properties Of Reactively Sputtered Silicon Nitride And Amorphous Hydrogenated Silicon Thin Films, Tae Hoon Kim

Theses

Thin films of silicon nitride and amorphous hydrogenated silicon were prepared by radio frequency reactive sputter deposition and their properties optimized for their use as low temperature passivation coatings for optoelectronic devices. The effect of various sputter deposition parameters on the conduction and optical properties were studied. Infrared spectrophotometry and ellipsometry were used to determined the optical properties of the films whereas the electrical properties were determined from current-voltage measurements of MIS capacitors.

Typical parameters of a sputter deposition run for the best Si₃N₄ films were: base pressure, 1-2x10^-6 torr; sputtering pressure, 5 mtorr; nitrogen partial …

Design Of A Fiber Optic Oxygen Sensor Based On Immobilized Hemoglobin, Mendu Govind Raj

Theses

The fiber optic Oxygen sensor consists of a thin layer of immobilized deoxyhemoglobin at the common end of a bifurcated fiber. Immobilization is done using the alginate gel procedure. The immobilized reagent is separated from the standard oxygen sample by the gel with or without semi-permeable membrane, and the entire configuration is enclosed in an oxygen free sample cell. Light from a tungsten-halogen lamp, filtered through a 405nm filter is passed through one arm of a bifurcated fiber to the sample cell. The reflected intensity (a highly polished aluminum foil or a plate is placed at the bottom of the …

Rf Characterization Of A Directly Modulated Ingaasp Buried Heterostructure Laser Diode, Charlotte Alvarez

Theses

The use of fiber optics for the transmission of microwave signals had its beginnings in 1984. Applications were limited to the lower microwave frequency regions. Technology in this field is advancing rapidly due to the high demand driven by the telecommunications community for high speed digital applications. Extensive research and development efforts are underway by both the component manufacturers and the subsystem end user. Most of the near term applications of microwaves in fiber optics are in weapon systems and communication systems for military and other government agencies.

The high frequency modulation characteristics of Lytel's InGaAsP 1300 nm buried heterostructure …

Data Flow Dependency Generator, Chin-Piao Chan

Theses

Data flow is a new approach to parallel computing. The concept is to enable the execution of an instruction whenever its operands become available. The only constraints in a data flow machine are the data flow dependencies between instructions.

In this thesis, a simulation package called the Data Flow Dependency Generator is developed. This package is designed to express the idea of data flow computations, the data flow dependencies and the use of multiprocessors.

Given a number of processors, a number of time units for each operation and a program, the Data Flow Dependency Generator finds the data dependencies between …

A 3-D Tactile Sensor With Digital Output, Sin-Shou Cho

Theses

This thesis details the design of a new tactile sensor for general-purpose robot manipulators. Such manipulators, designed to be functionally equivalent to the human hand, will require sensor arrays that fulfill several requirements : (1) many sensor elements to minimize tactile imaging time, (2) close spacing of small sensing elements for fine spatial discrimination, (3) ability to be molded to a convex fingertip surface for taction on concave surfaces, (4) tolerance to over-scale forces without damage. In addition to the above, which are considered requirements, several other characteristics are desirable. Foremost is the ability to sense shear forces, which provide …

Stepping Motor Control And Position Monitoring, Pei-Kuan Feng

Theses

Stepping motors provide precise digital control of speed, without speed detector feedback. A stepping motor can produce a large torque for a relatively small displacement, without a shaft-position sensor or special compensation. This provides accurate control of motor position. This thesis describes the development of stepping motor torque characteristics and the different approaches stepping motor phase current waveform detection. It is shown that one of the most useful indicators of rotor position is the initial rate of current rise. The Hybrid, Permanent-magnet and Variable-reluctance step motors have been applied in the drive circuits. The open-loop control circuits are implemented to …

An Investigation Of Interrupt Handling Schemes In Pipeline Processors, Shailesh Ratilal Gami

Theses

In order to acheive higher performance in a pipeline processor, proper interrupt handling is essential. In a pipeline processor, interrupt handling is difficult because many instructions are in the processor at the same time. This study describes and evaluates the different solutions to interrupt handling. Several pipelined 32-bit microprocessors have also been studied and their architectural and programming features are compared.

The Tapered Dielectric Rod-Conical Antenna, Nicholas I. Georghiades

Theses

The problem of the linearly tapered dielectric rod/conical antenna, excited by the HEI1 hybrid mode in a metallic circular waveguide , is rigorously studied. A theoretical model, and numerical investigation for the radiation characteristics of such an antenna are presented. The model is based on the combination of classical analysis of the Electromagnetic Fields within the dielectric rod, Local Mode Theory, and the Equivalence Principle for the determination of equivalent current distributions.

The far-zone radiation field is considered to be the summation of the fields produced by two radiative components in the dielectric rod/conical structure: The "aperture" of the uniform …

Ibm/Xt-Based Automatic Monitoring Instrumentation System For Eating Behavior Studies In Rats, Binghong Gui

Theses

An auto-feeding system based on the IBM-XT microcomputer has been designed for use in the anti-obesity research program in the Pharmacology Department at Hoffmann-La Roche Inc. By using this system, experimental rats can be automatically fed, some which have been given anti-obesity drugs and some which have not. The system can also collect data, such as eating times and food intake, which are used for studying the rat's eating behavior.

The system is designed to control thirty six cages with one experimental rat in each cage and it performs three functions:

1 ) To automatically dispense a preset quantity of …

Microcomputer-Controlled Respiratory Rate Monitor, David John Hartmann

Theses

In order to measure the metabolic change in an animal due to the administration of anti-obesity drugs, an instrument was constructed which will allow the continuous sampling of twelve individual animals residing in enclosed chambers. The instrument is based on the principle of Indirect Calorimetry, which measures metabolic rate by sampling the inlet and outlet concentrations of respiratory gases (oxygen and carbon dioxide) of the chamber. The system is controlled by an IBM PC which will control six chambers or twelve chambers simultaneously.

The system assesses the metabolic rate of the animal by calculating the Respiratory Quotient (RQ) and the …

Performance Of Single Dwell Serial Synchronization System, Chan-Yee Hsiung

Theses

By using the sampling theorem, the problem of the detection of a signal in white Gaussian noise, reduces to the consideration of the sum of the squares of statistically independent Gaussian variates. If the transmitter and and receiver are not synchronous, then no data transmission is possible and the decision statistic has a central chi-square distribution. Otherwise, the decision statistic has a non-central chi-square distribution. Also, this. paper presents a method to calculate the mean and variance of the acquisition time which are the most important parameters to evaluate the performance of a PN spread synchronization system. In addition, the …

The Application Of Zero-Sum Games To Low Sensitivity Optimal Control, Jun Huang

Theses

This thesis deals with the synthesis of low sensitivity optimal control systems. Zero-Sum games are applied to the first order linear differential equation system. The goal is to obtain an optimal control of the system performance, and at the same time, reduce the sensitivity of the performance index and sensitivity trajectory.

In this thesis, the quadratic index of performance is selected in the argumented system which is combined/ the system equation with the sensitivity equation. Two control variables U & V are selected to maximize and minimize the system, in order to obtain the optimal value of the system.

Two …

Reliability Of Packaging In Microcircuits, Zia Iqbal

Theses

The semiconductor industry is faced with the problems of how to increase the level of reliability of semiconductor parts being used in the electronic systems which have had their lifetimes extended through new and better system design.

This paper deals with the reliability of packaging constructions commonly used in large scale integration / integrated circuits and will present the failure mechanisms and failure modes which can arise when proper processing is used. In addition, the materials used in each construction and how they affect reliabilty will be analyzed.

It is not the intention of this paper to present any new, …

Failure Mechanisms Of Hermetically Sealed Solid Tantalum Capacitors, Syed R. Kazmi

Theses

This study has determined the failure mechanisms of solid tantalum capacitors and their causes. It was observed that high leakage current and electric shorts are the most prominant modes of failure. The experimental data has proved that humidity and high temperature are the factors which promote these kinds of failures. It is also stablished that change in electrical parameters due to exposure to harsh weather are reversible. Vacuum treatment to such capacitors helped in improving their electrical characteristics.