Electrical and Electronics Commons^™

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 …

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 …

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 …

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.

Apap: The Arithmetic Pipeline Analysis Package, Chang-Chieh Lin

Theses

This study is aimed at the development of an interactive PC-based package for simulating data flow within an arithmetic pipeline in multiprocessor systems. The user constructs the arithmetic pipeline, specifying the functionality of each segment, the intersegment connectivity and pipeline inputs and outputs. After defining reservation tables and data, analysis is performed with the results available in tabular, simple graphic and animated graphic forms.

APAP allows the user to design hardware and analyze its functionality with-out building the circuit, an economical alternative. Even when circuits are to be built, APAP allows the user to correct logic errors before implementation, leaving …

An Analysis Of The Second-Order, Type-One Hilbert Phase-Locked Loop, Inn-Shian Lin

Theses

In this thesis, a second-order, type-one PLL ( Phase- Lock, Loop ) in which the usual lead-lag loop filter is paralleled with a Hilbert Transformer (the whole system is called HPLL) is analyzed. A motivation for the study was that earlier researchers have found improved performance if Ilse lead-lag network is paralleled by a differentiator, result mg in the so called ERPIM (Extended-Range Phase-Locked Demodulator). For the purpose of com-parison with earlier experimental and analytical results on the PLL and the ERPLD, the numerical results in this thesis ale based on the parameters of Acampora and Newton.

The basic characteristics …

Simulation Study Of The Multi-H Continuous Phase Modulation, Min-Ling Lin

Theses

Of particular interest in satellite communications are modulation techniques that have a relatively constant envelope and are power and bandwidth efficient. Attempts have been made to satisfy these requirements by using phase and frequency modulation formats. Recently, one approach has been researched which combines the modulation and encoding functions, which is referred to as multi-h continuous phase modulation. Simultaneously good power and bandwidth efficiencies can be achieved at the expense of increased complexity.

This report examines the performance of multi-h continuous phase modulation by a simulation. A multi-h phase coded modulation is generated, passed through the AWGN transmission channel. The …

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 …

Gallium Arsenide Standard Cell Cad Database For Digital Design, Nanchou Liu

Theses

This thesis develops a selected design database of gallium arsenide logic cells for automated design. Uniformly applied 1 um gate length physical layout rules are used for the design database with a standard cell design methodology.

Schottky Diode FET Logic (SDFL) technology with double level metallization was selected following a consideration of alternative gallium arsenide MESFET logic types. The SDFL approach is judged to provide improved noise margin, production yield, density, and lower power dissipation.

A cell library with 60 um cell height has been implemented with double entry for each cell input/output. Each cel1 has been simulated with SPICE …

Contrast Sensitivity Measurement Via Evoked Potential, Ken-Gen Lu

Theses

This work is concerned with the use of the visual Evoked Response (VER) to determine Contrast Sensitivity in humans. For this purpose, a system has been developed where signals, obtained from scalp electrodes, and stimulated by visual grating patterns, are recorded digitized and processed on a personal computer (IBM compatible). Processing includes signal averaging and digital filtering. The system provides storage, retrieval and graphic representation of data as well as the capability to transfer data to other computer systems. Data processing includes parameter estimation of suitable signal models, which provide effective data compression of the signal into a finite set …

Asics Application On Voice Processing Interface Design- Qegg Multiplier, Gwo-Jen Luar

Theses

Application Specific Integrated Circuits (ASIC) is a high density VLSI design that including the lower cost, higher performance, small size, and increased reliability. The ASIC, XILINX's LCA is applied on the signal processing ahead of computer I/O interface, specially for the quantitative Electroglottograph. This thesis covers the logic design, simulation test, realization, and stand alone test.

Interface To 8052ah-Basic Microcontroller For A Multichannel Priority Interrupt System, Chen-Tung Mo

Theses

This thesis presents the design and development of a system with the capability to detect up to forty channels of signals generated from different analog sources and to process them under the control of a microcomputer.

The present work offers the design and implementation of a hardware interface unit in a multichannel real-time data acquisition system as well as the application software program to operate it. This kind of system can be widely used in process control, musical instrument interfacing, and machine automation.

This interface unit follows the general instrumentation architecture in both signal processing and logic control. The software …

A Dynamic Set-Based Multiaccess Protocol For Local Area Networks, Parul S. Nanavati

Theses

The packet-broadcasting technique brings together the advantages of both packet switching and broadcast communication. The central problem of a packet broadcast network is conflict resolution among the users sharing the broadcast communication link. Collisions are the major source of transmission errors which degrade the performance of a LAN. Proposed here is a novel multiaccess protocol which offers full communication resources to the user at low traffic requirements. It dynamically adjusts the number of users allowed to access the medium at heavy traffic requirements such that number of collisions are reduced and thus maintains the efficient utilization of the medium and …

Design Criteria Of Coherent Optical Fiber Communication System, Rajesh N. Patel

Theses

Design criteria of coherent optical fiber communication system were discussed and investigated. First, the different types of optical fibers (waveguides) were discussed. Then the laser sources, photo-detectors, transmitter & receiver circuits were discussed in detail.

Design criteria of conventional intensity modulated (direct detection) optical fiber communication system were discussed. Then, the design criteria and estimation of number of photons for different modulation schemes for coherent optical fiber communication system were analyzed.

Coherent optical fiber communication system's advantages and drawbacks were discussed in detail. Improvement in receiver sensitivity of coherent detection compare with conventional direct detection was investigated. Finally, some receiver …

Microprocessor Testing And Computer Aided Diagnosability Of Digital Circuits, Shirish Patel

Theses

Computer Aided Diagnosability Of Circuits (CADOC), a new method is developed for isolating and pin-pointing a faulty device in digital circuits. CADOC is based on graph-theoretic principle and PFD numbers. Without considering any SA1 or SAO faults, we can zoom out faulty device by selecting different diagnostic path to narrow down the faulty region and to isolate the faulty device. The efficiency of this new technique is confirmed by applying the technique to many examples.

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 And Development Of An Infrared Ccd Camera, John Frederick Romanowich

Theses

An infrared CCD camera system was designed and developed for operating various sizes of Schottky-barrier IR-CCD image sensor chips. The camera has a digitally programmable frequency synthesizer for operating the 160 X 244, 320 X 244, and 256 X 256 image sensors developed at the David Sarnoff Research Center. The electronics of the camera are designed to provide the outputs required for operating a XYZ monitor, a standard TV monitor, or a computer workstation. At the core of the camera design is a RS-170 standard sync generator that supplies the waveforms for synchronizing the camera's circuitry to produce a composite …