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Full-Text Articles in Electrical and Electronics

Computer Analysis Of The Electrocardiogram Using Hardware Digital Signal Processing, Mohammad Ashfaque Shaikh Sep 1988

Computer Analysis Of The Electrocardiogram Using Hardware Digital Signal Processing, Mohammad Ashfaque Shaikh

Theses

A system based on the microcomputer IBM PC-AT has been realized to acquire and filter the clinical electrocardiogram (ECG) data in real time. The system program further detects and analyzes the ECG signals for possible cardiac arrhythmias.

This research is based on work done by previous researchers and achieves significant goals towards achieving on-line arrhythmia detection using a microcomputer. The system uses the hardware and software package ASPI 320/PC from Atlanta Signal Processors Inc. This hardware configuration uses a special purpose instrumentation microprocessor ( TMS32010 from Texas Instruments) to coprocess the ECG signals. Coprocessing the signals with the ASPI 320/PC …


Waveform Analysis And Application To A Model Of The Egg Waveform, Eu-Rune Chang Sep 1988

Waveform Analysis And Application To A Model Of The Egg Waveform, Eu-Rune Chang

Theses

The purpose of thesis is to describe and investigate a model of electroglottogram waveform. At the beginning, we generate a set of sine waveform models to analyze by using Fourier transform theory. Then, according to the electroglottogram is conjectured to be related to the area contact between the vocal folds, we assume a simple model of vocal fold vibratory motion is used to estimate the vocal fold contact area as function of time. Therefore, we modified and developed the mathematic EGG waveform model by using personal computer program computation to become a set of realistic EGG waveform models, which are …


Clinical Base Station For Portable Patient Monitoring Equipment, Silin Kuang Aug 1988

Clinical Base Station For Portable Patient Monitoring Equipment, Silin Kuang

Theses

In today's clinical environment, where it is not always desirable to have a computer terminal present, a microcontroller-based biomedical system with multi-purpose features is needed. The present work offers an approach for a clinical based desktop workstation that provides the physician with record files, general management of his patient group, and specific algorithms for patient or group analyses. The workstation has the capabilities to acquire a large number of data from a portable patient monitoring device, generate a hard copy graphic record, create a patient cardfile and an . office personnel loggin file, and check patient's appointment and emergency list. …


Istemcr : Integrated System For Truck Engine Monitoring Via Cellular Radio, Tse-Shan Pan Aug 1988

Istemcr : Integrated System For Truck Engine Monitoring Via Cellular Radio, Tse-Shan Pan

Theses

The study presented is aimed at the application of the Data Acquisition to The Truck Engine as the source of all the signals, with the mobile telephone Cellular Radio system.


A Word Based Data Compression Using Arithmetic Encoding, Christopher Dean Peckham Aug 1988

A Word Based Data Compression Using Arithmetic Encoding, Christopher Dean Peckham

Theses

It is usually difficult to compress data from a statistically unknown source and yield a good compression ratio. Using the fact that words are the fundamental basis of the written language, a data compression scheme based on words should yield high compression ratios. Discussed here is a compression scheme that gathers words from the source stream and places them in a dictionary, or word list, to use later in the coding, thereby becoming adaptive to the words in a given file without prior knowledge of the source. When a word is in the word dictionary, it is encoded by its …


Data Extraction And Analysis In Glucose Monitor, Chang Qian Aug 1988

Data Extraction And Analysis In Glucose Monitor, Chang Qian

Theses

For the purpose of building a workstation to read and analyze data from hand-held, home use glucose monitor, a new high performance Digital Oscilloscope Peripheral (DOP) for PC is used to easy sample and store data, and it is described here. The new features of DOP are discussed and some application software packages for different purpose are described here in detail.

Since the sampled data from the hand-held, home use glucose monitor is irregular and in random form, the Least-Square Polynomial Modeling Method is used to produce a fit curve line, which best goes through most data points. Using the …


Implementation Of A Cross Coupled Phase Locked Loop System With Closed Loop Amplitude Control, Behzad Sadeghi Aug 1988

Implementation Of A Cross Coupled Phase Locked Loop System With Closed Loop Amplitude Control, Behzad Sadeghi

Theses

A system was designed, to demodulate an FM signal in presence of an interfering signal whose frequency was very close to the desired signal, this system was implemented and tested based on the theory of cross coupled phase locked loop systems, originaly proposed by (1).

This system included two phase locked loops for the purpose of demodulation, two low pass filters and two integrators, for the purpose of amplitude estimation. Two additional phase locked loops were designed to act as a 90° phase shifter. The following is the result of the theory, design procedure and some tabulated data for this …


Image Enhancement And Edge Detection Using Fuzzy Algorithm, Samir Patel May 1988

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 …


Research, Development, And Evaluation Of A Solid State Transformer, Robert Michael Joseph Wozniak May 1988

Research, Development, And Evaluation Of A Solid State Transformer, Robert Michael Joseph Wozniak

Theses

The analysis and design of a solid state step down transformer is presented as part of a research study which reviews novel approaches to the development of high frequency power magnetic apparatuses and applies available theory to produce a solid state counter part. The resulting circuit exhibits the potential for efficiency as high as 85%, low output ripple, regulation that is comparable with other modes of power conversion and the ability to provide localized on-board power.


Implementation Of The Voice Processing System, Yang-Young Dan May 1988

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 …


A Computer-Based Microwave Interferometer Instrumentation System As A Non-Invasive Cardiopulmonary Monitor, Chin-Yee Eric Ho May 1988

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 …


Contrast Sensitivity Measurement Via Evoked Potential, Ken-Gen Lu May 1988

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 …


A Silicon Photodiode Array For Soft X-Ray Sensing, Chih-Te Hu May 1988

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 VTP and VTN for the CMOS circuit components. The final CMOS chip dimension using MOSIS 1.2 micron rules is 10mm x 10mm base on the 80 …


System Performance Criteria In Cdma Networks Using Gold Codes, Yong H. Kim May 1988

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 May 1988

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 May 1988

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 May 1988

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 …


Temperature Dependent Reliability Of Plastic Packaged Microcircuits, Wasim Ahmed May 1988

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 …


Rf Characterization Of A Directly Modulated Ingaasp Buried Heterostructure Laser Diode, Charlotte Alvarez May 1988

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 May 1988

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 May 1988

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 May 1988

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 …


Effects Of Peripheral And Microwave-Core Heating On Survival In Hemorrhagic Shock In Rats, Ashraf Sabry El-Assuooty May 1988

Effects Of Peripheral And Microwave-Core Heating On Survival In Hemorrhagic Shock In Rats, Ashraf Sabry El-Assuooty

Theses

In a model of rats resuscitated from hemorrhagic shock,where 11 of 12 animals were alive up to 4 hours after shock, there was an average drop of 10°C in core body temperature. Survival and morbidity was much impaired when the shocked animals were externally heated with an infrared lamp to maintain a core body temperature of 35°C. Since the increased intrashock mortality is possibly due to the circulatory changes induced by peripheral heating, an attempt was made to determine the effects of heating the animal at its core. Twelve rats were shocked in the same fashion, however the body core …


Stepping Motor Control And Position Monitoring, Pei-Kuan Feng May 1988

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 …


Ibm/Xt-Based Automatic Monitoring Instrumentation System For Eating Behavior Studies In Rats, Binghong Gui May 1988

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 May 1988

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 May 1988

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 …


Failure Mechanisms Of Hermetically Sealed Solid Tantalum Capacitors, Syed R. Kazmi May 1988

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 May 1988

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 …


Independent Equations Method For Power System State-Estimation, Shun-Gee Lin May 1988

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 …