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Full-Text Articles in Electrical and Electronics

A Pitch Based Processor For The Analysis Of Steady State Laryngeal Modes, Tzyy-Jenq Lou May 1985

A Pitch Based Processor For The Analysis Of Steady State Laryngeal Modes, Tzyy-Jenq Lou

Theses

A data acquisition and analysis stem for use in the study of laryngeal dynamics has been built and tested. The special feature of the system is the computer controlled digitizing rate and coordinated subject pitch prompting. Tokens of steady state laryngeal vibration are obtained from an electroglottograph when the subject intones a series of computer prompted pitchs in a musically scalar sequence. The digital samples of this data are captured by the system at a basic rate of 200 samples per laryngeal cycle. This procedure enables the system to perform a modal analysis of laryngeal function, not unlike the analysis …


Pressure Distributions In Microvascular Network, David Moshenberg May 1985

Pressure Distributions In Microvascular Network, David Moshenberg

Theses

The objective of this study was to find a practical way of estimating the pressure distribution in a network of microvascular vessels. The pressure distribution was evaluated twice, namely before vasodilations or vasoconstrictions and after the network of vessels reached a new steady state with respect to pressure and flow. Along with determining the pressure distribtuion, the simulation also calculated an effective blood viscosity coefficient for the network.

Poiseuille's equation and the axial component of the equation of motion were used to evaluate the steady state pressure and velocity distributions in each vessel. The continuity equation (conservation of mass) was …


Microcomputer Controlled Continuous Activity Monitor For Small Caged Animals, Yogesh Parekh May 1985

Microcomputer Controlled Continuous Activity Monitor For Small Caged Animals, Yogesh Parekh

Theses

The task of this instrumentation system is to measure the activity of rats in a controlled experiment. The system is designed to work in conjunction with the system for studies of metabolic rates in rats. The interface circuits take the picture from a video (vidicon) camera into the computer. Once the picture frame is taken into the high resolution graphics screen memory area, the computer uses this data to detect the activity. The movements of the rat are detected by comparing the number of pixels changed between two consecutive picture frames. The area covered by the rat determines the standing …


16-Channel Signal Analyzer For Electroencephalograms, Junnyih Chiang May 1985

16-Channel Signal Analyzer For Electroencephalograms, Junnyih Chiang

Theses

An instrument has been designed to analyze 16 channels of EEG of a squirrel monkey by using several interface boards controlled by an Apple II computer. This instrumentation system is capable of performing these experiments in an automated manner. It stores the data generated on to a floppy disk, with software control and results may be printed out together with related graphs. Because of the limitation of the floppy disk capacity, we had only developed two versions:

(1) To average the EEG signal up to 8 times for all 16 channels, because a lot of memory is needed to save …


Determining Process Latitude With Electrically Measurable Test Structures, Jonathan Littlehale May 1985

Determining Process Latitude With Electrically Measurable Test Structures, Jonathan Littlehale

Theses

Collection of linewidth data is an important part of photoresist characterization. Linewidth data are usually collected by optical measurements or scanning electron microscopy. Both of these techniques are tedious and time-consuming. In this work, electrically measurable test structures are used to collect linewidth data. These structures use a measured sheet resistance, a known length of conducting material, and the measured resistance of the structure to determine the linewidth. The benefits of using these structures include completely automated data collection and the ability to collect statistically significant amounts of data. This allows the use of existing statistical analysis software to analyze …


Design Criteria Of Three-Phase Three-Element Power Directional Relay Under Asymetrical Faults, Fidelis Wagoela Dakogol Jan 1985

Design Criteria Of Three-Phase Three-Element Power Directional Relay Under Asymetrical Faults, Fidelis Wagoela Dakogol

Theses

An analytical investigation has been conducted on a three-phase three-machine network power system to determine the optimum Scheme of Connections of the three-phase three-element power directional relay in which the torques of the three independent dynamometer operate on a common axis providing mechanical summation of torques proportional to the power components at the terminals of different phases.

The operation of three-phase, three-element power directional relay is determined by the summation of current and voltage systems having the same phase sequences which is governed by the form of power expression that is proportional to the resulting torque for the various combinations …


Failure Rates And Leakage Current Increase In Tantalum Capacitors Of Different Manufacturers, Joseph G. Grant Jan 1985

Failure Rates And Leakage Current Increase In Tantalum Capacitors Of Different Manufacturers, Joseph G. Grant

Theses

This study has determined the effect of high humidity and temperature on solid tantalum capacitors, from five different sources.

The reasons for using capacitors from five different prestigious sources is to first determine how the parameters change with the different manufacturing techniques used by the different sources. Secondly to rank the different sources according to reliability. The parameters that were measured before and after the "1000 hour" high temperature and humidity test were, capacitance, leakage current, and equivalent series resistance. All the capacitors showed significant increase in leakage current after the test, but there were wide variations in catastrophic failure …


Reliability Screening Of Transformers, Bharat M. Shah Sep 1984

Reliability Screening Of Transformers, Bharat M. Shah

Theses

The purpose of this project is to study screening of components from the reliability point of view. The component used is electronic transformer. The screen chosen is Electrical Noise generated in the transformer insulation system and the failure mode selected is leakage current in the transformer insulation.

Experiments were conducted to monitor electrical noise generated due to partial ionization of the tiny air gaps in the transformer insulation. The voltage stress, regiured to be applied to the insulation system, for constant 59 units of noise, recorded for the sample of three hundred seventeen transformers.

The voltage readings were analyzed statiscally …


Performance Comparison Of Digital Communication Signaling Schemes, Hiroshi Okusawa Sep 1984

Performance Comparison Of Digital Communication Signaling Schemes, Hiroshi Okusawa

Theses

The intent of the work "Performance Comparison of Digital Communication Signaling Schemes" is to consider various signaling schemes for digital communication and their relative performances.

In order to gain a better perspective of the overall problem of digital communication signaling, the most basic ideas, such as conceptual techniques for the generation and detection of modulated signals, are outlined and provided.

The primary measure of performance -for a digital communication system is the error rate. Emphasis is placed on analyzing the probability of error for various idealized signaling schemes.


A Method For The Identification Of Parameters In Nonlinear Time-Varying Discrete Systems, Somo Coulibaly Sep 1984

A Method For The Identification Of Parameters In Nonlinear Time-Varying Discrete Systems, Somo Coulibaly

Theses

The purpose of this thesis is to present a new technique for estimating the unknown parameters of nonlinear discrete time-varying systems.

The method is based on the model-reference control system where the model and the plant are controlled to exhibit the same output trajectory. The model is chosen to be linear and stationary. To develop the procedure of identification we assume that the structure of the nonlinear system is known and all the measurements are free of noise. A feedback input is adapted to improve the scheme. This scheme can be used to simultaneously identify the parameters when the control …


Modeling And Analysis Of Switching Dc-To-Dc Converters, Suresh Hariharan Sep 1984

Modeling And Analysis Of Switching Dc-To-Dc Converters, Suresh Hariharan

Theses

Modeling and analysis of switching dc-to-dc converters has been achieved through several techniques. The state space averaging technique is valid only for disturbances which are less than one-tenth the switching frequency. The discrete technique does not yield accurate results. In this thesis a new approach to the stability analysis of switching regulators has been discussed and the model is far more accurate than the state space averaging technique or the discrete technique. It can be easily programmed into any computer and the results compare well with the experimental results. It also gives a good insight into the design of the …


Optimization Of The Sputtering Technology For Preparation Of Hg1-[Subscript X] Cd[Subscript X] Te Heterojunction Diodes, Kyriacos Kokkinos Sep 1984

Optimization Of The Sputtering Technology For Preparation Of Hg1-[Subscript X] Cd[Subscript X] Te Heterojunction Diodes, Kyriacos Kokkinos

Theses

The deposition of (Hg1-xCdx)Te onto Si and (Hg1-yCdy)Te (x>y) substrates by rf triode sputtering was studied. Ionized mercury vapor, in the 0.6 to 1.2 micron pressure range, was used to bombard pressed-powder targets, consisting of HgTe and CdTe particles, with effective target x value of 0.3, 0.35, and 0.4. The sputtering procedure, parameters, and system were modified to optimize film characteristics. Higher substrate temperature (270°C) was required to obtain metallic gray films with x>0.3. With substrate temperatures less than 270°C and deposition rates 0.5-1.0 micron per hour the films were …


Computer Based Instrumentation System For Measurement Of Cardiac Output In Small Animals, Prasad L. Gavaskar May 1984

Computer Based Instrumentation System For Measurement Of Cardiac Output In Small Animals, Prasad L. Gavaskar

Theses

The task of the instrumentation system is to measure cardiac output in animals like rats, dogs, etc. A thermal-dilution method is used for this purpose. The temperature change due to injection of saline is picked up by thermo-couple microprobes implanted in the blood-vessel. The signal after conditioning is fed to a data acquisition system controlled by a computer.

With the help of a computer it is thus possible to monitor and control an experiment on several animals. The computer can sample the chambers sequentially. The sampling cycle duration and frequency are programmable. The data is collected and processed to determine …


Automated Instrumentation System To Monitor Behavioral Experiments, Dilip S. Gokhale May 1984

Automated Instrumentation System To Monitor Behavioral Experiments, Dilip S. Gokhale

Theses

An instrumentation system has been designed to monitor behavioral experiments on monkeys. This instrumentation system is capable of performing these experiments in an automated manner without any human intervention. It is capable of monitoring these experiments concurrently in six boxes. It exhibits several features that make it more versatile than previous instrumentation systems. It is also capable of storing the data generated on to a floppy disk and later transmitting it to the mainframe.

Another feature that makes it more versatile is the flexibility of the system. Presently it is configured to run experiments with variable interval schedules. However with …


Reliability Studies On Solid Tantalum Electrolytic Capacitors, Hamed Nassar May 1984

Reliability Studies On Solid Tantalum Electrolytic Capacitors, Hamed Nassar

Theses

The primary objective of this thesis is to determine and analyze the failure mechanisms of solid tantalum capacitors, pinpoint the causes, and suggest the precautionary measures that prevent the occurrence of these failures. To achieve this goal, the study went in two directions, theoretical and experimental. The theoretical part-is a comprehensive review of the work -done on tantalum capacitors since 1960 up to date.

The experimental part of the study is a life test (1000 hours) of solid tantalum capacitors under humidity and high temperature. To avoid the misconception that could happen by investigating a particular manufacturer's product, units from …


Magnetohydrodynamic Synchronous Generator With Exhaust Divertor Plasma Of Fusion Reactor, Prabir Kumar Majumdar May 1984

Magnetohydrodynamic Synchronous Generator With Exhaust Divertor Plasma Of Fusion Reactor, Prabir Kumar Majumdar

Theses

It is the intent of this thesis to develop design concept of a MHD-Synchronous generator for generation of A-C electric power utilizing the exhaust divertor plasma of Tokomak fusion reactor.

The main physical structure of the MHD-Synchronous generating system consists of (1) a linear induction accelerator at the divertor channel to accelerate the plasma velocity sufficient enough to provide rotational effect on the exhaust cylinder by turbine action; (2) a D-C field coil as a source of magnetic field at the entrance of the exhaust chambers; (3) turbine blade on the upper portion of the cylindrical current sheet and (4) …


Computer Simulation Of Electro-Static Field Potential To Study The Effect Of An Animal On The Electric Field Between Two Charged Plates, Shekhar Gajanan Potdar May 1984

Computer Simulation Of Electro-Static Field Potential To Study The Effect Of An Animal On The Electric Field Between Two Charged Plates, Shekhar Gajanan Potdar

Theses

This thesis deals with plotting of equipotential lines in an electrostatic field created by two parallel charged plates. Between the plates lies a dielectric cage inside which an animal (rat) is kept, on whom anatomical tests are to be carried out after exposing it to a certain electric field intensity for a given period. Values of the actual field to which the animal is exposed can hardly be obtained experimentally. Computer simulation in this case becomes a powerful tool. Starting with the uniform field ideally created between two parallel plates, it is then neccesary to find the effect of the …


An Investigation Of Characteristics Of Blood Velocity In A Simulated Circulation System, Yung-Gang Wu May 1984

An Investigation Of Characteristics Of Blood Velocity In A Simulated Circulation System, Yung-Gang Wu

Theses

The major objective of this thesis is to find the relationship between the blood velocity and the stenosis of the vessel. Tests were performed with different degrees of stenosis at varied logitudinal positions from the testing probe in the vessel of a Z-80 microprocessor controlled artificial circulation system.

Three methods were used to detect the velocity in the vessel: continuous wave Doppler, Pulse Doppler, and a hot-film device. The first method can get the average velocity, while the latter two have the capability to find a velocity profile, and all are important indicators to the arterial occlusion phenomenon.

An analysis …


Instrumentation To Measure Ion Flux Through Biological Tissues, John Edward Obenauer May 1984

Instrumentation To Measure Ion Flux Through Biological Tissues, John Edward Obenauer

Theses

An instrument has been designed and constructed which measures the ion flux through biological tissues utilizing the short circuit current technique. The system operates in three major modes: 1) obtains the fluid resistance and potential offsets of a chamber without the tissue mounted; 2) Voltage clamp mode - clamps the potential of the tissue to a predetermined value; 3) Current clamp mode - clamps the current through the tissue to a predetermined value. The system automatically compensates for fluid resistance and potential offsets in both voltage and current clamp modes. The instrument starts clamping a particular chamber immediately after mounting …


The Detection Of Partial Discharges In Transformer Oil, Gerald J. Fitzpatrick May 1984

The Detection Of Partial Discharges In Transformer Oil, Gerald J. Fitzpatrick

Theses

The level, meaning the number and the intensity Of partial discharges that occur in transformer oil per time period of applied pulse when a high voltage is applied can be used as a measure of the quality and remaining life of the oil. The level of partial discharges at a given applied voltage can be correlated with the degree of contamination of the oil by impurities such as water and conductive particles and can be used as an indicator of the proximity of the oil to breakdown. There are several approaches to the detection of partial discharges, e.g., acoustic measurements, …


Microcomputer Controlled Instrumentation System For Studies Of Metabolic Changes In Rats, Murat Dertlioglu May 1984

Microcomputer Controlled Instrumentation System For Studies Of Metabolic Changes In Rats, Murat Dertlioglu

Theses

The system measures the respiratory exchange in rats in a controlled experiment. An interface unit provides data, received from several measurement instruments such as gas analyzers, an electronic flowmeters, electronic thermometer and an electronic hygrometer, to the computer. The data is gathered from different chambers in a multiplexed mode.

The computer samples the chambers sequentially and prints out the results and stores them on the disk. The sampling duration of each chamber and the number of the rats to be tested can be programmed. The system can perform experiments with twelve animals, in the following arrangments, either one group of …


Performance Modeling And Simulation Of Multiple Microcomputer Systems, Moorthy Narayana Hariharan May 1984

Performance Modeling And Simulation Of Multiple Microcomputer Systems, Moorthy Narayana Hariharan

Theses

Multiple processor systems are the logical choice for applications demanding high computing power, throughput and reliability. Moderately coupled Multiple Microprocessor systems can be applied to a variety of applications demanding high performance. The structure of Multiple Microprocessor systems is examined. Various interconnection structures are analysed for performance comparisons.

Queueing theory is a powerful tool in modeling and analysing Computer systems. Queueing models are developed for popular Multiple processor interconnection topolog es like the Shared memory, Shared bus, Star and Loop configurations.

The usefulness of Digital computer Simulation techniques in estimating the performance of Multiple processor systems is demonstrated through a …


Decision Rules Applied To Spread Spectrum Signal Detection, Richard Jae Kim May 1984

Decision Rules Applied To Spread Spectrum Signal Detection, Richard Jae Kim

Theses

Decision rules for detection of spread spectrum signals were investigated. For each decision rule, error and erasure probabilities were analyzed. The obtained data was used to plot PE vs Pe for constant signal-to-noise ratio (SNR). With the use of the probability of a word error curves the optimum threshold setting was found for a given SNR.

FSK (orthogonal signalling) and PSK (antipodal signalling) were considered for modulating the chips. When the PE vs Pe plots for FSK and PSK were compared, PSK performed better than FSK by a ratio of 6 dB.

Finally, analog and digital correlation of the received …


Spectral Analysis Of Brainstem Auditory Evoked Responses, Amir Hossein Massumkhani Oct 1983

Spectral Analysis Of Brainstem Auditory Evoked Responses, Amir Hossein Massumkhani

Theses

In this study, the power spectrum density of the brainstem auditory evoked responses is estimated by the method of periodogram. Several techniques for reducing the leakage due to the finite length of data, smoothing the spectrum and reducing the ambiguity in the spectrum due to the resolution are studied. It is shown that a Hamming window reduces the leakage considerably and zero extention of the data to 512 points produces sufficient spectrum bandwidth. Three major peaks are observed at 100, 500, and 1000 Hz which are stable for different evoked responses. In one case with a delayed wave V, the …


Data Acquisition And Parameter Identification In Electro-Oculography, Wolfgang Poelzleitner Sep 1983

Data Acquisition And Parameter Identification In Electro-Oculography, Wolfgang Poelzleitner

Theses

Electro-Oculography (EOG) is used in clinical ophthalmology to measure the time response of the corneoretinal potential (CRP) to changes in light intensity. An automatized data acquisition and system modeling link has been developed that significantly reduces processing time presently required for EOG. The data acquisition is performed on a microprocessor based instrument, which supervises the EOG-test, measures the potential and, after completion of the test, transfers the results to a mainframe computer. Parameter identification routines provide graphical representation and mathematical models for the CRP. Both nonlinear curve fitting methods and Least Squares System Identification schemes are used.


The Role Of Electrical Noise In Screening Transformers Prone To Failure, Rajeev D. Shirodkar May 1983

The Role Of Electrical Noise In Screening Transformers Prone To Failure, Rajeev D. Shirodkar

Theses

Insulation used as a barrier between the high voltage and low voltage windings of a transformer has sites of in- homogeneities like pinholes, cracks or voids, developed during the manufacturing process. Thus, these minute air pockets are stressed much more than the solid dielectric, on the application of a voltage stress, because the dielectric constant of the solid insulation is many times that of the air dielectric. As a result, excitation or ionization takes place in the air (gases). The amount of excited or ionized molecules is proportional to the volume of the inhomogenei- ties within the insulation.

Therefore, experiments …


Gallium Nitride Film Deposition By Ionized Cluster Beam Epitaxy, Ghulum Bakiri May 1983

Gallium Nitride Film Deposition By Ionized Cluster Beam Epitaxy, Ghulum Bakiri

Theses

An experimental Ionized Cluster Beam System similar in design to the one developed at Kyoto University in Japan was. designed and constructed in the Microelectronics Laboratory at NJIT. This involved making the working drawings, having the parts machined and then assembling the system in a vacuum system together with the necessary variable power supplies, meters, controls, gas inlets, cooling water connections, etc.

Eleven deposition runs were then attempted to grow gallium nitride utilizing the system constructed. In a typical deposition run, gallium was vaporized from a boron nitride crucible at 1000° C and allowed to expand through a 0.5 mm …


An Experimental System For Observation Of The Rat Coronary Microcirculation Using Digital Image Processing, Wolfgang Braun May 1983

An Experimental System For Observation Of The Rat Coronary Microcirculation Using Digital Image Processing, Wolfgang Braun

Theses

A system was constructed which allows direct observation of the coronary microcirculation of the beating rat heart. An EKG triggered strobe is used on the microscope light source to "stop" the action of the beating heart so the surface microvessels can be observed di rectly under the microscope. Experimental results are recorded on videotape and played back for frame-by-frame analysis of the data using digital Image processing techniques such as digital filtering, image extraction, image enhancement and edge detection.

The application of image enhancement techniques (high order and low order enhancement methods ) as well as edge detection using a …


A Parameter Identification System For The Human Visual Evoked Response, Robert Kalle Michaels May 1983

A Parameter Identification System For The Human Visual Evoked Response, Robert Kalle Michaels

Theses

The Human Visual Evoked Response (VER) provides a useful tool for analyzing an individual's visual system. However, mere inspection of the signal may not always be the best way to make a diagnosis of the patient. To aid in this diagnosis a parameter identification system has been developed which fits the response to an analog model. The development of the model was based on the results of a survey of previous work in the field. Data were acquired from a data acquisition/processing system developed at the New Jersey University of Medicine and Dentistry and the Eye Institute of New Jersey. …


Automated Instrumentation System For Studies Of Metabolic Rates In Rats, Suhas P. Pathak May 1983

Automated Instrumentation System For Studies Of Metabolic Rates In Rats, Suhas P. Pathak

Theses

The task of the instrumentation system is to measure the respiratory exchange in rats in a controlled experiment. Air is drawn at a predeter-mined rate in and out of rat chambers. The proportion of oxygen and carbon dioxide in the ensuing air indicates the respiratory rate of the rat. The entire operation is controlled by a microcomputer whose most important functions are: to direct the flow of air through the rat chambers by switching valves; and to collect data about the percentages of gases in question.

Thus with the help of a computer it is possible to monitor and control …