Electrical and Electronics Commons^™

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 …

Reliability Problems And Failure Mechanisms Of Solid Tantalum Capacitors, Ghanshyam B. Nakrani

Theses

Today, reliability is acknowledged as an important item in design and the operation of the electronic systems.

This thesis provides some theory, and experiments are instituted to evaluate the reliability for SOLID TANTALUM CAPACITORS made by different manufacturers. The experimental life test work was done at high temperature of 9S 2°C and high humidity of 95 ± 3% on transfer molded tantalum capacitors.

Literature study concentrates on the reliability in solid tantalum capacitors developed between 1961 and 1984.

Several failure mechanisms with figures are illustrated to point out how higher reliability of solid tantalum capacitors may be developed.

The bibliography …

Computerized Instrumentation System For Indirect Measurement Of Metabolic Changes In Rats, Holger Tebbje

Theses

This work describes the further development of a system for the measurement of the energy expenditure of rats. Based on the concept of indirect calorimetry the respiratory exchange is monitored in a controlled experiment. Rats are held in cages through which air is drawn and analyzed. Transducers and sensors, interfaced to the computer, are measuring the composition and the physical parameters of the gas entering and leaving the chambers. The data recieved is processed, displayed on a screen, printed and stored for later analysis.

The accuracy and repeatability of the system improved by measuring additional parameters like barometric pressure and …

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 …

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 …

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

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

Theses

The deposition of (Hg_1-xCd_x)Te onto Si and (Hg_1-yCd_y)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 …

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 …

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 …

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 …

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

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 …

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 …

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, …

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 …

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 …

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 …

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 …

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. …

Moment Method Solution Of The Time-Dependent Transport Equation To Describe The Scattering Of Gaussian Plane Wave Pulses By A Forest, Nack Yang Cho

Theses

The time dependent transport equation is used to study the transmission of periodic pulses through a forest. The forest is assumed to occupy a half-space region, to be statistically homogeneous and to scatter energy isotropically A periodic sequence of Gaussian plane wave pulses is assumed to enter the forest normally from free space. The transport equation is solved by the moment method using triangular expansion functions. Numerical results indicate the dependence of the incoherent intensity on penetration depth, observation angle, albedo and pulse repetition rate.

Error Detection For Data Communication Systems, John Biancamano

Theses

A description of the problems encountered in the data communications field and the various solutions can be found in a number of diverse, and often theoretical sources. My intention in writing this thesis is to bring together, in a practical and understandable manner, the theory and the application of a method of error detection used extensively in data communication systems known as the Cyclic Redundancy Check (CRC).

To provide some background on the subject, a description of a data communication system is presented, and the possible sources of error are explored in some detail. Data transmission formats are described, and …

Adaptive Delta Modulation, Aliuddin Ahmad

Theses

The objective of this thesis is the study of the performance of instantaneously companded adaptive delta modulation (ADM) systems in comparison with linear delta modulation (LDM) in terms of signal to quantization noise ratio (SNR). Various schemes for ADM are discussed and their advantages and disadvantages are indicated. SNRs are calculated by simulation, with IBM's continuous system modeling programming (CSMP) language being used as a tool for simulation. LDM, first and second order constant factor delta modulation (CFDM), has been simulated and responses for different types of input signals are presented.

Pattern Generation And Fault Detection In Digital Circuits Using A Microprocessor, Syed Riffat Ali

Theses

The main object of this Professional Project was to establish a microcomputer based system which could detect faults in digital circuits. Hardware and software for the Motorola 6800 microcomputer system was fully developed. Node level diagnostic programs were then used to pump known "Bit Patterns" into digital circuits and responses recorded via Pseudorandom binary sequence generator using CRC code. This method also known as "Signature Analysis" was then applied to detect faults successfully in Universal Asynchronous Receiver Transmitter or UART Circuits.

Study Of Compositional Changes (Altered Layer) In (Hg,Cd)Te Targets Sputtered With Hg Vapor, Robert Granville Bourne

Theses

Six mercury cadmium telluride targets (5.74 cm diameter) with six polycrystalline (Hg_0.8 Cd_0.2 )Te ingots (1 x 3 x 0.7 cm ± 20%) epoxied on them, were r.f. sputtered in an MRC-8800 triode system for 1, 2, 3, and 5 minutes. The six sputtering runs were made with 3 different Hg pressures of 1.0, 1.25, and 1.6μm while the uniform target power density was kept constant at 7.7W/cm². After sputtering a target, Br₂ +CH₃OH was used to chemically etch the sputtered ingots to different depths. The surface composition of the etched ingots was …

A Microprocessor Based Digital Logic Simulator, Kevin Dresher

Theses

It is the intent of this thesis to acquaint the reader with a tool which is available for use in the digital circuit design field. The reader is now able to totally simulate via DLS the digital logic design he creates on paper before it ever takes a hardware form. The computer program accepts a detailed description of the schematic and creates timing diagrams, loading statistics, cross references, and various lists for future documentation.

The user needs no programming knowledge and will find the requirements to run a simulation with DLS extremely user oriented. The simulation descriptions and command language …

A New Mathematical Model For Nephron Macromolecular Selectivity, John Anthony Domiter

Theses

A mathematical model describing the displayed selectivity of the kidney nephron to macromolecules of varying particle size is presented. Diffusion and electrical forces are considered to be the sole mechanisms of transfer. The mass transfer principles responsible for selectivity are considered to occur within the capillary structure, and not within the membrane wall. A charge is assumed to be characteristic of the macromolecule and the membrane wall. Models describing both charged and uncharged solutes are developed.

A non-linear least squares technique, developed by Marquardt, is used to curve fit the derived functions to data relating fractional clearances of dextran and …

The Measurement Of Depolarized Radiation For Monitoring The Mass Concentration Of Particulates, Bruce E. Wilson

Theses

The depolarization of backscattered polarized incident radiation which is expressed as a depolarization ratio was investigated as a means of monitoring the mass concentration of particles in stacks from coal-fired burners. This involved the design of an instrument that would detect small levels of radiation. Two methods were investigated. The first utilized a Gallium Arsenide laser and a silicon detector diode; the second was composed of a xenon flash lamp and a photomultiplier detector tube.

The relationship between the depolarization ratio and the mass concentration of diamond particles in the 0.01 gm/m³ to 0.5 gm/m³ was determined. Diamond …

Sparsity And Decoupling In Load Power Flow Analysis, Kenneth Nazimek

Theses

This paper presents some recent ideas on and methods created by power engineers for the solution of the Load Flow Problem. Beginning with an analysis of the solution of large systems of linear equations, techniques employing elementary matrix operations are discussed to reduce the amount of calculations necessary to achieve repeated solutions. Recent interest in taking advantage of the characteristic sparsity of the admittance matrix is also examined. The problems of operating on and computer storage of large sparse matrices are investigated. Methods to efficiently order, store and work with large sparse matrices are discussed and demonstrated. The general acceptance …

Dynamics Of The Glucose-Insulin-Glucagon System, Joseph P. Hartmann

Theses

A computer model for the Dynamics of the Glucose-Insulin-Glucagon System has been developed for a 17.5 kg canine using the Continuous Systems Modeling Program (CSMP) for the 360 Computer System. The major body components controlling the glucose dynamics (liver, pancreas, body muscle, blood flow, and body fluid compartments) have been modeled in terms of either their production, absorption, or transport of glucose, and the concentration levels of both the hormones and substrates perfusing the body component. A set of mneumonics has also been developed to label the hundreds of constant and variable terms required to describe a complex system of …