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Removal Of Contaminants From Clay Soils By Thermal Desorption, Wen-Ming Mao May 1989

Removal Of Contaminants From Clay Soils By Thermal Desorption, Wen-Ming Mao

Theses

The objective of this study was to investigate the removal of contaminants from clay soils by thermal treatment. There were two phases involved in this project. The first was a study of equilibrium adsorption of clay - organics study, and the second was the determination of the thermal desorption characteristics.

Three organics, phenol, chlorophenol, and chlorobenzene and one clay soil, bentonite, were selected for these studies. The first phase, involved the simulation of the isothermal adsorption simulated the process of contaminants being sorbed onto bentonite. Three different isotherm models,viz, Linear isotherm, Freundlich isotherm, and Langmuir isotherm were evaluated with experimental …


Study Of System Dynamics In A Primitive Identification/Counter Model, Zofia Monczka May 1989

Study Of System Dynamics In A Primitive Identification/Counter Model, Zofia Monczka

Theses

Previous study of a simplified identification/counter model (1), (2) indicated bifurcations in its behavior. In order to study this topic, graphical representations of the system dynamics are derived. Analysis of the structure of the identification/counter model reveals the reasons why the graphs assume their given shapes.

The graphical representations of the system are used to characterize the system behavior and thus explain the bifurcations previously encountered. These representations are then used as the basis for deriving a general model for system behavior. Analysis of this model for a specific range of parameter values indicates that the system contains numerous additional …


Survival Rate Study Of Intrashock Versus Postshock Microwave Rewarming In Rats Subjected To Hemorrhagic Shock, Hani M. Patel May 1989

Survival Rate Study Of Intrashock Versus Postshock Microwave Rewarming In Rats Subjected To Hemorrhagic Shock, Hani M. Patel

Theses

In search for a more effective treatment for rewarming of profound accidental hypothermia, a comparative survival rate study was conducted of intrashock versus postshock microwave rewarming in rats subjected to hemorrhagic shock. In an anechoic chamber, rats were illuminated with 50 Watts of continuous microwave power supplied by a 915 MHz microwave generator. This frequency corresponds to a free-space wavelength of about 33 cm. The incident-power density was calculated to be about 8.5 mW/cm2, and the whole-body specific absorption rate (SAR) was calculated to be 14.5 W/kg.

The microwave postshock group showed a significantly higher post shock survival rate than …


Hardware And Software Designs For Integrated Electrical Engineering Experiments, Sujin Pramojaney May 1989

Hardware And Software Designs For Integrated Electrical Engineering Experiments, Sujin Pramojaney

Theses

The interfacing between the various electrical engineering fields is not emphasized in the electrical engineering laboratory; the traditional aim of a laboratory course is to complement a single theoretical course. The object of this thesis is to provide means, hardware and software, that can be used in different system configurations to perform useful industrial tasks. The chosen task is to control electrical machines using a microcomputer. Experiments can be written to be performed by students, using these systems. The emphasize of these experiments can be on the characteristics of a power electronics device, but the device will be seen as …


Network Realizability Approach To Robust Stability Of Discrete-Time Systems Characterized By Polynomials, Sri Indran Rasiah May 1989

Network Realizability Approach To Robust Stability Of Discrete-Time Systems Characterized By Polynomials, Sri Indran Rasiah

Theses

In system design, the coefficients of a characterizing polynomial are usually not precisely known but can be bounded from above and below by real numbers. The requirement of robust system design from the stability standpoint demands, then, the guaranteeing of the stability of a set of polynomials.

Stability theorems for continuous-time systems and discrete-time systems, are studied in this report. It is shown that one more condition has to be included into each of the theorem. The revised theorem for continuous-time systems is proved through network realizability theory. The one for discrete-time systems is, then, proved via the use of …


Program Analysis Tool For Extensive Reverse Software Engineering : A Tool To Understand The Software (Patern), Bubulal R. Rawal May 1989

Program Analysis Tool For Extensive Reverse Software Engineering : A Tool To Understand The Software (Patern), Bubulal R. Rawal

Theses

This thesis describes a computer aided software engineering tool called Program Analysis Tool for Extensive Reverse software eNgineering (PATERN). Conceptually, PATERN provides systems analysts/programmers with a powerful tool independent of programming language, operating system, and programmer style of coding for documenting existing software. PATERN has been tested with C code in the UNIX environment. This thesis also describes the interface between PATERN and two subsystems that interact with PATERN: relational databases and data flow diagram generators. The implementation of these interfaces was investigated using Informix and another software tool, Directed Acyclic Graphs (DAG) for generating hierarchical structure charts and flow …


Digital Image Restoration Using Power Spectrum Equalization Filtering Technique, Debdatta Sen May 1989

Digital Image Restoration Using Power Spectrum Equalization Filtering Technique, Debdatta Sen

Theses

Digital deblurring of micro-circulatory images using both homomorphic and power spectrum equalization filtering are considered. An existing homomorphic filter was modified by changing filter parameters. This permitted an image with better contrast to be obtained. The power spectrum equalization approach consists of modeling and characterization of degradation and estimation of the power spectrum of the image using the Welch method. The restoration is considered from the point of view of spatial-frequency domain descriptions of images. Consideration is restricted to degradations arising from additive noise and spatially invariant linear blurring. The filter restores the power spectrum of the image to what …


Multiphase Solid-Liquid And Solid-Liquid-Gas Mixing In Stirred Tanks, Jessyca Susanto May 1989

Multiphase Solid-Liquid And Solid-Liquid-Gas Mixing In Stirred Tanks, Jessyca Susanto

Theses

A number of investigations can be found in the literature on the effect of mixing parameters on solid-liquid dispersions in agitated systems. However, the determination of the effect of impeller clearance on minimum suspension speed has received little attention. This work is mainly focused on the determination of the effect of the impeller clearance on Njs (the minimum agitation speed required for complete solid-liquid dispersion) and its corresponding power consumption, using both radial and axial impellers in stirred tanks. In addition, the effect of other significant parameters on Njs was also investigated.

The importance of the impeller clearance …


Thermal Desorption Of Phenol Contaminated Clay Soils, Chia-Ling Ting May 1989

Thermal Desorption Of Phenol Contaminated Clay Soils, Chia-Ling Ting

Theses

Clay mineral/organic reactions have been studied extensively by a numerous physicochemical methods. There also has been extensive research done in the areas of adsorption, Lewis acid-base reactions, desorption, adduct formation. Many of these studies explain the role and dehydration of silicates.

Studies have shown through extraction, thermal analysis, and gas chromatography. That there is more than one type of bonding, weak and strong, taking place between the clay mineral and the organic waste.

In order to determine the practicality of the containment technology, this research has been investigated by using more powerful tools, such as thermogravimetric analysis, differential scanning calorimetry …


Analysis On Dielectric Resonators, Xuan Tu May 1989

Analysis On Dielectric Resonators, Xuan Tu

Theses

This dissertation deals with the studies and analysis of Dielectric Resonators (DR). A shielded dielectric iesonator structure, consisting of the substrate, the spacer, the dielectric resonator and the metallic shielding is modelled theoretically. The theoretical expressions for the resonance fields are derived by using radial-mode matching and axial mode-matching techniques. In these techniques, the structure is divided into partial regions and the fields in each pai tial region are represented in terms of a series of the appropriate modes with unknown coefficients. Matching the adjacent regions yields a system of linear or nonlinear equations — which then are solved. The …


Arithmetic Pipeline Analysis Package Ii, Sai K. Vedantam May 1989

Arithmetic Pipeline Analysis Package Ii, Sai K. Vedantam

Theses

This work describes the implementation of arithmetic pipeline scheduling algorithms, to enhance an existing simulation package. The user need only specify the arithmetic equations to be processed and the required stage configuration. The program automatically performs the tasks of forming the reservation table, building the pipeline and specifying the input/output connectivity for each segment and multiplexer in the pipeline. This package integrates two existing simulation tools and enhances many aspects of the previous programs.

The main application area for such a tool is education. Since it is very easy to use and requires little or no time for one to …


Trellis Coded Partial-Response Channels, Kumari Yalamanchili May 1989

Trellis Coded Partial-Response Channels, Kumari Yalamanchili

Theses

Binary partial-response channels with transfer functions (1+D), (1-D) and (1 — D2) are intersymbol-interference channels which find applications in baseband data communications and magnetic recording systems (tapes, discs, compact discs, etc.). In this thesis we develop a coding technique for improving the reliability of digital transmission over noisy partial-response channels with the above transfer functions. We do so by introducing a new concept, called matched encoding, which arises in the context of trellis coding for channels with memory.

We use inner and outer trellis coding of the partial-response channels. The inner codes called matched inner coset codes, are …


The Effects Of Position And Gender In Evaluating Job Factors, Yen-Yueh Yin May 1989

The Effects Of Position And Gender In Evaluating Job Factors, Yen-Yueh Yin

Theses

This study investigated the extent to which corporate recruiters and students share an understanding of desirable job factors. To identify the differences between the two groups, 114 students and 26 recruiters completed a questionnaire on twenty three job factors. Univariate analyses revealed significant differences between the two groups. The implications of these findings for recruitment, selection, and career counseling are discussed.


Methods Of Achieving High Speed On Data Flow Machines, Chung-Lin Yu May 1989

Methods Of Achieving High Speed On Data Flow Machines, Chung-Lin Yu

Theses

Simultaneity is a key to high speed and large computation. Assuming hardware components of a given speed, it is the only remaining consideration in achieving raw speed. Simultaneity can be shackled by dependencies, however, and years of hardware and software work have been devoted to understanding the types of dependencies and how they can be obeyed or removed from a computation.

In this thesis, the principles of the data flow machines and the structure of the data flow languages are illustrated. Various methods of achieving high speed are discussed. These methods include streams, Lenient Cons (I-structure), and dependence-driven computation, which …


Image Coding With Switchable Dynamic Quantizers, Shing-Sun Yu May 1989

Image Coding With Switchable Dynamic Quantizers, Shing-Sun Yu

Theses

In this thesis, an image coding scheme based upon dynamic quantizations and Differential Pulse Code Miodulalton (DPCM) is studied for application in digital image transmission. This scheme achieves a degree of data compression, and at the same time, maintains an acceptable degraded Mean Square Error (MSE) in the reproduced image. The image to be transmitted is first divided into blocks and each block is then quantized before transmission. The dynamic quantizations including DPCM) are dynamically utilized in reducing the transmission rate while maintaining a desirable quantization noise level. Results of computer simulation of the proposed scheme demonstrate that the switchable …


Caldac, A New Approach To Computer-Assisted Theatrical Lighting Design, David William Zalewski May 1989

Caldac, A New Approach To Computer-Assisted Theatrical Lighting Design, David William Zalewski

Theses

CALDAC, which stands for Computer-Assisted Lighting Design and Control, is a design environment integrating two present day state-of-the-art theatrical lighting computer aides, the computer-aided design (CAD) program and the preset storage system. The CALDAC environment also features On-Screen Stage Simulation, a newly proposed design tool. It is shown that this integration offers a strong advantage to the lighting designer and his/her crew.

The thesis begins by introducing the concepts of theatrical lighting design and the evolution of computerized control. The basics of CAD for the lightplot design are presented, followed by an introduction to the concepts of on-screen stage simulation. …


Surfactant Enhanced Scrubbing In An Ejector Venturi Scrubber Of Sulfur Dioxide From Air Exhaust Streams, Humberto Roman May 1989

Surfactant Enhanced Scrubbing In An Ejector Venturi Scrubber Of Sulfur Dioxide From Air Exhaust Streams, Humberto Roman

Theses

The objective of this work was to determine the feasibility of applying the Surfactant Enhanced Scrubbing technique to the removal of sulfur dioxide using an ejector venturi scrubber.

Surfactants were chosen according to information from manufacturers. Those surfactants which offered good behavior in the presence of acidic solutions ( low pH ), and anti-corrosion characteristics were tested.

In the first phase, experiments were performed to determine the behavior of the foams in the ejector venturi scrubber. A foam destruction system was used when foaming conditions required it. In the second phase dynamic runs were performed to determine the removal efficiencies …


Algorithms And Analysis Of Dialogue Time Patterns, Muhammad Saleem Akhtar May 1989

Algorithms And Analysis Of Dialogue Time Patterns, Muhammad Saleem Akhtar

Theses

The characteristics of a conversation between two people can be determined not only what they say to each other, but also by the rhythm of their dialogue. Their moods, attitudes and attributes may be conveyed in part by time patterns of the speech. The programs described herein can be useful in exploring the relationship between dialogue time patterns and other psychological aspects of human behavior. The measurements of these time patterns can be quickly, inexpensively, and reliably accomplished by the use of a PC.

The programs described herein are capable of calculating the variabilities, the time durations and frequencies of …


Unified Study Of Trellis Encoded Correlative-Fm, K. Narendra Bhat May 1989

Unified Study Of Trellis Encoded Correlative-Fm, K. Narendra Bhat

Theses

Trellis encoding of correlative-FM is studied from the point of view of the overall structure, performance, bandwidth occupancy, and complexity. Here, correlative (partial-response) coding is used to improve the bandwidth efficiency of MSK (Minimum-Shift Keying) at the expense of performance. Then, trellis codes are used to improve the error-rate performance of the corresponding correlative-FM scheme with little or no increase in bandwidth occupancy (compared to uncoded MSK). In a sense, this is similar to Ungerboeck's coding for (memoryless) PSK modulation.

A new encoding approach, called matched encoding, is used here that produces trellis coded modulations achieving greater coding gains than …


Non Invasive Monitoring Of Cardiovascular Dynamics Through A Microwave Interferometer, Suresh Chakravarthi May 1989

Non Invasive Monitoring Of Cardiovascular Dynamics Through A Microwave Interferometer, Suresh Chakravarthi

Theses

The microwave interferometer is utilized to pick up vibrations of the anterior (front) chest wall, produced by cardiac activity. This instrument is capable of remotely measuring the vibrations at distances up to four feet through clothing, by using low level microwave energy at 9.3 Ghz. The vibrations picked up from subjects are filtered, and processed through a PC to correlate with EKG signals, and thereby evaluate the instrument as a non-invasive, non-contacting cardiac monitor.

The subjects lie on their back with the microwave energy illuminating their chest, and their cardiovascular dynamics are recorded simultaneously with EKG signals. The EKG is …


Transverse Electric (Te) And Transverse Magnetic (Tm) Mode Conversion In Optically Active (Chiral) Embedded Polymeric Waveguides, Mingdeh Chien May 1989

Transverse Electric (Te) And Transverse Magnetic (Tm) Mode Conversion In Optically Active (Chiral) Embedded Polymeric Waveguides, Mingdeh Chien

Theses

Wave propagation in an optically active isotropic, polymeric thin film waveguides is studied. The waveguides are fabricated using the dipping method. Thin film layers are composed of a passive PMMA (poly methyl methacrylate) host material and a chiral, optically active, ((s)-(+)-1,1'-Binaphthyl-2,2'-dily hydro phosphate), guest material. Experimental results show about 1° per centimeter rotation of polarization as light propagates through a 1.8cm waveguide. The theoretical analysis of the mode structure and wave propagation in the waveguide are examined using first order coupled mode theory. TE (-4 TM mode converter is a typical application of this investigation.


Interpolation Search For Alphabetic Tables, Loizos Gabriel May 1989

Interpolation Search For Alphabetic Tables, Loizos Gabriel

Theses

One of the fastest search techniques for uniformly distributed sorted numerical tables is interpolation search. This divide and conquer technique accesses the most probable key rather than the middle key as in binary search and continues to search similarly the appropriate part of the table . In the previous work we proved a lg lg n average number of accesses for interpolation search.

The inefficiency of interpolation search for an alphabetic table is demonstrated by Burton and Lewis and a robust variation suggested by them to improve the efficiency. This inefficiency is expected since such tables are usually far from …


One-Dimensional Parametric Inverse Scattering For Lossless Dispersive Media, Frank Gangi May 1989

One-Dimensional Parametric Inverse Scattering For Lossless Dispersive Media, Frank Gangi

Theses

In this thesis, the effects of high frequency noise on a perturbational inversion algorithm for a stratified dispersive medium are investigated. It is shown that the perturbational algorithm becomes unstable under high frequency noise. The physical origin of this instability is discussed.

In order to enhance the robustness of the perturbational inverse scattering solution, a parametric inversion algorithm is implemented. The improvement by the use of a parametric inversion is given quantitatively by the profile-to-error ratio (PER). Examples of the two-pole and the three-pole reflection coefficients are compared and contrasted.


A Computer-Aided Instruction Electrical Safety Course, Edward John Gusciora May 1989

A Computer-Aided Instruction Electrical Safety Course, Edward John Gusciora

Theses

It is the purpose of this thesis to show how computerized training can be used in helping to create an effective safety program. Through example, a complete electrical safety program will be developed for workers whose jobs do not pertain directly to electrical installations, but who use them through the course of their daily work activities. A computer-aided instruction module on electrical safety will be developed for presentation to workers on an IBM compatible computer.

Importance of Thesis

Too often safety factors go into the design criteria of a piece of equipment or a manufacturing process and do not extend …


Thermal Decomposition Of Dichloromethane In Hydrogen/Oxygen/Argon Mixtures And In Pure Oxygen, Wen-Pin Ho May 1989

Thermal Decomposition Of Dichloromethane In Hydrogen/Oxygen/Argon Mixtures And In Pure Oxygen, Wen-Pin Ho

Theses

The thermal decomposition of Dichloromethane in hydrogen/oxygen mixtures and argon bath gas was carried out at 1 atmosphere total presure in tubular flow reactors of varied surface to volume (S/V) ratio. The thermal degradation of dichloromethane was analyzed systematically over temperature ranges from 610 to 820°C, with average residence times in range of 0.1 to 2.0 seconds. Five reaction sets in three different size flow reactors were studied.

It was found that the complete decay ( 99% ) of the dichloromethane at 1 second residence time occurs at about 810°C for all the reactants ratio sets. The major products for …


Csma/Cd Lan Performance : Modeling And Simulation In Csim, Nanda K. Kanuri May 1989

Csma/Cd Lan Performance : Modeling And Simulation In Csim, Nanda K. Kanuri

Theses

A simulation model to analyze the performance of CSMA/CD protocol is developed. CSIM, a process oriented simulation language, is used. Performance measures such as throughput, average delay and maximum delay per packet are presented. System performance is analyzed for different loads, number of stations, and network lengths, with packet length as parameter. By trading off the throughput and delay time, an optium packet length can be selected from simulated performance curves. A general scheme for MAC protocols modeling is provided.


A Cmos Robotic Lan Interface Integrated Circuit Design, Yong-Bin Kim May 1989

A Cmos Robotic Lan Interface Integrated Circuit Design, Yong-Bin Kim

Theses

This thesis describes the design including specification, schematics,logic and circuit simulation, and standard cell layout for a CMOS mixed-mode I.C. for interfacing sensors into a robotics local area network. The network accepts up to 256 interface chips as nodes in each area. A simple network protocol permits acquisition of digital data from the interface nodes through gateways into ARCNET and MAP.

The sensor chip interfaces directly from analog signals of range 0-1V and 0-20mV. It contains an 8-bit ADC. The application I.C. interfaces to sensors for pressure, tactile stress, humidity, temperature, etc.

Each of the sensor interface node I.C.s is …


The Rate Of Vibrational Segregation In Particulate Materials, Yidan Lan May 1989

The Rate Of Vibrational Segregation In Particulate Materials, Yidan Lan

Theses

The rate of vibratory size segregation has been modeled in multi-component size systems as a process of mutual sorting between each size species. The concept of mutual sorting is introduced from which generalized expressions are derived for the rates of change of the local concentration of each size species. In a binary system, the expressions simplify to give the expected result that the segregation rates for the large and small particles are equal but of opposite sign. Also, in these systems, the segregation rate is described by measuring the rising speed of the interface between the small and large particles. …


Cascading Lzw Algorithm With Huffman Coding : A Variable To Variable Length Compression Algorithm, Ashish Khandubhai Mehta May 1989

Cascading Lzw Algorithm With Huffman Coding : A Variable To Variable Length Compression Algorithm, Ashish Khandubhai Mehta

Theses

Two common schemes in data compression are fixed to variable length coding and variable to fixed length coding. Higher compression is expected from the more flexible scheme of variable to variable length coding. In such a scheme a compression dictionary is used to transfer variable length string over the text alphabet into variable length strings over the coding alphabet. The compression is achieved due to matching longer more frequent text strings with shorter coding strings.

To obtain a variable to variable length coding we choose to cascade the LZW , variable to fixed , coding with the Huffman , fixed …


Laboratory Model Studies Of Pneumatic Fracturing Of Soils To Remove Volatile Organic Compounds, Panayiotis Papanicolaou May 1989

Laboratory Model Studies Of Pneumatic Fracturing Of Soils To Remove Volatile Organic Compounds, Panayiotis Papanicolaou

Theses

Bench-scale laboratory studies were conducted from January 1988 to October 1988 to demonstrate the feasibility of using Pneumatic Fracturing* to enhance the removal of Volatile Organic Compounds from the vadose soil zone. Experiments were conducted to investigate: 1) The effect of pneumatic fracturing on the rate of contaminant removal; and 2) the injection pressures required to initiate soil fracturing.

Contaminated soil was placed and compacted in three identical 15 inch square by 30 inch high plexiglass tanks. The first tank was equipped with a vapor extraction system consisting of vacuum and/or positive air injection. The second tank was equipped with …