Digital Commons Network^™

Frequency Modulated Pulse For Ultrasonic B-Scan Imaging In Attenuating Medium, Sumat Mehra

Theses

A rigorous study of a new technique for Ultrasonic B-Scan imaging was performed. This technique made use of a Frequency Modulated (FM) pulse as opposed to the conventional Short pulse for imaging. The simulation studies offered sufficient support for this method, which was then implemented in the laboratory. Experiments were performed on phantoms which mimicked the attenuating medium. Due to the more flexible nature of this FM pulse, changes in the point spread function were studied as a function of bandwidth and depth of the scatterer. The backscattered signal was digitized post processed, and then displayed as a gray-scale B-scan …

Microwave Treatment Of Hazardous Wastes : Chemical Fixation Of Insoluble Non-Volatile, Chemically Non-Reactive Organics In Soil, Naihong Zhu

Theses

Microwave treatment of hazardous wastes like dioxin-contaminated soil potentially fills a great need for a remediation technology which potentially can be applied in-situ: the EPA has concluded from a risk assessment study that it is the excavation and transportation of such wastes that poses the greatest risk. Studies have been carried out on a surrogate for dioxin, namely, 9,10-anthraquinone because it has similar chemical and physical properties but it is not toxic. It was found in microwave treatment studies that, at temperatures attainable in-situ, anthraquinone became non-extractable. A model was proposed which postulated that as water was removed from soil …

A Conceptual Look At Hodgkin's Disease, Todd K. Smith

Theses

None provided.

Negative Feedback Control Of The Visual System And Systematic Color Vision Model, Yan Liu

Theses

This thesis presents a physiological hypothesis of a systematic negative feedback control mechanism of the human visual system and a corresponding systematic color vision model. This model is based on the physiological hypothesis of systematic negative-feedback control of the visual system and both the stage color vision theory and Land's theory. According to this systematic color vision model, the color vision is processed as described by the stage theory, the negative feedback of the visual system adjusts the sensitivities of the cone photoreceptors and controls the visual system to adapt to the visual surroundings . The dynamic ranges of relative …

A Study Of Biological Dentrification Of Munition Wastes, Sonia R. Venugopal

Theses

Kinetics of denitrification were studied using a consortium from the Lawrence, Kansas municipal treatment plant. Experiments were conducted in the batch mode, under controlled oxygen and pH conditions. It was found that the Monod model can successfully perdict the experimental results of nitrate depletion. It was also found that when the pH is maintained at values between 7.0 and 8.5, nitrate can be treated in a batch mode without having any significant nitrite presence in the reactor. The experimentally determined kinetic parameters were used in preliminary calculations for sizing a sequencing batch reactor (SBR). An existing mathematical model for the …

Coexistence Of Three Pure And Simple Competitors In Four Interconnected Bioreactors, Ming Wu

Theses

It is known that a homogeneous environment having invariant inputs cannot allow for steady state coexistence of any number of pure and simple competitors. However, it has been proven that two pure and simple competitors can coexist at a steady state in two interconnected chemostats, if the conditions are such that they allow a different species to grow faster in each one of the two vessels. It has been also shown that three pure and simple competitors cannot coexist in three interconnected chemostats, even if the conditions are such that a different population could grow faster (have the competitive advantage) …

Analysis Of Chemical Contaminants In Tissue Samples From Two Species Of Fish, Michael David Reive

Theses

Interaction of marine species with chemical pollutants within the marine ecosystem is extremely complex and difficult to interpret. The purpose of this thesis was to investigate the effect of an exposure of treated municipal wastewater on winter flounder (Pseudopleuronectes americanus) and striped bass (Morone saxatilis). Fish from two locations were exposed to different concentrations of wastewater. Half of the fish from each tank were sacrificed, and the remaining fish were given a depuration period in unpolluted water. Tissue samples were composited, soxhlet extracted and passed through a florisil cleanup column. Gas chromatography, was used to analyze for hexachlorobenzene, hexachlorobutadiene, Aroclor …

Centrifugal Modeling Of Leaking Underground Storage Tanks, Kuo-Neng George Chang

Theses

There are between 2 to 3.5 million Underground Storage Tanks (UST) located through this nation. Most of these tanks store gasoline and fuel oil. Many tanks in fact are or will soon be leaking, thus making them one of the major sources of groundwater contamination in USA. The fate and transport of chemicals from the leaking USTs is estimated from mathematical models. A major difficulty in these modeling efforts has been a crucial lack of information concerning the constitutive relationships governing multiphase contaminant movement.

Centrifugal modeling is an alternative to mathematical modeling, which may give an insight to the problem …

Multiresolution Techniques : Laplacian Pyramid Coding And Its Comparison With Subband Coding, Danmei Chang

Theses

The multiresolution pyramid and related structures have been developed as intermediate representations between the purely frequency domain and purely spatial domain. In this thesis. we discuss two important pyramid structures which are often used in multiresolution representation: Laplacian pyramid and subband coding.

Laplacian pyramid. a typical pyramid structure, is studied in detail. By means of software implementation. we obtain a comprehensive understanding of its features and applications in image representation and data compression. Several modifications of pyramid structure are used to compress the data dynamic range, reduce the computational complexity and improve performance. Performance of the conventional Laplacian pyramid and …

Thermal Desorption Of Organic Contaminant From Sand Using A Continuous Feed Rotary Kiln, Hsien-Tsung Chern

Theses

The purpose of this research was to determine the feasibility of removing organic contaminants from sand by thermal desorption. A continuous feed rotary kiln was designed and constructed to study the thermal desorption behavior of organic contaminant from sand with respect to temperature and residence time, and to develop a mathematical model that will describe this desorption behavior. The model will allow prediction of the desorption rate of an organic contaminant in larger scale rotary kiln desorption system over temperature at a known set of residence time.

In this experiment, sand was uniformly contaminated with a known amount of organic …

Development Of Techniques Of Artificial Intelligence In Identifying The Different Machined Surfaces, Yi-Ching Chou

Theses

This thesis deals with the identification of different machined surfaces with artificial inteligence techniques. There are five kinds of machining operations: grinding, turning, milling, EDM and waterjet which determine the characteristics of resulting surfaces. Topology of various specimens is measured using the surfanylizer. Twenty one parameters are extracted from the measurements to describe the characteristics. In this thesis, we develop neural and expert systems that recoginize and classify surfaces according to the machining methods.

Anaerobic Biological Treatment Of Incinerator Ash To Immobilize Toxic Metal Residues, Uma Parasar

Theses

In this study, a reliable and inexpensive method for biologically immobilizing toxic heavy metal residues present in very high concentrations in incinerator ash was developed. Desulfovibrzo, a genus of sulfate-reducing bacteria was cultured and treated with combined ash under anaerobic conditions. The carbon source, lactate, and the electron acceptor, sulfate, were provided to the cultures for their normal growth. Since the sulfate reducers utilize organic matter using sulfate as the oxidizing agent, sulfides are the corresponding end products of the reaction. Ash was added to well established cultures of desu f ovibrio. Immobilization of the heavy metals in the ash …

Thermal Desorption Of Contaminated Soils, Hsi-Ming Sung

Theses

A new method by employing the heating probe for the in-situ cleanup of soils that are contaminated with volatile organic hazardous substances is explored. This investigation is a laboratory simulation that was aimed to evaluate the feasibility of desorption of volatile organic compoumds (VOCs) from soil, and to determine the efficiency of the heating probe for maximum desorption.

Two organic compounds, Trichloroethylene, Carbon tetrachloride, were selected as simulants. The experimental results demonstrate that the removal efficiency range from 97.65% to >99.95% of Trichloroethylene and 98.14% to >99.95% of Carbon tetrachloride can be recovered for a 24 hour interval with a …

The Application Of Feedback And Control System Theory To Organizational Modeling, Thomas Miklos Tamas

Theses

A review of the literature showed that relatively little attention has been given to the application of feedback and control systems to management. Since a major function of management is control, scientific management might offer assistance in the form of a more quantitative approach to management control. This thesis suggests one might accomplish this through the application of feedback and control systems.

The application of feedback and control theory to management systems is relatively new, however, literature has shown a trend towards the application of electrical engineering theory to non-engineering topics [Khranovich76]. There has also been some research in the …

Efficient Multiprocessor Scheduling By Mean Field Theory Neural Networks, Pei-Ken Yi

Theses

In this thesis, we develop an optimization method based on Mean Field Theory (MFT) Neural Networks to solve the Task Scheduling problem. The MFT algorithm combines characteristics of the Simulated Annealing (SA) algorithm and the Hopfield neural network. MFT exhibits rapid convergence and at the same time it preserves the solution quality afforded by SA. Since MFT has been successfully used to solve the Traveling Salesman Problem (TSP), a new modification to MFT is also presented which supports Task Scheduling problem. The temperature behavior of MFT during Task Scheduling is approximately analyzed and shown to possess a critical temperature (71,) …

Solid-Liquid Suspension In Agitated Vessels Provided With Multiple Impellers, Tong Li

Theses

A large number of references can be found in the literature on the effect of mixing parameters on the achievement of the minimum agitation speed to just suspend solid particles. In the vast majority of these studies the agitation system consisted of just one centrally mounted impeller. However, the determination of the minimum agitation speed to achieve the just suspended state when the additional impellers are used have received very little attention. It is the intent of this work to investigate the role of multiple impeller agitation system on the achievement of the complete particle suspension state. The effect of …

Deposition Of Particles In A Channel With Gravity And Image Forces, Jing-Shiun Lai

Theses

Deposition of particles in a parallel-plate channel under the influence of inertia, fluid viscosity, gravity and image forces was studied using trajectory method.

A laminar fluid flow of uniform and parabolic (or fully-developed) velocity profiles is assumed and the fluid is suspended with particles having the same velocity as the fluid at the inlet plane. The particles flowing into a horizontal parallel-plate channel have no initial velocity in the vertical direction. The influence of gravity force and image force produces a vertical motion which results in deposition of particles on the channel walls.

A trajectory method was employed to find …

Metamorphosis, Ching-Yuan Chang

Theses

None provided.

A Descriptive Study On Trekking Attributes In Nepal Using Importance-Performance Analysis, Pasi Ryhanen

Theses

Since the opening of its doors to the outside world, Nepal has seen a large growth in tourist arrivals. One of the fast growing tourist markets attracted to Nepal is the trekking vacationers. In order for the suppliers and decision makers of the trekking product to be able to meet the demand of users it is important that they are able to target the development in the appropriate direction. A lack of communication among the components of the tourism industry has resulted in a lack of cooperation. The purpose of this study is to develop an instrument that enhances communication …

Options And Limits In A Woman's World, Teresa A. Davis

Theses

This is a study of women who are ascribed the role of mother, but who would also like to pursue a satisfying career. These women experience multiple demands when trying to fulfill these multiple roles. The study focused on how women integrate motherhood and employment. The methodology employed in this study was qualitative. Information was solicited through the use of informal personal interviews conducted by the researcher. A single hour interview was conducted with each participant in the research project. The sample consisted of 10 full - time working mothers who volunteered to participate in the project.

The purpose of …

Ms. Pacrat: A Feeling, Thinking Machine, Lorraine D'Ortona

Theses

Since before the time of the first digital computers, the workings of the mind have been compared to that of a machine. With the onset of the discipline of Artificial Intelligence a truly organized attempt has been made to build intelligent machines that model the mind. Many interesting programs have been built, but the legitimacy of their success is a matter of great controversy. None of the AI programs developed so far have come close to the true power and intelligence of the brain. Expert systems, for example, are the most success ful commercial AI programs, and even they have …

The Level And Extent Of The Need For Workshops To Be Presented On Alcohol And Substance Abuse From The Black Cultural Prospective, Amelia I.G. Massie

Theses

The purpose of this research was to identify and assess the level of alcohol and substance abuse among the elderly. The primary focus was on the Black Elderly Community. The The secondary purpose was to determine the importance of an alcohol and substance abuse workshop for the Black Elderly Community.

The results suggested that a workshop was indeed needed for the Black Elderly Community. A workshop was designed using the data collected from the research.

A Relationship Between Birth-Order Position And The Incidence Of Eating Disorders, Mary Weber

Theses

Eating disorders, bulimia, anorexia, and compulsive eating are a rising concern for the female population as they currently affect women in almost epidemic proportions. Research has enabled us to categorize like-characteristics among those clients who are affected as well as, to develop with some consistency, portraits of the family systems in which these patients develop their symptoms.

A key factor in the family structure is the role that each sibling assumes, which is often directly influenced by the ordinal position of their birth in relationship to their siblings. Research has also identified a categorical profile of characteristics associated with each …

Adjusting Property Values For Power Lines: An Exploratory Study, Robert T. Hirst

Theses

For thirty years researchers warned of potential danger,3 oi electromagnetic fields ( EXF) near electrical power lines and substations. The Environmental Protection Agency is presently reviewing the research to date to see if a substantial health hazard from EMFs threaten public health.

The Appraiser studied two subdivisions built 1985- 87 in Brentwood, Tennessee to see if EMF publicity stigmatized 6 homes adjoining TVA transmission lines right of way (AT) by decreasing expected s ales price compared to 44 homes not adjoining right of way (NAT).

In this small sample of convenience (6 AT subjects), two sold before 1989 at a …

The Effect Of Psychosocial Factors On The Immune Response Of Hiv Infected Individuals As Measured By The Extent Of Relationship With Cd-4 T Cell Count And Physical Symptoms, Richard R. Taylor

Theses

The effect of psychosocial factors on the immune response of HIV infected human subjects was assessed by measuring the degree of relationship to CD-4 T cell count and physical symptoms.

Twenty six participants (22 white and 2 black males) all who had been diagnosed as HIV positive completed a battery of 11 psychological tests and a social and medical history questionnaire. Fifty four psychosocial factors were selected as having the potential to have a significant effect on immune response.

Correlational analyses yielded no strong relationships between the psychosocial factors and CD-4 T cell count or physical symptoms. Moderate associations were …

The Family Dance Model: A Definition And Comparison With The Beavers, Olson, And Mcmaster Models Of Family Functioning, Lyle V. Turnage

Theses

This study explored the hypothesis that married couples have ways of relating to each other which are peculiar to their relationship; and that other couples operate under the same or similar patterns of relating.

"Patterns in family relationships are often referred to as dances." (Lerner, 1990). Dances are determined by the music played, the manner of dress or costume, physical movements, and the tempo or beat (Chujoy & Manchester, 1967). Family dances are also recognized by physical interactions or movements, appearance or dress, and the beat of family messages. The family dance model will use names of dances such as …

Assessing How The Catholic Church (At The Parish Level) Meets The Needs Of The Frail, Elderly, And Handicapped In The St. Louis Archdiocese, Joann C. Hermann

Theses

All Catholic churches of the St. Louis Archd1ocese were the focus of a study conducted to examine how the church meets the needs of the frail, elderly, and handicapped on the parish level. A total of 227 parishes were included 1n the survey; of these 138 responded to the questionnaire. A significant relationship between income of the parish and physical structural improvements to accommodate the frail, elderly and/or handicapped was not indicated. A significant difference between the number of male and female volunteers was not found. However, there were significant findings to support the hypothesis that Pastors and the Catholic …

Management Decision Making And Political Viability Criteria In Large Corporate Organizations, Kalman J. Kovach

Theses

This thesis focuses on the magnitude of political viability in managerial decision making in large corporate organizations . Political viability ls defined as perpetuating shrewdness to flourish one's career within an organization.

Recent economic conditions and global competitiveness have forced corporations to examine their traditional managerial roles. As a result, many corporations have totally revamped goals and objectives in an attempt to present a clear and unobstructed vision of their mission.

Over the last decade research done by organizational psychologists, consultants, independent ·think· tanks, and decision experts have bombasted corporations with many management philosophies . Decision making is an integral …

Conservation Survey Of The Benaki Museum Photographic Archive In Athens, Greece, Vasiliki Hontos

Theses

Not listed.

Effect Of Low Level Radiation On The Barrier Qualities Of Spunbonded Olefin, Samir A. Sheth

Theses

Medical packages have to meet highly specific criteria over and above other types of packages. Protection of contents from microbial contamination and physical damage is a priority. The permeability to sterilizing gas; retention of properties and appearance after sterilizing radiation; printability and aseptic presentation all have to be present at reasonable cost. The most important is maintenance of sterile integrity. In order to have sterile integrity, the medical package must have high barrier properties. Sterility maintenance is the ability of porous packaging materials to act as barriers to microorganisms. The random non- woven structure of spunbonded olefin creates a highly …