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Analytical Solutions Of Openings Formed By Intersection Of A Cylindrical Shell And An Oblique Nozzle Under Internal Pressure, Hengming Cai

Dissertations

Since several decades ago, many authors have published their research results about local stress distributions of shells and shell-nozzles both analytically and numerically. However, there has not been a published paper, which deals with analytical solutions of cylindrical shell and oblique nozzle, even though in the case of openings formed by intersection of a cylindrical shell and an oblique nozzle.

A comprehensive analytical study of local stress factors at the area of openings formed by intersection of a cylindrical shell and an oblique nozzle under internal pressure is presented in this dissertation.

By means of traditional approach in theory of …

Adaptive Distributed Detection With Applications To Cellular Cdma, Jian-Guo Chen

Dissertations

Chair and Varshney have derived an optimal rule for fusing decisions based on the Bayesian criterion. To implement the rule, probabilities of detection P_D and false alarm P_F for each detector must be known, which is not readily available in practice. This dissertation presents an adaptive fusion model which estimates the P_D and P_F adaptively by a simple counting process. Since reference signals are not given, the decision of a local detector is arbitrated by the fused decision of all the other local detectors. Adaptive algorithms for both equal probable and unequal probable sources, for independent …

Least Space-Time First Scheduling Algorithm : Scheduling Complex Tasks With Hard Deadline On Parallel Machines, Bo-Chao Cheng

Dissertations

Both time constraints and logical correctness are essential to real-time systems and failure to specify and observe a time constraint may result in disaster. Two orthogonal issues arise in the design and analysis of real-time systems: one is the specification of the system, and the semantic model describing the properties of real-time programs; the other is the scheduling and allocation of resources that may be shared by real-time program modules.

The problem of scheduling tasks with precedence and timing constraints onto a set of processors in a way that minimizes maximum tardiness is here considered. A new scheduling heuristic, Least …

Synthesis And Characterization Of Lpcvd Sic Films Using Novel Precursors, Mahalingam Bhaskaran

Dissertations

A unique low pressure chemical vapor deposition (LPCVD) process has been developed to synthesize amorphous and crystalline SiC films using environmentally benign chemicals. The interrelationships governing the process variables, compositions and select properties of the resulting films were established. Such films can be used to produce high quality mask membrane for x-ray lithography. These films can also be used in fabricating high power electrical devices, and hetrojunction devices in conjunction with silicon.

Amorphous SiC films were synthesized using a single precursor, ditertiarybutylsilane, at temperatures below 850°C. Compositional analysis performed on these deposits revealed that, in the deposition temperature range of …

Bilinear Time-Frequency Representations Of Heart Rate Variability And Respiration During Stress, Rindala Saliba

Dissertations

Recently, joint time-frequency signal representation has received considerable attention as a powerful tool for analyzing a variety of signals and systems. In particular, if the frequency content is time varying as in signals of biological origin which often do not comply with the stationarity assumptions, then this approach is quite attractive. In this dissertation, we explore the possibility of better representation of two particular biological signals, namely heart rate variability (HRV) and respiration. We propose the use of time-frequency analysis as a new and innovative approach to examine the physical and mental exertion attributed to exercise. Two studies are used …

Two Dimensional Agonistic Control, Daqing Yang

Dissertations

The conventional method of precise multiple-axis motion control entails use of a multiple axis positioning system with each axis carrying not only the workpiece but also the positioning system of the remaining axes. The resultant structure is heavy, sluggish, and expensive. An alternative positioning technique is being investigated in which the motion of the workpiece is controlled by pulling it with tendons, each of which has its own actuator. Since the actuators can be mounted on the base of the structure instead of being carried by motion system of the other axes, they can be relatively large and powerful without …

Evaluation Of Environmental Characteristics Of Wtp Residuals For Disposal In Monofills, Ping Tian

Dissertations

Disposal of water treatment plant (WTP) have raised great concerns due to the stringent water quality standards and environmental regulations, and limited availability of land for ultimate disposal. The ultimate disposal of water treatment plant residuals by using monofill may be one of the most economical, and feasible options. Design and operation of such a monofill will be simple because of the uniformity of the characteristics of WTP residuals.

The objectives of this project were to determine the environmental characteristics of WTP residuals and to apply these characteristics for the design of monofills and development of the metal leaching model …

Safe Code Transfromations For Speculative Execution In Real-Time Systems, Mohamed Mohamed Younis

Dissertations

Although compiler optimization techniques are standard and successful in non-real-time systems, if naively applied, they can destroy safety guarantees and deadlines in hard real-time systems. For this reason, real-time systems developers have tended to avoid automatic compiler optimization of their code. However, real-time applications in several areas have been growing substantially in size and complexity in recent years. This size and complexity makes it impossible for real-time programmers to write optimal code, and consequently indicates a need for compiler optimization. Recently researchers have developed or modified analyses and transformations to improve performance without degrading worst-case execution times. Moreover, these optimization …

Counterpulsation Cardiac Assist Device Controller Defection Filter Simulation And Canine Experiments, Carl Edward Werner

Dissertations

Electronic control systems for counterpulsation Cardiac Assist Devices (CADs) are an essential part of cardiac assistance. Synchronization of the counterpulsation CAD controller with the cardiac cycle is critical to the efficacy of the CAD. The robustness of counterpulsation CAD controllers varies with the ability of the CAD controller to properly trigger on aortic pressure (Pa) and electrocardiogram (ECG) signals for sinusoid rhythms, non-sinusoid rhythms and non-ideal signals resulting from surgical intervention. An analog-to-digital converter and digital-to-analog converter based CAD controller development platform was devised on a 33Mhz PC-AT.

Counterpulsation Pa systolic rise and dicrotic notch detectors were demonstrated with a …

Non-Linear Evaluation Of Concrete-Filled Steel Tubular Columns, Mohammad Hassan Shams

Dissertations

Concrete-filled steel tubular (CFT) columns have become increasingly popular in structural applications due to their high strength, high ductility, and large energy absorption capacity. These structural properties are the result of integral behavior of the concrete core and the steel tube. This research provides an analysis of the interaction of the concrete core and the steel tube in CFT columns.

While there have been many experimental studies of CFT columns, there has been no analytical work modeling the confining effect of the steel tube on the concrete core. Furthermore, current design procedures tend to underestimate the ultimate strengths of CFTs …

Massively Parallel Reasoning In Transitive Relationship Hierarchies, Yugyung Lee

Dissertations

This research focuses on building a parallel knowledge representation and reasoning system for the purpose of making progress in realizing human-like intelligence. To achieve human-like intelligence, it is necessary to model human reasoning processes by programs. Knowledge in the real world is huge in size, complex in structure, and is also constantly changing even in limited domains. Unfortunately, reasoning algorithms are very often intractable, which means that they are too slow for any practical applications. One technique to deal with this problem is to design special-purpose reasoners. Many past Al systems have worked rather nicely for limited problem sizes, but …

Shaped Charges Having A Porous Tungsten Liner-An Experimental And Theoretical Study Of Metal Compression, Jet Formation And Penetration Mechanics, Brian Edward Fuchs

Dissertations

The use of porous tungsten as a liner for shaped charges to improve their penetration was proposed by Ki-Hwan Oh in his invention disclosure "Shock Extrusion of Ingots from Powders or Solids", at the New Mexico Institute of Mining and Technology, Socorro NM on June 7, 1988. The intention was to increase the ductility of the normally brittle metal by heating the liner to a high temperature by shock compaction during its acceleration just before jet formation.

The feasibility of increasing the ductility of tungsten in this way is the subject of the present study. The theory and prior experimental …

The Computational Study Of "Model" Pollutants In Clay Montmorillonite, Sung-Ho Park

Dissertations

No abstract provided.

Total Quality Management: Bridging Theory To Practice, Richard Ross Brydges Edd

Dissertations

The purpose of this study was to evaluate the practice of Total Quality Management (TQM) in an organizational culture using Deming's System of Profound Knowledge (1993) as a construct that combines the philosophical and methodological dimensions of TQM. As with TeleServices Resources (TSR), the evaluative case study subject for this research, organizations worldwide have adopted TQM to establish a culture that would make them more capable of producing quality products and services. Many of these efforts never realized their potential. My premise for this study is that the potential of their efforts are not fully realized, because organizations do not …

Enter The Water Carriers: Embracing Parenting Experience In Work Teams, Christine Cecil Edd

Dissertations

Parenting experience is rarely valued or integrated with the work of a competitive society such as that of the United States. Despite the implementation of family-friendly workplace policies, institutional structures and practices continue to preclude the substantive acknowledgment of how parenting experience might contribute to the American workplace (Borrill & Kidd, 1994; Jenner, 1994; Rodgers, 1993). The dynamic complexity of parenting and the concomitant necessity to make constant response shifts and navigate incessant uncertainty, is not acknowledged as collateral for the responsiveness required by complex organizations. Familial commitments are often viewed as antithetical to productivity and profit (Bailyn, 1993): babies …

Implementation Of Continuous Quality Improvement In A Community Mental Health Care Center: Effect On Morale, Gary Dean Zomalt Edd

Dissertations

Morale is important to all service organizations because quality is dependent upon the nature of face-to-face interactions. Because the workers in mental health service organizations must care for patients, morale is especially important. Although studies suggest that rapid change due to cutbacks, privatization, and managed care, have demoralized mental health workers, the literature suggests that management is the problem. Mechanistic organizations with top-down, command-control management typically exclude and alienate workers. Continuous quality improvement (CQI) can improve morale as well as the bottom-line. However, there are no studies of how to implement CQI, from the perspective of workers, to improve morale …

Teammind: A Case Study Of Collective Synergism, Team Development, And Decision-Making Under Time Constraints, Norina E. Finley Edd

Dissertations

Advances in technology are challenging our concept of time and cognitive abilities to process and digest information in a dynamic environment. To develop a quality product that meets user's needs and to perform within budget and program milestones, requires the expertise and shared understandings of an intact multidisciplinary team in design decision making. Collaboratively team members need to communicate on solutions for integrated product development, from their different disciplinary perspectives. To survive in today's global competition, time-to-market gives research and development organizations the competitive edge in new product development, using emerging technologies. Therefore, there is a need for qualitative research …

The Relationship Of Teacher Retention To Personality Style At Visionquest National Limited, Beth Ann Rosica

Dissertations

Problem. VisionQuest National Limited is a treatment and education program for court-placed students. Recruiting and retaining quality teachers is a problem faced by VisionQuest administrators. Over the course of a school year, there are usually several teaching-position vacancies, and turnover is high, especially in the first few months of employment.

Method. The Keirsey Temperament Sorter, a derivative of the Myers-Briggs Type Indicator, was administered to all VisionQuest teachers to determine their personality type. The personality types of the VisionQuest teachers were compared to those of teachers in the general population. Length of employment of VisionQuest teachers was also analyzed in …

No Longer An Alien, The English Jew: The Nineteenth-Century Jewish Reader And Literary Representations Of The Jew In The Works Of Benjamin Disraeli, Matthew Arnold, And George Eliot, Mary A. Linderman

Dissertations

No abstract provided.

Leadership From The Perspectives Of Filipino-Americans: A Delphi Study, Pablo J. Mendoza Edd

Dissertations

The majority of the texts and other materials on leadership have been written from the perspective of people from Western culture. A number of scholars have called attention to this lack of a more diverse literature, inquiring as to the reasons why academicians primarily offer leadership literature that has a predominantly Western culture perspective. Since social and political contexts represent diverse cultural views, leadership literature should also reflect that diversity. This issue is particularly important in the San Diego area for Filipino-Americans because of their increasing numbers and active participation in social and political endeavors. The absence of culturally and …

Selected Roles/Functions Of Technical/Vocational Education Administrators In Barbados And The Need For Further Preparation And Continuing Professional Development, Cecil I. Cummins

Dissertations

The purpose of this study was to identify the roles/functions of technical/vocational education (TVE) administrators in Barbados and to ascertain their personal needs for further preparation and continuing professional development.

The population for the study consisted of 115 TVE administrators from the Ministry of Education, tertiary institutions, vocational centers, Grammar schools, and Newer secondary schools. The survey method was used to gather the data. All respondents were asked to complete a 87-item questionnaire which described various roles/functions associated with the administration of TVE programs under eight major categories. For each role descriptor, respondents were asked to indicate how important it …

Interleukin-2 Activated Lymphocytes Use Cd11b/Cd18 For Adhesion To Candida Albicans, Christopher B. Forsyth

Dissertations

No abstract provided.

Structure-Function Analysis Of The Catalytic Domain Of The Histidine Kinase Chea, Dolph David Ellefson

Dissertations

No abstract provided.

Global Training And Education: An Examination Of Context, Cultural Toughness, And Minimum Necessary Change In Internationally Diverse Organizational Settings, Leslie E. Dennis

Dissertations

No abstract provided.

Concerns Of First-Year Teachers In Selected Public Schools, Delores A. Price

Dissertations

No abstract provided.

Social Support, Self-Efficacy And Their Relationship To The Academic Performance Of African-American Students Attending An Historically Black University, Torrey Wilson

Dissertations

No abstract provided.

Testing A Model Of Degree Progress Among African-American Graduate Students, Mary F. Toliver

Dissertations

No abstract provided.

An Investigation Of Development Policies Related To The Establishment Of Endowed Chairs At Research I And Ii Universities, Mary K. Mclaughlin

Dissertations

No abstract provided.

Student Culture At Wheaton College: Understanding Student Life On An Evangelical Christian College Campus, Kevin D. Cumings

Dissertations

No abstract provided.

A Comparative Analysis And Evaluation Of Knowledge Structures Between Expert Novice And Struggling Novice Accounting Students, Michael L. Carroll

Dissertations

No abstract provided.