Digital Commons Network^™

Analysis Of The Optimum Extraction System Design For The Separation And Purification Of Rare Earths, Kenneth Yeon-Kang Chan

Dissertations

A mathematical model for the liquid-liquid equilibrium of the lanthanide and yttrium oxides in the nitric acid - water - tributyl phosphate (HNO₃-H₂O-TBP) two-phase system has been developed. This model is based on the interrelationships of chemical reactions, phase equilibrium, and material balance. The chemical reactions were modelled using experimentally derived empirical equations for components involved. The distribution coefficients of 16 rare earths which were experimentally determined. by UK Harwell Laboratory were used to evaluate the parameters of this equilibrium model. Once model parameters are determined, material balance for all species in the HNO₃-H …

Kinematic Synthesis Of Adjustable Four-Bar Mechanisms For Multi-Phase Motion Generation, Shao Jie Wang

Dissertations

A four-bar linkage can satisfy up to five prescribed positions for the motion generation problem. The adjustable four-bar linkage, on the other hand, can satisfy more than five given positions by making some of the parameters adjustable.

Limited work had been done in the area of motion generation problems of kinematic synthesis of adjustable four-bar linkages until Wilhelm introduced the concept of multiple adjustments.

This study considers for the first time, the adjustment of a moving pivot, and the problems of three phases of motion. Various combinations of the number of prescribed positions for the motion generation problems are solved …

Study Of Surface Properties Produced By Magneto-Plasma On Nitriding For Improving Wear Resistance, I-Tsung Shih

Dissertations

In this work a newly developed surface treatment process, Magneto-Plasma Ion Nitriding process, was developed and studied. This process was developed to increase durability and wear resistance of operational surfaces of different machine components.

In this study, orthogonal experimental analysis was used to develop, optimize, and select the process parameters. Coating layers were characterized and studied by using scanning electron microscopy(SEM), Auger electron spectroscopy(AES), and image analysis system. The influence of different process treatment parameters, such as temperature, nitrogen concentration, and magnetization, on the layers properties was studied. The mechanism of layer formation and bonding was proposed and a mathematical …

Investigation Of The Striation Formation In The Course Of Abrasive Waterjet Cutting, Jo-Fei Chao

Dissertations

The principal defect of the surfaces generated by abrasive waterjet machining is excessive waviness (striation). The existing theories of striation formation are not adequate to explain this phenomenon. The presented study is concerned with the development of an understanding of the mechanism of striation formation.

A spectral analysis of temporal process and spatial surface characteristics demonstrated that the striation is caused by nozzle vibration that is due to the conditions of the motion control of the nozzle. This enabled us to discover a means for improving the surface finish. From a study of the surface spectra, it was found that …

Investigation Of The Consumer Electronics Bus, Jaesoo Yang

Dissertations

The objectives of this dissertation are to investigate the performance of the Consumer Electronics Bus (CEBus) and to develop a theoretical formulation of the Carrier Sense Multiple Access with Contention Detection and Contention Resolution (CSMA/CDCR) with three priority classes protocol utilized by the CEBus

A new priority channel assigned multiple access with embedded priority resolution (PAMA/PR) theoretical model is formulated. It incorporates the main features of the CEBus with three priority classes. The analytical results for throughput and delay obtained by this formulation were compared to simulation experiments. A close agreement has been found thus validated both theory and simulation …

On Adaptive Censored Cfar Detection, Loizos Anastasiou Prastitis

Dissertations

In an automatic radar detection system the received signal in every range resolution cell is compared with a threshold to test for the presence of a target. A Neyman-Pearson type test is used which maximizes the probability of detection for a fixed probability of false alarm. For the simple case where the noise is homogeneous a fixed threshold is chosen to achieve the designed constant false alarm rate (CFAR). In the more realistic case the noise background is non-stationary due to clutter and interference. In this situation, the threshold used for testing a particular cell is usually set adaptively using …

Investigation Of Reactor Design Parameters Towards Optimizing Biodegradation Of Chlorophenols By Phanerochaete Chrysosporium, Nirupam Pal

Dissertations

The biodegradation of 2,4,6-trichlorophenol (246-TCP) and 2,4,5-trichiorophenol (245-TCP) by Phanerochaete chrysosporium was studied in batch and in continuous systems. Contrary to most of the previous reports from the literature, this study shows that degradation of both TCPs can occur in the absence of any measurable ligninase activity. The microorganism did not retain its degradative ability for more than about two weeks

In order to better understand the degradation process, the individual contributions of both the biomass and the extracellular proteins were studied separately. The results show that neither the biomass nor the extracellular proteins alone can completely degrade 246-TCP, but …

The Evolving Role Of Research In Mexican Graduate Programs In The Field Of Education: A Case Study Of Six Selected Programs (1980-1992), Romay Maria De La Luz Munoz

Dissertations

No abstract provided.

An Analysis Of Collective Bargaining Based On The Win-Win Philosophy Of Conflict Resolution Used By Six Selected Chicago Suburban School Districts, Gaetana Lynn Calabrese Mollin

Dissertations

No abstract provided.

Cocaine Dependence: Causal Attributions For Real And Hypothetical Relapse, James W. Pier

Dissertations

No abstract provided.

The Teacher Efficacy Construct And Its Relationship To Attributional Dimensions (Causal Attributions) And Attributional Style, Charlene Marie Hopp Conarty

Dissertations

No abstract provided.

A Study Of The Induction Needs Of Novice Teachers As Perceived By Central Office Administrators And As Perceived By Students In Their Last Year Of Teacher Training As Compared To Novice Teachers' Induction Needs Identified From A Synthesis Of The Literature On New Teacher Induction, Mary Ellen Burke

Dissertations

No abstract provided.

The Development Of The Home And Hospital Program Of The Chicago Public Schools, 1899-1985, Vivian E. Rankin

Dissertations

No abstract provided.

Bicultural Women In Monocultural Organizations: Professional Hispanic Women's Experiences Of Diversity And Their Recommendations For Organizations, Carmen Mestas Bárcena Edd

Dissertations

The composition of the work force in this country is changing from one in which the White male was dominant to one in which by the year 2000 women and ethnic minorities will be dominant. Work force diversity will impact organizations at all levels, including top management, which has been closed to women and minorities, and in particular, minority women. The diverse work force's expectation for advancement into top levels of management will present challenges to organizations. Some organizations have recognized that to remain competitive they need to manage a more diverse work force. The purpose of this study is …

District Elections, Redistricting And Recall: A Study Of The Fifth District Of The City Of San Diego, 1988-1991, Linell Blair Fromm Edd

Dissertations

In 1988, voters in San Diego approved a switch from an at-large to a district-only election system. In 1989, Linda Bernhardt, a 30-year-old political neophyte, ran an anti-developer, grassroots campaign in San Diego's Fifth Council District. She unseated well-financed, two-term, pro-development incumbent Ed Struiksma. Within 17 months, Bernhardt was recalled from office. It was the first successful recall election in the City of San Diego in the twentieth century. This study documented significant events that bore on Bernhardt's recall to gain an understanding and appreciation of how events necessitated the recall. The researcher analyzed contributing factors, using an historical case-study …

Empowerment As A Dynamic Of The Leadership Relationship: A Study Of Two Local Governmental Organizations, Danell Scarborough Gavares Edd

Dissertations

The purpose of this study is to develop a better understanding of the empowerment processes operating within organizations and to theorize about the relationship between empowerment and leadership. The study focuses on empowerment in two local governmental organizations--the City of Carlsbad, California and the City of Scottsdale, Arizona. The research design combined the key characteristics of naturalistic inquiry with the analytical approach of grounded theory methodology. The researcher interviewed the members of both management teams and spent time as a participant observer. The data were synthesized into a conceptual model--a picture of the empowerment practices within these two organizations. The …

An Evaluation Study Of The Effects Of The Pirk Reading Program On Reading And Learning Development In Learning-Disabled Students, Ethelyn Elliott Shippey Edd

Dissertations

An emerging view on learning disabilities is that failure in learning to read in the early grades results in continuing failure in school, along with cognitive and social/emotional dysfunctions: Educational leaders have called for reading programs that are maximally effective and minimally time-consuming, and are suited to the needs of our particular students. Leaders in the field of special education stressed a need for the prevention of failure. This evaluation study examined how the PIRK reading program components fit with the current literature on teaching reading and language arts to all children and to LD children. This study investigated the …

The Effect Of Reading And Discussing Literature With Strong Women Characters On Sixth Grade Students’ Sex Stereotype And Occupational Attitudes, Leslie Caspi Edd

Dissertations

There is considerable evidence that children develop stereotyped attitudes early in life and that these attitudes affect their futures. Many researchers agree that children's attitudes can be influenced by what they read and some studies have shown that attitudes can be changed by exposure to selected literature. This study focused on a group of sixth grade children reading selected short stories and novels with female main characters. Literature discussion groups and written journals were used to facilitate response. The clays was racially and socioeconomically mixed as a result of busing through the Voluntary Ethnic Enrollment and Magnet Programs. The class …

Identification Of The At-Risk Mathematics Student Within The Community College Environment, Gerry Lee Cox

Dissertations

Problem. This study sought to develop a tool to identify the nonsuccessful, at-risk community-college student for correct placement, monitoring, and retention. A comparison in academic achievement of at-risk, remediated students with nonremedial students in a first college-level mathematics class (Intermediate Algebra 101) was also studied.

Method. The ex post facto study sought to determine to what extent the successful and nonsuccessful at-risk mathematics students (n = 358) differ on ASSET test scores, criterion referenced pretest scores, mathematics attitude scores, attendance profile, race, gender, and demographic variables. Statistical analyses using descriptive procedures, ANOVA, MANOVA, Chi-square, and discriminant analysis were used with …

Apostolic Succession In The Writings Of Yves Congar And Oscar Cullmann, Carlos Alfredo Steger

Dissertations

Since its first explicit enunciation by the end of the second century, apostolic succession has been considered as one of the basic components of the church's apostolicity. As history shows, however, there have been different views on the nature and function of apostolic succession. Moreover, its legitimacy and normativeness have been challenged, particularly since the sixteenth century onwards. In our century, fairly established confessional positions have been reexamined in the light of new theological perspectives, as is evident in the documents produced by the ecumenical movement.

The purpose of this research was to set forth, analyze, compare, and evaluate Yves …

William Clarence (W. C.) White: His Relationship To Ellen G. White And Her Work, Jerry Moon

Dissertations

The topic. William Clarence White (1854-1937), third son of Seventh-day Adventist founders James and Ellen G. White, was for thirty-four years his mother's counselor, editor, and spokesman. He was alleged by some to stand in a manipulative relationship to his mother and her work, a charge she denied.

The purpose. The purpose of the study was to describe, analyze, and evaluate W. C. White's relationship to his mother and her work during her lifetime. This purpose required the development of a partial biographical sketch of W. C. White as a context for understanding his relationship to his mother.

The sources. …

Compliance With Selected Educational Policies In The Archdiocese Of Milwaukee Catholic Elementary School System, Thomas C. Martin

Dissertations

No abstract provided.

A Comparative Analysis Of The Principal Selection Process In Catholic And Non-Catholic Christian Elementary Schools In The Chicagoland Area, Timothy J. Reilly

Dissertations

No abstract provided.

Roles Of Ion Channels In Nervous System Tumor Cell Growth, Yong Soo Lee

Dissertations

No abstract provided.

Channels Of Imperishable Fire: The Christian Mystical Allegories Of Dioscorus Of Aphrodito, Clement A. Kuehn

Dissertations

No abstract provided.

Faculty Perceptions Of The Role Of Department Chairperson In Facilitating Tenure Acquisition, Frances Daly

Dissertations

No abstract provided.

The Dunne School Board : Reform In Chicago, 1905-1908, Mary Schiltz

Dissertations

No abstract provided.

The Teacher Efficacy Construct And Its Relationship To Attributional Dimensions (Causal Attributions) And Attributional Style, Conarty Charlene Marie Hopp

Dissertations

No abstract provided.

A Framework Of Transformational Leadership Concepts Proposed For Undergraduate College And University Student Development And Student Affairs Leadership Programs, Stanley D. Fasci Edd

Dissertations

Educating undergraduate students in the area of leadership has long been part of the educational mission of many public and private institutions of higher education in the United States. At many of these colleges and universities, leadership education and training has been accomplished by programs directed by student development or student affairs divisions of the institution. The purpose of this study was to identify a framework of transformational leadership concepts that could be integrated into existing student development/affairs leadership programs. The study's objectives were: (1) to obtain expert opinion regarding transformational leadership concepts to be used; (2) to verify whether …

Descriptive Case Studies Of Training, Research And Development In Computers And Related Instructional Technologies For Teachers At Three Ncate Universities, Anne L. Chandler

Dissertations

Topic. The initial focus of this study was the computer and related instructional technology training of preservice teachers. Two areas related to the study, (1) graduate-level instruction in computers and related instructional technologies and (2) research and development in the area of computers in instruction, were also surveyed, with the intent of exploring their relationship to the training of preservice teachers and their influence on instruction in general.

Purpose. The purpose of this study was to describe training, research, and development in computers and related instructional technologies at three NCATE universities which were identified as doing a good job of …