Digital Commons Network^™

Towards Designing A Knowledge-Based Tutoring System : Sql-Tutor As An Example, Gang Zhou

Dissertations

A Knowledge-Based Tutoring System, also sometimes called an Intelligent Tutoring System, is a computer based instructional system that uses artificial intelligence techniques to help people learn some subject. The goal of the system is to provide private tutoring to its students based on their different backgrounds, requests, and interests. The system knows what subject materials it should teach, when and how to teach them, and can diagnose the mistakes made by the students and help them correct the mistakes.

The major objective of this dissertation is to investigate and develop a generic framework upon which we can build a Knowledge-Based …

Emulsion Liquid Membrane Removal Of Arsenic And Strontium From Wastewater : An Experimental And Theoretical Study, Ding-Wei Zhou

Dissertations

The emulsion liquid membrane (ELM) technique has been successfully applied on the removal of arsenic (As) from metallurgical wastewater and the removal of strontium (Sr) horn radioactive wastewater. This study consisted of experimental work and mathematical modeling.

Extraction of arsenic by an emulsion liquid membrane was firstly investigated. The liquid membrane used was composed of 2-ethylhexyl alcohol (2EHA) as the extractant, ECA436OJ as the surfactant, and Exxsol D-8O solvent (or heptane) the diluent. The sulfuric acid and sodium hydroxide solutions were use I as the external and internal phases, respectively. The arsenic removal efficiency reached 92% within 15 minutes in …

Explicit Congestion Control Algorithms For Available Bit Rate Services In Asynchronous Transfer Mode Networks, Ambalavanar Arulambalam

Dissertations

Congestion control of available bit rate (ABR) services in asynchronous transfer mode (ATM) networks has been the recent focus of the ATM Forum. The focus of this dissertation is to study the impact of queueing disciplines on ABR service congestion control, and to develop an explicit rate control algorithm.

Two queueing disciplines, namely, First-In-First-Out (FIFO) and per-VC (virtual connection) queueing, are examined. Performance in terms of fairness, throughput, cell loss rate, buffer size and network utilization are benchmarked via extensive simulations. Implementation complexity analysis and trade-offs associated with each queueing implementation are addressed. Contrary to the common belief, our investigation …

Design, Process And Performance Simulation Of A 360x360-Element Very High Frame Rate Burst-Image Sensor, Guang Yang

Dissertations

A process was developed for fabrication of 360x360-element Very High Frame Rate (VHFR) burst-image sensor on the bases of one-dimensional (1-D) and two-dimensional (2-D) device and process simulations using SUPREM III, SUPREM IV, PISCES IIB and ISE-TCAD software, and the process data provided by the David Sarnoff Research Center. This process includes SiO₂-Si₃N₄ gate dielectric, four-levels of polysilicon, three-levels of metal, eight implants, and requires twenty-one mask levels. The imagers with a 2-cmx2-cm chip size were fabricated at the David Sarnoff Research Center. The VHFR burst-image sensor is capable of capturing images at frame rates …

Pattern Discovery In Sequence Databases : Algorithms And Applications To Dna/Protein Classification, Gung-Wei Chirn

Dissertations

Sequence databases comprise sequence data, which are linear structural descriptions of many natural entities. Approximate pattern discovery in a sequence database can lead to important conclusions or prediction of new phenomena. Traditional database technology is not suitable for accomplishing the task, and new techniques need to be developed.

In this dissertation, we propose several new techniques for discovering patterns in sequence databases. Our techniques incorporate pattern matching algorithms and novel heuristics for discovery and optimization. Experimental results of applying the techniques to both generated data and DNA/proteins show the effectiveness of the proposed techniques.

We then develop several classifiers using …

Global Fuzzy Control Based On Cell Mapping, Tea-Quin Kim

Dissertations

Cell mapping methods can generate global optimal controls for nonlinear dynamic systems. However, the implementation of this approach for on-line control is difficult due to its use of a table-based controller which requires a large amount of memory.

In this dissertation, a cell mapping based systematic method is developed to construct a fuzzy controller to replace the table-based controller for global optimal control of dynamic systems. The method consists of four steps: 1) An optimal control table is generated using a cell mapping algorithm. 2) The cells are linked into trajectories to characterize the optimal dynamic evolution of various cell. …

Development Of A Traffic Safety Index For Urban Intersections, Jae-Hong Kang

Dissertations

Conventional safety analysis focuses on the accident environment at specific locations or a limited segment of highways or arterials, and attempts to identify the effects of accident contributing factors. The development of a safety index in the past was based on a statistical summary for county or statewide areas, using general indicators such as population, number of registered vehicles, vehicle miles traveled and so on. This research effort presents a state-of-the-art procedural analytical approach for the safety analysis of Manhattan intersections that are exposed to a unique urban environment. The computed index provides safety ratings that can identify potential safety …

Knowledge Discovering For Document Classification Using Tree Matching In Texpros, Ching-Song Wei

Dissertations

This dissertation describes a knowledge-based system for classifying documents based upon the layout structure and conceptual information extracted from the content of the document. The spatial elements in a document are laid out in rectangular blocks which are represented by nodes in an ordered labelled tree, called the "layout structure tree" (L-S Tree). Each leaf node of a L-S Tree points to its corresponding block content. A knowledge Acquisition Tool (KAT) is devised to create a Document Sample Tree from L-S Tree, in which each of its leaves contains a node content conceptually describing its corresponding block content. Then, applying …

Integrating Hypertext With Information Systems Through Dynamic Mapping, Jiangling Wan

Dissertations

This dissertation presents a general hypertext model (GHMI) supporting integration of hypertext and information systems through dynamic mapping. Information systems integrated based on this model benefit from hypertext function-alities (such as linking, backtracking, history, guided tours, annotations, etc.) while preserving their own computation capabilities. Although systems supporting integration of hypertext and interface-oriented information systems do exist in hypertext literature, there is no existing model or system effectively supporting integration of hypertext and computation-oriented information systems. GHMI makes its major contributions by both extending and specifying the well-known Dexter Hypertext Reference Model. GHMI extends the Dexter model to overcome its limitations. …

Theory And Design Of Portable Parallel Programs For Heterogeneous Computing Systems And Networks, Ying-Chieh Wu

Dissertations

A recurring problem with high-performance computing is that advanced architectures generally achieve only a small fraction of their peak performance on many portions of real applications sets. The Amdahl's law corollary of this is that such architectures often spend most of their time on tasks (codes/algorithms and the data sets upon which they operate) for which they are unsuited. Heterogeneous Computing (HC) is needed in the mid 90's and beyond due to ever increasing super-speed requirements and the number of projects with these requirements. HC is defined as a special form of parallel and distributed computing that performs computations using …

Development Of A Multivariate Qsar Model To Predict Desorption Of Halogenated Aliphatic Hydrocarbons From Activated Sludge Solids, Sudhi Ranjan Mukherjee

Dissertations

Data collected from different wastewater treatment processes have provided statistically significant evidence that many toxic organic contaminants on EPA's list of priority pollutants concentrate several orders of magnitude greater than influent concentrations in industrial and municipal wastewater sludges. Because of the reversibility of sorption processes, it is possible for sorbed organic compounds to desorb at a later time, hence making disposal of these sludges a potential problem. Although a number of models have been developed to predict sorption parameters, they have all been based on empirically derived descriptors whose validity is seriously compromised by the variation in available data for …

Continuous Monitoring Of Volatile Organic Compounds Using Microtrap Based Gas Chromatographic Systems, Yonghua Xu

Dissertations

Continuous analysis allows a representative portion of a sample to flow continuously through an analytical instrument, which gives analytical information with little or no delay in time. A microtrap is a small diameter tube packed with adsorbents in series. When a gaseous sample containing volatile organic compounds (VOCs) flows through the microtrap, the VOCs can be trapped selectively by adsorbents. Then a pulse of electrical current is applied to the microtrap. This rapid heating results in a desorption that can act as a sharp injection for GC separation. Thus the microtrapped sample is the total amount of VOC present in …

A Full Wave Method For Rough Surface Scattering Using Fictitious Current Distributions, Anthony A. Triolo

Dissertations

Rough surface scattering is a current topic of interest in many diverse fields. But, despite its importance, the two most widely used solution methods, the Kirchhoff and first order perturbation methods, are valid only for a restricted range of surface types. There is a large range of surface statistics for which neither of these theories is valid. There are purely numerical solutions to the problem, i.e., the integral equation technique and FDTD method, but these methods require a prohibitively large amount of computer time and storage space for use in practical applications. A full wave method has been introduced by …

Reduction Of Inertia-Induced Forces In A General Spatial Mechanism, Sahidur Rahman

Dissertations

A computer-aided design procedure has been developed for minimizing the adverse effects of the inertia-induced forces by optimum mass redistribution amongst the links of high speed general spatial linkages. The evaluation of an optimality criterion for the mass redistribution of the mechanism will be carried out with the aid of a quadratic programming technique. This has been found to be successful in minimizing inertia induced forces and torques. The validity of the optimization procedure will be demonstrated by application to one kind of spatial linkage.

No literature has been found on the balancing of a general spatial mechanism, since its …

Discrete Element Modeling Of Dry Granular Material Using A Massively Parallel Supercomputer, David W. Washington

Dissertations

It is the state-of -the-art within Geotechnical Engineering to model soils as systems of particles rather than using the traditional continuum approach. Simulating these systems of particles for geotechnical boundary value problems results in systems which are of necessity large, motivating the application of massively parallel supercomputers. This thesis pursues such an approach.

The following work describes numerical experiments using a Discrete Element Method (DEM) paradigm for soils (Trubal) together with massively parallel computers with Single Instruction Multiple Data (SIMD) architecture. The discrete element method describes the behavior of granular assemblies using the classical mechanics of discrete bodies. The computational …

The Effect Of Written Information And Reassurance On Patient Satisfaction, Anxiety, And Intent To Return For Emergency Care, June Andrea Dnsc

Dissertations

Patients' satisfaction is one of the primary goals of emergency department (ED) providers today. As emergency departments are overcrowded, stressful environments, anxious patients want to be kept informed. Nurses have the opportunity to meet these needs and possibly influence the patients' perception of the experience and intent to return for future care. This study examined the effects of providing written information and reassurance on patient satisfaction, anxiety, and intent to return for emergency care. The design was a posttest design involving a comparison between the control and three experimental groups. Two hundred and forty patients participated in the study, approximately …

Ethical Decision-Making Among Critical Care Unit Nurses, Mary Ellen Bowen Dnsc, Mn, Rn, Cnaa

Dissertations

The health care business has created complex relationships between consumers and health care institutions. Rising health costs, rationing of health care and medical technology have put critical care unit (CCU) nurses in complex environments where they must face ethical conflict. CCU nurses find themselves ill equipped to make sound decisions concerning ethical dilemmas. Nurses must ensure the patient's choices are respected and honored due to the duties inherent in the nurse-patient relationship. The purpose of this study was to explore the process of ethical decision making (EDM) as it is experienced by CCU nurses. Gaining an understanding of this process …

Nursing Faculty Connecting With Students: A Heideggerian Hermenteutical Study, Debra I. Craig Dnsc, Msn, Rn

Dissertations

This study sought to gain an insight into the phenomenon of nursing faculty members connecting with students. Caring has been espoused as a key component of nursing education for many decades. In the last 10 years the terms caring and connecting are commonly found associated with each other, and yet there is no clear definition of connecting. It is important to understand a phenomenon from the point of view of those who are experiencing it. Therefore, a study which asked nursing educators to tell stories of the times they had connected with students was undertaken. Ten nurse educators in the …

The Journey From Nonexerciser To Exerciser: A Grounded Theory Study, Keri Kuniyoshi Medina Dnsc, Ms, Rn

Dissertations

The physiological and psychological health benefits of regular physical exercise are well-documented; however, drop-out rates from both supervised and unsupervised exercise remain high. Many potential influences on exercise behavior have been studied, but with largely inconsistent results, making it difficult to identify key targets for intervention. The purpose of this study was to explore the process through which nonexercisers become exercisers, and the contextual factors which affect movement through this process, in order to enable nurses to more successfully assist clients to incorporate exercise into their lifestyles. The exercise experiences of 22 individuals who had successfully made the transition from …

The Relationship Between Principals' Length Of Administrative Experience And Organizational Leadership Behavior In Elementary Schools In Saudi Arabia, Hamad Adbulaziz Alkherb

Dissertations

The study examined educational leadership behaviors among elementary school principals in Qasim region of Saudi Arabia. Seven independent variables using a survey questionnaire among a randomly selected sample from the identified population. Self-reporting elicited, first, critical background information and, second, data concerning 60 specific leadership behavior items important to work issues, critical areas of educational administration, professional relationship situations, and leadership problems ordinarily confronted. Items were grouped according to five categories of twelve items each.

Ninety-six principals or 80% of the survey sample of 120 responded. Focus of the study derived importantly from an extensive and complex review of literature …

A Comparison Of Youth Living Environment In Small And Large Communities Of Michigan, Huilan Yang

Dissertations

This study compares youth living environment in small and large communities in Michigan. The comparison includes three areas of youth living environment: community environment, financial environment, and educational environment. Community in this study is defined as school district. Data are extracted from an existing database developed by the National Center for Educational Statistics titled School District Data Book (SDDB). Out of 560 Michigan school districts included in SDDB, 370 are used in the data analysis, excluding the Detroit City School District and 189 medium-sized districts. Fifteen variables are selected for comparison, categorized under the three areas of youth environment. The …

Integrating Knowledge And Action: A Study Of Leadership In The Development Of Master's Degree Programs In Liberal Studies, Janet L. Littrell Edd

Dissertations

Master's degree programs in liberal studies (MALS programs) have proliferated in the United States over the past twenty years. Studying the leadership relationships that faculty and administration form during the MALS program development process provides insight into how non-traditional graduate programs may be developed in the future. The purposes of the study were to investigate the development of MALS programs, and to examine the leaders and followers who successfully advanced the MALS program development agenda. The specific objectives of the study were (1) to examine the theoretical bases and curricular frameworks of MALS programs; (2) to explore how individuals and …

Lobbying In The Nonprofit Sector: A Study Of Practice And Values, Larry A. Buzas

Dissertations

Executive directors of nonprofit organizations were interviewed to determine their lobbying practices. Direct lobbying and grassroots lobbying, as defined by P. A. 94-455 were studied. Independent variables include: (a) formal organizational support, (b) organizational affiliation, (c) organizational characteristics, and (d) the executive directors' perceptions and demographic characteristics.

Data were collected during semi-standardized interviews. A random sample of 50 executive directors of nonprofit organizations in Michigan was selected. The research shows that executive directors of nonprofit organizations do lobby policy makers at the local, state, and federal levels using the following techniques: (a) face-to-face visits, individually or with coalitions, including providing …

The Public Administrationist As Civic Shaman: The Self-Reflective Integrator Of Policy Frames Of Reference And Social Character, Phillip A. Brown

Dissertations

This study discusses the discipline of Public Administration and the Public Administrationist in relation to policy frames of reference and social character. The relationship of policy frames of reference and social character is the basis for public trust As the American political system becomes more and more fragmented, public administrationists, sometimes by default, become the trustees for safeguarding the public trust.

The concept of policy frames of reference, as it evolves in this discussion, refers to the ability of the public administrationist to understand the interactions of changing issues impacting on the interactions of changing issues, or quantum thinking. Social …

Crises In The Regulation Of Long-Term Care, Randall Earl Phillips

Dissertations

This study reviews the history of the legislative process that led to the passage of the Nursing Home Reform Act of 1987 and the implementation of the regulations. The analysis uses the model of Masmanian and Sabatier to identify the variables and assess their impact on the implementation process. The content of the regulations in terms of various statutory and nonstatutory variables is assessed, and an estimate is made of their effect on the program.

Three aspects of the regulations are examined. First, the relative importance of how compliance is to be determined--subjectively, objectively, or clinically. Second, the design and …

An Evaluation Of Privatization, Taxes, And User Fees As Alternative Strategies For Municipal Trash Collection, James Neubecker

Dissertations

This study consists of evaluating the perceived quality of the various methods of collecting residential trash and paying for that collection in four Michigan cities. The cities selected are East Lansing, Lincoln Park, Saginaw, and Wyoming. Theyshare similar demographic characteristics, including median income and population size, as well as number and location of trash pick-ups. The study compares paying for trash collection services with tax dollars, user fees, and direct private charges to the vendor. It also evaluates the residents’ perceptions of quality when municipal workers are compared with private company workers providing trash collection services.

Questionnaires were sent to …

Adolescent Students At Risk: The Roles Of Stress, Distress, And Coping, Jennifer Massicotte

Dissertations

Male and female adolescents who reported recent suspension/ threats of suspension or academic failure were compared to male and female adolescents who did not report these two variables of dropping out on three measures--the discrete negative uncontrollable events experienced (LEQ-A, Garmezy, Masten, & Tellegen [1985]), the level of distress (GHQ-30, Goldberg [1972]), and the types of coping skills used (A-COPE, Patterson & McCubbin [1983]). Native and non-Native at risk for suspension and academic failure rates were also compared using archival data from a community mental health survey of 714 adolescents (36 Native) attending high school in Northern Ontario.

Native adolescents …

The Experiences Of Mid-Career Elementary Teachers, Susan H.L. Johnston Edd

Dissertations

The demographics of the teaching population in British Columbia indicate a significant number of teachers in mid career. Their cares, concerns, and interests dramatically influence educational activity in the province. The experiences of these educators lie within a context of major restructuring of the entire provincial school system and substantive educational change mandated by the government of British Columbia. Using a phenomenological approach, this study explores the experiences of seven, mid-career, elementary school teachers in one British Columbia school district; investigates how these teachers experience system-wide, mandated, educational change; and suggests implications of these understandings for leadership practice. During three, …

Real Time Control Of Nonlinear Dynamic Systems Using Neuro-Fuzzy Controllers, Amitava Jana

Dissertations

The problem of real time control of a nonlinear dynamic system using intelligent control techniques is considered. The current trend is to incorporate neural networks and fuzzy logic into adaptive control strategies. The focus of this work is to investigate the current neuro-fuzzy approaches from literature and adapt them for a specific application. In order to achieve this objective, an experimental nonlinear dynamic system is considered. The motivation for this comes from the desire to solve practical problems and to create a test-bed which can be used to test various control strategies. The nonlinear dynamic system considered here is an …

Investigation Of Dynamic Friction In Lubricated Surfaces, Hanuman Rachoor

Dissertations

The research reported in this dissertation is concerned with the development of friction models for lubricated contacts. A few analytical models have been developed to investigate the friction under dynamic velocity conditions. In this study, two different tribological situations such as conformal and non-conformal contacts have been chosen. Friction modeling covers boundary, mixed and full fluid film friction regions. A new theory based on the elastic properties of the surface materials, and fluid film properties of the lubricant at the contact has been developed to determine the dynamic friction in boundary, mixed and full hydrodynamic lubrication regions. In the full …