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The Effects Of Writing Assignments On Second-Semester Calculus Students' Understanding Of The Limit Concept, Melanie A. Wahlberg

Dissertations

The purpose of this study was to determine the impact of writing assignments on second-semester calculus students’ understanding of the limit concept, using both qualitative and quantitative techniques. The study involved two sections of second semester calculus (n = 37, 34) at Western Michigan University during the fall semester of 1997.

The treatment group completed six writing tasks focusing on the mathematical concept of limit. These conceptually-oriented writing assignments replaced some of the problem sets that the instructor would have normally assigned. The control group did not engage in writing tasks but handed in problem sets more frequently than the …

Disruption Of The Discriminative Stimulus Effects Of (+)-3, 4-Methylenedioxymethamphetamine (Mdma) By (± )-Mdma Neurotoxicity: Protection By Fluoxetine, Thomas B. Virden Iii

Dissertations

It is well established that repeated, high doses of 3, 4-methylenedioxymethamphetamine (MDMA) result in the long-term depletion of serotonin levels and destruction of serotonergic terminals in various locations in the brains of a variety of species. Further, it is also well known that concomitant injections of the serotonin reuptake inhibitor, fluoxetine, prevents this deterioration. It has recently been noted that such MDMA neurotoxicity disrupts stimulus control in rats trained to discriminate MDMA from saline in a drug discrimination procedure (Schechter, 1991a).

In order to extend Schechter's findings to the optical isomers of MDMA and to explore the potential of fluoxetine …

The Comparison Of Selection-Based And Topography-Based Verbal Behavior Across Populations, Carl T. Sundberg

Dissertations

Michael (1985) distinguished between selection-based (SB) and topography-based (TB) verbal behavior. Several studies comparing the ease of learning the two systems have shown conflicting results. The data indicate that subjects with fewer lower verbal skills have done better with TB systems (subjects with developmental disabilities in studies by Hodges & Schwethelm, 1984; Sundberg & Sundberg, 1990; Weirmanski, 1984; Wraikat, 1991; Wraikat, Sundberg, & Michael, 1991; and the bottom half of subjects in Cresson, 1994). The higher functioning subjects have done better (or have not shown a difference) with SB systems. (Bristow & Fristoe, 1984; Stratton , 1992; Tan, Bredin, Poison, …

Fostering Reflective Thinking In First-Semester Calculus Students, Pamela Crawford

Dissertations

This study focuses on the fostering of reflective thinking in students in a reform calculus course through completion of homework assignments incorporating reflective tasks, and the effect of these assignments on student understandings of calculus and conceptions of mathematics. The study, conducted in Fall 1997, involved two sections of first-semester calculus at a large midwestern university and used quantitative (n = 25, 18) and qualitative (n = 7) techniques.

Homework assignments incorporating reflective tasks included asking students to compare and contrast textbook ideas; to write about how obstacles were overcome as they attempted exercises; to develop concept maps organizing and …

Relationships Between Posttraumatic Stress, Acculturation, And Maternal Sensitivity In Vietnamese And Hmong Mothers, Gwendolyn F. Foss Dnsc

Dissertations

The purposes of this study were to determine if posttraumatic stress (PTS), depression, and anxiety occurred in a community sample of Vietnamese and Hmong mothers and to describe relationships between PTS, depression, anxiety, acculturation and maternal sensitivity. Transition theory (Bridges, 1980), and a conceptual model of parenting in immigrant populations building on Belsky's (1984) work, provided the theoretical framework (Foss, 1996). The sample was divided evenly between Vietnamese and Hmong participants. Ages ranged from 17–43 years, time lived in the United States ranged from 3–21 years, and education ranged from no formal education to completion of college. Maternal sensitivity was …

Units In Integral Group Rings For Direct Products, Richard M. Low

Dissertations

Given a finite group G and the ring of integers, one can form the integral group ring ZG . A natural problem to investigate is to find a description of the group of units for this ring ZG. Since the unit problem for integral group rings arises in the contexts of algebraic topology, number theory, and algebra, it is an important question to try to answer. For this reason, it has drawn the attention of researchers from diverse areas of mathematics.

Graham Higman (circa 1940) made substantial contributions to the solution of this problem, in the case where G was …

Analytical And Experimental Study Of Investment Casting With Laser Stereolithography Models, Wen-Long Yao

Dissertations

This dissertation presents an analytical and experimental investigation of ceramic shell cracking during the burnout process in investment casting with internally webbed laser stereolithography (SLA) patterns. Included in the consideration are the cracking temperature of the ceramic shell, the web link buckling temperature, and the glass transition temperature of the epoxy resin. The hypothesis is that shell cracking will occur when the cracking temperature is lower than the glass transition temperature and the web buckling temperature.

An analytical and experimental study has been conducted, with the cross-sectional area, the span length of the web structure, and the shell thickness being …

A Combined Simulated Annealing And Tabu Search Strategy To Solve Network Design Problem With Two Classes Of Users, Qifeng Zeng

Dissertations

A methodology to solve a transportation network design problem (TCNDP) with two classes of users (passenger cars and trucks) is developed. Given an existing highway system, with a capital investment budget constraint, the methodology selects the best links to be expanded by an extra lane by considering one of three types of traffic operations: exclusive for passenger cars, exclusive for trucks, and for both passenger cars and trucks such that the network total user equilibrium (UE) travel time is minimized.

The problem is formulated as an NP-hard combinatorial nonlinear integer programming problem. The classical branch and bound methodology for the …

Automobile Air Bag Inflation System Using Pressurized Carbon Dioxide, Bart Adams

Dissertations

A novel air bag inflator based on the evaporation ofliquefied carbon dioxide was developed. A detailed qualitative model wasestablished on the basis of an extensive experimental study. An integratedquantitative model of this inflator was constructed.

The system was studied by discharging the inflatorinto a tank and measuring pressure and temperature evolution (0-50 ms). Thedispersion of the two-phase spray duringinflation was investigated by high-speed cinematography.

The optimal storage pressure of the liquid CO₂was found to be 2000 psig (at 22 °C). Two distinct inflator behaviors wereidentified. First, at conditions corresponding to an initial entropy below the critical point, atwo-phase …

Space-Time Reduced Rank Methods And Cfar Signal Detection Algorithms With Applications To Hprf Radar, Tareq F. Ayoub

Dissertations

In radar applications, the statistical properties (covariance matrix) of the interference are typically unknown a priori and are estimated from a dataset with limited sample support. Often, the limited sample support leads to numerically ill-conditioned radar detectors. Under such circumstances, classical interference cancellation methods such as sample matrix inversion (SMI) do not perform satisfactorily. In these cases, innovative reduced-rank space-time adaptive processing (STAP) techniques outperform full-rank techniques. The high pulse repetition frequency (HPRF) radar problem is analyzed and it is shown that it is in the class of adaptive radar with limited sample support. Reduced-rank methods are studied for the …

A Low-Cost High-Speed Twin-Prefetching Dsp-Based Shared-Memory System For Real-Time Image Processing Applications, Charalambos Stephanou Christou

Dissertations

This dissertation introduces, investigates, and evaluates a low-cost high-speed twin-prefetching DSP-based bus-interconnected shared-memory system for real-time image processing applications. The proposed architecture can effectively support 32 DSPs in contrast to a maximum of 4 DSPs supported by existing DSP-based bus- interconnected systems. This significant enhancement is achieved by introducing two small programmable fast memories (Twins) between the processor and the shared bus interconnect. While one memory is transferring data from/to the shared memory, the other is supplying the core processor with data. The elimination of the traditional direct linkage of the shared bus and processor data bus makes feasible the …

Removal Of Volatile Organic Compound (Voc) Vapors In Biotrickling Filters : Process Modeling And Validation With Chlorinated Aromatic Compounds, Christos J. Mpanias

Dissertations

This study dealt with the removal of vapors of volatile organic compounds from airstreams in biotrickling filters (BTFs). A detailed general model was developed for describing the process under steady-state conditions. The model accounts for mass transfer between phases (air, liquid, biofilm) and biodegradation of pollutants in the biofilm. It also accounts for potential kinetic interactions among pollutants as well as potential process limitations by oxygen availability.

The general model was experimentally validated using mono-chlorobenzene (m-CB) and ortho-dichlorobenzene (o-DCB) as model compounds either alone or in mixture with each other. Before BTF experiments were undertaken, a systematic kinetic study was …

Robust Fuzzyclustering For Object Recognition And Classification Of Relational Data, Sumit Sen

Dissertations

Prototype based fuzzy clustering algorithms have unique ability to partition the data while detecting multiple clusters simultaneously. However since real data is often contaminated with noise, the clustering methods need to be made robust to be useful in practice. This dissertation focuses on robust detection of multiple clusters from noisy range images for object recognition. Dave's noise clustering (NC) method has been shown to make prototype-based fuzzy clustering techniques robust. In this work, NC is generalized and the new NC membership is shown to be a product of fuzzy c-means (FCM) membership and robust M-estimator weight (or possibilistic membership). Thus …

The Intelligent Browser For Texpros, Chih-Ying Wang

Dissertations

Browsing is a technique, which helps users to formulate their query and retrieve information in the information retrieval system. This technique provides users with capabilities of understanding their information needs and gaining system knowledge during the course of the browsing and thus it eases the users' burden when issuing queries. The basic components of the browser provides an underlying structure which allows users to navigate and a browsing process controller which provides users with the needed assistance during each browsing session.

In this dissertation, a new infrastructure (OP-Net), transformed from the existing object network is proposed. Each object in the …

Performance Improvements In Wireless Cdma Communications Utilizing Adaptive Antenna Arrays, Weichen Ye

Dissertations

This dissertation studies applications of adaptive antenna arrays and space-time adaptive processing (STAP) in wireless code-division multiple-access (CDMA) communications. The work addresses three aspects of the CDMA communications problems: (I) near-far resistance, (2) reverse link, (3) forward link. In each case, adaptive arrays are applied and their performance is investigated.

The near-far effect is a well known problem which affects the reverse link of CDMA communication systems. The near-far resistance of STAP is analyzed for two processing methods: maximal ratio combining and optimum combining. It. is shown that while maximal ratio combining is not near-far resistant, optimum combining is near-far …

Modelling Of In-Situ Bioremediation With Emphasis On Inhibitory Kinetics And Biomass Growth, Dilip Kumar Mandal

Dissertations

This thesis was motivated by the need for better engineering tools to predict the extent of contaminant plume migration in the saturated zone. The principal result was a mathematical model analogous to a catalytic packed-bed reactor, in which the subsurface was considered to be composed (conceptually) of soil aggregates (the "catalyst" particles, in which biodegradation, diffusion, and sorption take place), and a mobile phase (groundwater) passing around the aggregates, in which convection, axial diffusion, and mass transfer from the aggregates take place.

The modelling emphasis was on a more detailed exposition of the biokinetics of the system (including an inhibitory …

Knowledge-Based Document Filing For Texpros, Xien Fan

Dissertations

This dissertation presents a knowledge-based document filing system for TEXPROS. The requirements of a. personal document processing system are investigated. In order for the system to be used in various application domains, a flexible, dynamic modeling approach is employed by getting the user involved in document modeling. The office documents are described using a dual-model which consists of a document type hierarchy and a folder organization. The document type hierarchy is used to capture the layout, logical and conceptual structures of documents. The folder organization, which is defined by the user, emulates the real world structure for organizing and storing …

Toward Sustainable River Basin Management In China: The Challenge Of Institutional Reform And Capacity Building, Ke Chen

Dissertations

Throughout human history water has been a key determinant for national development and human welfare. Existing river basin management (RBM) institutions and practices in China are incapable of fully meeting current needs. much less the challenges of sustainable development. Conceptual and institutional reforms will be needed to meet these challenges. New interdisciplinary thinking about the complex interactions between ecological. socio-economic and technological systems is reviewed to provide an ecosystemic perspective on RBM problems. An analytical framework which is interdisciplinary. systemic. historical. and comparative is then employed to focus on the institutional aspects of RBM regimes and their etlects on natural-human …

Major Trauma Outcomes: At What Cost? And For Whom? A Cost-Effectiveness Analysis, A. Elaine Bond Dnsc, Msn, Aprn, Ccrn

Dissertations

The purpose of this triangulated descriptive study was threefold: (a) to identify the financial costs for acute trauma care, including costs for those who die early in treatment, and who pays those costs; (b) to identify the relationship between costs and severity of injury; and (c) to identify survivor functional and psychosocial costs, or quality of life, not only by current health care outcome criteria, but also from patients' and families' perspectives. Retrospective review determined the financial differences (total charges of $9,945,973 and institutional costs of $7,089,962) for 370 patients' severity of injury and functional outcomes at discharge, using the …

Testing A Theoretical Model Of Critical Thinking And Cognitive Development, Jane Rapps Dnsc, Ms, Msed, Rn

Dissertations

The goal of nursing education is to educate individuals in such a way that they become self-determining, independent thinkers who are prepared to keep pace with the rapidly changing demands of today's health care system. Nurses must utilize critical thought and reasoned action in clinical practice in order to render state of the art health care for individuals, families, groups, and communities. The purpose of this study was to test a proposed theoretical model of critical thinking and cognitive development. Perry's theory of adult cognitive development and Kataoka-Yahiro and Saylor's Critical Thinking Model for Nursing Judgment guided this research. Data …

Being Alone: The Experience Of Elderly Homebound Females, Sharon Davis Burt Dnsc, Msn, Rn

Dissertations

Elderly women comprise one of the fastest growing segments of the population in the United States. This growth is due in large part to increasing longevity, and a woman's life expectancy has now reached 79 years. However, along with those added years comes an increase in morbidity and a greater likelihood of living alone. This study describes the life experience of a specific group of elderly women, those who are homebound and living alone. When elderly women are included in research, the same combination of descriptors used for the participants in this study has not been incorporated. Consequently, while much …

The Journey Through Perspective Transformation: Learning Nursing Theory, Judith R. Heggie Dnsc, Ms, Rn

Dissertations

Through the use of grounded theory, educational methods most useful for nurses to achieve a perspective transformation, as exemplified by learning nursing theory were examined. Perspective transformation is a theory originally developed by Mezirow (1978) in a study of older women returning to college for additional education. Mezirow defined perspective transformation as the alteration or change of meaning perspectives. Perspective transformation in an individual can be compared to a paradigm change within a scientific community. Within the nursing literature on perspective transformation, most articles related to the perspective transformation needed for nurses to learn to use nursing theory as the …

The Experience Of Decision-Making Among Telephone Advice/Triage Nurses, Ann Mayo Dnsc, Msn, Rn

Dissertations

The role of the telephone advice/triage nurse is both complex and demanding. All decisions are made while assessing patients without seeing or touching patients. In addition, the role is often developed to decrease health care costs which can be perceived by nurses as being in conflict with their nursing beliefs. The ambiguous nature of the role makes these nurses' daily experiences with decision-making a challenge. Using a phenomenological method, the lived experience of decision-making among telephone advice/triage nurses was explored by conducting multiple interviews with ten nurses. The internal structure of the lived experience was identified through the philosophical perspective …

Reflections Of Reflections Of Reflections: A Multi-Case Study Of Women Educators' Callings To The High Arctic, Judith Knapp Edd

Dissertations

This study examines the stories of six women educators who were called to teach in remote Aboriginal communities in the Northwest Territories, Canada, from 1970 to 1985. Placed within a historical context, I set out to understand what called each educator to teach in a cultural context so different from her own in Canada's Arctic. In order to arrive at a deeper, more intrinsic understanding of her career decisions, I explored each educators calling through three, increasingly deeper levels of reflection. In Reflections, as “in an instance of reflecting,” I explored each participant's call to teach, specifically her calling to …

Molecular Modelling Studies Of Acetylcholinesterase, Charilaos E. Linaras

Dissertations

The controversial role of electrostatic interactions in the process of steering of acetylcholine into the active site of acetylcholinesterases was investigated in this study. A novel methodology was implemented to simulate the process of recognition of acetylcholine by Torpedo Californica and both wild type and charge neutralized mutated Human AChE. The obtained results suggest the important role of coulombic interactions in the steering process. The steering process of selected irreversible AChE inhibitors was also simulated supporting the role of electrostatic interactions in the recognition process.

A novel methodology was also employed to model the covalent adducts of Torpedo Californica and …

The Relationship Of Saudi Managers’ Characteristics And Their Support Of The Transfer Of Training To The Workplace, Khalid M. Alhazmi

Dissertations

Many HRD professionals have pointed out that one of the most important elements for transfer of training to the workplace is management support. However, there is little discussion concerning management characteristics that support the transfer of training to the workplace. The purpose of this study was to investigate management characteristics that inhibit or promote the transfer of training to the workplace and to provide information regarding those characteristics to companies.

This study focused on one main question: Do management characteristics have an effect on management support of the transfer of training to the workplace? To answer this question, a study …

The Role Of The Parish Pastor As Mental Health Provider: Counseling Competency And Personality Characteristics, John Phillip Burgess

Dissertations

United Methodist pastors, serving churches in the State of Michigan, were surveyed regarding their participation in counseling and referral to other mental health providers. In addition to a demographic questionnaire, each pastor completed two standardized instruments, the Counseling Self-Estimate Inventory (COSE) (Larson, et al., 1992) and the Edwards Personal Preference Schedule (EPPS) (Edwards, 1959). Dependent variables of amounts and types of counseling being conducted, scores from the COSE and EPPS, and four satisfaction ratings, were compared across several independent variables including: pastor's gender, age, race, length of service, theological orientation, and amount of academic preparation specifically related to mental health/counseling …

The Effect Of Rate Vs. Number Of Emissions Of An Operant Behavior On Behavior Probability, Michael D. Makepeace

Dissertations

The present study compared three conditions in the training of a set of operant responses on later probability of behavior that represented a generalization or co-adduction of the behavior emitted in training. In two of the conditions, the numbers of emissions of target responses were exactly equal; in a third condition, the number of emissions of target responses was a lesser quantity. The two conditions with an equal number of emissions of target responses were distinguished by the rate of responses yielded by contingencies surrounding training in each condition. In one of these conditions, subjects responded at a relatively low …

A Paleoclimatic Study Of The Midwestern United States From The Stable Isotope Records In Lake Sediments, Norman Alan Lovan

Dissertations

No abstract provided.

The Role Of Ethnicity Among International Students In Adjustment To Acculturative Stress, Mohd. Tajudin Hj Ninggal

Dissertations

This study examined whether there were differences in six acculturative stress themes among three Malaysian ethnic groups who were enrolled at Western Michigan University during the Fall, 1997 semester. The study also investigated whether the following demographic attributes: (a) gender, (b) academic major, (c) financial sponsorship, (d) family socioeconomic status, (e) type of residential setting, and (f) scores on the Test of English as a Foreign Language (TOEFL) affected Malaysian students in relation to the six acculturative stress themes: (1) Perceived Discrimination, (2) Homesickness, (3) Perceived Hate, (4) Fear, (5) Culture Shock, and (6) Guilt.

A total of 138 respondents …