Physical Sciences and Mathematics Commons^™

Hydrogeology And Stable Isotope Investigations Of A Landfill Impacted Site In Southwest Michigan, Eliot Anong Atekwana

Dissertations

The Cork Street landfill in the City of Kalamazoo is unlined and constructed in glacial drift material. Although water quality in some of the landfill monitoring wells is poor, the degree of the landfill’s influence to groundwater, wetlands and Davis Creek located downgradient of the landfill is unknown. The objective of this study is to evaluate the degree of the landfill’s impact in this region through hydrologic and stable isotope analysis.

Site characterization using geophysical surveys and specific conductance measurements indicates highly conductive shallow groundwater probably attributable to groundwater contamination. Hydrologic evaluation of this region shows that groundwater flows towards …

Statistical Graphics: Applications To The R And Gr Methods In Linear Models, Mei Huang Wang

Dissertations

Statistical graphics combine statistics and graphics together to visually display analytical statistical results. They present information in a way that is very easy to understand and, furthermore, they frequently reveal information that is hidden from numerical summaries. Our purpose of this study is to explore the field of statistical graphics by investigating their application to statistical methods in the context of the R and GR methods in linear models. We consider the problems of score selection, R-diagnostics, and comparison of the R- and GR-fits.

We have developed a user friendly program which uses dynamic graphics and a user interface to …

Integrity Of Digraphs, Robert Charles Vandell

Dissertations

The vertex-integrity of a digraph D, denoted I(D), is defined to be the minimum over aIII subsets X of the vertex set of D for the quantity IXI + m(D - X), w here IXI is the number of vertices in X and m(D - X) is the maximum order of a strong component in the digraph D - X. In a like manner, the arc-integrity of the digraph D, denoted I’(D), is defined to be the minimum over all subsets Y of the arc set of D for the quantity IYI + m(D - Y), where IYI is the …

Gender Discourse In Small Learning Groups Of College-Level Developmental Mathematics Students, Allen W. Emerson

Dissertations

This study was motivated by the question as to whether women’s and men’s membership in different gender communicative cultures gives rise to gender differentiated ways of talking that are implicated in the failure of a mixed-sex group to achieve good mathematical discourse when women and men sit face to face engaged in various mathematical tasks. If so, in what ways and to what effect is gender discourse implicated in the failure of a mixed-sex group to achieve good mathematical discourse?

Models of feminine and masculine discourse styles based on the theory of communicative cultural difference, as well as a model …

Reductive Dehalogenation Of Chlorinated Aromatic And Aliphatic Hydrocarbons Under Anaerobic Conditions, Monica Turner Togna

Dissertations

The process of reductive dehalogenation involves the removal of a halogen substituent from a molecule with the concurrent addition of electrons to the molecule, resulting in a more reduced and often less toxic product. Anaerobic bacteria have the potential to utilize hazardous chlorinated aromatic and aliphatic hydrocarbons as electron acceptors in metabolic reductive dehalogenation processes.

In experiments performed with chlorinated aromatic compounds a highly enriched anaerobic culture stoichiometrically converted 2,4,6-trichlorophenol (2,4,6-TCP) to 4-monochlorophenol. Dehalogenation occurred only in alkaline media (pH 8-9) at concentrations of 2,4,6-TCP up to 1 mM. Data indicated that the dehalogenating organism did not fit into any …

Scaling Up Of Water-Based Organic Reactions, Chen Gu

Dissertations

Three water-based organic reactions, Diels-Alder, epoxidation of olefins, and free-radical bromination have been investigated as an approach to pollution prevention. The first two systems were scaled-up by at least a factor of 20. These reactions are of special interest to the pharmaceutical and speciality chemical industries. The photo-induced free-radical bromination of alkanes with bromine in water was studied in a two-phase system. Experimental results show that all reactions have advantages resulting from being conducted in water, such as reaction rate acceleration, reaction selectivity increase, and the absorption of water-soluble gas byproduct by solvent water.

The effects of stirring rates, temperature, …

Effect Of Vitamin Supplementation On Biodegradation Of Aliphatic Hydrocarbons And Diesel Fuel, Susmita Guptapal

Dissertations

Bioremediation of hazardous wastes is proven to be environmentally benign and most cost effective technology when proper conditions are provided. However, commercialization of this method still requires comprehensive research to enhance the degradation rate to make the technology more acceptable for implementation. In this research a unique approach to increase the rate of biodegradation by vitamins supplementation was studied.

Five vitamins, niacin, biotin, folic acid, thiamin and pantothenic acid were selected for the present study. Different short chain (C₈ and C₉), and long chain (C₁₆ and C₁₇) aliphatic hydrocarbons and diesel fuel (a mixture …

A Graph Theoretic Study Of The Similarity Of Discrete Structures, Heather D. Gavlas

Dissertations

A basic problem in drug design consists of finding a compound that satisfies a spectrum of biological and chemical properties. Although drug design problems are central to pharmaceutical research, statisticians have yet to become involved in this area as these problems are viewed statistically as optimization problems. Before statistical optimization procedures can be defined on these spaces whose points are structures and not vectors, very basic mathematical notions of distance must be defined. Graphs have been used as mathematical models to represent the bonding arrangements of molecules for quite some time. In fact, if some of the methodology used by …

Random Cayley Maps, Michelle Schultz

Dissertations

Determining the orientable surfaces on which a given graph can be imbedded is the central problem of topological graph theory. The natural setting for studying this problem is random topological graph theory, where a probability model is defined on the space of all labeled 2-cell imbeddings of a connected graph. The major focus of this dissertation is the study of Cayley maps in the setting of random topological graph theory.

A Cayley graph provides a representation of a finite group and a fixed generating set for the group. A Cayley map is an imbedding of a Cayley graph whose vertex …

Ionization And Charge Changing In 0.5 - 8 Qmev Li^Q+ + He (Q=1,2,3) Collisions And Setup Of An Electron Spectrometer Control System, Oliver Woitke

Dissertations

Projectile charge changing and target ionization cross sections are measured for 0.5 to 8 qMeV Li^q+ + He (q=1,2,3) collisions. Total cross sections for single-electron capture (for L i^1,2,3+) and single-electron loss (for L i^1,2+) are obtained and compared to existing experimental and theoretical data. Also, single and double target ionization of He associated with specific outgoing projectile charge states are identified using coincidence techniques. Cross sections for target ionization associated with no projectile charge change (direct ionization), single-electron capture, and single-electron loss are measured and compared to existing experimental data and to available calculations. Double-to-single target ionization ratios R …

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 …

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 …

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 …

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 …

Ground Water Movement Through The Highly-Fractured Crystalline Core Of A Large-Scale, Foreland Uplift, Roy Al Gorge Arch, South-Central Colorado, Timothy L. Clarey

Dissertations

The objectives of this study were twofold: ( 1) to examine the well-exposed, basement core of the Royal Gorge arch as a large-scale, field test of ground water flow through a fractured, crystalline, aquifer system; and (2) to devise a method to more accurately determine the direction of maximum aperture of a fractured aquifer through structural and hydrogeologic analysis.

The recognition of a preferred direction of maximum aperture in a fractured aquifer remains an important hydrogeologic consideration because flow through a fracture is proportional to the cube of the aperture width. Previous studies of hydraulic directions using fracture orientation techniques …

Identifying And Exploiting Concurrency In Object-Based Real-Time Systems, Guohui Yu

Dissertations

The use of object-based mechanisms, i.e., abstract data types (ADTs), for constructing software systems can help to decrease development costs, increase understandability and increase maintainability. However, execution efficiency may be sacrificed due to the large number of procedure calls, and due to contention for shared ADTs in concurrent systems. Such inefficiencies are a concern in real-time applications that have stringent timing requirements. To address these issues, the potentially inefficient procedure calls are turned into a source of concurrency via asynchronous procedure calls (ARPCs), and contention for shared ADTS is reduced via ADT cloning. A framework for concurrency analysis in object-based …

The Development, Molecular Characterization And Application Of A Model Stratum Corneum Lipid System, Rita M. Hatfield

Dissertations

No abstract provided.

Photophysics And Photochemistry Of Carbocations, Maria R. Valentino

Dissertations

No abstract provided.

Molecular Studies Of Human Erythrocyte Spectrin: Head To-Head Interactions, Nasser Qtaishat

Dissertations

No abstract provided.

The Synthesis Of Azure B Derivatives: Potential Pro-Drugs For Photodynamic Therapy, Carla M. Edwards

Dissertations

No abstract provided.

Development Of A Unique Photothermal Interferometer, Michael Henry

Dissertations

No abstract provided.

Na+-H+ Exchange And Na+-Li+ Exchange In Human Erythrocytes: An Nmr Investigation, Yuling Chi

Dissertations

No abstract provided.