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Geochemical And Isotopic Characterization Of Shallow Basinal Brines From The Makgadikgadi Pans Complex, Northeastern Botswana: Determination Of The Sources Of Salinity, Loago N. Molwalefhe

Dissertations

Isotopes and chemical tracers have been used to constrain the sources and causes of salinity in shallow groundwater brine from the Makgadikgadi Basin, northeastern Botswana. The brine is massively rich in chloride and sodium, and moderately rich in carbonates, sulphate and potassium, and is distinctively poor in divalent cationic species. Various models that have been advanced to explain the origin of the brines include evaporative enrichment at the surface and density-induced infiltration, dissolution of evaporites, and trapped connate water.

This study presents the compositional variability and behaviors of ·the stable isotopes of carbon (S¹³C) and oxygen (S^{18 …}

How Secondary School Mathematics Teachers Construct An Understanding Of "Appropriate Use" Of Graphing Calculators In The Context Of Collegial Inquiry, Marcia L. Weller Weinhold

Dissertations

No abstract provided.

Effects Of Sodium Metaborate On Kraft Pulping, Biljana M. Bujanovic

Dissertations

The kraft lime cycle can be either replaced or supplemented by borate-based autocausticizing (total or partial autocausticizing, respectively). The borate-based autocausticizing uses sodium metaborate to produce sodium hydroxide in the two-step reaction performed in a recovery boiler and dissolving tank. In accordance with the borate-based autocausticizing chemistry, sodium metaborate is an additional chemical in both pulping and recovery. The studies of kraft pulping in the presence of sodium metaborate provide insight into the effect which sodium metaborate might have on the pulping process including the delignification rate, selectivity of lignin removal, and the properties of both pulp and black liquor. …

Psychophysically Derived Work Frequencies Associated With Roof Shingling Operations Involving Change In Grade, Sang Dae Choi

Dissertations

The objective of this study was to investigate the effect of roof slope on psychophysical roof shingling frequency. Twelve healthy males (21-30 years old) were used as participants. Experiment one was designed to determine Maximum Acceptable Roof Shingling Frequency (MARSF) for a workday period using psychophysical methodology. Results indicate that 198 shingles/hr is an acceptable roof shingling frequency for a workday. Furthermore, 2 hours is an acceptable testing period (equivalent to the workday). Postural sway and physiological variables support these findings. Experiment two was designed to study the effect of slope (18°, 26°, and 34°) on MARSF. Experiment two indicates …

Preparing Teachers To Use Technology: The Webquest In The Secondary English Language Arts Methods Classroom, Melinda C. Dobson

Dissertations

This study focuses on why and how English language arts methods instructors can integrate WebQuest development into their courses. Behavioral, cognitive, and constructive learning theory are established as a theoretical basis for introducing the WebQuest into the English language arts methods curriculum. Practicing teachers are surveyed about their WebQuest-use to identify positive and negative outcomes of the activity. National and international standards the WebQuest fulfills are identified. This study focuses on how to integrate technology in general into the methods course and then documents the development of the researcher's WebQuest and that of three different secondary English language arts methods …

Three Essays On Financial Intermediation, Capital Formation, And Economic Growth And Development, Md. Habibur Rahman

Dissertations

This dissertation contains three essays on financial intermediation, capital formation, and economic growth and development. The first essay presents a theoretical model explaining the role of financial intermediation in capital formation and economic growth. It outlines a model of search and matching equilibrium in financial economies where a lender owns capital and an entrepreneur owns entrepreneurial skill and output is produced when search generates a meeting between a lender and an entrepreneur. It is shown that investment in capital and skill is inefficient in autarky due to search frictions and an externality. We examine the autarkic equilibrium under bargaining-without-search and …

Taylor-Based Monetary Policy Rules: Are They Forward-Looking, Data Congruent, And Asset Price Responsive?, Rajeev Sooreea

Dissertations

This dissertation presents three essays to analyze a class of Taylor-based monetary policy rules that forms the basis of contemporary monetary policy decisions. The first essay examines whether policy rules are forward-looking. It proposes the methodology that, if the parameters of the Taylor rule change when the mechanism generating inflation changes, that is the Lucas critique applies, then inflation is not superexogenous for the parameters of the rule. In this case where superexogeneity fails, the rule is forward-looking. However, the results indicate that, although there is structural break in the inflation volatility process as evidenced by a model of heteroskedastic …

Irradiation Induced Order-Dis Order Transformations In Ni-Mo Alloys, Ovidiu F. Toader

Dissertations

No abstract provided.

Essays On Monetary Policy In Bangladesh, Sayera Younus

Dissertations

No abstract provided.

Programming Language Trends : An Empirical Study, Yaofei Chen

Dissertations

Predicting the evolution of software engineering technology trends is a dubious proposition. The recent evolution of software technology is a prime example; it is fast paced and affected by many factors, which are themselves driven by a wide range of sources. This dissertation is part of a long term project intended to analyze software engineering technology trends and how they evolve. Basically, the following questions will be answered: How to watch, predict, adapt to, and affect software engineering trends?

In this dissertation, one field of software engineering, programming languages, will be discussed. After reviewing the history of a group of …

Ip Traceback With Deterministic Packet Marking Dpm, Andrey Belenky

Dissertations

In this dissertation, a novel approach to Internet Protocol (IP) Traceback - Deterministic Packet Marking (DPM) is presented. The proposed approach is scalable, simple to implement, and introduces no bandwidth and practically no processing overhead on the network equipment. It is capable of tracing thousands of simultaneous attackers during a Distributed Denial of Service (DDoS) attack. Given sufficient deployment on the Internet, DPM is capable of tracing back to the slaves for DDoS attacks which involve reflectors. Most of the processing is done at the victim. The traceback process can be performed post-mortem, which allows for tracing the attacks that …

Capacity, Coding And Interference Cancellation In Multiuser Multicarrier Wireless Communications Systems, Christian Ibars Casas

Dissertations

Multicarrier modulation and multiuser systems have generated a great deal of research during the last decade. Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier modulation generated with the inverse Discrete Fourier Transform, which has been adopted for standards in wireless and wire-line communications. Multiuser wireless systems using multicarrier modulation suffer from the effects of dispersive fading channels, which create multi-access, inter-symbol, and inter-carrier interference (MAI, ISI, ICI). Nevertheless, channel dispersion also provides diversity, which can be exploited and has the potential to increase robustness against fading. Multiuser multi-carrier systems can be implemented using Orthogonal Frequency Division Multiple Access (OFDMA), a …

Optimal And Intelligent Decision Making In Sustainable Development Of Electronic Products, Meimei Gao

Dissertations

Increasing global population and consumption are causing declining natural and social systems. Multi-lifecycle engineering and sustainable development address these issues by integrating strategies for economic successes, environmental quality, and social equity. Based on multi-lifecycle engineering and sustainable development concepts, this doctoral dissertation aims to provide decision making approaches to growing a strong industrial economy while maintaining a clean, healthy environment. The research develops a methodology to complete both the disassembly leveling and bin assignment decisions in demanufacturing through balancing the disassembly efforts, value returns, and environmental impacts. The proposed method is successfully implemented into a demanufacturing module of a Multi-LifeCycle …

Thermochemistry And Kinetic Analysis On Radicals Of Acetaldehyde + O2, Allyl Radical + O2 And Diethyl And Chlorodiethyl Sulfides, Jongwoo Lee

Dissertations

Thermochemical properties for reactants, intermediates, products and transition states important in the radicals of acetaldehyde + O₂ and allyl radical + O₂ reaction systems are analyzed with density functional and ab initic calculations, to evaluate the reaction paths and kinetics in oxidation and pyrolysis. Ketene is one important product resulting from acetaldehyde oxidation; thus thermochemistry plus isomerization and conversion reactions of ketene are also analyzed. Enthalpies of formation are determined using isodesmic reaction analysis at the CBSQ composite and density functional levels. Entropies and heat capacities are determined using geometric parameters and vibration frequencies obtained at the HF/6-31G(d') …

Thermochemistry And Kinetics In Pyrolysis And Oxidation Reaction Of Oxygenate Chlorocarbons, Neopentane, And Ortho-Xylene, Hongyan Sun

Dissertations

Thermochemical properties of chlorinated alcohols, chlorinated hydroperoxides and corresponding alkoxy, hydroxy alkyl radicals, peroxy and hydroperoxy alkyl radicals are determined by ab initlo and density functional calculations for modeling and optimization of complex chemical processes for combustion or incineration of chlorinated hydrocarbons. The entropy and heat capacities from vibrational, translational, and external rotational contributions are calculated by statistical mechanics, and the hindered rotational contributions to S^°₂₉₈ and C_p(T)'s are calculated by using direct integration over energy levels of the internal rotational potentials. The values of ΔH_f^°₂₉₈ are determined using isodesmic reactions …

Design And Evaluation Of A List Gathering Tool In A Web-Based Collaborative Environment, Yuanqiong Wang

Dissertations

This research focuses on how to build a "list" structure to combine individual items of information into some sort of structure that converts the individual items of information into a structure of knowledge relative to the problem. Software was designed to provide relationships among and comparisons of the contributions in a "list" structure, so that individual members of a group process will be able to understand the contributions of information made by the group as a whole.

A List Gathering Tool was designed and implemented, which is one component in a Web-based Social Decision Support System (SDSS) Toolkit. Then, a …

Performance Evaluation For Communication Systems With Receive Diversity And Interference, Debang Lao

Dissertations

Optimum combining (OC) is a well-known coherent detection technique used to combat fading and suppress cochannel interference. In this dissertation, expressions are developed to evaluate the error probability of OC for systems with multiple interferers and multiple receiving branches. Three approaches are taken to derive the expressions. The first one starts from the decision metrics of OC. It facilitates obtaining closed-form expressions for binary phase-shift keying modulation. The second approach utilizes the moment generating function of the output signal to interference plus noise ratio (SINR) and results in expressions for symbol and bit error probability for multiple phaseshift keying modulation. …

A Socio-Historical Analysis Of The Benton Harbor, Michigan Desegregation Case Between 1967 And 1981, Tiffany Anne Loftus Butzbaugh

Dissertations

This study focuses on the socio-history of the Benton Harbor Area School District's ("BHASD") desegregation froth 1967 when Berry v School District of TheCity of Benton Harbor , C.A. 9 W.D. Mich. (1967) ("Berry ") was filed until 1981, when the court-ordered busing took effect. The purpose is to write a socio-historical analysis of BHASC Board of Education (BHASC Board) decisions regarding racial balance and imbalance in BHASC schools. Specifically, I study theBHASD Board, the administration, and the community concerning the following socio-historically relevant decisions: (1) the transfer of students from theSodus attendance district in the BHASD to the …

Foreign Direct Investment In Developing Countries: Uncertainty, Trade And Welfare, Adugna Lemi

Dissertations

The objectives of this three-essay thesis are first, to analyze the role of economic and political uncertainty in affecting FDI flows; second, to test competing hypotheses that explain the determinants of sales of affiliates of U.S. multinational firms to alternative destinations; and third, to investigate the welfare impact of FDI flow on local firms in a host country. These issues are interrelated, as uncertainty is one of the main impediments in developing countries to attract foreign direct investment, and uncertainty in turn affects business practices of foreign affiliates in a host country. The combined effects of uncertainty and business practices …

The Effect Of Alcohol On Women’S Detection Of Risk In A Date Rape Analogue, Marci Marroquin Loiselle

Dissertations

Research strongly suggests that alcohol is a risk factor for date rape for both victims and perpetrators (Abbey, 1991, Fritner & Rubinson, 1994; Miller & Marshall, 1987; Muehlenhard & Linton, 1987; Norris & Cubbins, 1992; Marx, Van Wie, & Gross, 1996). Many victims of sexual assault consume alcohol prior to being raped (Marx, et al., 1999), and "early recognition of when a social situation with a male acquaintance or intimate partner has become threatening can aida woman in preventing a serious incident of sexual aggression" (Norris, et al, 1999, p. 230). This study's purpose was to experimentally address the link …

Male And Female He Created Them: Ælfric’S Lives Of Saints And Patristic Theories Of Gender, Rhonda L. Mcdaniel

Dissertations

My dissertation researches the writings of the four Latin Doctors, Ambrose, Jerome, Augustine, and Gregory the Great, in order to challenge the scholarly stereotype of misogyny and anxiety about women in the writings of these influential figures and, more importantly, to build the cultural foundation upon which to base an interpretation of Ælfric’s portrayals of male and female saints in the Lives of Saints.

Accordingly, in the first chapter I focus on the writings of the Latin Doctors concerning the practice of virginity and on their explications of the Trinity and the Creation and Fall of humankind. I then trace …

Spearman Rank Regression, Jason C. Parcon

Dissertations

The main purpose of this dissertation is to obtain an estimate of the slope parameter in a regression model that is robust to outlying values in both the x - and Y-spaces. The least squares method, though known to be optimal for normal errors, can yield estimates with infinitely large MSE's if the error distribution is thick-tailed. Regular rank-based methods like the Wilcoxon method are known to be robust to outlying values in the Y -space, but it is still grossly affected by outlying values in x -space.

This dissertation derives an estimate of the slope from an estimating …

Double Photoionization Of Atoms, Marco Wiedenhoeft

Dissertations

Double photoionization studies of atoms and molecules are new state-of-the-art studies providing a deeper knowledge of multi-electron excitations. This typeof work advances the understanding of many-body problems. Double photoionization of atoms is of great interest to learn about electron-electron correlation and relaxation effects in atoms and molecules. In order to study double photoionization processes, a new electron-electron coincidence apparatus was built to carry out the measurements. I will present the apparatus I built as well as the results of the measurement of the triply-differential-cross-section (TDCS) for the predicted interference and Post-Collision-Interaction (PCI) effects in the Xenon N₅O_{2,3 …}

Inroads Toward Contemporary Latina Literature: Poetry And Criticism, Adela Josefina Najarro

Dissertations

No abstract provided.

Reliability Of The Educational Technology Profiler Survey As A Method Of Gathering Information In Teacher Preparation Programs, Carmen A. Cornieles

Dissertations

Education is an important factor in the introduction of technology as tools to be used in the teaching process. Teacher preparation programs for general education and special education are working to ensure that technology is a common denominator method of instruction following standards from teaching accrediting agencies. Institutions in charge of teacher preparation programs are aware of the need to prepare their students effectively and efficiently in the use of technology to support teaching and learning. Students in teacher preparation programs should become knowledgeable on using educational technology in their everyday instruction when placed in a school. For this reason, …

A Guide For Conducting Teachers: Physical Movement Taught In Six Selected Instrumental Conducting Textbooks And An Annotated Bibliography, William Geoffrey Carlton

Dissertations

The purpose of the dissertation was to provide a comparative guide of conducting textbooks for conducting teachers and students. In order not to replicate M. Johnson's (1967) dissertation only instrumental conducting textbooks available to conducting teachers and students between 1967 and 1997 were considered. The survey determined that the most common area emphasized by textbook authors was physical movement. Six textbooks by the following authors were selected for comparison of approaches to physical movement: E. A.H. Green (1997), D. Hunsberger and R. E. Ernst (1992), D. Kohut and J. W. Grant (1990), J. A. Labuta (1995), B. McElheran (1989), and …

Job Satisfaction, Leadership Styles, And Teaching Practices Among Cnmi Public Elementary School Teachers, Charles J. Algaier Edd

Dissertations

This study investigated whether teacher leadership styles and teaching practices influenced teacher job satisfaction among public elementary school teachers in the Commonwealth of the Northern Mariana Islands. The study answered the following questions: (1) what is the level of job satisfaction among public elementary school teachers in the CNMI; (2) to what extent do CNMI teachers fall into the personal leadership style categories of transactional or transformational; (3) to what extent do CNMI public school teachers prefer either didactic or constructivist teaching practices; (4) to what extent do demographic factors, preferred leadership styles, and preferred teaching practices affect the degree …

Group Processes In Group Supervision: A Quantitative And Qualitative Study, Jeremy M. Linton

Dissertations

Although group supervision is widely employed with counselors during their training (Holloway & Johnston, 1985; Prieto, 1998) little research concerning its practice has been offered in the literature. The fact that group supervision practices appear to be based on assumptions that lack empirically-based support has led some researchers to raise ethical concerns regarding its continued use (Hess, 1997; Prieto, 1996). In particular, many have raised concerns regarding counselor educators and supervisors' lack of understanding regarding the role of group processes in group supervision. Accordingly, this exploratory studysought to investigate counselor-trainees' experiences of group processes in group supervision. The study also …

Effects Of Writing Therapy Across Ptsd And Chronic Stress, Jennifer E. Lewis

Dissertations

Research supports the effectiveness of writing therapy in reducing physical health problems and increasing positive feelings (Pennebaker & Beall, 1986). More recently, research indicates that writing about traumatic experiences is as effective as EMDR in reducing symptoms of Post Traumatic Stress Disorder (Largo-Marsh & Spates, 1997). The current study assessed the treatment efficacy of writing therapy for individuals with varying degrees of stress related symptoms. Specifically, this study examined writing treatment for Post-Traumatic Stress Disorder and work-related chronic stress or "burnout."

The study utilized a pretest-posttest comparison group design. Repeated measurements !)n primary dependent variables were collected at pretest through …

Investigation Of The Iced Flowfield Characteristics Related To The Stall Margin Instrumentation Used In Icing Conditions, Erik Pederson

Dissertations

The purpose of this dissertation is to investigate the relationship between the flowfield surrounding an iced airfoil and the stall margin instrumentation developed for use in icing conditions. The stall margin system indicates to the pilot the change in available lift due to ice accretions on the leading edge of an airfoil. This system displays the change in the form of a normalized lift coefficient. Four pressure ports are chosen to specifically maintain a constant calibration curve, for pressure versus normalized lift coefficient, regardless of ice shape. This allows these pressures to be used to determine the change in maximum …