Digital Commons Network^™

Spatial Distribution Of Global Runoff And Its Storage In River Channels, Balazs M. Fekete

Doctoral Dissertations

The present dissertation attempts to improve our current understanding of some of the key elements of the surface runoff and its horizontal transfers in rivers. The dissertation presents an intensive analysis of the uncertainties in water balance calculations and the impact of uncertainties in the input data and the formulation of the water balance calculations on the runoff estimate. A simple technique is presented to combine observed river discharge and simulated runoff to derive accurate estimates of the spatially distributed runoff. Such composite runoff estimates are valuable for numerous earth science and water resource studies.

The dissertation also discusses the …

Making Connections: Compartmentalization In Pre -Calculus Students' Understanding Of Functions, Hope H. Gerson

Doctoral Dissertations

Students develop knowledge constructs that they build into concepts through their experiences. Students demonstrate compartmentalization when they understand a construct or concept within one representation, but not another, or when they do not connect mathematically related ideas. For instance, a student may understand f(x) to mean plug x into the function within a symbolic representation, but the same student may understand f(x) to mean f times x within a tabular representation. A student with these understandings has a compartmentalized understanding of function notation.

A two-month study was conducted with a class of pre-calculus students enrolled in a parochial high school. …

The Level Of Teacher Involvement In The Vermont Mathematics Portfolio Assessment Process And Instructional Practices In Grade 4 Classrooms, Carol Anne Fritz

Doctoral Dissertations

The comprehensive assessment system in Vermont includes student mathematics portfolios that are submitted to the state Department of Education for scoring. A student portfolio should include 5--7 pieces of best work selected by the student that can be scored. This alternative assessment process has been in place for ten years, but limited information has been available from classroom teachers about the instructional practices they use when teaching mathematics, or whether or not those practices have been influenced by the portfolio process.

The study was developed to answer questions about the instructional practices used by teachers. Teachers' responses were compared to …

Non-Adiabatic Features In Magnetotail Fast Flows: Orbit Tracing And Data Comparisons, Bryan Michael Boll

Doctoral Dissertations

The purpose of this study is to investigate velocity space distribution functions in space plasmas. Orbit tracing methods are used to generate self-consistent models of several different magnetic and electric field configurations. Fast flows in the magnetotail are selected to be modeled using a relatively thin current sheet compared with quiet times. Four different electric fields are imposed, varying in characteristic thickness and magnitude. Using these four particle based models we were able to generate velocity distribution functions that show clear evidence of non-adiabatic features that depend on the electric field characteristic width. Several years of Geotail Comprehensive Plasma Instrumentation …

Relational Learning For A Sustainable Future: An Eco -Spiritual Model, Mary Elizabeth Westfall

Doctoral Dissertations

We are facing unprecedented environmental challenges as we enter the new millennium as human choices and practices have repeatedly led to environmental degradation. Increasingly there are individuals and groups seeking to address this environmental crisis and move toward more sustainable patterns of living. But in order to make alternative choices it will be essential to draw upon the wealth and variety of human capabilities.

For nearly 350 years Western culture has looked to reason and rationality to provide truth and direction. The affective side of being human, feelings, intuition, love, care, wonder, mystery and hope have largely been devalued. In …

Reflexivity, Elementary Operators And Cohomology, Jiankui Li

Doctoral Dissertations

Let H be a separable complex Hilbert space and let B(H) be the set of all bounded operators on H. In this dissertation, we show that if S is a n-dimensional subspace of B( H), then S is [ 2n ]-reflexive, where [t] denotes the largest integer that is less than or equal to t.

We obtain some lattice-theoretic conditions on a subspace lattice L which imply alg L , is strongly rank decomposable. Let S be either a reflexive subspace or a bimodule of a reflexive algebra. We find some conditions such that T has a rank one summand …

Detection Of Giardia Lamblia And Cryptosporidium Parvum In The Eastern Oyster (Crassostrea Virginica) Harvested From The Great Bay Estuary, Kim Marie Stowell

Doctoral Dissertations

The Great Bay Estuarine system is being impacted by point source and nonpoint source pollution that affect shellfish quality. Many outbreaks of human gastroenteritis are potentially caused by the consumption of raw or undercooked oysters in which the protozoan pathogens, Giardia lamblia and Cryptosporidium parvum are present. The development of a rapid and sensitive technique to detect infectious protozoa in oysters is a necessity.

Immunofluorescence has been employed as a technique for the detection of these organisms in drinking water. Cross reactivity with algae and the production of false positive results limits the usefulness of this technique in environmental studies. …

Physics Experiences And Calculus: How Students Use Physics To Construct Meaningful Conceptualizations Of Calculus Concepts In An Interdisciplinary Calculus /Physics Course, Karen Ann Marrongelle

Doctoral Dissertations

The purpose of this study was to investigate the manner by which students enrolled in an integrated Calculus/Physics course use their understanding of physics to inform their conceptualizations of calculus concepts. This study utilized a multiple case study design with analysis by and across cases. The cases represent eight first year students in the College of Engineering and Physical Sciences at the University of New Hampshire who enrolled in an integrated calculus/physics program. Data was gathered in a three-part process: (1) Semi-structured task-based interviews, (2) Participant-observation in the calculus/physics course, and (3) Obtaining copies of students' in-class notes, in-class activities, …

Numerical Simulation Of Acoustic Waves In A Rectangular Chamber, Normah Mohd. Ghazali

Doctoral Dissertations

Numerical simulation of acoustic waves in a closed two-dimensional rectangular chamber is considered. The waves are generated by a membrane or piston boundary condition on one wall. The simulations are performed through many acoustic cycles. A stack of heat exchanger plates are sometimes included. The study is motivated by thermoacoustic refrigeration, a phenomena which uses soundwaves in a chamber to achieve a cooling effect.

The present study treats the flow numerically. The governing equations are the viscous compressible Navier-Stokes system, assuming a perfect gas. The numerical method employs a finite difference spatial discretization and semi-implicit time-marching procedure. Verification is accomplished …

Multi -Mission Attitude Determination System For Balloon Flight, Liping Mo

Doctoral Dissertations

MADS (Multi-mission Attitude Determination System) is a new software package used to determine the attitude of instruments on a high-altitude balloon employed for scientific experiments. There is no existing system for the automated determination of the attitude of instruments in balloon experiments, so we have developed MADS to do the data analysis for balloon experiments to find the location of astrophysical sources such as gamma-ray or x-ray sources.

The two areas that required most work were modeling star trackers and modeling the motion of the balloon. Star trackers are used on satellites, but are far too expensive and sophisticated to …

Mathematical Modeling For Fabricating A Microstructure With A Pre-Specified Geometry Using Laser -Induced Chemical Vapor Deposition, Chaoyang Zhang

Doctoral Dissertations

Laser-induced chemical vapor deposition (LCVD) is an emerging new technique with many practical applications. To optimize the system for fabricating a microstructure with a pre-specified geometry in pyrolytic LCVD, a three-dimensional mathematical model is developed for predicting temperature distributions and laser dwell times across the substrate scanned by the laser beam. A microstructure is fabricated layer by layer, and for each layer the laser beam moves from one pixel to the next. The complicated correlations among temperature distribution, deposit growth rate, and laser dwell time are investigated. A purely heterogeneous reaction is assumed and any gas-phase transport is ignored.

A …

A Study Of Mathematics Course Sequence And Student Performance In Mathematics In A Block Scheduled High School, John Harvell Moody

Doctoral Dissertations

The 1983 study of the condition of American Education, A Nation at Risk, brought a significant amount of attention to the way in which schools provided students with the skills necessary to be productive citizens. Many of the recommendations contained in A Nation at Risk focused on the perceived poor performance of American students when compared to their counterparts worldwide. The year after publication of A Nation at Risk, the National Commission on Time and Learning published Prisoners of Time, a report that called for the establishment of high academic standards for students and a major restructuring of the school …

Learning And Understanding In Abstract Algebra, Bradford Reed Findell

Doctoral Dissertations

Students' learning and understanding in an undergraduate abstract algebra class were described using Tall and Vinner's notion of a concept image, which is the entire cognitive structure associated with a concept, including examples, nonexamples, definitions, representations, and results. Prominent features and components of students' concept images were identified for concepts of elementary group theory, including group, subgroup, isomorphism, coset, and quotient group.

Analysis of interviews and written work from five students provided insight into their concept images, revealing ways they understood the concepts. Because many issues were related to students' uses of language and notation, the analysis was essentially semiotic, …

Children's Song-Makers As Messengers Of Hope: Participatory Research With Implications For Teacher Educators, Peter J. Baird

Doctoral Dissertations

Pete Seeger, Ella Jenkins, Suni Paz and six other leading children's musicians in the U.S contributed their experience to this study about the crucial role of music and singing for social justice in children's lives and its shrinking presence in U.S. pre-school and elementary schools. The study built its theoretical framework on arts and music education, transformative education, and folk and socially conscious children's music. Participatory research, based on the revolutionary education theories of Paulo Freire, guided the dialogues with the participants. These activist singer-songwriters were asked how they define social justice, how they involve children in singing, and what …

Searches For Neutral Higgs Bosons In Quark-Antiquark Tau-Antitau Final States Using The Opal Detector At Lep, James Andrew Hocker '91

Doctoral Dissertations

Searches for neutral Higgs bosons have been performed with the OPAL detector at LEP. Approximately 170 /pb of e+e- collision data at a center-of-mass energy of 189 GeV have been used to search for the SM process e+e- to HZ as well as for the processes e+e- to hZ and e+e- to hA which occur in extended Higgs theories. The searches are sensitive to final states containing quarks and tau leptons, for which an artificial neural network for the identification of tau leptons was designed. The results have been combined with OPAL searches for other final states to obtain a …

The Importance Of Communication Skills: Perceptions Of Is Professionals, Is Managers, And Users, Ruth A. Spurlock Miller

Doctoral Dissertations

Information systems (IS) research has shown that communication skills tend to be more important than technical skills to IS staff in project development activities. Yet, research findings indicate that IS staff are lacking in the communication skills they need to interact successfully with users and managers during systems development. Thus, the two purposes of this research were (1) to determine whether IS staff, IS managers, and IS users differ in their perceptions of important communication skills that IS staff need and (2) if differences do exist, to assess the impact of the differences on user satisfaction with IS product and …

Fluid Flow In Micro-Channels: A Stochastic Approach, Hilda Marino Black

Doctoral Dissertations

In this study free molecular flow in a micro-channel was modeled using a stochastic approach, namely the Kolmogorov forward equation in three dimensions. Model equations were discretized using Central Difference and Backward Difference methods and solved using the Jacobi method. Parameters were used that reflect the characteristic geometry of experimental work performed at the Louisiana Tech University Institute for Micromanufacturing.

The solution to the model equations provided the probability density function of the distance traveled by a particle in the micro-channel. From this distribution we obtained the distribution of the residence time of a particle in the micro-channel. Knowledge of …

Effect Of Cooperative Learning (Student Teams -Achievement Divisions) On African American And Caucasian Students' Interracial Friendships, James Edward Cook

Doctoral Dissertations

The purpose of this study was to gauge the impact of cooperative learning teams on interracial friendships. The participants were 256 sixth, seventh, and eighth grade students in English classes (20% African American and 80% Caucasian) at a rural middle school in Louisiana. After delivery of instruction, the experimental group studied worksheets in teams, received rewards based upon the team's performance, and received individual grades based upon individual exam scores. The control group studied worksheets individually and received individual grades. This eight week study utilized the sociometric question, “Who are your friends in this class?” as the pretest and posttest …

An Empirical Analysis Of Taxpayers' Attitudes And Behavioral Intentions Regarding Compliance With Federal Income Tax Laws, Stanley Wayne Hays

Doctoral Dissertations

The purpose of this study was to analyze variables that potentially affect taxpayers' attitudes about income tax compliance. Phase one of the study focused on the relationships between four groups of variables and ethical perceptions of compliance behaviors. The four groups of variables follow: demographic variables such as age, education, and household income; personal characteristic variables such as idealism, relativism, conservatism, and religiosity; situational variables including an overall attitude about paying federal income taxes and impressions of the effectiveness of a number of law changes intended to make the IRS more responsive; and, consequential variables comprised of five dimensions of …

Swarm Engineering, S. Kazadi '90

Doctoral Dissertations

Swarm engineering is the natural evolution of the use of swarm-based techniques in the accomplishment of high level tasks using a number of simple robots. In this approach, one seeks not to generate a class of behaviors designed to accomplish a given global goal, as is the approach typically found in mainstream robotics. Once the class of behaviors has been understood and decided upon, specific behaviors designed to accomplish this goal may be generated that will complete the desired task without any concern about whether or not the final goal will actually be completed. As long as the generated behaviors …

A Hybrid Finite Element-Finite Difference Method For Thermal Analysis In A Double-Layered Thin Film, Teng Zhu

Doctoral Dissertations

Thin film technology is of vital importance in microtechnology applications. For instance, thin films of metals, of dielectrics such as SiO2, or Si semiconductors are important components of microelectronic devices. The reduction of the device size to the microscale has the advantage of enhancing the switching speed of the device. The reduction, on the other hand, increases the rate of heat generation that leads to a high thermal load on the microdevice. Heat transfer at the microscale with an ultrafast pulsed-laser is also a very important process for thin films. Hence, studying the thermal behavior of thin films or of …

The Effects Of Structured One-On-One Tutoring In Sight Word Recognition Of First-Grade Students At-Risk For Reading Failure, Laureen Goers Mayfield

Doctoral Dissertations

The purpose of this study was to determine the effects of an alternative reading program on the performance of at-risk first graders. Sixty first graders from three north Louisiana public elementary schools with high poverty rates, who were determined by their teachers and principals to be functioning in the bottom 20 to 30% of first grade reading students, were purposefully selected. Students were pretested on three subtests of the Woodcock Reading Mastery Test-Revised (WRMT-R), Form G: Letter Identification, Word Identification, and Word Attack. Participants were randomly assigned to either a control or an experimental group. Experimental group students received 15 …

Cramer-Rao Bound And Optimal Amplitude Estimator Of Superimposed Sinusoidal Signals With Unknown Frequencies, Shaohui Jia

Doctoral Dissertations

This dissertation addresses optimally estimating the amplitudes of superimposed sinusoidal signals with unknown frequencies. The Cramer-Rao Bound of estimating the amplitudes in white Gaussian noise is given, and the maximum likelihood estimator of the amplitudes in this case is shown to be asymptotically efficient at high signal to noise ratio but finite sample size. Applying the theoretical results to signal resolutions, it is shown that the optimal resolution of multiple signals using a finite sample is given by the maximum likelihood estimator of the amplitudes of signals.

Efficient Algorithms And Implementations For Signal Processing, Changbai Xiao

Doctoral Dissertations

A scheme is presented to regain a finite number of lost samples from a Nyquist-rate-sampled band-limited signal f of finite energy by replenishing new sample values of the same number. The result can also be viewed as the solution to a special non-uniform sampling problem.

A scheme is also presented to recover a band-limited function f of finite energy from its sampling values on real sequences with an accumulation point. The result given here can also be viewed as an approach to the extrapolation problem of determination a band-limited function in terms of its given values on a finite interval. …

Bottom-Up Design Of Artificial Neural Network For Single-Lead Electrocardiogram Beat And Rhythm Classification, Srikanth Thiagarajan

Doctoral Dissertations

Performance improvement in computerized Electrocardiogram (ECG) classification is vital to improve reliability in this life-saving technology. The non-linearly overlapping nature of the ECG classification task prevents the statistical and the syntactic procedures from reaching the maximum performance. A new approach, a neural network-based classification scheme, has been implemented in clinical ECG problems with much success. The focus, however, has been on narrow clinical problem domains and the implementations lacked engineering precision. An optimal utilization of frequency information was missing. This dissertation attempts to improve the accuracy of neural network-based single-lead (lead-II) ECG beat and rhythm classification. A bottom-up approach defined …

Modeling The Friction Effects Of Eelgrass On The Tidal Flow In Great Bay, New Hampshire, Safak Nur Erturk

Doctoral Dissertations

In this study the frictional effects of eelgrass (Zostera marina L.) on the tidal flow in Great Bay, NH is modeled using a bottom friction coefficient adjustment approach. A two-dimensional, non-linear, time stepping, finite element model, ADAM is used. ADAM model incorporates two-dimensional wave physics, with a porous medium beneath the sediment surface to simulate wetting and drying process on the tidal flats. The effectiveness of ADAM model in simulating the tidal flow in Great Bay with wetting and drying on the tidal flats is verified. The model is calibrated by adjusting the bottom friction coefficient for the M2, M2S2 …

Exploring Other Worlds: Margaret Fox, Elisha Kane, And The Antebellum Culture Of Curiosity, David Alexander Chapin

Doctoral Dissertations

Antebellum Americans had a strong interest in the unknown, which manifested itself simultaneously in highbrow, middlebrow, and lowbrow culture. Venues such as scientific institutions, lyceums, lecture halls, the "penny-press," and the dime-museum all catered to American curiosity. Exploring Other Worlds examines this "culture of curiosity," arguing that curiosity was a defining trait of antebellum America, transcending many of the boundaries we often associate with the era. Curiosity promoted intellectual interest in science, but it also led to the sensationalism of modern commercial popular culture.

The inter-related lives of Elisha Kane and Margaret Fox demonstrate this thesis. Kane was America's first …

The Perceived Effects Of State -Mandated Testing In New Hampshire, Stephen A. Kossakoski

Doctoral Dissertations

The purposes of this study were: (1) to examine the perceptions of third grade teachers in the state of New Hampshire concerning the state's mandated testing program, and (2) to determine if there was a relationship between teachers' perceptions and their schools' socioeconomic status. The survey instrument designed for this study contained 61 closed response Likert scale items that measured teachers' perceptions regarding changes in curriculum and instruction, sources of pressure to improve test scores, and attitude toward the third grade test. A stratified random sample of 310 third grade teachers was selected to participate in this study. The percentage …

Piety, Politeness, And Power: Formation Of A Newtonian Culture In New England, 1727--1779, Frances Herman Lord

Doctoral Dissertations

This dissertation explores how men and women deployed the mathematical and experimental science of Isaac Newton and the new science based upon his work as the framework for a "Newtonian culture" in New England between 1727 and 1779, which established our modern view of the natural world and the authority of science. Their endeavors often involved co-opting the authority, and the cachet, of Newton's name and redirecting it toward new ends that involved both the affirmation and challenge of prevalent cultural, religious, and social values. This study examines the uses of Newtonian natural philosophy within the context of the cultural …

Mathematics And Socio -Cultural Behavior: A Case Study Of The Enculturation Of A New Mathematician, Timothy Byron Gutmann

Doctoral Dissertations

Research has shown that mathematics as we know it is a product of the socio-cultural climate in which it was developed. This research attempts to address the related question of how being involved in mathematics influences the socio-cultural lives of mathematicians. A new Ph.D. mathematician hired in his first faculty position was observed for a period of 13 weeks, most during his first semester. Analysis of this long-term, in depth case study followed ethnographic methods and drew on theories of rites of passage, organizational socialization, self-identity, and evolution. The role of mathematics in the departmental culture and in the newcomer's …