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1997

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Reverse Engineering Of Aircraft Wing Data Using A Partial Differential Equation Surface Model, Jacalyn M. Huband Jul 1997

Reverse Engineering Of Aircraft Wing Data Using A Partial Differential Equation Surface Model, Jacalyn M. Huband

Mathematics & Statistics Theses & Dissertations

Reverse engineering is a multi-step process used in industry to determine a production representation of an existing physical object. This representation is in the form of mathematical equations that are compatible with computer-aided design and computer-aided manufacturing (CAD/CAM) equipment. The four basic steps to the reverse engineering process are data acquisition, data separation, surface or curve fitting, and CAD/CAM production. The surface fitting step determines the design representation of the object, and thus is critical to the success or failure of the reverse engineering process. Although surface fitting methods described in the literature are used to model a variety of …


High-Order Finite-Difference Schemes And Their Application To Computational Acoustics, Joe Leo Manthey Jul 1997

High-Order Finite-Difference Schemes And Their Application To Computational Acoustics, Joe Leo Manthey

Mathematics & Statistics Theses & Dissertations

The primary focus of this study is upon the numerical stability of high-order finite-difference schemes and their application to duct acoustics. Since acoustic waves are known to be non-dissipative and non-dispersive, high-order schemes are favored for their low dissipation and low dispersion relative to the low-order schemes. The primary obstacle to the the development of explicit high-order finite-difference schemes is the construction of boundary closures which simultaneously maintain the formal order of accuracy and the numerical stability of the overall scheme. In this thesis a hybrid seven-point, fourth-order stencil for computing spatial derivatives is presented and the time stability is …


Investigation Of Drag Reduction On A Two-Dimensional Circular Cylinder By Ejecting Jet From The Rear Stagnation Region, Satoshi Atsuchi Jul 1997

Investigation Of Drag Reduction On A Two-Dimensional Circular Cylinder By Ejecting Jet From The Rear Stagnation Region, Satoshi Atsuchi

Mechanical & Aerospace Engineering Theses & Dissertations

Extensive work in the field of drag reduction has been done in the past. However, this field of study is highly desirable today because of various high-speed research programs. The present study attempts to investigate the feasibility of drag reduction on a cylinder by flow injection from the rear stagnation region. A two-dimensional circular cylinder at Reynolds number l x105with a jet ejected from its tail is selected as a physical model. To tackle this problem, a numerical simulation as well as an experimental approach were used. Despite the recent development of computational fluid dynamics (CFD), computing a …


A Study Of The "Pride" Program: A Residential, Summer-School Program For At-Risk Middle-School Students In An Urban Community, Maria Teresa Amillategui Grimm Jul 1997

A Study Of The "Pride" Program: A Residential, Summer-School Program For At-Risk Middle-School Students In An Urban Community, Maria Teresa Amillategui Grimm

Theses and Dissertations in Urban Services - Urban Education

This research examined the Pride Program (1991 and 1992)--a residential, summer-school program for at-risk middle-school students. It was conducted with subjects from two large, urban middle schools for the purpose of determining if, after five school years, differences existed among three selected groups (treatment, control and comparison) of at-risk students in the areas of academic achievement, attendance and conduct. Treatment-group self-esteem was examined over a three-year period. Furthermore, this study provided a qualitative program evaluation of the Pride Program for the first two years of its existence.

The results are as follows: The qualitative evaluation indicated that all participants were …


Evaluation Of Solid Phase Extraction Followed By Supercritical Fluid Elution Of Semi-Volatile Organic Compounds In Toxicity Characteristic Leachates, William Edward Corl Iii Jul 1997

Evaluation Of Solid Phase Extraction Followed By Supercritical Fluid Elution Of Semi-Volatile Organic Compounds In Toxicity Characteristic Leachates, William Edward Corl Iii

Chemistry & Biochemistry Theses & Dissertations

The Environmental Protection Agency (EPA) developed the toxicity characteristic leaching procedure (TCLP) to determine the potential for unknown wastes to leach haz.ardous constituents into the environment. Methods currently being used for the extraction of semi-volatile organic compounds from aqueous TCLP leachates involve acid/base partitioning into methylene chloride. The concentrated extract is then analyzed by gas chromatography/mass spectrometry (GC/MS). The methods are either timeconsuming or labor intensive and they generate significant volumes of haz.ardous wastes themselves. Considering the haz.ards and disposal costs of methylene chloride wastes, great interest has been elicited by the EPA in other extraction techniques which would reduce …


Speciation Of Selenium In Serum, Alice Tsapayi-Musapatike Jul 1997

Speciation Of Selenium In Serum, Alice Tsapayi-Musapatike

Chemistry & Biochemistry Theses & Dissertations

We investigated the separation of selenoprotein P and extracellular (serum) glutathione peroxidase using a concanavalin A affinity column. We were able to show that the method does not adequately separate serum glutathione peroxidase from selenoprotein P because human glutathione peroxidase binds strongly to the column. We also found that albumin can interfere with measurement serum of glutathione peroxidase activity when hydrogen peroxide is used as the substrate. When t-butyl hydroperoxide was used as the substrate, less than 10% of the measured activity was due to the presence of albumin. We also found that the pH of the elution buffer plays …


Fabrication And Evaluation Of Boron-Doped Cvd Diamond Microelectrodes, Song Pang Jul 1997

Fabrication And Evaluation Of Boron-Doped Cvd Diamond Microelectrodes, Song Pang

Chemistry & Biochemistry Theses & Dissertations

The electrochemical behavior of boron-doped diamond microelectrodes has been studied in acetonitrile solutions containing two redox couples using cyclic voltammetry. One test system is 1-2.5 mM ferrocene, containing 0.1 M Tetrabutyl ammonium hexafluorophosphate (TBAH). This well-known reversible redox system involves only one electron transfer with little or no change in the solvation sphere and no breakage/formation of chemical bonds. Another test system is a 1 mM S2Mo180644- solution containing 0.1 M HCIO4. This is one of the most complicated redox systems. In the presence of acid, electrons are usually transferred consecutively and …


Searching For Zarathustra: A Nietzschean Critique Of Post-Traditional Ethical Theory, Joshua Knutsen Jul 1997

Searching For Zarathustra: A Nietzschean Critique Of Post-Traditional Ethical Theory, Joshua Knutsen

Institute for the Humanities Theses

Following Friedrich Nietzsche's critique of ethics, twentieth century philosophical investigations into ethics have attempted to abandon the universalist principles which guided the endeavors of Christianity, Kant and Bentham. The purpose of this work was to examine exactly how successful that endeavor has been. In order to represent the field of ethics as a whole given the limited space of the work I chose three distinct ethics, which in their formulations are representative of the current ethical clime. Jean-Paul Sartre's existentialism serves as a model for radical individualism and solipsism. Alasdair MacIntyre' s virtue based ethic demonstrates communitarian trends. And the …


The Use Of Operator Regularization In The Computation Of Effective Field Theories, Jeffrey M. Hersh Jul 1997

The Use Of Operator Regularization In The Computation Of Effective Field Theories, Jeffrey M. Hersh

Physics Theses & Dissertations

Current methods of computing low-energy effective field theories while being accurate are extremely cumbersome co implement. Operator regularization provides a way to calculate any desired effective field theory avoiding the tediousness of previous methods. This technique is shown to be an effective method in explicitly calculating the 1/mheavy corrections that match an original full theory to its low-energy effective counterpart. This is demonstrated up to two loop order for the case of a charged two field θ{4}{4} theory as well as up to one loop order for the Higgs sector of the Minimal Supersymmetric Model. Additionally, the renormalization …


A Comparison Between Simulated And Measured Free-Flight Vortex Encounter Behavior In The Nasa Langley Full-Scale Wind Tunnel, Robert A. Pfouts Jul 1997

A Comparison Between Simulated And Measured Free-Flight Vortex Encounter Behavior In The Nasa Langley Full-Scale Wind Tunnel, Robert A. Pfouts

Mechanical & Aerospace Engineering Theses & Dissertations

An examination of the use of static measurements in simulating dynamic aircraft­ wake encounters is presented. By comparing dynamic aircraft-wake vortex encounter measurements obtained in free-flight wind tunnel tests to data obtained from computer­ simulated encounters based on static wind tunnel data, a determination is made concerning the validity of static vortex models in a dynamic flight environment. The development and testing of specialized elements of a flight simulation code are presented and dynamic free-flight measurements and predicted results are compared.

This study shows that static modeling provides reasonable estimates for lateral encounter trajectories when the following aircraft model is …


Punitive Damages, Social Norms, And Economic Analysis, Robert D. Cooter Jul 1997

Punitive Damages, Social Norms, And Economic Analysis, Robert D. Cooter

Law and Contemporary Problems

Cooter offers an economic analysis of punitive damages, keeping in mind the role of social norms. Liability for compensatory damages provides efficient incentives for self-monitoring.


Of Characterization And Other Matters: Thoughts About Multiple Damages, G. Robert Blakey Jul 1997

Of Characterization And Other Matters: Thoughts About Multiple Damages, G. Robert Blakey

Law and Contemporary Problems

Blakey argues that economic analysis in the courts must be substantially supported by other insights, say from ethics or history.


Philosophia, Adriaan Theodoor Peperzak Jul 1997

Philosophia, Adriaan Theodoor Peperzak

Faith and Philosophy: Journal of the Society of Christian Philosophers

No abstract provided.


Calculation Of Heavy Ion Inactivation And Mutation Rates In Radial Dose Model Of Track Structure, Francis A. Cucinotta, John W. Wilson, Mark R. Shavers, Robert Katz Jul 1997

Calculation Of Heavy Ion Inactivation And Mutation Rates In Radial Dose Model Of Track Structure, Francis A. Cucinotta, John W. Wilson, Mark R. Shavers, Robert Katz

Robert Katz Publications

In the track structure model, the inactivation cross section is found by summing an inactivation probability over all impact parameters from the ion to the sensitive sites within the cell nucleus. The inactivation probability is evaluated by using the dose response of the system to gamma rays and the radial dose of the ions and may be equal to unity at small impact parameters. We apply the track structure model to recent data with heavy ion beams irradiating biological samples of E. Coli, Bacillus Subtilis spores, and Chinese hamster (V79) cells. Heavy ions have observed cross sections for inactivation that …


After The Dna Wars: Skirmishing With Nrc Ii, Richard O. Lempert Jul 1997

After The Dna Wars: Skirmishing With Nrc Ii, Richard O. Lempert

Articles

This article traces some of the controversies surrounding DNA evidence and argues that although many have been laid to rest by scientific developments confirmed in the National Research Council's second DNA report, there remain several problems which are likely to lead to continued questioning of standard ways prosecutors present DNA evidence. Although much about the report is to be commended, it falls short in several ways, the most important of which is in its support for presenting random match probabilities independent of plausible error rates. The article argues that although one can sympathize with the NRC committee's decision as an …


Measurement Of The Transverse Spin Correlations In The Decay Z → Τ+Τ-, Barate, R.; Et Al., M. Thulasidas Jul 1997

Measurement Of The Transverse Spin Correlations In The Decay Z → Τ+Τ-, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

A measurement of the transverse-transverse, CTT, and transverse-normal CTN, τ spin correlations in the decay Z0 → τ+ τ− is presented based on the aplanarity angle of the decay products of both taus. Based on 80 pb−1 of data collected by ALEPH[1] in 1992, 1993 and 1994 on the peak of the Z resonance, the results are: CTT = 1.00 ± 0.14(stat) ± 0.04(syst), CTN =−0.08 ± 0.14(stat) ± 0.02(syst). These values are in agreement with the Standard Model predictions, CTT = 0.989 and CTN = 0.


Thinking Of Mediation As A Complex Adaptive System, J.B. A. Ruhl Jul 1997

Thinking Of Mediation As A Complex Adaptive System, J.B. A. Ruhl

Vanderbilt Law School Faculty Publications

This article uses my work on complex adaptive systems to think about how litigation and mediation differ in terms of adaptive qualities, suggesting that mediation is indeed a more adaptive mode of dispute resolution in certain contexts.


In Search Of The Lost Chord: Reflections On The 1996 Item Veto Act, Neal Devins Jul 1997

In Search Of The Lost Chord: Reflections On The 1996 Item Veto Act, Neal Devins

Faculty Publications

No abstract provided.


Theoretical Underpinnings Of Service Learning, Rebecca Lynn Carver Jul 1997

Theoretical Underpinnings Of Service Learning, Rebecca Lynn Carver

Service Learning, General

Although the merits of service learning frequently rest on how well it can be argued that the programs improve students' academic skills, this is only one of several outcomes that can result from implementing service learning programs. This article introduces readers to the full range of goals that service learning promises to achieve and to the specific principles that can be put into practice in order to meet these goals. Service learning consciously integrates students' experiences into the curriculum. As such it addresses the three major goals of "experiential education": allowing students to become more effective change agents, developing students' …


Choice Points:Creating Clinical Qualitative Research Studies, Paul V. Maione Jul 1997

Choice Points:Creating Clinical Qualitative Research Studies, Paul V. Maione

The Qualitative Report

Today, more psychotherapists are seeing the utility of studying their own and others' therapeutic work. With the growing popularity and acceptance of qualitative methods, the research process takes on special significance for the clinician/researcher. Using qualitative methodologies, therapists can conduct studies that are immediately relevant to their therapeutic work. In this paper, I discuss eight decisions or "choice points" clinician/researchers face when conducting clinical qualitative research studies. The choices I discuss are not all inclusive, yet they are representative of the choices most clinical qualitative projects required.


Chaos In The Clinic:Applications Of Choas Theory To A Qualitative Study Of A Veterinary Practice, Eleanor Craven Brennan Jul 1997

Chaos In The Clinic:Applications Of Choas Theory To A Qualitative Study Of A Veterinary Practice, Eleanor Craven Brennan

The Qualitative Report

This paper is the result of a twelve hour participant observation study of a local, private veterinary practice in southeastern Pennsylvania. Field notes and semi-structured interviews, the result of naturally occurring conversation between me and practice members, were taken over a twelve week period, one hour of site visit each week. Using a grounded theory methodology, categories of social interaction among veterinarians, veterinary technicians, clerical staff, owners and animal clients were assembled, discarded and re-assembled. The resulting categories were analyzed using the conceptual framework of chaos theory and the principles of uncertainty. It appears that the most striking feature of …


Joint-Transform Correlator Architecture For Wavelet Feature Extraction, Samuel Peter Kozaitis, Mark A. Getbehead, Wesley E. Foor Jul 1997

Joint-Transform Correlator Architecture For Wavelet Feature Extraction, Samuel Peter Kozaitis, Mark A. Getbehead, Wesley E. Foor

Electrical Engineering and Computer Science Faculty Publications

A version of an image consisting of multiple wavelet scales allows for more flexible feature extraction when compared to the use of one wavelet scale. We proposed an imaging system based on a multiple-input joint-transform correlator, that could be used for multiple wavelet-scale analysis of an input image. Given a single input image and wavelet, for m wavelet scales, m versions of the wavelet and m copies of the input image were generated using conventional optics that are used as inputs to a joint wavelet-transform correlator. The output consisted of 4 m - 1 correlation results, one of which is …


Critical Issues For Understanding Particle Acceleration In Impulsive Solar Flares, James A. Miller, Peter J. Cargill, A. Gordon Emslie, Gordon D. Holman, Brian R. Dennis, Ted N. La Rosa, Robert M. Winglee, Stephen G. Benka, S. Tsuneta Jul 1997

Critical Issues For Understanding Particle Acceleration In Impulsive Solar Flares, James A. Miller, Peter J. Cargill, A. Gordon Emslie, Gordon D. Holman, Brian R. Dennis, Ted N. La Rosa, Robert M. Winglee, Stephen G. Benka, S. Tsuneta

Faculty Articles

This paper, a review of the present status of existing models for particle acceleration during impulsive solar flares, was inspired by a week-long workshop held in the Fall of 1993 at NASA Goddard Space Flight Center. Recent observations from Yohkoh and the Compton Gamma Ray Observatory, and a reanalysis of older observations from the Solar Maximum Mission, have led to important new results concerning the location, timing, and efficiency of particle acceleration in flares. These are summarized in the first part of the review. Particle acceleration processes are then discussed, with;particular emphasis on new developments in stochastic acceleration by magnetohydrodynamic …


Physical Parameterization Of Stellar Spectra: The Neural Network Approach, Coryn A.L. Bailer-Jones, Ted Von Hippel, Mike Irwin, Gerard Gilmore Jul 1997

Physical Parameterization Of Stellar Spectra: The Neural Network Approach, Coryn A.L. Bailer-Jones, Ted Von Hippel, Mike Irwin, Gerard Gilmore

Publications

We present a technique which employs artificial neural networks to produce physical parameters for stellar spectra. A neural network is trained on a set of synthetic optical stellar spectra to give physical parameters (e.g. Teff, log g, [M/H]). The network is then used to produce physical parameters for real, observed spectra. Our neural networks are trained on a set of 155 synthetic spectra, generated using the spectrum program written by Gray (Gray & Corbally 1994, Gray & Arlt 1996). Once trained, the neural network is used to yield Teff for over 5000 B–K spectra extracted from a set of photographic …


Resuspension And Transport Of Fine Sediments By Waves, Chiang C. Mei, She-Jun Fan, Kang-Ren Jin Jul 1997

Resuspension And Transport Of Fine Sediments By Waves, Chiang C. Mei, She-Jun Fan, Kang-Ren Jin

OES Faculty Publications

Although waves are the primary cause of sediment resuspension in the nearshore zone, in existing theoretical models, long-scale currents induced by the mean wind are often taken to be the only agent for the diffusion and convection of resuspended sediments. We present here theoretical examples where waves play a direct role in all aspects of sediment transport. Details are given for the simple case where only waves are present; the wave-induced current and diffusivity are shown to be no less important than similar factors in the wind-driven current. Hence, in a comprehensive model, one should include not only the current …


Systematics Of The Freshwater Amphipod Genus Crangonyx (Crangonyctidae) In North America, Jun Zhang Jul 1997

Systematics Of The Freshwater Amphipod Genus Crangonyx (Crangonyctidae) In North America, Jun Zhang

Biological Sciences Theses & Dissertations

The systematics of the amphipod genus Crangonyx of North America (north of Mexico) is revised, based on available collections (ca. 2240) and literature dealing with the genus. A grand total of 42 North America species of Crangonyx are recognized in the present study, 24 of them new to science. All species are described or redescribed and figured, utilizing external morphological features. Keys to both species groups and individual species are given. Phylogenetic trees are built using computer programs (PAUP, Hennig86, MacClade) based on 26 characters. Wagner parsimony produced 18 parsimonious trees and Fitch parsimony produced 45 trees. The consensus tree …


Small Angle Neutron Scattering From Nanodroplet Aerosols, Barbara Ellen Wyslouzil, Janice L. Cheung, Gerald Wilemski, Reinhard Strey Jul 1997

Small Angle Neutron Scattering From Nanodroplet Aerosols, Barbara Ellen Wyslouzil, Janice L. Cheung, Gerald Wilemski, Reinhard Strey

Physics Faculty Research & Creative Works

We report the first measurements of small angle neutron scattering from an aerosol. The aerosol was produced by expanding a D2O-N2 vapor mixture in a supersonic Laval nozzle. The neutron wavelength (0.5 nm) is less than the typical particle size, and we can therefore derive the average particle size (5-8 nm), number density (~1012 cm-3), and polydispersity of the size distribution directly from the experimental data rather than by inferring them from complex models of particle formation and growth. We also predict and observe a Doppler shift-induced anisotropy in the scattering pattern due to …


Mark-Recapture Creel Survey And Survival Models, Shampa Saha Jul 1997

Mark-Recapture Creel Survey And Survival Models, Shampa Saha

Mathematics & Statistics Theses & Dissertations

In this dissertation, we consider a model based approach to the estimation of exploitation rate of a fish population by combining mark-recapture procedures with a creel survey. We also consider the analysis of a proportional hazards survival model for randomly censored observations, known as the Koziol-Green model. The model assumes that the lifetime survivor function is a power of the censored time survivor function.

In Chapter 2, we introduce the model based approach to the estimation of the exploitation rate of a fish population by combining mark-recapture procedures with a creel survey. We assume that in the beginning of a …


The Men Behind The Oath: A Profile Of The German Officer Corps In The Interwar Period, 1919-1939, Brian E. Crim Jul 1997

The Men Behind The Oath: A Profile Of The German Officer Corps In The Interwar Period, 1919-1939, Brian E. Crim

History Theses & Dissertations

The predominance of technocrats within the Reichswehr, the inability of the officer corps to reassert its elite status in the Weimar era, and the extensive interaction between the Reichswehr and a militaristic German society contributed to Hitler's successful absorption of military authority in the 1930s. The social and political upheaval resulting in part from the First World War diffused military authority and diminished the role of the officer corps in German society. The corps struggled to maintain its historic level of corporateness and consistently failed to fulfill its responsibility to the Weimar Republic. The Reichswehr's top officers worked to revitalize …


High-Performance Input/Output Circuit For Cmos Integrated Circuit Interface, Chee How Lim Jul 1997

High-Performance Input/Output Circuit For Cmos Integrated Circuit Interface, Chee How Lim

Dissertations and Theses

In recent years, strong demand for high-performance electronic products has fueled the need for high-speed and high-integration VLSI circuits. This demand is expected to continue growing in the future, which will lead to development of IC's that are much more compact and operate at higher frequencies. As a result, preserving signal integrity for proper IC communications becomes an increasingly difficult challenge.

In this thesis, an understanding of IC noise in relation to IC packaging is sought. An IC package is modeled with sophisticated 3-D simulators to extract its corresponding parasitics. These parasitics, expressed in terms of resistance, inductance, and capacitance …