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Numerical Solutions Of Boundary Inverse Problems For Some Elliptic Partial Differential Equations, Suxing Zeng

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this dissertation, we study boundary inverse problems for some elliptic partial differential equations. These are problems arising from quantitative analysis of various non-destructive testing techniques in applications. In such a problem, we are interested in using boundary measurements of the solution to recover either an unknown coefficient function in the boundary condition, or a portion of the boundary, or an unknown interior interface. We first introduce formulations of the boundary value problems into integral equations, then design numerical algorithms for solving each of these inverse problems. Numerical implementation and examples are presented to illustrate the feasibility and effectiveness of …

The Effect Of Different Road Load Implementation Strategies On Fuel Economy Of Usps Step Vans, Seiar Ahmad Zia

Graduate Theses, Dissertations, and Problem Reports (ETD)

West Virginia University (WVU) is continuously improving and updating their testing quality, procedures and goals. As tests are conducted on the Transportable Heavy Duty Vehicle Emissions Testing Laboratory (THDVETL), real world implementation is crucial in order to compare and contrast vehicles within fleets, use of exhaust aftertreatment devices and hybridized vehicles. WVU implements road loads on the chassis dynamometer using a method described in 40 CFR §86.1229-85. The proposed method requires three variables from the vehicle: maximum height, maximum width and vehicle weight. The issue with this method arises due to the fact that it does not cover a wide …

Commons, Roger A. Lohmann

Faculty & Staff Scholarship

The commons is a theoretical formalism that is useful in understanding many diverse problems of civil society. A common (or commons) is an economic, political, social, and legal institution that enables joint, shared, mutual or collective natural or social action by agents using a “pool” of shared or jointly held or mutually controlled resources. A substantial body of work exists detailing natural common resource pools acted upon by physical or biological agents. Another large body of work on humanly-directed natural resource pools study the human-natural environment interface, interspecies conflict and population density. Studies of social commons have also looked at …

Estimating The System Costs Of Wind Power Forecast Uncertainty, Judith Cardell, C. Lindsay Anderson, Chin Yen Tee

Engineering: Faculty Publications

Uncertainty in forecasts of wind power generation raises concerns of integrating wind power into power system operations and electricity markets at acceptable costs. The analysis presented in this paper uses an optimal power flow (OPF) model in a Monte Carlo Simulation (MCS) framework to estimate the additional cost of power system operation with uncertain output from a wind farm. A base case dispatch is established along with alternate dispatches based upon a probability distribution of real time wind power generation. The cost of the uncertainty in wind power forecasts is then quantified in terms of the difference in production cost …

Nlo Evolution Of Color Dipoles In N=4sym, Ian Balitsky, Giovanni A. Chrilli

Physics Faculty Publications

High-energy behavior of amplitudes in a gauge theory can be reformulated in terms of the evolution of Wilson-line operators. In the leading logarithmic approximation it is given by the conformally invariant BK equation for the evolution of color dipoles. In QCD, the next-to-leading order BK equation has both conformal and non-conformal parts, the latter providing the running of the coupling constant. To separate the conformally invariant effects from the running-coupling effects, we calculate the NLO evolution of the color dipoles in the conformal N = 4 SYM theory. We define the "composite dipole operators" with the rapidity cutoff preserving conformal …

Virtual Compton Scattering And Neutral Pion Electroproduction In The Resonance Region Up To The Deep Inelastic Region At Backward Angles, G. Laveissiere, N. Degrande, S. Jaminion, C. Jutier, L. Todor, G. E. Dodge, C. E. Hyde, K. Mccormick, P. E. Ulmer, L. B. Weinstein, Jefferson Lab Hall A Collaboration

Physics Faculty Publications

We have made the first measurements of the virtual Compton scattering (VCS) process via the H(e, e′p)γ exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the W-dependence at fixed Q²=1 GeV² and for the Q² dependence at fixed W near 1.5 GeV. The VCS data show resonant structures in the first and second resonance regions. The observed Q² dependence is smooth. The measured ratio of H(e, e′p)γ to H(e, e′p)π⁰ cross sections emphasizes the different sensitivity of these two reactions to the various nucleon resonances. Finally, when compared …

Measurement Of Direct Fₒ(980) Photoproduction On The Proton, K. P. Adhikari, H. Bagdasaryan, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, N. Kalantarians, A. Klein, A.V. Klimenko, S. E. Kuhn, J. Lanchiet, M. R. Niroula, J. Zhang

Physics Faculty Publications

We report on the results of the first measurement of exclusive f₀(980) meson photoproduction on protons for E_γ = 3.0–3.8  GeV and −t = 0.4–1.0  GeV² . Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. The resonance was detected via its decay in the π⁺π⁻ channel by performing a partial wave analysis of the reaction γp→pπ⁺π⁻ . Clear evidence of the f₀(980) meson was found in the interference between P and S waves at M _π+π− ∼1  GeV. The S -wave differential …

Conformal Kernel For The Next-To-Leading-Order Bfkl Equation In 𝒩 = 4 Super Yang-Mills Theory, Ian Balitsky, Giovanni A. Chirilli

Physics Faculty Publications

Using the requirement of Möbius invariance of 𝒩 = 4 super Yang-Mills amplitudes in the Regge limit, we restore the explicit form of the conformal next-to-leading-order Balitsky-Fadin-Kuraev-Lipatov (BFKL) kernel out of the eigenvalues known from the forward next-to-leading-order BFKL result.

On Multi-View Learning With Additive Models, Mark Culp, George Michailidis, Kjell Johnson

Faculty & Staff Scholarship

No abstract provided.

Dna Topoisomerases I From Pseudomonas Aeruginosa And Vaccinia Virus And Their Use As Drug Targets, Teesta Jain

LSU Doctoral Dissertations

Pseudomonas aeruginosa encodes a putative topoisomerase with sequence similarity to the type IB topoisomerase enzyme from vaccinia virus. Residues in the active site are conserved, notably Tyr292 which would be predicted to form the transient covalent bond to DNA. The gene encoding the P. aeruginosa topoisomerase I (PAT) was cloned and expressed in E. coli. The enzyme relaxes supercoiled DNA, while a mutant of P. aeruginosa containing a Tyr292 to Phe substitution at the active site was found to be catalytically inert. This is consistent with the role of Tyr in forming the covalent intermediate. Like vaccinia topoisomerase (VT), PAT …

Remediating Impacts Of Global Climate Change-Induced Submergence On Salt Marsh Ecosystem Functions, Camille Lafosse Stagg

LSU Doctoral Dissertations

Impacts of global climate change, such as sea level rise and severe drought, have altered the hydrology of coastal salt marshes resulting in submergence and subsequent degradation of ecosystem function. A potential method of rehabilitating these systems is the addition of sediment-slurries to increase the elevation of the marsh surface, thus ameliorating the effects of excessive inundation. Although this technique is growing in popularity, the successful restoration of ecological function after sediment addition has received little attention. The purpose of this research was to determine if sediment subsidized salt marshes are functionally equivalent to natural marshes and whether salt marshes …

Experimental Design, Synthesis And Application Of Molecular Micelle Modified Polymeric Nanoparticles For Drug Delivery Systems And Free Radical Detection, Gabriela M. Ganea Visser

LSU Doctoral Dissertations

Biodegradable and biocompatible polymeric nanoparticles such as poly (lactide-co-glycolide) (PLGA) nanoparticles have been extensively studied as drug delivery systems for a variety of pharmaceutical agents. Nanoparticle surface properties are primarily determined by the emulsifiers used in the synthesis process, which have a significant impact on nanoparticle physico-chemical and biological properties. Anionic amino acid – based molecular micelles were used in the emulsification process to prepare monodisperse, small (below 100 nm) PLGA nanoparticles with a well defined spherical shape. Such molecular micelle – modified nanoparticles were used as drug carriers for delivery of antioxidants. Thymoquinone is a natural antioxidant, and an …

Iron Mediated Pecipitation Of Phenol: Protein Aggregates From Sugar Cane Juice, Lee R. Madsen Ii

LSU Doctoral Dissertations

The Louisiana cane sugar industry is moving toward a vertically integrated arrangement where raw sugar producers will have an interest in refining. In the sugar refining process, raw sugar is affined to remove ~50 % of the color. The new refinery that will be built in Louisiana, however, will not include affining stations. To reduce costs of refining, either affining stations will need to be installed at each mill or new technologies that provide equivalent color reduction (~50% or ~750 IU) need to be implemented. As part of this dissertation a new technology for color reduction at raw sugar mills …

An Examination Of Louisiana Educational School Improvement Legislation, Policy Decisions, Initiatives, And Fiscal Expenditure From 1997 To 2005, Belinda Marie Cambre

LSU Doctoral Dissertations

This study sought to identify major school improvement reform programs and initiatives in Louisiana during the period of 1997 to 2005. The criteria used to identify each program included: state funding that averaged at least $2 million per year in state funds; programs that affected teachers and students for school improvement purposes; and, programs that remained in place for at least two school years. The study ultimately yielded nine initiatives that met each of the above listed criteria. Some, but not all, were the result of the School and District Accountability Commission, which was established by Act 478, the 1997 …

Some Results On Cubic Graphs, Evan Morgan

LSU Doctoral Dissertations

Pursuing a question of Oxley, we investigate whether the edge set of a graph admits a bipartition so that the contraction of either partite set produces a series-parallel graph. While Oxley's question in general remains unanswered, our investigations led to two graph operations (Chapters 2 and 4) which are of independent interest. We present some partial results toward Oxley's question in Chapter 3. The central results of the dissertation involve an operation on cubic graphs called the switch; in the literature, a similar operation is known as the edge slide. In Chapter 2, the author proves that we can transform, …

All My Pretty Ones By Stephen Paulus; A Song Cycle For Soprano And Piano On A Text By Michael Dennis Browne, Emily Grundstad Hall

LSU Doctoral Dissertations

Stephen Paulus (b. 1949) is emerging as one of America’s accomplished composers for the voice. He is skilled in writing sensitively for the demands of the solo voice and is becoming known as an important contributor to the genre with approximately 50 art songs, 12 song cycles as well as 10 operas and 250 choral pieces. This paper will discuss the song cycle, All My Pretty Ones, for soprano and piano, which was published in 1984 with a text by Michael Dennis Browne. The cycle was Paulus and Browne’s first collaboration and since its conception the two have continued to …

A Discrete Model Of Guided Modes And Anomalous Scattering In Periodic Structures, Natalia Grigoryevna Ptitsyna

LSU Doctoral Dissertations

We study a discrete prototype of anomalous scattering associated with the interaction of guided modes of a periodic scatterer and plane waves incident upon the scatterer. The transmission anomalies arise because of the non-robustness of a guided mode, a mode that exists only at a specific frequency and wave number pair. The simplicity of the discrete prototype allows one to make certain explicit calculations and proofs, and to examine details of important resonant phenomena of the open wave guides. The main results are (1) a formula for transmission anomalies near a non-robust guided mode with rigorous error estimates that extends …

Investigating Conceptual Teaching Strategies In A Computer Based Mathematics Curriculum: The Case Of R2r, Haitham Sleiman Solh

LSU Doctoral Dissertations

This study investigated the various teaching strategies implemented by the teachers in a computer-based Mathematics course delivery model created by the LSU Math Department and applied in Louisiana High Schools. This model was referred to as R2R (Roadmap to Redesign). It was a course design that includes whole class instruction time (about 25% of class time) in addition to time spent with teacher assistance utilizing computer software (MathXL) to practice exercises, submit homework assignments, and take quizzes and tests.The study aimed to determine the proportion of teachers using the R2R model that opt to support a conceptual agenda in their …

The Indigenous Culture Of School Mathematics In China And The United States: A Comparative Study Of Teachers' Understanding Of Constructivism, Lingqi Meng

LSU Doctoral Dissertations

This study aimed to explore how the indigenous (national) culture of teaching and learning mediates teachers’ understandings of constructivism in China and the U.S. Thirty middle school math teachers who are self-identified with the mathematics teaching reform movement in each country participated in this study (NCTM 2000 Math Standards in the United States or the MOE 2001 Math Standards in China). Both theoretical and empirical methods were adopted for this research. Theoretical analysis led to a new cultural model that helped select appropriate cultural elements for this study. Based on emergence theory, the new model perceives Confucianism and Taoism as …

Storm Surge Dynamics Over Wide Continental Shelves: Numerical Experiments Using The Finite-Volume Coastal Ocean Model, Joao Lima Rego

LSU Doctoral Dissertations

Storm surge is an abnormal rise of the sea surface caused by atmospheric forcing, including the wind stress and atmospheric pressure associated with extra-tropical and tropical cyclones. Hurricanes and typhoons have a great impact on coastal regions, and can cause severe loss of lives and great damages. A systematic investigation of storm surge impact to the coasts of Louisiana and Texas, where the continental shelf reaches up to 200 km in width, is conducted here using the hydrodynamics Finite-Volume Coastal Ocean Model, FVCOM (Chen et al., 2003). The model is applied to the northern Gulf of Mexico to simulate the …

Stability Of Articulated Revetments Against Wave Attack On Shallow Soft Soil Slopes, Edmond Joseph Russo

LSU Doctoral Dissertations

Continuously-connected, articulated revetment systems have potential to decrease the weight of armor cover in resisting wave attack, compared to traditional designs. Modes of instability for sloping revetments include uplift, sliding, and toe roll-up. Design methods are summarized by McDonnell (1998), Pilarczyk (1998), and Herbich (1999). Russo (2003) conducted a field prototype scale investigation on performance of Articulated Concrete Mattresses (ACMs) in coastal Louisiana, which demonstrated this structure’s ability to resist a range of wave loading conditions, and inspired scoping of further research to quantify structure performance beyond known limits. Present research expanded earlier works by examining fundamental physical processes of …

Progressive Water-Oil Transition Zone Due To Transverse Mixing Near Wells, Shengkai Duan

LSU Doctoral Dissertations

This study derives from observations made in petroleum research and practices of chemical industry that efficient mixing takes place in segregated immiscible fluid flow in granular packs and static mixers. A hypothesis was formulated that transverse mixing (TM) across oil-water interface may occur in segregated inflow to wells resulting in progressive transition zone, more water production, and reduced oil productivity. “Mixing” is broadly interpreted here to address the entire range of stirring, splitting, dispersion and diffusion processes between two fluids.

Initial study showed that a commercial reservoir simulator would not model any transition zone in segregated oil-water flow at high …

The Role Of Climate Variability And Riverine Pulsing In The Community Dynamics Of Estuarine Nekton In Breton Sound, Louisiana, Bryan Patrick Piazza

LSU Doctoral Dissertations

Climate controls biotic community composition at multiple spatiotemporal scales through variability in environmental control mechanisms (assembly filters). This research investigated the role of climate variability in the community dynamics of estuarine nekton in Breton Sound estuary, Louisiana, and, specifically the effects of El Niño Southern Oscillation (ENSO), freshwater discharge, and a tropical cyclone. A teleconnection was found between ENSO and juvenile brown shrimp (Farfantepenaeus aztecus) abundance in Breton Sound from 1988 – 2007. ENSO affected winter weather conditions (air pressure, temperature and precipitation), and spring brown shrimp abundance in Breton Sound. Juvenile brown shrimp abundance lagged ENSO by …

Convolution Semigroups, Kevin W. Zito

LSU Doctoral Dissertations

In this dissertation we investigate, compute, and approximate convolution powers of functions (often probability densities) with compact support in the positive real numbers. Extending results of Ursula Westphal from 1974 concerning the characteristic function on the interval $[0,1]$, it is shown that positive, decreasing step functions with compact support can be embedded in a convolution semigroup in $L^1(0,infty)$ and that any decreasing, positive function $pin L^1(0,infty)$ can be embedded in a convolution semigroup of distributions. As an application to the study of evolution equations, we consider an evolutionary system that is described by a bounded, strongly continuous semigroup ${T(t)}_{tgeq0}$ in …

The Dape-Encoded N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase From Haemophilus Influenzae Contains Two Active-Site Histidine Residues, Danuta Gillner, David L. Bienvenue, Boguslaw P. Nocek, Andzrej Joachimiak, Vincentos Zachary, Brian Bennett, Richard C. Holz

Physics Faculty Research and Publications

The catalytic and structural properties of the H67A and H349A dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) from Haemophilus influenzae were investigated. On the basis of sequence alignment with the carboxypeptidase from Pseudomonas sp. strain RS-16, both H67 and H349 were predicted to be Zn(II) ligands. The H67A DapE enzyme exhibited a decreased catalytic efficiency (180-fold) compared with wild-type (WT) DapE towards N-succinyldiaminopimelic acid. No catalytic activity was observed for H349A under the experimental conditions used. The electronic paramagnetic resonance (EPR) and electronic absorption data indicate that the Co(II) ion bound to H349A-DapE is analogous to that of WT …

Mutation Of H63 And Its Catalytic Affect On The Methionine Aminopeptidase From Escherichia Coli, Sanghamitra Mitra, Brian Bennett, Richard C. Holz

Physics Faculty Research and Publications

In order to gain insight into the mechanistic role of a flexible exterior loop near the active site, made up of Y62, H63, G64, and Y65, that has been proposed to play an important role in substrate binding and recognition in the methionyl aminopeptidase from Escherichia coli (EcMetAP-I), the H63A enzyme was prepared. Mutation of H63 to alanine does not affect the ability of the enzyme to bind divalent metal ions. The specific activity of H63A EcMetAP-I was determined using four different substrates of varying lengths, namely, l-Met-p-NA, MAS, MGMM and MSSHRWDW. For the smallest/shortest …

Antivortex Dynamics In Magnetic Nanostripes, Andrew Kunz, Eric C. Breitbach, Andy J. Smith

Physics Faculty Research and Publications

In a thin magnetic nanostripe, an antivortex nucleates inside a moving domain wall when driven by an in-plane magnetic field greater than the so-called Walker field. The nucleated antivortex must cross the width of the nanostripe before the domain wall can propagate again, leading to low average domain wall speeds. A large out-of-plane magnetic field, applied perpendicularly to the plane of the nanostripe, inhibits the nucleation of the antivortex leading to fast domain wall speeds for all in-plane driving fields. We present micromagnetic simulation results relating the antivortex dynamics to the strength of the out-of-plane field. An asymmetry in the …

Water Evaporation From Atmospheric Aerosols, Patrick Louden, Christopher Lawrence

Student Summer Scholars Manuscripts

With the recent discovery of the ubiquity of organic material in tropospheric aerosols, it has been postulated that the rates of water evaporation and condensation into the aerosols could be affected by thin surfactant films, which could ultimately affect cloud formation. Nathanson et al. have begun to study the effect of water evaporation from sulfuric acid solutions through the short-chain surfactant, butanol. They have found that a nearly full monolayer of butanol fails to reduce water evaporation from the acid. This unexpected result raises many questions about the mechanism of water evaporation. We used molecular modeling to help answer some …

Rook Polynomials In Higher Dimensions, Nicholas Krzywonos, Feryal Alayont

Student Summer Scholars Manuscripts

A rook polynomial counts the number of placements of non-attacking rooks on a board. In this paper we describe generalizations of the definition and properties of rook polynomials to "boards" in three and higher dimensions. We also defefine generalizations of special two dimensional boards to three dimensions, including the triangle board and the board representing the probleme des rencontres. The number of rook placements on these three dimensional families of rook boards are shown to be related to famous number sequences, such as central factorial numbers, the number of Latin rectangles and the Genocchi numbers.

Modeling Problem Solving: Creating And Evaluating, Kaitlin M. Downey, Nathan Barrows

Student Summer Scholars Manuscripts

The purpose of this project was to create novice-level screencasts and to investigate students’ perceptions and usage of them. A survey of 61 general chemistry students revealed polarity, Lewis structures, molecular geometry, and bond polarity to be topics of greatest concern. Over 25 screencasts were created using Camtasia Studio software and a Dell TabletPC. A blog (http://mi-chemed.net) was created to host the tutorials and monitor student usage. After students registered and logged in to the blog, their viewing patterns were recorded. They were encouraged to comment on the content and technical features of the videos (e.g. animations). Online comments and …