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2002

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Optimal Channel Equalization For Filterbank Transceivers In Presence Of White Noise, Ehab Farouk Badran Jan 2002

Optimal Channel Equalization For Filterbank Transceivers In Presence Of White Noise, Ehab Farouk Badran

LSU Doctoral Dissertations

Filterbank transceivers are widely employed in data communication networks to cope with inter-symbol-interference (ISI) through the use of redundancies. This dissertation studies the design of the optimal channel equalizer for both time-invariant and time-varying channels, and wide-sense stationary (WSS) and possible non-stationary white noise processes. Channel equalization is investigated via the filterbank transceivers approach. All perfect reconstruction (PR) or zero-forcing (ZF) receiver filterbanks are parameterized in an affine form, which eliminate completely the ISI. The optimal channel equalizer is designed through minimization of the mean-squared-error (MSE) between the detected signals and the transmitted signals. Our main results show that the …


Impact Of Subject Related Factors And Position Of Flight Control Stick On Acquisition Of Simulated Flying Skills Using A Flight Simulator, Bo-Keun Cho Jan 2002

Impact Of Subject Related Factors And Position Of Flight Control Stick On Acquisition Of Simulated Flying Skills Using A Flight Simulator, Bo-Keun Cho

LSU Doctoral Dissertations

Increasing demand on aviation industry calls for more pilots. Thus, pilot training systems and pilot-candidate screening systems are essential for civil and military flying training institutes. Before actual flight training, it is not easy to determine whether a flight trainee will be successful in the training. Due to the high cost of actual flight training, it would be better if there were low cost methods for screening and training candidates prior to the actual flight training. This study intended to determine if subject related factors and flight control stick position have an impact on acquisition of simulated flying skills using …


Louisiana Mass Media Perceptions Of The Lsu Agcenter's Communications Effort, Robert James Soileau Jan 2002

Louisiana Mass Media Perceptions Of The Lsu Agcenter's Communications Effort, Robert James Soileau

LSU Master's Theses

LSU AgCenter Communications sends news stories and materials to all three major mass media for news - newspaper, radio and television - in the state of Louisiana. These news releases are designed to educate and inform the general public about LSU AgCenter programs and research through the Louisiana Cooperative Extension Service and the Louisiana Agricultural Experiment Station. LSU AgCenter Communications wanted to know the effectiveness of its news effort in terms of usage by the media, and what was the media’s perception of the LSU AgCenter and the topics covered by communications. Three researcher-designed surveys were developed, one for each …


Branch, Crown, Tree And Stand Water Flux In An 180-Year-Old Loblolly Pine Plantation After Thinning, Fertilization, And Throughfall Exclusion Treatments, Shufang Yu Jan 2002

Branch, Crown, Tree And Stand Water Flux In An 180-Year-Old Loblolly Pine Plantation After Thinning, Fertilization, And Throughfall Exclusion Treatments, Shufang Yu

LSU Doctoral Dissertations

Branch and tree sap flux density (SFD) was measured to evaluate the effects of thinning, fertilization, and throughfall exclusion treatments on water use by loblolly pine (Pinus taeda L.) trees. Variations in SFD at different radial xylem depths were also examined to improve estimates of tree water use from sap flux density measured in the outer sapwood. This study was conducted in an 18-year-old loblolly pine plantation in central Louisiana in 1999. The results revealed that SFD was higher in the outer xylem than in the inner xylem and large trees had higher SFD than small trees. Thinning increased daily …


The Combined Effects Of Salinity And Sulfide On The Growth And Physiology Of The Freshwater Marsh Plant Pancium Hemitomon J.A. Schultes, James Wesley Pahl Jan 2002

The Combined Effects Of Salinity And Sulfide On The Growth And Physiology Of The Freshwater Marsh Plant Pancium Hemitomon J.A. Schultes, James Wesley Pahl

LSU Doctoral Dissertations

Vegetative response to saltwater intrusion into coastal freshwater wetlands is governed by the combined effects of increased salinity and porewater sulfide concentrations. I conducted a series of experiments to address the primary hypothesis that growth of Panicum hemitomon is adversely affected by an interaction between salinity and sulfide stresses associated with saltwater intrusion, and the mechanisms for decreased growth are alterations in the metabolic and morphological adaptations needed for a plant to survive in a flooded environment. I exposed marsh sods to a factorial treatment arrangement of three salinities (0, 2, and 4 ppt) and three porewater sulfide concentrations (0, …


A Factorization Approach For Solving The Hamilton-Jacobi Equations In Nonlinear Optimal Control, Mohammad Dikko Aliyu Jan 2002

A Factorization Approach For Solving The Hamilton-Jacobi Equations In Nonlinear Optimal Control, Mohammad Dikko Aliyu

LSU Doctoral Dissertations

The Hamilton-Jacobi equation (HJE) arose early in the last century in the study of the calculus of variation, classical mechanics and Hamiltonian systems. Recently, there has been a renewed interest in HJEs arising in various analysis and synthesis problems in systems theory. The HJE despite providing a necessary and sufficient condition for an optimal control, is very difficult to solve for general nonlinear systems, and therefore its application remained limited to linear systems. Yet, the HJE has been studied extensively in the literature from diverse areas of science and engineering, varying from mathematical physics, to mechanics, control theory, and to …


Numerical Reservoir Characterization Using Dimensionless Scale Numbers With Application In Upscaling, Djuro Novakovic Jan 2002

Numerical Reservoir Characterization Using Dimensionless Scale Numbers With Application In Upscaling, Djuro Novakovic

LSU Doctoral Dissertations

Dimensionless space provides a tool for analyzing the behavior of complex systems described by mathematical relationships. The limited application of dimensionless variables in numerical reservoir simulation and experimental design motivated the development of a complete set of dimensionless scaling groups. Inspectional analysis yielded 8 dimensionless groups completely describing the flow system. Further analysis of fluid interaction reduced the number of dimensionless groups to 7. The newly developed dimensionless equations and groups were used for analytical and numerical reservoir characterization, quantifying the behavior of differential and difference equations employed in fluid flow in three-dimensional porous media. The behavior of the dimensionless …


Northern Pintail Nest Site Selection, Nest Success, Renesting Ecology And Survival In The Intensively Farmed Prairies Of Southern Saskatchewan: An Evaluation Of The Ecological Trap Hypothesis, Kenneth Daniel Richkus Jan 2002

Northern Pintail Nest Site Selection, Nest Success, Renesting Ecology And Survival In The Intensively Farmed Prairies Of Southern Saskatchewan: An Evaluation Of The Ecological Trap Hypothesis, Kenneth Daniel Richkus

LSU Doctoral Dissertations

Unlike most prairie nesting ducks (Anas spp.), the North American population of northern pintails (A. acuta, hereafter pintails) has failed to respond as expected to improved wetland conditions on the U.S. and Canadian prairies during the mid to late 1990s. My primary objectives were to test the “ecological trap hypothesis” on a landscape level by examining pintail nest site selection and nest success in a highly agricultural environment in southern Saskatchewan. I also used radiotelemetry to estimate renesting and breeding season survival rates of female pintails; two parameters that are important in productivity and life cycle models. Most (51%) pintail …


Reconceiving Curriculum: An Historical Approach, Stephen Shepard Triche Jan 2002

Reconceiving Curriculum: An Historical Approach, Stephen Shepard Triche

LSU Doctoral Dissertations

This dissertation reconceives curriculum through an historical approach that employs Ludwig Wittgenstein’s later philosophy. Curriculum is more than the knowledge taught in school. Curriculum, as I a theorist conceives it, is concerned with the broader intellectual and ideological ways a society thinks about education. Hence, the current school curriculum’s focus on specific learning outcomes offers a limited view of the knowledge fashioned by a society, thereby offering an intellectual and social history that is highly selective. Wittgenstein’s concept of “language-games” offers curricularists a way to re-include some of these stories. The concept of curriculum emerges at the end of the …


The Importance Of Zooplankton In The Diets Of Blue Runner (Caranx Crysos) Near Offshore Petroleum Platforms In The Northern Gulf Of Mexico, Sean Francis Keenan Jan 2002

The Importance Of Zooplankton In The Diets Of Blue Runner (Caranx Crysos) Near Offshore Petroleum Platforms In The Northern Gulf Of Mexico, Sean Francis Keenan

LSU Master's Theses

Blue runner (Caranx crysos), common around offshore petroleum platforms in the Gulf of Mexico, were found to forage extensively on meso- and macro-zooplankton during the summer months. Larval decapods and stomatopods, hyperiid amphipods, pteropods, and larval and juvenile fishes were common components of their diet. Feeding periodicity results suggest that blue runner around platforms were capable of feeding throughout the night at the same intensity as the day. Size selectivity indicated that larger prey, such as fish were consumed during the night and smaller decapod crustaceans were consumed during the day. Blue runner collected from open waters away from platforms …


Explicit Multiplicative Relations Between Gauss Sums, Brian J. Murray Jan 2002

Explicit Multiplicative Relations Between Gauss Sums, Brian J. Murray

LSU Doctoral Dissertations

H.Hasse conjectured that all multiplicative relations between Gauss sums essentially follow from the Davenport-Hasse product formula and the norm relation for Gauss sums. While this is known to be false, very few counterexamples, now known as sign ambiguities, have been given. Here, we provide an explicit product formula giving an infinite class of new sign ambiguities and resolve the ambiguous sign in terms of the order of the ideal class of quadratic primes.


Electronic And Structural Properties Of Rare Gas Cation Clusters, Jose Alejandro Gascon Jan 2002

Electronic And Structural Properties Of Rare Gas Cation Clusters, Jose Alejandro Gascon

LSU Doctoral Dissertations

We study structure and ground and excited state properties of rare gas cation clusters, Rg+N, for N=3-60. The main goal is to understand how the positive charge is delocalized over the cluster and the relationship between cluster geometry and delocalization. He+N, Ar+N, and Xe+N are selected as representatives of the rare gas elements. We perform Monte Carlo simulations to obtain finite temperature properties of the energy spectrum. The Hamiltonian of the system is based on a semi-empirical model whose parameters are obtained through the fitting of experimental and calculated …


Sedimentation Rates And Metal Retention In An Urban Louisiana Swamp, Renee Lynn Sanders Jan 2002

Sedimentation Rates And Metal Retention In An Urban Louisiana Swamp, Renee Lynn Sanders

LSU Master's Theses

Naturally vegetated areas converted to urban uses increases impervious surfaces in a watershed with corresponding increases in nutrient, sediment, and metal loadings to downstream ecosystems. Wetlands mitigate detrimental impacts by transforming or retaining pollutants. Current and historic sedimentation and metal retention rates were measured in an urban, depressional wetland in Baton Rouge, Louisiana to evaluate landscape position and watershed development on these processes. Sedimentation disks, feldspar marker horizons, and Cs137 analyses were used in three distinct landscape positions. Inflow channels had the highest elevation and water velocity while the interior was located in the lowest elevations with the longest hydroperiod. …


Thermal Rheological Analysis Of Cure Process Of Epoxy Prepreg, Liangfeng Sun Jan 2002

Thermal Rheological Analysis Of Cure Process Of Epoxy Prepreg, Liangfeng Sun

LSU Doctoral Dissertations

The cure process of epoxy prepreg used as composite pipe joints was studied by means of differential scanning calorimetry (DSC), Bohlin Rheometer and other techniques. Isothermal DSC measurements were conducted between 110 and 220 oC, at 10 oC intervals. The results show that the complete cure reaction could be achieved at oC. The isothermal cure process was simulated with the four-parameter autocatalytic model. Except in the late stage of cure reaction, the model agrees well with the experimental data, especially at high temperatures. To account for the effect of diffusion on the cure rate, a diffusion factor was introduced into …


Hydrodynamics And Freshwater Diversion Within Barataria Basin, Dongho Park Jan 2002

Hydrodynamics And Freshwater Diversion Within Barataria Basin, Dongho Park

LSU Doctoral Dissertations

In order to understand the physical processes in the Barataria estuary, a previously developed two-dimensional, depth-integrated hydrodynamic model is applied to simulate estuarine processes. The equations for conservation of mass and momentum predict specific physical processes when forced by tidal and salinity variations at the open boundaries, wind forcing patterns, precipitation and evaporation over the model domain, and freshwater runoff as point sources. This study is focused on examining the impact of freshwater dispersion from the freshwater sources. Thus, a hydrologic model was developed to estimate runoff. Furthermore grid size was reduced, a new advective code added, and baroclinic effects …


Essays On The Bayesian Inequality Restricted Estimation, Asli K. Ogunc Jan 2002

Essays On The Bayesian Inequality Restricted Estimation, Asli K. Ogunc

LSU Doctoral Dissertations

Bayesian estimation has gained ground after Markov Chain Monte Carlo process made it possible to sample from exact posterior distributions. This research aims at contributing to the ongoing debate about the relative virtues of the Frequentist and Bayesian theories by concentrating on the qualitative dependent variable models. Two Markov Chain Monte Carlo (MCMC) methods have been used throughout this dissertation to facilitate Bayesian estimation, namely Gibbs (1984) sampling and the Metropolis (1953, 1970) Algorithm. In this research, several Monte Carlo experiments have been carried out to better understand the finite sample properties of Bayesian estimator and its relative performance to …


Essays On International Trade And Bayesian Forecasting, Dennis S. Edwards Jan 2002

Essays On International Trade And Bayesian Forecasting, Dennis S. Edwards

LSU Doctoral Dissertations

Economic theory is subject to continual analysis. While theories themselves are sometimes widely accepted, nuances of theory are persistently scrutinized. Researchers have not isolated this debate from a simply theoretic standpoint. Empirical methods in microeconomics also provide a forum for disagreement. This dissertation studies two topics of microeconomic theory that are constantly in debate: integration and cost function estimation. From the standpoint of theoretical integration models in international trade theory, the concept of foreign direct investment is studied in both a horizontal and vertical setting. With respect to horizontal integration, this dissertation modifies the Brander-Krugman reciprocal dumping model to evaluate …


A State-Of-The-Practice Review Of Hurricane Evacuation Plans And Policies, Elba Alicia Urbina Jan 2002

A State-Of-The-Practice Review Of Hurricane Evacuation Plans And Policies, Elba Alicia Urbina

LSU Master's Theses

The events of recent hurricane seasons have made evacuation one of the leading emergency management issues. In 1998 and 1999, Hurricanes Georges and Floyd precipitated the two largest evacuations in U.S. history and perhaps, its two largest traffic jams. In response to the problems experienced during these events, many State Department’s of Transportation (DOT) have begun to take a more active role in the planning, management, and operation of hurricane evacuations. Since the involvement of transportation professionals in the evacuation field has been a fairly recent development; many of the newest practices and policies have only been used once, if …


Net.Sense, John Mikucki Jan 2002

Net.Sense, John Mikucki

Theses

Net.sense will server as a proof-of-concept of a new type of network management system, using biological models and statistical principles to address scalability, predictability, and reliability issues associated with managing the highly complex computer systems that we as a society have come to depend on.


On The Evolution Of Simple Material Structures, Marek Elźanowski, Ernst Binz Jan 2002

On The Evolution Of Simple Material Structures, Marek Elźanowski, Ernst Binz

Mathematics and Statistics Faculty Publications and Presentations

The evolution of a distribution of material inhomogeneities is investigated by analyzing the evolution of the corresponding material connections. Some general geometric relations governing such evolutions are derived. These relations are then analyzed by looking at the restrictions imposed by the material symmetry group.


Conformal Laplacian And Conical Singularities, Boris Botvinnik, Serge Preston Jan 2002

Conformal Laplacian And Conical Singularities, Boris Botvinnik, Serge Preston

Mathematics and Statistics Faculty Publications and Presentations

We study a behavior of the conformal Laplacian operator $\L_g$ on a manifold with \emph{tame conical singularities}: when each singularity is given as a cone over a product of the standard spheres. We study the spectral properties of the operator $\L_g$ on such manifolds. We describe the asymptotic of a general solution of the equation $\L_g u = Q u^{\alpha}$ with 1≤α≤n+2 near each singular point. In particular, we derive the asymptotic of the Yamabe metric near such singularity.


The Lawyer-Negotiator As Mood Scientist: What We Know And Don't Know About How Mood Relates To Successful Negotiation, Clark Freshman, Adele Hayes, Greg Feldman Jan 2002

The Lawyer-Negotiator As Mood Scientist: What We Know And Don't Know About How Mood Relates To Successful Negotiation, Clark Freshman, Adele Hayes, Greg Feldman

Faculty Scholarship

No abstract provided.


Teaching Mathematical Problem Solving In The Context Of Oregon's Educational Reform, Nicole R. Rigelman Jan 2002

Teaching Mathematical Problem Solving In The Context Of Oregon's Educational Reform, Nicole R. Rigelman

Dissertations and Theses

Implementation of Oregon’s Educational Reform Act (HB 3565 and HB 2991) provides the context for this inquiry as its emphasis on problem solving has impacted mathematics teaching and learning throughout the state. Even though all Oregon teachers are responding to the same policy, their goals in teaching problem solving vary. These goals and these practices are influenced by the way teachers view the role of problem solving in the curriculum. Further, their practice is influenced by their knowledge and beliefs about mathematics content, teaching, learning, and the reform policy. The questions addressed in this study are: (1) What do exemplary …


Tidal Dynamics In The Bab El Mandab Strait, Ewa Jarosz Jan 2002

Tidal Dynamics In The Bab El Mandab Strait, Ewa Jarosz

LSU Doctoral Dissertations

The Bab el Mandab Strait is where the transition occurs between two noticeably different tidal regimes: the Gulf of Aden, where tidal fluctuations are mixed and have a range in excess of 2 m, and the Red Sea, where the tides are principally semidiurnal and their range is less than 1 m. Within the Strait, observations collected between May of 1995 and July of 1997 indicate that tidal currents are a mixed type and dominant constituents are the K1 and M2. The vertical structure of the tidal currents is complicated, differs between semidiurnal and diurnal constituents, and …


It Came From Outer Space: The Virus, Cultural Anxiety, And Speculative Fiction, Anne-Marie Thomas Jan 2002

It Came From Outer Space: The Virus, Cultural Anxiety, And Speculative Fiction, Anne-Marie Thomas

LSU Doctoral Dissertations

This study seeks to explore and interrogate the “viral reality” of the 1990s, in which the virus, heavily indebted to representations of AIDS for its metaphorical power, emerged as a prominent agent in science and popular culture. What becomes apparent in both fictional and non-fictional texts of this era, however, is that the designation of “virus” transcends specific and material viral phenomena, making the virus itself a touchstone for modern preoccupations with self and other. As constituted by the human body’s interaction with pathogenic agents, the binary of self and other may be deconstructed by an interrogation of the virus …


Indirect-Drive Noncryogenic Double-Shell Ignition Targets For The National Ignition Facility: Design And Analysis, Peter A. Amendt, J. D. Colvin, R. E. Tipton, D. E. Hinkel, M. J. Edwards, O. L. Landen, John D. Ramshaw, L. J. Suter, W. S. Varnum, R. G. Watt Jan 2002

Indirect-Drive Noncryogenic Double-Shell Ignition Targets For The National Ignition Facility: Design And Analysis, Peter A. Amendt, J. D. Colvin, R. E. Tipton, D. E. Hinkel, M. J. Edwards, O. L. Landen, John D. Ramshaw, L. J. Suter, W. S. Varnum, R. G. Watt

Physics Faculty Publications and Presentations

Analysis and design of indirect-drive National Ignition Facility double-shell targets with hohlraum temperatures of 200 eV and 250 eV are presented. The analysis of these targets includes the assessment of two-dimensional radiation asymmetry and nonlinear mix. Two-dimensional integrated hohlraum simulations indicate that the x-ray illumination can be adjusted to provide adequate symmetry control in hohlraums specially designed to have high laser-coupling efficiency [Suter et al., Phys. Plasmas 7, 2092 (2000)]. These simulations also reveal the need to diagnose and control localized 10?15 keV x-ray emission from the high-Z hohlraum wall because of strong absorption by the high-Z inner shell. Preliminary …


Analytically Continued Hypergeometric Expression Of The Incomplete Beta Function, Jack C. Straton Jan 2002

Analytically Continued Hypergeometric Expression Of The Incomplete Beta Function, Jack C. Straton

Physics Faculty Publications and Presentations

The Incomplete Beta Function is rewritten as a Hypergeometric Function that is the analytic continuation of the conventional form, a generalization of the finite series, which simpifies the Stieltjes transform of powers of a monomial divided by powers of a binomial.


Fluid Dynamics And Energetics In Ideal Gas Mixtures, John D. Ramshaw Jan 2002

Fluid Dynamics And Energetics In Ideal Gas Mixtures, John D. Ramshaw

Physics Faculty Publications and Presentations

The generalization of fluid dynamics from pure to multicomponent fluids (fluid mixtures composed of different components or species) requires the introduction of new concepts, some of which are rather subtle and are less widely appreciated than they deserve to be. The purpose of this paper is to provide a simple didactic introduction to some of these concepts based on a detailed analysis of the equations governing the flow of ideal gas mixtures. The treatment is based entirely on a continuum description and makes no explicit use of the kinetic theory of gases. We include a straightforward and physically transparent derivation …


Algal Blooms Reduce The Uptake Of Toxic Methylmercury In Freshwater Food Webs, Paul C. Pickhardt, Carol L. Folt, Celia Y. Chen, Bjoern Klaue, Joel D. Blum Jan 2002

Algal Blooms Reduce The Uptake Of Toxic Methylmercury In Freshwater Food Webs, Paul C. Pickhardt, Carol L. Folt, Celia Y. Chen, Bjoern Klaue, Joel D. Blum

Dartmouth Scholarship

Mercury accumulation in fish is a global public health concern, because fish are the primary source of toxic methylmercury to humans. Fish from all lakes do not pose the same level of risk to consumers. One of the most intriguing patterns is that potentially dangerous mercury concentrations can be found in fish from clear, oligotrophic lakes whereas fish from greener, eutrophic lakes often carry less mercury. In this study, we experimentally tested the hypothesis that increasing algal biomass reduces mercury accumulation at higher trophic levels through the dilution of mercury in consumed algal cells. Under bloom dilution, as algal biomass …


Querying Geographically Dispersed, Heterogeneous Data Stores: The Pperfxchange Approach, Matthew Edward Colgrove Jan 2002

Querying Geographically Dispersed, Heterogeneous Data Stores: The Pperfxchange Approach, Matthew Edward Colgrove

Dissertations and Theses

This thesis details PPerfXchange’s approach for querying geographically dispersed heterogeneous data stores. While elements of PPerfXchange’s method have been implemented for other application areas, PPerfXchange shows how these elements can be applied to parallel performance analysis. The accomplishments of this thesis are:

  • The design of an architecture for PPerfXchange, giving a uniform method to query heterogeneous data stores;
  • A proof of concept prototype implementation of PPerfXchange including a partial implementation of an XQuery processor and a relational database virtual XML document; and
  • Evaluation of PPerfXchange using example parallel performance analysis data.