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2002

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Efficient Convolvers Using The Polynomial Residue Number System Technique, Surendar Paruchuri Jan 2002

Efficient Convolvers Using The Polynomial Residue Number System Technique, Surendar Paruchuri

LSU Master's Theses

The problem of computing linear convolution is a very important one because with linear convolution we can mechanize digital filtering. The linear convolution of two N-point sequences can be computed by the cyclic convolution of the following 2N-point sequences. The original sequence padded with N zero’s each. The cyclic convolution of two N-point sequences requires multiplications and additions for its computation. A very efficient way of computing cyclic convolution of two sequences is by using the Polynomial Residue Number System (PRNS) technique. Using this technique the cyclic convolution of two N-point sequences can be computed using only N multiplications instead …

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Implementation Of An Integrated Quality Assurance Program For Ct-Tps Process, Junqing Wu Jan 2002

Implementation Of An Integrated Quality Assurance Program For Ct-Tps Process, Junqing Wu

LSU Master's Theses

Systematic constancy and accuracy of a treatment planning system (TPS) are crucial for the entire radiation treatment planning process (TPP). The Quality Assurance (QA) of individual components does not necessarily lead to satisfying performance of the whole process due to the possible errors introduced by the data transfer process between components and other fluctuations. However, most of current QA for TPS is confined to the treatment planning computers. In this study, a time efficient and integrated CT-TPS QA procedure is presented, which starts at the beginning of the TPS input --- Computer Tomograhpy (CT). The whole QA procedure is based …

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Supercritical Carbon Dioxide Extraction Of Lipids From Raw And Bioconverted Rice Bran, Rohit Badal Jan 2002

Supercritical Carbon Dioxide Extraction Of Lipids From Raw And Bioconverted Rice Bran, Rohit Badal

LSU Master's Theses

Rice bran is often discarded despite its nutritional value because the oil in rice bran easily becomes rancid. This has necessitated the search for a method for utilizing the rice bran. The present study involves the application of supercritical fluid extraction (SFE) and bioprocessing (microbial growth on rice bran media) for increasing the value of the rice bran to produce products of high value (nutraceuticals) with superior health benefit. This study was focused on determining the effect of particle size (>48 mesh and 16-48 mesh) and biotreatment on the yield and quality of rice bran oil. SFE technique (40°C, …

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The Effects Of Fall Coldfront Passages On The Nekton Community In A Tidal Creek In Port Fourchon, La, As Monitored By Hydroacoustics, David J. Harmon Jan 2002

The Effects Of Fall Coldfront Passages On The Nekton Community In A Tidal Creek In Port Fourchon, La, As Monitored By Hydroacoustics, David J. Harmon

LSU Master's Theses

Split-beam hydroacoustic sampling with two, 420 KHz, 2x6 degree elliptical transducers was evaluated as a tool to quantify nekton movements in a Louisiana estuary. I measured the effects of atmospheric cold front passages on nekton in a tidal creek in Port Fourchon, LA during the fall of 2000. Six “fronts” were sampled between October 6 and December 18, 2000. Nekton density ranged from 0 to 24.4 fish/m3 with an overall mean of 2.44 fish/m3. Net samples were taken to supplement the acoustic data with species composition data. Species composition changed from October to December. A higher number …

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Exotic Integral Witt Equivalence Of Algebraic Number Fields, Changheon Kang Jan 2002

Exotic Integral Witt Equivalence Of Algebraic Number Fields, Changheon Kang

LSU Doctoral Dissertations

Two algebraic number fields K and L are said to be exotically integrally Witt equivalent if there is a ring isomorphism W(OK) ~ W(OL) between the Witt rings of the number rings OK and OL of K and L, respectively. This dissertation studies exotic integral Witt equivalence for totally complex number fields and gives necessary and sufficient conditions for exotic integral equivalence in two special classes of totally complex number fields.

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Adult-Mediated Reading Instruction For Third Through Fifth Grade Children With Reading Difficulties, Randy Paul Lachney Jan 2002

Adult-Mediated Reading Instruction For Third Through Fifth Grade Children With Reading Difficulties, Randy Paul Lachney

LSU Doctoral Dissertations

This dissertation examined the efficacy of using minimally trained college undergraduates to tutor third- through fifth-grade students with reading difficulties. Tutors receiving four hours of training in scripted reading program based on the principles of Direct Instruction and emphasizing explicit instruction in phonological awareness and decoding. Thirty-six students from two elementary schools in a large southeastern city in the United States were selected and randomly assigned to treatment (tutoring) or contrast (non-tutoring) conditions. Treatment students received an average of fourteen and a half hours of tutoring over a twelve-week period. Data indicated that university students with minimal training successfully implemented …

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Toward A Design Process, Joel Shay Aulie Jan 2002

Toward A Design Process, Joel Shay Aulie

LSU Master's Theses

This project presents an unconventional approach to an innovative design process. The thesis relates the challenges of adapting to the design studio environment. The author describes a personal journey into the design process, resulting from research and study of specific designers who have had high impact on the new creative approach to landscape design. The insight and knowledge gained from this search was instrumental in the evolutional process of design, incorporating a universal technique. The resultant process was then applied to a case study and evaluated for merit. The measure of a designer ultimately becomes the work he produces.

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The Differences In Performance Of A Left Vs. Right Brained Golfer On A Curvilinear Golf Course, Robin Suzanne Jamison Jan 2002

The Differences In Performance Of A Left Vs. Right Brained Golfer On A Curvilinear Golf Course, Robin Suzanne Jamison

LSU Master's Theses

Our everyday movement is reflected by those individuals who design the world in which we live. Ninety percent of the people who shape our everyday lives are right handed. Individuals perceive life differently, especially left and right handed individuals. One reason left and right-handed individuals interpret differently is due to the brains’ two hemispheres processing information separately. Can this difference in interpretation result in varying abilities of performance? Research has proven that those individuals who are right hemisphere dominant process and comprehend shapes better than left hemisphere dominant individuals. Golf is an activity that is exhibits the constant changing of …

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Visco-Elastic Creep In The Lumbar Spine Associated With Static Flexion: A Feline Model, Guntulu Selen Hatipkarasulu Jan 2002

Visco-Elastic Creep In The Lumbar Spine Associated With Static Flexion: A Feline Model, Guntulu Selen Hatipkarasulu

LSU Master's Theses

Musculoskeletal disorders (MSDs) have become a major health concern with the industrial revolution and technological advances. The National Institute for Occupational Safety and Health (NIOSH) recently estimated the cost of MSDs at $13 to $20 billion annually. Back, spine, and spinal cord disorders add up to 60% of the total MSD injuries. Based on pervious studies, it is known that lumbar ligaments play a limited or little role in stabilizing the spine; where as the musculature around the spine is the major stabilizing structure. However, repetitive or prolonged static displacement or load induces creep in passive tissues of the spine …

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Group Automorphisms And The Decomposition Of Plancherel Measures, David Slay Jan 2002

Group Automorphisms And The Decomposition Of Plancherel Measures, David Slay

LSU Doctoral Dissertations

In this paper, a natural action of the automorphisms of a group on the space of irreducible unitary representations is used to decompose the Plancherel measure on the dual space as an integral of measures on homogeneous spaces. Explicit decompositions are obtained for the cases of free 2 and 3-step nilpotent Lie groups. These results are obtained using direct integral decompositions, induced representations, the Mackey Machine, and measure theory on homogeneous spaces.

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Fecal Coliform Decay And Regrowth Kinetics In An Anaerobic Dairy Wastewater Environment, Shufang Liu Jan 2002

Fecal Coliform Decay And Regrowth Kinetics In An Anaerobic Dairy Wastewater Environment, Shufang Liu

LSU Master's Theses

The kinetics of fecal coliforms (FC) decay and regrowth were analyzed under laboratory conditions using filtered dairy wastewater under anaerobic conditions. The mean specific growth rates during the regrowth phase, µr , in the batch study were 1.79, 1.46, and 1.27d-1 for initial organic carbon concentrations of 478, 235 and 127 mg/L COD, respectively. The substrate concentrations had a significant impact on the FC regrowth. A maximum specific growth rate (mmax) of 1.92 d-1, and half-saturated coefficient (ks) of 60.92mg/L were determined from these data. The mean dark FC decay rate coefficients, kd , at 35oC in the batch study …

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Sediment Transport In Wind-Exposed Shallow, Vegetated Aquatic Systems, Allen Michael Teeter Jan 2002

Sediment Transport In Wind-Exposed Shallow, Vegetated Aquatic Systems, Allen Michael Teeter

LSU Doctoral Dissertations

Ecosystems with submersed vegetation are relatively shallow, physically stable and of moderate hydrodynamic energy. Submersed vegetation affect hydrodynamic friction for currents and waves resulting in increased overall frictional loss. Seagrasses shelter the sediment bed and reduce wind-wave resuspension. Bed sheltering factors were estimated from previous flume data on Laguna Madre seagrass species. Data from Laguna Madre indicate that total suspended material levels for bare areas are about an order of magnitude higher than some areas with submersed vegetation. Waves in Laguna Madre at depths less than 2 m were found to be smaller than those expected for the same non-dimensional …

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Fast Scalable Visualization Techniques For Interactive Billion-Particle Walkthrough, Xinlian Liu Jan 2002

Fast Scalable Visualization Techniques For Interactive Billion-Particle Walkthrough, Xinlian Liu

LSU Doctoral Dissertations

This research develops a comprehensive framework for interactive walkthrough involving one billion particles in an immersive virtual environment to enable interrogative visualization of large atomistic simulation data. As a mixture of scientific and engineering approaches, the framework is based on four key techniques: adaptive data compression based on space-filling curves, octree-based visibility and occlusion culling, predictive caching based on machine learning, and scalable data reduction based on parallel and distributed processing. In terms of parallel rendering, this system combines functional parallelism, data parallelism, and temporal parallelism to improve interactivity. The visualization framework will be applicable not only to material simulation, …

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Artificial Peptides Containing Ca,A- Disubstituted Amino Acids: Synthesis, Conformational Studies, And Application As Β-Strand Mimics, Yanwen Fu Jan 2002

Artificial Peptides Containing Ca,A- Disubstituted Amino Acids: Synthesis, Conformational Studies, And Application As Β-Strand Mimics, Yanwen Fu

LSU Doctoral Dissertations

Short peptides containing Cα,α-dipropylglycine (Dpg) at alternating sequence positions were synthesized and examined for conformational behavior. Peptide assembly was performed using Fmoc-solid-phase chemistry where the coupling with PyAOP could be significantly enhanced at elevated temperature. Circular dichroism (CD) and NMR conformational studies revealed that incorporation of Dpg residues induced folded structures into peptides. It was observed that Dpg residues adopted helical conformation in a helix-promoting sequence. The resulting helical structure was comprised of consecutive β-turns whose structure was stabilized by salt bridge in aqueous solution. In this study, the preparation of sterically and polyfunctional Cα,α-disubstituted amino …

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Characterization Of Alligator, Ostrich And Emu Skins And Comparisons To Traditional Leathers, Terri M. Von Hoven Jan 2002

Characterization Of Alligator, Ostrich And Emu Skins And Comparisons To Traditional Leathers, Terri M. Von Hoven

LSU Doctoral Dissertations

Exotic skins and leathers have enjoyed a recent resurgence, as current fashion magazines illustrate. Louisiana would like to increase its niche in the exotic skins market by increasing alligator, ostrich and emu skin usage, mainly by inspiring designers to incorporate them into their repertoire. The possibilities are endless from apparel and trim to upholstery and other home furnishings to accessories; Louisiana exotic skins have significant market potential. In order to assist in these traditional textile applications, characterization of the various skin properties needs to be completed. The research was carried out in three stages. For the preliminary research, one emu …

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Log-Derived Cation Exchange Capacity Of Shaly Sands : Application To Hydrocarbon Detection And Drilling Optimization, Gamze Ipek Jan 2002

Log-Derived Cation Exchange Capacity Of Shaly Sands : Application To Hydrocarbon Detection And Drilling Optimization, Gamze Ipek

LSU Doctoral Dissertations

Researchers at Louisiana State University, LSU, have introduced several petrophysical models expressing the electric properties of shaly sands. These models, to be used for hydrocarbon detection, are based on the Waxman and Smits concept of supplementing the water conductivity with a clay counterions conductivity. The LSU models also utilize the Dual Water theory, which relates each conductivity term to a particular type of water, free and bound, each occupying a specific volume of the total pore space. The main difference between these models and the other shaly sand models is that the counterion conductivity is represented by a hypothetical sodium …

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Nutrient Reserves Of Lesser Scaup During Spring Migration In The Mississippi Flyway: A Test Of The Spring Condition Hypothesis, Michael J. Anteau Jan 2002

Nutrient Reserves Of Lesser Scaup During Spring Migration In The Mississippi Flyway: A Test Of The Spring Condition Hypothesis, Michael J. Anteau

LSU Master's Theses

The continental scaup population (lesser [Aythya affinis] and greater scaup [A. marila] combined) has declined markedly during the past 20 years, and has remained below the population goal of the North American Waterfowl Management Plan since 1985. One hypothesis explaining the scaup population decline states that reproductive success has decreased because females presently are arriving on breeding areas in poorer condition than that historically (Spring Condition Hypothesis [SCH]). I tested the SCH by comparing fresh body masses (FBMs) and nutrient reserves (lipid, protein, and mineral) of lesser scaup at 4 locations (Louisiana, Illinois, Minnesota, and Manitoba) in the Mississippi Flyway …

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Retention And Movement Of Reactive Chemicals In Soils, Hongxia Zhu Jan 2002

Retention And Movement Of Reactive Chemicals In Soils, Hongxia Zhu

LSU Doctoral Dissertations

Adsorption-desorption and transport behavior of pesticides are important processes that influence the amount retained by the soil and that which is susceptible to runoff or movement within the soil profile. Kinetic batch experiments were used to study the adsorption-desorption behavior of metolachlor (a non-ionic herbicide) and deltamethrin (a pyrethroid insectcide) in soils, and atrazine (a triazine) in sugarcane mulch residue. Miscible displacement experiments under steady flow conditions were carried out to examine the mobility of these pesticides in soils. Metolachlor adsorption and desorption by Sharkey clay soil(Very-fine, smectitic, thermic Chromic Epiaquerts) and Commerce silty loam soil (Fine-silty, mixed, superactive, nonacid, …

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Nitrification Rates In A Reversed-Flow, Spouted-Bed, Bioreactor Applied To Recirculating Aquaculture Systems, Jonathan Thomas Scott Jan 2002

Nitrification Rates In A Reversed-Flow, Spouted-Bed, Bioreactor Applied To Recirculating Aquaculture Systems, Jonathan Thomas Scott

LSU Master's Theses

The effects of media selection and organic loading on nitrification rates in a reversed-flow, three-phase, spouted-bed, bioreactor with draft-tube (A-1 Aquaculture Continuous-Cleaning Multifunctional Biofilter or CCMB) were studied. Experiments were conducted on three identical recirculating aquaculture systems (RAS) each having a CCMB unit with a unique plastic pelletized media and operated over five successive trials with varying components and operating conditions. Based upon organic loading, three of the five trials were grouped into two organic loading regimes of approximately 91 mg/L COD and 149 mg/L COD. Comparing nitrification rates against the three media types by organic loading showed that media …

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On The Stabilization And Regularization Of Rational Approximation Schemes For Semigroups, Simone Flory Jan 2002

On The Stabilization And Regularization Of Rational Approximation Schemes For Semigroups, Simone Flory

LSU Doctoral Dissertations

In this work we discuss consistency, stability and convergence of rational approximation methods for strongly continuous semigroups on Banach spaces. The Lax-Chernoff theorem shows that in this setting consistency and stability assumptions are necessary to obtain strong uniform convergence of approximation methods. We investigate rational approximation methods for strongly continuous semigroups and their consistency properties, with special emphasis on A-stable methods and Padé-type approximations. In particular, we discuss the stability and convergence properties of these schemes, including the stability of the well-known and widely used Backward-Euler and Crank-Nicolson Schemes. Furthermore, we modify stabilization techniques developed by Hansbo, Larsson, Luskin, Rannacher, …

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Geostatistical Shale Models For A Deltaic Reservoir Analog: From 3d Gpr Data To 3d Flow Modeling, Hongmei Li Jan 2002

Geostatistical Shale Models For A Deltaic Reservoir Analog: From 3d Gpr Data To 3d Flow Modeling, Hongmei Li

LSU Master's Theses

The effects of shales on fluid flow in marine-influenced lower delta-plain distributary channel deposits are investigated using a three-dimensional ground-penetrating radar (GPR) data volume from the Cretaceous-age Ferron sandstone at Corbula Gulch in central Utah, USA. Using interpreted GPR data, we formulate a geostatistical model of the dimensions, orientations, and geometries of the internal structure from the subaerial exposure surface down to about 12 m depth. The correlation function between GPR instantaneous amplitude and shale index is built after statistical calibration of the GPR attributes (amplitude) with well data (gamma ray logs). Shale statistics are computed from this correlation function. …

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Early-Middle Tertiary Deposition In The Corque Syncline, Altiplano Plateau, Bolivia, Brian A. Hampton Jan 2002

Early-Middle Tertiary Deposition In The Corque Syncline, Altiplano Plateau, Bolivia, Brian A. Hampton

LSU Master's Theses

Tertiary age rocks are exposed along north-south trending structures throughout the hinterland Altiplano plateau, central Andes. The east limb of the Corque syncline (SW Bolivia) contains the thickest and most continuous successions of late Eocene–Oligocene age non-marine strata (Potoco Formation) on the Altiplano. The Potoco is up to ~6500 m thick and has continuous exposure >103 km2 making it the thickest and most extensive remnant of the mid-Tertiary Altiplano basin. Basin fill during late Eocene–Oligocene time remains the most rapid and sustained period of deposition since Andean orogenesis, recording a long-term sediment accumulation rate of ~0.5 mm/my. The …

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Glacial Deposits, Vol. 30, 2001-2002, Department Of Geography-Geology Jan 2002

Glacial Deposits, Vol. 30, 2001-2002, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology

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Mixed-Symmetry Shell-Model Calculations In Nuclear Physics, Vesselin Gueorguiev Gueorguiev Jan 2002

Mixed-Symmetry Shell-Model Calculations In Nuclear Physics, Vesselin Gueorguiev Gueorguiev

LSU Doctoral Dissertations

Advances in computer technologies allow calculations in ever larger model spaces. To keep our understanding growing along with this growth in computational power, we consider a novel approach to the nuclear shell model. The one-dimensional harmonic oscillator in a box is used to introduce the concept of an oblique-basis shell-model theory. By implementing the Lanczos method for diagonalization of large matrices, and the Cholesky algorithm for solving generalized eigenvalue problems, the method is applied to nuclei. The mixed-symmetry basis combines traditional spherical shell-model states with SU(3) collective configurations. We test the validity of this mixed-symmetry scheme on 24Mg and …

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A Variable Response Time Lag Module For Car Following Models Using Fuzzy Set Theory, Yilmaz Hatipkarasulu Jan 2002

A Variable Response Time Lag Module For Car Following Models Using Fuzzy Set Theory, Yilmaz Hatipkarasulu

LSU Doctoral Dissertations

Since the 1950s, car following phenomena have been studied and analyzed, resulting in various models and algorithms. In general, the car following process has been defined as a stimulus-response relationship in which the driver of the following vehicle reacts to the actions of the lead vehicle after a time lag. One of the fundamental assumptions that underlie car following theory is that the driver response time lag is always a constant value for the driver at all times, regardless of level of detail of the model. Assumption of a constant time lag value introduces a number of broad assumptions however, …

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Synthesis And Study Of New Materials For The Visual Detection Of Biomolecules, Ming He Jan 2002

Synthesis And Study Of New Materials For The Visual Detection Of Biomolecules, Ming He

LSU Doctoral Dissertations

The visual determination of saccharides has been of interest for well over a century. Sugars are a relatively challenging class of compounds to analyze. They exhibit great structural similarity as well as transparency in the visible region. The sensing of specific saccharides could aid the monitoring of disease or industrial fermentation products. Herein I present new methods allowing for simple and rapid visual detection of sialic acid, fructose and a homologous series of prototypical neutral oligosaccharides, the linear maltodextrins, containing up to seven glucose residues. The new methods allow for selective color detection of fructose in a large excess of …

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Synthesis, Characterization, And Applications Of Novel Pseudostationary Phases In Micellar Capillary Electrophoresis For Separation Of Chiral And Archiral Compounds H[Electronic Resource], Cevdet Akbay Jan 2002

Synthesis, Characterization, And Applications Of Novel Pseudostationary Phases In Micellar Capillary Electrophoresis For Separation Of Chiral And Archiral Compounds H[Electronic Resource], Cevdet Akbay

LSU Doctoral Dissertations

The research presented in this dissertation involves the synthesis, characterization, and the use of novel surfactants, including both micelles and vesicles, as pseudostationary phases in micellar capillary electrophoresis (MCE) for the separation of achiral and chiral compounds. Separation of environmental pollutants such as 2 to 6-ring polycyclic aromatic hydrocarbons (PAHs) was achieved using poly(sodium undecylenic sulfate). A baseline separation of all 16 PAHs was possible for the first time in MCE by a single-surfactant system. In addition, a surfactant with a phosphated head group, i.e., di(2-ethylhexyl)phosphate (DEHP), was also introduced as a novel pseudostationary phase for separation of 21 weakly …

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Experience-Based Language Acquisition: A Computational Model Of Human Language Acquisition, Brian Edward Pangburn Jan 2002

Experience-Based Language Acquisition: A Computational Model Of Human Language Acquisition, Brian Edward Pangburn

LSU Doctoral Dissertations

Almost from the very beginning of the digital age, people have sought better ways to communicate with computers. This research investigates how computers might be enabled to understand natural language in a more humanlike way. Based, in part, on cognitive development in infants, we introduce an open computational framework for visual perception and grounded language acquisition called Experience-Based Language Acquisition (EBLA). EBLA can “watch” a series of short videos and acquire a simple language of nouns and verbs corresponding to the objects and object-object relations in those videos. Upon acquiring this protolanguage, EBLA can perform basic scene analysis to generate …

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On Properties Of Linear Control Systems On Lie Groups, Fabiana Cardetti Jan 2002

On Properties Of Linear Control Systems On Lie Groups, Fabiana Cardetti

LSU Doctoral Dissertations

In this work we study controllability properties of linear control systems on Lie groups as introduced by Ayala and Tirao in [AT99]. A linear control system _x0006_Σ Lie group G is defined by x' = X(x) + Σkj=1 ujYj(x), where the drift vector field X is an infinitesimal automorphism, uj are piecewise constant functions, and the control vectors Yj are left-invariant vector fields. Properties for the flow of the infinitesimal automorphism X and for the reachable set defined by _x0006_Σ are presented in Chapter 3. Under a condition similar to the Kalman …

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Predicting Electron Insert Output Factors At Nominal And Extended Source To Surface Distance, Ahmet Bulut Jan 2002

Predicting Electron Insert Output Factors At Nominal And Extended Source To Surface Distance, Ahmet Bulut

LSU Master's Theses

Two Varian linear accelerators were used to test the modified sector-integration method. This method can predict the electron insert factor for arbitrary inserts at different source to surface distances (SSD). The effective source distances (SSDeff) and insert factors (IF) for several accelerators are compared. The relationship of IF and SSDeff for machine type, energy, cone size, insert size and SSD is presented. The results were fed into the electron output determination module of an existing monitor unit calculator (MUCalc) which uses the modified sector integration method. Prediction and measurements were compared for various clinical inserts at several …

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