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The Macho Project Large Magellanic Cloud Variable Star Inventory. Iv. New R Coronae Borealis Stars, C. Alcock, R. A. Allsman, D. R. Alves, T. S. Axelrod, A. Decker, D. P. Bennett, G. C. Clayton, K. H. Cook, K. C. Freeman, K. Griest, J. A. Guern, D. Kilkenny, M. J. Lehner, S. L. Marshall, D. Minniti, B. A. Peterson, M. R. Pratt, P. J. Quinn, A. W. Rodgers, C. W. Stubbs, W. Sutherland, D. Welch Jan 1996

The Macho Project Large Magellanic Cloud Variable Star Inventory. Iv. New R Coronae Borealis Stars, C. Alcock, R. A. Allsman, D. R. Alves, T. S. Axelrod, A. Decker, D. P. Bennett, G. C. Clayton, K. H. Cook, K. C. Freeman, K. Griest, J. A. Guern, D. Kilkenny, M. J. Lehner, S. L. Marshall, D. Minniti, B. A. Peterson, M. R. Pratt, P. J. Quinn, A. W. Rodgers, C. W. Stubbs, W. Sutherland, D. Welch

Faculty Publications

We report the discovery of two new R Coronae Borealis (RGB) stars in the LMC using the MACHO project photometry database. The identification of both stars has been confirmed spectroscopically. One is a cool RGB star (Teff ∼ 5000 K), characterized by very strong Swan bands of C2 and violet bands of CN, and weak or absent Bahner lines, G band, and 12C13C bands. The second star is an example of a hot RGB star, of which only three were previously known to exist in the Galaxy and none in the LMC. Its spectrum is characterized by several G n …

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Lattice Dynamics Of Ii-Vi Materials Using The Adiabatic Bond-Charge Model, B. Rajput, D. Browne Jan 1996

Lattice Dynamics Of Ii-Vi Materials Using The Adiabatic Bond-Charge Model, B. Rajput, D. Browne

Faculty Publications

We extend the adiabatic bond-charge model, originally developed for group IV semiconductors and III-V compounds, to study phonons in more ionic II-VI compounds with a zinc-blende structure. Phonon spectra, density of states, and specific heats are calculated for six II-VI compounds and compared with both experimental data and the results of other models. We show that the six-parameter bond-charge model gives a good description of the lattice dynamics of these materials. We also discuss trends in the parameters with respect to the ionicity and metallicity of these compounds. © 1996 The American Physical Society.

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First-Principles Lcgo Calculation Of The Magneto-Optical Properties Of Nickel And Iron, Neeraj Mainkar, D. Browne, J. Callaway Jan 1996

First-Principles Lcgo Calculation Of The Magneto-Optical Properties Of Nickel And Iron, Neeraj Mainkar, D. Browne, J. Callaway

Faculty Publications

We report a first-principles, self-consistent, all-electron, linear combination of Gaussian orbitals calculation of a comprehensive collection of magneto-optical properties of nickel and iron based on density-functional theory. Among the many magneto-optical effects, we have studied the equatorial Kerr effect for absorption in the optical as well as soft-x-ray region, where it is called x-ray magnetic linear dichroism. In the optical region the effect is of the order of 2% while in the x-ray region it is of the order of 1% for the incident angles considered. In addition, the polar Kerr effect, x-ray magnetic circular dichroism, and total x-ray absorption …

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The Russian-American Gallium Experiment (Sage) Cr Neutrino Source Measurement, J. N. Abdurashitov, V. N. Gavrin, S. V. Girin, V. V. Gorbachev, T. V. Ibragimova, A. V. Kalikhov, N. G. Khairnasov, T. V. Knodel, V. N. Kornoukhov, I. N. Mirmov, A. A. Shikhin, E. P. Veretenkin, V. M. Vermul, V. E. Yants, G. T. Zatsepin, T. J. Bowles, J. S. Nico, W. A. Teasdale, D. L. Wark, M. L. Cherry, V. N. Karaulov, V. L. Levitin, V. I. Maev, P. I. Nazarenko, V. S. Shkol-Nik, N. V. Skorikov, B. T. Cleveland, T. Daily, R. Davis, K. Lande, C. K. Lee, P. W. Wildenhain, Y. U.S. Khomyakov Jan 1996

The Russian-American Gallium Experiment (Sage) Cr Neutrino Source Measurement, J. N. Abdurashitov, V. N. Gavrin, S. V. Girin, V. V. Gorbachev, T. V. Ibragimova, A. V. Kalikhov, N. G. Khairnasov, T. V. Knodel, V. N. Kornoukhov, I. N. Mirmov, A. A. Shikhin, E. P. Veretenkin, V. M. Vermul, V. E. Yants, G. T. Zatsepin, T. J. Bowles, J. S. Nico, W. A. Teasdale, D. L. Wark, M. L. Cherry, V. N. Karaulov, V. L. Levitin, V. I. Maev, P. I. Nazarenko, V. S. Shkol-Nik, N. V. Skorikov, B. T. Cleveland, T. Daily, R. Davis, K. Lande, C. K. Lee, P. W. Wildenhain, Y. U.S. Khomyakov

Faculty Publications

The solar neutrino capture rate measured by SAGE is well below that predicted by solar models. To check the overall experimental efficiency, we exposed 13 tonnes of Ga metal to a reactor-produced 517 kCi source of 51Cr. The ratio of the measured production rate to that predicted from the source activity is 0.95+/-0.11\(stat\)+0.05/-0.08\(syst\). This agreement verifies that the experimental efficiency is measured correctly, establishes that there are no unknown systematic errors at the 10% level, and provides considerable evidence for the reliability of the solar neutrino measurement. © 1996 The American Physical Society.

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Isotopic Evolution Of The Tonga Arc During Lau Basin Rifting; Evidence From The Volcaniclastic Record, Peter D. Clift, Pieter Z. Vroon Jan 1996

Isotopic Evolution Of The Tonga Arc During Lau Basin Rifting; Evidence From The Volcaniclastic Record, Peter D. Clift, Pieter Z. Vroon

Faculty Publications

New Pb, Sr and Nd isotope data from volcaniclastic sediments recovered from the Tonga forearc and Lau Basin permit the isotopic evolution of a section of this arc system, next to the modern island of Ata, to be traced through the backarc basin rifting process from 7·0 Ma to the present. The new data suggest that the isotopic character of the mantle wedge remains constant, and of Pacific mid-ocean ridge basalt (MORB) character, during the early rifting phase. The isotopic evidence supports trace element data in showing an increase in the sediment contribution to arc petrogenesis about 2-3 m.y. after …

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Effect Of Mutations On The Sensitivity Of Human Beta-Cell Glucokinase To Liver Regulatory Protein, M. Veiga-Da-Cunha, L. Z. Xu, Y. H. Lee, D. Marotta, S. J. Pilkis, E. Van Schaftingen Jan 1996

Effect Of Mutations On The Sensitivity Of Human Beta-Cell Glucokinase To Liver Regulatory Protein, M. Veiga-Da-Cunha, L. Z. Xu, Y. H. Lee, D. Marotta, S. J. Pilkis, E. Van Schaftingen

Faculty Publications

Human beta-cell glucokinase and its liver counterpart displayed a half-saturating concentration of glucose (S0.5) of about 8 mmol/l and a Hill coefficient of 1.7, and were as sensitive to inhibition by the rat liver regulatory protein as the rat liver enzyme. These results indicate that the N-terminal region of glucokinase, which differs among these three enzymes, is not implicated in the recognition of the regulatory protein. They also suggest that the regulatory protein, or a related protein, could modulate the affinity of glucokinase for glucose in beta cells. We have also tested the effect of several mutations, many of which …

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Relationship Between Birth Weight And Awake Blood Pressure In Children And Adolescents In Absence Of Intrauterine Growth Retardation, Empar Lurbe, Josep Redon, Vicente Alvarez, Ramon Durazo, Ana Gomez, Jose Tacons, Richard S. Cooper Jan 1996

Relationship Between Birth Weight And Awake Blood Pressure In Children And Adolescents In Absence Of Intrauterine Growth Retardation, Empar Lurbe, Josep Redon, Vicente Alvarez, Ramon Durazo, Ana Gomez, Jose Tacons, Richard S. Cooper

Faculty Publications

This study was designed to examine the relationship between birth weight (BW) and ambulatory blood pressure in children and adolescents, born at term in absence of intrauterine growth retardation. Twenty-four hour ambulatory blood pressure monitoring (ABPM) was performed on 332 children (150 boys), aged from 6 to 16 years. Subjects were stratified by BW tertiles and age. ABPM was performed using SpaceLabs 90207 monitor during a regular school day. Blood pressure (BP) was measured every 20 min from 06:00 to 24:00, and thereafter every 30 min. Means of systolic BP (SBP) and diastolic BP (DBP) during 24 h, daytime (08:00 …

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Multigrid Methods For Parameter Dependent Problems, Susanne C. Brenner Jan 1996

Multigrid Methods For Parameter Dependent Problems, Susanne C. Brenner

Faculty Publications

Multigrid methods for parameter dependent problems are discussed. The contraction numbers of the algorithms are proved within a unifying framework to be bounded away from one, independent of the parameter and the mesth levels. Examples include the pure displacement and pure traction boundary value problems in planar linear elasticity, the Timoshenko beam problem, and the Reissner-Mindlin plate problem.

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The Spirit Of Poetry And The Importance Of Joy Shelley's Revolutionary Animism, John Freeman Jan 1996

The Spirit Of Poetry And The Importance Of Joy Shelley's Revolutionary Animism, John Freeman

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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The Christian Humanism Of Anne Bronte, James Woelfel Jan 1996

The Christian Humanism Of Anne Bronte, James Woelfel

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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Between The Glass And The Hand The Eye In Margaret Cavendish's Blaiing World, Anna Battigelli Jan 1996

Between The Glass And The Hand The Eye In Margaret Cavendish's Blaiing World, Anna Battigelli

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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Book Review Corner Jan 1996

Book Review Corner

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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"The Primrose Way" John Bunyan's The Lifo Death Of Mr, Badman And The Picaresque, James G. Randall Jan 1996

"The Primrose Way" John Bunyan's The Lifo Death Of Mr, Badman And The Picaresque, James G. Randall

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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How To (Mis)Read Hogarth Or, Ekphrasis Galore, Peter Wagner Jan 1996

How To (Mis)Read Hogarth Or, Ekphrasis Galore, Peter Wagner

1650-1850: Ideas, Aesthetics, and Inquiries in the Early Modern Era

No abstract provided.

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Rigorous Solution Of The Quantum Einstein Equations, Rodolfo Gambini, Jorge Pullin Jan 1996

Rigorous Solution Of The Quantum Einstein Equations, Rodolfo Gambini, Jorge Pullin

Faculty Publications

We show that the second coefficient of the Conway knot polynomial is annihilated by the Hamiltonian constraint of canonically quantized general relativity in the loop representation. The calculations are carried out in a fully regularized lattice framework. Crucial to the calculation is the explicit form of the skein relations of the second coefficient, which relate it to the Gauss linking number. Contrary to the lengthy formal continuum calculation, the rigorous lattice version can be summarized in a few pictures. © 1996 The American Physical Society.

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Analytic Approximations To The Spacetime Of A Critical Gravitational Collapse, Richard H. Price, Jorge Pullin Jan 1996

Analytic Approximations To The Spacetime Of A Critical Gravitational Collapse, Richard H. Price, Jorge Pullin

Faculty Publications

We present analytic expressions that approximate the behavior of the spacetime of a collapsing spherically symmetric scalar field in the critical regime first discovered by Choptuik. We find that the critical region of spacetime can usefully be divided into a "quiescent," an "oscillatory," and a moving "transition" region. We find that in the quiescent and oscillatory regions the critical solution can be well approximated by a flat spacetime scalar field solution. A qualitative nonlinear matching of the solutions across the transition region yields the right order of magnitude for the oscillations of the discretely self-similar critical solution found by Choptuik. …

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Colliding Black Holes: How Far Can The Close Approximation Go?, Reinaldo J. Gleiser, Carlos O. Nicasio, Richard H. Price, Jorge Pullin Jan 1996

Colliding Black Holes: How Far Can The Close Approximation Go?, Reinaldo J. Gleiser, Carlos O. Nicasio, Richard H. Price, Jorge Pullin

Faculty Publications

We study the head-on collision of two equal-mass momentarily stationary black holes, using black hole perturbation theory up to second order. Compared to first-order results, this significantly improves agreement with numerically computed wave forms and energy. Much more important, second-order results correctly indicate the range of validity of perturbation theory. This use of second-order corrections to provide “error bars” to the first-order results makes perturbation theory a viable tool for providing benchmarks for numerical relativity in more generic collisions and, in some range of collision parameters, for supplying wave form templates for gravitational wave detection. © 1996 The American Physical …

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Detachment Force And Fruit Characteristics Of Tabasco Pepper At Several Stages Of Development, Carl E. Motsenbocker Jan 1996

Detachment Force And Fruit Characteristics Of Tabasco Pepper At Several Stages Of Development, Carl E. Motsenbocker

Faculty Publications

Field and greenhouse studies examined the fruit detachment force (FDF) and fruit and pedicel characteristics of two lines of tabasco pepper (Capsicum frutescens L.) at several stages of maturity. The detachment force of red-mature 'McIlhenny Select' fruit at the calyx-fruit detachment area was lower than that of less mature fruit stages. The force required to detach red-mature Hard Pick (HP) tabasco fruit was higher than that of red-mature 'McIlhenny Select' fruit in the field and greenhouse. The fruit detachment force of red field-grown HP fruit was higher, and in the greenhouse was lower, than that of green or breaker fruit. …

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Effects Of Organic Waste Amendments, Herbicides, And Weed Hosts On Pythium Root Rot Of Sugarcane., Nimal Mudiyans Dissanayake Jan 1996

Effects Of Organic Waste Amendments, Herbicides, And Weed Hosts On Pythium Root Rot Of Sugarcane., Nimal Mudiyans Dissanayake

LSU Historical Dissertations and Theses

Three objectives that could lead to improved understanding and management of Pythium root rot of sugarcane were addressed. First, the potential of amending soil with different organic wastes to suppress root rot was evaluated, and the biological and chemical properties of wastes that may contribute to disease suppression were identified. Secondly, herbicide interactions with root rot affecting sugarcane growth were assessed. Finally, the role of weeds in disease epidemiology was investigated. Greenhouse and laboratory studies indicated soil amendment with some organic wastes offers a sustainable disease management option through biological control. Amendment with different wastes had variable effects. Sewage sludge, …

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Factors Controlling The Impacts Of South Louisiana Crude Oil On The Vegetation And Revegetation Of Coastal Wetlands., Qianxin Lin Jan 1996

Factors Controlling The Impacts Of South Louisiana Crude Oil On The Vegetation And Revegetation Of Coastal Wetlands., Qianxin Lin

LSU Historical Dissertations and Theses

The impacts of south Louisiana crude oil on three types of marsh, salt, brackish, and freshwater, dominated by Spartina alterniflora, S. patens, and Sagittaria lancifolia, respectively, were studied in the greenhouse. The influence of a number of factors such as marsh type, plant species, oil dosage, oil coverage, soil composition, leaf surface structure, season and meteorological conditions, on the impact of crude oil to marsh vegetation and revegetation were investigated. Vegetative sensitivity to south Louisiana crude oil increased in the order of S. lancifolia, S. alterniflora, and S. patens. Photosynthetic rates, stem densities, and the regrowth of aboveground biomass for …

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Magneto-Optical Properties Of Cubic Ferromagnetic Metals., Neeraj Arvind Mainkar Jan 1996

Magneto-Optical Properties Of Cubic Ferromagnetic Metals., Neeraj Arvind Mainkar

LSU Historical Dissertations and Theses

I present a first principles, all electron, linear combination of Gaussian orbitals calculation of a comprehensive collection of magneto-optical properties of the cubic ferromagnetic metals nickel, iron and cobalt based on density functional theory. Among the many magneto-optical effects, this is the first ab initio study of the equatorial Kerr effect for absorption in the optical as well as the X-ray region, where it is called the X-ray magnetic linear dichroism. I find that in the optical region, this effect is of the order of 2% while in the X-ray region, it is of the order of 1% for the …

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Crystal Plasticity Model With Back Stress Evolution., Wei Huang Jan 1996

Crystal Plasticity Model With Back Stress Evolution., Wei Huang

LSU Historical Dissertations and Theses

In this work, two backstress models and a modified yield criterion for crystalline materials are proposed. The proposed work is for the identification of texture development in metals when subjected to large deformation processes such as rolling, extrusion, stamping and deep drawing, etc. These models are incorporated into a numerical procedure similar to the approaches by Asaro (1983), Peirce et al. (1983), Nemat-Nasser (1983), and Rashid and Nemat-Nasser (1992). Also, similar to their approaches, a two-dimensional crystal structure is used for a feasibility study of the model by solving a simple shear problem. More importantly, the proposed formulations are strain …

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Composted Municipal Waste And Fertilizer Effects On Soils And Sugarcane., Xianliang Wan Jan 1996

Composted Municipal Waste And Fertilizer Effects On Soils And Sugarcane., Xianliang Wan

LSU Historical Dissertations and Theses

Application of composted municipal waste to agricultural lands has potential benefits to improve soil fertility and crop yield. It may lead to accumulation of heavy metals within soils and leaching of nutrients and heavy metals into the ground water. The objectives of this study were to investigate: (1) the effects of composted municipal waste and fertilizer on soil chemical properties and sugarcane elemental uptake and yield; and (2) the leachability of elements in compost amended soils. Results of three field experiments from a Baldwin silty clay loam and a Memphis silt loam showed that compost application at $\ge$33.6 Mg/ha increased …

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Synthesis Of Uv/X-Ray Sensitive Polymers And Their Applications As Resists., Jack Dean Davies Jan 1996

Synthesis Of Uv/X-Ray Sensitive Polymers And Their Applications As Resists., Jack Dean Davies

LSU Historical Dissertations and Theses

Aliphatic polycarbonates were synthesized by condensation of the bischloroformate of 2,2,4,4-tetramethyl-1,3-cyclobutanediol with cyclic aliphatic diols. Polycarbonates that lacked flexible methylene units in the backbone processed T$\sb{\rm g}\ >$ 139$\sp\circ$C. Copolycarbonates acted as resists when combined with cobalt(III)-am(m)ine tetraphenylborate complexes which act as photointiators, with tetraphenylborate serving as counter anion. The photoinitiator liberates either ammonia or ethylene diamine base upon UV exposure and the polycarbonate backbone is subject to nucleophilic attack at the carbonyl linkage by the base. Image tone was dependent on the base used. Amine complexes, Co(NH$\sb3)\sb6\sp{3+}$ effected a positive tone due to ammonia induced main chain degradation at …

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Active Tectonics Of The Northeastern Mojave Desert, California., David F. Macconnell Jan 1996

Active Tectonics Of The Northeastern Mojave Desert, California., David F. Macconnell

LSU Historical Dissertations and Theses

This study has led to an improved understanding of the active tectonics and seismic hazards of the northeastern Mojave Desert region and has provided a means with which to assess regional strain models proposed by previous workers. Primary data sets include published and unpublished geologic maps, Landsat Thematic Mapper multi-spectral imagery, SPOT panchromatic imagery as well as hand-held ground and aerial photographs (panchromatic, color and color-infrared), color video, digital topography, gravity, seismicity and paleomagnetic data. Prior to analysis, data sets were organized into a geographic information system implemented on a UNIX workstation. This allowed for the simultaneous visualization of combinations …

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The Cytoplasmic N,N'-Diacetylchitobiase Gene From Vibrio Parahaemolyticus: Sequence Analysis, Protein Secretion, And Secretion System Development., Michael Hongli Wu Jan 1996

The Cytoplasmic N,N'-Diacetylchitobiase Gene From Vibrio Parahaemolyticus: Sequence Analysis, Protein Secretion, And Secretion System Development., Michael Hongli Wu

LSU Historical Dissertations and Theses

The nucleotide sequence of the gene encoding the cytoplasmic $N,N\sp\prime$-diacetylchitobiase from Vibrio parahaemolyticus has been determined. The deduced peptide sequence surprisingly has minimum evolutionary relationship to two other reported $N,N\sp\prime$-diacetylchitobiases from vibrios, except for highly conserved regions which are also homologous with lysosomal beta-hexosaminidases from eukaryotes including humans. In contrast, the other two sequenced chitobiases from vibrios are much more closely related to each other. This 85 kDa cytoplasmic protein, as revealed from the sequence, appears to be a unique protein, lacking a signal sequence and genetically distant from other known enzymes of similar function. This is consistent with its …

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Scale, Resolution And Resampling: Representation And Analysis Of Remotely Sensed Landscapes Across Scale In Geographic Information Systems., Stephanie Jean Weigel Jan 1996

Scale, Resolution And Resampling: Representation And Analysis Of Remotely Sensed Landscapes Across Scale In Geographic Information Systems., Stephanie Jean Weigel

LSU Historical Dissertations and Theses

Earth system scientists are increasingly using the technologies of Geographic Information Systems (GIS) and Remote Sensing (RS) in their analyses of earth system processes and patterns. These investigations take place over a wide range of scales, from the local to the global. Global change researchers focus on both the physical and human dimensions of changes in the earth's landscapes, which occur across a range of scales and may be scale dependent. The way in which landscapes are represented in GIS and RS, using specific spatial data models and data spatial resolutions, affects the subsequent analyses that can be performed. Optimally …

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Factors Influencing Completion Status Of Undergraduate Nursing Students Who Initiate Progression Appeals., Karen Diane Hadskey Blanchard Jan 1996

Factors Influencing Completion Status Of Undergraduate Nursing Students Who Initiate Progression Appeals., Karen Diane Hadskey Blanchard

LSU Historical Dissertations and Theses

The purpose of this descriptive research study was to determine the existence of predictors for success of nursing students who are granted appeals, based on special circumstances, by the University Progression and Retention Committee of Southeastern Louisiana University. This study investigated demographics (age, marital status, gender, race, residence, semester of appeal, and educational background) of 302 nursing students from Southeastern Louisiana University (January 1988, to May 1995) that appealed to the Progression and Retention Committee of the university to continue in the nursing program. Success predictor criteria provided to nursing faculty and students can be used as a positive resource …

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Reverse Engineering Low-Level Design Patterns From Object-Oriented Code., Chandra Shrivastava Jan 1996

Reverse Engineering Low-Level Design Patterns From Object-Oriented Code., Chandra Shrivastava

LSU Historical Dissertations and Theses

The purpose of this research is to develop and automatically extract an abstract representation model of object-oriented (abbreviated as OO) software systems that captures the structure of the system and code dependencies, in order to aid maintenance. The research resulted in the development of two abstract representation models--the low-level design pattern (LLDP) abstract model and the low-level software architecture (LLSA) abstract model. The LLDP model is at a higher level of abstraction than the LLSA model. The LLSA model acts as an intermediate representation between the LLDP model and an OO software system. The design of the LLSA and LLDP …

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Automatic Data And Computation Mapping For Distributed-Memory Machines., Isidoro Couvertier-Reyes Jan 1996

Automatic Data And Computation Mapping For Distributed-Memory Machines., Isidoro Couvertier-Reyes

LSU Historical Dissertations and Theses

Distributed memory parallel computers offer enormous computation power, scalability and flexibility. However, these machines are difficult to program and this limits their widespread use. An important characteristic of these machines is the difference in the access time for data in local versus non-local memory; non-local memory accesses are much slower than local memory accesses. This is also a characteristic of shared memory machines but to a less degree. Therefore it is essential that as far as possible, the data that needs to be accessed by a processor during the execution of the computation assigned to it reside in its local …

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