Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

227,415 Full-Text Articles 293,931 Authors 70,376,868 Downloads 429 Institutions

All Articles in Physical Sciences and Mathematics

Faceted Search

227,415 full-text articles. Page 6576 of 6605.

Comprehensive Study Of Parameters For Volumetric Modulated Arc Therapy (Vmat) Treatment Planning, Catharine Elizabeth Talbert 2010 Louisiana State University and Agricultural and Mechanical College

Comprehensive Study Of Parameters For Volumetric Modulated Arc Therapy (Vmat) Treatment Planning, Catharine Elizabeth Talbert

LSU Master's Theses

Volumetric modulated arc therapy (VMAT) is a rotational IMRT technique that uses a radiotherapy linear accelerator gantry with a dynamic MLC, variable dose rate, and variable gantry speed. These new degrees of freedom of VMAT delivery introduced complexities for treatment planning, and Pinnacle3 SmartArc treatment module was recently developed as a solution. However, it was unclear how varying each SmartArc parameter affected the resulting plan quality. The purpose of this study was to systematically examine all planning parameters and quantify the effect of varying each on the quality of a reference plan. Parameters were separated into two categories: commissioning parameters ...


Evaluating Remote Setting Techniques For Oyster (Crassostrea Virginica) Seed Production In Louisiana, Victoria D. Ippolito 2010 Louisiana State University and Agricultural and Mechanical College

Evaluating Remote Setting Techniques For Oyster (Crassostrea Virginica) Seed Production In Louisiana, Victoria D. Ippolito

LSU Master's Theses

Research was conducted to implement remote setting technology for the commercial- scale production of oysters on alternative cultch material in Louisiana. Genetic research has created an enhanced oyster stock for commercial cultivation. Since the Louisiana oyster industry relies on natural seed production for product, they are unable to utilize these new advances and are never guaranteed a reliable source of oyster seed. Remote setting is one way of producing a consistent supply of genetically improved oysters. Cultch material for oyster settlement is a limiting resource. Several alternatives to clamshell have been explored. The objectives of this study are: (1) test ...


Project Explorations And Student Learning In Geometry, Verna Marie Richard 2010 Louisiana State University and Agricultural and Mechanical College

Project Explorations And Student Learning In Geometry, Verna Marie Richard

LSU Master's Theses

The purpose of this study was to examine the structural framework of the EBRPSS 8th Grade Mathematics Comprehensive Curriculum and to compare its effectiveness to a set of project-based lessons that I created for “Unit 4: Measurement and Geometry”. Two classes participated in this study. Pretest and Posttest scores were analyzed to determine if there was a significant advantage to using my supplements. Results of the analysis revealed that there was an advantage to using the supplements, in spite of the time shortage. Hopefully, the supplements implemented in this study will serve as a model for teaching “Unit 4: Measurement ...


Correlation Of Defaults In Complex Portfolios Using Copula Techniques, Adam Lodygowski 2010 Louisiana State University and Agricultural and Mechanical College

Correlation Of Defaults In Complex Portfolios Using Copula Techniques, Adam Lodygowski

LSU Master's Theses

This work, dealing with the correlation between subportfolios in more complex portfolios, begins with a brief survey of the necessary theoretical background. The basic statistical and probabilistic concepts are reviewed. The notion of copulas is introduced along with the fundamental theorem of Sklar. After this background a numerical procedure and code are developed for correlated defaults in multiple correlated portfolio. Further on, interesting results regarding the impact of changes in correlation on the portfolio performance are investigated in the simulations. The most valuable observations regarding the expected default ratios of two subportfolios considered jointly are presented and explained with particular ...


Habitat Use, Movements And Spring Migration Chronology And Corridors Of Female Gadwalls That Winter Along The Louisiana Gulf Coast, Jacob M. Gray 2010 Louisiana State University and Agricultural and Mechanical College

Habitat Use, Movements And Spring Migration Chronology And Corridors Of Female Gadwalls That Winter Along The Louisiana Gulf Coast, Jacob M. Gray

LSU Master's Theses

The Louisiana Gulf Coast is an important wintering area for North American gadwall (Anas strepera). Conservation of winter habitat is a top priority of the Gulf Coast Joint Venture. Quantitative estimates of habitat use by wintering gadwall would help improve energetic demand models and subsequent estimates of habitat requirements. I used satellite telemetry (PTTs) to estimate winter habitat and refuge uses, spring migration chronology and corridors, as well as inter- and intra-regional winter movements of females. I used a split-plot MANOVA to evaluate the effects of individual females, female age, winter, hunt periods within winter, time of day, and all ...


Impacts Of Marsh Loss And Fragmentation On Microhabitat Use By Estuarine Nekton In Southwest Louisiana, John Alexander Gordon 2010 Louisiana State University and Agricultural and Mechanical College

Impacts Of Marsh Loss And Fragmentation On Microhabitat Use By Estuarine Nekton In Southwest Louisiana, John Alexander Gordon

LSU Master's Theses

In Louisiana, the extensive loss and fragmentation of coastal marshes has prompted inquires into the impacts these processes may have on estuarine-dependant nekton. To date, research on nekton response to marsh loss and fragmentation has been limited to landscape-level studies which focus on the relationship between nekton productivity and the availability of marsh edge. These studies have relied on the assumption that marsh edges provide the same level of support to nekton regardless of the degree of surrounding marsh loss or fragmentation. This study tested this assumption by investigating the impacts of marsh loss and fragmentation on marsh-edge characteristics and ...


Palynological Analysis Of Tiger And Trinity Shoals, Louisiana Continental Shelf, Russell Ryan Crouch 2010 Louisiana State University and Agricultural and Mechanical College

Palynological Analysis Of Tiger And Trinity Shoals, Louisiana Continental Shelf, Russell Ryan Crouch

LSU Master's Theses

Forty sediment samples taken from twenty-six vibracores collected from Holocene shoals (Tiger and Trinity) were processed for palynomorphs and analyzed to characterize the terrestrial and marine paleo-environments of southern Louisiana at the time of deposition of each shoal. Abundant and diverse pollen assemblages were recovered while marine microplankton were sparse (< 2% relative abundance). Pollen species were grouped by plants of similar environmental significances including arboreal, non-arboreal, aquatic, and shrub categories. Palynological signals were compared in detail between each core, as well as along strike and dip transects, to help determine whether or not these shoals were deposited coevally or in distinct depositional cycles. Evidence shows that Tiger and Trinity Shoals carry remarkably similar palynological profiles, indicating that sediments of these shoals areS from the same source, and that deposition extended over an interval of time such that climate change was not sufficient enough to alter the vegetation response (hence palynological signal). Pollen profiles show source sediments are predominantly from the lower Mississippi River drainage basin and exhibit species similar to those present in modern Louisiana coastal marshes and swamps (i.e., Taxodium distichum, Cyperaceae, Graminae, Chenopodiaceae, and Asteraceae), and coastal to upland hardwood forests of the Mississippi River alluvial valley (i.e., Pinus, Quercus, Carya, and Liquidambar styraciflua).


Grade Level Expectations: Do They Prepare Students For Introductory College Chemistry?, Micah M. Davies 2010 Louisiana State University and Agricultural and Mechanical College

Grade Level Expectations: Do They Prepare Students For Introductory College Chemistry?, Micah M. Davies

LSU Master's Theses

This study investigates whether the Grade Level Expectations (GLEs) as outlined by the Louisiana Department of Education prepare students for introductory college level chemistry. A sample of 135 students in Dr. Watkins fall 2009 CHEM 1201 classes were tested for correlations between knowledge of the GLEs (chemical concept inventory pre-test and post-test score and normalized gain) and performance in CHEM 1201 (average exam score and final exam score). No significant correlations were found between any of these variables. For further analysis, students were grouped into two groups, in-state public school students and out-of-state/private school students. It was assumed that ...


Predicting First Year Seedling Survival From Quality Distributions Of Bareroot Seedlings And Microsites, Puskar Nath Khanal 2010 Louisiana State University and Agricultural and Mechanical College

Predicting First Year Seedling Survival From Quality Distributions Of Bareroot Seedlings And Microsites, Puskar Nath Khanal

LSU Master's Theses

Seeding survival has been a continuing problem since the start of the commercial pine plantation in 1950s. The first-year survival of bare-root loblolly pine seedlings at intensively prepared sites in Louisiana has reached a survival plateau of 75 to 85 % with an average of almost 80 %. The major hypothesis of this research was that the survival plateau is a function of the interaction between the frequency distribution of seedling quality and the frequency distribution of microsite quality. This study examined bare-root seedlings and microsite variation, and analyzed the possible options to increase the first-year seedling survival. The study was approached ...


An Assessment Of Factors Affecting Population Growth Of The Mountain Plover, Stephen J. Dinsmore, Michael B. Wunder, Victoria J. Dreitz, Fritz L. Knopf 2010 Iowa State University

An Assessment Of Factors Affecting Population Growth Of The Mountain Plover, Stephen J. Dinsmore, Michael B. Wunder, Victoria J. Dreitz, Fritz L. Knopf

Natural Resource Ecology and Management Publications

Effective conservation measures should target the most sensitive life history attributes of a species, assuming they are responsive to potential management actions. The Mountain Plover (Charadrius montanus) is a species of conservation concern with a patchy breeding distribution in western North America. Plovers prefer areas with short vegetation, bare ground, and disturbance for nesting. Current management tools, including grazing and burning, have been used to attract plovers and enhance nesting success. We used a stage-specific matrix model to study the influence of vital rates, e.g., juvenile and adult annual survival, on population growth rate in the Mountain Plover at ...


Increased Abundance And First Breeding Record Of The Neotropic Cormorant (Phalacrocorax Brasilianus) On The Alluvial Plain Of Mississippi, Katie C. Hanson, Travis L. DeVault, Stephen J. Dinsmore 2010 United States Department of Agriculture

Increased Abundance And First Breeding Record Of The Neotropic Cormorant (Phalacrocorax Brasilianus) On The Alluvial Plain Of Mississippi, Katie C. Hanson, Travis L. Devault, Stephen J. Dinsmore

Natural Resource Ecology and Management Publications

Phalacrocorax brasilianus (Neotropic Cormorant) has been observed with increasing frequency in the alluvial plain (Delta region) of Mississippi. In the past 6 years, 22 individuals have been observed in 20 separate sightings during spring and summer. These sightings have occurred at breeding colonies of other colonial waterbirds and commercial aquaculture facilities of Ictalurus punctatus (Channel Catfi sh). Two sexually mature Neotropic Cormorants have been collected at a colonial waterbird breeding colony near the Mississippi River in the western Delta region among fl ocks of Phalacrocorax auritus (Double-crested Cormorants). Twice during the summer of 2008, confi rmed nesting of Neotropic Cormorants ...


A Planet By Any Other Name . . ., Kimberly Kessler Ferzan 2010 University of Pennsylvania Carey Law School

A Planet By Any Other Name . . ., Kimberly Kessler Ferzan

Faculty Scholarship at Penn Law

Scientific discoveries about Pluto and the rest of the universe led scientists to question Pluto’s status and ultimately to strip Pluto of its standing among planets. Neil deGrasse Tyson’s The Pluto Files masterfully weaves together the empirical, conceptual, and cultural questions surrounding Pluto’s demotion. The problem, for scientists and spectators alike, was this: there was no scientific definition of planet. This review systematizes the Pluto puzzle presented in the book and reveals its relevance for law. The questions presented by The Pluto Files – how man relates to the world, how man understands its conceptual categories, and how ...


A Virtual Visit To A Sustainable 2050, Robert Costanza 2010 Portland State University

A Virtual Visit To A Sustainable 2050, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

The article describes the situation in a virtual, sustainable world in 2050. Observations include stable global human population at 8 billion people, slightly decreasing material throughput of local and global economies with an average quality of life (QOL) index at 2% per year. It also notes the lower income gaps within and between countries, the return of global biodiversity and the problem with regards to the effects of climate change. It also adds the use of internal labor equivalent trading system (LETS).


Dimer Models For Knot Polynomials, Moshe Cohen 2010 Louisiana State University and Agricultural and Mechanical College

Dimer Models For Knot Polynomials, Moshe Cohen

LSU Doctoral Dissertations

A dimer model consists of all perfect matchings on a (bipartite) weighted signed graph, where the product of the signed weights of each perfect matching is summed to obtain an invariant. In this paper, the construction of such a graph from a knot diagram is given to obtain the Alexander polynomial. This is further extended to a more complicated graph to obtain the twisted Alexander polynomial, which involved "twisting" by a representation. The space of all representations of a given knot complement into the general linear group of a fixed size can be described by the same graph. This work ...


Women And Math Performance: The Effects Of Stereotype Threat, Math Identity, And Gender Identity, Felicia W. Chu 2010 Seton Hall University

Women And Math Performance: The Effects Of Stereotype Threat, Math Identity, And Gender Identity, Felicia W. Chu

Seton Hall University Dissertations and Theses (ETDs)

.


Test 1968: John Deere 8270r, Nebraska Tractor Test Laboratory 2010 University of Nebraska-Lincoln

Test 1968: John Deere 8270r, Nebraska Tractor Test Laboratory

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of ...


Test 1966: John Deere 8225r, Nebraska Tractor Test Laboratory 2010 University of Nebraska-Lincoln

Test 1966: John Deere 8225r, Nebraska Tractor Test Laboratory

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of ...


Assessing North American Influenza Dynamics With Hierarchical Spatio-Temporal Models, Jessica Anderson 2010 Utah State University

Assessing North American Influenza Dynamics With Hierarchical Spatio-Temporal Models, Jessica Anderson

All Graduate Plan B and other Reports

We present a general statistical modeling framework to characterize continental-level influenza dynamics in the United States for the purposes of examining state-level epidemiological sources and sinks. The methods we describe depend directly on state-level influenza data that are updated weekly and available on the internet. Advances in search engine query analysis have provided powerful new tools for collecting epidemiological data and, when used in conjunction with sophisticated statistical models, allow for the identification and quantification of the flow of influenza across the continental United States. Our proposed methods, when conditioned on this comprehensive search query product, can provide unprecedented scientific ...


Rare Earth Elements As An Investigative Tool Into The Source, Age, And Ecology Of Late Miocene To Late Pleistocene Fossils From The Tunica Hills, Louisiana, Lindsey Theresa Yann 2010 Louisiana State University and Agricultural and Mechanical College

Rare Earth Elements As An Investigative Tool Into The Source, Age, And Ecology Of Late Miocene To Late Pleistocene Fossils From The Tunica Hills, Louisiana, Lindsey Theresa Yann

LSU Master's Theses

Rare earth elements were investigated for their potential to determine provenance and depositional environments of vertebrate fossils found as float in creeks of the Tunica Hills region of Louisiana. Elemental analyses are used to test the hypotheses that fossils span multiple time periods, from late Miocene to late Pleistocene, and that elemental profiles can distinguish terrestrial depositional settings from possible estuarine deposits. In addition, the animals present were then used to test the hypothesis that Tunica Hills had late Pleistocene environmental conditions much like the modern Great Lakes region. This study is important because it provides new insight on the ...


Test 1982: New Holland Ts6030, Nebraska Tractor Test Laboratory 2010 University of Nebraska-Lincoln

Test 1982: New Holland Ts6030, Nebraska Tractor Test Laboratory

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of ...


Digital Commons powered by bepress