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Topology And Control Investigation For Low-Voltage High-Current Isolated Dc-Dc Converters, Hong Mao

Retrospective Theses and Dissertations

High conversion efficiency and fast transient response at high switching frequency are the two main challenges for low-voltage high-current DC-DC converters, which are the motivations of the dissertation work.

To reduce the switching power loss, soft switching is a desirable technique to keep power loss under control at high switching frequencies. A Duty-Cycle-Shift (DCS) concept is proposed for half-bridge DC-DC converters to reduce switching loss. The concept of this new control scheme is shifting one of the two symmetric PWM driving signals close to the other, such that ZVS can be achieved for the lagging switch due to the shortened …

Prescribed Fire Impacts To Amphibians And Reptiles In Shelterwood-Harvested Oak-Dominated Forests, Patrick D. Keyser, David J. Sausville, W. Mark Ford, Donald J. Schwab, Patrick H. Brose

Virginia Journal of Science

As part of a larger study examining the role of prescribed fire in regenerating upland oaks (Quercus spp.), seasonal prescribed burns (winter, spring, summer, and unburned control) were applied to first-stage shelterwood-harvested stands on Horsepen Wildlife Management Area in the Virginia Piedmont in 1995. Because fire impacts are poorly documented for herpetofaunal communities, we surveyed these stands in 1996 capturing 133 individuals of ten species during over 12,720 pitfall trapnights. We found no significant differences in relative abundance of Eastern Red-backed Salamanders (Plethodon cinereus) (P = 0.26), American Toads (Bufo americanus) (P = 0.93), …

Increasing The Angle Of Educational Reform In Pakistan: Through Professional Development, Nilofar Vazir, Alan Wheeler

Institute for Educational Development, Karachi

This paper documents the development of a “grassroots” teacher professional development model from Pakistan and region designed around three critical aspects: (a) the impact on classroom teaching and learning, (b) the provision for capacity building, and (c) a mechanism for ongoing support and sustainability. The development and evolution of the innovation is presented in terms of three stages designed to increase the angle of educational reform through total school improvement. The implications of the model as a promising prototype are discussed in relation to the wider professional development needs of teachers in the developing world.

Neutron Multiplicity Measurements Of Target/Blanket Materials, Denis Beller

Transmutation Sciences Physics (TRP)

To optimize the performance of accelerator-driven transmutation subcritical systems (ADS), engineers will need to design the system to operate with a neutron multiplication factor just below that of a critical, or self-sustaining, system. This design criterion requires particle transport codes that instill the highest level of confidence with minimal uncertainty, because larger uncertainties in the codes require larger safety margins in the design and result in a lower efficiency of the ADS transmuter. For current design efforts in the U.S., a Monte Carlo particle transport code MCNPX is used to model neutron production and transport for spallation neutron systems.

While …

Vemap Phase 2 Bioclimatic Database. I. Gridded Historical (20th Century) Climate For Modeling Ecosystem Dynamics Across The Conterminous Usa, T. G. F. Kittel, N. A. Rosenbloom, J. A. Royle, C. Daly, W. P. Gibson, H. H. Fisher, P. Thornton, D. N. Yates, C. Kaufman, R. Mckeown, D. Bachelet, D. S. Schimel, Steven W. Running, Vemap2 Participants

Ecosystem and Conservation Sciences Faculty Publications

Analysis and simulation of biospheric responses to historical forcing require surface climate data that capture those aspects of climate that control ecological processes, including key spatial gradients and modes of temporal variability. We developed a multivariate, gridded historical climate dataset for the conterminous USA as a common input database for the Vegetation/Ecosystem Modeling and Analysis Project (VEMAP), a biogeochemical and dynamic vegetation model intercomparison. The dataset covers the period 1895-1993 on a 0.5° latitude/longitude grid. Climate is represented at both monthly and daily timesteps. Variables are: precipitation, mininimum and maximum temperature, total incident solar radiation, daylight-period irradiance, vapor pressure, and …

Evolution Dynamics Of A Dense Frozen Rydberg Gas To Plasma, Wenhui Li, Michael W. Noel, Michael P. Robinson, Paul J. Tanner, Thomas F. Gallagher, Daniel Comparat, Bruno Laburthe Tolra, Nicolas Vanhaecke, Thibault Vogt, Nassim Zahzam, Pierre Pillet, Duncan A. Tate

Physics Faculty Research and Scholarship

Dense samples of cold Rydberg atoms have previously been observed to spontaneously evolve to a plasma, despite the fact that each atom may be bound by as much as 100 cm−1. Initially, ionization is caused by blackbody photoionization and Rydberg-Rydberg collisions. After the first electrons leave the interaction re- gion, the net positive charge traps subsequent electrons. As a result, rapid ionization starts to occur after 1 μs caused by electron-Rydberg collisions. The resulting cold plasma expands slowly and persists for tens of microseconds. While the initial report on this process identified the key issues described above, it failed to …

Fifteen Years Of Plant Community Dynamics During A Northwest Ohio Oak Savanna Restoration, Scott R. Abella, John F. Jaeger, Lawrence G. Brewer

Public Policy and Leadership Faculty Research

Midwest oak savanna communities are noted for their unusual plant assemblages, but these communities have been reduced by more than 98% because of changing land uses and conversion to closed-canopy forests. We initiated an ongoing 15-year experiment in 1988 to restore a 40-ha black oak (Quercus velutina) savanna by applying burn treatments that historically maintained this vegetation type. Groundlayer composition changed significantly for both the burn treatment and the control, with the burn treatment exhibiting slight increases in herbs such as wild lupine (Lupinus perennis) and hairy puccoon (Lithospermum caroliniense), both of which are species requiring greater insolation. Burn treatments …

Oliver Ranch Science School Complex & Wild Horse And Burro Facility: Quarterly Progress Report, Period Ending September 30, 2004, Margaret N. Rees

Oliver Ranch Project

Assist in project coordination between numerous stakeholders such as the Clark County School System, Desert Research Institute, Community College of Southern Nevada, UNR Cooperative Extension, Nevada State College, local museums, state parks, non-profit organizations, federal agencies, and the public to ensure appropriate educational curricular activities and venues are provided for in the conceptual design of the School and the Wild Horse and Burro facility where appropriate as well as assist in the NEPA process as needed. The activities will be conducted at least in part by university faculty, staff and students as part of the university’s research, teaching, and service …

The Mutamathil Type Style: Towards Free, Technology-Friendly, Arabetic Types, Saad D. Abulhab

Publications and Research

Efforts to adapt various Arabetic scripts to the machine are as old as the field of typography. But most of these efforts concentrated primarily on forcing the machine to duplicate the Arabetic handwritten forms. Others have practically advocated divorce from the calligraphic tradition rather than enrichment and reform. One reason why the few modern attempts to typographically solve the technology-induced Arabetic script problems had failed is that many typeforms (or many times just theoretical calligraphy style) was presented as replacement for the traditional ones rather than as optional working types. New “controversial” types should be made widely available for users …

Size Of Rve & Effect Of Morphology On Local Fields : A Statistical And Numerical Approach, Diwakar Anipindi

Electronic Theses and Dissertations

No abstract provided.

Petrography Of Lower Cretaceous Sandstones On Spitsbergen, Harmon D. Maher Jr., Troy Hays, Robert Duncan Shuster, Jeremy Mutrux

Geography and Geology Faculty Publications

The sandstone petrography of sample suites from four sites spanning the Rurikfjellet (Hauterivian) to Carolinefjellet (Aptian–Albian) formations in central Spitsbergen was investigated. The sandstones show a distinct stepwise shift in composition from quartz arenites to sublitharenites and lithic arenites, typically within the upper part of the Helvetiafjellet Formation. This shift is related to the introduction of 10 - 25 % (grain %) plagioclase grains and volcanic lithics, and a notable increase in basement and sedimentary lithics. Quartz grain character also changes, and grain shapes become more varied. The shift is also associated with the transgressive arrival of marine sediments in …

Ac Frequency Dependence Of Electroluminescent Zns Phosphor Panel Color, Farrah Shantell Boggess-Machado

Theses, Dissertations and Capstones

In this study, electroluminescent panels manufactured by Meadow River Enterprises were used to study the AC frequency dependence of their color. A project was developed to acquire their emittance color at various frequencies. Three frequencies were selected for the investigation. Data, obtained by measuring the spectrum at a constant excitation frequency, were taken for each of the three standard frequencies: 200 Hz, 1500 Hz, and 20 kHz. In general the higher the frequency, the bluer the emittance color of the panel. The lower the frequency, the more green the panel became. An explanation for this phenomenon, the frequency dependence of …

Forecasting The Onset Of Cloud-Ground Lightning Using S-Pol And Nldn Data, Kartik Ramakrishnan

Electronic Theses and Dissertations

The maximum number of thunderstorms in the United States occur in Central Florida. The cloud-ground lightning from these storms is responsible for extensive damage to life and property. The lightning from these storms is also responsible for delays and cancellations of space shuttle launch attempts at the Kennedy Space Center (KSC) and the 45th Space Wing unmanned launches at Cape Canaveral launch facilities. For these and other reasons accurate forecasting of cloud-ground lightning is of crucial importance. The second phase of NASA's Tropical Rainfall Measuring Mission Texas and Florida Underflights project (TEFLUN-B) was conducted between 1st August and 30th September, …

George Liska's Realist Alliance Theory, And The Transformation Of Nato, Sergey Kireyev

Electronic Theses and Dissertations

In many aspects, political theory forms a subjective structure of this abstract science. Perhaps, it is due to the fact that unlike natural sciences or mathematics, social sciences often lack the privilege of testing the theories in absolute and unadulterated conditions. Nonetheless, such nature of the science allows for a certain degree of flexibility, when applying political theories to real-world phenomena. Alliances and coalitions in international relations form the backbone of the theory, concerning IR scholars with two main questions: Why do alliances and coalitions form? And, what keeps alliances and coalitions together? As the core of my research, I …

Measuring The Effect Of Erratic Demandon Simulated Multi-Channel Manuf, Nancy Kohan

Electronic Theses and Dissertations

To handle uncertainties and variabilities in production demands, many manufacturing companies have adopted different strategies, such as varying quoted lead time, rejecting orders, increasing stock or inventory levels, and implementing volume flexibility. Make-to-stock (MTS) systems are designed to offer zero lead time by providing an inventory buffer for the organizations, but they are costly and involve risks such as obsolescence and wasted expenditures. The main concern of make-to-order (MTO) systems is eliminating inventories and reducing the non-value-added processes and wastes; however, these systems are based on the assumption that the manufacturing environments and customers' demand are deterministic. Research shows that …

Evaluation Of The Photo-Induced Structural Mechanisms In Chalcogenide, Cedric Lopez

Electronic Theses and Dissertations

Chalcogenide glasses and their use in a wide range of optical, electronic and memory applications, has created a need for a more thorough understanding of material property variation as a function of composition and in geometries representative of actual devices. This study evaluates compositional dependencies and photo-induced structural mechanisms in As-S-Se chalcogenide glasses. An effective fabrication method for the reproducible processing of bulk chalcogenide materials has been demonstrated and an array of tools developed, for the systematic characterization of the resulting material's physical and optical properties. The influence of compositional variation on the physical properties of 13 glasses within the …

The Relationship Of High School Mathematics Standard Test Scores And Illustration And Design Technology Courses, Richard R. Dyer

OTS Master's Level Projects & Papers

To guide the solution of this problem, the following hypotheses were developed: 1. Students who have taken illustration and design technology courses test better on their mathematics SOL tests than students that did not take technology courses; 2. Students who have not passed the mathematics SOL tests will do better on their retake examinations if they take an illustration and design course.

Does Excessive Absence From Class Lead To Lower Levels Of Academic Achievement, Janet L. Faison

OTS Master's Level Projects & Papers

Based on this problem, the following hypothesis has been proposed: 1. Students who have higher records of absenteeism (absent four times or more during a given semester) will have lower academic achievement levels (GPA) while attending community college.

Determining If Students At Northumberland High School Who Choose Ged Or Other Alternative Programs Are Successfully Prepared For Employment, Sandra Green

OTS Master's Level Projects & Papers

The following goals were established to guide this research: 1. Identify reasons students choose other programs to regular high school education; 2. Investigate programs that are available for students as alternatives to high school graduation; 3. Determine if assistance is being offered within the high school before students dropout of school; 4. Assess if students are properly prepared for work opportunities through investigating alternative education programs.

Determination Of Why Students Enrolled In Bluefield Regional Medical Center School Of Medical Technology Cannot Receive Government Financial Assistance, James E. Gibberson

OTS Master's Level Projects & Papers

The goals established to guide this study were as follows: 1. Determine why students cannot receive government financial assistance while performing their clinical training at Bluefield Regional Medical Center Laboratory; 2. Determine other means in which students may obtain financial assistance in order to pay for their clinical education at Bluefield Regional Medical Center; 3. Determine how can the institutions, Bluefield Regional Medical Center, Bluefield State College and Bluefield College, work together to form a system of financial assistance for students if government financial assistance is not available.

The Equipment Needs Of The Standards For Technological Literacy, Julian B. Duffey

OTS Master's Level Projects & Papers

These goals were analyzed to produce a standard equipment list for CATTS to recommend for implementation in participating states. It sought to: 1. Determine the equipment needs for elementary education programs implementing the Standards for Technological Literacy; 2. Determine the equipment needs for middle school education programs implementing the Standards for Technological Literacy; 3. Determine the equipment needs for high school education programs implementing the Standard for Technological Literacy.

The Success Rate Of Military Students In The Armed Services Vocational Aptitude Battery Preparation Class, Margaret A. Russo

OTS Master's Level Projects & Papers

To determine the solution to this problem, the following hypothesis was established: 1. Military students who had taken the two week, 54-hour ASVAB Preparation Class had a better rate of success than those who exceeded the two week 54-hour class and finished using the self-paced format.

Implementation Of Standards Of Technological Literacy, Scott A. Sonier

OTS Master's Level Projects & Papers

This descriptive research was driven by the following questions: 1) What is the level of overall implementation of the Standards for Technological Literacy? 2) What is the level of implementation for each of the Standards for Technological Literacy? 3) In what time frame do respondents expect their programs will have the Standards of Technological Literacy fully implemented? 4) Is there formal assessment supporting the Standards for Technological Literacy?

Chemical Vapor Deposited Diamond Films For Self-Referencing Fiber Optic Raman Probes [Erratum], Sacharia Albin, Jainli Zheng, Bing Xiao, John B. Cooper, Robert B. Jeffers, Sonia Antony

Chemistry & Biochemistry Faculty Publications

No abstract provided.

On The Ecological Status Of The Concept "Boundary Conditions" - A Few Methodological Remarks, Lubomira Burchardt, Krzystof Lastowski, Harold G. Marshall

Biological Sciences Faculty Publications

Plant and animal populations are frequently found in habitats where the environmental conditions are considered extreme or challenging for life form to exist. These conditions may be classified as either: (1) Supreme: a situation characteristic of degradation conditions where only a few species live under stress, and (2) Extra-ordinary: habitats that provide high biodiversity that are under stress conditions. Due to the differences in what we consider extreme conditions, it is necessary to distinguish between these two categories, because they are not comparable. Our presentation will include examples of these two extreme environmental categories.

State Of Utah V. David Roger Markland : Reply Brief Of Petitioner, Utah Supreme Court

Utah Supreme Court Briefs (2000–2020)

ON WRIT OF CERTIORARI TO THE UTAH COURT OF APPEALS

B.A.M. Development, A Utah Limited Liability Company V. Salt Lake County, A Body Corporate And Politic Of The State Of Utah : Amicus Curiae Brief, Utah Supreme Court

Utah Supreme Court Briefs (2000–2020)

THE UTAH STATE PROPERTY RIGHTS OMBUDSMAN IN SUPPORT OF THE POSITION OF THE CROSS-PETITIONER BAM DEVELOPMENT, LLC ON WRIT OF CERTIORARI TO THE UTAH COURT OF APPEALS

Scholarship, Pepperdine University, And The Legacy Of Churches Of Christ, Richard T. Hughes, Thomas H. Olbricht

Center for Faith and Learning Publications

We hope that this small book will help Pepperdine faculty and staff members understand more about the specific Christian tradition to which Pepperdine is related-the Churches of Christ-and how that tradition can fruitfully interact with and even sustain the task of Christian higher education in the context of this institution.

Advances And Applications Of Dezert-Smarandache Theory (Dsmt), Vol. 1, Florentin Smarandache, Jean Dezert

Branch Mathematics and Statistics Faculty and Staff Publications

The Dezert-Smarandache Theory (DSmT) of plausible and paradoxical reasoning is a natural extension of the classical Dempster-Shafer Theory (DST) but includes fundamental differences with the DST. DSmT allows to formally combine any types of independent sources of information represented in term of belief functions, but is mainly focused on the fusion of uncertain, highly conflicting and imprecise quantitative or qualitative sources of evidence. DSmT is able to solve complex, static or dynamic fusion problems beyond the limits of the DST framework, especially when conflicts between sources become large and when the refinement of the frame of the problem under consideration …

Fuzzy Relational Maps And Neutrosophic Relational Maps, Florentin Smarandache, W.B. Vasantha Kandasamy

Branch Mathematics and Statistics Faculty and Staff Publications

The aim of this book is two fold. At the outset the book gives most of the available literature about Fuzzy Relational Equations (FREs) and its properties for there is no book that solely caters to FREs and its applications. Though we have a comprehensive bibliography, we do not promise to give all the possible available literature about FRE and its applications. We have given only those papers which we could access and which interested us specially. We have taken those papers which in our opinion could be transformed for neutrosophic study. The second importance of this book is that …