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Forest Health Impacts Of Bark Beetles, Dwarf Mistletoe, And Blister Rust In A Lake Tahoe Basin Mixed Conifer Stand, R. F. Walker, R. M. Fecko, W. B. Frederick, D. W. Johnson, W. W. Miller Dec 2007

Forest Health Impacts Of Bark Beetles, Dwarf Mistletoe, And Blister Rust In A Lake Tahoe Basin Mixed Conifer Stand, R. F. Walker, R. M. Fecko, W. B. Frederick, D. W. Johnson, W. W. Miller

Western North American Naturalist

Interactions between forest health variables and mensurational characteristics in an uneven-aged eastern Sierra Nevada mixed conifer stand were examined. The stand was located in the Lake Tahoe Basin on a site featuring a coarsely textured granitic soil and numerous rock outcrops. Its composition was dominated by California white fir (Abies concolor var. lowiana [Gord.] Lemm.), with Jeffrey pine (Pinus jeffreyi Grev. & Balf.) and sugar pine (Pinus lambertiana Dougl.) less prominent and incense-cedar (Libocedrus decurrens Torr.) and mountain alder (Alnus tenuifolia Nutt.) the most minor constituents. The majority of saplings and seedlings were white fir. …

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The Scotopic Visual Sensitivity Of Four Species Of Trout: A Comparative Study, Russell B. Rader, Timberley Belish, Michael K. Young, John Rothlisberger Dec 2007

The Scotopic Visual Sensitivity Of Four Species Of Trout: A Comparative Study, Russell B. Rader, Timberley Belish, Michael K. Young, John Rothlisberger

Western North American Naturalist

We compared the maximum scotopic visual sensitivity of 4 species of trout from twilight (mesotopic) to fully dark-adapted vision. Scotopic vision is the minimum number of photons to which a fully dark-adapted animal will show a behavioral response. A comparison of visual sensitivity under controlled laboratory conditions showed that brown trout (Salmo trutta) and brook trout (Salvelinus fontinalis) had maximum scotopic thresholds (1.1 × 10−4 µmol · m−2s−1, ~0.005 lux) 2 times lower than rainbow trout (Oncorhyncus mykiss) and Snake River cutthroat trout (Oncorhynchus clarki bouvieri), which …

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Incorporating Grain Size Effects In Taylor Crystal Plasticity, Bradley S. Fromm Dec 2007

Incorporating Grain Size Effects In Taylor Crystal Plasticity, Bradley S. Fromm

Theses and Dissertations

A method to incorporate grain size effects into crystal plasticity is presented. The classical Hall-Petch equation inaccurately predicts the macroscopic yield strength for materials with non-equiaxed grains or materials that contain unequal grain size distributions. These deficiencies can be overcome by incorporating both grain size and orientation characteristics into crystal plasticity theory. Homogenization relationships based on a viscoplastic Taylor-like approach are introduced along with a new function, the grain size and orientation distribution function (GSODF). Estimates of the GSODF for high purity α-titanium are recovered through orientation imaging microscopy coupled with the chord length distribution. A comparison between the new …

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Study Of The Reproducibility Of Proteomics Methods And Variability Of Fruit Fly Proteomes., Thomas Franklin Culwell Dec 2007

Study Of The Reproducibility Of Proteomics Methods And Variability Of Fruit Fly Proteomes., Thomas Franklin Culwell

Theses and Dissertations

The reliability of biomarker discovery by means of proteomics has been called into question. It was speculated that "background noise" variation resulting from differences in preparation and handling of samples and proteome dynamics may mask subtle, yet important, differences due to the biological condition. Little is understood about complex proteomes and their variability. A critical aspect of proteomic biomarker research that is largely unexplored is the comparative reproducibility of certain methods such as two-dimensional gel electrophoresis and liquid chromatography/mass spectrometry. In particular, with liquid chromatography/mass spectrometry, it is not known whether variability in peptide quantitation is dependent on any of …

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A Corpus-Based Approach To Determining Standard American English, Delys Ann Waite Snyder Dec 2007

A Corpus-Based Approach To Determining Standard American English, Delys Ann Waite Snyder

Theses and Dissertations

Many teachers, test designers, textbook writers, and instructional designers turn to books written by usage experts to determine what is correct standard written American English. Unfortunately, though, experts often disagree about what is correct and what is incorrect, and this disagreement can create problems with validity when people create and assess instruction about usage. One way to discover the rules of standard English usage is to describe what writers actually do in printed, edited English. Researchers can access large collections of standard English through digital text archives, which can be searched electronically. The text archives for this study were taken …

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Description Of The Trio/Upward Bound Students' Construction Of Vocations Using George Kelly's Rep Test Method, Maraia Sokia Weingarten Dec 2007

Description Of The Trio/Upward Bound Students' Construction Of Vocations Using George Kelly's Rep Test Method, Maraia Sokia Weingarten

Theses and Dissertations

The Information Age is revolutionizing the way we communicate, acquire knowledge, and perform work. Society is shifting from occupations rooted in industrial production to those associated with knowledge and information, requiring the development of new skills for changing occupations and updating old educational methods. Educators need to be aware of economic and social changes and have a vision for how to design career education to respond to those changes. Individuals must also be prepared to learn on their own as careers evolve and change. The training necessary to adapt to the changing career culture needs to be made available to …

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Registered Dietitian Dress And The Effect Of Dietitian Dress On Perceived Professionalism, Connie Lynn Packer Dec 2007

Registered Dietitian Dress And The Effect Of Dietitian Dress On Perceived Professionalism, Connie Lynn Packer

Theses and Dissertations

People use others' dress to make assumptions, including how they believe the wearer will behave. Observers then adjust their behavior in response to the anticipated behavior of the wearer. Physician or nurse dress affects the degree to which patients perceive the medical professional as confident, experienced, competent, mature, trustworthy, and professional. Dietitian dress has not been studied. Our purpose was to identify 1) the current level of formality of dress of registered dietitians (RD), 2) characteristics of dress codes, 3) the effect of RD dress on patient/client perceptions of professional traits, and 4) the level of formality at which an …

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Solid Phase Crystallization Of Vanadium Dioxide Thin Films And Characterization Through Scanning Electron Microscopy, Felipe Rivera Dec 2007

Solid Phase Crystallization Of Vanadium Dioxide Thin Films And Characterization Through Scanning Electron Microscopy, Felipe Rivera

Theses and Dissertations

Crystalline films of vanadium dioxide were obtained through thermal annealing of amorphous vanadium dioxide thin films sputtered on silicon dioxide. An annealing process was found that yielded polycrystalline vanadium dioxide thin films, semi-continuous thin films, and films of isolated single-crystal particles. Orientation Imaging Microscopy (OIM) was used to characterize and study the phase and the orientation of the vanadium dioxide crystals obtained, as well as to diferentiate them from other vanadium oxide stoichiometries that may have formed during the annealing process. There was no evidence of any other vanadium oxides present in the prepared samples. Indexing of the crystals for …

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Mayanwiki: An Online, Consensus-Based Linguistic Corpus Of The Mayan Hieroglyphs, Robbie A. Haertel Dec 2007

Mayanwiki: An Online, Consensus-Based Linguistic Corpus Of The Mayan Hieroglyphs, Robbie A. Haertel

Theses and Dissertations

The writing system used by the ancient Maya civilization has intrigued researchers and aficionados for centuries. Now that it has mostly been deciphered, the emphasis in the field of Mayan epigraphy has shifted to a study of the system of phonological, morphological, and grammatical rules that once governed the language that the hieroglyphs encode. One of the most important resources for linguistic study of this type is a comprehensive, electronic corpus of texts to investigate phraseology, frequency information, and collocations. Because Mayan linguistic epigraphy is in the early stages, a publicly available, editable corpus would be an invaluable resource in …

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Pioneers In Twentieth Century Mormon Media: Oral Histories Of Latter-Day Saint Electronic And Public Relations Professionals, Jonice L. Hubbard Dec 2007

Pioneers In Twentieth Century Mormon Media: Oral Histories Of Latter-Day Saint Electronic And Public Relations Professionals, Jonice L. Hubbard

Theses and Dissertations

The project consists of three parts: a summary of the research, a collection of sixteen oral histories of Latter-day Saint Electronic Media and Public Relations professionals who contributed to the development and growth of media in the Church of Jesus Christ of Latter-day Saints, and a one-hour documentary film, Pioneers in Mormon Media, which gives a brief history of the development of modern mass communications and its use by the Church. This qualitative study investigates who has been involved in Church media, what projects have been accomplished and provides some explanation as to why the Church uses media. The oral …

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Beneficial Fungal Interactions Resulting In Accelerated Germination Of Astragalus Utahensis, A Hard-Seeded Legume, Sean D. Eldredge Dec 2007

Beneficial Fungal Interactions Resulting In Accelerated Germination Of Astragalus Utahensis, A Hard-Seeded Legume, Sean D. Eldredge

Theses and Dissertations

Seed germination is pivotal in the life cycle of native plants in a restorative context because initiation of the metabolic processes critical to establishment is key to survival in such a competitive environment. Dormancy characteristics of some native plants including the subject species, Astragalus utahensis, have evolved mechanisms to control germination in order to maintain a seed bank and ensure germination at the right time under optimal conditions. In vitro germination studies confirm beneficial interactions between Alternaria and Aspergillus fungi and Astragalus utahensis seed. Inoculated seed trials (1.0 x 106 spores/mL) exhibited a highly significant difference in percent germination between …

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Byu Students' Beliefs About Language Learning And Communicative Language Teaching Activities, Sarah C. Bakker Dec 2007

Byu Students' Beliefs About Language Learning And Communicative Language Teaching Activities, Sarah C. Bakker

Theses and Dissertations

Learner beliefs, which contribute to attitude and motivation, may affect language learning. It is therefore valuable to investigate the malleability of learner beliefs, and to determine whether potentially detrimental beliefs can be ameliorated. This study examines how instruction of the principles of Second Language Acquisition (SLA) affects students' beliefs about classroom activities and their beliefs about language learning in general. The 68 first-year German students at Brigham Young University who participated in this study were asked to rate the effectiveness of three activities typical of communicative language teaching: Dialogue activities, Peer Interview activities, and Information-gap activities. They were also asked …

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Niche Separation Along Environmental Gradients As A Mechanism To Promote The Coexistence Of Native And Invasive Species, Edmund R. Priddis Dec 2007

Niche Separation Along Environmental Gradients As A Mechanism To Promote The Coexistence Of Native And Invasive Species, Edmund R. Priddis

Theses and Dissertations

Niche separation may be the key to promoting the long-term coexistence of introduced and native species. Physical alterations to the environment (habitat manipulation) or re-introducing native species to former habitats can exploit the maladapted traits of introduced species to create a refuge for native species. No two species have identical niches because evolutionary constraints differ between species with different evolutionary histories. Our objectives were to determine if cold temperatures could promote coexistence between native least chub and introduced western mosquitofish. We used individual scale and population scale experiments to test four hypotheses: 1) colder temperatures would reduce the aggressive behavior …

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One-Dimensional Radial Flow Turbomachinery Performance Modeling, Robert John Pelton Dec 2007

One-Dimensional Radial Flow Turbomachinery Performance Modeling, Robert John Pelton

Theses and Dissertations

The Two-Element In Series (TEIS) and Two-Zone models have been used successfully for over twenty years to model test data for radial flow compressors and pumps. The models can also be used to predict the performance of new machines provided that the model inputs can be accurately specified. Unfortunately, use of the TEIS and Two-Zone models as a predictive tool has been limited because an accurate and broadly applicable method of predicting the modeling parameters, etaA, etaB, chi and d2p does not exist. Empirical models have been developed to predict the TEIS and Two-Zone modeling parameters based on a large …

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The Church Of Jesus Christ Of Latter-Day Saints In National Periodicals: 1991-2000, Casey William Olson Nov 2007

The Church Of Jesus Christ Of Latter-Day Saints In National Periodicals: 1991-2000, Casey William Olson

Theses and Dissertations

From 1991 through 2000, The Church of Jesus Christ of Latter-day Saints experienced a greater volume of national periodical attention than ever before in its history. This thesis surveys what was written about the Church in national magazines during that time and provides analysis of the effect of those writings on the Church's public image. National periodicals may serve as an important gauge of the Church's public image because they address topics of national interest and also help to formulate public opinion on those topics. This study thus provides a basis for determining how the Church fared in terms of …

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An Evaluation Of A Low-Cost Uav Approach To Noxious Weed Mapping, Brandon Tyler Jones Nov 2007

An Evaluation Of A Low-Cost Uav Approach To Noxious Weed Mapping, Brandon Tyler Jones

Theses and Dissertations

Mapping their location and extent is a critical step in noxious weed management. One of the most common methods of mapping noxious weeds is to walk the perimeter of each patch with a handheld GPS receiver. This is the method used at Camp Williams, a National Guard Bureau training facility in Utah where this study was conducted. It was proposed that a low-cost Unmanned Aerial Vehicle (UAV) that made use of a hobbyist remote control airplane equipped with a Global Positioning System (GPS) receiver and digital camera could be used along with automated post-processing techniques to reduce the cost of …

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Low-Voltage Analog Cmos Architectures And Design Methods, Kent Downing Layton Nov 2007

Low-Voltage Analog Cmos Architectures And Design Methods, Kent Downing Layton

Theses and Dissertations

This dissertation develops design methods and architectures which allow analog circuits to operate at VT + 2Vds,sat, the minimum supply for CMOS circuits with all transistors in the active region where Vds,sat is the drain to source saturation voltage of a MOS transistor. Techniques which meet this criteria for rail-to-rail input stages, gain enhancement stages, and output stages are discussed and developed. These techniques are used to design four fully-differential rail-to-rail amplifiers. The highest gain is shown to be attained using a drain voltage equalization (DVE) or active-bootstrapping technique which produces more than 100dB of gain in a two stage …

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Dreamwork With Children: Perceptions And Practice Of School-Based Mental Health Professionals, Rosalia Rodriguez Huermann Nov 2007

Dreamwork With Children: Perceptions And Practice Of School-Based Mental Health Professionals, Rosalia Rodriguez Huermann

Theses and Dissertations

Forty nine public school mental health practitioners (i.e., school counselors, school psychologists, and school social workers) completed a survey about working with dreams when counseling students. Most practitioners in this sample reported having at least one student bring up dreams during counseling and spent some time in counseling working with students' dreams. Practitioners addressed dreams more frequently in situations where the student was having troubling dreams or nightmares, and/or was dealing with death and grief. They also acknowledged working with dreams with students who were diagnosed with Post Traumatic Stress Disorder, were emotionally disturbed, suffered from recurrent dreams, were depressed, …

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Shear Modulus Degradation Of Liquefying Sand: Quantification And Modeling, Peter A. Olsen Nov 2007

Shear Modulus Degradation Of Liquefying Sand: Quantification And Modeling, Peter A. Olsen

Theses and Dissertations

A major concern for geotechnical engineers is the ability to predict how a soil will react to large ground motions produced by earthquakes. Of all the different types of soil, liquefiable soils present some of the greatest challenges. The ability to quantify the degradation of a soil's shear modulus as it undergoes liquefaction would help engineers design more reliably and economically. This thesis uses ground motions recorded by an array of downhole accelerometers on Port Island, Japan, during the 1995 Kobe Earthquake, to quantify the shear modulus of sand as it liquefies. It has been shown that the shear modulus …

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Transient Molecular Dynamics Simulations Of Viscosity For Simple Fluids, Richard L. Rowley, Jason C. Thomas Nov 2007

Transient Molecular Dynamics Simulations Of Viscosity For Simple Fluids, Richard L. Rowley, Jason C. Thomas

Faculty Publications

A transient molecular dynamics (TMD) method has been developed for simulation of fluid viscosity. In this method a sinusoidal velocity profile is instantaneously overlaid onto equilibrated molecular velocities, and the subsequent decay of that velocity profile is observed. The viscosity is obtained by matching in a least-squares sense the analytical solution of the corresponding momentum transport boundary-value problem to the simulated decay of the initial velocity profile. The method was benchmarked by comparing results obtained from the TMD method for a Lennard-Jones fluid with those previously obtained using equilibrium molecular dynamics (EMD) simulations. Two different constitutive models were used in …

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Book Review:The Swiss And The Nazis: How The Alpine Republic Survived In The Shadow Of The Third Reich, Louis B. Kuppenheimer Nov 2007

Book Review:The Swiss And The Nazis: How The Alpine Republic Survived In The Shadow Of The Third Reich, Louis B. Kuppenheimer

Swiss American Historical Society Review

For hundreds of years Switzerland has been recognized as a nation committed to not being involved in military conflicts. However, in WWII it was confronted by the most serious and credible threat to its neutrality since the inception of the policy. To begin with, Switzerland's wartime population of 4,200,000 was outnumbered nearly eighteen to one by its most lethal contiguous neighbor, Germany. When Austria and Italy were thrown in, the ratio jumped to thirty to one. In addition, the Axis powers of Italy and Germany shared over seventy percent of Switzerland's border. And although her industrial production was of the …

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Polarization Rotation Correction In Radiometry: An Error Analysis, David G. Long, Derek Hudson, Jeffrey R. Piepmeier Nov 2007

Polarization Rotation Correction In Radiometry: An Error Analysis, David G. Long, Derek Hudson, Jeffrey R. Piepmeier

Faculty Publications

Yueh proposed a method of using the third Stokes parameter TU to correct brightness temperatures such as Tv and Th for polarization rotation. This paper presents an extended error analysis of the estimation of Tv , Th, and TQ equiv Tv - Th by Yueh's method. In order to carry out the analysis, we first develop a forward model of polarization rotation that accounts for the random nature of thermal radiation, receiver noise, and (to first order) calibration. Analytic formulas are then derived for the bias, standard deviation (STD), and root-mean-square error (RMSE) of estimated TQ, Tv , and Th, …

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The Effects Of Peer Praise Notes On Socially Withdrawn Adolescents: A Classroom Intervention, Julie Nelson, Natalie Webb, Paul Caldarella Nov 2007

The Effects Of Peer Praise Notes On Socially Withdrawn Adolescents: A Classroom Intervention, Julie Nelson, Natalie Webb, Paul Caldarella

Faculty Publications

Relationships with non-parental adults are vital assets for positive youth development (Scales, 2003). Studies of resilience among youth from at risk backgrounds alerted scholars to protective functions that can be fulfilled by relationships with non parental adults (Werner, 1995)

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School-Based Mentoring: An Effective Intervention With Students At Risk For Ebd, Paul Caldarella, Shauna Valentine, K. Richard Young, Michael Adams Nov 2007

School-Based Mentoring: An Effective Intervention With Students At Risk For Ebd, Paul Caldarella, Shauna Valentine, K. Richard Young, Michael Adams

Faculty Publications

Relationships with non-parental adults are vital assets for positive youth development (Scales, 2003). Studies of resilience among youth from at risk backgrounds alerted scholars to protective functions that can be fulfilled by relationships with non parental adults (Werner, 1995).

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Gender Differences And Similarities In The Work-Family Interface: The Importance Of Considering Family Life Stages, Giuseppe Martinengo Oct 2007

Gender Differences And Similarities In The Work-Family Interface: The Importance Of Considering Family Life Stages, Giuseppe Martinengo

Theses and Dissertations

This study focuses on the importance of considering the interaction between gender and family life stages to properly understand gender similarities and differences in the work and family interface. Data for this study come from the IBM 2004 Global Work and Life Issues Survey representing 79 countries (N=41,813). This study is a first step toward a better understanding of similarities and differences among male and female workers across the life course and it shows that work, family and life outcomes are similar across groups, independent of life stages or gender. Six family life stage groups were created: no children and …

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Looking On The Bright Side: The Role Of Identity Status And Gender On Positive Orientations During Emerging Adulthood, Laura M. Padilla-Walker, Carolyn Mcnamara Barry, Jason S. Carroll, Stephanie D. Madsen, Larry J. Nelson Oct 2007

Looking On The Bright Side: The Role Of Identity Status And Gender On Positive Orientations During Emerging Adulthood, Laura M. Padilla-Walker, Carolyn Mcnamara Barry, Jason S. Carroll, Stephanie D. Madsen, Larry J. Nelson

Faculty Publications

Emerging adulthood has been characterized as an age of possibilities that involves heightened identity exploration and risk-taking. Although some scholars have investigated the relation between identity status and risk behaviors in emerging adulthood, less attention has been paid to the relation between identity status and prosocial orientations. Thus, the current study examined how emerging adults’ engagement in positive behaviors (i.e., prosocial tendencies, internalization of values, religiosity) varied as a function of identity status and gender. Results indicated that emerging adults who were in identity diffusion reported fewer prosocial tendencies, lower scores on internalization of values and lower religiosity, but emerging …

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The Association Of Racial Attitudes And Spiritual Beliefs In Post-Apartheid South Africa, Timothy B. Smith, Christopher R. Stones, Christopher E. Peck, Anthony V. Naidoo Oct 2007

The Association Of Racial Attitudes And Spiritual Beliefs In Post-Apartheid South Africa, Timothy B. Smith, Christopher R. Stones, Christopher E. Peck, Anthony V. Naidoo

Faculty Publications

Previous research has investigated the complex association between religious beliefs and racism. Many studies have found that fundamentalist religious beliefs are positively associated with racial prejudice among European and European American populations. However, few studies have examined whether this association is found in other cultures or whether the association also characterizes spiritual beliefs. Data from 493 South African university students from three racial backgrounds revealed significant differences among the groups. A positive association between fundamentalism and racial prejudice was found among participants, but general spiritual beliefs were negatively associated with racist attitudes. The results emphasize the need to address contextual …

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Inter- And Intra-Subject Variability: A Palatometric Study, Marybeth Corey Sanders Oct 2007

Inter- And Intra-Subject Variability: A Palatometric Study, Marybeth Corey Sanders

Theses and Dissertations

Electropalatometry (EPM) has proven to be a useful clinical and research tool for measuring tongue-to-palate contact. The goal of this study was to determine whether the development of a database of standardized palatometric articulation files is feasible by examining the variability which exists within and between speakers. Twenty standard American English dialect speakers were fitted with palatometer pseudopalates. Test stimuli were VCV nonsense words using a schwa in the initial position, the 15 palatal consonants, and three corner vowels, /a/, /i/, /u/. From these palatometric recordings a variability index was created to examine intra- and interspeaker variability. Different aspects of …

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A Generalized Two-Dimensional Model To Reconstruct The Impact Phase In Automobile Collisions, Regis Agenor David Oct 2007

A Generalized Two-Dimensional Model To Reconstruct The Impact Phase In Automobile Collisions, Regis Agenor David

Theses and Dissertations

Automobile accident reconstruction has been facilitated by the development of computer based modules to allow evaluation of evidence gathered at the accident scenes. Although the computer modules are based in fundamental physical laws, an understanding of these laws by the user is required for proper application of the computer model in a given accident scenario. Vehicle collision analysis techniques generally separate the collision into three phases: pre-impact, impact, and post impact. The intent of the research is to provide a generalized model to reconstruct two dimensional impact problems in the area of accident reconstruction. There are currently two modeling techniques …

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Documentary Records Of The Prevention Of Schistosomiasis In China, Ka Wai Fan Oct 2007

Documentary Records Of The Prevention Of Schistosomiasis In China, Ka Wai Fan

Journal of East Asian Libraries

No abstract provided.

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