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2006

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The Oldest Well, Saul Benjamin Becker Jan 2006

The Oldest Well, Saul Benjamin Becker

Theses and Dissertations

This body of work, representing the past two years, is focused on the idea of the composite landscape. This reconfiguring of the elements from the external world combined with invented places is a way for me to articulate the subtle transactions between the interior psyche and the external world. The way this new conglomerate space is represented is a result of my inquiry into the relationship between nature, culture, and the sublime. The place where the private acts of the studio meet the shared exterior world is where I find my intellect, fantasy, and sense of reality collaborating in chorus.

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Silicon Oxide Nanoparticles Reveal The Origin Of Silicate Grains In Circumstellar Environments, Peneé Armaize Clayborne Jan 2006

Silicon Oxide Nanoparticles Reveal The Origin Of Silicate Grains In Circumstellar Environments, Peneé Armaize Clayborne

Theses and Dissertations

The processes leading to the widespread presence of crystalline silicates throughout the galaxy and the origin of silicon nanoparticles thought to be responsible for the observed extended red emission in diffuse galactic background are still far from being understood. One of the most abundant oxygen bearing species in molecular astronomical regions is SiO. It has been conjectured that silicate formation probably proceeds via the agglomeration of these molecular species; however there are no studies to reveal the microscopic mechanism. We have used a synergistic approach combining experiments in molecular beams and first principles theoretical calculation to demonstrate that the passage …

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Grobner Bases And Ideals Of Points, Eun R. Chang Jan 2006

Grobner Bases And Ideals Of Points, Eun R. Chang

Theses and Dissertations

The main point of this thesis is an introduction to the theory of Grobner bases. The concept of Grobner basis and construction of the Grobner basis by Buchberger's Algorithm, in which the notion of S-polynomials is introduced, and a few modified or improved versions of Grobner basis algorithm are reviewed in this paper. In Chapter 1, we have a review of ideals, the definitions and types of monomial ordering, the multivariate polynomial division algorithm and its examples. After ascertaining the monomial ordering on multivariate polynomials, we establish a leading term of a polynomial.In Chapter 2, after defining Grobner bases, we …

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A Longitudinal Investigation Of Cognitive Predictors Of Self-Care Behaviors In Youth With Type I Diabetes, Michelle Marie Greene Jan 2006

A Longitudinal Investigation Of Cognitive Predictors Of Self-Care Behaviors In Youth With Type I Diabetes, Michelle Marie Greene

Theses and Dissertations

Cross-sectional research of youth with type I diabetes has demonstrated that rote and working memory predict blood glucose monitoring (BGM) and carbohydrate consumption, respectively; however, to date, no longitudinal follow-up studies exist. Rote and working memory subtests from well-standardized memory measures, along with a problem-solving and executive functioning measures were administered to 118 youth with type I diabetes, aged 9-16 in two waves of data collection (mean interval = 2.07 years). Diabetes care behaviors were assessed through the 24-hour Diabetes Interview. This study was the first to document longitudinal prediction of BGM by rote memory and fat consumption by working …

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How Promotions Effect Consumer Purchases, Justin D. White Jan 2006

How Promotions Effect Consumer Purchases, Justin D. White

Theses and Dissertations

Rational choice theory provides a blueprint for predicting individual behavior under the assumption that objectives and decisions are rationally identified and executed. Under certain conditions, actions reveal preferences and the ability to observe these preferences allows for the possibility to study the effects of subtle changes in individual constraints such as price and wealth affect preferences. For instance, recent work by Eckel and Grossman (2003), Davis, Millner and Reilly (2003), and Davis and Millner (2004) observe a preference for matching promotions over coupon rebates even when the two promotions types are strictly equivalent. An important question remaining is whether this …

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Traits Of Writing, Traits Of Art, Michelle Ciancarelli Becker Jan 2006

Traits Of Writing, Traits Of Art, Michelle Ciancarelli Becker

Theses and Dissertations

A study was conducted of Introductory Art students to find if the six traits of writing as written by Spandel/Stiggins (1997) would have influence over a narrative painting when combined with the six traits of painting. Inconclusive findings were reported. Data difference between the treated and untreated class was less than one point. More research needs to be conducted to study transfer of knowledge from verbal to visual as well as from one curriculum to another with both curriculums teaching same material.

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A Gis And Remote Sensing Based Analysis Of Impervious Surface Influences On Bald Eagle (Haliaeetus Leucocephalus) Nest Presence In The Virginia Portion Of The Chesapeake Bay, Jennifer M. Ciminelli Jan 2006

A Gis And Remote Sensing Based Analysis Of Impervious Surface Influences On Bald Eagle (Haliaeetus Leucocephalus) Nest Presence In The Virginia Portion Of The Chesapeake Bay, Jennifer M. Ciminelli

Theses and Dissertations

GIS (Geographic Information Systems) and remote sensing techniques were used to predict relationships between bald eagle nest presences and land type, distance to land type and impervious surface cover area. Data plots revealed bald eagle nest presence decreases in response to an increase in area of bareland; increases with an increase in area of forested land; decreases with an increase in distance (m) to shoreline, and decreases in response to an increase in area of impervious surfaces. Logistic regression models identified impervious surfaces as an indicator for bald eagle nest presence (P 24% as unsuitable. Unsuitable area covered 17.82% of …

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Photochemical Applications To The Study Of Complexity Phospholipid Bilayer Environments, Christopher John Wohl Jr. Jan 2006

Photochemical Applications To The Study Of Complexity Phospholipid Bilayer Environments, Christopher John Wohl Jr.

Theses and Dissertations

The physical and biophysical properties of a biological membrane model, phosphatidylcholine bilayers, were investigated using novel spiropyran/merocyanine molecular probes. The femtosecond to second dynamics of this system's photochemistry enabled bilayer viscosity and free volume to be studied over a broad time scale. Spiropyrans/merocyanines with different polarity were synthesized by changing the substitution of the indole moiety enabling determination of the trans-membrane properties of the bilayer. In addition, transient grating spectroscopy was used to study thermal energy transfer in phospholipid bilayers on a picosecond time scale.Femtosecond transient absorption spectroscopy was used to study the photo-induced spiropyran ring-opening and isomerization reactions that …

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Statistical Methods And Experimental Design For Inference Regarding Dose And/Or Interaction Thresholds Along A Fixed-Ratio Ray, Sharon Dziuba Yeatts Jan 2006

Statistical Methods And Experimental Design For Inference Regarding Dose And/Or Interaction Thresholds Along A Fixed-Ratio Ray, Sharon Dziuba Yeatts

Theses and Dissertations

An alternative to the full factorial design, the ray design is appropriate for investigating a mixture of c chemicals, which are present according to a fixed mixing ratio, called the mixture ray. Using single chemical and mixture ray data, we can investigate interaction among the chemicals in a particular mixture. Statistical models have been used to describe the dose-response relationship of the single agents and the mixture; additivity is tested through the significance of model parameters associated with the coincidence of the additivity and mixture models.It is often assumed that a chemical or mixture must be administered above an unknown …

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A Normal-Mixture Model With Random-Effects For Rr-Interval Data, Jessica Mckinney Ketchum Jan 2006

A Normal-Mixture Model With Random-Effects For Rr-Interval Data, Jessica Mckinney Ketchum

Theses and Dissertations

In many applications of random-effects models to longitudinal data, such as heart rate variability (HRV) data, a normal-mixture distribution seems to be more appropriate than the normal distribution assumption. While the random-effects methodology is well developed for several distributions in the exponential family, the case of the normal-mixture has not been dealt with adequately in the literature. The models and the estimation methods that have been proposed in the past assume the conditional model (fixing the random-effects) to be normal and allow a mixture distribution for the random effects (Xu and Hedeker, 2001, Xu, 1995). The methods proposed in this …

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The Effect Of Stationary Uv Excitation On The Optical Behavior Of Electrochemically Self-Assembled Semiconductor Nanowires, Rajesh A. Katkar Jan 2006

The Effect Of Stationary Uv Excitation On The Optical Behavior Of Electrochemically Self-Assembled Semiconductor Nanowires, Rajesh A. Katkar

Theses and Dissertations

In this work, we investigate the optical response of the semiconductor quantum wire array when excited by stationary UV light. The array is synthesized by selectively electro-depositing the semiconductor material in electrochemically self-assembled porous alumina templates. Our studies are based on the optical behavioral changes in CdS, ZnO, ZnSe and CdSe quantum wires of 50-, 25- and 10-nm diameters. We use a set of generalized Bloch equations to solve the interband polarization function of the semiconductors derived within the Hartree-Fock approximation, and theoretically model the UV excitation effect on the quantum wires. The solutions which consider the effects of screening, …

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A Prelude To A Third Dimension Of The Periodic Table: Superatoms Of Aluminum Iodide Clusters, Naiche Owen Jones Jan 2006

A Prelude To A Third Dimension Of The Periodic Table: Superatoms Of Aluminum Iodide Clusters, Naiche Owen Jones

Theses and Dissertations

Calculations have been carried out to investigate the stability and electronic structure of aluminum iodide clusters using first principles gradient-corrected density functional theory. Analysis of A113Ix-, A114Ix-, and A17I- clusters reveals that their stability is governed by the geometrically unperturbed A113-, A1142+, and A17+ units, respectively, that are demonstrated to constitute the compact cores of the clusters upon significant iodine content. The compact, icosahedral A113, icosahedral-like A1 14, and capped square bi-pyramid A17 superatom structures of the stable aluminum cores have an analogous electronic configuration to that of halogen, alkaline-earth, and alkaline atoms, respectively. Novel chemistry is demonstrated in superatoms, …

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Synthesis Of Novel Antimycobacterials And A Fluorescent Sensor For Simple Carbohydrates, Brian Thomas Walker Jan 2006

Synthesis Of Novel Antimycobacterials And A Fluorescent Sensor For Simple Carbohydrates, Brian Thomas Walker

Theses and Dissertations

Cell surface carbohydrates play an important role in a wide variety of biological processes such as inflammation, tumor metastasis, and viral and bacterial infection. The goal of our research has been two-fold. The first objective was the synthesis of antimycobacterial compounds. A mannose containing tetrasaccharide from the mannan core of lipoarabinomannan (LAM) of Mycobacterium tuberculosis has been synthesized using α-D-methylmannopyranoside as starting material and Koeings-Knorr reactions to couple saccharides. The synthesis was completed in nine steps and in 14% total yield. This compound should be useful in competitive inhibition studies with macrophages or as an immunological marker. We have successfully …

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Journaling For Critical Thinking, Paul E. Terrell Jr. Jan 2006

Journaling For Critical Thinking, Paul E. Terrell Jr.

Theses and Dissertations

This thesis describes a pretest - posttest study to increase the effectiveness of art journals at the high school level. The targeted population consisted of students in the ninth through twelfth grades in a middle class community, located in central Virginia. The visual art students were involved in the journaling (art workbook, sketchbook) process as a part of their curriculum. Following a pretest students were surveyed and adjustments were made from their input to make the art journals more effective. Often students were not picking up instructional cues introduced through demonstrations and art history integrated into the class structure. The …

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Membership Functions For A Fuzzy Relational Database: A Comparison Of The Direct Rating And New Random Proportional Methods, Shweta Sanghi Jan 2006

Membership Functions For A Fuzzy Relational Database: A Comparison Of The Direct Rating And New Random Proportional Methods, Shweta Sanghi

Theses and Dissertations

Fuzzy relational databases deal with imprecise data or fuzzy information in a relational database. The purpose of this fuzzy database implementation is to retrieve images by using fuzzy queries whose common-language descriptions are defined by the consensus of a particular user community. The fuzzy set, which is presentation of fuzzy attribute values of the images, is determined through membership function. This paper compares two methods of constructing membership functions, the Direct Rating and New Random Proportional, to determine which method gives maximum users satisfaction with minimum feedback from the community. The statistical analysis of results suggests the use of Direct …

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Meta-Analysis Of Open Vs Closed Surgery Of Mandibular Condyle Fractures, Marcy Lauren Nussbaum Jan 2006

Meta-Analysis Of Open Vs Closed Surgery Of Mandibular Condyle Fractures, Marcy Lauren Nussbaum

Theses and Dissertations

A review of the literature reveals a difference of opinion regarding whether open or closed reduction of condylar fractures produces the best results. It would be beneficial to critically analyze past studies that have directly compared the two methods in an attempt to answer this question. A Medline search for articles using the key words 'mandibular condyle fractures' and 'mandibular condyle fractures surgery' was performed. The articles chosen for the meta-analysis contained data on at least one of the following: postoperative maximum mouth opening, lateral excursion, protrusion, deviation on opening, asymmetry, and joint pain or muscle pain. Several common statistical …

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Quantifying The Effects Of Correlated Covariates On Variable Importance Estimates From Random Forests, Ryan Vincent Kimes Jan 2006

Quantifying The Effects Of Correlated Covariates On Variable Importance Estimates From Random Forests, Ryan Vincent Kimes

Theses and Dissertations

Recent advances in computing technology have lead to the development of algorithmic modeling techniques. These methods can be used to analyze data which are difficult to analyze using traditional statistical models. This study examined the effectiveness of variable importance estimates from the random forest algorithm in identifying the true predictor among a large number of candidate predictors. A simulation study was conducted using twenty different levels of association among the independent variables and seven different levels of association between the true predictor and the response. We conclude that the random forest method is an effective classification tool when the goals …

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Isolation Of Legionella Pneumophila From Well-Maintained Emergency Showers And Eyewash Stations, Jessica Mae Myers Jan 2006

Isolation Of Legionella Pneumophila From Well-Maintained Emergency Showers And Eyewash Stations, Jessica Mae Myers

Theses and Dissertations

Legionella pneumophila is a gram-negative bacterium responsible for Legionnaire's disease, and is commonly transmitted via aerosolized water. Legionella colonization of emergency eyewash and shower stations may pose an exposure hazard to users of these stations. There is little information about the role of these stations as significant reservoirs for Legionella. Samples were collected from 67 stations in an industrial facility. At the time of this study, the stations within this facility were under a routine maintenance program that included at least monthly flushing. This study also included the analysis for other bacterial organisms to determine an association between the presence …

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Raubeaux Scientician, Joe W. Grant Iii Jan 2006

Raubeaux Scientician, Joe W. Grant Iii

Theses and Dissertations

The works contained in "Raubeaux Scientician" are about a triadic relationship between people, science, and art. The obsessions, of individuals and the apparent change brought about by their physical presence guide my artistic research. I am awestruck at the capabilities of the individual to overcome conventional thought and through creative action yield a new vision. Some of the people I am fascinated by put forth theories and inventions that continue to affect myriad aspects of our world today. Among those at the forefront are, Robert Oppenheimer, and Edward Teller. Their contributions to science and mathematics remain almost unmatched. These and …

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Bayesian Analysis, Endogenous Data,And Convergence Of Beliefs, Andrew T. Foerster Jan 2006

Bayesian Analysis, Endogenous Data,And Convergence Of Beliefs, Andrew T. Foerster

Theses and Dissertations

Problems in statistical analysis, economics, and many other disciplines often involve a trade-off between rewards and additional information that could yield higher future rewards. This thesis investigates such a trade-off, using a class of problems known as bandit problems. In these problems, a reward-seeking agent makes decisions based upon his beliefs about a parameter that controls rewards. While some choices may generate higher short-term rewards, other choices may provide information that allows the agent to learn about the parameter, thereby potentially increasing future rewards. Learning occurs if the agent's subjective beliefs about the parameter converge over time to the parameter's …

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Relationships Among Stress, Blood Pressure, And Heart Rate Variability In Meditators, Sangthong Terathongkum Jan 2006

Relationships Among Stress, Blood Pressure, And Heart Rate Variability In Meditators, Sangthong Terathongkum

Theses and Dissertations

PROBLEM STATEMENT: Growing evidence indicates that psychological stress contributes to cardiovascular diseases through complex neuroendocrine mechanisms. Psychological stress leads to several physiological responses including increased heart rate (HR) and blood pressure (BP) as well as decreased heart rate variability (HRV) through alterations in the autonomic nervous system (ANS), specifically increased sympathetic nervous system (SNS) activity and decreased parasympathetic nervous system (PNS) activity. Meditation is thought to induce an innate relaxation response leading to reduced psychological stress. Findings from past studies have provided inconclusive evidence regarding the direction and strength of relationships among stress, BP, HRV, and meditation practice. PROCEDURES: A …

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The Impact Of No Child Left Behind On Charter School Legislation And Practices - Policy Implications, Joice Eaddy Conyers Jan 2006

The Impact Of No Child Left Behind On Charter School Legislation And Practices - Policy Implications, Joice Eaddy Conyers

Theses and Dissertations

The charter school movement is considered one of the fastest growing education reform efforts in the United States today, serving over 1 million children nationwide. The demand to improve the quality of education in the United States has been paramount over the last twenty years.In December 2001, Congress approved a reauthorization of the Elementary and Secondary Education Act (ESEA) and renamed it the No Child Left Behind Act of 2001 (NCLB), P.L. 107-ll0, H.R. 1. Although ESEA was enacted in 1964 by President Lyndon Johnson to supplement state and local efforts to provide all children with high-quality education, NCLB has …

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Design And Analysis Methods For Cluster Randomized Trials With Pair-Matching On Baseline Outcome: Reduction Of Treatment Effect Variance, Misook Park Jan 2006

Design And Analysis Methods For Cluster Randomized Trials With Pair-Matching On Baseline Outcome: Reduction Of Treatment Effect Variance, Misook Park

Theses and Dissertations

Cluster randomized trials (CRT) are comparative studies designed to evaluate interventions where the unit of analysis and randomization is the cluster but the unit of observation is individuals within clusters. Typically such designs involve a limited number of clusters and thus the variation between clusters is left uncontrolled. Experimental designs and analysis strategies that minimize this variance are required. In this work we focus on the CRT with pre-post intervention measures. By incorporating the baseline measure into the analysis, we can effectively reduce the variance of the treatment effect. Well known methods such as adjustment for baseline as a covariate …

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Improving Student Art Vocabulary Retention, Michelle Bena Mckenna Jan 2006

Improving Student Art Vocabulary Retention, Michelle Bena Mckenna

Theses and Dissertations

The purpose of this investigation was to research vocabulary strategies that could help improve student art vocabulary retention. The subjects were five intact 3rd grade classes at a culturally diverse elementary school outside of Washington, DC. The vocabulary strategies, concept wheel and semantic mapping, were modified and incorporated into a string printmaking unit for two of the five classes. The remaining three classes were taught the same printmaking unit, with the exclusion of the modified vocabulary activities. The results of a labeling assessment given to each class on three separate occasions indicate that the incorporation of vocabulary activities does help …

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Assessing, Modifying, And Combining Data Fields From The Virginia Office Of The Chief Medical Examiner (Ocme) Dataset And The Virginia Department Of Forensic Science (Dfs) Datasets In Order To Compare Concentrations Of Selected Drugs, Amy Elizabeth Herrin Jan 2006

Assessing, Modifying, And Combining Data Fields From The Virginia Office Of The Chief Medical Examiner (Ocme) Dataset And The Virginia Department Of Forensic Science (Dfs) Datasets In Order To Compare Concentrations Of Selected Drugs, Amy Elizabeth Herrin

Theses and Dissertations

The Medical Examiner of Virginia (ME) dataset and the Virginia Department of Forensic Science Driving Under the Influence of Drugs (DUI) datasets were used to determine whether people have the potential to develop tolerances to diphenhydramine, cocaine, oxycodone, hydrocodone, methadone, and morphine. These datasets included the years 2000-2004 and were used to compare the concentrations of these six drugs between people who died from a drug-related cause of death (of the drug of interest) and people who were pulled over for driving under the influence. Three drug pattern groups were created to divide each of the six drug-specific datasets in …

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Spin Polarized Transport In Nanoscale Devices, Sandipan Pramanik Jan 2006

Spin Polarized Transport In Nanoscale Devices, Sandipan Pramanik

Theses and Dissertations

The ultimate goal in the rapidly burgeoning field of spintronics is to realize semiconductor-based devices that utilize the spin degree of freedom of a single charge carrier (electron or hole) or an ensemble of such carriers to achieve novel and/or enhanced device functionalities such as spin based light emitting devices, spin transistors and femto-Tesla magnetic field sensors. These devices share a common feature: they all rely on controlled transport of spins in semiconductors. A prototypical spintronic device has a transistor-like configuration in which a semiconducting channel is sandwiched between two contacts (source and drain) with a gate electrode sitting on …

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A Comparison For Longitudinal Data Missing Due To Truncation, Rong Liu Jan 2006

A Comparison For Longitudinal Data Missing Due To Truncation, Rong Liu

Theses and Dissertations

Many longitudinal clinical studies suffer from patient dropout. Often the dropout is nonignorable and the missing mechanism needs to be incorporated in the analysis. The methods handling missing data make various assumptions about the missing mechanism, and their utility in practice depends on whether these assumptions apply in a specific application. Ramakrishnan and Wang (2005) proposed a method (MDT) to handle nonignorable missing data, where missing is due to the observations exceeding an unobserved threshold. Assuming that the observations arise from a truncated normal distribution, they suggested an EM algorithm to simplify the estimation.In this dissertation the EM algorithm is …

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Public: An Exploration Of Community, Environment, And Technology, Christopher John Malven Jan 2006

Public: An Exploration Of Community, Environment, And Technology, Christopher John Malven

Theses and Dissertations

This project examines the potential of computer technology to enhance navigation within, and incorporate information-sharing into, the public urban environment.

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A Study Of The Relationship Between School Climate And Student Performance On The Virginia Standards Of Learning Tests In Elementary Schools, Victoria Lee Thomasson Jan 2006

A Study Of The Relationship Between School Climate And Student Performance On The Virginia Standards Of Learning Tests In Elementary Schools, Victoria Lee Thomasson

Theses and Dissertations

Educators are examining many aspects of schools as they find ways to help students improve their performance on standardized tests in order to meet both federal and state standards. This study examined the relationship between organizational climate and student achievement on the Virginia Standards of Learning tests. A total of 1,061 teachers in 47 schools across the Commonwealth of Virginia responded to the climate survey. The survey instrument was the Organizational Health Inventory for Elementary Schools (OHI-E). This brief survey instrument examined five aspects of school climate. They were Teacher Affiliation, Collegial Leadership, Resource Influence, Institutional Integrity, and Academic Emphasis. …

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Evaluating Surface Area-Basin Volume Relationships For Prairie Potholes, Mike A. Davis Jan 2006

Evaluating Surface Area-Basin Volume Relationships For Prairie Potholes, Mike A. Davis

Theses and Dissertations

Establishing a relationship between surface area and volume of prairie potholes provides a simple method to estimate changes in water storage across the landscape. Applications include better prediction of floods and improved design for wetland restoration. Length, width, depth, surface area, and volumes were surveyed for eighty two potholes within the upper Turtle River watershed which lies sixty kilometers west of Grand Forks, ND. These data were used to determine the relationship and uncertainty between pothole surface and volume. Chi squared tests defined distributions of each variable. F and T statistical tests resolved similarities in variance and mean. The eighty …

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