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Factors That Influence The Adoption Of Agricultural Conservation Programs In Northwest Arkansas, Edison Anthony Froelich 2010 University of Arkansas, Fayetteville

Factors That Influence The Adoption Of Agricultural Conservation Programs In Northwest Arkansas, Edison Anthony Froelich

Theses and Dissertations

A survey was developed and administered to agricultural producers in Northwest Arkansas in order to better understand producer awareness of, application for and participation in six federal and state conservation programs available in Arkansas: the Environmental Quality Incentives Program, the Conservation Reserve Enhancement Program, the Arkansas Revolving Loan Program, the Arkansas Nonpoint Pollution Management Program , the Arkansas Soil Nutrient and Poultry Litter Application and Management Program, and the Surplus Poultry Litter Removal Incentives Cost Share Program. Survey results found that less than half of the sample was aware of any one of the programs. A logit model was developed to ...


Redox-Magnetohydrodynamic (Mhd) Microfluidics: Fundamentals, Optimization, And Applications To Analytical Chemistry, Melissa Christine Weston 2010 University of Arkansas, Fayetteville

Redox-Magnetohydrodynamic (Mhd) Microfluidics: Fundamentals, Optimization, And Applications To Analytical Chemistry, Melissa Christine Weston

Theses and Dissertations

Microfluidic systems are of great interest in analytical chemistry for the development of lab-on-a-chip devices. This dissertation describes fundamental investigations of magnetohydrodynamics with added redox species (redox-MHD) as a new microfluidic approach for use in analytical applications. Redox-MHD is attractive because it offers a unique combination of desirable features that are otherwise only available separately with individual micropumps. Redox-MHD is compatible with aqueous and nonaqueous solutions, does not require moving parts, easily reverses flow direction, and requires only low voltages. An ion flux is generated from the oxidation or reduction of an electroactive species at specific locations by activated electrodes ...


Rademacher-Type Formulas For Restricted Partition And Overpartition Functions, Andrew Sills 2010 Georgia Southern University

Rademacher-Type Formulas For Restricted Partition And Overpartition Functions, Andrew Sills

Mathematical Sciences Faculty Publications

A collection of Hardy-Ramanujan-Rademacher type formulas for restricted partition and overpartition functions is presented, framed by several biographical anecdotes.


The K-Cores Of A Graph, Allan Bickle 2010 Western Michigan University

The K-Cores Of A Graph, Allan Bickle

Dissertations

Full abstract attached as supplemental file.


Inner-Shell Photodetachment Of Transition Metal Negative Ions, Ileana Dumitriu 2010 Western Michigan University

Inner-Shell Photodetachment Of Transition Metal Negative Ions, Ileana Dumitriu

Dissertations

This thesis focuses on the study of inner-shell photodetachment of transition metal negative ions, specifically Fe¯ and Ru¯. Experimental investigations have been performed with the aim of gaining new insights into the physics of negative atomic ions and providing valuable absolute cross section data for astrophysics. The experiments were performed using the X-ray radiation from the Advanced Light Source, Lawrence Berkeley National Laboratory, and the merged-beam technique for photoion spectroscopy.

Negative ions are a special class of atomic systems very different from neutral atoms and positive ions. The fundamental physics of the interaction of transition metal negative ions with photons ...


Could Alice Find The Elusive Higgs?, Tyler Williams 2010 California Polytechnic State University - San Luis Obispo

Could Alice Find The Elusive Higgs?, Tyler Williams

Physics

The Higgs boson is the theoretical mechanism for creating the mass of particles. Although it has never been seen, the CERN Large Hadron Collider (LHC) is the most likely place for it to be created in the laboratory. The ALICE (A Large Ion Collider Experiment) detector is focused on the study of heavy ion collisions at the LHC and was not designed to find the Higgs boson; however, there is a chance it could be detected there. Although the luminosity (collision rate) for PbPb collisions is much lower than that for pp collisions, PbPb collisions have a higher probability to ...


Proton Capture Reactions And Network Calculations On 46Ti, 64Zn, 114Sn And 116Sn Relevant To The Rp-Process, Ravin S. T. Kodikara 2010 Western Michigan University

Proton Capture Reactions And Network Calculations On 46Ti, 64Zn, 114Sn And 116Sn Relevant To The Rp-Process, Ravin S. T. Kodikara

Dissertations

The rp-process makes an important contribution to the stellar nucleosynthesis by producing many of the light proton rich nuclei. Successive proton captures on seed nuclei followed by occasional β-decays and electron captures are the key features of this mechanism. For a detailed rp-process analysis, proton capture cross sections and reaction rates are essential. However, the lack of experimental data forces the researcher to largely depend on statistical model predictions.

This dissertation research is an attempt to investigate the proton captures of four particular nuclides; 46Ti, 64Zn, 114Sn and 116Sn. At Western Michigan University Van de Graaff ...


Robust Interval Estimation Of A Treatment Effect In Observational Studies Using Propensity Score Matching, Scott F. Kosten 2010 Western Michigan University

Robust Interval Estimation Of A Treatment Effect In Observational Studies Using Propensity Score Matching, Scott F. Kosten

Dissertations

Estimating the treatment effect between a treatment group and a control group in an observational study is a challenging problem in statistics. Without random assignment of subjects, there are likely to be differences between the treatment group and control group on a set of baseline covariates. If one of these baseline covariates is correlated to the response variable, then the difference in sample means between the groups is likely to be a biased estimate of the true treatment effect.

Propensity score matching has become an increasingly popular strategy for reducing bias in estimates of the treatment effect. This reduction in ...


Dielectronic Recombination For Aluminum-Like Ions And Photoabsorption Cross Sections For Magnesium Ions At The K-Edge, Shahin Ahmed Abdel-Azim Abdel Naby 2010 Western Michigan University

Dielectronic Recombination For Aluminum-Like Ions And Photoabsorption Cross Sections For Magnesium Ions At The K-Edge, Shahin Ahmed Abdel-Azim Abdel Naby

Dissertations

Accurate and reliable recombination data are needed for modeling the ions in the finitedensity plasmas that may take place in solar flares and in divertors of magnetically confined fusion devices such as the International Thermonuclear Experimental Reactor (ITER). Dielectronic recombination (DR) is the dominant recombination mechanism in photoionized and collisionally-ionized plasmas. DR rate coefficients for M-shell argon ions have been calculated using a configuration-average approach. DR rate coefficients for the aluminumlike isoelectronic sequence are instead calculated using the state-of-the-art multiconfiguration Breit-Pauli (MCBP) atomic structure and collision code AUTOSTRUCTURE. Good agreement is obtained with the measurements from the Heidelberg heavy-ion Test ...


Active Bundles For Protecting Confidentiality Of Sensitive Data Throughout Their Lifecycle, Lotfi Ben Othmane 2010 Western Michigan University

Active Bundles For Protecting Confidentiality Of Sensitive Data Throughout Their Lifecycle, Lotfi Ben Othmane

Dissertations

Protecting confidentiality of shared sensitive data requires satisfying conflicting needs for disseminating data and preventing unauthorized data disclosures. We propose a solution named the active bundles scheme for protecting sensitive data from their disclosures to unauthorized parties during their dissemination. The scheme protects data throughout their entire lifecycle, from data creation through their dissemination to their evaporation or apoptosis (a partial or complete self-destruction, respectively).

An active bundle packages together sensitive data, metadata, and a virtual machine (VM) specific to the bundle. Metadata contain information related to the use of data, including data access control and dissemination policies. A VM ...


Confidence Intervals And Tests On The Difference Of Means Of Two Delta Distributions, Karen Grace Villarente Rosales 2010 Western Michigan University

Confidence Intervals And Tests On The Difference Of Means Of Two Delta Distributions, Karen Grace Villarente Rosales

Dissertations

Various research fields produce data that are lognormally distributed and inflated with zero values. This type of data follows a delta distribution. In this study, we want to extensively investigate different interval and hypothesis testing methods for comparing the means of two delta populations to see which methods are optimal under different conditions of the populations.

For confidence intervals, existing MVUE methods are extended to two sample cases and compared to classical and two proposed robust methods. We investigated the performance of the classical Student's t, Welch t, and Wilcoxon-based interval to see if these methods really perform badly ...


Integrated Approach For The Assessment And Development Of Groundwater Resources In Arid Lands: Applications In The Quetta Valley, Pakistan, Zhanay Jay Sagin Sagintayev 2010 Western Michigan University

Integrated Approach For The Assessment And Development Of Groundwater Resources In Arid Lands: Applications In The Quetta Valley, Pakistan, Zhanay Jay Sagin Sagintayev

Dissertations

The lack of adequate field measurements (e.g., precipitation and stream flow) and difficulty in obtaining them often hampers the construction and calibration of rainfall-runoff models over many of the world’s watersheds, leaving key elements of the hydrologic cycle unconstrained. I adopted methodologies that rely heavily on readily available remote sensing datasets as viable alternatives and useful tools for assessing, managing, and modeling the water resources of such remote and inadequately gauged regions.

The Soil and Water Assessment Tool was selected for continuous (1998–2005) rainfall-runoff modeling of the northeast part of the Pishin Lora basin (NEPL), a politically ...


Biochemical Characterization Of Theromin, A Novel Leech Inhibitor, And The Interaction Between The Fourth Metalbinding Domain Of Wilson Disease Protein And Its Copper(I) Chaperone Hah1, Brian A. Zeider 2010 Western Michigan University

Biochemical Characterization Of Theromin, A Novel Leech Inhibitor, And The Interaction Between The Fourth Metalbinding Domain Of Wilson Disease Protein And Its Copper(I) Chaperone Hah1, Brian A. Zeider

Dissertations

Theromin, a novel thrombin inhibitor from the leech Theromyzon tessulatum, has been shown to be the strongest inhibitor to date. There has been a lot of attention on direct thrombin inhibitors as a much more efficient drug for anticoagulation therapy. One main reason for the need of strong direct thrombin inhibitors is that the current therapy, heparin, causes alternative clotting events in some patients where antibodies are made to the heparin/thrombin complex and causes clots to occur by different methods. Recently there has been a strong inhibitor from a leech used, hirudin, that can inhibit with a Ki ...


Optimized Algorithms For Predictive Range And Knn Queries On Moving Objects, Rui ZHANG, H.V. JAGADISH, Bing Tian DAI, Kotagiri RAMAMOHANARAO 2010 Singapore Management University

Optimized Algorithms For Predictive Range And Knn Queries On Moving Objects, Rui Zhang, H.V. Jagadish, Bing Tian Dai, Kotagiri Ramamohanarao

Research Collection School Of Information Systems

There have been many studies on management of moving objects recently. Most of them try to optimize the performance of predictive window queries. However, not much attention is paid to two other important query types: the predictive range query and the predictive k nearest neighbor query. In this article, we focus on these two types of queries. The novelty of our work mainly lies in the introduction of the Transformed Minkowski Sum, which can be used to determine whether a moving bounding rectangle intersects a moving circular query region. This enables us to use the traditional tree traversal algorithms to ...


Linkage Of Asteroids And Meteorites By The Study Of Terrestrial Analogs, Daniel Robert Ostrowski 2010 University of Arkansas

Linkage Of Asteroids And Meteorites By The Study Of Terrestrial Analogs, Daniel Robert Ostrowski

Theses and Dissertations

Asteroids are one group of the bodies that can provide insights into the origin and early history of the solar system. Asteroids are considered to be fairly pristine, with alterations only occurring to their surface from the space environment. Studying them provides opportunities to learn about the primordial solar system, its materials, and processes and how it evolved into the current condition. Many asteroids have been discovered, but few have their surface compositions determined. The C and X complexes provide a difficulty in determination because their near infrared spectrum is featureless.

The C asteroids have been long associated with the ...


Two Essays On The Accounting Treatment For Information Technology Expenditures, Kimberly Swanson Church 2010 University of Arkansas, Fayetteville

Two Essays On The Accounting Treatment For Information Technology Expenditures, Kimberly Swanson Church

Theses and Dissertations

The current accounting measurement and reporting system is ill-equipped to provide intangible investment information that is decision useful for stakeholders in the information economy. Potentially relevant intangible items are not reported on the balance sheet, since current standards mandate the immediate expensing of these intangible items. Presumably FASB's uncertainty with the fundamental issues of extent and timing of future benefits to the firm has led to concerns with relevance, reliability, and objectivity of capitalizing some intangibles, which results in potential long term value generating expenditures being immediately expensed on the income statement. Prior research has demonstrated extent and timing ...


Investigation Of The Rheology, Cure Kinetics, And Thermo-Mechanical Properties Of Grc-A Loaded With Zeolites, Tracy Brown 2010 Clark Atlanta University

Investigation Of The Rheology, Cure Kinetics, And Thermo-Mechanical Properties Of Grc-A Loaded With Zeolites, Tracy Brown

ETD Collection for AUC Robert W. Woodruff Library

Phenylethynyl terminated imides (PETI) are high temperature, high performance matrix resins that can be processed into composites by various methods including resin transfer molding (RTM) arid vacuum assisted resin transfer molding (VARTM). PETI resins have experienced extremely rapid development in recent years, with major emphasis placed on engineering applications that take advantage of their high cured TgS,high thermooxidative stability, high strength to weight ratio, outstanding mechanical properties, and compatibility with RTM and VARTM processing. In recent years the addition of nanoparticles to resin systems has been shown to further enhance the mechanical properties and thermooxidative stability. In this study ...


Seasonal Aggregations Of The Florida Manatee (Trichechus Manatus Latirostris) In The Port Everglades And Intracoastal Regions Of Fort Lauderdale, Florida., Jaime M. Goldman 2010 Nova Southeastern University

Seasonal Aggregations Of The Florida Manatee (Trichechus Manatus Latirostris) In The Port Everglades And Intracoastal Regions Of Fort Lauderdale, Florida., Jaime M. Goldman

HCNSO Student Theses and Dissertations

The Florida manatee (Trichechus manatus latirostris), a subspecies of the West Indian manatee, is one of the most endangered marine mammals in United States waters. The Florida manatee is the only manatee that ranges into subtropical and temperate regions. During the winter months manatees adopt a “refuging strategy” where they aggregate at warm-water sources immediately following decreases in the ambient water temperature to below 20° C (68° F) in order to avoid cold stress syndrome (CSS). During the winter manatees aggregate in warm water refuges, including natural warm water springs and the effluent discharges of power plants.

The purpose of ...


Detention Basins For Phosphorus And Sediment Control In Clark County, Nevada, Amina Rashid Lodhi 2010 University of Nevada, Las Vegas

Detention Basins For Phosphorus And Sediment Control In Clark County, Nevada, Amina Rashid Lodhi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nonpoint source urban stormwater runoff degrades aquatic ecosystems, and causes flooding. To mitigate its effects on natural and human environments best management practices (BMPs) became popular strategies to protect the integrity of water quality. Similarly, to mitigate the effects of stormwater quantity, detention basins (DBs) were put into place as flood control structures. Water quality control remains an unexplored and important aspect of DB utility, particularly, in arid regions. Since DBs are depressions in the earth and retain water over the course of several hours to days after a rain event, they can potentially act as BMPs. A key pollutant ...


Dynamic Distributed Programming And Applications To Swap Edge Problem, Feven Z. Andemeskel 2010 University of Nevada, Las Vegas

Dynamic Distributed Programming And Applications To Swap Edge Problem, Feven Z. Andemeskel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Link failure is a common reason for disruption in communication networks. If communication between processes of a weighted distributed network is maintained by a spanning tree T, and if one edge e of T fails, communication can be restored by finding a new spanning tree, T’. If the network is 2-edge connected, T’ can always be constructed by replacing e by a single edge, e’, of the network. We refer to e’ as a swap edge of e.


The best swap edge problem is to find the best choice of e’, that is, that e which causes the new spanning ...


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