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2008

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Availability And Toxicity Of Nickel To Lotic Periphyton And Macroinvertebrates, Stephanie Marie Bessom Jan 2008

Availability And Toxicity Of Nickel To Lotic Periphyton And Macroinvertebrates, Stephanie Marie Bessom

Browse all Theses and Dissertations

There is a lack of information regarding the bioaccumulation and toxicity of nickel (Ni) to lotic ecosystems. The objective of this study was to investigate the source, uptake, and toxicity of Ni by periphyton and macroinvertebrates (Hyalella azteca and Daphnia magna) in simulated stream ecosystems that included sediment and water. Periphyton were exposed to two types of sediment, a low-organic sandy mixture and a high organic silt, treated with varying levels of Ni. After 96 h, Ni levels in overlying water and periphyton were related to those in sediments, although differences existed between sediment types. Tests with 64Ni added to …

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Motion-Control System Of Bench-Top Ct Scanner, Tarpit Kaushikbhai Patel Jan 2008

Motion-Control System Of Bench-Top Ct Scanner, Tarpit Kaushikbhai Patel

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Computed Tomography (CT) imaging has found applications in many areas such as diagnostic visualization, quantitative estimation, and therapeutic verification. In this wide range of applications, a CT scanner that can provide the data collection schemes of both second- and third-generation data-collection geometries will be an asset for laboratory research. In this thesis project, we developed a mechanical design and constructed a dual-generation CT scanner that provides flexibility in accommodating a wide range of object sizes with minimum scan time. Using 3-D graphical design software, models of the current second-generation CT scanner and possible solutions for modification were simulated. Based on …

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Investigating Nickel Flux And Toxicity In Clay Sediments With Batch And Stream Recirculating Flume Experiments, Christina Elizabeth Cloran Jan 2008

Investigating Nickel Flux And Toxicity In Clay Sediments With Batch And Stream Recirculating Flume Experiments, Christina Elizabeth Cloran

Browse all Theses and Dissertations

Using batch and stream recirculating flume experiments to compare and contrast one clayey sediment (Warden Ditch) and two analytical grade clay minerals (montmorillonite and kaolinite), the dynamic interactions between two aquatic stressors (suspended solids and nickel) were explored. Aldrich humic acid was incorporated to demonstrate the mitigating effects of dissolved organic carbon (DOC) on Ni toxicity. The flux of Ni between compartments (dissolved and sorbed) was quantified as a partition/distribution coefficient. The USEPA test organism Daphnia magna (neonates, < 24 h) was utilized to evaluate toxicity in dynamic non-renewal, short-term bioassays. Generally, toxicity showed a linear relationship with turbidity level. Conversely, sorption coefficients were experiment specific, making them difficult to predict and assess. Clay functioned as an adsorbent, scavenging Ni. Results support the hypotheses that solids and metals act as stressors in streams, DOC attenuates the toxicity of Ni, and Ni fluxes quickly between system compartments.

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Cenozoic Antarctic Diatomware/Bugcam: An Aid For Research And Teaching, Sherwood W. Wise, M. Olney, J. M. Covington, V. M. Egerton, S. Jiang, D. K. Kulhanek, S. Ramdeen, H. Schrader, P. A. Sims, A. S. Wood, A. Davis, D. R. Davenport, N. Doepler, W. Falcon, C. Lopez, T. Pressley, O. L. Swedberg, David M. Harwood Jan 2008

Cenozoic Antarctic Diatomware/Bugcam: An Aid For Research And Teaching, Sherwood W. Wise, M. Olney, J. M. Covington, V. M. Egerton, S. Jiang, D. K. Kulhanek, S. Ramdeen, H. Schrader, P. A. Sims, A. S. Wood, A. Davis, D. R. Davenport, N. Doepler, W. Falcon, C. Lopez, T. Pressley, O. L. Swedberg, David M. Harwood

Department of Earth and Atmospheric Sciences: Faculty Publications

Cenozoic Antarctic DiatomWare/BugCam© is an interactive, icon-driven digital-image
database/software package that displays over 500 illustrated Cenozoic Antarctic diatom taxa along with original descriptions (including over 100 generic and 20 family-group descriptions). This digital catalog is designed primarily for use by micropaleontologists working in the field (at sea or on the Antarctic continent) where hard-copy literature resources are limited. This new package will also be useful for classroom/lab teaching as well as for any paleontologists making or refining taxonomic identifications at the microscope. The database (Cenozoic Antarctic DiatomWare) is displayed via a custom software program (BugCam) …

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New Approaches And Progress In The Use Of Polar Marine Diatoms In Reconstructing Sea Ice Distribution, A. Leventer, L. Armand, David M. Harwood, R. Jordan, R. Ligowski Jan 2008

New Approaches And Progress In The Use Of Polar Marine Diatoms In Reconstructing Sea Ice Distribution, A. Leventer, L. Armand, David M. Harwood, R. Jordan, R. Ligowski

Department of Earth and Atmospheric Sciences: Faculty Publications

Reconstructing the paleo-latitudinal extent of sea ice in the Southern Ocean over time can be accomplished using modern diatom data. However, it is more difficult to extend the utility of diatom proxies farther back in time, to time periods characterized by species that are now extinct, since we are uncertain of the paleoenvironmental affiliation of those species we can’t observe in modern assemblages. We propose several research strategies to strengthen our ability to use diatom data to reconstruct sea ice history. These tactics include the evaluation of specific morphologic characteristics and distinct taxa, as well as the identification of specific …

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On Well-Balanced Schemes For Non-Equilibrium Flow With Stiff Source Terms, W. Wang, C.-W. Shu, Helen Yee Jan 2008

On Well-Balanced Schemes For Non-Equilibrium Flow With Stiff Source Terms, W. Wang, C.-W. Shu, Helen Yee

United States National Aeronautics and Space Administration: Publications

In the modeling of unsteady reactive problems, the interaction of turbulence with finiterate chemistry introduces a wide range of space and time scales, leading to additional numerical difficulties. A main difficulty stems from the fact that most numerical algorithms used in reacting flows were originally designed to solve non-reacting fluids. As a result, spatial stiffness due to reacting source terms and turbulence/chemistry interaction are major stumbling blocks to numerical algorithm development. One of the important numerical issues is the proper numerical treatment of a system of highly coupled stiff non-linear source terms, which will result in possible spurious steady state …

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Hydrogeochemistry And Water Quality Of Echo Hills, Joel M. Kimball Jan 2008

Hydrogeochemistry And Water Quality Of Echo Hills, Joel M. Kimball

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Ground water of the Echo Hills area in Clark County, Ohio was investigated for common water contaminants such as nitrate and coliform bacteria. Thirty-four water samples were collected from locations including private wells, streams and a spring. Nine of those samples were selected for nitrogen isotope analysis. Three locations were chosen for a tracer test. Additionally, well log data, historical water quality data, and GIS data were obtained from the Clark County Health Department in Springfield, Ohio. Results show that local agriculture likely has the greatest impact on ground water quality in Echo Hills especially the north-eastern portion, with local …

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Sorption-Induced Static Bending Of Microcantilevers Coated With Viscoelastic Material, Michael J. Wenzel, Fabien Josse, Stephen M. Heinrich, Edwin E. Yaz, P. G. Datskos Jan 2008

Sorption-Induced Static Bending Of Microcantilevers Coated With Viscoelastic Material, Michael J. Wenzel, Fabien Josse, Stephen M. Heinrich, Edwin E. Yaz, P. G. Datskos

Civil and Environmental Engineering Faculty Research and Publications

Absorption of a chemical analyte into a polymercoating results in an expansion governed by the concentration and type of analyte that has diffused into the bulk of the coating. When the coating is attached to a microcantilever, this expansion results in bending of the device. Assuming that absorption (i.e., diffusion across the surface barrier into the bulk of the coating) is Fickian, with a rate of absorption that is proportional to the difference between the absorbed concentration and the equilibrium concentration, and the coating is elastic, the bending response of the coated device should exhibit a first-order behavior. However, for …

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Proposed Preface To Codification Of Statements On Auditing Standards: Principles Governing An Audit Conducted In Accordance With Generally Accepted Auditing Standards, And Proposed Statement On Auditing Standards: Overall Objectives Of The Independent Auditor And The Conduct Of An Audit In Accordance With Generally Accepted Auditing Standards; Exposure Draft (American Institute Of Certified Public Accountants), 2008, September 26, American Institute Of Certified Public Accountants. Auditing Standards Board Jan 2008

Proposed Preface To Codification Of Statements On Auditing Standards: Principles Governing An Audit Conducted In Accordance With Generally Accepted Auditing Standards, And Proposed Statement On Auditing Standards: Overall Objectives Of The Independent Auditor And The Conduct Of An Audit In Accordance With Generally Accepted Auditing Standards; Exposure Draft (American Institute Of Certified Public Accountants), 2008, September 26, American Institute Of Certified Public Accountants. Auditing Standards Board

Exposure Drafts, Comment Letters, and Statements of Position

No abstract provided.

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Audit Sampling, New Edition As Of May 1, 2008; Audit And Accounting Guide:, American Institute Of Certified Public Accountants. Audit Sampling Guide Task Force Jan 2008

Audit Sampling, New Edition As Of May 1, 2008; Audit And Accounting Guide:, American Institute Of Certified Public Accountants. Audit Sampling Guide Task Force

Industry Guides (AAGs), Risk Alerts, and Checklists

No abstract provided.

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Prospective Financial Information With Conforming Changes As Of March 1, 2008; Audit And Accounting Guide, American Institute Of Certified Public Accountants. Financial Forecasts And Projections Task Force Jan 2008

Prospective Financial Information With Conforming Changes As Of March 1, 2008; Audit And Accounting Guide, American Institute Of Certified Public Accountants. Financial Forecasts And Projections Task Force

Industry Guides (AAGs), Risk Alerts, and Checklists

No abstract provided.

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Detailed Geochemistry And K-Ar Geochronology Of The Metamorphic Sole Rocks And Their Mafic Dykes From The Mersin Ophiolite, Southern Turkey, Ömer Faruk Çeli̇k Jan 2008

Detailed Geochemistry And K-Ar Geochronology Of The Metamorphic Sole Rocks And Their Mafic Dykes From The Mersin Ophiolite, Southern Turkey, Ömer Faruk Çeli̇k

Turkish Journal of Earth Sciences

The metamorphic sole rocks at the base of mantle peridotites from the Mersin ophiolite consist of amphibolites and metasedimentary lithologies. Mineral parageneses in the metamorphic sole rocks exhibit amphibolite and greenschist facies assemblages. Geothermobarometric studies based on mineral assemblages and chemical compositions of minerals indicate that average metamorphic temperature during the metamorphism was 522 ± 15 °C and the pressure was less than 5 kb. Amphibolites from the metamorphic sole rocks exhibit geochemical characteristics of a supra-subduction zone (SSZ) type ophiolite, based on their major, trace and rare earth element (REE) compositions. The Th/Nb ratios of the amphibolites are higher …

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On The Origin And Age Of The Arıburnu Beachrock, Gelibolu Peninsula, Turkey, Ahmet Evren Ergi̇nal, Nafi̇ye Kiyak Güneç, Mustafa Bozcu, Ahmet Ertek, Hakan Güngüneş, Ali̇ Sungur, Gülen Türker Jan 2008

On The Origin And Age Of The Arıburnu Beachrock, Gelibolu Peninsula, Turkey, Ahmet Evren Ergi̇nal, Nafi̇ye Kiyak Güneç, Mustafa Bozcu, Ahmet Ertek, Hakan Güngüneş, Ali̇ Sungur, Gülen Türker

Turkish Journal of Earth Sciences

The beachrock formation on the Arıburnu coast situated in the Gelibolu Peninsula has been studied by field observation, thin-section interpretation, physicochemical analyses including ICP-AES and SEM/EDS, and OSL dating. These analyses reveal the presence of different amounts of major (Si, Ca, Mg, K, Fe, Al and Na) and trace elements within the beachrock cement with Si (36.2%) and Ca (32.68%) dominating the overall composition. Beachrocks composed of highly-fractured and friable beds reach a total thickness of 80 cm extending from +60 cm at the uppermost level down to -1 m at their most seaward extent and grade from conglomerate to …

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Trace Fossils Of The Upper Eocene-Lower Oligocene Transition Of The Manipur, Indo-Myanmar Ranges (Northeast India), Rajkumar Hemanta Singh, Francisco J. Rodriguez Tovar, Soibam Ibotombi Jan 2008

Trace Fossils Of The Upper Eocene-Lower Oligocene Transition Of The Manipur, Indo-Myanmar Ranges (Northeast India), Rajkumar Hemanta Singh, Francisco J. Rodriguez Tovar, Soibam Ibotombi

Turkish Journal of Earth Sciences

A detailed ichnological analysis, for the first time, has been preformed on Upper Eocene-Lower Oligocene Transition of Manipur, Indo-Myanmar Ranges (Northeast India). Previous trace fossil analyses in India are scarce and usually poorly detailed, especially with respect to Cenozoic materials. Sediments from the Disang and Barail groups contain a relatively abundant and moderately diverse trace fossil assemblage that has been characterized at the ichnogenus and ichnospecies level. ?Arenicolites Salter 1857, Helminthopsis tenuis Ksiazkiewicz 1968, Ophiomorpha nodosa Lundgren 1891, Phycodes palmatus (Hall 1852), Planolites montanus Richter 1937, Rhizocorallium jenense Zenker 1836, Thalassinoides paradoxicus (Woodward 1830) and Skolithos linearis (Haldeman 1840) have …

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The Impact Of High Stakes Testing On Highly Able Gifted Students In A Selected High Achieving New Jersey Abbott District And A Selected High Achieving J District As Perceived By Their Teachers And Administrators, Anne Davie Mucci Jan 2008

The Impact Of High Stakes Testing On Highly Able Gifted Students In A Selected High Achieving New Jersey Abbott District And A Selected High Achieving J District As Perceived By Their Teachers And Administrators, Anne Davie Mucci

Seton Hall University Dissertations and Theses (ETDs)

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The Influence Of Teachers Caring Behavior On High School Students Behavior And Grades, Richard M. Miller Jan 2008

The Influence Of Teachers Caring Behavior On High School Students Behavior And Grades, Richard M. Miller

Seton Hall University Dissertations and Theses (ETDs)

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Understanding The Application Of Supported Palladium Catalysts In The Suzuki-Miyaura Cross-Coupling Reaction, Lubabalo Tseliso Bululu Jan 2008

Understanding The Application Of Supported Palladium Catalysts In The Suzuki-Miyaura Cross-Coupling Reaction, Lubabalo Tseliso Bululu

Seton Hall University Dissertations and Theses (ETDs)

.

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Understanding Children's Mathematical Learning: The Relationship To Instruction In Preschool Classrooms, Renee B. Whelan Jan 2008

Understanding Children's Mathematical Learning: The Relationship To Instruction In Preschool Classrooms, Renee B. Whelan

Seton Hall University Dissertations and Theses (ETDs)

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The Use And Interpretation Of The Batería Iii With U.S. Bilinguals, Julie Esparza Brown Jan 2008

The Use And Interpretation Of The Batería Iii With U.S. Bilinguals, Julie Esparza Brown

Dissertations and Theses

Within each classroom, many children excel academically while others struggle. Some students' difficulties are such that they require placement into educational programs different from grade level core and perhaps delivered outside of general education classrooms. For many, special education programs are the lifeline to reach their innate potential. For others misplaced into special education, their opportunities may be truncated. For the past 40 years (Dunn, 1968), disproportionate representation of minority children in some disability categories has been a problem. Educators commonly ask "Is a child's difficulties due to language differences or a learning disability?" One key area of confusion relates …

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Quantifying Twentieth Century Glacier Change In The Sierra Nevada, California, Hassan J. Basagic Jan 2008

Quantifying Twentieth Century Glacier Change In The Sierra Nevada, California, Hassan J. Basagic

Dissertations and Theses

Numerous small alpine glaciers occupy the high elevation regions of the central and southern Siena Nevada, California. These glaciers change size in response to variations in climate and are therefore important indicators of climate change. An inventory based on USGS topographic maps (l :24,000) revealed 1719 glaciers and perennial snow and ice features for a total area of 39.l5 ±7.52 km2. The number of 'true' glaciers, versus non-moving ice, is estimated to be 118, covering 15.87 ± 1.69 Km2. All glaciers were located on north to northeast aspects, at elevations >3000 m. Historical photographs, geologic evidence, …

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Factors Influencing Potato Production In North Dakota, Zoe Taryn Margaux Roberson Zetina Jan 2008

Factors Influencing Potato Production In North Dakota, Zoe Taryn Margaux Roberson Zetina

Agribusiness and Applied Economics

Spatial shifts and structural changes continue to occur in the United States agricultural industry. Researchers have documented that the potato industry has changed in response to demands of consumers, expectations of producers and improvements in research and development. The aim of this study was to provide empirical evidence that both institutional and infrastructural factors are important to potato production in North Dakota. Using secondary county-level potato production data for North Dakota, an empirical model was designed to estimate the direction and impact of growers' expectations of prices, yields and costs on their decision to produce potatoes. The results confirmed that …

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The Valuation Of Agricultural Biotechnology: The Real Options Approach, Ian Marshall Flagg Jan 2008

The Valuation Of Agricultural Biotechnology: The Real Options Approach, Ian Marshall Flagg

Agribusiness and Applied Economics

This study develops a real options model of agbiotechnology and is applied to three genetically modified (GM) traits. Each trait is evaluated as growth options where technical or marketing milestones must be completed before management can exercise the option to invest further in trait development. The real options values are evaluated by employing a binomial tree which is simulated using distributions for random elements within stages of the growth option. Mean option values were negative for the discovery stage for fusarium-resistant wheat and for all but the regulatory submission stage for Roundup Ready wheat. The length of the regulatory submission …

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Examination Of North Dakota's Production, Cost, And Profit Functions: A Quantile Regression Analysis, Jacklin Beatriz Marroquin Jan 2008

Examination Of North Dakota's Production, Cost, And Profit Functions: A Quantile Regression Analysis, Jacklin Beatriz Marroquin

Agribusiness and Applied Economics

This thesis estimates the production, cost, and profit functions for North Dakota agriculture using state-level input-output quantity and price data for the period 1960-2004. A Cobb-Douglas functional form with Hick-neutral technology change is used to measure the contribution of capital, land, labor, materials, energy, and chemical inputs quantities and output quantity using the primal production function; contribution of capital quantity, land quantity, output quantity, labor price, materials price, energy price, and chemical price to cost using the dual restricted cost function; and the contribution of capital quantity, land quantity, labor price, materials price, energy price, chemical price, output price to …

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Logistic Strategies For An Herbaceous Crop Residue-Based Ethanol Production Industry : An Application To Northeastern North Dakota, Jason Enil Middleton Jan 2008

Logistic Strategies For An Herbaceous Crop Residue-Based Ethanol Production Industry : An Application To Northeastern North Dakota, Jason Enil Middleton

Agribusiness and Applied Economics

A mixed integer programming model is developed to determine a logistical design for maximizing rates of return to harvest, storage, transportation, and bioreflning of herbaceous crop residue for production of biofuels and feed for ruminant animals. The primary objective of this research is to identify the optimal location, scale, and number of pretreatment and biorefinery plants in northeastern North Dakota. The pretreatment and biorefinery plants are modeled under the assumption that they utilize recent technological advancement in AFEX and Simultaneous Saccharification and Fermentation, respectively. Potential feedstocks include wheat straw, barley straw, Durum straw, and com stover. Results indicate that the …

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Dublin Core Metadata Harvested Through Oai-Pmh, Amy S. Jackson, Myung-Ja Han, Kurt Groetsch, Megan Mustafoff, Timothy W. Cole Jan 2008

Dublin Core Metadata Harvested Through Oai-Pmh, Amy S. Jackson, Myung-Ja Han, Kurt Groetsch, Megan Mustafoff, Timothy W. Cole

University Libraries & Learning Sciences Faculty and Staff Publications

The introduction in 2001 of the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH) increased interest in and awareness of metadata quality issues relevant to digital library interoperability and the use of harvested metadata to build "union catalogs" of digital information resources. Practitioners have offered wide-ranging advice to metadata authors and have suggested metrics useful for measuring the quality of shareable metadata. Is there evidence of changes in metadata practice in response to such advice and/or as a result of an increased awareness of the importance of metadata interoperability? This paper looks at metadata records created over a six-year period …

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Hypersonic Boundary Layer Receptivity To Acoustic Disturbances Over Cones, Kursat Kara Jan 2008

Hypersonic Boundary Layer Receptivity To Acoustic Disturbances Over Cones, Kursat Kara

Mechanical & Aerospace Engineering Theses & Dissertations

The receptivity mechanisms of hypersonic boundary layers to free stream acoustic disturbances are studied using both linear stability theory (LST) and direct numerical simulations (DNS). A computational code is developed for numerical simulation of steady and unsteady hypersonic flow over cones by combining a fifth-order weighted essentially non-oscillatory (WENO) scheme with third-order total-variation-diminishing (TVD) Runge-Kutta method. Hypersonic boundary layer receptivity to free-stream acoustic disturbances in slow and fast modes over 5-degree, half-angle blunt cones and wedges are numerically investigated. The free-stream Mach number is 6.0, and the unit Reynolds number is 7.8×106/ft. Both the steady and unsteady solutions are obtained …

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The Impact Of The “Universal Voyager Literacy” Reading Program On Reading Achievement And Instructional Practices In An Urban School District, Shanika L. Hope Jan 2008

The Impact Of The “Universal Voyager Literacy” Reading Program On Reading Achievement And Instructional Practices In An Urban School District, Shanika L. Hope

Theses and Dissertations in Urban Studies

Founded in 1994, Voyager Expanded Learning is a provider of K-3 in-school reading programs, as well as K-8 reading intervention programs for school districts throughout the United States. Voyager Universal Literacy's systematic, precise framework fully addresses the five elements of reading instruction, through an explicit succession of ability growth. Voyager Universal Literacy was developed to be a comprehensive program encompassing the subsequent requisites: in-school broad reading program, progress monitoring methods, extensive-day and summer activities, home learning syllabus, implementation monitoring, and on-going professional development. Voyager Universal Literacy Program activities are organized to provide a thorough range and progression for reading instruction. …

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Dgm-Fd: A Finite Difference Scheme Based On The Discontinuous Galerkin Method, Anne Marguerite Fernando Jan 2008

Dgm-Fd: A Finite Difference Scheme Based On The Discontinuous Galerkin Method, Anne Marguerite Fernando

Mathematics & Statistics Theses & Dissertations

Accurate and efficient numerical wave propagation is important in many areas of study such as computational aero-acoustics (CAA). While dissipation and dispersion errors influence the accuracy of a method, efficiency can be assessed by convergence rates and effective adaptability to different mesh structures. Finite difference and finite element methods are commonly used numerical schemes in CAA. Finite difference methods have the advantages of ease of use as well as high order convergence, but often require a uniform grid, and stable boundary closure can be non-trivial. Finite element methods adapt well to different mesh structures but can become difficult to implement …

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The Relationship Between Rural Middle School Student Mathematics Achievement And Classroom Sense Of Community, John E. Donlan Jan 2008

The Relationship Between Rural Middle School Student Mathematics Achievement And Classroom Sense Of Community, John E. Donlan

Educational Leadership & Workforce Development Theses & Dissertations

This study addressed the need for more information about academic growth and achievement in mathematics, and how it relates to sense of community in middle school settings. This was accomplished by applying the Classroom and School Community Inventory (CSCI) construct (Rovai, Wighting, & Lucking, 2004) to all three middle schools in one rural county. The CSCI was utilized to measure sense of community in mathematics classes to determine if differences existed between grades six, seven, and eight, including gender subgroups, among the three middle schools in the same rural county. This study examined academic growth in the subject of mathematics …

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Adaptive Modulation For Cognitive Radios, Gaurav Sharma Jan 2008

Adaptive Modulation For Cognitive Radios, Gaurav Sharma

Masters Theses

"This thesis examines the benefits of using adaptive modulation in terms of spectral efficiency and probability of bit error for cognitive radio networks. In channels that fluctuate dynamically over time, systems that are based upon the conventional methods of fixed modulation formats do not perform well. Adaptive modulation provides many parameters that can be adjusted relative to the channel fading, including data rate, transmit power, instantaneous BER, symbol rate, and channel code rate or scheme. In this thesis, a systematic study on the increase in spectral efficiency obtained by optimally varying combinations of the modulation formats for a cognitive radio …

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