Digital Commons Network^™

Lightweight Federation Of Non-Cooperating Digital Libraries, Rong Shi

Computer Science Theses & Dissertations

This dissertation studies the challenges and issues faced in federating heterogeneous digital libraries (DLs). The objective of this research is to demonstrate the feasibility of interoperability among non-cooperating DLs by presenting a lightweight, data driven approach, or Data Centered Interoperability (DCI). We build a Lightweight Federated Digital Library (LFDL) system to provide federated search service for existing digital libraries with no prior coordination.

We describe the motivation, architecture, design and implementation of the LFDL. We develop, deploy, and evaluate key services of the federation. The major difference to existing DL interoperability approaches is one where we do not insist on …

Static And Modal Analysis Of The Magnetic Levitation Vehicle, Santosh Kumar Desetty

Mechanical & Aerospace Engineering Theses & Dissertations

The magnetic levitation train project at Old Dominion University has been stalled due to many technical problems. The control system is the main component of the vehicle, which is supposed to maintain an intended gap of 1 cm between the vehicle and the track while traveling, hence providing a smooth ride. The goal of the project is to document the mathematics of the complete system so that the control algorithm can be implemented and modified with the expectation of obtaining an improved levitation and propulsion.

The complete system includes the vehicle, the track, and the concrete guide-way. The focus of …

Rapid Prototyping For The Design Of Virtual Worlds, Prabhu V. Krishnan

Electrical & Computer Engineering Theses & Dissertations

Development of Virtual Reality (VR) applications is challenging where application developers are required to have expertise in the target VR technologies along with the problem domain expertise. New VR technologies impose a significant learning curve to even the most experienced VR developer. The proposed solution relies on synthesis to automate the migration of a VR application to a new unfamiliar VR platform/technology. To solve the problem, the Common Scene Definition Framework (CSDF) was developed, that serves as a superset/model representation of the target virtual world. Input modules were developed to populate the framework with the capabilities of the virtual world …

Factors Predicting Teacher Satisfaction And Retention In The Hampton City Schools Teacher Induction Program, Gale A. Lee

Theses and Dissertations in Urban Services - Urban Education

This descriptive and correlational study used a mixed methodology of both quantitative and qualitative data collection strategies to identify factors that predict new teacher satisfaction and retention in the Hampton City Schools' teacher induction program. In the first phase of the study, a researcher-developed questionnaire was mailed to 657 Hampton City Schools' elementary, middle, and high school teachers with 0–5 years of experience and was returned by 40 percent (n = 226) of the sample. The first phase of the study utilized a 31-item teacher questionnaire. The first section of this questionnaire requested demographic information, which helped to categorize teachers …

Statistical Analysis Of Longitudinal And Multivariate Discrete Data, Deepak Mav

Mathematics & Statistics Theses & Dissertations

Correlated multivariate Poisson and binary variables occur naturally in medical, biological and epidemiological longitudinal studies. Modeling and simulating such variables is difficult because the correlations are restricted by the marginal means via Fréchet bounds in a complicated way. In this dissertation we will first discuss partially specified models and methods for estimating the regression and correlation parameters. We derive the asymptotic distributions of these parameter estimates. Using simulations based on extensions of the algorithm due to Sim (1993, Journal of Statistical Computation and Simulation, 47, pp. 1–10), we study the performance of these estimates using infeasibility, coverage probabilities of the …

The Straggling Green's Function Method For Ion Transport, Steven Andrew Walker

Mathematics & Statistics Theses & Dissertations

For many years work has been conducted on developing a concise theory and method for HZE ion transport capable of being validated in the laboratory. Previous attempts have ignored dispersion and energy downshift associated with nuclear fragmentation and energy and range straggling. Here we present a Green's function approach to ion transport that incorporates these missing elements. This work forms the basis for a new version of GRNTRN, a Green's function transport code. Comparisons of GRNTRN predictions and laboratory results for an ⁵⁶Fe ion beam with average energy at the target of one GeV/amu or more are presented for …

An Application And Evaluation Of A Methodology For Testing Operational Level Training Simulations, Karl Dean Neal

Computational Modeling & Simulation Engineering Theses & Dissertations

The Virginia Modeling, Analysis and Simulation Center has developed a methodology for testing operational-level training simulation systems. The methodology is built on analyses of the military tasks that an operational-level simulation is intended to train. These tasks are derived from the U.S. Department of Defense Universal Joint Task List. The methodology analyzes the categories of capabilities the simulation should have to support those tasks based on operational-level-military entities and actions. Cross-referencing the tasks and capabilities leads to functionality items the simulation should have. The methodology focuses on training joint force command tasks and decision making at the operational level of …

The Effects Of Parcels And Latent Variable Scores On The Detection Of Interactions In Structural Equation Modeling, Thomas D. Fletcher

Psychology Theses & Dissertations

Numerous theories in the behavioral and organizational sciences involve the regression of an outcome variable on component terms and their product to evaluate interaction effects. There are numerous statistical difficulties with this multiple regression approach. The most serious is measurement error, requiring the use of structural equation modeling. Jöreskog and Yang (1996) described a nonlinear structural equation modeling procedure that incorporates mean structures in the covariance analysis. They demonstrated that only one indicator for the product term is necessary for model identification. Unfortunately, the Jöreskog-Yang procedure leads to biased estimates of the product coefficient. In this dissertation, I propose that …

Correlation And Causes Of Fifth Order Cycles Within The Upper Cretaceous Eagle Formation, Bighorn Basin Of Wyoming, Kimberly Ann Johnson

OES Theses and Dissertations

Cyclic stratification was examined in the Upper Cretaceous (Santonian-Campanian) section (Eagle Formation) within the Bighorn Basin of Wyoming. Of particular concern was the 10³ to 10⁴ year band, which in marine settings has been attributed to orbital forcing (Milankovitch cyclicity). A series of 19 sections were measured through the Virgelle Member of the Eagle Formation. Most were measured on the “J”-shaped escarpment that constitutes the nose and north flank of the Thermopolis anticline. Several others were measured at sites up to 30 km to the northwest along paleo-shoreline. In the study, detailed thickness data of all sections and …

Shape Memory Alloy Applications On Control Of Thermal Buckling, Panel Flutter And Random Vibration Of Composite Panels, Xinyun Guo

Mechanical & Aerospace Engineering Theses & Dissertations

Shape Memory Alloy (SMA) has a unique ability to recover large prestrain (up to 8∼10% elongation for Nitinol, a typical SMA material) completely when the alloy is heated (e.g. aerodynamic heating) above the austenite finish temperature Af. An innovative concept is to utilize the large recovery stress by embedding the prestrained SMA in a traditional fiber-reinforced laminated composite plate, which is called SMA hybrid composite (SMAHC) plate. In this research, static thermal and aerothermal deflections, dynamic panel flutter and random response are investigated for traditional composite plates and SMAHC plates under combined aerodynamic, random and thermal loads by employing nonlinear …

Design And Implementation Of One And Two-Degree-Of-Freedom Magnetic Suspension And Balance Systems, Mark W. Adams

Electrical & Computer Engineering Theses & Dissertations

The main objectives of this research were to design and implement one and two-degree-of-freedom (1 DOF and 2-DOF) magnetic levitation systems to levitate permanent magnet cores contained in PVC pipes, 8.4 cm and 76.2 cm in length, respectively. This project used the components of a Magnetic Suspension and Balance System (MSBS) that is being built to provide obstruction free positioning of test models in six degrees of freedom (6-DOF) inside the Princeton University/Office of Naval Research High Reynolds Number Test Facility (HRTF). The HRTF, a specialized wind tunnel designed to simulate undersea conditions by creating a low-speed, 3500 PSI air …

Creating Software [Sic] Environments On An M-Node Beowulf Cluster To Execute Discrete-Event Simulations, Jermaine Fitz-Gerald Headley

Electrical & Computer Engineering Theses & Dissertations

This thesis describes the development of a software tool that facilitates the creation of software environments that make a simulation tool execute k replications of an application program on several nodes of an M-node Beowulf cluster. It is assumed that each cluster-node consists of p processors. The p processors that are contained in the master cluster-node are termed master processors, and the p processors that are contained in a slave cluster-node are termed slave processors. The slave processors are used to execute the replications, while the master processors are dedicated to schedule the replications and process other housekeeping chores. For …

A Novel Approach For Reducing The Asymptotic Computational Complexity Of Maximum Likelihood Multiuser Receivers In Ds-Cdma Systems, Syed Rizvi

Electrical & Computer Engineering Theses & Dissertations

Multiuser detection is a technique to improve the capacity and coverage in a code division multiple access (CDMA) system. Being a critical component of this technique, the maximum likelihood (ML) multiuser receiver has received extensive study. Multiuser detection is an important technology in wireless CDMA systems for improving both data rate as well as the user capacity. However, the computational complexity of this receiver prevents from the widespread use of this technique. Due to the high computational complexity, most of the CDMA systems today and in the near future will continue to use the conventional match filter with comparatively low …

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: James River (1985-2004), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Peter L. Morton, Frederick A. Hoffman

Status and Trends for Virginia Chesapeake Bay

A marked decline in the water quality of the Chesapeake Bay has occurred over the past several decades. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality. The results of concentrated research efforts in the late 1970s and early 1980s stimulated the establishment of Federal and state directives to better manage the Chesapeake Bay watershed. By way of the …

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: Rappahannock River (1985-2004), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Peter L. Morton, Suzanne C. Doughten, Frederick A. Hoffman

Status and Trends for Virginia Chesapeake Bay

A marked decline in the water quality of the Chesapeake Bay has occurred over the past several decades. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality. The results of concentrated research efforts in the late 1970s and early 1980s stimulated the establishment of Federal and state directives to better manage the Chesapeake Bay watershed. By way of the …

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2004), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman

Status and Trends for Virginia Chesapeake Bay

A marked decline in the water quality of the Chesapeake Bay has occurred over the past several decades. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality. The results of concentrated research efforts in the late 1970s and early 1980s stimulated the establishment of Federal and state directives to better manage the Chesapeake Bay watershed. By way of the …

Supervisor Perceptions Of The Quality Of Troops To Teachers Program Completers And Program Completer Perceptions Of Their Preparation To Teach: A National Survey, William A. Owings, Leslie S. Kaplan, John Nunnery, Robert Marzano, Steven Myran, David Blackburn

Educational Leadership & Workforce Development Faculty Publications

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During winter/spring, 2005, 2,103 Troops to Teachers (T3) program completers and their school administrators from 49 states and the District of Columbia were surveyed to determine whether T3s were more effective in the classroom than traditionally prepared teachers who had comparable years of teaching experience. Respondents also returned information about their schools’ demographics, views about their teacher certification preparation program, and information about themselves, their teaching behaviors, and future plans. Sixty-one percent of the respondents returned completed surveys.

Secondary Mathematics Teachers' Perceptions Of The Achievement Gap, Linda Bol, Robert Q. Berry Iii

Educational Leadership & Workforce Development Faculty Publications

The purpose of this study was to survey the perceptions of secondary mathematics teachers on factors contributing to the achievement gap and ways to reduce this gap. National Council of the Teachers of Mathematics (NCTM) members were surveyed, and a total of 379 secondary teachers responded. Overall, respondents were most likely to attribute the achievement gap to student characteristics, such as differences in motivational levels, work ethic, and family support. Furthermore, teachers from schools with a higher population of White students were more likely to attribute the gap to student characteristics than were teachers in schools with higher percentages of …

Bounds On Element Order In Rings Z(M) With Divisors Of Zero, C. H. Cooke

Mathematics & Statistics Faculty Publications

If p is a prime, integer ring Zp has exactly ¢¢(p) generating elements ω, each of which has maximal index Ip(ω) = (p) = p − 1. But, if m = ΠRJ = ₁p^αJ_J is composite, it is possible that Zm does not possess a generating element, and the maximal index of an element is not easily discernible. Here, it is determined when, in the absence of a generating element, one can still with confidence place bounds on the maximal index. Such a bound is usually less than ¢(m …

A Comparison Of The Canons Of Science Used In Positivistic Research And Constructivist/Naturalistic Research, Ipek Bozkurt, Andres Sousa-Poza

Engineering Management & Systems Engineering Faculty Publications

In this paper, the canons of science which are crucial for positivistic, empirical research and constructivist/naturalistic research will be identified, described, compared and discussed. Although there are common canons which are often used in papers throughout literature, it would be beneficial to set a common ground for the identification and use of the canons. The canons used in positivistic research will differ from the canons used in constructivist/ naturalistic research. This paper will analyze major publications (papers, books, etc.) exploring the canons either directly or indirectly, and will provide a link between major characteristics of two different research philosophies and …

Simulations Of Nanopore Formation And Phosphatidylserine Externalization In Lipid Membranes Subjected To A High-Intensity, Ultrashort Electric Pulse, Q. Hu, R. P. Joshi, K. H. Schoenbach

Bioelectrics Publications

A combined MD simulator and time dependent Laplace solver are used to analyze the electrically driven phosphatidylserine externalization process in cells. Time dependent details of nanopore formation at cell membranes in response to a high-intensity (100kV∕cm), ultrashort (10ns) electric pulse are also probed. Our results show that nanosized pores could typically be formed within about 5ns. These predictions are in very good agreement with recent experimental data. It is also demonstrated that defect formation and PS externalization in membranes should begin on the anode side. Finally, the simulations confirm that PS externalization is a nanopore facilitated event, rather than the …

Implementing Simple Protocols In Multiple Processors Control Applications, Steve Hsiung, Tyson Mccall, Corinne Ransberger

Engineering Technology Faculty Publications

Using microprocessor/microcontroller in various control applications is not only one of the major topics in Engineering Technology curricula, but also of interest in industry applications. To accomplish it correctly the process of designing application programs starts from the individual module development through extensive testing, verification, and modification. Applying these developed modules in a useful manner requires the links and integrations that lead to the practical project implementation. Frequently, in students' senior project designs and faculty's research plans, the microprocessor/microcontroller resources become scarce or cause conflicts during the modules' integration stage. To accommodate the shortfall of the resources and resolve any …

Demonstration Of Toxicity To Fish And To Mammalian Cells By Pfiesteria Species: Comparison Of Assay Methods And Strains, Joann M. Burkholder, Andrew S. Gordon, Peter D. Moeller, J. Mac Law, Kathryn J. Coyne, Alan J. Lewitus, John S. Ramsdell, Harold G. Marshall, Nora J. Deamer, S. Craig Cary, Jason W. Kempton, Steven L. Morton, Parke A. Rublee

Biological Sciences Faculty Publications

Toxicity and its detection in the dinoflagellate fish predators Pfiesteria piscicida and Pfiesteria shumwayae depend on the strain and the use of reliable assays. Two assays, standardized fish bioassays (SFBs) with juvenile fish and fish microassays (FMAs) with larval fish, were compared for their utility to detect toxic Pfiesteria. The comparison included strains with confirmed toxicity, negative controls (noninducible Pfiesteria strains and a related nontoxic cryptoperidiniopsoid dinoflagellate), and P. shumwayae strain CCMP2089, which previously had been reported as nontoxic. SFBs, standardized by using toxic Pfiesteria (coupled with tests confirming Pfiesteria toxin) and conditions conducive to toxicity expression, reliably detected …

Review Of Internet Invention: From Literacy To Electracy, By Gregory L. Ulmer, 2003, Alan Clinton

Reconstruction: Studies in Contemporary Culture

No abstract provided.

Perceptions Of The Mathematics Achievement Gap: A Survey Of Nctm Membership, Robert Q. Berry, Linda Bol

Educational Leadership & Workforce Development Faculty Publications

No abstract provided.

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2003), Daniel M. Dauer

Status and Trends for Virginia Chesapeake Bay

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded and some areas and indicators show continuing degradation. Progress in reducing nutrient inputs has made demonstrable improvements and we expect that continued progress toward nutrient reduction goals, along with appropriate fisheries management and chemical contaminant controls, will result in additional improvements to the Bay. Findings from the last 18 years of the monitoring programs are highlighted below. In 1995, the Virginia DEQ instituted changes to its analytical techniques for …

Effect Of Humic Substance Photodegradation On Bacterial Growth And Respiration In Lake Water, Alexandre M. Anesio, William Granéli, George R. Aiken, David J. Kieber, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

This study addresses how humic substance (HS) chemical composition and photoreactivity affect bacterial growth, respiration, and growth efficiency (BGE) in lake water. Aqueous solutions of HSs from diverse aquatic environments representing different dissolved organic matter sources (autochthonous and allochthonous) were exposed to artificial solar UV radiation. These solutions were added to lake water passed through a 0.7-μm pore-size filter (containing grazer-free lake bacteria) followed by dark incubation for 5, 43, and 65 h. For the 5-h incubation, several irradiated HSs inhibited bacterial carbon production (BCP) and this inhibition was highly correlated with H₂O₂ photoproduction. The H_{2 …}

Complex System Transformation: A System Of Systems Engineering (Sose) Perspective, Charles B. Keating, Andres Sousa-Poza, Samuel Kovacic

Engineering Management & Systems Engineering Faculty Publications

The purpose of this paper is to develop a perspective for complex system transformation from a System of Systems Engineering (SoSE) viewpoint. This is a first attempt to make explicit a SoSE viewpoint on complex system transformation. As such, the formulation is intended to escalate the dialog and integrate the current state of understanding with respect to the nature, utility, and implications of complex system transformation in SoSE terms. To achieve our purpose we will: (1) present a short introduction that provides an essential background for SoSE, (2) provide five fundamental systems concepts that underlie a SoSE perspective of complex …

A Comparison Of Esomeprazole And Lansoprazole For Control Of Intragastric Ph In Patients With Symptoms Of Gastro-Oesophageal Reflux Disease, D. A. Johnson, T. Stacy, M. Ryan, T. Wootton, J. Willia, K. Hornbuckle, W. Brooks, M. Doviak

Mathematics & Statistics Faculty Publications

Background: Intragastric acid suppression is the most direct measure of the pharmacodynamic efficacy of proton pump inhibitors, which are the most effective drugs for acid-related diseases.

Aim: To compare the effectiveness of once and twice daily dosing of lansoprazole and esomeprazole in controlling intragastric acidity ( target gastric pH > 4.0) over a 24-hour period.

Methods: In an open-label, two-way crossover study, 45 Helicobacter pylori-negative patients with gastro-oesophageal reflux disease were randomized to receive one of two regimens: 30 mg lansoprazole or esomeprazole 40 mg once daily. Intragastric pH was assessed by 24-hour pH monitoring on day 5 of each regimen. …

Kinetic Structure Simulations Of Nematic Polymers In Plane Couette Cells. Ii: In-Plane Structure Transitions, M. Gregory Forest, Ruhai Zhou, Qi Wang

Mathematics & Statistics Faculty Publications

Nematic, or liquid crystalline, polymer (LCP) composites are composed of large aspect ratio rod-like or platelet macromolecules. This class of nanocomposites exhibits tremendous potential for high performance material applications, ranging across mechanical, electrical, piezoelectric, thermal, and barrier properties. Fibers made from nematic polymers have set synthetic materials performance standards for decades. The current target is to engineer multifunctional films and molded parts, for which processing flows are shear-dominated. Nematic polymer films inherit anisotropy from collective orientational distributions of the molecular constituents and develop heterogeneity on length scales that are, as yet, not well understood and thereby uncontrollable. Rigid LCPs in …