Digital Commons Network^™

A Digital Pressure Sensor Data Acquisition System In A Wind Tunnel Model, John J. Novakoski

Electrical & Computer Engineering Theses & Dissertations

Pressure measurements on wind tunnel models provide an important aid to overall aerodynamic analysis and design of aircraft and vehicles. Most pressure measurements in wind tunnels are made using analog pressure sensors with interfacing electronics that connect to an external data acquisition unit. Some of desirable features of an improved pressure measurement system are that it be: 1) model embeddable, 2) inherently digital in nature, 3) intelligent, and 4) controllable by a remote computer.

An intelligent, model-embedded, eight-channel digital pressure sensor system has been developed and tested in a wind tunnel. The implemented system consists of Micro-Electro-Mechanical System (MEMS) digital …

Strategies For Maintaining Positive Behavior Change Stemming From Functional Behavioral Assessment In Schools, Robert A. Gable, Jo M. Hendrickson

Communication Disorders & Special Education Faculty Publications

Nationwide, schools are struggling to prepare IEP teams and other school personnel to conduct functional behavioral assessment and develop positive behavioral intervention plans and supports. While there is a growing evidence that functional behavioral assessment is effective in identifying the reason(s) behind student misbehavior, less is known about producing positive, long-term changes that are both functionally and socially relevant. Drawing upon the available research, we explore an emerging technology for promoting maintenance and generalization of behavior change. We discuss various strategies and procedures and offer recommendations to IEP teams regarding maintaining positive changes in student behavior that stem from functional …

The Dyke Marsh Preserve Ecosystem, David W. Johnston

Virginia Journal of Science

For over a century, Dyke marsh along the Potomac River just south of Alexandria, VA, has been a favorite site for natural history studies. Despite earlier attempts at diking to create agricultural land and dredging for sand and gravel, the remaining marsh represents the last major tidal freshwater wetland on the upper Potomac River, and is now owned and maintained by the National Park Service as the Dyke Marsh Preserve. In the present paper historical data on physical properties and biota are compared and contrasted with more recent biological investigations to show functioning ecosystem components, interrelationships among the flora and …

Series Operation Of Direct Current Xenon Chloride Excimer Sources, Ahmed El-Habachi, Wenhui Shi, Mohamed Moselhy, Robert H. Stark, Karl H. Schoenbach

Bioelectrics Publications

Stable, direct current microhollow cathode discharges in mixtures of hydrochloric acid, hydrogen, xenon, and neon have been generated in a pressure range of 200–1150 Torr. The cathode hole diameter was 250 μm. Sustaining voltages range from 180 to 250 V at current levels of up to 5 mA. The discharges are strong sources of xenon chloride excimer emission at a wavelength of 308 nm. Internal efficiencies of approximately 3% have been reached at a pressure of 1050 Torr. The spectral radiant power at this pressure was measured as 5 mW/nm at 308 nm for a 3 mA discharge. By using …

Electroporation Dynamics In Biological Cells Subjected To Ultrafast Electrical Pulses: A Numerical Simulation Study, R. P. Joshi, K. H. Schoenbach

Bioelectrics Publications

A model analysis of electroporation dynamics in biological cells has been carried out based on the Smoluchowski equation. Results of the cellular response to short, electric pulses are presented, taking account of the growth and resealing dynamics of transient aqueous pores. It is shown that the application of large voltages alone may not be sufficient to cause irreversible breakdown, if the time duration is too short. Failure to cause irreversible damage at small pulse widths could be attributed to the time inadequacy for pores to grow and expand beyond a critical threshold radius. In agreement with earlier studies, it is …

Quantitative Analysis Of Ultra-Fine Goethite In Rust Layer On Steel Using Mossbauer And X-Ray Diffraction Spectroscopy, Masato Yamashita, Toshihei Misawa, H. E. Townsend, D. C. Cook

Physics Faculty Publications

We have proposed determination procedure of the relative amounts of rust constituents of steel. Mossbauer spectroscopy provides the relative amounts of crystalline rust constituents including ultra-fine crystals. A quantitative analysis of ultra-fine crystals is possible with the resolution of several percent by comparing the Mossbauer results with the relative amounts of rust constituents determined by X-ray diffraction spectroscopy.

The Ups Prototype: An Experimental End-User Service Across E-Print Archives, Herbert Van De Sompel, Thomas Krichel, Michael L. Nelson, Patrick Hochstenbach, Victor Lyapunov, Kurt Maly, Mohammad Zubair, Mohamed Kholief, Xiaoming Liu, Heath O'Connell

Computer Science Faculty Publications

A meeting was held in Santa Fe, New Mexico, October 21-22, 1999, to generate discussion and consensus about interoperability of publicly available scholarly information archives. The invitees represented several well known e-print and report archive initiatives, as well as organizations with interests in digital libraries and the transformation of scholarly communication. The central goal of the meeting was to agree on recommendations that would make the creation of end-user services -- such as scientific search engines and linking systems -- for data originating from distributed and dissimilar archives easier. The Universal Preprint Service (UPS) Prototype was developed in preparation for …

Cover Girl Run For Cover, Rénee Olander

English Faculty Publications

No abstract provided.

The Gender Revolution, Nancy Topping Bazin

Women's & Gender Studies Faculty Publications

(First paragraph) In the fall of 1958, when I arrived at Stanford University to begin a Ph.D., the all-male faculty of the English department were still grumbling in the corridors about the last woman they had hired. They had found her too assertive, so they did not want to repeat that mistake. Later, at a session on getting jobs, the department chair told us that females would be hired "at one level of university lower than what they deserved." In 1960, like the other silent students, I accepted that pattern as the way the world worked. Yet the injustice of …

An Architectural Framework For Performance Analysis: Supporting The Design, Configuration, And Control Of Dis /Hla Simulations, David B. Cavitt

Computer Science Theses & Dissertations

Technology advances are providing greater capabilities for most distributed computing environments. However, the advances in capabilities are paralleled by progressively increasing amounts of system complexity. In many instances, this complexity can lead to a lack of understanding regarding bottlenecks in run-time performance of distributed applications. This is especially true in the domain of distributed simulations where a myriad of enabling technologies are used as building blocks to provide large-scale, geographically disperse, dynamic virtual worlds. Persons responsible for the design, configuration, and control of distributed simulations need to understand the impact of decisions made regarding the allocation and use of the …

Developing A Parametric Cost Model For Operating Costs Of Army Ground Combat Weapon Systems, James O. Winbush Jr.

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research was to develop a parametric cost model for predicting operating costs of Army ground combat weapon systems. The model is intended to be used during the first two phases of the Army's acquisition process. The research necessary to develop the model was guided by two questions: what weapon system characteristics (such as weight, horsepower, fuel consumption, primary mission, NBC protection, fire control and night fighting capability) impact directly on operating ground combat systems; and what is the form of the parametric model for operating costs for ground combat systems? The study extends the bounds of …

Piezoceramic Actuator Placement For Acoustic Control Of Panels, Jeffrey S. Bevan

Mechanical & Aerospace Engineering Theses & Dissertations

Optimum placement of multiple traditional piezoceramic actuators is determined for active structural acoustic control of flat panels. The structural acoustic response is determined using acoustic radiation filters and structural surface vibration characteristics. Linear Quadratic Regulator (LQR) control is utilized to determine the optimum state feedback gain for active structural acoustic control. The optimum actuator location is determined by minimizing the structural acoustic radiated noise using a modified genetic algorithm. Experimental tests are conducted and compared to analytical results.

Anisotropic piezoceramic actuators exhibit enhanced performance when compared to traditional isotropic piezoceramic actuators. As a result of the inherent isotropy, these advanced …

Applications Of Wavelet Transforms In Biomedical Optoacoustics, Zibiao Wei, Shujun Yang, Amin N. Dharamsi, Barbara Hargrave

Biological Sciences Faculty Publications

We discuss the utility of wavelet transform methods in signal processing in general, and in particular, demonstrate the technique in optoacoustic applications. In several optoacoustic experiments with different samples, we have successfully enhanced the signal to noise ratios. Wavelet transforms optimize resolution by utilizing a tailored, variable time-window in different frequency regions. The technique's great advantage lies in the fact that the wavelet transform adds some redundancy to the original signal, and some desired features can be enhanced in the transformed space. In addition, proper choice of the basis set allows a sparse representation of the signal. Therefore, even when …

Part 3: The State Of The Regional Economy, Regional Studies Institute, Old Dominion University

State of the Region Reports: Hampton Roads

(First Paragraph) Many factors come into play when predicting the future of the Hampton Roads economy. Defense spending, non-defense-sector growth and a commitment to collaboration among private and public high-tech industries are three very large variables that contribute to the region's pulse and prospects for long-term health. All of these factors, as we will see here, are interconnected. Per capita income, often used to measure a region's economic well-being, should continue to exhibit "baseline improvement" in Hampton Roads, but if the standard of living is to rise above average, some changes would need to be made to the region's economic …

Part 8: The State Of Transportation, Regional Studies Institute, Old Dominion University

State of the Region Reports: Hampton Roads

(First Paragraph) What road do we take- literally and figuratively- to help solve our traffic congestion woes?

Part 9: The State Of The Workforce, Regional Studies Institute, Old Dominion University

State of the Region Reports: Hampton Roads

(First paragraph) Is the workforce as good (or as bad) as they say?

Soapbox: The Academic Research Fleet: An Exciting Time For Renewal, Larry Atkinson

CCPO Publications

(First Paragraph) Academic research ships in the United States are the envy of many scientists around the world. A great strength of our system is the diversity of ships and operators: users have a choice, the system can change. A weakness of the system is that very diversity: sometimes it is hard for us to act together. Nevertheless, we now must act together. The vitality of the academic fleet in the coming decades is at stake. The reason is simply because many of our ships, especially in the intermediate size range, will soon reach the end of their useful life.

Measurements Of Salinity In The Coastal Ocean: A Review Of Requirements And Technologies, Catherine Woody, Eddie Shih, Jerry Miller, Thomas Royer, Larry P. Atkinson, Richard S. Moody

CCPO Publications

Salinity, a measure of the dissolved salts in seawater, is a fundamental property of seawater and basic to understanding biological and physical processes in coastal waters. In the open ocean long term salinity measurements are identified as necessary to understand global climate studies, hydrological cycle, and circulation. In the coastal oceans, information on salinity is critical to understanding biological effects on ecosystem function such as disease, nursery grounds, or harmful algal blooms and on physical processes such as freshwater runoff estuarine mixing, and coastal currents. While the importance of salinity is recognized, little attention has been given to making routine …

Part 1: The State Of Public Opinion, Regional Studies Institute, Old Dominion University

State of the Region Reports: Hampton Roads

(First Paragraph) Would you like to see the 14 cities and counties of Hampton Roads merge into a single jurisdiction? Surprisingly, 50.5 percent of 1,169 people polled recently believe that such a merger should occur. For cities or counties where at least 20 individuals responded to this question, the percentage of those desiring a merger ranged from lows of 41.7 in Suffolk and 42.4 in James City County to highs of 54.8 percent in Gloucester County and 55.8 percent in Norfolk. The region's largest city, Virginia Beach, split evenly on this issue, with 153 respondents preferring a merger and 153 …

Part 7: The State Of Technology, Regional Studies Institute, Old Dominion University

State of the Region Reports: Hampton Roads

(First Paragraph) What will it take for us to compete in the high tech arena?

An Examination Of A Multidimensional Model Of Customer Satisfaction With Internet Purchasing, Kathleen Vanscoyoc

Theses and Dissertations in Business Administration

The World Wide Web and Internet have transformed the competitive business environment and altered the customer-firm relationship by creating a new retailing format and service enterprise. It is rapidly growing as a competitive distribution medium in which customer satisfaction will be a major success factor in the development and maintenance of this new retailing format. Despite its growing importance as a new shopping medium, little empirical research has been conducted that examines the relationship between Internet shopping, customer satisfaction, company image, and future online purchasing. Research is needed to develop theoretical models that will systematically explain and predict behavior related …

Virtual Compton Scattering In The Nucleon Resonance Region, Luminita Anca Todor

Physics Theses & Dissertations

This thesis is a study of virtual Compton scattering reaction in which a virtual photon is elastically scattered off a proton γv p → γp. The p( e,e′p)γ reaction was measured in the nucleon resonance region for the first time in the experiment E93-050 in Hall A at Thomas Jefferson National Accelerator Facility. To lowest order in ^αQED, this reaction is a coherent superposition of radiation from the incident or scattered electron in elastic ep scattering (Bethe-Heitler) and exclusive production of a photon on the proton, by absorption of a virtual photon …

Teaching Prayer: Pilot Survey Of Academic Courses On Personal Prayer, E. James Baesler

Communication & Theatre Arts Faculty Publications

The practical concerns of an individual interested in learning about prayer in an academic context are interconnected with the practical concerns about teaching an academic course on prayer. A pilot study proposed to investigate and evaluate the context and content of academic courses on personal prayer from the perspective of teaching prayer, asking what proportion of institutions of higher education offer courses on prayer, in which department, and on what level. The search was limited to the Christian faith, and in particular to private colleges and universities of the Catholic denomination. An online Internet search yielded a sample of 126 …

An Empirical Analysis Of The Critical Determinants Affecting Commitment And Performance Of The U. S. Firm In The South African Market: Apartheid Versus Post-Apartheid, Sonja Pollard Mitchell

Theses and Dissertations in Business Administration

Recognized by the U.S. Chamber of Commerce as one of the world's Big Emerging Markets (BEMs), South Africa has received vast attention from potential foreign investors (IRRC 1994) and has been recognized by scholars as an excellent base for research (Hofmeyr, Templer and Beaty 1994). Unfortunately, little is known about the export behavior of the foreign firm in South Africa (Calof and Viviers 1995) given the country's history of political, social and economic instability.

This dissertation is an effort to increase the understanding of the factors that contribute to the commitment and overall market performance of U.S. firms in South …

New Buffer Layers, Large Band Gap Ternary Compounds: Cualte², K. Benchouk, E. Benseddik, C. O. El Moctar, J. C. Bernède, S. Marsillac, J. Pouzet, A Khellil

Electrical & Computer Engineering Faculty Publications

After deposition, by evaporation under vacuum, of Al/Cu/Te, multilayer structures, annealing at 673 K or more for half an hour, under argon flow, allows CuAlTe2 films crystallized in the chalcopyrite structure to be obtained. The optical and electrical properties are interpreted by introducing the influence of impurity foreign phases present in the films. The optical properties are sensitive to the small Al2O3 domains randomly distributed into the CuAlTe2 polycrystalline matrix. The optical band gap is slightly increased (2.35 eV) by the presence of alumina. The conductivity measurements show that a short circuit effect can be induced by a binary Cu2-xTe …

Detection And Modeling Of Radiation Induced Effects In Tissues By Dielectric Spectroscopy, Dorin A. Todor

Physics Theses & Dissertations

The work presented here is applied physics research in the field of radiation treatment. We address the development of a new and innovative method, in vivo and possibly non-invasive, for tumor and healthy tissues control during and after the radiation treatment. The radiation treatment is delivered in an almost standardized manner for particular classes of tumors. The large variance in the individual radio sensitivity of healthy tissues and tumors often leads to local recurrence of neoplastic growth and/or distant metastatic disease which often remains untreated. The method is based on the measurement and analysis of electrical impedance data in …

Toward A Model Of Team Situation Awareness, Alexis Anne Fink

Psychology Theses & Dissertations

Situation Awareness (SA) is a construct that is considered important to safety in dynamic, risky, time-constrained and complex environments, such as military aviation, nuclear reactors and emergency management. Research consideration of SA is complicated by the fact that there is no clearly superior methodology for SA measurement. Typically, SA is considered at the individual level; however, the nature of the SA context often requires more than one individual for safe and effective operations. Team SA is a qualitatively different phenomenon than individual SA. Few models of team SA have been proposed. The primary purpose of this paper was to develop …

Multicast Services For Multimedia Collaborative Applications, Emad Eldin Mohamed Mohamed

Computer Science Theses & Dissertations

This work aims at providing multicast services for multimedia collaborative applications over large inter-networks such as the Internet. Multimedia collaborative applications are typically of small group size, slow group membership dynamics, and awareness of participants' identities and locations. Moreover, they usually consist of several components such as audio, video, shared whiteboard, and single user application sharing engines that collectively help make the collaboration session successful. Each of these components has its demands from the communication layer that may differ from one component to another. This dissertation identifies the overall characteristics of multimedia collaborative applications and their individual components. It also …

Extending Traditional Static Analysis Techniques To Support Development, Testing And Maintenance Of Component-Based Solutions, Robert David Cherinka

Computer Science Theses & Dissertations

Traditional static code analysis encompasses a mature set of techniques for helping understand and optimize programs, such as dead code elimination, program slicing, and partial evaluation (code specialization). It is well understood that compared to other program analysis techniques (e.g., dynamic analysis), static analysis techniques do a reasonable job for the cost associated with implementing them. Industry and government are moving away from more ‘traditional’ development approaches towards component-based approaches as ‘the norm.’ Component-based applications most often comprise a collection of distributed object-oriented components such as forms, code snippets, reports, modules, databases, objects, containers, and the like. These components are …

Effects Of Ventilation On Human Thermal Comfort In Rooms, Ahmed F. Alfahaid

Mechanical & Aerospace Engineering Theses & Dissertations

Nowadays, the majority of people spend up to 90% of their time indoors; as a result, the maintenance of optimal indoor climate conditions has become important for their overall health and comfort. The main goal of this study is to predict numerically the flow and temperature patterns and the human thermal comfort conditions in an indoor environment using displacement ventilation.

A Computational Fluid Dynamics (CFD) code has been used to analyze thermal comfort conditions for a fullscale ventilated room. Unstructured grids have been used to discretize the numerical domain. Before undertaking a detailed investigation, the code was validated by comparing …