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1998

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A Decision Theoretic Approach For Interface Agent Development, Scott M. Brown Sep 1998

A Decision Theoretic Approach For Interface Agent Development, Scott M. Brown

Theses and Dissertations

The complexity of current software applications is overwhelming users. The need exists for intelligent interface agents to address the problem of increasing taskload that is overwhelming the human user. Interface agents could help alleviate user taskload by extracting and analyzing relevant information, and providing information abstractions of that information, and providing timely, beneficial assistance to users. These agents could communicate with the user through the existing user interface and also adapt to user needs and behaviors. Central to providing assistance to a user is the issue of correctly determining the user's intent. This dissertation presents an effective, efficient, and extensible …


Radial Complexity Estimation For Improved Generalization In Artificial Neural Networks, Lemuel R. Myers Jr. Sep 1998

Radial Complexity Estimation For Improved Generalization In Artificial Neural Networks, Lemuel R. Myers Jr.

Theses and Dissertations

When training an artificial neural network (ANN) for classification using backpropagation of error, the weights are usually updated by minimizing the sum-squared error on the training set. As training ensues, overtraining may be observed as the network begins to memorize the training data. This occurs because, as the magnitude of the weight vector, W, grows, the decision boundaries become overly complex in much the same way as a too-high order polynomial approximation can overfit a data set in a regression problem. Since w grows during standard backpropagation, it is important to initialize the weights with consideration to the importance of …


Optimal Atmospheric Compensation For Anisoplanatism In Adaptive-Optical Systems, Matthew R. Whiteley Sep 1998

Optimal Atmospheric Compensation For Anisoplanatism In Adaptive-Optical Systems, Matthew R. Whiteley

Theses and Dissertations

Anisoplanatism in adaptive optics (AO) systems is a performance-degrading effect that arises whenever light from the wave-front sensor beacon and light from the object of interest sample different volumes of optical turbulence. This effect occurs if there is either a spatial separation between the object and the beacon, or a spatial separation between the wave-front sensor and phase-compensation aperture, or if both types of separation are present in the AO system. Anisoplanatism results in an increased value of the aperture-averaged residual phase variance after AO compensation, which causes an exponential decrease in system performance. This dissertation offers a theoretical framework …


Automatic Target Cueing Of Hyperspectral Image Data, Terry A. Wilson Sep 1998

Automatic Target Cueing Of Hyperspectral Image Data, Terry A. Wilson

Theses and Dissertations

Modern imaging sensors produce vast amounts data, overwhelming human analysts. One such sensor is the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) hyperspectral sensor. The AVIRIS sensor simultaneously collects data in 224 spectral bands that range from 0.4µm to 2.5µm in approximately 10nm increments, producing 224 images, each representing a single spectral band. Autonomous systems are required that can fuse "important" spectral bands and then classify regions of interest if all of this data is to be exploited. This dissertation presents a comprehensive solution that consists of a new physiologically motivated fusion algorithm and a novel Bayes optimal self-architecting classifier …


The Effects Of Three Media Presentation Systems On Maintenance Task Performance, John W. Chastain Sep 1998

The Effects Of Three Media Presentation Systems On Maintenance Task Performance, John W. Chastain

Theses and Dissertations

Wearable computers and Portable Maintenance Aids (PMAs) may soon be the normal way of doing aircraft maintenance in the Air Force. Currently, the Air Force uses the paper form of Technical Orders (TO's) while doing aircraft maintenance. The purpose of this thesis was to compare the effects of three different media presentations of the information used during aircraft maintenance. The three different presentations compared are the current paper form, a Head Mounted Display (HMD), and an auditory mode. An experiment was conducted to determine if there was a significant difference between the systems (in terms of task completion times and …


Production And Propagation Of Hermite–Sinusoidal-Gaussian Laser Beams, Lee W. Casperson, Anthony A. Tovar Sep 1998

Production And Propagation Of Hermite–Sinusoidal-Gaussian Laser Beams, Lee W. Casperson, Anthony A. Tovar

Electrical and Computer Engineering Faculty Publications and Presentations

Hermite–sinusoidal-Gaussian solutions to the wave equation have recently been obtained. In the limit of large Hermite–Gaussian beam size, the sinusoidal factors are dominant and reduce to the conventional modes of a rectangular waveguide. In the opposite limit the beams reduce to the familiar Hermite–Gaussian form. The propagation of these beams is examined in detail, and resonators are designed that will produce them. As an example, a special resonator is designed to produce hyperbolic-sine-Gaussian beams. This ring resonator contains a hyperbolic-cosine-Gaussian apodized aperture. The beam mode has finite energy and is perturbation stable.


Construction Of Effective Electromagnetic Currents For Two-Body Quasipotential Equations, Dmitri Krioukov Sep 1998

Construction Of Effective Electromagnetic Currents For Two-Body Quasipotential Equations, Dmitri Krioukov

Physics Theses & Dissertations

A systematic algebraic approach for the construction of effective electro-magnetic currents consistent with relativistic two-body quasipotential equations is presented. This approach generalizes the Mandelstam formalism and applies it to a generic quasipotential reduction method. The use of Ward-Takahashi identities for the effective currents guarantees conservation of current matrix elements involving any combination of bound and scattering states. This approach is shown to reproduce previous results for current matrix elements for the particular cases of the Gross and Blankenbecler-Sugar equations. A generic method of truncation of the quasipotential effective current with respect to the number of boson exchanges is introduced.


Bubble Fractionation Of Enantiomers From Solution Using Molecularly Imprinted Polymers As Collectors, Daniel W. Armstrong, J. M. Schneiderheinze, Y. S. Hwang, B. Sellergren Sep 1998

Bubble Fractionation Of Enantiomers From Solution Using Molecularly Imprinted Polymers As Collectors, Daniel W. Armstrong, J. M. Schneiderheinze, Y. S. Hwang, B. Sellergren

Chemistry Faculty Research & Creative Works

Adsorptive bubble separation methods have been used to enrich components from both heterogeneous and homogeneous solutions. These methods are particularly effective for processing large solution volumes at low cost Previous work demonstrated that chiral, surface-active collectors could be used to enrich enantiomers from homogeneous solution in a foam fractionation process. In a significant extension of this work, the use of highly selective molecularly imprinted polymers (MIPs) and heterogeneous solutions for the bubble flotation of enantiomers was evaluated. The high selectivity and ease of recycling of the MIP make this a potentially powerful approach for process-scale separations from large-volume bulk solutions. …


The Feasibility Of Launching Small Satellites With A Light Gas Gun, H. Gilreath, A. Driesman, W. Kroshl, M. White, H. Cartland, J. Hunter Aug 1998

The Feasibility Of Launching Small Satellites With A Light Gas Gun, H. Gilreath, A. Driesman, W. Kroshl, M. White, H. Cartland, J. Hunter

Small Satellite Conference

This paper summarizes a study conducted for the Defense Advanced Research Projects Agency of the technical and economic feasibility of using a light gas gun to launch small satellites. The launcher concept is based upon a distributed-injection gun, which, in principle, can produce high muzzle velocities at relatively low acceleration levels. To establish initial system requirements for the launcher and spacecraft, the deployment of a large constellation of telecommunications satellites is chosen as a reference mission. This choice reflects the dominance of telecommunications in current commercial LEO market projections, but the results obtained for this mission are later generalized to …


Jswitch/Jsat: Real-Time And Offiine World Wide Web Interface, Abigail Maury, Anna Critchfield, Jim Langston, Cynthia Adams Aug 1998

Jswitch/Jsat: Real-Time And Offiine World Wide Web Interface, Abigail Maury, Anna Critchfield, Jim Langston, Cynthia Adams

Small Satellite Conference

The Java-based spacecraft web interface to telemetry and command handling, Jswitch, is a prototype, platform-independent user interface to a spacecraft command and control system that uses Java technology, readily available security software, standard World Wide Web protocols, and commercial off-the-shelf (COTS) products. The Java-based science analysis and trending tool, Jsat, is a major element in Jswitch. Jsat is an inexpensive, Web-based, information-on-demand science data trend analysis tool. Both Jswitch and Jsat were developed in Java for NASA's Goddard Space Flight Center (GSFC). Jsat provides Web interface user access to science data from different satellites. Historically, satellite science data trend analysis …


The Implementation Of Satellite Attitude Control System Software Using Object Oriented Design , Mark Reid, William Hansell, Tom Phillips Aug 1998

The Implementation Of Satellite Attitude Control System Software Using Object Oriented Design , Mark Reid, William Hansell, Tom Phillips

Small Satellite Conference

NASA established the Small Explorer (SMEX) program in 1988 to provide frequent opportunities for highly focused and relatively inexpensive space science missions. The SMEX program has produced five satellites, three of which have been successfully launched. The remaining two spacecraft are scheduled for launch within the coming year. NASA has recently developed a prototype for the next generation Small Explorer spacecraft (SMEX-Lite). This paper describes the object-oriented design (OOD) of the SMEX-Lite Attitude Control System (ACS) software. The SMEX-Lite ACS is three-axis controlled and is capable of performing sub-arcminute pointing. This paper first describes high level requirements governing the SMEX-Lite …


On Campus, August 31, 1998, Coastal Carolina University Aug 1998

On Campus, August 31, 1998, Coastal Carolina University

On Campus Newsletter

A Newsletter for Faculty and Staff of Coastal Carolina University. Volume 8, Number 13


A Resource Allocation Mechanism Based On Cost Function Synthesis In Complex Systems, Carlos C. Amaro Aug 1998

A Resource Allocation Mechanism Based On Cost Function Synthesis In Complex Systems, Carlos C. Amaro

Dissertations

While the management of resources in computer systems can greatly impact the usefulness and integrity of the system, finding an optimal solution to the management problem is unfortunately NP hard. Adding to the complexity, today's 'modern' systems - such as in multimedia, medical, and military systems - may be, and often are, comprised of interacting real and non-real-time components. In addition, these systems can be driven by a host of non-functional objectives – often differing not only in nature, importance, and form, but also in dimensional units and range, and themselves interacting in complex ways. We refer to systems exhibiting …


Microwave Heating Of Fluid/Solid Layers : A Study Of Hydrodynamic Stability And Melting Front Propagation, John Gilchrist Aug 1998

Microwave Heating Of Fluid/Solid Layers : A Study Of Hydrodynamic Stability And Melting Front Propagation, John Gilchrist

Dissertations

In this work we study the effects of externally induced heating on the dynamics of fluid layers, and materials composed of two phases separated by a thermally driven moving front. One novel aspect of our study is in the nature of the external source, which is provided by the action of microwaves acting on dielectric materials. The main challenge is to model and solve systems of differential equations, which couple fluid dynamical motions (the Navie- Stokes equations for nonisothermal flows) and electromagnetic wave propagation (governed by Maxwell's equations).

When an electromagnetic wave impinges on a material, energy is generated within …


Emissivity Measurements And Modeling Of Silicon Related Materials And Structures, Sufian Abedrabbo Aug 1998

Emissivity Measurements And Modeling Of Silicon Related Materials And Structures, Sufian Abedrabbo

Dissertations

The objective of this dissertation is to investigate the major issues concerning applications of pyrometry for applications in rapid thermal processing (RTP) of silicon related materials. The research highlights of this work are:

Establishment of spectral ernissometry as a novel, reliable and reproducible technique for:

Determination of wavelength and temperature dependent reflectivity, transmissivity, emissivity and temperature, simultaneously, of silicon related materials and structures. The emissometer operates in the wavelength range of 1-20mm and temperature range of 300-1200K. The analysis of the influence of morphological effects on the radiative properties by measurement of (a) front-smooth incidence versus backside-rough incidence of singleside …


A Folder Organization Model For Information Systems : Exploring Its Architectural Expressive Power And Predicate-Based Filing, Simon Doong Aug 1998

A Folder Organization Model For Information Systems : Exploring Its Architectural Expressive Power And Predicate-Based Filing, Simon Doong

Dissertations

This dissertation presents an Internal Folder Organization (I-ORG) which supplements the architectural deficiencies of the existing model - the User Folder Organization (U-ORG), to electronically model a person's filing system in the modern office environment. An I-ORG folder organization gives a logical representation of how documents of the same or different kinds are related and grouped into folders based on predefined premises. Our model is represented by a Rooted Direct Acyclic Graph (RDAG). Each node in the graph represents a folder; and folders are related by "subfolder relationship" (for capturing the "and" relation) and "virtual-folder relationship" (for capturing the "or" …


A Graph Based Process Model Measurement Framework Using Scheduling Theory, Gary Guang-Li Mou Aug 1998

A Graph Based Process Model Measurement Framework Using Scheduling Theory, Gary Guang-Li Mou

Dissertations

Software development processes, as a means of ensuring software quality and productivity, have been widely accepted within the software development community; software process modeling, on the other hand, continues to be a subject of interest in the research community. Even with organizations that have achieved higher SEI maturity levels, processes are by and large described in documents and reinforced as guidelines or laws governing software development activities. The lack of industry-wide adaptation of software process modeling as part of development activities can be attributed to two major reasons: lack of forecast power in the (software) process modeling and lack of …


Pneumatic Fracture Propagation And Particulate Transport In Geologic Formations, Suresh Puppala Aug 1998

Pneumatic Fracture Propagation And Particulate Transport In Geologic Formations, Suresh Puppala

Dissertations

Pneumatic fracturing is an in situ remediation enhancement technology developed to increase the permeability of contaminated geologic formations. This technology can also be used to deliver atomized liquid and particulate supplements to geologic formations, thereby enhancing in situ processes such as bioremediation and reactive dechlorination.

The main objective of this study was the development of a mathematical model that simulates the propagation of pneumatic fractures in soil and rock formations. Pneumatic fracture propagation differs from other fluid fracturing phenomena in the propagation velocity (1-3 m/sec) and the viscosity of the fracturing fluid (1.9E-05 Pa•sec). For the purposes of model development, …


Automatic Analysis Of Electronic Drawings Using Neural Network, Yi Shi Aug 1998

Automatic Analysis Of Electronic Drawings Using Neural Network, Yi Shi

Dissertations

Neural network technique has been found to be a powerful tool in pattern recognition. It captures associations or discovers regularities with a set of patterns, where the types, number of variables or diversity of the data are very great, the relationships between variables are vaguely understood, or the relationships are difficult to describe adequately with conventional approaches.

In this dissertation, which is related to the research and the system design aiming at recognizing the digital gate symbols and characters in electronic drawings, we have proposed: (1) A modified Kohonen neural network with a shift-invariant capability in pattern recognition; (2) An …


Adaptive Bootstrap Signal Separators For Bpsk/Qam-Modulated Wireless Cdma Systems In A Multipath Environment, Nico J.M. Van Waes Aug 1998

Adaptive Bootstrap Signal Separators For Bpsk/Qam-Modulated Wireless Cdma Systems In A Multipath Environment, Nico J.M. Van Waes

Dissertations

CDMA is an attractive multiple-access scheme, because of its potential capacity increase and its anti-multipath fading capability. For satisfactory performance, however, the effect of the "near-far" problem has to be resolved. This problem can be combated by using power-control, which, however, results in an overall reduction in communication ranges, and thus in a loss of capacity. Among other methods for mitigating the near-far problem is the use of decorrelating receivers, both of fixed type, which directly utilizes the cross-correlation of the users codes, and of adaptive type, which uses recursive algorithms that leads to signal decorrelation. Not to lessen the …


Univercity News (1998-08-31) Aug 1998

Univercity News (1998-08-31)

UniverCity News, 1998-2001

VCU Today, the University’s first official administrative organ, began as a somewhat irregular monthly publication but moved to a bi-weekly newspaper format in the 1980s. The newspaper changed its name to VCU Voice in 1988 and ten years later it appeared under the title UniverCity News. As it neared the end of its run as a physical newspaper, the publication became simply VCU News. These four publications were essentially the same periodical published under different titles by the Office of University Relations. VCU News appeared online for the first time in 2002.


Hexapod Herald - Vol. 10, No. 7, August 31, 1998 Aug 1998

Hexapod Herald - Vol. 10, No. 7, August 31, 1998

Hexapod Herald and Other Entomology Department Newsletters

Faculty news

Staff news

Graduate student news

Publications

From Cheri's desk

Classes offered this semester

Calendar of events

State of Nebraska travel reimbursement requirements


Current Unrestricted Operating Budgets, Fiscal Year 1999, University Of Montana--Missoula. Office Of Administration And Finance Aug 1998

Current Unrestricted Operating Budgets, Fiscal Year 1999, University Of Montana--Missoula. Office Of Administration And Finance

University of Montana Current Unrestricted Operating Budgets, 1993-2017

The unrestricted operating budget of the University of Montana, issued by the Office of University Planning, Budgeting and Analysis under the Office of Administration and Finance.


August 31, 1998 Reporter, University Of Alabama At Birmingham Aug 1998

August 31, 1998 Reporter, University Of Alabama At Birmingham

eReporter (campus newsletter)

No abstract provided.


Daily Eastern News: August 31, 1998, Eastern Illinois University Aug 1998

Daily Eastern News: August 31, 1998, Eastern Illinois University

August

No abstract provided.


Observation Of High Momentum Η′ Production In B Decays, T. E. Browder, Kenneth A. Bloom, Cleo Collaboration Aug 1998

Observation Of High Momentum Η′ Production In B Decays, T. E. Browder, Kenneth A. Bloom, Cleo Collaboration

Kenneth Bloom Publications

We report the first observation of B→ η′X transitions with high momentum η′ mesons. We observe 39.0 ± 11.6 B decay events with 2.0 < Pη′ < 2.7 GeV/c, the high momentum region where background from b → c processes is suppressed. We discuss the physical interpretation of the signal, including the possibility that it is due to b → sg* transitions. Given that interpretation, we find Ɓ(B →η′Xs) = [6.2 ± 1.6(stat) ± 1.3(syst) -1.5+0.0(bkg)] X 10-4 for 2.0 < Pη′ < 2.7 GeV/c.


Grand Valley Forum, Volume 023, Number 05, August 31, 1998, Grand Valley State University Aug 1998

Grand Valley Forum, Volume 023, Number 05, August 31, 1998, Grand Valley State University

1998-1999, Volume 23

Grand Valley Forum is Grand Valley State's faculty and staff newsletter, published from 1976 to the present.


Analysis And Applications Of Ftir Systems, Gunjan Navin Doshi Aug 1998

Analysis And Applications Of Ftir Systems, Gunjan Navin Doshi

Theses

Fourier Transform Infrared Spectroscopy (FTIR) is a dynamical instrumental technique used in industry for measuring high quality infrared spectra. Over the last 25 years, the increased demand for having an efficient real-time quantitative measurement technique has led to extensive research and development in the field of FTIR Spectroscopy. Through the use of FTIR, sensitivity has increased, size of the smallest sample that can be analyzed has been reduced, and the number of new applications has exploded. In this thesis, an attempt is made to study the principles, theory, instrumentation and applications of FTIR Spectrometry. We survey the working of spectrometer, …


Improving The Run Time Of The Decomposition Algorithm For Fault Tolerant Clos Interconnection Networks Through Swap Re-Ordering, Andrea Laura Mcmakin Aug 1998

Improving The Run Time Of The Decomposition Algorithm For Fault Tolerant Clos Interconnection Networks Through Swap Re-Ordering, Andrea Laura Mcmakin

Theses

Clos interconnection networks, used in data networks and computing systems, can contain extra switches to be used in faulty conditions. The speed of such fault tolerant Clos interconnection networks is improved through the use these switches in no-fault situations. The network can be represented by a matrix, which is then decomposed using an algorithm, and the switch settings are thus assigned.

The original decomposition algorithm consisted of four element swaps in the following order: wild swap, simple swap, next simple swap, and successive swap. However, by re-arranging these swaps with the simple swap first, followed by the next simple and …


Competition Of Copper, Lead, And Cadmium Adsorption To Goethite, Chris A. Christophi Aug 1998

Competition Of Copper, Lead, And Cadmium Adsorption To Goethite, Chris A. Christophi

Theses

Competition of copper, lead, and cadmium adsorption on goethite depends on metal ion and oxide surface characteristics. Goethite was characterized via X-ray diffraction, potentiometric titrations, site density determination, particle size analysis, and optical microscopy. In this thesis, a hypothesis was tested that electronegativity is the most important factor in metal affinities and adsorption competition to goethite.

Metal affinity and site density for the goethite surface were assessed by performing adsorption edges and isotherms. Based on the results of these experiments, competition studies were designed to observe adsorption and displacement of the competing metals by limiting the number of available sites …