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1997

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The Season - Summer: 1 June - 31 July 1997, Richard L. Knight, Martha G. Waldron, Francis C. Fekel, Richard P. Lewis Dec 1997

The Season - Summer: 1 June - 31 July 1997, Richard L. Knight, Martha G. Waldron, Francis C. Fekel, Richard P. Lewis

The Migrant - Tennessee Ornithological Society

No abstract provided.

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Puncturing Ability Of Bat Canine Teeth: The Tip, Patricia W. Freeman, William N. Weins Dec 1997

Puncturing Ability Of Bat Canine Teeth: The Tip, Patricia W. Freeman, William N. Weins

University of Nebraska State Museum: Mammalogy Papers

Casts of upper canine teeth of 15 species of microchiropteran bats were fixed securely into a testing machine and made to puncture the bloom side of an apple. The force necessary to break through the surface of the apple was regressed against both shape of the tip of the canine and the size of the animal. Sharper tips require less force to puncture than blunt ones. Results were also verified using giant two-dimensional models of Plexiglas™ with sharp and blunt tips that were loaded onto a Plexiglas™ beam. Fringes, or stress lines, are more highly concentrated at the point of …

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Water Current, Volume 29, No. 6, December 1997 Dec 1997

Water Current, Volume 29, No. 6, December 1997

Water Current Newsletter

New Equipment Enhances Water Sciences Laboratory's Research Capabilities
From the Director: USGS/NIWR Cooperation, Joint Programming Increasing; NRI Budget Reductions
27th Water Conference Begins Three-Year Look at "Nebraska Water 2000"
Annual Seminar to Examine Interrelationship of Water, Native Grasslands and Wetlands
Pesticide Container Recycling Hits Six Year Peak
Audubon Launches State Office
Environmental Decision Making Conference
MidAmerica GIS Symposium Comes to Cornhusker Hotel in May
Symposium Proceedings Available from Great Plains Foundation
Water News Briefs
Tips on Water Conservation
Useful Resources
Source Water Protection Conference Coming to Dallas in April
UNL Faculty Bring Home ASAE Educational Blue Ribbons

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Sex Selection Abortion And The Boomerang Effect Of A Woman's Right To Choose: A Paradox Of The Skeptics, Lynne Marie Kohm Dec 1997

Sex Selection Abortion And The Boomerang Effect Of A Woman's Right To Choose: A Paradox Of The Skeptics, Lynne Marie Kohm

William & Mary Journal of Race, Gender, and Social Justice

No abstract provided.

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Investigation Of Two-Phase Air Water Flow Using Annubar, Ehab Fouad Shoukry Dec 1997

Investigation Of Two-Phase Air Water Flow Using Annubar, Ehab Fouad Shoukry

Archived Theses and Dissertations

No abstract provided.

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The Effect Of Data Model, System And Task Characteristics On User Query Performance – An Empirical Study, Hock Chan, Keng Siau, Kwok-Kee Wei Dec 1997

The Effect Of Data Model, System And Task Characteristics On User Query Performance – An Empirical Study, Hock Chan, Keng Siau, Kwok-Kee Wei

Research Collection School Of Computing and Information Systems

With the proliferation of end-user computing and empowerment of end users in the organizations, the user-database interface is increasingly being recognized as an important research area. A user-database interface consists of two key components: the data model and the query language. Database management system designers can manipulate these two components to produce an effective database interface to maximize user task performance. However, in order to do this, the designers first need to know the effect of the two components on end users and the interaction effect of the two components. Despite the acknowledgment of user-database interface as a cornerstone in …

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…Of Cabbages And Kings. December, 1997, Emeriti Society, University Of The Pacific Dec 1997

…Of Cabbages And Kings. December, 1997, Emeriti Society, University Of The Pacific

Emeriti Newsletter: "...Of Cabbages and Kings"

"...Of Cabbages and Kings" is the newsletter of the University of the Pacific Emeriti Society. Read more about the Emeriti Society of Pacific by clicking here.

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Design Research: The Newsletter Of The Design Research Society No.59, Stephen Little Dec 1997

Design Research: The Newsletter Of The Design Research Society No.59, Stephen Little

Design Research Newsletters (1966-1999)

No abstract provided.

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Sinusoidal-Gaussian Beams In Complex Optical Systems, Lee W. Casperson, Dennis G. Hall, Anthony A. Tovar Dec 1997

Sinusoidal-Gaussian Beams In Complex Optical Systems, Lee W. Casperson, Dennis G. Hall, Anthony A. Tovar

Electrical and Computer Engineering Faculty Publications and Presentations

Sinusoidal-Gaussian beam solutions are derived for the propagation of electromagnetic waves in free space and in media having at most quadratic transverse variations of the index of refraction and the gain or loss. The resulting expressions are also valid for propagation through other real and complex lens elements and systems that can be represented in terms of complex beam matrices. The solutions are in the form of sinusoidal functions of complex argument times a conventional Gaussian beam factor. In the limit of large Gaussian beam size, the sine and cosine factors of the beams are dominant and reduce to the …

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Linear-Strip Photographs Using Cirkut And Hulcher Cameras, Andrew Davidhazy Dec 1997

Linear-Strip Photographs Using Cirkut And Hulcher Cameras, Andrew Davidhazy

Articles

This article describes the process by which cameras originally designed for use as rotating, 360 degree coverage, panoramic cameras can be used for applications such as photographing the full length of a passing train or the facades of all the buildings along a street.

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An Examination Of Elements Necessary For Transfer Of An Environmental Remediation Technology From Full-Scale Demonstration To Implementation, Glenn C. Mandalas Dec 1997

An Examination Of Elements Necessary For Transfer Of An Environmental Remediation Technology From Full-Scale Demonstration To Implementation, Glenn C. Mandalas

Theses and Dissertations

The fact that an innovative environmental remediation technology has been proven feasible in a full scale evaluation does not assure that the technology will be implemented. A number of regulatory, economic, and institutional barriers may impede the transition of a remediation technology from full scale demonstration to implementation. This research explores these barriers, suggesting means to overcome them. Regulators, technology users, and other remediation decision makers apply the nine criteria specified in the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) to evaluate the applicability of an innovative remediation technology at uncontrolled hazardous waste sites. These criteria consider such things …

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Metabolic Inhibition Of A Toluene-Enriched Microbial Population Due To Lead (Pb2+): Verification Of A Free Metal Ion Toxicity Model, Patrick J. S. Marbas Dec 1997

Metabolic Inhibition Of A Toluene-Enriched Microbial Population Due To Lead (Pb2+): Verification Of A Free Metal Ion Toxicity Model, Patrick J. S. Marbas

Theses and Dissertations

A dissolved oxygen probe and an ion specific electrode were used to study the lead-induced metabolic inhibition in a toluene-enriched microbial population. Predicted toxicity values were compared to the actual toxicity responses using a free metal ion toxicity model (TM) which linked metabolic inhibition with lead activity. Experimentally derived values for the model parameters (lead activity and a lead distribution coefficient) were used in the TM. It was postulated that cellular metabolism is disrupted by the conformational changes to the cell's plasma membrane produced by lead ion adsorption. The predicted toxicity values were higher than the actual toxicity response. This …

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A Reconfigurable Superscalar Architecture, Christopher B. Mayer Dec 1997

A Reconfigurable Superscalar Architecture, Christopher B. Mayer

Theses and Dissertations

The invention of the Field Programmable Gate Array (FPGA) has led to a number of interesting developments. One is the idea of providing custom hardware support for applications running on a computer. These reconfigurable computers have been shown to decrease the execution time for some applications. Based on past results, attention has subsequently turned to using reconfigurable computing in general-purpose computers (e.g. desktop and workstation environments). This thesis develops a design for just such a computer. The design, FPGADLX, is based on a hypothetical superscalar computer running the DLX instruction set and is generic enough in principle to be adapted …

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Flow Field And Loading Analysis On A Wrap-Around Fin Missile, Thomas C. Mcintyre Dec 1997

Flow Field And Loading Analysis On A Wrap-Around Fin Missile, Thomas C. Mcintyre

Theses and Dissertations

Wrap-around fin (WAF) missiles offer packaging benefits but experience rolling moments due to the curved fin design. Rolling moments stabilize unguided projectiles, but cause guidance and control problems for future guided applications. Understanding the flow field in the vicinity of the fins is critical to future missiles. Fin pressure profiles were characterized with pressure-sensitive paint. Two rectangular four-fin constructions were tested-one solid and one with a rectangular hole (slotted fin). Static pressure data were divided by free-stream total pressure for presentation. Tests were conducted at Mach numbers of 2.15, 2.28, 2.41, 2.86, 3.25, 3.50 and 3.83. Reynolds numbers based on …

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Using Cross-Eye Techniques To Counter Radio Frequency Agile Monopulse Processing, Gregory J. Meyer Dec 1997

Using Cross-Eye Techniques To Counter Radio Frequency Agile Monopulse Processing, Gregory J. Meyer

Theses and Dissertations

The purpose of this research was to evaluate how current cross-eye techniques protect an airborne platform versus a pulse-to-pulse Radio Frequency (RF) agile monopulse processing threat and, if necessary, develop a new cross-eye techniques to counter this threat. This research evaluates how both current retrodirective cross-eye techniques and an original technique, namely synchronized cross-eye, hide the true skin return in the time and frequency domain while preserving the necessary phase interferometric effects at the threat radar location. Existing retrodirective cross-eye techniques are inadequate to counter the RF agile threat due to propagation delays. Using modeling and simulation, the research shows …

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Atmospheric Induced Errors In Space-Time Adaptive Processing, Vinod D. Naga Dec 1997

Atmospheric Induced Errors In Space-Time Adaptive Processing, Vinod D. Naga

Theses and Dissertations

This thesis examines the effects of atmospheric turbulence-induced phase perturbations on the performance of ground-based Space-Time Adaptive Processing (STAP) systems. Both Fully Adaptive Joint Domain Optimum and Partially Adaptive Factored-Time Space processing methods are examined. This thesis concentrates on the turbulence effects on STAP applied to ground-based arrays. This thesis further focuses on the capability of STAP to resolve targets at low elevation angles in the presence of turbulence. Only clutter interference and receiver noise are considered. Turbulence effects on the EM phase-front are calculated for turbulence strength Cn(2) values ranging from 5.0 x 10-14 m-2/3 to 5.0 …

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Assessment Of Customer Perceptions Of The Hazardous Materials Pharmacy, Sean M. O'Brien Dec 1997

Assessment Of Customer Perceptions Of The Hazardous Materials Pharmacy, Sean M. O'Brien

Theses and Dissertations

The Air Force began operations of a Hazardous Material Pharmacy (HMP) in the late 80s. This thesis identifies causes of positive and negative perceptions of the HMP among its customers. Focus groups were used to determine customer perceptions. Several Total Quality Management (TQM) tools were used in this analysis. Brainstorming was used to generate customer perceptions. Affinity diagrams were used to group data into meaningful categories. Interrelationship digraphs were used to determine influence among causes of perception and to rank the causes of perception. This study showed that lack of clear policy and support of the HMP were the leading …

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Reduced Computational Cost, Totally Symmetric Angular Quadrature Sets For Discrete Ordinates Radiation Transport, Joseph M. Oder Dec 1997

Reduced Computational Cost, Totally Symmetric Angular Quadrature Sets For Discrete Ordinates Radiation Transport, Joseph M. Oder

Theses and Dissertations

Several new quadrature sets for use in the discrete ordinates method of solving the Boltzmann neutral particle transport equation are derived. These symmetric quadratures extend the traditional symmetric quadratures by allowing ordinates perpendicular to one or two of the coordinate axes. Comparable accuracy with fewer required ordinates is obtained. Quadratures up to seventh order are presented. The validity and efficiency of the quadratures is then tested and compared with the Sn level symmetric quadratures relative to a Monte Carlo benchmark solution. The criteria for comparison include current through the surface, scalar flux at the surface, volume average scalar flux, and …

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Displacement Of The Earth's Bow Shock And Magnetopause Due To An Impinging Interplanetary Shock Wave, William A. Olson Dec 1997

Displacement Of The Earth's Bow Shock And Magnetopause Due To An Impinging Interplanetary Shock Wave, William A. Olson

Theses and Dissertations

Interplanetary shock waves (ISWs) propagating through the solar wind can collide with the earth's bow shock, resulting in a series of new shocks, contact discontinuities, and rarefaction waves which interact to effectively move the bow shock and magnetopause toward the earth. A one dimensional MacCormack predictor corrector algorithm with Flux Corrected Transport (FCT) was developed to model the ISW bow shock and magnetopause interactions, and to numerically predict their propagation speeds after collision. Analytic relationships for the Mach numbers and propagation speeds of the generated shock waves and contact discontinuities were used to validate the model and to compare numerical …

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Cepstral Processing For Gps Multipath Detection And Mitigation, Charles D. Ormsby Dec 1997

Cepstral Processing For Gps Multipath Detection And Mitigation, Charles D. Ormsby

Theses and Dissertations

This work presents a novel approach to code phase multipath mitigation for Global Positioning System (GPS) receivers. It uses the power and complex cepstra for multipath detection and mitigation prior to code phase tracking by a standard non-coherent delay lock loop. Cepstral theory is presented to demonstrate how multipath reflection delays can be detected through the use of the power cepstrum. Filtering can then be performed on the complex cepstrum to remove multipath effects in the cepstral domain. Finally, an inverse complex cepstrum is calculated yielding a theoretically multipath free direct path estimate in the time domain. Simulations are presented …

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Department Of Defense Hazardous Waste Site Remediation Issues In The Republic Of Korea, Edwin H. Oshiba Dec 1997

Department Of Defense Hazardous Waste Site Remediation Issues In The Republic Of Korea, Edwin H. Oshiba

Theses and Dissertations

The purpose of this research was to provide information to DoD decision makers regarding factors influencing hazardous waste site remediation policy for South Korea. This study addressed: International agreements and U.S. and South Korean laws and policies relevant to hazardous waste sites; objectives of DoD environmental policy makers; extent and effects of soil and groundwater contamination; cleanup precedents set in other foreign countries; availability of resources and technical capabilities to investigate and remediate hazardous waste sites in South Korea; and opportunities for cooperation between the U.S. and South Korean military with regard to hazardous waste site remediation. Data were collected …

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Forecasting Methodologies For Usaf Facility Maintenance And Repair Funding Requirements, Gregory R. Ottoman Dec 1997

Forecasting Methodologies For Usaf Facility Maintenance And Repair Funding Requirements, Gregory R. Ottoman

Theses and Dissertations

Eighteen methodologies for forecasting facility maintenance and repair funding requirements were investigated and analyzed to determine which methodology is best suited for use by the United States Air Force (USAF). The literature review identified four primary factors, or criteria, that determine facility maintenance and repair funding requirements. The methodologies were scored against the four criteria with respect to their appropriate application to USAF requirements. An analysis of dominance was accomplished; the results suggested that no one methodology was clearly superior. Fourteen of the methodologies were dominated, and consequently eliminated from further analysis. Four methodologies were non-dominated: the U.S. Army Construction …

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Scattering From Dielectric Bodies, Jeffery M. Parks Dec 1997

Scattering From Dielectric Bodies, Jeffery M. Parks

Theses and Dissertations

The purpose of this study was to develop an RCS measured database of non-PEC targets and provide an example of its use to validate a code, 3D-RCIE. RCS prediction codes that handle penetrable materials require measured data to determine their accuracy. The materials used for this research include polyethylene and polyurethane with dielectric constants around 2.3 and 1.03, respectively. The polyethylene targets include a mini-arrow, ogive, conesphere, conesphere with a gap, sphere, and a large and small cube. The cubes were the only targets made from the polyurethane foam. Additionally, r-card was applied to the cubes and mini-arrow. The material …

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Fpga Processor Implementation For The Forward Kinematics Of The Umdh, Steven M. Parmley Dec 1997

Fpga Processor Implementation For The Forward Kinematics Of The Umdh, Steven M. Parmley

Theses and Dissertations

The focus of this research was on the implementation of a forward kinematic algorithm for the Utah MIT Dexterous Hand (UMDH). Specifically, the algorithm was synthesized from mathematical models onto a Field Programmable Gate Array (FPGA) processor. This approach is different from the classical, general purpose microprocessor design where all robotic controller functions including forward Kinematics are executed serially from a compiled programming language such as C. The compiled code and subsequent real time operating system must be stored on some form of nonvolatile memory, typically magnetic media such as a fixed or hard disk drive, along with other computer …

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An Analytical Method To Calculate Activity From Measurements Affected By Coincidence Summing, Anthony P. Popovich Dec 1997

An Analytical Method To Calculate Activity From Measurements Affected By Coincidence Summing, Anthony P. Popovich

Theses and Dissertations

An analytical method is developed and applied to find the activities of two radioisotopes based on measurements influenced by true coincidence summing. The method incorporates the solid angle subtended by the detector, the macroscopic cross sections of the materials present, the absolute peak and total efficiencies of the detector, and the modes and probabilities of decay of the radioisotope. With this information, the method corrects for both summing-in and summing-out events. Summing events affect peak counts and cause the calculated activity to differ from the true activity. Thin disk sources of Mo-99 and Cs-136 on the face of a closed-end, …

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Speaker Verification In The Presence Of Channel Mismatch Using Gaussian Mixture Models, Robert B. Reid Dec 1997

Speaker Verification In The Presence Of Channel Mismatch Using Gaussian Mixture Models, Robert B. Reid

Theses and Dissertations

A channel compensation method is sought for use in speaker identification (ID) and verification applications under matched and mismatched training and testing conditions. This work expands on previous work on matched conditions by investigating three techniques on matched and mismatched conditions using the TIMIT and NTIMIT speech databases. First, previous results on 168 speakers are reproduced for matched conditions using Gaussian mixture models (GMM) and mel-frequency cepstral coefficients. Next, cepstral mean subtraction with band limiting (CMSBL) is investigated. The third method, developed in this thesis uses a modified Wiener filtering approach to channel compensation. New GMMs are created for each …

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Architecture, Design, And Implementation Of A Rapidly Prototyped Virtual Environment For A Military Spaceplane, Scott A. Rothermel Dec 1997

Architecture, Design, And Implementation Of A Rapidly Prototyped Virtual Environment For A Military Spaceplane, Scott A. Rothermel

Theses and Dissertations

The new Global Engagement vision places increased emphasis on the Air Force's ability to control and exploit space. A military spaceplane combining reliable access to space, high operational tempos, and multi-mission capabilities is in conceptual stages of development. Virtual environment technology provides an opportunity to investigate system requirements and unconventional interface paradigms for this unique vehicle. A virtual environment architecture and design based on support for a rapid prototyping development process, separation of concerns, and user interface development is presented. The rapid prototyping process allowed management of changing requirements via an evolutionary approach to implementation. Separation of the activities performed …

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A Wire Antenna Designed For Space Wave Radiation Over The Earth Using A Genetic Algorithm, Brian S. Sandlin Dec 1997

A Wire Antenna Designed For Space Wave Radiation Over The Earth Using A Genetic Algorithm, Brian S. Sandlin

Theses and Dissertations

A wire antenna is designed for optimal performance at low elevation angles in the presence of a lossy half-space. A simple genetic algorithm (GA) and GENOCOP III software are each integrated with Numerical Electromagnetics Code Version 4.1 (NEC4.1) to optimize a wire antenna geometry for multiple objectives: power gain, azimuthal symmetry, and input impedance. The performance of the two versions of the integrated GA are compared. Several of the resulting antennas are analyzed, and an antenna is proposed for use in a Remote Intrusion Monitoring System (RIMS). Simulations suggest that the proposed antenna, which is well-matched, offers a significant increase …

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Effects Of Liquid Transpiration Cooling On Heat Transfer To The Diverging Region Of A Porous-Walled Nozzle, Daniel J. Schieb Dec 1997

Effects Of Liquid Transpiration Cooling On Heat Transfer To The Diverging Region Of A Porous-Walled Nozzle, Daniel J. Schieb

Theses and Dissertations

This research effort investigated the effects of evaporation of water on the heat transferred to the wall of the diverging portion of a porous walled nozzle The AFIT High Pressure Shock Tube was used with a two-dimensional Mach 3 nozzle. One flat surface of the nozzle was fitted with a layer of porous stainless steel from the nozzle throat to the exit. This porous material was saturated with water to simulate liquid transpiration cooling. Surface temperature data was taken in this region using fast response coaxial thermocouple. Heat transfer was determined from the surface temperature history. Data was taken for …

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Optimal Non-Coplanar Launch To Quick Rendezvous, Gregory B. Sears Dec 1997

Optimal Non-Coplanar Launch To Quick Rendezvous, Gregory B. Sears

Theses and Dissertations

The purpose of this study was to determine the feasibility of launching a Delta Clipper-like vehicle on an optimal, non-coplanar trajectory to rendezvous with an earth orbiting object in one orbit or less. The focus of the research was to determine what such a trajectory would look like, and to determine the cost, in payload mass, of flying such a trajectory. A model for the ascent trajectory was developed using the dynamics equations of motion, an atmosphere model, and an aerodynamic model for the DC-Y concept vehicle. A boundary value problem was posed and solved for a coplanar rendezvous. The …

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