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User-Interface Coding For The Cern/Geant Nuclear Physics Program, David L. Roetzel, Wilfred J. Braithwaite Jan 1993

User-Interface Coding For The Cern/Geant Nuclear Physics Program, David L. Roetzel, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

Explanations will be given of the various user-written routines required by the Monte Carlo detector-modeling program GEANT, developed by CERN, the European Organization for Nuclear Research. User-written routines must be linked with the CERN library to accomplish the researcher's intentions. Examples will illustrate how GEANT passes information to subprograms needed to model events. Various data structures used by GEANT library calls and included in each user routine, are similarly illustrated. Both computational-speed and memory-size limitations need to be factored into the construction of a simulation model. This will constrain the calls used in the user-written routines. Examples are provided of …


Bulletin 4274 - Tree Planting On The High Rainfall Coastal Plain, Don Bennett, Richard George Jan 1993

Bulletin 4274 - Tree Planting On The High Rainfall Coastal Plain, Don Bennett, Richard George

Bulletins 4000 -

Careful planning can mean the difference between the success or failure of a tree planting program . Healthy , well-e stablished trees stand a better chance of survival, grow faster and are more resistant to insect attack. The need for time-consuming watering in summer is also eliminated.

The high rainfall coastal plain extends from Perth to Busselton and inland to the Darling Scarp. It receives about 800 to 1000 mm annual rainfall.

Site preparation is ideally started in summer. For a winter planting, decide before March where to plant, which varieties and how many trees to plant. Early planning allows …


Glacial Deposits, Vol. 21, 1992-1993, Department Of Geography-Geology Jan 1993

Glacial Deposits, Vol. 21, 1992-1993, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Weapon System Integration For The Afit Virtual Cockpit, William E. Gerhard Jr. Jan 1993

Weapon System Integration For The Afit Virtual Cockpit, William E. Gerhard Jr.

Theses and Dissertations

The Air Force Institute of Technology is continuing research in the Virtual Cockpit. The Virtual Cockpit makes use of high performance graphics workstations, Virtual Environment technology, and Distributed Interactive Simulation network protocols to create a flight simulator based on the capabilities of the McDonnell Douglas F-15E Strike Eagle. The work presented in this thesis focuses on the design and implementation issues for integrating a weapons delivery capability. Weapons simulated include: RADAR and IR guided air- to-air missiles, gravity and precision guided bombs, and a 20mm cannon. Virtual Environment displays used include: color NTSC and monochrome high resolution helmet mounted displays …


Collaborative Multimedia Scientific Design In Shastra, Vinod Anupam, Chandrajit L. Bajaj Jan 1993

Collaborative Multimedia Scientific Design In Shastra, Vinod Anupam, Chandrajit L. Bajaj

Department of Computer Science Technical Reports

No abstract provided.


The Extent Of Multimedia Computer Applications In The Business World, Mei Yee Lim Jan 1993

The Extent Of Multimedia Computer Applications In The Business World, Mei Yee Lim

Honors Theses

The world, or at least I, was all agog when touch screens arrived. My initial contact with touch screens was at a science exhibition in Menara MPPJ, Petaling Jaya, Malaysia in July 1987. That particular exhibit, which encouraged visitors to participate and to experiment with, was a graphic program. Visitors could use their fingers to select the drawing tool or the color they want (which is something like the tools on a MacDraw screen on a Macintosh) and use their fingers to move around the screen to draw anything they want. That added to my fascination with the world of …


The Dynamics Of Growth-Factor-Modified Immune-Response To Cancer Growth: One-Dimensional Models, J. A. Adam Jan 1993

The Dynamics Of Growth-Factor-Modified Immune-Response To Cancer Growth: One-Dimensional Models, J. A. Adam

Mathematics & Statistics Faculty Publications

By characterizing the effect of tumor growth factors as deviations from normal logistic-type growth rates, the spatio-temporal dynamics for a one-dimensional model of cancer growth incorporating immune response are studied. The growth rates considered are classified respectively as normal, activated, inhibited and delay activated. The homogeneous steady states are defined by relative extrema of a ''free energy'' function V(x) for each of the above four cases. This function is of particular importance in studying the coexistence of tumoral and cancer-free steady states, and in identifying the nature (progressive or regressive) of travelling wave solutions to the nonlinear partial differential equation …


Heat Storage And Transport Processes In The Tropical Atlantic Ocean, Andras Kapolnai Jan 1993

Heat Storage And Transport Processes In The Tropical Atlantic Ocean, Andras Kapolnai

OES Theses and Dissertations

Heat storage and transport processes of the tropical Atlantic play an important role in the climate of three continents. The exploration of how the warm water mass maintenance in the equatorial basin depends on various external factors is therefore an important task. This study examines the annual cycle of the warm water mass formation and its transport in the equatorial Atlantic through the interaction of the atmospheric and oceanic boundary layers. Key features of the model are the sea level wind field, equatorial upwelling rate and escape transport of the formed warm water out of the equatorial basin.

The model …


A Model Of Cell Damage In Space Flight, Robert Katz, F. A. Cucinotta, J. W. Wilson, J. L. Shinn, Duc M. Ngo Jan 1993

A Model Of Cell Damage In Space Flight, Robert Katz, F. A. Cucinotta, J. W. Wilson, J. L. Shinn, Duc M. Ngo

Robert Katz Publications

Cell damage by high LET radiations has been described by a phenomenological model (track theory) for 20 years and more. Molecules of biological significance (dry enzymes and viruses) act as 1 hit detectors. Recent additions to the class of I-hit detectors are E. Coli B, and the creation of both single and double strand breaks in SV-40 virus in EO buffer, where indirect effects predominate. The response of cells (survival, transformation, chromosome aberration) to these radiations is typically described by a 4-parameter model whose numerical values are determined by fitting the equations of the theory to experimental data at high …


Development Of A Classification System For Computer Viruses In The Ibm Pc Environment Using The Dos Operating System, Hugh R. Browne Jan 1993

Development Of A Classification System For Computer Viruses In The Ibm Pc Environment Using The Dos Operating System, Hugh R. Browne

Theses : Honours

The threat to computers worldwide from computer viruses is increasing as new viruses and variants proliferate. Availability of virus construction tools to facilitate 'customised' virus production and wider use of more sophisticated means of evading detection, such as encryption, polymorphic transformation and memory resident 'stealth' techniques increase this problem. Some viruses employ methods to guard against their own eradication from an infected computer, whilst other viruses adopt measures to prevent disassembly of the virus for examination and analysis. Growth in computer numbers and connectivity provide a growing pool of candidate hosts for infection. Standardised and flexible systems for classification and …


Scattering Parameters For An Epstein Profile In A Half-Space, J. A. Adam Jan 1993

Scattering Parameters For An Epstein Profile In A Half-Space, J. A. Adam

Mathematics & Statistics Faculty Publications

The reflection of waves for a stratified medium in (-∞, ∞) can be studied by transforming the hypergeometric differential equation into a wave equation. In the context of an astrophysical problem [1], the corresponding analysis is carried out for an Epstein profile in (0, ∞). This profile represents a scattering potential in quantum mechanical terminology: its properties are briefly discussed.


Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa Jan 1993

Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa

Reports

Executive Summary: Many pathways exist for transportation agencies and other public and private agencies to become responsible for sites contaminated by hazardous wastes. As a reult, agencies frequently face a multitude of lega, regulatory, financial, technical, and health risk problems. When transportation agencies become involved in the remediation of hazardous waste sites, the common practice is to hire consultants and contractors for the clean up process. Because the field of hazardous waste site remediation is changing so rapidly, agency personnel evaluating the consultant's recommendations need to ahve access to the most recent regulatory and remediation information. Early stages of the …


Interpretation Of Drill Log Data: Dlog3d - A Probabilistic Tool For Analyzing Subsurface Soil Variability, Alaa El-Din Ali, Upmanu Lall Jan 1993

Interpretation Of Drill Log Data: Dlog3d - A Probabilistic Tool For Analyzing Subsurface Soil Variability, Alaa El-Din Ali, Upmanu Lall

Reports

Groundwater contamination potential is directly related to the location of zones of high hydraulic conductivity. Sedimentary depositional environments can be quite complex. Pockets of sand of varying thickness and orientation may be scattered over the aquifer. A contaminant pathway can esist where these pockets or lenses are interconnected. Aquifer pump tests do not provide useful information on the occurrence of such lenses. Drill log data directly sample the soil, but may represent very local sections of the aquifer, and are of relatively poor quality. Here we present a methodology (DLOG3D) that allows a probabilistic interpretation of drill log data that …


Polynuclear Mixed-Valence Complexes, David A. Rockcliffe Jan 1993

Polynuclear Mixed-Valence Complexes, David A. Rockcliffe

Dissertations

No abstract provided.


Effect Of Solvent On 1,3-Dipolar Cycloaddition Transition States, Sheila Louise Celsor Jan 1993

Effect Of Solvent On 1,3-Dipolar Cycloaddition Transition States, Sheila Louise Celsor

Dissertations

No abstract provided.


Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth Jan 1993

Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth

All Peer-Reviewed Publications

Trypanosoma (Nannomonas) congolense comprises morphologically identical but genetically heterogeneous parasites infective to livestock and other mammalian hosts; three different genotypes of this parasite have been described previously. Restriction enzyme fragment length polymorphisms (RFLPs) in both kinetoplast DNA minicircle and nuclear DNA sequences, and randomly amplified polymorphic deoxyribonucleic acid (RAPD) patterns have been used here to demonstrate the existence of another type of T. (N.) congolense that is genotypically distinct from those that have so far been characterized at the molecular level. A highly repetitive, tandemly arranged DNA sequence and oligonucleotide primers, for use in polymerase chain reaction (PCR) amplification are …


Symphony: A Hardware, Operating System, And Protocol Processing Architecture For Distributed Multimedia Applications, Andreas D. Bovopoulos, R. Gopalakrishnan, Saied Hosseini Jan 1993

Symphony: A Hardware, Operating System, And Protocol Processing Architecture For Distributed Multimedia Applications, Andreas D. Bovopoulos, R. Gopalakrishnan, Saied Hosseini

All Computer Science and Engineering Research

This paper explores the architectural requirements for computers to be able to process multimedia data streams such as video and audio. The I/O subsystem is shown to be a bottleneck, and a network backplane approach is suggested to alleviate this. The need to provide end-to-end performance guarantees requires predictable performance of intra-machine communication, and a schedulable bus with reservation is proposed to achieve this. In addition this requires operating system (OS) mechanisms to negotiate and enforce QoS requirements of applications. A real-time microkernel executive is proposed for each autonomous unit. Requirements for real-time microkernel exeutive is proposed for each autonomous …


Provo Pollution Prevention Program, Donald H. Stedman, Gary A. Bishop, James E. Peterson, Theresa Hosick Jan 1993

Provo Pollution Prevention Program, Donald H. Stedman, Gary A. Bishop, James E. Peterson, Theresa Hosick

Fuel Efficiency Automobile Test Publications

No abstract provided.


Hysteresis And Anchoring Energy In Ferroelectric Liquid Crystals, Yuri Panarin Jan 1993

Hysteresis And Anchoring Energy In Ferroelectric Liquid Crystals, Yuri Panarin

Articles

The frequency dispersion of the coercive force of Ferroelectric Liquid Crystals (FLC) cells has been detected and examined in the range of infralow (lower than 0.1 Hz) frequencies. To clarify the low-frequency dispersion, the model has been suggested, based on the arrangement of free charges and well describing the experimental curves. The method for determination of the energy of FLC anchoring at the surface, developed on the basis of the static hysteresis loop, has been proposed. The dependence of bistability and the anchoring energy upon the orientant layer thickness has experimentally been investigated.


Aminolysis Of Activated Esters Of Indole-3-Acetic Acid In Acetonitrile, Michael J. Pfeiffer, Samir B. Hanna Jan 1993

Aminolysis Of Activated Esters Of Indole-3-Acetic Acid In Acetonitrile, Michael J. Pfeiffer, Samir B. Hanna

Chemistry Faculty Research & Creative Works

Seven activated esters of indole-3-acetic acid (IAA) [4-oxo-l,2,3-benzotriazin-3-yl indole-3-acetate (IAA-3HBO), succinimido indole-3-acetate (IAA-NHS), 5-norbornene-1,3-dicarboximido indole-3-acetate (IAA-NHND), phthalimido indole-3-acetate (IAA-NHP), naphthalimido indole-3-acetate (IAA-NHN), 4-nitrophenyl indole-3-acetate (IAA-4NP), 8-quinolyl indole-3-acetate (IAA-8HQ)] were prepared and characterized. Their kinetics of aminolysis with butylamine, piperidine, and pyrrolidine in acetonitrile were investigated. In general, the observed pseudo-first-order rate constants, kobs, fit the two-term rate equation kobs = k1[amine] + k2[amine]2. For the aminolysis of six of the esters with piperidine there was no measurable k2 term. The 8-hydroxyquinoline ester and N-hydroxy-naphthalimide ester of indole-3-acetic acid had no measurable k2 term for aminolysis with either pyrrolidine or piperidine. …


Tetrabutylammonium Benzoate‐Initiated Polymerization Of Propylene Oxide, Xuemin Chen, Michael R. Van De Mark Jan 1993

Tetrabutylammonium Benzoate‐Initiated Polymerization Of Propylene Oxide, Xuemin Chen, Michael R. Van De Mark

Chemistry Faculty Research & Creative Works

The polymerization of propylene oxide by the benzoate anion was aided through the use of the tetrabutylammonium counterion. The effect of the tetrabutylammonium ion was to increase the solubility of the salt and to increase the ion separation. The polymerization was carried out in a pressure reactor at temperatures from 40 to 108°C, producing polymer yields of 2–78%. The study addressed the general effects of solvent, temperature, and ratio of initiator to monomer. © 1993 John Wiley & Sons, Inc. Copyright © 1993 John Wiley & Sons, Inc.


Discussion Paper: Public Lands Communities, Sarah F. Bates, University Of Colorado Boulder. Natural Resources Law Center, University Of Colorado Boulder. Western Lands Program Jan 1993

Discussion Paper: Public Lands Communities, Sarah F. Bates, University Of Colorado Boulder. Natural Resources Law Center, University Of Colorado Boulder. Western Lands Program

Books, Reports, and Studies

30 p. ; 28 cm


Cathodoluminescence Spectroscopy Of Zinc Germanium Phosphide Zngep2, Michael R. Gregg Dec 1992

Cathodoluminescence Spectroscopy Of Zinc Germanium Phosphide Zngep2, Michael R. Gregg

Theses and Dissertations

Zinc Germanium Phosphide (ZnGeP2) is a nonlinear semiconductor suitable for use as a laser tuning element over the two to six micron wavelength range. Although this crystal has been studied in the past, its luminescent properties are not yet well understood. In this present study, ZnGeP2 has been examined using cathodoluminescence spectroscopy (CL). Specifically, the spectral dependence of the CL was obtained as a function of electron beam energy, beam current and temperature. The resulting CL was found to be polarized with a peak structure that was dependent on the polarization. This peak structure observed by CL …


Design And Characterization Of Optically Pumped Vertical Cavity Surface Emitting Lasers, Richard J. Bagnell Dec 1992

Design And Characterization Of Optically Pumped Vertical Cavity Surface Emitting Lasers, Richard J. Bagnell

Theses and Dissertations

Vertical Cavity Surface Emitting Lasers (VCSELs) are a form of semiconductor laser which have their cavity oriented orthogonally to the plane of the wafer. The orientation necessitates short cavities, highly reflective mirrors and a relatively high gain/loss ratio. Even so, the resultant superior exit beam characteristics and the tight packing density of the finished lasers provide strong motivation for pursuing the growth of these structures. This thesis details the design of an optically pumped InGaAs multiple quantum well periodic gain structure VCSEL with a 950 nm lasing wavelength. These growths were to be a first attempt at VCSEL construction, so …


Face Recognition With Neural Networks, Dennis L. Krepp Dec 1992

Face Recognition With Neural Networks, Dennis L. Krepp

Theses and Dissertations

This study investigated neural networks for face verification and classification. The research concentrated on developing a neural network based feature extractor and/or classifier to perform authorized user verification in a realistic work environment. Recognition accuracy, system assumptions, training time, and execution time were analyzed to determine the feasibility of a neural network approach. Data was collected using a camcorder and two segmentation schemes: manual segmentation and motion-based, automatic segmentation. Data consisted of over 2000. 32x32 pixel, 8 bit gray scale images of 52 subjects; each subject had two to ten days worth of images collected. Several training and test sets …


Automated Logistics Information Systems: A Case Study, James E. Hogue Dec 1992

Automated Logistics Information Systems: A Case Study, James E. Hogue

Theses and Dissertations

A change within the Air Force has shifted management responsibilities within the logistics community. Formerly diverse functions have come under the purview of a single manager-the Logistics Group Commander-who has inherited information systems that may riot be able to provide consolidated information for informed and accurate decision making. The purpose of this thesis was to describe the current and potential ability for three logistics information management systems to share data: Standard Base Supply System, Consolidated Aircraft Management System, and On-Line Vehicle Information Management System. A systems model was synthesized from the literature review to determine what components of a system …


Integrated Diagnostic Expert System Model (Idesm): A Model For The Conversion Of Fault Isolation Procedures Into An Integrated Diagnostic Expert System, Robert J. Lacey, Glen D. Steemson Dec 1992

Integrated Diagnostic Expert System Model (Idesm): A Model For The Conversion Of Fault Isolation Procedures Into An Integrated Diagnostic Expert System, Robert J. Lacey, Glen D. Steemson

Theses and Dissertations

The purpose of this research was to develop a model to convert existing hardcopy maintenance manual fault isolation procedures into electronic format and to partially automate the fault isolation process. A comprehensive model was developed which comprised four major components: user interface, expert system submodel, hypermedia submodel, and a submodel integration shell. Using this model, the F 15E nose landing gear fault isolation procedures were transformed into a rule based expert system. An existing hypermedia information base was expanded and subsequently integrated with the expert system to form the prototype application. The prototype was evaluated by engineering and maintenance personnel …


Ada Implementation Of An Object Data Repository, Stephen P. Perucca Dec 1992

Ada Implementation Of An Object Data Repository, Stephen P. Perucca

Theses and Dissertations

The many benefits of object-oriented software development such as encapsulation and extendibility have inspired numerous models of the object- oriented paradigm. Rumbaugh's Object Modeling Technique (OMT) is an object- oriented model that uses three submodels. The object, dynamic, and functional submodels of the OMT describe the data, behavioral, and processing aspects of a system by using entity-relationship, state-transition, and data flow models. Cross-links relate how the three submodels tie together. Two metamodels (models of models) of the OMT are developed using the OMT methodology and notation. The essential data elements of the OMT are abstracted into a data metamodel, and …


Dielectric Properties And Ferroelectricity In Main-Chain Nematic Polymers, Eugene Terentjev, Rolfe G. Petschek Nov 1992

Dielectric Properties And Ferroelectricity In Main-Chain Nematic Polymers, Eugene Terentjev, Rolfe G. Petschek

Faculty Scholarship

The longitudinal dielectric susceptibility of a polar (directed) thermotropic main-chain nematic polymer is derived in the mean-field approximation, accounting for long-range interaction forces and the local-field effects in the media. It is shown that this susceptibility exponentially increases for some range of orientational order and then either diverges or saturates at some characteristic degree of order. This is expected in some circumstances to result in a true ferroelectric phase. A simple calculation of this transition is given, assuming that long-range dipolar interactions are the only relevant polar interactions. Other relevant effects and the limitations of our approximation are discussed briefly.


The Probe, Issue 127 - November 1992 Nov 1992

The Probe, Issue 127 - November 1992

The Probe: Newsletter of the National Animal Damage Control Association

Contents:

Principles of Wildlife Damage Management
CALENDAR OF UPCOMING EVENTS
ADC Personnel Changes
Publications Available
ADC Takes Leading Role in Educational Efforts
Cattle Losses to Predators in 1991
"ADC" — New Animal Damage Control Magazine
Maine Gull Project Shows Positive Results
Wolf Sightings in Yellowstone?