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1999

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Articles 181 - 210 of 2333

Full-Text Articles in Physical Sciences and Mathematics

Teaching Object Technology In Industry Short Courses, David S. Janzen Nov 1999

Teaching Object Technology In Industry Short Courses, David S. Janzen

Computer Science and Software Engineering

No abstract provided.


1991-1992 & 1996 Utah Usage Of Ems Services By Children: Year Iii Research Report, Intermountain Injury Control Research Center, U.S. Department Of Commerce Nov 1999

1991-1992 & 1996 Utah Usage Of Ems Services By Children: Year Iii Research Report, Intermountain Injury Control Research Center, U.S. Department Of Commerce

All U.S. Government Documents (Utah Regional Depository)

This study examined how Utah children used emergency medical services (EMS) and related hospital care in 1991-1992. The EMS and hospital records were linked using special software (probabilistic linkage) . The principal findings of the study concerned the care of young children less than 5 years of age. They received fewer procedures prior to being transported to a hospital and required more time at the scene for assessment. Some interventions such as splinting of fractured arms prior to transport to a hospital were related to reduced hospital charges. Ambulance and hospital charges for children were estimated to by $35,000,000 not …


The Coral Reef Fishes Of Broward County Florida, Species And Abundance: A Work In Progress, B. D. Ettinger, David S. Gilliam, L. K. B. Jordan, Robin L. Sherman, Richard E. Spieler Nov 1999

The Coral Reef Fishes Of Broward County Florida, Species And Abundance: A Work In Progress, B. D. Ettinger, David S. Gilliam, L. K. B. Jordan, Robin L. Sherman, Richard E. Spieler

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

The inshore environment of Broward County, FL consists of three coral reef/hard bottom reef tracts, separated by sand substrate, running parallel to the coast in sequentially deeper water. At quarter nautical mile intervals, for a five mile coastline section, fishes were censused at western, eastern and crest sites of each of the three reef tracts. On SCUBA and using the Bohnsack/Bannerot point-count method, we recorded: fish abundance, species richness, size, and general habitat of an imaginary cylinder 15 m in diameter. The position of each site was recorded by DGPS after census. One hundred and eighty-one sites were censused during …


Vegetation Trend In The East Kimberley Region : An Analysis Of Ground Monitoring Data From 1991-1998, Noelene Duckett, Paul Novelly, Ian Watson Nov 1999

Vegetation Trend In The East Kimberley Region : An Analysis Of Ground Monitoring Data From 1991-1998, Noelene Duckett, Paul Novelly, Ian Watson

Research Reports

This document summarises the analyses carried out on the ground monitoring data from the Kimberley region of Western Australia as part of the Natural Heritage Trust project 953024 - ‘'Development of Information Products for Reporting Rangeland Changes.”


Recounting Fibonacci And Lucas Identities, Arthur T. Benjamin, Jennifer J. Quinn Nov 1999

Recounting Fibonacci And Lucas Identities, Arthur T. Benjamin, Jennifer J. Quinn

All HMC Faculty Publications and Research

No abstract provided in this article.


Interior Weyl-Type Solutions To The Einstein-Maxwell Field Equations, Brendan Guilfoyle Nov 1999

Interior Weyl-Type Solutions To The Einstein-Maxwell Field Equations, Brendan Guilfoyle

Preprints

Static solutions of the electro-gravitational field equations exhibiting a functional relationship between the electric and gravitational potentials are studied. General results for these metrics are presented which extend previous work of Majumdar. In particular, it is shown that for any solution of the field equations exhibiting such a Weyl-type relationship, there exists a relationship between the matter density, the electric field density and the charge density. It is also found that the Majumdar condition can hold for a bounded perfect fluid only if the matter pressure vanishes (that is, charged dust). By restricting to spherically symmetric distributions of charged matter, …


Center For Sustainable Agricultural Systems Newsletter, November/December 1999 Nov 1999

Center For Sustainable Agricultural Systems Newsletter, November/December 1999

Center for Sustainable Agricultural Systems: Newsletter (1993–2000)

Contents:

Conference Shows Large Interest in Small Farms

University Role in Biotechnology: What Do People Say and Why?

Loss of Biodiversity a Growing Concern


A Near-Surface Microstructure Sensor System Used During Toga Coare. Part Ii: Turbulence Measurements, Alexander Soloviev, Roger Lukas, Peter Hacker, H. Schoeberlein, M. Baker, A. Arjannikov Nov 1999

A Near-Surface Microstructure Sensor System Used During Toga Coare. Part Ii: Turbulence Measurements, Alexander Soloviev, Roger Lukas, Peter Hacker, H. Schoeberlein, M. Baker, A. Arjannikov

Marine & Environmental Sciences Faculty Articles

New techniques developed for near-surface turbulence measurements during the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean–Atmosphere Response Experiment (COARE) employ a difference in spatial scales of turbulence and surface waves. According to this approach, high relative speed of the measurements provides separation of the turbulence and surface wave signals. During the TOGA COARE field studies, highresolution probes of pressure, temperature, conductivity, fluctuation velocity, and acceleration were mounted on the bow of the vessel at a 1.7-m depth in an undisturbed region ahead of the moving vessel. The localization in narrow frequency bands of the vibrations of the bow sensors allows …


Cationic 5,10,15,20-Tetrakis(N-Methylpyridinium-4-Yl)Porphyrin Fully Intercalates At 5‘-Cg-3‘ Steps Of Duplex Dna In Solution, Anton B. Guliaev, Neocles B. Leontis Nov 1999

Cationic 5,10,15,20-Tetrakis(N-Methylpyridinium-4-Yl)Porphyrin Fully Intercalates At 5‘-Cg-3‘ Steps Of Duplex Dna In Solution, Anton B. Guliaev, Neocles B. Leontis

Chemistry Faculty Publications

The interaction of 5,10,15,20-tetrakis(N-methylpyridinium-4-yl)p (T4MPyP4+ with the oligonucleotide DNA duplex [d(GCACGTGC)](2) was studied by two-dimensional 1H NMR spectroscopy, optical absorbance, circular dichroism, and molecular dynamics simulation employing particle mesh Ewald methods. T4MPyP4+ is one of the largest aromatic molecules for which intercalative binding to DNA has been proposed, although this has been called into question by recent X-ray crystallographic work [Lipscomb et al. (1996) Biochemistry 35, 2818-2823]. T4MPyP4+ binding to [d(GCACGTGC)]2 produced a single set of (mostly) upfield-shifted DNA resonances in slow exchange with the resonances of the free DNA. Intra- and intermolecular NOEs …


Bulletin 4396 - Byenup Hill Focus Catchment Benefit: Cost Analysis, Allan Herbert Nov 1999

Bulletin 4396 - Byenup Hill Focus Catchment Benefit: Cost Analysis, Allan Herbert

Bulletins 4000 -

The main text of this document concentrates on the costs of the proposed strategies, and the on-farm financial benefits from forecast production changes - in particular the production differences between the 'do nothing' and 'with strategy' scenarios.

Members of the catchment group indicated however that their main focus was on preserving their capital base. Hence some discussion of the values of land lost to salt and premiums/discounts for 'landcared' vs 'unlandcared' land appears later in the report. Economics literature suggests that including changes in land values into these analyses is incorrect. It is argued that production differences are actually captured …


Investigation Of Image Feature Extraction By A Genetic Algorithm, Steven P. Brumby, James P. Theiler, Simon J. Perkins, Neal R. Harvey, John J. Szymanski, Jeffrey J. Bloch, Melanie Mitchell Nov 1999

Investigation Of Image Feature Extraction By A Genetic Algorithm, Steven P. Brumby, James P. Theiler, Simon J. Perkins, Neal R. Harvey, John J. Szymanski, Jeffrey J. Bloch, Melanie Mitchell

Computer Science Faculty Publications and Presentations

We describe the implementation and performance of a genetic algorithm which generates image feature extraction algorithms for remote sensing applications. We describe our basis set of primitive image operators and present our chromosomal representation of a complete algorithm. Our initial application has been geospatial feature extraction using publicly available multi-spectral aerial-photography data sets. We present the preliminary results of our analysis of the efficiency of the classic genetic operations of crossover and mutation for our application, and discuss our choice of evolutionary control parameters. We exhibit some of our evolved algorithms, and discuss possible avenues for future progress.


Confined Water In Hydrophobic Nanopores: Dynamics Of Freezing Into Bilayer Ice, Jan Slovak, Kenichiro Koga, Hideki Tanaka, Xiao Cheng Zeng Nov 1999

Confined Water In Hydrophobic Nanopores: Dynamics Of Freezing Into Bilayer Ice, Jan Slovak, Kenichiro Koga, Hideki Tanaka, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Molecular dynamics simulations for a thin film of water confined to a slit nanopore are performed in order to investigate the dynamic process of crystallization of the system. The system upon freezing creates a bilayer ice crystal composed of two layers of hexagonal rings. We perform one simulation at T=257 K during which the system remains a supercooled liquid state, and another one at T=253 K during which the system freezes. Many patterns of molecular arrangement are found upon freezing, and an account is given of the origin of multiple peaks in the distributions of binding energy and …


Imaging Point Defects In A Liquid Environment: A Model Afm Study, Kenichiro Koga, Xiao Cheng Zeng Nov 1999

Imaging Point Defects In A Liquid Environment: A Model Afm Study, Kenichiro Koga, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Effects of the liquid on atomic force microscopy (AFM) imaging are examined for a model system consisting of a hexagonal flake of seven Lennard-Jones (LJ) atoms as a multiatom tip, a monolayer of LJ crystal containing a single point defect as a substrate, and three-site model water as the liquid. A previous simulation [Koutsos et al., Europhys. Lett. 26, 103 (1994)] has shown that the true atomic resolution of a point defect cannot be achieved in vacuum by use of the multiatom tip. Here we examine the feasibility of such atomic resolution when both the tip and substrate are immersed …


Geosciences Newsletter- 1999, Department Of Geosciences Nov 1999

Geosciences Newsletter- 1999, Department Of Geosciences

Geological and Environmental Sciences News

Vol.1, No. 24

  • Dear Alumni and Friends
  • Faculty News
  • Graduate Student News
  • Student News
  • Alumni News
  • Donations


The Probe, Issue 206 – November 1999 Nov 1999

The Probe, Issue 206 – November 1999

The Probe: Newsletter of the National Animal Damage Control Association

Wildlife Damage Conferences: When, Where, and Why? -- Robert M. Timm, Editor, THE PROBE
Booklet Review:"The Problem with Skunks!!" by Edward Kellems (34 pages, illustrated. $14.95)
New NWCO Web Page url is http://www.wildlifedamagecontrol.com/nwcoa.htm

Abstracts from the 2nd International Wildlife Management Congress, Hungary
Human Disturbance as a Design Factor to Aid Displacement of Canada Geese from Urban Parks -- P. C. Whitford, Biology Department, Capital University, Columbus, OH
Leopard Problems in Nepal -- T. M. Maskey, National Parks and Wildlife Conservation Department, Kathmandu, Nepal
Elk-human Conflict Management in Banff National Park, Alberta, Canada -- J. A. McKenzie, Banff National Park Wildlife …


Light Backscatter Of Milk Products For Transition Sensing Using Optical Fibers, Frederick A. Payne, Czarena L. Crofcheck, Sue E. Nokes, Klat C. Kang Nov 1999

Light Backscatter Of Milk Products For Transition Sensing Using Optical Fibers, Frederick A. Payne, Czarena L. Crofcheck, Sue E. Nokes, Klat C. Kang

Biosystems and Agricultural Engineering Faculty Publications

Transition sensors are needed, particularly in the dairy industry, for detecting transitions in pipe flow systems from product-to-water or product-to-product (such as from chocolate to vanilla ice cream mix). Transition information is used to automatically sequence valves to minimize product waste. Optical fibers were used to measure light backscatter between 400 and 950 nm as a function of milk concentration in water and milkfat concentration in milk. The normalized response (100% for product and 0% for water) as a function of product concentration in water was approximately logarithmic for skim milk between 400 and 900 nm and approximately linear for …


Student Fact Book, Fall 1999, Twenty Third Annual Edition November 1999, Wright State University, Office Of Student Information Systems, Wright State University Nov 1999

Student Fact Book, Fall 1999, Twenty Third Annual Edition November 1999, Wright State University, Office Of Student Information Systems, Wright State University

Wright State University Student Fact Books

The student fact book has general demographic information on all students enrolled at Wright State University for Fall Quarter, 1999.


Velocity Distributions Of C Atoms In Co+ Dissociative Recombination: Implications For Photochemical Escape Of C From Mars, Jane L. Fox, Aleksander Hać Nov 1999

Velocity Distributions Of C Atoms In Co+ Dissociative Recombination: Implications For Photochemical Escape Of C From Mars, Jane L. Fox, Aleksander Hać

Physics Faculty Publications

We have carried out Monte Carlo calculations to determine the velocity distributions of C atoms produced by dissociative recombination of CO+ using recent data for the branching ratios of various allowed channels and ion and electron temperatures appropriate to the Martian thermosphere. We find that the fractions of 12C atoms with velocities greater than the escape velocity are ∼ 0.66 and ∼ 0.62, and those for 13C are ∼ 0.47 and ∼ 0.48 at the plasma temperatures characteristic of the exobases at low and high solar activities, respectively. The ratio of the escape fractions of 13C …


Strain Splitting Of The Gamma(5) And Gamma(6) Free Excitons In Zno, D. C. Reynolds, David C. Look, B. Jogai, C. W. Litton, T. C. Collins, M T. Harris, M. J. Callahan, J. S. Bailey Nov 1999

Strain Splitting Of The Gamma(5) And Gamma(6) Free Excitons In Zno, D. C. Reynolds, David C. Look, B. Jogai, C. W. Litton, T. C. Collins, M T. Harris, M. J. Callahan, J. S. Bailey

Physics Faculty Publications

High-quality ZnO crystals have been grown by vapor-phase techniques and by the hydrothermal method. Depending on the surface preparation technique, some hydrothermally grown crystals contain strain. These strains result in energy shifts of the free excitons as well as relaxation of the selection rules. The Γ6 unallowed exciton is observed in these samples without the application of a magnetic field. The Γ6 exciton is also observed to split in a strain field, consistent with the Γ9 symmetry for the top valence band in ZnO. The Γ5 and Γ6 excitons have been observed to split in …


A New Numerical Model Of Coupled Inland Ice Sheet, Ice Stream, And Ice Shelf Flow And Its Application To The West Antarctic Ice Sheet, Christina L. Hulbe, D. R. Macayeal Nov 1999

A New Numerical Model Of Coupled Inland Ice Sheet, Ice Stream, And Ice Shelf Flow And Its Application To The West Antarctic Ice Sheet, Christina L. Hulbe, D. R. Macayeal

Geology Faculty Publications and Presentations

We have developed a dynamic/thermodynamic finite element numerical model that couples inland ice sheet, ice stream, and ice shelf dynamics. This new model stands apart from other whole ice sheet models in its explicit treatment of ice stream flow. Additionally, the model accounts for both horizontal and vertical advection and diffusion of temperature in the flowing ice. In present day simulations of the West Antarctic Ice Sheet (WAIS), modeled ice velocity agrees well with observed ice flow. In particular, the model reproduces the pattern of speed variation across ice streams although the continuous downstream speed up of ice flow cannot …


An Access-Control Calculus For Spanning Administrative Domains, Jon Howell, David Kotz Nov 1999

An Access-Control Calculus For Spanning Administrative Domains, Jon Howell, David Kotz

Computer Science Technical Reports

In our quest to give users uniform access to resources unimpeded by administrative boundaries, we discovered that we needed transitive sharing among users, with the possibility of restricted access along each sharing link. To achieve that goal, we extend Lampson et al.'s calculus for access control to support restricted delegations. We discuss the advantages of our extension, including the simplification of constructs like ACLs and statement expiration. We also apply our extension to model the Simple Public Key Infrastructure and make suggestions about its future development. Our extended calculus exposes some surprising consequences in such systems that use restricted delegation.


Laser-Induced Stabilization Of Autoionizing States, Heider N. Ereifej, J. Greg Story Nov 1999

Laser-Induced Stabilization Of Autoionizing States, Heider N. Ereifej, J. Greg Story

Physics Faculty Research & Creative Works

Stabilization of autoionizing states of barium by laser-induced, stimulated emission of light is demonstrated. Relative to purely flourescent stabilization, the data clearly show an enhancement of the stabilization process for laser pulses short compared to the flourescent lifetime of the autoionizing states. Shakeup spectra in which the principal quantum number of both electrons changes during the stimulated emission process are also clearly demonstrated.


Measurement Of B Quark Fragmentation Fractions In The Production Of Strange And Light B Mesons In Pp̅ Collisions At √S =1.8 Tev, F. Abe, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Nov 1999

Measurement Of B Quark Fragmentation Fractions In The Production Of Strange And Light B Mesons In Pp̅ Collisions At √S =1.8 Tev, F. Abe, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

A new technique to measure the ratio of b quark fragmentation fractions in pp̅ collisions is described. Using a 70-pb-1 sample of low-mass dimuon trigger data recorded with the Collider Detector at Fermilab, we identify B mesons by observing the double semileptonic decays bcμX with csμ X. By counting the numbers of K*(892) 0, K*(892) 1, and Φ (1020) mesons produced in association with these muon pairs, we measure the ratio of strange to nonstrange B meson production to be fs /( fu+ i>fd)=[21.0±3.6(stat) -3.0 …


Low-Frequency Noise In N-Gan With High Electron Mobility, M. E. Levinshtein, S. L. Rumyantsev, David C. Look, Richard J. Molnar, M. A. Khan, G. Simin, V. Adivarahan, M. S. Shur Nov 1999

Low-Frequency Noise In N-Gan With High Electron Mobility, M. E. Levinshtein, S. L. Rumyantsev, David C. Look, Richard J. Molnar, M. A. Khan, G. Simin, V. Adivarahan, M. S. Shur

Physics Faculty Publications

We report on the results of measurements of low frequency noise in n-type gallium nitride (GaN) grown on sapphire with 300 K electron mobility of 790 cm2/V s. The noise spectra have the form of 1/f noise with a Hooge parameter α of approximately 5×10−2. This value of α is two orders of magnitude smaller than that observed before in n-GaN. The obtained results show that the level of flicker noise in GaN, just like that in GaAs and Si, strongly depends on the structural perfection of the material (the amplitude of the …


Stabilization Of Polystyrene By Friedel-Crafts Chemistry: Effect Of Position Of Alcohol And The Catalyst, Jin Zhu, Michael A. Mckinney, Charles Wilkie Nov 1999

Stabilization Of Polystyrene By Friedel-Crafts Chemistry: Effect Of Position Of Alcohol And The Catalyst, Jin Zhu, Michael A. Mckinney, Charles Wilkie

Chemistry Faculty Research and Publications

Polystyrene has been copolymerized with 4-vinylbenzyl alcohol, 4-(2-hydroxyethyl)styrene, and 4-(3-hydroxypropyl)styrene and it has been shown that thermal cross-linking of these copolymers is dependent upon the alcohol content. When the alcohol content is low, no thermal cross-linking is observed. When various phosphate esters are present as catalysts with these low alcohol content copolymers, cross-linking is observed at temperatures of about 250°C but not at lower temperatures. Cross-linking enhances the thermal stability of the copolymers. Studies of the thermal stability of the copolymers and their blends with the catalysts have been performed using thermogravimetric analysis and thermogravimetric analysis coupled to Fourier transform …


To Host A Legacy System To The Web, Miguel Angel Bustamante Nov 1999

To Host A Legacy System To The Web, Miguel Angel Bustamante

Student Work

The dramatic improvements in global interconectivity due to intranets, extranets and the Internet has led to many enterprises to consider migrating legacy systems to a web based systems. While data remapping is relatively straightforward in most cases, greater challenges lie in adapting legacy application software. This research effort describes an experiment in which a legacy system is migrated to a web-client/server environment. First, this thesis reports on the difficulties and issues arising when porting a legacy system International Invoice (IIMM) to a web-client/server environment. Next, this research analyzes the underlying issues, and offer cautionary guidance to future migrators and finally …


Peak-To-Mean Power Control In Ofdm, Golay Complementary Sequences, And Reed–Muller Codes, James A. Davis, Jonathan Jedwab Nov 1999

Peak-To-Mean Power Control In Ofdm, Golay Complementary Sequences, And Reed–Muller Codes, James A. Davis, Jonathan Jedwab

Department of Math & Statistics Faculty Publications

We present a range of coding schemes for OFDM transmission using binary, quaternary, octary, and higher order modulation that give high code rates for moderate numbers of carriers. These schemes have tightly bounded peak-to-mean envelope power ratio (PMEPR) and simultaneously have good error correction capability. The key theoretical result is a previously unrecognized connection between Golay complementary sequences and second-order Reed–Muller codes over alphabets ℤ2h. We obtain additional flexibility in trading off code rate, PMEPR, and error correction capability by partitioning the second-order Reed–Muller code into cosets such that codewords with large values of PMEPR are isolated. …


Crossover Photonic Switching Network With Cmos/Seed Smart Pixel Device And 2d Optical Fiber Bundle Array, Fengguang Luo, Mingcui Cao, Qiaoyan Hu, Anjun Wan, Jun Xu, Cong Deng, Deming Liu Nov 1999

Crossover Photonic Switching Network With Cmos/Seed Smart Pixel Device And 2d Optical Fiber Bundle Array, Fengguang Luo, Mingcui Cao, Qiaoyan Hu, Anjun Wan, Jun Xu, Cong Deng, Deming Liu

Electro-Optics and Photonics Faculty Publications

A 16 X 16 Crossover photonic switching network with hybrid integrated CMOS/SEED smart pixel device and 2D optical fiber bundle array I/O access device is reported in this paper. SEEd array devices ar used as light receivers and transmitters, while CMOS devices make efficient logical processing. 4 X 40 2D multilayer optical fiber bundle arrays are fabricated and are used as I/O access devices in the crossover photonic switching network. The center to center spacing between adjacent optical fibers in the same layer of the fiber array is 125micrometers , and the spacing between adjacent layers is 250micrometers . Displacing …


Intersecting Chains In Finite Vector Spaces, Eva Czabarka Nov 1999

Intersecting Chains In Finite Vector Spaces, Eva Czabarka

Faculty Publications

We prove an Erdős–Ko–Rado-type theorem for intersecting k-chains of subspaces of a finite vector space. This is the q-generalization of earlier results of Erdős, Seress and Székely for intersecting k-chains of subsets of an underlying set. The proof hinges on the author's proper generalization of the shift technique from extremal set theory to finite vector spaces, which uses a linear map to define the generalized shift operation. The theorem is the following.

For c = 0, 1, consider k-chains of subspaces of an n-dimensional vector space over GF(q), such that the smallest subspace in any chain has dimension at least …


Runoff From Fescue Plots Treated With Trimec, Cristopher G. Moss, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams Nov 1999

Runoff From Fescue Plots Treated With Trimec, Cristopher G. Moss, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams

Biosystems and Agricultural Engineering Faculty Publications

Runoff of herbicides can promote adverse impacts in receiving waters. The objective of this study was to assess the effects of rainfall delay, herbicide application rate, rainfall intensity, and pre-application rainfall on runoff of TRIMEC (a combination of 2,4-D, dicamba, and mecoprop), a herbicide that is commonly used in central Kentucky. The levels of rainfall delay were 0, 2, and 4 d following application; and the levels of herbicide application rate were 0, 0.5, 1 and 2 times the recommended rate. Simulated rainfall was applied at intensities of 64, 102, and 140 mm h-1; and the depths of …