Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 69691 - 69720 of 78971

Full-Text Articles in Entire DC Network

Extending The Power And Capacity Of Constraint Satisfaction Networks, Tony R. Martinez, Xinchuan Zeng Jul 1999

Extending The Power And Capacity Of Constraint Satisfaction Networks, Tony R. Martinez, Xinchuan Zeng

Faculty Publications

This work focuses on improving the Hopfield network for solving optimization problems. Although much work has been done in this area, the performance of the Hopfield network is still not satisfactory in terms of valid convergence and quality of solutions. We address this issue in this work by combing a new activation function (EBA) and a new relaxation procedure (CR) in order to improve the performance of the Hopfield network. Each of EBA and CR has been individually demonstrated capable of substantially improving the performance. The combined approach has been evaluated through 20,000 simulations based on 200 randomly generated city …


The Robustness Of Relaxation Rates In Constraint Satisfaction Networks, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur Jul 1999

The Robustness Of Relaxation Rates In Constraint Satisfaction Networks, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur

Faculty Publications

Constraint satisfaction networks contain nodes that receive weighted evidence from external sources and/or other nodes. A relaxation process allows the activation of nodes to affect neighboring nodes, which in turn can affect their neighbors, allowing information to travel through a network. When doing discrete updates (as in a software implementation of a relaxation network), a goal net or goal activation can be computed in response to the net input into a node, and a relaxation rate can then be used to determine how fast the node moves from its current value to its goal value. An open question was whether …


Changing The Subject, Or, Would You Hire A Good Clarinet Teacher To Teach Your Child The Violin?, Jerome Dancis Jul 1999

Changing The Subject, Or, Would You Hire A Good Clarinet Teacher To Teach Your Child The Violin?, Jerome Dancis

Humanistic Mathematics Network Journal

No abstract provided.


Liming Of Vineyard Soils, Thomas J. Rice Jul 1999

Liming Of Vineyard Soils, Thomas J. Rice

Earth and Soil Sciences

Liming vineyard soils to increase soil pH and raise calcium levels has been practiced for centuries in the humid areas of the world where soils tend to be more acid. Today, liming is increasingly practiced in the semiarid central coast regions of California, where liming of vineyards was unheard of even a decade ago.
Past agricultural practices, such as the addition of sulfur, acid-forming nitrogen fertilizers, and organic soil amendments, have caused soil acidification. Previously, most of these lands were either open space, range lands, or planted to grain crops.
To avoid unnecessary expense and protect the soil from environmental …


Neural Networks And Structured Knowledge: Knowledge Representation And Reasoning, Franz J. Kurfess Jul 1999

Neural Networks And Structured Knowledge: Knowledge Representation And Reasoning, Franz J. Kurfess

Computer Science and Software Engineering

This collection of articles is the first of two parts of a special issue on "Neural Networks and Structured Knowledge." The contributions to the first part shed some light on the issues of knowledge representation and reasoning with neural networks. Their scope ranges from formal models for mapping discrete structures like graphs or logical formulae onto different types of neural networks, to the construction of practical systems for various types of reasoning. In the second part to follow, the emphasis will be on the extraction of knowledge from neural networks, and on applications of neural networks and structured knowledge to …


Art And Geometry: Proportion And Similarity, Catherine A. Gorini Jul 1999

Art And Geometry: Proportion And Similarity, Catherine A. Gorini

Humanistic Mathematics Network Journal

No abstract provided.


Analogic Thinking In Science And Math, Martha D. Patton Jul 1999

Analogic Thinking In Science And Math, Martha D. Patton

Humanistic Mathematics Network Journal

No abstract provided.


The Translocation Of Barramundi. A Discussion Paper., Makaira Pty Ltd Jul 1999

The Translocation Of Barramundi. A Discussion Paper., Makaira Pty Ltd

Fisheries Management Papers

There is recognisable economic benefit to the translocation of barramundi, but there is also a need to ensure the translocation will not adversely impact upon the genetic diversity, introduce disease or impact on the natural environment and biodiversity. This discussion paper has been prepared to provide information to assist in the assessment of the possible impact of translocation of barramundi into and within Western Australia, for the purposed of recreational stock enhancement, aquaculture development and domestic stocking. In contemplating the translocation any aquatic species, signigicant economic and social benefits must be balanced with biological and environmental risks; that is, the …


Fisheries Research Report No. 111 - Sea Temperature Variability Off Western Australia 1990 To 1994, Alan Pearce, Mark Rossbach, Marion Tait, Rhys Brown Jul 1999

Fisheries Research Report No. 111 - Sea Temperature Variability Off Western Australia 1990 To 1994, Alan Pearce, Mark Rossbach, Marion Tait, Rhys Brown

Fisheries Research Reports

Analysis of temperature data from coastal waters between Shark Bay and Cape Mentelle has shown the main features of temporal and spatial variability in temperature along the Western Australian coastline. Three distinct periods of variability emerge: the annual cycle (peak temperatures generally in January-February and troughs in July-August), a few-day (weatherrelated) cycle, and the diurnal pattern.

Summer temperatures range from 24° C (South Passage) to 19° C (Cape Mentelle), and winter temperatures from 21° C (South Passage) to 16° C (Marmion). Mean annual temperature ranges (winter minimum to summer maximum) are between 3° C (South Passage) and 7° C (Alkimos), …


The Probe, Issue 202 – July 1999 Jul 1999

The Probe, Issue 202 – July 1999

The Probe: Newsletter of the National Animal Damage Control Association

Bird Strike USA Meeting a Success -- Eugene LeBoeuf, Bird Strike Scientist, HQ Air Force Safety Center, KirtlandAFB, New Mexico, and Past President, NADCA
Position Available: Wildlife Biologist, JFK Airport
Hawk Starts Grass Fire
Juicy Fruit Gum Remedy Story Persists
Cambodian Artifacts Threatened by Bats
Predator Killings Planned: State Game Managers Target Cougars, Coyotes
Video review: "Cleaning Skulls for Pleasure or Profit" by Ken Carver, Maplewood, MN. VHS. Approx. 120 minutes. $19.95 postpaid.
House Backs Funding of Program That Targets Predators
Armadillos Considered Delicacies By Some; Leprosy Threat by Others


The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth Jul 1999

The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth

Faculty Publications

Published data and analyses from temperate and tropical aquatic systems are used to summarize knowledge about the potential impact of land-use alteration on the nitrogen biogeochemistry of tropical aquatic ecosystems, identify important patterns and recommend key needs for research. The tropical N-cycle is traced from pre-disturbance conditions through the phases of disturbance, highlighting major differences between tropical and temperate systems that might influence development strategies in the tropics. Analyses suggest that tropical freshwaters are more frequently N-limited than temperate zones, while tropical marine systems may show more frequent P limitation. These analyses indicate that disturbances to pristine tropical lands will …


Center For Sustainable Agricultural Systems Newsletter, July/August 1999 Jul 1999

Center For Sustainable Agricultural Systems Newsletter, July/August 1999

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

Contents:

Biotechnology Issues Discussed at NABC Meeting in Lincoln

University Role in Biotechnology: How Do We Sustain Food Production?

CSAS Issues Volumes 10 and 11

SARE Marketing Conference in Lincoln This November

September 10 is Deadline for NCR SARE Preproposals

Nebraska Legislative Bills Study Management and Help Beginning Farmers/Ranchers

Voluntary Program Will Boost Organic Exports

Canada Introduces National Standard for Organic Agriculture

Merrigan to Head USDA's Agricultural Marketing Service

Nominations Sought for Steward of the Land Award

Thanks and Farewell, Glen


Scwds Briefs: Volume 15, Number 2 (July 1999) Jul 1999

Scwds Briefs: Volume 15, Number 2 (July 1999)

Southeastern Cooperative Wildlife Disease Study: Publications

SCWDS BRIEFS
July 1999
1998 HD Summary
Hemorrhagic disease (HD)
EHD virus serotype 2 (EHDV-2)
Viral RNA
HD Virus Isolation Support
Epizootic hemorrhagic disease virus (EHDV)
Bluetongue Virus (BTV)
Cattle pulmonary artery endothelial (CPAE)
BHK21 cells
Recommendations for the Use of Lyme Disease Vaccine
Lyme disease
Drug Enforcement Administration (DEA)
Ketamine
Avian Brain Lesion Syndrome (ABLS)
Coot and Eagle Brain Lesion Syndrome (CEBLS)
Harold M. Smith -- 1942-1999


Challenges For Directors Of University Natural Science Museums, Hugh H. Genoways Jul 1999

Challenges For Directors Of University Natural Science Museums, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

Universities and natural science museums have a long, productive history; however, this has been an uneasy alliance in the United States at least since the 1880s. Decreasing resources and increasing expectations have made the position of all museum directors extremely difficult, but the situation for university natural science museum directors is probably the most complicated among these because they direct museums that are small administrative units within larger university organizations. Some of their challenges include conflict between museum and university missions, governance issues, relationship between director and the university administrator/board member, lack of understanding of museum functions, middle management role …


Bulletin 4369 - Ord River Irrigation Area - Kununurra Western Australia, Agriculture Western Australia Jul 1999

Bulletin 4369 - Ord River Irrigation Area - Kununurra Western Australia, Agriculture Western Australia

Bulletins 4000 -

The Ord River Irrigation Area (ORIA) in the Kimberley Province of Western Australia is the product of a bold and imaginative plan to develop part of the nation's tropical north for intensive agriculture by harnessing the waters of the Ord River. The principal features of the scheme are:

* A major storage reservoir formed by a dam constructed where the Ord River enters the Carr-Boyd Ranges, 160 kilometres south-east of Wyndham.

* A diversion dam, 50 kilometres further downstream, to raise the river level and divert water to be released from the major storage reservoir onto the irrigable lands.

* …


Zinc Speculation And Ligand Fluxes In Chesapeake Bay And Elizabeth River Pore Waters, Duncan Glover Byers Jul 1999

Zinc Speculation And Ligand Fluxes In Chesapeake Bay And Elizabeth River Pore Waters, Duncan Glover Byers

Chemistry & Biochemistry Theses & Dissertations

Presented here are the first data on the vertical concentrations, complexation, speciation, and fluxes of total dissolved zinc and zinc complexing ligands, and zinc speciation in sediment pore waters in the Chesapeake Bay and Elizabeth River, Virginia.

Sediment pore waters were collected in mid and southern Chesapeake Bay in November 1997 and in the Elizabeth River (Pinner's Point) in March, April, and July 1998. Flux experiments were conducted in Elizabeth River sediment cores in April and July 1998. [TDZn] and zinc complexation were determined using differential pulse anodic stripping voltammetry at a hanging mercury drop electrode (DPASV-HMDE).

[TDZn] in the …


Models For Molybdenum Coordination During The Catalytic Cycle Of Periplasmic Nitrate Reductase From Paracoccus Denitrificans Derived From Epr And Exafs Spectroscopy, Clive S. Butler, John M. Charnock, Brian Bennett, Heather J. Sears, Ann J. Reilly, Stuart J. Ferguson, C. David Garner, David J. Lowe, Andrew J. Thomson, Ben C. Berks, David J. Richardson Jul 1999

Models For Molybdenum Coordination During The Catalytic Cycle Of Periplasmic Nitrate Reductase From Paracoccus Denitrificans Derived From Epr And Exafs Spectroscopy, Clive S. Butler, John M. Charnock, Brian Bennett, Heather J. Sears, Ann J. Reilly, Stuart J. Ferguson, C. David Garner, David J. Lowe, Andrew J. Thomson, Ben C. Berks, David J. Richardson

Physics Faculty Research and Publications

The periplasmic nitrate reductase from Paracoccus denitrificans is a soluble two-subunit enzyme which binds two hemes (c-type), a [4Fe-4S] center, and a bis molybdopterin guanine dinucleotide cofactor (bis-MGD). A catalytic cycle for this enzyme is presented based on a study of these redox centers using electron paramagnetic resonance (EPR) and extended X-ray absorption fine structure (EXAFS) spectroscopies. The Mo(V) EPR signal of resting NAP (High g [resting]) has gav = 1.9898 is rhombic, exhibits low anisotropy, and is split by two weakly interacting protons which are not solvent-exchangeable. Addition of exogenous ligands to this resting …


1-Butaneboronic Acid Binding To Aeromonas Proteolytica Aminopeptidase:  A Case Of Arrested Development, Carin C. De Paola, Brian Bennett, Richard C. Holz, Dagmar Ringe, Gregory A. Petsko Jul 1999

1-Butaneboronic Acid Binding To Aeromonas Proteolytica Aminopeptidase:  A Case Of Arrested Development, Carin C. De Paola, Brian Bennett, Richard C. Holz, Dagmar Ringe, Gregory A. Petsko

Physics Faculty Research and Publications

Hydrolases containing two metal ions connected by a bridging ligand catalyze reactions important in carcinogensis, tissue repair, post-translational modification, control and regulation of biochemical pathways, and protein degradation. The aminopeptidase from Aeromonas proteolytica serves as a paradigm for the study of such bridged bimetallic proteases since its three-dimensional structure is known to very high resolution and its catalytic reaction is amenable to spectroscopic examination. Herein, we report the X-ray crystal structure at 1.9 Å resolution of AAP complexed with 1-butaneboronic acid (BuBA). This structure suggests that this complex represents a snapshot of the proteolytic reaction in an arrested form between …


Nitrate Reductase Activity, Nitrate Uptake And Iodine Speciation In The Marine Environment, Chin-Chang Hung Jul 1999

Nitrate Reductase Activity, Nitrate Uptake And Iodine Speciation In The Marine Environment, Chin-Chang Hung

OES Theses and Dissertations

The present method for the determination of new production (NP) by measuring the uptake of added 15NO3– suffers from a number of limitations. In an attempt to improve this situation, this research examined the possibility of estimating 15NO3– uptake by measuring the activity of nitrate reductase (NRA). In addition, because it has long been suspected that the biological reduction of IO3– to I– may be mediated by nitrate reductase (NR), this research investigated the ability of NR to catalyze the reduction of iodate to iodide.

An improved method for the determination …


Molecular Techniques Reveal Wide Phyletic Diversity Of Heterotrophic Microbes Associated With Discodermia Spp. (Porifera: Demospongiae), Jose V. Lopez, Peter J. Mccarthy, Kathleen E. Janda, Robin Willoughby, Shirley A. Pomponi Jun 1999

Molecular Techniques Reveal Wide Phyletic Diversity Of Heterotrophic Microbes Associated With Discodermia Spp. (Porifera: Demospongiae), Jose V. Lopez, Peter J. Mccarthy, Kathleen E. Janda, Robin Willoughby, Shirley A. Pomponi

Marine & Environmental Sciences Faculty Articles

Sponges are well known to harbor large numbers of heterotrophic microbes within their mesohyl. Studies to determine the diversity of these associated microbes have been attempted for only a few shallow water species. We cultured various microorganisms from several species of Discodermia collected from deep water using the 'Johnson-Sea-Link' manned submersibles, and characterised them by standard microbiological identification methods. Characterisation of a small proportion (ca. 10%) of the total and potential eubacterial isolate collection with molecular systematics techniques revealed a wide diversity of microbes. Phylogenetic analyses of 32 small subunit (SSU) 16S-like rRNA gene sequences from different micorbes indicated high …


Intermediate Species Possessing Bent Dna Are Present Along The Pathway To Formation Of A Final Tbp-Tata Complex, Kay M. Parkhurst, Robyn M. Richards, Michael Brenowitz, Lawrence J. Parkhurst Jun 1999

Intermediate Species Possessing Bent Dna Are Present Along The Pathway To Formation Of A Final Tbp-Tata Complex, Kay M. Parkhurst, Robyn M. Richards, Michael Brenowitz, Lawrence J. Parkhurst

Lawrence Parkhurst Publications

Binding of the TATA-binding protein (TBP) to the “TATA” sequences present in the promoters of eukaryotic class II genes is the first step in the sequential assembly of transcription pre-initiation complexes. Myriad structural changes, including severe bending of the DNA, accompany TBP-TATA complex formation. A detailed kinetic study has been conducted to elucidate the mechanistic details of TBP binding and DNA bending. The binding of Saccharomyces cerevisiae TBP to the adenovirus major late promoter (AdMLP) was followed in real-time through a range of temperatures and TBP concentrations using fluorescence resonance energy transfer (FRET) and stopped-flow mixing. The results of association …


High-Performance Liquid Chromatographic Separation Of Novel Atropic Α,Α-Disubstituted-Β-Amino Acids, Either On Different Β-Cyclodextrin-Bonded Phases Or As Their 1-Fluoro-2,4-Dinitrophenyl-5-L-Alanine Amide Derivatives, Gabriella Török, Antal Péter, Anne Gaucher, Michel Wakselman, Jean Paul Mazaleyrat, Daniel W. Armstrong Jun 1999

High-Performance Liquid Chromatographic Separation Of Novel Atropic Α,Α-Disubstituted-Β-Amino Acids, Either On Different Β-Cyclodextrin-Bonded Phases Or As Their 1-Fluoro-2,4-Dinitrophenyl-5-L-Alanine Amide Derivatives, Gabriella Török, Antal Péter, Anne Gaucher, Michel Wakselman, Jean Paul Mazaleyrat, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

The high-performance liquid chromatographic enantioresolution of free and N- and/or C-protected derivatives of (R, S)-2',1':1,2;1',2':3,4-dinaphthcyclohepta-1,3-diene-6-aminomethyl-6 -carboxylic acid (β2-Bin) by direct and indirect methods is reported. The direct separation was carried out on native and different derivatized β -cyclodextrin-bonded phases. The indirect resolution was achieved by applying pre-column derivatization with 1-fluoro-2,4-dinitrophenyl-5-L-alanine amide. The effects of different parameters such as the mobile phase composition and the structures of the compounds on the enantiomeric resolution are discussed.


Methylene-Only Subspectra In 13C Cpmas Using A New Double Quantum Filtering Sequence, Paola Rossi, Raju Subramanian, Gerard S. Harbison Jun 1999

Methylene-Only Subspectra In 13C Cpmas Using A New Double Quantum Filtering Sequence, Paola Rossi, Raju Subramanian, Gerard S. Harbison

Gerard S. Harbison Publications

Methodology for the assignment of 13C CPMAS spectra is still in its infancy. Previous methods of CPMAS spectral editing have utilized differences in the strength of the 13C–1H dipolar interaction or the rate and spin thermodynamics of crosspolarization from protons to carbon, to differentiate between quaternary, tertiary, and methylene carbons. We introduce a different approach, which is based on the fact that double-quantum coherence develops between the protons of a methylene group considerably faster than between most other proton spin pairs in an organic solid. We generate this coherence, filter it, convert it back to single …


Nebraska V. Wyoming: The End Or Collaboration?, Wendy Weiss, James Montgomery Jun 1999

Nebraska V. Wyoming: The End Or Collaboration?, Wendy Weiss, James Montgomery

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

13 pages.

Contains footnotes.


Platte River Endangered Species Partnership: Collaboration Or Coercion In Disguise, Dale Strickland Jun 1999

Platte River Endangered Species Partnership: Collaboration Or Coercion In Disguise, Dale Strickland

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

9 pages.


An Environmental Perspective On Collaboration In Large Ecosystem Restoration Processes, Daniel F. Luecke Jun 1999

An Environmental Perspective On Collaboration In Large Ecosystem Restoration Processes, Daniel F. Luecke

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

13 pages (includes illustration).

Contains 3 pages of references.


Indian Water Rights And The Snake River Basin Adjudication, Peter C. Monson Jun 1999

Indian Water Rights And The Snake River Basin Adjudication, Peter C. Monson

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

19 pages (includes map).


Priorities Of The States For Clean Water Act Reauthorization, J. David Holm Jun 1999

Priorities Of The States For Clean Water Act Reauthorization, J. David Holm

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

16 pages.


Agenda: Strategies In Western Water Law And Policy: Courts, Coercion And Collaboration, University Of Colorado Boulder. Natural Resources Law Center, University Of Colorado Boulder. Center Of The American West Jun 1999

Agenda: Strategies In Western Water Law And Policy: Courts, Coercion And Collaboration, University Of Colorado Boulder. Natural Resources Law Center, University Of Colorado Boulder. Center Of The American West

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

1 v. (various pagings) : ill., maps, charts ; 29 cm

Conference organizers, session moderators and/or speakers included University of Colorado School of Law professors Gary C. Bryner, James N. Corbridge, Jr., David H. Getches, Douglas S. Kenney, Lawrence J. MacDonnell, Kathryn M. Mutz and Charles F. Wilkinson

Includes bibliographical references

The event will examine the principal problem-solving strategies in western water law and policy: courts, coercion and collaboration. In addressing this broad range of strategies, the program will focus on national, west-wide and Colorado-specific issues.

Conference activities will commence with a free public program cosponsored by the Center of …


A Multilevel Secure Workflow Management System, Myong H. Kang, Judith N. Froscher, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller Jun 1999

A Multilevel Secure Workflow Management System, Myong H. Kang, Judith N. Froscher, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller

Kno.e.sis Publications

The Department of Defense (DoD) needs multilevel secure (MLS) workflow management systems to enable globally distributed users and applications to cooperate across classification levels to achieve mission critical goals. An MLS workflow management system that allows a user to program multilevel mission logic, to securely coordinate widely distributed tasks, and to monitor the progress of the workflow across classification levels is required. In this paper, we present a roadmap for implementing MLS workflows and focus on a workflow builder that is a graphical design tool for specifying such workflows.