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2000

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Full-Text Articles in Physical Sciences and Mathematics

The Virginia Wetlands Report Vol. 15, No. 2, Virginia Institute Of Marine Science Jul 2000

The Virginia Wetlands Report Vol. 15, No. 2, Virginia Institute Of Marine Science

Virginia Wetlands Reports

  • Grass Shrimp. Walter I. Priest, III
  • Book Review Seashore Chronicles: Three Centuries of the Virginia Barrier Islands. Anne Newsom
  • Grass Shrimp. Walter I. Priest, III
  • A New Land Cover Data Set Now Available For Virginia’s Tributaries. Marcia Berman
  • DEQ Implementing Nontidal Wetlands Protection Mandate. Ellen Gilinsky
  • Sago Palm. Pam Mason


Sedimentologic And Paleogeomorphologic Character Of The Western Beteiha Plain, Israel, Laura Baker Jul 2000

Sedimentologic And Paleogeomorphologic Character Of The Western Beteiha Plain, Israel, Laura Baker

Student Work

The geographical problem addressed in this study was to reconstruct the paleogeography of the western Beteiha Plain, located between Bethsaida and the Sea of Galilee and determine its sedimentologic and paleogeomorphologic character. Grain size analysis of sediments, along with sediment color was used to reconstruct the landscape and identify areas such as estuaries or lagoons.

Sediment samples were collected throughout the Beteiha Plain at selected locations. Excavation and collection was accomplished with hand-driven core equipment and backhoe trenches.

The multidisciplinary approach used in this project included fieldwork for sediment collection, laboratory analysis for the production of the data necessary to …


The Climatic Impact Of La Niña-Related Droughts In Entre Rios (Argentina), Alicia E. Codromaz De Rojas Jul 2000

The Climatic Impact Of La Niña-Related Droughts In Entre Rios (Argentina), Alicia E. Codromaz De Rojas

Drought Network News (1994-2001)

The National Institute of Tecnologia Agropecuaria (INTA) at Parana, Entre Rios (Argentina), has a farming experimental station (E.E.A.) located at 31.5°S and 60.31°W, 110m above sea level. A meteorological observatory has existed at the site since 1934.

The region has a temperate humid climate and receives an average annual rainfall total of 1,000 mm. Distribution is monsoonal, with October–April rains accounting for 73% of the annual total.

Since August 1998, the area has been affected by La Niña, and experts expected the conditions of the cold episode to persist into 2000. The La Niña event in the humid Pampean region …


Announcements: Summer 2000 Jul 2000

Announcements: Summer 2000

Drought Network News (1994-2001)

Contents:

Disaster Management Workshops

Fifth Annual Conference on Crises and Disasters Management

DROUGHT 2000 Conference: Impacts, Policy, and Technology

16th Annual International Conference on Contaminated Soils, Sediments and Water


Conclusions And Recommendations From The Central And Eastern European Workshop On Drought Mitigation Jul 2000

Conclusions And Recommendations From The Central And Eastern European Workshop On Drought Mitigation

Drought Network News (1994-2001)

The importance of prevention and planning in drought mitigation was the impetus for the Central and Eastern European Workshop on Drought Mitigation, held April 12–15, 2000, in Budapest-Felsoőgöd, Hungary. The workshop was organized and sponsored by several Hungarian agencies: the Ministry of Agriculture and Rural Development; Ministry for Environment; Ministry of Transport, Communication and Water Management; Research and Development Division of the Ministry of Education; and Hungarian Meteorological Service. The United Nations Convention to Combat Desertification (UNCCD), Food and Agriculture Organization (FAO), United Nations Environment Programme (UNEP), World Meteorological Organization (WMO), European Commission Joint Research Centre (EC JRC–ISPRA), European Regional …


India’S Arid Region And The Current Drought, Pratap Narain, K. D. Sharma, A. S. Rao, D. V. Singh, B. K. Mathur, Usha Rani Ahuja Jul 2000

India’S Arid Region And The Current Drought, Pratap Narain, K. D. Sharma, A. S. Rao, D. V. Singh, B. K. Mathur, Usha Rani Ahuja

Drought Network News (1994-2001)

We recently surveyed some of the drought-affected areas (Figure 1) in the Indian arid region in a publication entitled “Strategy to Combat Drought and Famine in the Indian Arid Zone.” This article is a summary of the report.

The present drought in the arid and semiarid regions of India is due to the cumulative effect of inadequate rainfall during 1997–99. Twelve states in India are in the grip of severe drought, with Rajasthan, Gujarat, Andhra Pradesh, and Madhya Pradesh (Table 1) being the most affected. The Indian arid zone encompasses 32 million ha and is highly prone to droughts and …


The Drought In Chile And La Niña, Juan Quintana Jul 2000

The Drought In Chile And La Niña, Juan Quintana

Drought Network News (1994-2001)

Precipitation is one of the climatic elements most affected by the presence of La Niña in Chile. An important precipitation deficit begins during La Niña events, from latitude 45°S to the north. This deficit prevails most of the year, with winter (April–September) being most vulnerable to these anomalies. The central region of Chile (30°S to 40°S) has negative anomalies, with precipitation values 35% to 100% below the climatologic annual average. These rain deficiencies in Chile are determined by the persistence of anomalies of anticyclonal circulation of middle and subtropical latititudes and an area of anomalies of cyclonic circulation in the …


Talking Imperative For Grieving Farmers, Others, Cheryl Alberts Jul 2000

Talking Imperative For Grieving Farmers, Others, Cheryl Alberts

Drought Network News (1994-2001)

Farmers who are losing their livelihoods to the drought shouldn’t be surprised to feel depressed or angry, and neither should people around them. After all, these farmers are suffering a very real loss and they are grieving.

Farmers who lose a crop in many ways will react as have people who have lost loved ones, said John DeFrain, family and community development specialist at the University of Nebraska here. That is, they go into shock, denial and anger, and not necessarily in that order.

The loss of a crop means a loss of time, expenses, identity and, in some cases, …


From The Director: Summer 2000, Donald A. Wilhite Jul 2000

From The Director: Summer 2000, Donald A. Wilhite

Drought Network News (1994-2001)

We had a fairly good response to the call in the previous issue of Drought Network News for readers to receive future issues online. I would encourage more of you to consider this option, as it will save distribution costs and expedite receipt of the newsletter. If you are willing to receive the newsletter electronically, please contact Kim Klemsz (kklemsz2@unl.edu). Our plan is to notify you via e-mail when each new issue of Drought Network News is available. Back issues of Drought Network News are also available online.

At this writing, I am making final preparations for the Expert Group …


Carbon Nanotube-Based Nonvolatile Random Access Memory For Molecular Computing, Thomas Rueckes, Kyoungha Kim, Ernesto Joselevich, Greg Y. Tseng, Chin Li Cheung, Charles M. Lieber Jul 2000

Carbon Nanotube-Based Nonvolatile Random Access Memory For Molecular Computing, Thomas Rueckes, Kyoungha Kim, Ernesto Joselevich, Greg Y. Tseng, Chin Li Cheung, Charles M. Lieber

Barry Chin Li Cheung Publications

A concept for molecular electronics exploiting carbon nanotubes as both molecular device elements and molecular wires for reading and writing information was developed. Each device element is based on a suspended, crossed nanotube geometry that leads to bistable, electrostatically switchable ON/OFF states. The device elements are naturally addressable in large arrays by the carbon nanotube molecular wires making up the devices. These reversible, bistable device elements could be used to construct nonvolatile random access memory and logic function tables at an integration level approaching 1012 elements per square centimeter and an element operation frequency in excess of 100 gigahertz. The …


Modelling The Dynamics Of Abyssal Equator-Crossing Currents, P. F. Choboter, G. E. Swaters Jul 2000

Modelling The Dynamics Of Abyssal Equator-Crossing Currents, P. F. Choboter, G. E. Swaters

Mathematics

No abstract provided.


Dimensionality Reduction Using Genetic Algorithms, Michael L. Raymer, William F. Punch, Erik D. Goodman, Leslie A. Kuhn, Anil K. Jain Jul 2000

Dimensionality Reduction Using Genetic Algorithms, Michael L. Raymer, William F. Punch, Erik D. Goodman, Leslie A. Kuhn, Anil K. Jain

Kno.e.sis Publications

Pattern recognition generally requires that objects be described in terms of a set of measurable features. The selection and quality of the features representing each pattern affect the success of subsequent classification. Feature extraction is the process of deriving new features from original features to reduce the cost of feature measurement, increase classifier efficiency, and allow higher accuracy. Many feature extraction techniques involve linear transformations of the original pattern vectors to new vectors of lower dimensionality. While this is useful for data visualization and classification efficiency, it does not necessarily reduce the number of features to be measured since each …


Stochastic Systems With Memory: Theory, Examples And Applications (Postgraduate Seminar, University Of Central Venezuela), Salah-Eldin A. Mohammed Jul 2000

Stochastic Systems With Memory: Theory, Examples And Applications (Postgraduate Seminar, University Of Central Venezuela), Salah-Eldin A. Mohammed

Miscellaneous (presentations, translations, interviews, etc)

No abstract provided.


Fluid Flow In Micro-Channels: A Stochastic Approach, Hilda Marino Black Jul 2000

Fluid Flow In Micro-Channels: A Stochastic Approach, Hilda Marino Black

Doctoral Dissertations

In this study free molecular flow in a micro-channel was modeled using a stochastic approach, namely the Kolmogorov forward equation in three dimensions. Model equations were discretized using Central Difference and Backward Difference methods and solved using the Jacobi method. Parameters were used that reflect the characteristic geometry of experimental work performed at the Louisiana Tech University Institute for Micromanufacturing.

The solution to the model equations provided the probability density function of the distance traveled by a particle in the micro-channel. From this distribution we obtained the distribution of the residence time of a particle in the micro-channel. Knowledge of …


Spin Fluctuations In Nearly Magnetic Metals From Ab Initio Dynamical Spin Susceptibility Calculations: Application To Pd And Cr95v5, J. B. Staunton, J. Poulter, B. Ginatempo, E. Bruno, Duane D. Johnson Jul 2000

Spin Fluctuations In Nearly Magnetic Metals From Ab Initio Dynamical Spin Susceptibility Calculations: Application To Pd And Cr95v5, J. B. Staunton, J. Poulter, B. Ginatempo, E. Bruno, Duane D. Johnson

Duane D. Johnson

We describe our theoretical formalism and computational scheme for making ab initio calculations of the dynamic paramagnetic spin susceptibilities of metals and alloys at finite temperatures. Its basis is time-dependent density functional theory within an electronic multiple scattering, imaginary time Green function formalism. Results receive a natural interpretation in terms of overdamped oscillator systems making them suitable for incorporation into spin fluctuation theories. For illustration we apply our method to the nearly ferromagnetic metal Pd and the nearly antiferromagnetic chromium alloy Cr95V5. We compare and contrast the spin dynamics of these two metals and in each case identify those fluctuations …


10. Dietrich Braun, Otto Vogl Jul 2000

10. Dietrich Braun, Otto Vogl

Otto Vogl

No abstract provided.


Effects Of Planetary Wave-Breaking On The Seasonal Variation Of Total Column Ozone, Terrence R. Nathan, Eugene C. Cordero, Long Li, Donald J. Wuebbles Jul 2000

Effects Of Planetary Wave-Breaking On The Seasonal Variation Of Total Column Ozone, Terrence R. Nathan, Eugene C. Cordero, Long Li, Donald J. Wuebbles

Faculty Publications, Meteorology and Climate Science

The effects of planetary wave breaking on the seasonal variation of total column ozone are investigated using a zonally averaged chemical-radiative-transport model of the atmosphere. The planetary wave breaking effects of zonal wavenumbers k=1 and k=2 are significant in the middle latitude stratosphere during Northern Hemisphere (NH) winter, whereas only wave k=1 is important during Southern Hemisphere (SH) winter. The mixing and induced meridional circulation due to the planetary wave breaking increases the seasonal variation of total column ozone in NH (SH) middle latitudes by ∼20% (∼10%).


The Probe, Issue 211 - July/August 2000 Jul 2000

The Probe, Issue 211 - July/August 2000

The Probe: Newsletter of the National Animal Damage Control Association

CONTENTS:
NADCA Election Results Announced
Editor's Farewell
CALENDAR OF UPCOMING EVENTS
Bill Clay to Head Wildlife Services
Editors Farewell
Parasite Makes Rats More Vulnerable to Cats Crazed Beaver Terrorizes Farm
Mounties Don't Like Shooting Bears
Book Review: "Mammal Trapping"
PETA Attacks Wyoming License Plates


Santa Clara Magazine, Volume 42 Number 1, Summer 2000, Santa Clara University Jul 2000

Santa Clara Magazine, Volume 42 Number 1, Summer 2000, Santa Clara University

Santa Clara Magazine

8 - ATTACK OF THE KILLER TOMATOES? By Miriam Schulman. Beyond the hype of the headlines, there are no simple answers to the ethical questions raised by genetically modified food.

14 - BRAVE NEW WORLD By Tamara Straus. Now the lawyers want inside your head as they struggle to answer, "Who owns an idea?" Just the mere question is changing the face of legal education.

18 - THE GREAT GRADE GIVEAWAY By Jeff Zorn. Today's grades don't mean jack. So says one Santa Clara professor in this memoir and commentary on the evils of modern day grade inflation.

22 - …


A New Fixed-Point Theorem For Logic Programming Semantics, Anthony K. Seda, Pascal Hitzler Jul 2000

A New Fixed-Point Theorem For Logic Programming Semantics, Anthony K. Seda, Pascal Hitzler

Computer Science and Engineering Faculty Publications

We present a new fixed-point theorem akin to the Banach contraction mapping theorem, but in the context of a novel notion of generalized metric space, and show how it can be applied to analyse the denotational semantics of certain logic programs. The theorem is obtained by generalizing a theorem of Priess-Crampe and Ribenboim, which grew out of applications within valuation theory, but is also inspired by a theorem of S.G. Matthews which grew out of applications to conventional programming language semantics. The class of programs to which we apply our theorem was defined previously by us in terms of operators …


Multiparty Key Agreement Protocols, J. Pieprzyk, C. H. Li Jul 2000

Multiparty Key Agreement Protocols, J. Pieprzyk, C. H. Li

Faculty of Informatics - Papers (Archive)

A class of multiparty key agreement protocols based on secret sharing is presented. The trust infrastructure necessary to achieve the intended security goals is discussed.


Differentiated Service Performance Analysis, L. V. Nguyen, A. Eyers, Joe F. Chicharo Jul 2000

Differentiated Service Performance Analysis, L. V. Nguyen, A. Eyers, Joe F. Chicharo

Faculty of Informatics - Papers (Archive)

Differentiated service (DiffServ) has been proposed as an alternative for Integrated service. It aims to provide the same service to a group of flows that have similar quality of service requirements. Assured forwarding (AF) and expedited forwarding (EF) are two proposals for DiffServ provision. We present a performance analysis of an N drop-precedences threshold dropping (TD) queue, which is one of the proposed mechanisms for AF. In this analysis, traffic flows are assumed Poisson with exponentially distributed service time. We present simulation results that verify the analysis. This paper is an extension of the work attempted by Bolot et al. …


Connection Admission Control In Micro-Cellular Multi-Service Mobile Networks, R. S. Raad, E. Dutkiewicz, Joe F. Chicharo Jul 2000

Connection Admission Control In Micro-Cellular Multi-Service Mobile Networks, R. S. Raad, E. Dutkiewicz, Joe F. Chicharo

Faculty of Informatics - Papers (Archive)

This paper investigates the use of fixed bandwidth reservation for multi-service mobile networks. In particular it extends previous fixed multi-service network results to the mobile scenario and presents analytical and simulation results for new and handover call blocking probabilities. It also investigates the performance sensitivity to different traffic load ratios as well as the cell dwell time distribution.


Path Planning For Planar Articulated Robots Using Configuration Spaces And Compliant Motion, Elisha Sacks Jul 2000

Path Planning For Planar Articulated Robots Using Configuration Spaces And Compliant Motion, Elisha Sacks

Department of Computer Science Technical Reports

No abstract provided.


Scwds Briefs: Volume 16, Number 2 (July 2000) Jul 2000

Scwds Briefs: Volume 16, Number 2 (July 2000)

Southeastern Cooperative Wildlife Disease Study: Publications


• CWD and Human Health: “There currently is no evidence that Chronic Wasting Disease in Cervidae is transmitted to humans”…
• SCWDS recently completed the fieldwork of a research project to investigate the epidemiology of avian vacuolar myelinopathy (AVM), previously known as the Avian Brain Lesion Syndrome (ABLS).
• NIH Funds SCWDS Ehrlichiosis Study: Since 1985, three new tickborne zoonoses caused by bacteria in the genus Ehrlichia have been recognized in the United States. Human monocytotropic ehrlichiosis (HME) caused by E. chaffeensis occurs across a broad area of the eastern and south-central United States. HME is transmitted by lone star …


The University Of Nebraska At Omaha Center For Space Data Use In Teaching And Learning, Neal Grandgenett, Uno Aviation Institute Jul 2000

The University Of Nebraska At Omaha Center For Space Data Use In Teaching And Learning, Neal Grandgenett, Uno Aviation Institute

Faculty Books and Monographs

UNOAI Report 2000-4

Within the context of innovative coursework and other educational activities, we are proposing the establishment of a University of Nebraska at Omaha Center for the Use of Space Data in Teaching and Learning. This Center will provide an exciting and motivating process for educators at all levels to become involved in professional development and training which engages real life applications of mathematics, science, and technology. The Center will facilitate innovative courses (including online and distance education formats), systematic degree programs, classroom research initiatives, new instructional methods and tools, engaging curriculum materials, and various symposiums. It will involve …


Effects Of Planetary Wave-Breaking On The Seasonal Variation Of Total Column Ozone, Terrence R. Nathan, Eugene C. Cordero, Long Li, Donald J. Wuebbles Jul 2000

Effects Of Planetary Wave-Breaking On The Seasonal Variation Of Total Column Ozone, Terrence R. Nathan, Eugene C. Cordero, Long Li, Donald J. Wuebbles

Eugene C. Cordero

The effects of planetary wave breaking on the seasonal variation of total column ozone are investigated using a zonally averaged chemical-radiative-transport model of the atmosphere. The planetary wave breaking effects of zonal wavenumbers k=1 and k=2 are significant in the middle latitude stratosphere during Northern Hemisphere (NH) winter, whereas only wave k=1 is important during Southern Hemisphere (SH) winter. The mixing and induced meridional circulation due to the planetary wave breaking increases the seasonal variation of total column ozone in NH (SH) middle latitudes by ∼20% (∼10%).


666 Or 616 (Rev. 13,18), M. G. Michael Jul 2000

666 Or 616 (Rev. 13,18), M. G. Michael

Faculty of Informatics - Papers (Archive)

No abstract provided.


Direct Measurement Of Oscillations Between Degenerate Two-Electron Bound-State Configurations In A Rapidly Autoionizing System, Heider N. Ereifej, J. Greg Story Jul 2000

Direct Measurement Of Oscillations Between Degenerate Two-Electron Bound-State Configurations In A Rapidly Autoionizing System, Heider N. Ereifej, J. Greg Story

Physics Faculty Research & Creative Works

In this paper we report a direct observation of the oscillation between bound-state configurations in a rapidly autoionizing system. Calcium atoms were excited to a pure 4p3/2nd two-electron configuration using a 500-fsec laser pulse. The initial 4p3/2nd doubly excited state is energy degenerate with the 4p1/2n'd states and several continuum channels. Because of the short-pulse excitation, the initial state of the atom is not an energy eigenstate, but a nonstationary wave packet. As a result, oscillations between the two bound configurations were produced. These oscillations were measured by scanning the timing of a second …


Search For The Charged Higgs Boson In The Decays Of Top Quark Pairs In The EΤ And Μτ Channels At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Jul 2000

Search For The Charged Higgs Boson In The Decays Of Top Quark Pairs In The EΤ And Μτ Channels At √S =1.8 Tev, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

Top quark production offers the unique opportunity to search for a charged Higgs boson (H±), as the contribution from tH+b τ + νb can be large in extensions of the standard model. We use results from a search for top quark pair production by the Collider Detector at Fermilab (CDF) in the e τ +ET+jets and μ τ+ET+jets signatures to set an upper limit on the branching ratio of Ɓ (tH+b) in 106 pb-1 of data. The upper …