Physical Sciences and Mathematics Commons^™

Dynamic Service Matchmaking Among Agents In Open Information Environments, Katia Sycara, Matthias Klusch, Seth Widoff, Jianguo Lu

Computer Science Publications

No abstract provided.

Even Subgraphs Of A Graph, Hong-Jian Lai, Zhi-Hong Chen

Scholarship and Professional Work - LAS

No abstract provided.

1999 Platte River Basin Ecosystem Symposium Proceedings

Water Current Newsletter

No abstract provided.

Kriging Puerto Rico Rainfall, Gary B. Hughes

Statistics

In Earth science research, climatic conditions can have significant effects on dynamic processes. For example, the growth of forests is affected by temperature, rainfall and other climatic variables. However, these climate parameters are rarely measured at the forest stands whose growth is being investigated. The climate conditions are measured at nearby weather stations, though, and it is a common approach to use the weather station data to ‘predict’ the climate at the study site

A Sheaf Theoretic Approach To Consciousness, Goro Kato, Daniele C. Struppa

Mathematics

A new fundamental mathematical model of consciousness based on category theory is presented. The model is based on two philosophical-theological assumptions: a) the universe is a sea of consciousness, and b) time is multi-dimensional and non-linear.

A Unifying Framework Supporting The Analysis And Development Of Safe Regression Test Selection Techniques, John Bible, Gregg Rothermel

CSE Technical Reports

Safe regression test selection (RTS) techniques let software testers reduce the number of test cases that need to be rerun to revalidate new versions of software, while ensuring that no fault-revealing test case (in the existing test suite) is excluded. Most previous work on safe regression test selection has focused on specific safe RTS algorithms, rather than addressing the theoretical foundations of safe RTS techniques in general. In this paper, we present a unifying framework for safe RTS that supports the analysis and development of safe RTS techniques. We show that every safe RTS technique is founded on a regression …

Empirical Computation Of Reject Ratio In Vlsi Testing, Shashank K. Mehta, Sharad C. Seth

CSE Conference and Workshop Papers

Among significant components of testing cost are testlength, reject ratio, and lost-yield. In this paper a new approach is proposed to estimate the reject ratio. The empirical model is based on test-data properties that are believed to be invariant for a wide range of manufacturing technologies and types of tests. The analysis is carried out entirely in terms of the device test data, as might be available from wafer probe. Experimental results demonstrate robustness of the model.

The Effect Of Carrier Gas Pressure On Vapor Phase Nucleation Experiments Using A Thermal Diffusion Cloud Chamber, D. Kane, S. P. Fisenko, M. Rusyniak, M. S. El-Shall

Chemistry Publications

Recent measurements of critical supersaturations for the vapor phase homogeneous nucleation of several substances using a diffusion cloud chamber technique exhibit a dependence on the pressure of the carrier gas used in the experiments. A model of droplet growth and motion in a diffusion cloud chamber, combined with the density and temperature profiles of the chamber is presented to explain the pressure dependent results. The model demonstrates that at higher carrier gas pressures the growth of the droplets is retarded and the optical scattering signal from the particles is reduced. It is concluded that the observed effect may not result …

Cooperative Text And Line Art Extraction From A Topographic Map, Luyang Li, George Nagy, Ashok Samal, Sharad C. Seth, Yihong Xu

CSE Conference and Workshop Papers

The black layer is digitized from a USGS topographic map digitized at 1000 dpi. The connected components of this layer are analyzed and separated into line art, text, and icons in two passes. The paired street casings are converted to polylines by vectorization and associated with street labels from the character recognition phase. The accuracy of character recognition is shown to improve by taking account of the frequently occurring overlap of line art with street labels. The experiments show that complete vectorization of the black line-layer bitmap is the major remaining problem.

Comparison Of Scalable Key Distribution Schemes For Secure Group Communication, Lakshminath R. Dondeti, Sarit Mukherjee, Ashok Samal

CSE Conference and Workshop Papers

Scalable secure key distribution is the most important feature of a scalable secure group communication protocol. Most of the existing scalable secure group communication protocols are based on a hierarchical key distribution tree. These schemes can be classified as hierarchical node based schemes and hierarchical key based schemes. In this paper; we compare recently proposed hierarchical key distribution schemes through simulation using real-life multicast group membership traces. Our simulations show that hierarchical node based approaches better distribute encryption cost among the entities of a multicast group. However hierarchical node based schemes “trust” internal nodes of a key distribution tree. We …

Guide For Developing Integrated Aquatic Vegetation Management Plans In Oregon, Maribeth Gibbons, Mark Rosenkranz, Harry L. Gibbons, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

This manual focuses on controlling nuisance aquatic plants, occurring in Oregon lakes. To use this manual, it is necessary to distinguish between an aquatic plant problem, and a water quality enrichment problem that typically results in excessive algae production (See Box this page). The most serious type of aquatic plant problem is caused by invasion of a waterbody by a non-native species. Non-native weed invaders may flourish in suitable conditions and degrade habitat and other beneficial uses. The biology and ecology of weeds allows them to fluorish under a wide range of conditions. Nutrient enrichment is not a prerequisite for …

1999 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

Fluctuation Properties Of Precipitation. Part Iv: Finescale Clustering Of Drops In Variable Rain, A. R. Jameson, Alexander Kostinski, A Kruger

Department of Physics Publications

In recent studies it is shown that in variable rain the spatial distribution of drops is not Poissonian. However, these past studies were limited to 1-min drop counts, which likely correspond to spatial scales of a few hundred to several hundreds of meters.

In this work results based on 1-s drop counts using a video disdrometer are reported. It is shown that the clustering of raindrops previously found during intervals of 1 min also occurs during 1 s as well in convective rain. These latter temporal scales likely correspond to spatial features having dimensions from only a few to tens …

The Weddell Sea Region: An Important Precipitation Channel To The Interior Of The Antarctic Ice Sheet As Revealed By Glaciochemical Investigation Of Surface Snow Along The Longest Trans-Antarctic Route, Qin Dahe, Paul Andrew Mayewski, Ren Jiawen, Xiao Cunde, Sun Junying

Earth Science Faculty Scholarship

Glaciochemical analysis of surface snow samples, collected along a profile crossing the Antarctic ice sheet from the Larsen Ice Shelf, Antarctic Peninsula, via the Antarctic Plateau through South Pole, Vostok and Komsomolskaya to Mirny station (at the east margin of East Antarctica), shows that the Weddell Sea region is an important channel for air masses to the high plateau of the Antarctic ice sheet (>2000 m a.s.l.). This opinion is supported by the following. (1) The fluxes of sea-salt ions such as Na⁺, Mg²⁺ and Cl⁻ display a decreasing trend from the west to the …

Seasonal Variations Of Glaciochemical, Isotopic And Stratigraphic Properties In Siple Dome (Antarctica) Surface Snow, K. J. Kreutz, Paul Andrew Mayewski, M. S. Twickler, S. I. Whitlow, J. W.C. White, C. A. Shuman, C. F. Raymond, H. Conway, J. R. Mcconnell

Earth Science Faculty Scholarship

Six snow-pit records recovered from Siple Dome, West Antarctica, during 1994 are used to study seasonal variations in chemical (major ion and H2O2), isotopic (deuterium) and physical stratigraphic properties during the 1988-94 period. Comparison of dD measurements and satellite-derived brightness temperature for the Siple Dome area suggests that most seasonal dD maxima occur within ±4 weeks of each 1 January. Several other chemical species (H2O2, non-sea-salt (nss) SO42-, methanesulfonic acid and NO3-) show coeval peaks with dD, together providing an accurate method for identifying summer accumulation. Sea-salt-derived species generally peak during winter/spring, but episodic input is noted throughout some years. …

Climatological Significance Of Δ18O In Precipitation And Ice Cores: A Case Study At The Head Of The Ürütnqi River, Tien Shan, China, Hou Shugui, Qin Dahe, Paul Andrew Mayewski, Yang Qinzhao, Ren Jiawen, Li Zhongqin, Xiao Cunde

Earth Science Faculty Scholarship

Stable-oxygen-isotope ratios (δ¹⁸O) collected from the headwaters of the Ürümqi river, Tien Shan, China, were used to test the relationship between δ¹⁸O temporal relationship is found between δ¹⁸O monthly averages which remove synoptic-scale influences such as changes in condensation level, condensation temperature and moisture sources (Yao and others, 1996). Linear fits as high as 0.95‰°C^-1 for precipitation events and 1.23‰°C^-1 for monthly averages are found. Although the δ¹⁸O (∼2 km from the precipitation sampling site) decreased dramatically compared to the precipitation samples , the ice-core records of annually averaged δ …

Data Fusion For Use Of Passive Microwave Data In Operational Sea-Ice Monitoring, Kim Partington, Mary-Ruth Keller, Paul Seymour, Cheryl Bertoia

United States Department of Commerce: Staff Publications

A new SSM/I algorithm is described that is based on near real-time data fusion with portions of operational ice charts derived from RADARSAT, OLS or AVHRR data. The aim of this is to enable parts of the ice chart where there is no cloud-free imagery or SAR data to be completed using an SSM/I algorithm that is tuned to the region and time associated with the ice chart. The algorithm is a linear combination of partial concentrations from the NASA Team and Bootstrap algorithms together with lower variance principal components of SSM/I data. The algorithm is designed for near real …

Hunting And Social Behaviour Of Leopard Seals (Hydrurga Leptonyx) At Seal Island, South Shetland Islands, Antarctica, Lisa M. Hiruki, Michael K. Schwartz, Peter L. Boveng

United States Department of Commerce: Staff Publications

The hunting behavior of leopard seals Hydrurga leptonyx was monitored opportunistically at Seal Island, South Shetland Islands, during the austral summers from 1986/87 to 1994/95. Leopard seals used several methods to catch Antarctic fur seal pups Arctocephalus gazella and chinstrap penguins Pygoscelis antarctica, and individuals showed different hunting styles and hunting success. One to two leopard seals per year were responsible for an average of 60% of observed captures of fur seal pups. Leopard seals preyed on penguins throughout the summer, but preyed on fur seal pups only between late December and mid-February. Hunting behavior differed significantly between different …

Sensitivity Of Fish Embryos To Weathered Crude Oil: Part Ii. Increased Mortality Of Pink Salmon (Oncorhynchus Gorbuscha) Embryos Incubating Downstream From Weathered Exxon Valdez Crude Oil, Ron A. Heintz, Jeffrey W. Short, Stanley D. Rice

United States Department of Commerce: Staff Publications

We incubated pink salmon embryos under three exposure conditions, direct contact with oil-coated gravel, effluent from oil-coated gravel, and direct contact with gravel coated with very weathered oil (VWO). Embryo mortalities and polynuclear aromatic hydrocarbon (PAH) accumulation in embryo tissues during the direct-contact and effluent exposure experiments were not significantly different, indicating that PAH accumulation was mediated by aqueous transport. Mortality rates for embryos exposed initially to a total PAH concentration (TPAH) of 1.0 ppb were significantly higher than controls when the PAH were derived from VWO. The same aqueous TPAH concentration failed to increase mortality rates when the PAH …

Lack Of Time-Delay Robustness For Stabilization Of A Structural Acoustics Model, George Avalos, Irena Lasiecka, Richard Rebarber

Department of Mathematics: Faculty Publications

In this paper we consider a natural robustness question for a model for structural acoustics. This model, which has been of great interest in recent years, is represented by a wave equation in R^2 coupled to a Kelvin--Voigt beam; the coupling is natural physically, and is represented mathematically by highly unbounded operators. We assume that the observation consists of point evaluation of the beam position, the beam velocity, and the wave velocity. We are interested in the effect of arbitrarily small delays in the feedback loop on a controller that uses these observations. We show that it is not possible …

A Value-Belief-Norm Theory Of Support For Social Movements: The Case Of Environmentalism, Paul C. Stern, Thomas Dietz, Troy D. Abel, Greg Guagnano, Linda Kalof

College of the Environment on the Peninsulas Publications

We present a theory of the basis of support for a social movement. Three types of support (citizenship actions, policy support and acceptance, and personal-sphere behaviors that accord with movement principles) are empirically distinct from each other and from committed activism. Drawing on theoretical work on values and norm-activation processes, we propose a value-belief-norm (VBN) theory of movement support. Individuals who accept a movement's basic values, believe that valued objects are threatened, and believe that their actions can help restore those values experience an obligation (personal norm) for pro-movement action that creates a predisposition to provide support; the particular type …

Environmental Technology Transfer And Foreign Investment : Factors Impacting Environmental Protection In A Transition-Era Cuba, Aldo M. Leiva

Institute for Cuban & Cuban-American Studies Occasional Papers

No abstract provided.

Numerical Simulations Of Fe Ii Emission Spectra, E. M. Verner, D. A. Verner, K. T. Korista, Jason W. Ferguson, F. Hamann, Gary J. Ferland

Physics and Astronomy Faculty Publications

This paper describes the techniques that we have used to incorporate a large-scale model of the Fe⁺ ion and resulting Fe IIemission into CLOUDY, a spectral synthesis code designed to simulate conditions within a plasma and model the resulting spectrum. We describe the numerical methods we use to determine the level populations, mutual line overlap fluorescence, collisional effects, and the heating-cooling effects of the atom on its environment. As currently implemented, the atom includes the lowest 371 levels (up to 11.6 eV) and predicts intensities of 68,635 lines. We describe our data sources, which include the most recent transition …

Lime Rate Adjustments Based On Rnv And Depth, William O. Thom

Soil Science News and Views

Agricultural limestone quality is measured by its neutralizing value and fineness of grind. Neutralizing value is determined by calcium carbonate equivalent (CCE). The higher the CCE, the greater the limestone’s ability to neutralize soil acidity. Reaction rate in the soil is affected by fineness of grind, with finer materials reacting faster with a soil to increase pH. Methods have been developed to calculate efficiency factors that involve using both CCE and material fineness. Regardless of the aglime material used, when the same amount of effective neutralizing material is applied and mixed thoroughly with the soil, the pH change in the …

Subsoiling Of No-Tilled Corn, Lloyd W. Murdock

Soil Science News and Views

No-tillage corn production has become very popular in Kentucky because of the advantages it offers producers. Currently, over half of the corn in Kentucky is planted by this method and even a higher percentage is no-till planted on erodible lands. Because of this, many fields have received little tillage in the last 10 to 20 years. Many producers wonder if soil compaction increases with time on these long-term no-tilled fields due to annual trafficking by heavy equipment. Subsoiling implements have become available that allow subsurface tillage while preserving the surface mulch layer. This practice allows for continued no-till planting while …

No Tillage Use For Crop Production In Kentucky Counties In 1998, Gerald R. Haszler

Soil Science News and Views

For the past several years, we have reported the status of no~tillage adoption in Kentucky counties. Now, CTICt has published the results for 1998. In 1994, 44% of all crops were produced under no tillage in Kentucky, whereas in 1996, that figure had reached 51 % . In 1997, it dropped to 48% and remains at 48% for 1998. Results for the leading no-till states for 1994, 1996, 1997 and 1998 are shown in Table 1. The percentage of major grain crops (com, soybeans and small grains) grown under no tillage in Kentucky are shown by county in Figure 1. …

Ground-Water Quality In Kentucky: Nitrate-Nitrogen, Philip G. Conrad, Daniel I. Carey, James S. Webb, James S. Dinger, Matthew J. Mccourt

Information Circular--KGS

No abstract provided.

Leading Charm In Hadron-Nucleus Interactions In The Intrinsic Charm Model, Thomas D. Gutierrez, R. Vogt

Physics

Leading charm hadrons produced in hadron-nucleus interactions cannot be adequately described within the parton fusion model. Recent results on charm baryon production in ∑-A interactions at 330 GeV with the WA89 detector disagree with fusion predictions. Intrinsic heavy quark pairs in the ∑- (dds) wavefunction provide a simple mechanism for producing fast charm hadrons. We calculate leading charm baryon production from ∑-, ∏- and p projectiles in a two component model combining parton fusion with intrinsic charm. Final state D-, ∑n_cn⁰, ≡n_cn⁺, and ∧n_cn⁺ dσ/dxn_{F …}

Reproduction And Health Of A Beaver (Castor Canadensis) Population In Prince William County, Virginia, Timothy R. Brophy, Carl H. Ernst

Faculty Publications and Presentations

Reproduction and health were studied in a beaver (Castor canadensis) population from Prince William County, Virginia during 1998. Copulating beavers were observed in Quantico Creek at Prince William Forest Park on 22 January. Seven females from Quantico Marine Base were trapped between January and May, sacrificed, and dissected. Those reproductively active weighed over 39 pounds (17.7 kg) and were trapped before 1 March. Mean litter size based on counts of corpora lutea was 4.80 young (3-7); however, litter size based on the number of embryos present was only 2.75 (1-3), comparable to most others reported in the literature. Five of …

An Iron-Based Ecosystem Model Of The Central Equatorial Pacific, Carrie L. Leonard, Charles R. Mcclain, Ragu Murtugudde, Eileen E. Hofmann, Lawrence W. Harding Jr.

CCPO Publications

The central and eastern equatorial Pacific region is characterized by lower than expected phytoplankton biomass and primary production given the relatively high ambient nitrate concentrations. These unusual conditions have spawned several field programs and laboratory experiments to determine why this high nitrate-low chlorophyll pattern persists in this region. To synthesize the results from these field programs, as well as providing additional evidence in support of the iron hypothesis, we developed a one-dimensional, nine-component ecosystem model of 0 degrees N 140 degrees W. The model components include two phytoplankton size fractions, two zooplankton size fractions, two detrital size fractions, dissolved iron, …