Physical Sciences and Mathematics Commons^™

Evaluation Of Extent And Bioavailability Of Chromium Contamination Near An Abandoned Strip Mine, C. Appel, J. Stuckey, A. Cosley, R. Donald, C. Griffith, S. Lager, M. Perry, T. Ray, P. Smith

Earth and Soil Sciences

Chromium is a potentially toxic element to plants and animals commonly associated with serpentine and anthropogenic sources. An abandoned Cr strip-mine at US National Guard Camp SLO, CA containing serpentinitic parent material was tested for total and bioavailable Cr in the soil and overlying vegetation via US EPA Methods 3050a (Total Cr) and 1311 (Total Characteristic Leaching Procedure, TCLP) (US EPA, 1995), respectively. The analysis of total and bioavailable Cr was used to assess the risk of nearby surface and groundwater contamination and to evaluate the site’s need for remediation. In addition, trends in soil Cr levels with respect to …

Fabrication Method For Adhesive Pressure Bonding Two Components Together With Closed-Loop Control, Gary B. Hughes, James P. Mcdonald, Arthur V. Schweidler, Lloyd D. Ingle

Statistics

Two components are bonded together in a bonding apparatus using a bonding medium of malleable metallic spheres and a curable adhesive. The two components are bonded by positioning the components in a facing-but-spaced-apart relation in the bonding apparatus with the spheres and the adhesive between the first component and the second component. The bonding apparatus forces the first component toward the second component with sufficient force to bond the spheres to the first component and to the second component, while monitoring at least one measured bonding reaction of the first component and the second component, and controlling the bonding apparatus …

Photon And Neutral Pion Production In Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez

Physics

We report inclusive photon measurements about midrapidity (∣y∣<0.5) from ¹⁹⁷Au+¹⁹⁷Au collisions at √s_NN=130 GeV at RHIC. Photon pair conversions were reconstructed from electron and positron tracks measured with the Time Projection Chamber (TPC) of the STAR experiment. With this method, an energy resolution of ΔE ∕ E≈2% at 0.5GeV has been achieved. Reconstructed photons have also been used to measure the transverse momentum (p_t) spectra of π0mesons about midrapidity (∣y∣<1) via the π⁰→γγ decay channel. The fractional contribution of the π⁰→γγ decay to the inclusive photon spectrum decreases by 20%±5% between p_{t …}

Rapidity And Centrality Dependence Of Proton And Antiproton Production From 197Au + 197Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez

Physics

We report on the rapidity and centrality dependence of proton and antiproton transverse mass distributions from ¹⁹⁷Au+¹⁹⁷Au collisions at √s_NN=130 GeV as measured by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). Our results are from the rapidity and transverse momentum range of ∣y∣<0.5 and 0.35 < p_t < 1.00 GeV ∕ c. For both protons and antiprotons, transverse mass distributions become more convex from peripheral to central collisions demonstrating characteristics of collective expansion. The measured rapidity distributions and the mean transverse momenta versus rapidity are flat within ∣y∣<0.5. Comparisons of our data with results from model calculations indicate that in order to obtain a consistent picture of the proton (antiproton) yields and transverse mass distributions the possibility of prehadronic collective expansion may have to be taken into account.

Centrality And Pseudorapidity Dependence Of Charged Hadron Production At Intermediate PT In Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez

Physics

We present STAR measurements of charged hadron production as a function of centrality in Au+Au collisions at √s_NN=130 GeV. The measurements cover a phase space region of 0.2T<6.0GeV∕c in transverse momentum and −1<η<1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5<∣η∣<1 are reported and compared to our previously published results for ∣η∣<0.5. No significant difference is seen for inclusive p_T distributions of charged hadrons in these two pseudorapidity bins. We measured dN∕dη distributions and truncated mean p_T in a region of p_T>p_T^cut, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured p_T region. The relative importance of hard scattering processes is investigated through binary …

Mechanisms Of Lead, Copper, And Zinc Retention By Phosphate Rock, Xinde Cao, Lena Q. Ma, Dean R. Rhue, Chip S. Appel

Earth and Soil Sciences

The solid–liquid interface reaction between phosphate rock (PR) and metals (Pb, Cu, and Zn) was studied. Phosphate rock has the highest affinity for Pb, followed by Cu and Zn, with sorption capacities of 138, 114, and 83.2 mmol/kg PR, respectively. In the Pb–Cu–Zn ternary system, competitive metal sorption occurred with sorption capacity reduction of 15.2%, 48.3%, and 75.6% for Pb, Cu, and Zn, respectively compared to the mono-metal systems. A fractional factorial design showed the interfering effect in the order of Pb > Cu > Zn. Desorption of Cu and Zn was sensitive to pH change, increasing with pH decline, whereas Pb …

Sequential Interferometric Techniques For Measuring Independent Values Of The Refractive Index And Material Thickness Of Semiconductor Wafers, Glen D. Gillen, Shekhar Guha

Physics

A technique is presented using both Michelson and Fabry-Perot interferometry to independently measure the refractive index and the material thickness of semiconductor wafers. The method does not require accurate prior knowledge of either quantity.

Spatiotemporal Distribution Of Marine Magnetotactic Bacteria In A Seasonally Stratified Coastal Salt Pond, S. L. Simmons, S. M. Sievert, Richard B. Frankel, Dennis A. Bazylinski, K. J. Edwards

Physics

The occurrence and distribution of magnetotactic bacteria (MB) were studied as a function of the physical and chemical conditions in meromictic Salt Pond, Falmouth, Mass., throughout summer 2002. Three dominant MB morphotypes were observed to occur within the chemocline. Small microaerophilic magnetite-producing cocci were present at the top of the chemocline, while a greigite-producing packet-forming bacterium occurred at the base of the chemocline. The distributions of these groups displayed sharp changes in abundance over small length scales within the water column as well as strong seasonal fluctuations in population abundance. We identified a novel, greigite-producing rod in the sulfidic hypolimnion …

Production Of E+E− Pairs Accompanied By Nuclear Dissociation In Ultraperipheral Heavy-Ion Collisions, Star Collaboration, T.D. Gutierrez

Physics

We present data on e⁺e⁻ pair production accompanied by nuclear breakup in ultraperipheral gold-gold collisions at a center of mass energy of 200GeV per nucleon pair. The nuclear breakup requirement selects events at small impact parameters, where higher-order diagrams for pair production should be enhanced. We compare the data with two calculations: one based on the equivalent photon approximation, and the other using lowest-order quantum electrodynamics (QED). The data distributions agree with both calculations, except that the pair transverse momentum spectrum disagrees with the equivalent photon approach. We set limits on higher-order contributions to the cross section.

Proceedings Of The 2004 Onr Decision-Support Workshop Series: Interoperability, Collaborative Agent Design Research Center

Collaborative Agent Design (CAD) Research Center

In August of 1998 the Collaborative Agent Design Research Center (CADRC) of the California Polytechnic State University in San Luis Obispo (Cal Poly), approached Dr. Phillip Abraham of the Office of Naval Research (ONR) with the proposal for an annual workshop focusing on emerging concepts in decision-support systems for military applications. The proposal was considered timely by the ONR Logistics Program Office for at least two reasons. First, rapid advances in information systems technology over the past decade had produced distributed collaborative computer-assistance capabilities with profound potential for providing meaningful support to military decision makers. Indeed, some systems based on …

Interoperability And The Need For Intelligent Software: A Historical Perspective, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

With the objective of defining the interoperability theme of this year’s conference it is the purpose of this paper¹ to trace the evolution of intelligent software from data-centric applications that essentially encapsulate their data environment to ontology-based applications with automated reasoning capabilities. The author draws a distinction between human intelligence and component capabilities within a more general definition of intelligence; - a kind of intelligence that can be embedded in computer software. The primary vehicle in the quest for intelligent software has been the gradual recognition of the central role played by data and information, rather than the logic …

Utilizing Learning Styles For Interactive Tutorials, Magnus Aase, Franz J. Kurfess

Computer Science and Software Engineering

Developing successful Web-based learning environments has shown to be a challenging and difficult endeavor [7][11] that requires knowledge from multiple domains like pedagogy, psychology, knowledge engineering, software engineering, and Web technologies. Their lack of individual preferred ways of instruction is a challenge we address in this paper. We introduce a Web-based learning environment that teaches concepts from Artificial Intelligence to college students. This environment is intended to be used as a complementary tool for the standard lectures. By adapting the instruction and learning material to the individual student’s learning style the tutorial gives the student a personal learning experience and …

Databases For Interval Probabilities, Wenzhong Zhao, Alex Dekhtyar, Judy Goldsmith

Computer Science and Software Engineering

We present a database framework for the efficient storage and manipulation of interval probability distributions and their associated information. Although work on interval probabilities and on probabilistic databases has appeared before, ours is the first to combine these into a coherent and mathematically sound framework including both standard relational queries and queries based on probability theory. In particular, our query algebra allows users not only to query existing interval probability distributions, but also to construct new ones by means of conditionalization and marginalization, as well as other more common database operations.

Helping Analysts Trace Requirements: An Objective Look, Jane Huffman Hayes, Alex Dekhtyar, Senthil Karthikeyan Sundaram, Sarah Howard

Computer Science and Software Engineering

This paper addresses the issues related to improving the overall quality of the requirements tracing process for Independent Verification and Validation analysts. The contribution of the paper is three-fold: we define requirements for a tracing tool based on analyst responsibilities in the tracing process; we introduce several new measures for validating that the requirements have been satisfied; and we present a prototype tool that we built, RETRO (REquirements TRacing On-target), to address these requirements. We also present the results of a study used to assess RETRO’s support of requirements and requirement elements that can be measured objectively.

Possible Worlds Semantics For Probabilistic Logic Programs, Alex Dekhtyar, Michael I. Dekhtyar

Computer Science and Software Engineering

In this paper we consider a logic programming framework for rea-soning about imprecise probabilities. In particular, we propose a new semantics, for the Probabilistic Logic Programs (p-programs) of Ng and Subrahmanian. P-programs represent imprecision using probability intervals. Our semantics, based on the possible worlds semantics, considers all point probability distributions that satisfy a given p-program. In the paper, we provide the exact characterization of such models of a p-program. We show that the set of models of a p-program can-not, in general case, be described by single intervals associated with atoms of the program. We provide algorithms for efficient construction …

Modeling And Propagation Of Near-Field Diffraction Patterns: A More Complete Approach, Glen D. Gillen, Shekhar Guha

Physics

We discuss the origins and regions of validity of various near-field diffraction models. The complete Rayleigh–Sommerfeld model is found to accurately represent intensity distributions for axial distances up to and including the location of the aperture, a region where commonly used models fail. We show that near-field diffraction theory can be applied to the refraction of light at an interface between two different media yielding results that demonstrate the validity of Snell’s law in the presence of diffraction. Calculations using near-field diffraction and Fourier optics are compared to experimentally measured intensity distributions

Enhancement Of Curie Temperature In Ga1−XMnXAs Epilayers Grown On Cross-Hatched InYGa1−YAs Buffer Layers, O. Maksimov, B.L. Sheu, G. Xiang, N. Keim, P. Schiffer, N. Samarth

Physics

Relaxed In_yGa_1−yAs epilayers grown on (0 0 1) GaAs are known to exhibit a cross-hatched surface with ridges running along the [1 1 0] and directions. We find that Ga_1−xMn_xAs epilayers grown on such buffer layers can have as-grown Curie temperatures (T_C) that are higher than the as-grown 110 K value typical of Ga_1−xMn_xAs/GaAs heterostructures. Further, low-temperature annealing leads to only modest additional increases in T_C, contrasting with the behavior in Ga_1−xMn_xAs/GaAs where T_{C …}

The Tirac™ Development Toolkit: Purpose And Overview, Jens G. Pohl, Kym Jason Pohl, Russell Leighton, Michael Zang, Steven Gollery, Mark Porczak

Collaborative Agent Design (CAD) Research Center

This report provides an overview description of the Toolkit for Information Representation and Agent Collaboration (TIRAC™) software framework for the development of intelligent decision-support applications. More technical descriptions of TIRAC™ are contained in a companion CDM Technical Report (CDM-19-03) entitled: ‘The TIRAC™ Development Toolkit: Technical Description’.

TIRAC™ is an application development framework and toolkit for decision-support systems incorporating software agents that collaborate with each other and human users to monitor changes (i.e., events) in the state of problem situations, generate and evaluate alternative plans, and alert human users to immediate and developing resource shortages, failures, threats, and similar adverse conditions. …

Examination Of Technologies For Student-Generated Work In A Peer-Led, Peer-Review Instructional Environment, Brian P. Coppola, Alan L. Kiste

Chemistry and Biochemistry

There is a growing literature demonstrating the effectiveness of using computer environments to assist students’ in visualizing science and mathematics concepts. However, with many of these computerized learning environments, students do not have the option of manipulating the environment. Instead, they are presented with pre-made visualizations. Enabling students to display their understanding through multiple representational forms is more interesting. In our peer-led, peer-review environment, students generate a complex, literature-based, multimedia text on which their final examination is based. However, there are great time and personnel costs in this design. Collaborating with SRI Inc., we are addressing these demands via the …

Pre-Conference Proceedings Of The Focus Symposium On Intelligent Software Systems For The New Infostructure: Baden-Baden, Germany, Collaborative Agent Design Research Center

Collaborative Agent Design (CAD) Research Center

Over the past several years the papers in this annual series of symposia have increasingly centered on the realization of a human-computer collaboration environment in which computer-based software agents with reasoning capabilities provide meaningful support to human decision makers. It is therefore quite appropriate that the first paper in the 2004 Proceedings should address the historical evolutionary path of ‘intelligent’ software leading to the goal of a semantic Web environment. The realization of this goal is now in sight, driven by public security threats that are increasingly relying on technology for effective countermeasures.

The Evolution Of Intelligent Computer Software And The Semantic Web, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

The purpose of this paper is to trace the evolution of intelligent software from data-centric applications that essentially encapsulate their data environment to ontology-based applications with automated reasoning capabilities. The author draws a distinction between human intelligence and component capabilities within a more general definition of intelligence, which may be embedded in computer software. The primary vehicle in the quest for intelligent software has been the gradual recognition of the central role played by data and information, rather than the logic and functionality of the application. The three milestones in this evolution have been: the separation of data management from …

Mean-Field Theory Of Collective Transport With Phase Slips, Karl Saunders, J. M. Schwarz, M. Christina Marchetti, A. Alan Middleton

Physics

The driven transport of plastic systems in various disordered backgrounds is studied within mean field theory. Plasticity is modeled using nonconvex interparticle potentials that allow for phase slips. This theory most naturally describes sliding charge density waves; other applications include flow of colloidal particles or driven magnetic flux vortices in disordered backgrounds. The phase diagrams exhibit generic phases and phase boundaries, though the shapes of the phase boundaries depend on the shape of the disorder potential. The phases are distinguished by their velocity and coherence: the moving phase generically has finite coherence, while pinned states can be coherent or incoherent. …

Fire Regimes And Resultant Forest Structure In Native Año Nuevo Monterey Pine (Pinus Radiata) Forest, California, Scott L. Stephens, Douglas D. Piirto, Domenico F. Caramagno

Natural Resources Management and Environmental Sciences

Native Monterey pine (Pinus radiata) forests occur in five populations on the west coast of North America. High severity fire has been reported to be the main disturbance agent that initiates seedling establishment for this species. To investigate the impacts of fire in this ecosystem, age structure and fire history data were collected from the native Ano Nuevo Monterey pine forest near Santa Cruz California. Stump cross-sections were removed from 10 randomly placed openings, and each was dated to determine tree age and fire history. Average mean fire return intervals were 11.2-20.1 y. Fifty-one percent of the Monterey …

National Academy Of Sciences Study On The Comprehensive Nuclear Test Ban Treaty, David W. Hafemeister

Physics

No abstract provided.

Knowledge Management Using Semantic Web Languages And Technologies, Steven J. Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Each organization of more than a few persons generates a number of documents containing information about the activities of the organization. The sum of these documents provides a kind of organizational memory that can be used both in evaluations of past performance and as the basis of future planning based on previous experience.

Unfortunately, the nature of these documents mitigates against the reuse of information for purposes other than those for which each document was originally intended. To locate all the information about some aspect of the organization, it frequently becomes necessary for human beings to search a mass of …

Azimuthally Sensitive Hanbury Brown–Twiss Interferometry In Au+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez

Physics

We present the results of a systematic study of the shape of the pion distribution in coordinate space at freeze-out in Au+Au collisions at BNL RHIC using two-pion Hanbury Brown–Twiss (HBT) interferometry. Oscillations of the extracted HBT radii versus emission angle indicate sources elongated perpendicular to the reaction plane. The results indicate that the pressure and expansion time of the collision system are not sufficient to completely quench its initial shape.

Intensity Interferometry With Anyons, Thomas D. Gutierrez

Physics

A pairwise correlation function in relative momentum space is discussed as a tool to characterize the properties of an incoherent source of noninteracting Abelian anyons. This is analogous to the Hanbury-Brown Twiss effect for particles with fractional statistics in two dimensions. In particular, using a flux tube model for anyons, the effects of source shape and quantum statistics on a two-particle correlation function are examined. Such a tool may prove useful in the context of quantum computing and other experimental applications where studying anyon sources are of interest.

Content-Based Framework For Component Libraries, Franz J. Kurfess, Ching Kang Cheng, Z. Y. Wang, L. Jololian

Computer Science and Software Engineering

The construction of large software systems from existing components requires efficient access to possibly large collections of such components. In this paper, we present a content-based framework to organize this large collection of components in a semi-automatic fashion, according to an extensible user-defined ontology. Neural associative memories are used for fast, similarity-based access. Relevant characteristics of components are extracted and stored as a ``signature'' in such an associative memory, and during retrieval the closest matches to the query are indicated in very short time. In addition to content-based characteristics such as keywords, function and variable names, comments, and the location …

A Novel Distributed Denial-Of-Service Detection Algorithm, Brett Tsudama

Master's Theses

The applicability of implementing Ratio-based SYN Flood Detection (RSD) on a network processor is explored, and initial results are presented.

Multistrange Baryon Production In Au-Au Collisions At √ SNn = 130 Gev, Star Collaboration, T.D. Gutierrez

Physics

The transverse mass spectra and midrapidity yields for Ξs and Ωs are presented. For the 10% most central collisions, the ¯Ξ¯+/h− ratio increases from the Super Proton Synchrotron to the Relativistic Heavy Ion Collider energies while the Ξ−/h⁻stays approximately constant. A hydrodynamically inspired model fit to the Ξ spectra, which assumes a thermalized source, seems to indicate that these multistrange particles experience a significant transverse flow effect, but are emitted when the system is hotter and the flow is smaller than values obtained from a combined fit to π, K, p, and Λs.