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PADRE: a parallel asynchronous data routing environment

Description: Increasingly in industry, software design and implementation is object-oriented, developed in C++ or Java, and relies heavily on pre-existing software libraries (e.g. the Microsoft Foundation Classes for C++, the Java API for Java). A similar but more tentative trend is developing in high-performance parallel scientific computing. The transition from serial to parallel application development considerably increases the need for library support: task creation and management, data distribution an… more
Date: January 8, 2001
Creator: Gunney, B & Quinlan, D
Partner: UNT Libraries Government Documents Department
open access

Asymptotic technique for the far field pattern of a dipole in an infinite stratified medium

Description: Modern antennas especially arrays are being placed in layers of materials on complex environments. This technique produces aesthetically pleasing structures if necessary, allows for more freedom in structure planning, and can improve antenna performance. In the past, buried antennas have been studied by numerous authors such as in Reference. Recent work on this subject uses spectral and/or numerical moment method formulations. For high frequency analysis it is important to find efficient and ac… more
Date: January 8, 2001
Creator: Rockway, J T; Marhefka, R J & Champagne, N
Partner: UNT Libraries Government Documents Department
open access

ErbB2, but not ErbB1, reinitiates proliferation and induces luminal repopulation in epithelial acini

Description: Both ErbB1 and ErbB2 are overexpressed or amplified in breast tumors. To examine the effects of activating ErbB receptors in a context that mimics polarized epithelial cells in vivo, we activated ErbB1 and ErbB2 homodimers in preformed, growth-arrested mammary acini cultured in three-dimensional basement membrane gels. Activation of ErbB2, but not that of ErbB1, led to a reinitiation of cell proliferation and altered the properties of mammary acinar structures. These altered structures share se… more
Date: August 8, 2001
Creator: Muthuswamy, Senthil K; Li, Dongmei; Lelievre, Sophie; Bissell, Mina J & Brugge, Joan S
Partner: UNT Libraries Government Documents Department
open access

Complete mtDNA sequences of two millipedes suggest a new model for mitochondrial gene rearrangements: Duplication and non-random loss

Description: We determined the complete mtDNA sequences of the millipedes Narceus annularus and Thyropygus sp. (Arthropoda: Diplopoda) and identified in both genomes all 37 genes typical for metazoan mtDNA. The arrangement of these genes is identical in the two millipedes, but differs from that inferred to be ancestral for arthropods by the location of four genes/gene clusters. This novel gene arrangement is unusual for animal mtDNA, in that genes with opposite transcriptional polarities are clustered in th… more
Date: November 8, 2001
Creator: Lavrov, Dennis V.; Boore, Jeffrey L. & Brown, Wesley M.
Partner: UNT Libraries Government Documents Department
open access

New limit on the electron electric dipole moment

Description: We present the result of our most recent search for T-violation in 205Tl, which is interpreted in terms of an electric dipole moment of the electron de. We find de = (6.9 plus/minus 7.4) times 10{sup -28} e cm. The present apparatus is a major upgrade of the atomic beam magnetic resonance device used to set the previous limit on de.
Date: August 8, 2001
Creator: Regan, B.C.; Commins, Eugene D.; Schmidt, Christian J. & DeMille, David
Partner: UNT Libraries Government Documents Department
open access

Analysis and testing of rupture of steam generator tubing with flaws.

Description: A high-temperature (300 C), high-pressure (18 MPa), and high-leak rate (1500 L/min) facility, and a room temperature, high-pressure (52 MPa) test facility were used to test flawed steam generator tubes. Single and multiple rectangular flaws were fabricated by electro-discharge machining on the outside surface of the tubes. This paper briefly reviews analytical methods for predicting ligament rupture and unstable burst of tubes with single and multiple rectangular flaws. Test data are presented … more
Date: February 8, 2001
Creator: Majumdar, S.; Kasza, K. S.; Park, J. Y. & Hanna, J. A.
Partner: UNT Libraries Government Documents Department
open access

RHIC EXPERIMENTAL RESULTS.

Description: A summary of measurements from the first year's run at RHIC is presented. The second year's run at RHIC is presently underway with Au+Au (300 {micro}b{sup -1}) and p-p (3.5 pb{sup -1}) collisions planned at {radical}s{sub NN} = 200 GeV.
Date: June 8, 2001
Creator: TANNENBAUM,M.J.
Partner: UNT Libraries Government Documents Department
open access

Adaptive path planning algorithm for cooperating unmanned air vehicles

Description: An adaptive path planning algorithm is presented for cooperating Unmanned Air Vehicles (UAVs) that are used to deploy and operate land-based sensor networks. The algorithm employs a global cost function to generate paths for the UAVs, and adapts the paths to exceptions that might occur. Examples are provided of the paths and adaptation.
Date: February 8, 2001
Creator: Cunningham, C T & Roberts, R S
Partner: UNT Libraries Government Documents Department
open access

Axions from wall decay

Description: The authors discuss the decay of axion walls bounded by strings and present numerical simulations of the decay process. In these simulations, the decay happens immediately, in a time scale of order the light travel time, and the average energy of the radiated axions is <w{sub a}> {approx_equal} 7m{sub a} for v{sub a}/m{sub a} {approx_equal} 500. <w{sub a}> is found to increase approximately linearly with ln(v{sub a}/m{sub a}). Extrapolation of this behavior yields <w{sub a}> {… more
Date: January 8, 2001
Creator: Chang, S.; Hagmann, C. & Sikivie, P.
Partner: UNT Libraries Government Documents Department
open access

AMRSim: an object-oriented performance simulator for parallel adaptive mesh refinement

Description: Adaptive mesh refinement is complicated by both the algorithms and the dynamic nature of the computations. In parallel the complexity of getting good performance is dependent upon the architecture and the application. Most attempts to address the complexity of AMR have lead to the development of library solutions, most have developed object-oriented libraries or frameworks. All attempts to date have made numerous and sometimes conflicting assumptions which make the evaluation of performance of … more
Date: January 8, 2001
Creator: Miller, B; Philip, B; Quinlan, D & Wissink, A
Partner: UNT Libraries Government Documents Department
open access

Evaluation of the Impact of CO2, Aqueous Fluid, and Reservoir Rock Interactions on the Geologic Sequestration of CO2 with Special Emphasis on Economic Implications

Description: Lowering the costs of front-end processes in the geologic sequestration of CO{sub 2} can dramatically lower the overall costs. One approach is to sequester less-pure CO{sub 2} waste streams that are less expensive or require less energy to separate from flue gas, a coal gasification process, etc. The objective of this research is to evaluate the impacts of an impure CO{sub 2} waste stream on geologic sequestration using both reaction progress and reactive transport simulators. The simulators se… more
Date: March 8, 2001
Creator: Knauss, K. G.; Johnson, J. W.; Steefel, C. I. & Nitao, J. J.
Partner: UNT Libraries Government Documents Department
open access

Implementation of Deterministically-Derived Hydrostatigraphic Units into a 3D Finite Element Model at the Lawrence Livermore Laboratory Superfund Site

Description: Lawrence Livermore National Laboratory (LLNL) is a large Superfund site in California that is implementing an extensive ground water remediation program. The site is underlain by a thick sequence of heterogeneous alluvial sediments. Defining ground-water flow pathways in this complex geologic setting is difficult. To better evaluate these pathways, a deterministic approach was applied to define hydrostratigraphic units (HSUS) on the basis of identifiable hydraulic behavior and contaminant migra… more
Date: August 8, 2001
Creator: Mansoor, K; Maley, M; Demir, Z & Hoffman, F
Partner: UNT Libraries Government Documents Department
open access

ROSETTA: the compile-time recognition of object-oriented library abstractions and their use within user applications

Description: Libraries arise naturally from the increasing complexity of developing scientific applications, the optimization of libraries is just one type of high-performance optimization. Many complex applications areas can today be addressed by domain-specific object-oriented frameworks. Such object-oriented frameworks provide an effective compliment to an object-oriented language and effectively permit the design of what amount to essentially domain-specific languages. The optimization of such a domain-… more
Date: January 8, 2001
Creator: Quinlan, D & Philip, B
Partner: UNT Libraries Government Documents Department
open access

Detonation Product EOS Studies: Using ISLS to Refine Cheetah

Description: Knowledge of an effective interatomic potential function underlies any effort to predict or rationalize the properties of solids and liquids. The experiments we undertake are directed towards determination of equilibrium and dynamic properties of simple fluids at densities sufficiently high that traditional computational methods and semi-empirical forms successful at ambient conditions may require reconsideration. In this paper we present high-pressure and temperature experimental sound speed d… more
Date: August 8, 2001
Creator: Zaug, J M; Howard, W M; Fried, L E & Hansen, D W
Partner: UNT Libraries Government Documents Department
open access

MPX: software for multiplexing hardware performance counters in multithreaded programs

Description: Hardware performance counters are CPU registers that count data loads and stores, cache misses, and other events. Counter data can help programmers understand software performance. Although CPUs typically have multiple counters, each can monitor only one type of event at a time, and some counters can monitor only certain events. Therefore, some CPUs cannot concurrently monitor interesting combinations of events. Software multiplexing partly overcomes this limitation by using time sharing to mon… more
Date: January 8, 2001
Creator: May, J M
Partner: UNT Libraries Government Documents Department
open access

Radiation Driven Capsules for Fast Ignition

Description: The energy required to ignite compressed deuterium-tritium fuel is a strong function of the fuel density. Through a series of detailed numerical simulations, peak fuel densities have been calculated as a function of the peak radiation drive temperature. Note that the time dependence of the radiation temperature (pulse shaping) has been optimized to obtain maximum density for each scaling point. A simple analytic scaling is developed, which agrees well with the numerical results. These scaling r… more
Date: June 8, 2001
Creator: Herrmann, M & Slutz, S A
Partner: UNT Libraries Government Documents Department
open access

The liquid to vapor phase transition in excited nuclei

Description: For many years it has been speculated that excited nuclei would undergo a liquid to vapor phase transition. For even longer, it has been known that clusterization in a vapor carries direct information on the liquid-vapor equilibrium according to Fisher's droplet model. Now the thermal component of the 8 GeV/c pion + 197 Au multifragmentation data of the ISiS Collaboration is shown to follow the scaling predicted by Fisher's model, thus providing the strongest evidence yet of the liquid to vapor… more
Date: May 8, 2001
Creator: Elliott, J. B.; Moretto, L. G.; Phair, L.; Wozniak, G. J.; Beaulieu, L.; Breuer, H. et al.
Partner: UNT Libraries Government Documents Department
open access

WUFI-ORNL/IBP Hygrothermal Model

Description: Moisture engineering is becoming an important task in the overall design of building enclosures in both North America and Europe. Several methods may be used to design wall systems, and modeling is definitively the most flexible approach. There is an increasing demand for calculation methods to assess the moisture behavior of building components. In North America alone, the estimated cost in increased energy consumption due to the presence of moisture is approximately $1 billion dollars annuall… more
Date: August 8, 2001
Creator: Karagiozis, A.N.
Partner: UNT Libraries Government Documents Department
open access

Synthesis of a New Family of Fluorinated Boronate Compounds as Anion Receptors and Studies of Their Use as Additives in Lithium Battery Electrolytes.

Description: Numerous studies have been done on developing new electrolytes for lithium batteries with high ionic conductivity, and good chemical and electrochemical stability. In addition to the research on new salts and solvents, the use of cation receptors to reduce ion pairing in non-aqueous electrolytes has been considered as an approach to improve the properties of electrolytes. Although both cation and anion receptors enhance the dissociation of ion pairs and increase the conductivity of electrolytes… more
Date: June 8, 2001
Creator: Mcbreen, J.; Lee, H. S. & Yang, X. Q.
Partner: UNT Libraries Government Documents Department
open access

Dual-Fiberoptic Microcantilever Proximity Sensor

Description: Microcantilevers are key components of many Micro-Electro-Mechanical Systems (MEMS) and Micro-Optical-Electro-Mechanical Systems (MOEMS) because slight changes to them physically or chemically lead to changes in mechanical characteristics. An inexpensive dual-fiberoptic microcantilever proximity sensor and model to predict its performance are reported here. Motion of a magnetic-material-coated cantilever is the basis of a system under development for measuring magnetic fields. The dual fiber pr… more
Date: August 8, 2001
Creator: Goedeke, S.M.
Partner: UNT Libraries Government Documents Department
open access

Thermoelastic response of suddenly heated liquid targets in high-power colliders.

Description: Thermoelastic response of liquid metal targets exposed to high-volumetric-energy deposition in times shorter than the target hydrodynamic response time (i.e., sound travel time) is of interest to several research areas, including targets for high-power accelerators such as the Spallation Neutron Source, muon collider targets, etc. Sudden energy deposition causes shock and rarefaction waves of magnitude {+-} {Delta}P that corresponds to an initial thermal pressure of tens of katm. Nevertheless a… more
Date: August 8, 2001
Creator: Hassanein, A.; Konkashbaev, I. & Norem, J.
Partner: UNT Libraries Government Documents Department
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