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Advances in the theory of box integrals

Description: Box integrals - expectations <|{rvec r}|{sup s}> or <|{rvec r}-{rvec q}|{sup s}> over the unit n-cube (or n-box) - have over three decades been occasionally given closed forms for isolated n,s. By employing experimental mathematics together with a new, global analytic strategy, we prove that for n {le} 4 dimensions the box integrals are for any integer s hypergeometrically closed in a sense we clarify herein. For n = 5 dimensions, we show that a single unresolved integral we call K{sub 5} stands in the way of such hyperclosure proofs. We supply a compendium of exemplary closed forms that naturally arise algorithmically from this theory.
Date: June 25, 2009
Creator: Bailey, David H.; Borwein, J.M. & Crandall, R.E.
Partner: UNT Libraries Government Documents Department

Hydrologic Effects of Annually Diverting 131,000 Acre-Feet of Water from Dillon Reservoir, Central Colorado

Description: From abstract: because of the increased demands for water in eastern Colorado, principally in the urbanizing Denver metropolitan area, increased diversions of water from Dillon Reservoir are planned. Estimates of end-of-month storage in Dillon Reservoir, assuming the reservoir was in place and 131,000 acre-feet of water were diverted from the reservoir each year, were reconstructed by mass balance for the 1931-77 water years. Based on the analysis, the annual maximum end-of-month drawdown below the elevation at full storage would have been 171 feet.
Date: January 1979
Creator: Alley, W. M.; Bauer, D. P.; Veenhuis, J. E. & Brennan, Robert
Partner: UNT Libraries Government Documents Department

Development of a RAMI Program for LANSCE upgrade

Description: Improvement of beam availability is a prime objective of the present LANSCE (Los Alamos Neutron Scattering Center) Upgrade. A RAMI (reliability, availability, maintainability, and inspectability) program is being developed to identify the most cost-effective improvements to achieve the availability goal. The beam-delivery system is divided into subsystems appropriate for the modeling of availability. The availability of each subsystem is determined from operation data and assessment of individual component designs. These availability data are incorporated in an availability model to predict the benefit of improvement projects to achieve cost-benefit prioritization. Examination of the data also identifies a comprehensive list of factors affecting availability. A good understanding of these factors using root-cause analysis is essential for availability improvement. This paper describes the RAMI program and the development of the availability model.
Date: May 1, 1995
Creator: Chan, K.C.D.; Hutson, R.L.; Macek, R.J.; Tallerico, P.J. & Wilkinson, C.A.
Partner: UNT Libraries Government Documents Department

Testing of the TriP Chip Running at 132 nsec Using a Modified AFE Board

Description: In this note we describe the first set of tests done with a sample of TriP chips that were mounted on a modified AFE board. The modifications consisted of different firmware and the replacement of one power supply switch. The board used was a standard AFEIc board (red type) on which new MCMs (MCMIIs) were mounted. The new MCMs were designed to support the TriP and emulate the SVX for readout when mounted on an AFEIc board. The TriP and the MCMs are described in Ref. [1]. Two versions of the MCMII were designed and built: one (MCMIIb) supports two TriP chips wirebonded directly to the MCM substrate. The other, (MCMIIc) supports one TriP which can be either wirebonded directly or packaged into a standard TQFP surface mount package. Due to space constraints, this MCM can support only 1 TriP. We tested 6 TriP chips on 3 different MCMIIb (MCMIIb-1, MCMIIb-2 and MCMIIb-3) and 2 other TriPs were tested on MCMIIc, one of them with an unpackaged TriP (MCMIIc-1) and the other with a packaged TriP (MCMIIc-2). A set of 10 programable internal registers control the TriP operation, the description of these registers can be found in [1]. Table 1 shows the values used for the tests described in this note. In Ref. [1] there is a description of the signals that are needed to operate the TriP chip. We implemented in a Field Programable Gate Array (FPGA), also part of the MCM, a set of shift registers that allow us to download via the 1553 interface to the AFE board, any desired timing for the signals that the FPGA has to send to the TriP chip. These registers are run with a 121.21 MHz clock (which is 16x the crossing clock and phase locked to it), which means that ...
Date: December 19, 2003
Creator: al., Juan Estrada et
Partner: UNT Libraries Government Documents Department

Bioavailability: implications for science/cleanup policy

Description: This paper examines the role of bioavailability in risk assessment and cleanup decisions. Bioavailability refers to how chemicals ''behave'' and their ''availability'' to interact with living organisms. Bioavailability has significant implications for exposure risks, cleanup goals, and site costs. Risk to human health and the environment is directly tied to the bioavailability of the chemicals of concern.
Date: December 1, 1998
Creator: Denit, Jeffery & Planicka, J. Gregory
Partner: UNT Libraries Government Documents Department

A study of defects on EUV mask using blank inspection, patterned mask inspection, and wafer inspection

Description: The availability of defect-free masks remains one of the key challenges for inserting extreme ultraviolet lithography (EUVL) into high volume manufacturing. yet link data is available for understanding native defects on real masks. In this paper, a full-field EUV mask is fabricated to investigate the printability of various defects on the mask. The printability of defects and identification of their source from mask fabrication to handling were studied using wafer inspection. The printable blank defect density excluding particles and patterns is 0.63 cm{sup 2}. Mask inspection is shown to have better sensitivity than wafer inspection. The sensitivity of wafer inspection must be improved using through-focus analysis and a different wafer stack.
Date: March 12, 2010
Creator: Huh, S.; Ren, L.; Chan, D.; Wurm, S.; Goldberg, K. A.; Mochi, I. et al.
Partner: UNT Libraries Government Documents Department

Hydrogen separation membranes - annual report for FY 2007.

Description: The objective of this work is to develop dense ceramic membranes for separating hydrogen from other gaseous components in a nongalvanic mode, i.e., without using an external power supply or electrical circuitry.
Date: January 31, 2008
Creator: Chen, L.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Park, C. Y.; Picciolo, J. J. et al.
Partner: UNT Libraries Government Documents Department

Eastern Seaboard Electric Grid Fragility Maps Supporting Persistent Availability

Description: Persistently available power transmission can be disrupted by weather causing power outages with economic and social consequences. This research investigated the effects on the national power grid from a specific weather event, Hurricane Irene, that caused approximately 5.7 million customer power outages along the Eastern Seaboard in August of 2011. The objective was to describe the geographic differences in the grid s vulnerability to these events. Individual factors, such as wind speed or precipitation, were correlated with the number of outages to determine the greatest mechanism of power failure in hopes of strengthening the future power grid. The resulting fragility maps not only depicted 18 counties that were less robust than the design-standard robustness model and three counties that were more robust, but also drew new damage contours with correlated wind speeds and county features.
Date: November 1, 2012
Creator: Walker, Kimberly A; Weigand, Gilbert G & Fernandez, Steven J
Partner: UNT Libraries Government Documents Department

Removal of Lattice Imperfections that Impact the Optical Quality of Ti:Sapphire using Advanced Magnetorheological Finishing Techniques

Description: Advanced magnetorheological finishing (MRF) techniques have been applied to Ti:sapphire crystals to compensate for sub-millimeter lattice distortions that occur during the crystal growing process. Precise optical corrections are made by imprinting topographical structure onto the crystal surfaces to cancel out the effects of the lattice distortion in the transmitted wavefront. This novel technique significantly improves the optical quality for crystals of this type and sets the stage for increasing the availability of high-quality large-aperture sapphire and Ti:sapphire optics in critical applications.
Date: February 26, 2008
Creator: Menapace, J A; Schaffers, K I; Bayramian, A J; Davis, P J; Ebbers, C A; Wolfe, J E et al.
Partner: UNT Libraries Government Documents Department

Virtual nuclear weapons

Description: The term virtual nuclear weapons proliferation and arsenals, as opposed to actual weapons and arsenals, has entered in recent years the American lexicon of nuclear strategy, arms control, and nonproliferation. While the term seems to have an intuitive appeal, largely due to its cyberspace imagery, its current use is still vague and loose. The author believes, however, that if the term is clearly delineated, it might offer a promising approach to conceptualizing certain current problems of proliferation. The first use is in a reference to an old problem that has resurfaced recently: the problem of growing availability of weapon-usable nuclear materials in civilian nuclear programs along with materials made `excess` to defense needs by current arms reduction and dismantlement. It is argued that the availability of these vast materials, either by declared nuclear-weapon states or by technologically advanced nonweapon states, makes it possible for those states to rapidly assemble and deploy nuclear weapons. The second use has quite a different set of connotations. It is derived conceptually from the imagery of computer-generated reality. In this use, one thinks of virtual proliferation and arsenals not in terms of the physical hardware required to make the bomb but rather in terms of the knowledge/experience required to design, assemble, and deploy the arsenal. Virtual weapons are a physics reality and cannot be ignored in a world where knowledge, experience, materials, and other requirements to make nuclear weapons are widespread, and where dramatic army reductions and, in some cases, disarmament are realities. These concepts are useful in defining a continuum of virtual capabilities, ranging from those at the low end that derive from general technology diffusion and the existence of nuclear energy programs to those at the high end that involve conscious decisions to develop or maintain militarily significant nuclear-weapon capabilities.
Date: August 1, 1997
Creator: Pilat, J.F.
Partner: UNT Libraries Government Documents Department

MEASURES OF DISTORTION IN POSSIBILISTIC APPROXIMATIONS OF CONSISTENT RANDOM SETS AND INTERVALS

Description: The availability of probability or possibility measures for random set (Dempster-Shafer evidence theoretical) structures are highly desirable. Probabilistic conditions involve disjointness or specificity, while possibilistic conditions involve consonance of the underlying focal elements. Consistency results in possibilistic distributions, but not measures, but then a unique approximation is available. Especially in random interval measurement situations, this condition is common. In this paper we develop some of the mathematical ideas necessary to develop a measure of the distortion introduced by this consonant approximation of a consistent random set.
Date: April 1, 2001
Creator: JOSLYN, C.
Partner: UNT Libraries Government Documents Department

Complexity versus availability for fusion: The potential advantages of inertial fusion energy

Description: Probably the single largest advantage of the inertial route to fusion energy (IFE) is the perception that its power plant embodiments could achieve acceptable capacity factors. This is a result of its relative simplicity, the decoupling of the driver and reactor chamber, and the potential to employ thick liquid walls. We examine these issues in terms of the complexity, reliability, maintainability and, therefore, availability of both magnetic and inertial fusion power plants and compare these factors with corresponding scheduled and unscheduled outage data from present day fission experience. We stress that, given the simple nature of a fission core, the vast majority of unplanned outages in fission plants are due to failures outside the reactor vessel itself Given we must be prepared for similar outages in the analogous plant external to a fusion power core, this puts severe demands on the reliability required of the fusion core itself. We indicate that such requirements can probably be met for IFE plants. We recommend that this advantage be promoted by performing a quantitative reliability and availability study for a representative IFE power plant and suggest that databases are probably adequate for this task.
Date: September 5, 1996
Creator: Perkins, L.J.,
Partner: UNT Libraries Government Documents Department

Jefferson Laboratory: Maintenance overview

Description: Maintenance, repair, and upgrades to the Thomas Jefferson National Accelerator Facility, a DOE laboratory located in Newport News, VA, USA, is based upon a two-week run cycle followed by a one-shift maintenance period. The rationale for this approach will be presented including a brief look at the maintenance funding, support staff, and beam availability. Means for improving the machine will be presented including record keeping of downtime, compilation of data, dissemination of findings, and allocation of resources. Maintenance problems facing Jefferson Lab will be presented.
Date: May 1, 1998
Creator: F.Suhring, Steve
Partner: UNT Libraries Government Documents Department

Active system area networks for data intensive computations. Final report

Description: The goal of the Active System Area Networks (ASAN) project is to develop hardware and software technologies for the implementation of active system area networks (ASANs). The use of the term ''active'' refers to the ability of the network interfaces to perform application-specific as well as system level computations in addition to their traditional role of data transfer. This project adopts the view that the network infrastructure should be an active computational entity capable of supporting certain classes of computations that would otherwise be performed on the host CPUs. The result is a unique network-wide programming model where computations are dynamically placed within the host CPUs or the NIs depending upon the quality of service demands and network/CPU resource availability. The projects seeks to demonstrate that such an approach is a better match for data intensive network-based applications and that the advent of low-cost powerful embedded processors and configurable hardware makes such an approach economically viable and desirable.
Date: April 1, 2002
Partner: UNT Libraries Government Documents Department

[Materials Research Collaborative Access Team] Final Report - DOE Grant No.DEFG0200ER45811

Description: Operations Funding for the Materials Research Collaborative Access Team. In the proposal they presented five specific objectives for the MR-CAT Insertion Device beam line: (1) enable the accomplishment of the best possible science at MR-CAT; (2) facilitate efficient set-up and operations of a variety of complex materials-related experiments; (3) open the beamlines' facilities to scientists and science projects from non-traditional backgrounds and disciplines, respectively; (4) enable efficient 24 hour use of the beamline through interdisciplinary research teams and appropriate operations support; and (5) develop selected operations modes in support of the MR-CAT institutions, DOE collaborators, and general users.
Date: May 2, 2004
Creator: Segre, Carlo
Partner: UNT Libraries Government Documents Department

Job scheduling in a heterogenous grid environment

Description: Computational grids have the potential for solving large-scale scientific problems using heterogeneous and geographically distributed resources. However, a number of major technical hurdles must be overcome before this potential can be realized. One problem that is critical to effective utilization of computational grids is the efficient scheduling of jobs. This work addresses this problem by describing and evaluating a grid scheduling architecture and three job migration algorithms. The architecture is scalable and does not assume control of local site resources. The job migration policies use the availability and performance of computer systems, the network bandwidth available between systems, and the volume of input and output data associated with each job. An extensive performance comparison is presented using real workloads from leading computational centers. The results, based on several key metrics, demonstrate that the performance of our distributed migration algorithms is significantly greater than that of a local scheduling framework and comparable to a non-scalable global scheduling approach.
Date: February 11, 2004
Creator: Oliker, Leonid; Biswas, Rupak; Shan, Hongzhang & Smith, Warren
Partner: UNT Libraries Government Documents Department