A sendmail. cf scheme for a large network (open access)

A sendmail. cf scheme for a large network

Like most large networked sites our users depend heavily on the electronic mail system for both internal and off-site communications. Unfortunately the sendmail.cf file, which is used to control the behavior of the sendmail program, is somewhat cryptic and difficult to decipher for the neophyte. So, on one hand you have a highly visible, frequently used utility, and on the other hand a not-so-easily acquired system administration forte. Here is the sendmail topology of our site, what premises we based it on, and the parts of the sendmail.cf files which support the topology.
Date: August 14, 1991
Creator: Darmohray, T.M.
System: The UNT Digital Library
Inherently safe nuclear-driven internal combustion engines (open access)

Inherently safe nuclear-driven internal combustion engines

A family of nuclear driven engines is described in which nuclear energy released by fissioning of uranium or plutonium in a prompt critical assembly is used to heat a working gas. Engine performance is modeled using a code that calculates hydrodynamics, fission energy production, and neutron transport self-consistently. Results are given demonstrating a large negative temperature coefficient that produces self-shutoff of energy production. Reduced fission product inventory and the self-shutoff provide inherent nuclear safety. It is expected that nuclear engine reactor units could be scaled from 100 MW on up. 7 refs., 3 figs.
Date: June 14, 1991
Creator: Alesso, P.; Chow, Tze-Show; Condit, R.; Heidrich, J.; Pettibone, J. & Streit, R.
System: The UNT Digital Library
Nuclear thermal rocket clustering: 1, A summary of previous work and relevant issues (open access)

Nuclear thermal rocket clustering: 1, A summary of previous work and relevant issues

A general review of the technical merits of nuclear thermal rocket clustering is presented. A summary of previous analyses performed during the Rover program is presented and used to assess clustering in the context of projected Space Exploration Initiative missions. A number of technical issues are discussed including cluster reliability, engine-out operation, neutronic coupling, shutdown core power generation, shutdown reactivity requirements, reactor kinetics, and radiation shielding. 7 refs., 3 figs., 2 tabs.
Date: July 14, 1991
Creator: Buksa, J.J. & Houts, M.G.
System: The UNT Digital Library
Modeling of water spraying of field releases of hydrogen fluoride (open access)

Modeling of water spraying of field releases of hydrogen fluoride

The effectiveness of water sprays to absorb HF releases has been recently demonstrated by extended laboratory and field tests. In this paper computer simulations are presented of the Hawk, Nevada Test Site, series of field tests, along with parametric studies of several cases which have not been studied in the field. The model used in these simulations, HFSPRAY, treats the gas-phase as an Eulerean fluid whereas the spray is described according to the Lagrangian approach by a finite number of drops of varying size and trajectory. HFSPRAY simulates the momentum, mass and energy interactions between a water spray and a turbulent plume of HF in air; it is capable of predicting the flow velocities, temperature, water vapor and HF concentration fields in two-dimensional large-geometries, for spraying in any direction, (i.e., down-flow, inclined-down-flow, up-flow, and co-current horizontal flow). 15 refs., 21 figs.
Date: October 14, 1990
Creator: Fthenakis, V.M. (Brookhaven National Lab., Upton, NY (United States)); Schatz, K.W. (Mobil Research and Development Corp., Princeton, NJ (United States)) & Zakkay, V. (New York Univ., NY (United States). Dept. of Applied Science)
System: The UNT Digital Library
Hawaii Geothermal Project Environmental Impact Statement Scoping Meetings. Volume 8 (open access)

Hawaii Geothermal Project Environmental Impact Statement Scoping Meetings. Volume 8

None
Date: March 14, 1992
Creator: unknown
System: The UNT Digital Library
Hawaii Geothermal Project Environmental Impact Statement Scoping Meetings. Volume 7 (open access)

Hawaii Geothermal Project Environmental Impact Statement Scoping Meetings. Volume 7

None
Date: March 14, 1992
Creator: unknown
System: The UNT Digital Library
Technology transfer from the space exploration initiative (open access)

Technology transfer from the space exploration initiative

Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America's competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.
Date: June 14, 1991
Creator: Buden, D.
System: The UNT Digital Library
Spin observables for nucleon-nucleon elastic scattering at large momentum transfer (open access)

Spin observables for nucleon-nucleon elastic scattering at large momentum transfer

We discuss amplitudes for elastic nucleon-nucleon scattering at high energy. The helicity-conserving amplitudes are modeled using a combination of the quark-interchange and the Landshoff mechanisms of perturbative QCD. The relative normalization of these two sets of amplitudes involves a leading order form factor'' which we determine empirically. Our theoretically motivated amplitudes provide an economical description of a large body of existing data and make nontrivial predictions for spin observables. 8 refs., 4 figs.
Date: August 14, 1990
Creator: Ramsey, G.P. (Loyola Univ., Chicago, IL (USA). Dept. of Physics Argonne National Lab., IL (USA))
System: The UNT Digital Library
HYLIFE-II inertial confinement: Fusion power plant design (open access)

HYLIFE-II inertial confinement: Fusion power plant design

The HYLIFE-2 inertial fusion power plant design study uses a liquid fall, in the form of jets to protect the first structural wall from neutron damage, x rays, and blast to provide a 30-y lifetime. HYLIFE-1 used liquid lithium. HYLIFE 2 avoids the fire hazard of lithium by using a molten salt composed of fluorine, lithium, and beryllium (Li{sub 2}BeF{sub 4}) called Flibe. Access for heavy-ion beams is provided. Calculations for assumed heavy-ion beam performance show a nominal gain of 70 at 5 MJ producing 350 MJ, about 5.2 times less yield than the 1.8 GJ from a driver energy of 4.5 MJ with gain of 400 for HYLIFE-1. The nominal 1 GWe of power can be maintained by increasing the repetition rate by a factor of about 5.2, from 1.5 to 8 Hz. A higher repetition rate requires faster re-establishment of the jets after a shot, which can be accomplished in part by decreasing the jet fall height and increasing the jet flow velocity. Multiple chambers may be required. In addition, although not considered for HYLIFE-1, there is undoubtedly liquid splash that must be forcibly cleared because gravity is too slow, especially at high repetition rates. Splash removal can …
Date: December 14, 1990
Creator: Moir, Ralph W.
System: The UNT Digital Library
Heavy ion beam and reactor chamber interface design (open access)

Heavy ion beam and reactor chamber interface design

The design of the heavy-ion beam and the HYLIFE-II reactor chamber interface must provide final focusing quadruple triplets, neutron shielding, fast shutters, vapor condensation and pumping, thermal insulation, and blast resistant structures. The smallest half angle encompassing all beams striking the target might be {plus minus}14{degrees} for an array of 4 {times} 4 beams or {plus minus}9{degrees} if the four corner beams are eliminated, giving a 12-beam array. The target gain drops considerably from the 0{degree} published values because of this finite angle. The assumed one-sided irradiation reduces the number of bending magnets. A 350-MJ yield might be achieved with a 6-MJ driver (gain of 58) (nominal 1000 MWe net power with a repetition rate of 8 Hz). For either lower repetition rate or lower gain the yield must be increased by increasing the driver energy. The beam ports are protected from radiation by an array of vertical and horizontal, neutronically-thick, liquid jets. 6 refs., 7 figs.
Date: December 14, 1990
Creator: Moir, Ralph W.
System: The UNT Digital Library
Oscillating liquid flow ICF Reactor (open access)

Oscillating liquid flow ICF Reactor

Oscillating liquid flow in a falling molten salt inertial confinement fusion reactor is predicted to rapidly clear driver beam paths of residual liquid droplets. Oscillating flow will also provide adequate neutron and x-ray protection for the reactor structure with a short (2-m) fall distance permitting an 8 Hz repetition rate. A reactor chamber configuration is presented with specific features to clear the entire heavy-ion beam path of splashed molten salt. The structural components, including the structure between beam ports, are shielded. 3 refs., 12 figs.
Date: December 14, 1990
Creator: Petzoldt, R.W.
System: The UNT Digital Library
PHIGS PLUS for scientific graphics (open access)

PHIGS PLUS for scientific graphics

This paper gives a brief overview of the use of computer graphics standards in the scientific community. It particularly details how how PHIGS PLUS meets the needs of users at the Lawrence Livermore National Laboratory. Although standards for computer graphics have improved substantially over the past decade, their acceptance in the scientific community has been slow. As the use and diversity of computers has increased, the scientific graphics libraries have not been able to keep pace with the additional capabilities these new machines offer. Therefore, several organizations have or are now working on converting their scientific libraries to reset upon a portable standard. This paper will address why is transition has been so slow and offer suggestions for future standards work to enhance scientific visualization. This work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.
Date: January 14, 1991
Creator: Crawfis, R.A.
System: The UNT Digital Library
Results from hadron colliders (open access)

Results from hadron colliders

The present status of hadron collider physics is reviewed. The total cross section for {bar p} + p has been measured at 1.8 TeV: {sigma}{sub tot} = 72.1 {plus minus} 3.3 mb. New data confirm the UA2 observation of W/Z {yields} {bar q}q. Precision measurements of M{sub W} by UA2 and CDF give an average value M{sub W} = 80.13 {plus minus} 0.30 GeV/c{sup 2}. When combined with measurements of M{sub Z} from LEP and SLC this number gives sin{sup 2}{theta}{sub W} = 0.227 {plus minus} 0.006, or m{sub top} = 130{sub {minus}60}{sup +40} GeV/c{sup 2} from the EWK radiative correction term {Delta}r. Evidence for hadron colliders as practical sources of b quarks has been strengthened, while searches for t quarks have pushed the mass above M{sub W}: m{sub top} > 89 GeV/c{sup 2} 95% cl (CDF Preliminary). Searches beyond the standard model based on the missing E{sub T} signature have not yet produced any positive results. Future prospects for the discovery of the top quark in the range m{sub top} < 200 GeV/c{sup 2} look promising. 80 refs., 35 figs., 7 tabs.
Date: December 14, 1990
Creator: Pondrom, L.G. (Wisconsin Univ., Madison, WI (USA))
System: The UNT Digital Library
A new approach to chiral fermions on the lattice (open access)

A new approach to chiral fermions on the lattice

We wish to describe a method for formulating, on the lattice, field theories that contain Dirac particles with chiral couplings to gauge fields. As is well-known, the most straight-forward lattice transcription of the continuum action for a Dirac particle leads to the doubling problem: for every particle of a given chirality in the continuum theory, there appear on the lattice, in d dimensions, 2{sup d} particles, with equal numbers of particles of left- and right-handed chirality. No-go theorems, state that it is impossible to eliminate the doubling problem and still maintain an exact chiral gauge symmetry. Rather than follow an approach that attempts to circumvent the no-go theorems we, instead, explore the possibility of abandoning exact chiral symmetry.
Date: November 14, 1990
Creator: Bodwin, G.T. (Argonne National Lab., IL (USA)) & Kovacs, E.V. (Fermi National Accelerator Lab., Batavia, IL (USA))
System: The UNT Digital Library
Nuclear shell model calculations with non-local interactions (open access)

Nuclear shell model calculations with non-local interactions

It is becoming clearer with time that non-locality of the nucleon-nucleon interaction can play a significant role in nuclear properties. In this talk we review evidence for such non-locality. Then, using a Gaussian interaction, we discuss the effect of non-locality on two body matrix elements in the nuclear shell model. Finally, we mention some applications. For example, non-locality leads to faster convergence of off-diagonal matrix elements.
Date: October 14, 1990
Creator: Moszkowski, S.A. (California Univ., Los Angeles, CA (USA). Dept. of Physics); Bloom, S.D. & Resler, D.A. (Lawrence Livermore National Lab., CA (USA))
System: The UNT Digital Library
HYLIFE-II inertial confinement fusion reactor design (open access)

HYLIFE-II inertial confinement fusion reactor design

The HYLIFE-2 inertial fusion power plant design study uses a liquid fall, in the form of jets to protect the first structural wall from neutron damage, x rays, and blast to provide a 30-y lifetime. HYLIFE-1 used liquid lithium. HYLIFE 2 avoids the fire hazard of lithium by using a molten salt composed of fluorine, lithium, and beryllium (Li{sub 2}BeF{sub 4}) called Flibe. Access for heavy-ion beams is provided. Calculations for assumed heavy-ion beam performance show a nominal gain of 70 at 5 MJ producing 350 MJ, about 5.2 times less yield than the 1.8 GJ from a driver energy of 4.5 MJ with gain of 400 for HYLIFE-1. The nominal 1 GWe of power can be maintained by increasing the repetition rate by a factor of about 5.2, from 1.5 to 8 Hz. A higher repetition rate requires faster re-establishment of the jets after a shot, which can be accomplished in part by decreasing the jet fall height and increasing the jet flow velocity. Multiple chambers may be required. In addition, although not considered for HYLIFE-1, there is undoubtedly liquid splash that must be forcibly cleared because gravity is too slow, especially at high repetition rates. Splash removal can …
Date: December 14, 1990
Creator: Moir, Ralph W.
System: The UNT Digital Library
Organic acid modeling and model validation: Workshop summary (open access)

Organic acid modeling and model validation: Workshop summary

A workshop was held in Corvallis, Oregon on April 9--10, 1992 at the offices of E S Environmental Chemistry, Inc. The purpose of this workshop was to initiate research efforts on the entitled Incorporation of an organic acid representation into MAGIC (Model of Acidification of Groundwater in Catchments) and testing of the revised model using Independent data sources.'' The workshop was attended by a team of internationally-recognized experts in the fields of surface water acid-bass chemistry, organic acids, and watershed modeling. The rationale for the proposed research is based on the recent comparison between MAGIC model hindcasts and paleolimnological inferences of historical acidification for a set of 33 statistically-selected Adirondack lakes. Agreement between diatom-inferred and MAGIC-hindcast lakewater chemistry in the earlier research had been less than satisfactory. Based on preliminary analyses, it was concluded that incorporation of a reasonable organic acid representation into the version of MAGIC used for hindcasting was the logical next step toward improving model agreement.
Date: August 14, 1992
Creator: Sullivan, T.J. & Eilers, J.M.
System: The UNT Digital Library
Decoherence of multimode thermal squeezed coherent states (open access)

Decoherence of multimode thermal squeezed coherent states

It is well known that any multimode positive definite quadratic Hamiltonian can be transformed into a hamiltonian of uncoupled harmonic oscillators. Based on this theorem, the multimode thermal squeezed coherent states are constructed in terms of density operators. Decoherence of multimode thermal squeezed coherent states in investigated via the characteristic function and it is shown that the decohered (reduced) states are still thermal squeezed coherent states in general.
Date: August 14, 1992
Creator: Yeh, L.
System: The UNT Digital Library
Application of probabilistic risk assessment methods to incinerator design and permitting (open access)

Application of probabilistic risk assessment methods to incinerator design and permitting

The Consolidated Incineration Facility at the Savannah River Site is designed without emergency flue gas vents. The main components of this 18 million btu/hr facility are a rotary kiln and secondary combustion chamber, each with a code allowable internal pressure of 15 psig. The facility is designed to treat mixed waste. During the early stages of design it was judged on a qualitative basis that potential eventsthat might produce damaging overpressures were not credible. When these findings were questioned during subsequent design reviews, a probabilistic risk assessment was undertaken to provide a quantitative basis for decision making. The result was identification of design conditions leading to relatively high frequencies for a few event sequences in which the allowable pressure might be exceeded. Risk assessment assumptions and results were reviewed with design engineers and relatively simple improvements were identified that collectively reduced the frequency of overpressure to an acceptable level. This experience showed that the use of formalized risk assessment techniques can provide valuable insight leading to timely and cost-effective improvements in facility design and operating procedures. In this case, the program of analysis and follow-on improvements provided justification for incinerator operation without thermal relief devices.
Date: February 14, 1993
Creator: Brown, E.A.; McAfee, D.E. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Aabye, D.C. (Science Applications International Corp., Oak Ridge, TN (United States))
System: The UNT Digital Library
A 250-GHz CARM (Cyclotron Auto Resonance Maser) oscillator experiment driven by an induction linac (open access)

A 250-GHz CARM (Cyclotron Auto Resonance Maser) oscillator experiment driven by an induction linac

A 250-GHz Cyclotron Auto Resonance Maser (CARM) oscillator has been designed and constructed and will be tested using a 1-kA, 2-MeV electron beam produced by the induction linac at the Accelerator Research Center (ARC) facility of Lawrence Livermore National Laboratory (LLNL). The oscillator circuit was made to operate in the TE{sub 11} mode at ten times cutoff using waveguide Bragg reflectors to create an external cavity Q of 8000. Theory predicts cavity fill times of less than 30 ns (pulse length) and efficiencies approaching 20% is sufficiently low transverse electron velocity spreads are maintained (2%).
Date: September 14, 1990
Creator: Caplan, M.; Kulke, B.; Bubp, D.G. (Lawrence Livermore National Lab., CA (USA)); McDermott, D. & Luhmann, N. (California Univ., Los Angeles, CA (USA))
System: The UNT Digital Library
Infinite-mode squeezed coherent states and non-equilibrium statistical mechanics (phase-space-picture approach) (open access)

Infinite-mode squeezed coherent states and non-equilibrium statistical mechanics (phase-space-picture approach)

The phase-space-picture approach to quantum non-equilibrium statistical mechanics via the characteristic function of infinite- mode squeezed coherent states is introduced. We use quantum Brownian motion as an example to show how this approach provides an interesting geometrical interpretation of quantum non-equilibrium phenomena.
Date: August 14, 1992
Creator: Yeh, L.
System: The UNT Digital Library
The role of marketing in matching industry needs with technologies developed at Oak Ridge National Laboratory (open access)

The role of marketing in matching industry needs with technologies developed at Oak Ridge National Laboratory

National laboratories have limited resources to devote to the transfer of government-funded technologies to the commercial sector. Companies, too, face resource constraints in their attempt to identify and assimilate innovations which fit with their strategic objectives. For these reasons, persons engaged in technology transfer should attempt to identify laboratory developments which represent the best possible match with industry needs and focus their attention on those technologies which are most likely to make and impact in the marketplace. In a structured approach designed to meet this objective, Martin Marietta Energy Systems, which operates Oak Ridge National Laboratory for the Department of Energy, has established formal ties with the University of Tennessee Business School, to enhance the role of marketing for technology transfer. The school's MBA students continue to play a key role in the formulation and execution of plans designed to transform Oak Ridge technologies into new products, new jobs, and economic prosperity for US companies.
Date: November 14, 1990
Creator: Prosser, G.A.
System: The UNT Digital Library
Lattice automata models for earthquakes and frictional sliding (open access)

Lattice automata models for earthquakes and frictional sliding

This paper discusses lattice automata models for earthquakes and frictional sliding. (JEF)
Date: September 14, 1990
Creator: Rundle, J.B. (Lawrence Livermore National Lab., CA (USA)); Klein, W. (Boston Univ., MA (USA). Dept. of Physics) & Brown, S.R. (Sandia National Labs., Albuquerque, NM (USA))
System: The UNT Digital Library
Comments on the Interaction Between Theory and Experiment in High Energy Physics (open access)

Comments on the Interaction Between Theory and Experiment in High Energy Physics

This paper discusses work being conducted in High Energy Physics and Nuclear Physics where theory and experiment go hand in hand. Pion capture, proton-antiproton interactions, kaon-pion interactions and hypernuclei decay are discussed as examples. (LSP)
Date: September 14, 1990
Creator: Derrick, M.
System: The UNT Digital Library