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Comparing the Floating Point Systems, Inc. AP-190L to representative scientific computers: some benchmark results

Description: Results are presented of comparative timing tests made by running a typical FORTRAN physics simulation code on the following machines: DEC PDP-10 with KI processor; DEC PDP-10, KI processor, and FPS AP-190L; CDC 7600; and CRAY-1. Factors such as DMA overhead, code size for the AP-190L, and the relative utilization of floating point functional units for the different machines are discussed. 1 table.
Date: March 27, 1980
Creator: Brengle, T.A. & Maron, N.
Partner: UNT Libraries Government Documents Department
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Magnetic shielding design analysis

Description: Two passive magnetic-shielding-design approaches for static external fields are reviewed. The first approach uses the shielding solutions for spheres and cylinders while the second approach requires solving Maxwell's equations. Experimental data taken at LLNL are compared with the results from these shieldings-design methods, and improvements are recommended for the second method. Design considerations are discussed here along with the importance of material gaps in the shield.
Date: December 27, 1983
Creator: Kerns, J.A.; LaPaz, A.D. & Fabyan, J.
Partner: UNT Libraries Government Documents Department
open access

The excess flux in the cosmic submillimeter background radiation and the primordial deuterium abundance

Description: Recent measurements of the cosmic background radiation (CBR) show an enhanced flux in the submillimeter regime, compared to the spectrum of a 2.7 K blackbody. Thermal Comptonization of the relic radiation by a hot nonrelativistic plasma has long been known to produce distortions in the CBR spectrum, similar to what has now been observed. Heating of the primeval plasma to temperatures T {approximately} 10{sup 6} {minus} 10{sup 8} K could result from the injection of subcosmic ray protons at epoc… more
Date: October 27, 1989
Creator: Dermer, C. D.; Guessoum, N. (Lawrence Livermore National Lab., CA (USA) & National Aeronautics and Space Administration, Greenbelt, MD (USA). Lab. for High Energy Astrophysics)
Partner: UNT Libraries Government Documents Department
open access

Diffusion welding multifilament superconductive composites

Description: Diffusion welding is shown to be a feasible method for joining composites of niobium-titanium superconductor alloy filaments in a pure copper matrix. Good results were repeatedly obtained using 15/sup 0/ scarf joints welded with externally heated tooling and simple uniaxial compression loading in a conventional hydraulic press. Weld cycles of less than one hour total elapsed time were readily attainable. Through proper closed-die design, it was possible to increase welding pressure sufficiently… more
Date: February 27, 1978
Creator: Witherell, C.E.
Partner: UNT Libraries Government Documents Department
open access

Information systems for engineering sustainable development

Description: The ability of a country to follow sustainable development paths is determined to a large extent by the capacity or capabilities of its people and its institutions. Specifically, capacity-building in the UNCED terminology encompasses the country's human, scientific, technological, organizational, institutional, and resource capabilities. A fundamental goal of capacity-building is to enhance the ability to pose, evaluate and address crucial questions related to policy choices and methods of impl… more
Date: February 27, 1992
Creator: Leonard, R.S.
Partner: UNT Libraries Government Documents Department
open access

Technology requirements for fusion--fission reactors based on magnetic-mirror confinement

Description: Technology requirements for mirror hybrid reactors are discussed. The required 120-keV neutral beams can use positive ions. The magnetic fields are 8 T or under and can use NbTi superconductors. The value of Q (where Q is the ratio of fusion power to injection power) should be in the range of 1 to 2 for economic reasons relating to the cost of recirculating power. The wall loading of 14-MeV neutrons should be in the range of 1 to 2 MW/m/sup 2/ for economic reasons. Five-times higher wall loadin… more
Date: January 27, 1978
Creator: Moir, Ralph W.
Partner: UNT Libraries Government Documents Department
open access

The 40th AAAS Gordon Conference on nuclear chemistry

Description: I am pleased to speak at the Fortieth Gordon Conference on Nuclear Chemistry. I served as Chairman of the first Gordon Conference on Nuclear Chemistry held June 23--27, 1952, at New Hampton, New Hampshire. In my remarks, during which I shall quote from my journal, I shall describe some of the background leading up to the first Gordon Conference on Nuclear Chemistry and my attendance at the first seven Gordon Conferences during the period 1952 through 1958. I shall also quote my description of m… more
Date: June 27, 1991
Creator: Seaborg, G. T.
Partner: UNT Libraries Government Documents Department
open access

Seismic review of the R. E. Ginna Nuclear Power Plant as part of the Systematic Evaluation Program for the Nuclear Regulatory Commission

Description: This paper is a progress report on work at the Lawrence Livermore National Laboratory (LLNL) to perform a limited seismic reassessment of the Robert E. Ginna Nuclear Power Plant. The reassessment is being done for the Nuclear Regulatory Commission (NRC) as part of the Systematic Evaluation Program. The reassessment focuses generally on the reactor coolant pressure boundary and on those systems and components necessary to shut down the reactor safely and to maintain it in a safe shutdown conditi… more
Date: May 27, 1980
Creator: Murray, R. C.; Nelson, T. A.; Ng, D. S.; Liaw, C. Y.; Levin, H. A. & Cheng, T. M.
Partner: UNT Libraries Government Documents Department
open access

Some illustrations of stochasticity

Description: A complex, and apparently stochastic, character frequently can be seen to occur in the solutions to simple Hamiltonian problems. Such behavior is of interest, and potentially of importance, to designers of particle accelerators--as well as to workers in other fields of physics and related disciplines. Even a slow development of disorder in the motion of particles in a circular accelerator or storage ring could be troublesome, because a practical design requires the beam particles to remain conf… more
Date: December 27, 1977
Creator: Laslett, L.J.
Partner: UNT Libraries Government Documents Department
open access

Design of an electrostatic end-plugged plasma-confinement device

Description: A laboratory-scale experimental device having an outside diameter of 1.2 m has been designed to test the idea of electrostatic end plugging of an open-ended magnetic-field configuration. The configuration is a toroidal quadrupole having four very thin (less than 1-mm-thick) line cusps produced by four circular copper coils. Iron is used to concentrate the magnetic flux density to 2.0 T; without the use of iron, the power consumption, which is about 1 MW, would be about 25 times higher. The use … more
Date: September 27, 1977
Creator: Moir, R.W.; Dolan, T.J. & Barr, W.L.
Partner: UNT Libraries Government Documents Department
open access

Fabrication of cryogenic laser fusion targets

Description: Two novel techniques which produce a uniform frozen layer of deuterium-tritium on the inside surface of a glass microsphere are presented.
Date: September 27, 1977
Creator: Woerner, R.L. & Hendricks, C.D.
Partner: UNT Libraries Government Documents Department
open access

Dynamic Conductance of Carbon Nanotubes

Description: Article on dynamic conductance of carbon nanotubes.
Date: March 27, 2000
Creator: Roland, Christopher; Buongiorno Nardelli, Marco; Wang, Jian & Guo, Hong
Partner: UNT College of Arts and Sciences
open access

MTX/ELF II (Microwave Tokamak Experiment/ Electron Laser Facility II) microwave power measurements and calibration for the 2-GW, 140-GHZ, ELF II free-electron laser (FEL)

Description: We have developed techniques for measuring the power and frequency of the Electron Laser Facility (ELF) II free-electron laser (FEL) used for plasma heating experiments on the Microwave Tokamak Experiment (MTX). We also have designed a multichannel, 140-GHz receiver capable of measuring FEL power levels from 10 mW to 0.1 {mu}W within an accuracy of {plus minus}1 dB with a 50-dB dynamic range and a 2-ns response time. By using calibrated attenuators, we can measure power levels from 10 GW to 0.1… more
Date: September 27, 1989
Creator: Ferguson, S.W.; Stever, R.; Throop, A.; Felker, B. & Franklin, R.
Partner: UNT Libraries Government Documents Department
open access

Laser-fusion rocket for interplanetary propulsion

Description: A rocket powered by fusion microexplosions is well suited for quick interplanetary travel. Fusion pellets are sequentially injected into a magnetic thrust chamber. There, focused energy from a fusion Driver is used to implode and ignite them. Upon exploding, the plasma debris expands into the surrounding magnetic field and is redirected by it, producing thrust. This paper discusses the desired features and operation of the fusion pellet, its Driver, and magnetic thrust chamber. A rocket design … more
Date: September 27, 1983
Creator: Hyde, R.A.
Partner: UNT Libraries Government Documents Department
open access

Use of the Egret instrument in studies of the origin of the cosmic radiation

Description: This is a continuation of previous studies aimed at predicting spectral signatures of discrete cosmic-ray sources. In this paper, a formalism is developed for calculating gamma-ray spectra observed at Earth from the decay of neutral pions formed in collisions of cosmic-ray protons and ions with galactic gas and dust. The cosmic rays are assumed to be emitted by discrete sources, and their intensities and spectra are described by solutions to a diffusion equation. Calculations of spectral signat… more
Date: October 27, 1989
Creator: Dermer, C. D.
Partner: UNT Libraries Government Documents Department
open access

Transients - abnormal and otherwise

Description: Information is presented concerning transients in research reactors and nuclear power plants.
Date: September 27, 1983
Creator: Hendrie, J. M.
Partner: UNT Libraries Government Documents Department
open access

TMX magnets: mechanical design

Description: The Tandem Mirror Experiment (TMX) system, part of the Lawrence Livermore Laboratory magnetic mirror program incorporates in its design various types of coils or magnets. This paper describes the physical construction of each coil within the system as well as the structural design required for their support and installation.
Date: September 27, 1977
Creator: Hinkle, R. E.; Harvey, A. R.; Calderon, M. O.; Chargin, A. K.; Chen, F. F. K.; Denhoy, B. S. et al.
Partner: UNT Libraries Government Documents Department
open access

Detection and Measurement of Curium in the Marine Environment

Description: Transuranium elements have been introduced to the environment by a variety of ways including fallout from weapons testing, leakage from nuclear power reactors, waste effluent from nuclear fuel processing and leakage of radioactive waste from ocean dump sites. Several methods of curium detection and analysis in samples from marine ecosystems are contrasted and discussed in this paper.
Date: October 27, 1978
Creator: Schneider, D. L. & Livingston, H. D.
Partner: UNT Libraries Government Documents Department
open access

Microwave transport system for the MTX (Microwave Tokamak Experiment)

Description: This paper presents the design and construction, as well as the initial operation, of the Microwave Transmission System. The system consists of containment vessels, mirror boxes, mirrors, an alignment system, two turbo-molecular pump vacuum stations, and microwave source. Fifty-ns-length pulses of 6-MeV electrons pass through a free electron laser (FEL) wiggler. A 300 W extended interaction oscillator (EIO) of 140 GHz frequency supplies the seed signal for amplification in the wiggler. The elec… more
Date: September 27, 1989
Creator: Felker, B. & Ferguson, S.W.
Partner: UNT Libraries Government Documents Department
open access

Longitudinal compression of heavy-ion beams with minimum requirements on final focus

Description: A method is developed to compress a heavy-ion beam longitudinally in such a way that the compressed pulse has a constant line-charge density profile and uniform longitudinal momentum. These conditions may be important from the standpoint of final focusing. By realizing the similarity of the equations that describe the 1-D charged-particle motion to the equations that describe 1-D ideal gas flow, the evolution of lambda and the velocity tilt can be calculated using the method of characteristics … more
Date: May 27, 1986
Creator: Ho, D.D.M.; Bangerter, R.O.; Mark, J.W.K.; Brandon, S.T. & Lee, E.P.
Partner: UNT Libraries Government Documents Department
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