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Space propulsion by fusion in a magnetic dipole

Description: The unique advantages of fusion rocket propulsion systems for distant missions are explored using the magnetic dipole configurations as an example. The dipole is found to have features well suited to space applications. Parameters are presented for a system producing a specific power of kW/kg, capable of interplanetary flights to Mars in 90 days and to Jupiter in a year, and of extra-solar-system flights to 1000 astronomical units (the Tau mission) in 20 years. This is about 10 times better spe… more
Date: July 15, 1991
Creator: Teller, E.; Glass, A.J.; Fowler, T.K. (Lawrence Livermore National Lab., CA (United States)); Hasegawa, A. (AT and T Bell Labs., Murray Hill, NJ (United States)) & Santarius, J.F. (Wisconsin Univ., Madison, WI (United States). Fusion Technology Inst.)
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Partner: UNT Libraries Government Documents Department
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Deconvolution using a neural network

Description: Viewing one dimensional deconvolution as a matrix inversion problem, we compare a neural network backpropagation matrix inverse with LMS, and pseudo-inverse. This is a largely an exercise in understanding how our neural network code works. 1 ref.
Date: November 15, 1990
Creator: Lehman, S.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Emittance measurement in a magnetic field

Description: Emittance can be measured by intercepting an electron beam on a range thick plate and then observing the expansion of beamlets transmitted through small holes. The hole size is selected to minimize space charge effects. In the presence of a magnetic field the beamlets have a spiral trajectory and the usual field free formulation must be modified. To interpret emittance in the presence of a magnetic field an envelope equation is derived in the appropriate rotating frame. 1 ref.
Date: April 15, 1991
Creator: Boyd, J.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simulations of NOVA direct-drive hydrodynamics experiments

Description: Directly driven Rayleigh-Taylor instability growth experiments being performed on NOVA have been simulated using the computer code, LASNEX. Foils with single-wavelength imposed surface perturbations have been driven with a single beam of 0.53 {mu}m light, employing smoothing by spectral dispersion (SSD). In addition to simulating foils with imposed surface perturbations, we have simulated flat foils driven by beams with time-dependent intensity modulation resulting from the NOVA implementation … more
Date: April 15, 1991
Creator: Weber, S. V, & Glendinning, S. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The single antenna interferometer

Description: Air and space borne platforms using synthetic aperture radars (SAR) have made interferometric measurements by using either two physical antennas mounted on one air-frame or two passes of one antenna over a scene. In this paper, a new interferometric technique using one pass of a single-antenna SAR system is proposed and demonstrated on data collected by the NASA-JPL AirSAR. Remotely sensed L-band microwave data are used to show the sensitivity of this technique to ocean surface features as well… more
Date: January 15, 1990
Creator: Fitch, J.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Physics issues in the design of a recirculating induction accelerator for heavy ion fusion

Description: A substantial savings in size and cost over a linear machine may be achieved in an induction accelerator in which a heavy ion beam makes many (< {approximately} 50) passes through one or more circular induction accelerators. We examine how the requirement of high beam quality and the requirement of pulse simultaneity at the target constrain the design of such an accelerator. Some of the issues that we have considered include beam interactions with residual gas, beam-beam charge exchange, emitta… more
Date: April 15, 1991
Creator: Barnard, J. J.; Newton, M. A.; Reginato, L. L.; Sharp, W. M. & Yu, S. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of spherical geometry finite element transport solutions in the thick diffusion limit

Description: An asymptotic analysis if performed on a family of discontinuous finite element methods (DFEMs) for spherical geometry transport. It is found that transport methods of this type transition into discrete versions of the spherical geometry diffusion equation in the thick diffusion limit with boundary conditions that may, in general, be inaccurate. A linear DFEM method has been designed such that its asymptotic diffusion boundary conditions are accurate. In a related development, the asymptotic di… more
Date: January 15, 1991
Creator: Palmer, T.S. (Michigan Univ., Ann Arbor, MI (USA). Dept. of Nuclear Engineering) & Adams, M.L. (Lawrence Livermore National Lab., CA (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ASSESS (Analytic System and Software for Evaluating Safeguards and Security) update: Current status and future developments

Description: The Analytic System and Software for Evaluating Safeguards and Security (ASSESS) has been released for use by DOE field offices and their contractors. In October, 1989, we offered a prototype workshop to selected representatives of the DOE community. Based on the prototype results, we held the first training workshop at the Central Training Academy in January, 1990. Four additional workshops are scheduled for FY 1990. ASSESS is a state-of-the-art analytical tool for management to conduct integr… more
Date: July 15, 1990
Creator: Al-Ayat, R.A. (Lawrence Livermore National Lab., CA (USA)); Cousins, T.D. (USDOE, Washington, DC (USA)) & Hoover, E.R. (Sandia National Labs., Albuquerque, NM (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Order-disorder phenomena in complex alloys: The case of A15-based substitutional alloys

Description: We first discuss the applicability of the Generalized Perturbation Method to the study of ordering phenomena in complex alloys for which stability properties are electronically driven. In particular, according to previous work, it is recalled that a 3D-generalized Ising model is appropriate to address the problem of configurational order in A15-based substitutional alloys. A ground state analysis of this model, including 1st, 2nd, and weak 3rd and 7th pair interactions, generates two new ordere… more
Date: August 15, 1990
Creator: Turchi, P.E.A. (Lawrence Livermore National Lab., CA (USA)) & Finel, A. (Office National d'Etudes et de Recherches Aerospatiales (ONERA), 92 - Chatillon (France))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermomechanical properties of Cr:Tm:Ho:Y sub 3 Al sub 5 O sub 12

Description: The thermomechanical properties of Cr:Ho:Tm:Y{sub 3}Al{sub 5}O{sub 12} have been measured and compared to similar measurements on Nd:Y{sub 3}Al{sub 5}O{sub 12}. We find that, in general, the properties are similar, with the single exception being thermal diffusivity. Nd:YAG has substantially higher thermal diffusivity than Cr:Tm:Ho:YAG. Consequently, the intrinsic thermal stress resistance figure of merit which governs a materials resistance to fracture in the presence of a steady thermal gradi… more
Date: May 15, 1990
Creator: Marion, J.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Anatomy of a disruption in MTX (Microwave Tokamak Experiment)

Description: Disruptions are observed in the Microwave Tokamak Experiment, MTX (nee Alcator C), over a wide range of plasma parameters. Indeed, disruptions often occur far from the boundaries of the operating space as defined by Hugill and l{sub i}-q plots. Despite this, the general behavior during the disruptive process is generally similar whatever the operating parameters. This report will describe one disruption in detail in order to provide a detailed anatomy of the event.
Date: October 15, 1990
Creator: Hooper, E. B.; Casper, T. A.; Lasnier, C. J.; Makowski, M. A.; Meyer, W. H.; Moller, J. M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

(International Thermonuclear Experimental Reactor support)

Description: This report summarizes the activities under LLNL Purchase Order B089367, the purpose of which is to support the University/Lawrence Livermore National Laboratory Magnetic Fusion Program by evaluating the status of research relative to other national and international programs and assist in long-range plans and development strategies for magnetic fusion in general and for ITER in particular.'' Two specific subtasks are included: to review the LLNL Magnet Technology Development Program in the con… more
Date: October 15, 1990
Creator: Dean, S. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Improving line detector by wedge filtering in the Fourier power spectrum domain

Description: This paper reports on the work being performed for the ship wake detection effort. We show that improvements in the detectability of line features in noisy images, using the correlation-spectral line detector, can be achieved through the judicious choice of a wedge filter in the Fourier power spectrum (FPS) domain. 3 refs., 7 figs.
Date: November 15, 1990
Creator: Lehman, S.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Superpressure Stratospheric Vehicle

Description: Our need for wide-band global communications, earth imaging and sensing, atmospheric measurements and military reconnaissance is extensive, but growing dependence on space-based systems raises concerns about vulnerability. Military commanders require space assets that are more accessible and under local control. As a result, a robust and low cost access to space-like capability has become a national priority. Free floating buoyant vehicles in the middle stratosphere can provide the kind of cost… more
Date: September 15, 1990
Creator: Chocol, C.; Robinson, W. & Epley, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The logic behind thick, liquid-walled, fusion concepts

Description: It may be possible to surround the region where fusion reactions are taking place with a neutronically thick liquid blanket which has penetrations that allow only a few tenths of a percent of the neutrons to leak out. Even these neutrons can be attenuated by adding an accurately placed liquid or solid near the target to shadow-shield the beam ports from line-of-sight neutrons. The logic of such designs are discussed and their evolution is described with examples applied to both magnetic and ine… more
Date: April 15, 1994
Creator: Moir, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Convection in Type 2 supernovae

Description: Results are presented here from several two dimensional numerical calculations of events in Type II supernovae. A new 2-D hydrodynamics and neutrino transport code has been used to compute the effect on the supernova explosion mechanism of convection between the neutrinosphere and the shock. This convection is referred to as exterior convection to distinguish it from convection beneath the neutrinosphere. The model equations and initial and boundary conditions are presented along with the simul… more
Date: October 15, 1993
Creator: Miller, D. S.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

The PHENIX experiment at RHIC

Description: Later this decade the Relativistic Heavy Ion Collider (RHIC) will be built at Brookhaven National Laboratory. Its goal will be to accelerate and collide Au beams at 100 GeV/c in an attempt to create a Quark Gluon Plasma (QGP). The PHENIX detector aims to detect the QGP through its leptonic and hadronic signatures. We describe here its physics capabilities and the details of the apparatus designed to pick out rare leptonic signatures from among hadronic multiplicities of up to 1500 particles per… more
Date: December 15, 1993
Creator: Tonse, S. R. & Thomas, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mutagenic activity and heterocyclic amine content of the human diet

Description: The mutagenic activity and the mass amount of heterocyclic amines responsible for the mutagenic activity have been measured in some cooked foods. Cooked meats are the predominant source of mutagenic activity in the diet with values ranging from 0 to 10,000 revertants per gram reported in the Ames/Salmonelia test with strain TA98. Several heterocyclic amines are present and have been quantified using solid-phase extraction followed by HPLC. Frying at higher temperatures and for longer times prod… more
Date: January 15, 1993
Creator: Knize, M. G.; Dolbeare, F. A.; Cunningham, P. L. & Felton, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The decade of innovation: Los Alamos, Livermore, and national security decision making in the 1950s. Workshop executive summary

Description: This report discusses the following topics; establishment and growth of the laboratories and the struggle for Livermore; technology and weapons development; and challenges to unbridled technological development--the laboratories and arms control.
Date: June 15, 1994
Creator: Greb, G. A. & Adkins, K.
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Partner: UNT Libraries Government Documents Department
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Base hydrolysis of HMX/DMSO solutions

Description: The authors investigated the decomposition of HMX or PBX-9404 as a 25% solution in DMSO by treatment with aqueous base solutions. They investigated investigated two concentrations of NaOH solutions, 40% NaOH and 2N NaOH. {sup 1}H-nmr spectroscopy was chosen to follow the decomposition by {sup 1}H-nmr spectroscopy, watching the disappearance of the -CH{sub 2}-absorbance of HMX at 6.2 ppm. The 40% NaOH solution is initially immiscible with the DMSO solution but becomes miscible as it reacts. The … more
Date: March 15, 1994
Creator: Pagoria, P. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Toward a high performance distributed memory climate model

Description: As part of a long range plan to develop a comprehensive climate systems modeling capability, the authors have taken the Atmospheric General Circulation Model originally developed by Arakawa and collaborators at UCLA and have recast it in a portable, parallel form. The code uses an explicit time-advance procedure on a staggered three-dimensional Eulerian mesh. The authors have implemented a two-dimensional latitude/longitude domain decomposition message passing strategy. Both dynamic memory mana… more
Date: February 15, 1993
Creator: Wehner, M. F.; Ambrosiano, J. J.; Brown, J. C.; Dannevik, W. P.; Eltgroth, P. G.; Mirin, A. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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System response of a DOE Defense Program package in a transportation accident environment

Description: The system response in a transportation accident environment is an element to be considered in an overall Transportation System Risk Assessment (TSRA) framework. The system response analysis uses the accident conditions and the subsequent accident progression analysis to develop the accident source term, which in turn, is used in the consequence analysis. This paper proposes a methodology for the preparation of the system response aspect of the TSRA.
Date: October 15, 1992
Creator: Chen, T. F.; Hovingh, J. & Kimura, C. Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

ITER-hard Toroidal Field coil structural analysis

Description: The High Aspect Ratio Design (HARD) for the International Thermonuclear Experimental Reactor (ITER) has Toroidal Field (TF) coils that are farther out from the center of the Toroidal ring and more elongated than the previous design (CDA). These coils should see higher forces than in CDA and were designed accordingly. The objective of this work, conducted at LLNL and the MIT Plasma Fusion Center, was to determine whether stress levels in the ITER-HARD design are acceptable. A global finite eleme… more
Date: October 15, 1992
Creator: Wineman, S. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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