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in subjects: "Algorithms"

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DWPF waste glass Product Composition Control System

The Defense Waste Processing Facility (DWPF) will be used to blend aqueous radwaste (PHA) with solid radwaste (Sludge) in a waste receipt vessel (the SRAT). The resulting SRAT material is transferred to the SME an there blended with ground glass (Frit) to produce a batch of melter feed slurry. The SME material is passed to a hold tank (the MFT) which is used to continuously feed the DWPF melter. The melter. The melter produces a molten glass wasteform which is poured into stainless steel canist… more

Date: January 1, 1992

Creator: Brown, K.G. & Postles, R.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solar-thermal energy conversion and storage: cyclohexane dehydrogenation. Progress report, 30 September 1977-30 June 1978

The objective of this project is to provide research support for the benzene/cyclohexane heat pipe development program at Sandia. The kinetics of the cyclohexane decomposition (energy collection) reaction over a commercially available naphtha reforming catalyst (RD-150, Englehard Industries) in the temperature range 400 to 800/sup 0/F and pressures of 1 to 40 atmospheres were measured. Significant amounts of side products such as toluene and butane were identified at temperatures above 550/sup … more

Date: July 1, 1978

Creator: Ritter, A.B.; DeLancey, G.B.; Schneider, J. & Silla, H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Geostatistics project of the national uranium resource evaluation program. Progress report, October 1979-March 1980

During the period covered by this report, the authors investigated the serial properties of aerial radiometric data. Results were applied to the choice of minimum segment width in the maximum variance segments algorithm and to the use of aerial radiometric data in the design of ground sampling experiments. The report also presents the results of a comparison of normal and lognormal percentile estimation techniques. Twenty-two quadrangles are being analyzed in the search for a uranium favorabili… more

Date: August 1, 1980

Creator: Campbell, K.; Bement, T. R.; Howell, J. A.; Beckman, R. J.; Jackson, K. & Buslee, P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Plutonium isotopic analysis of highly enriched mixed oxides

We investigated the analysis method used by the International Atomic Energy Agency (IAEA) to determine the plutonium isotopic composition of highly enriched mixed oxides (MOX). The IAEA currently uses the Cicero multichannel analyzer and the IAEAPU algorithm for its analysis. In our investigation the plutonium isotopic measurements were found to be good for PuO/sub 2/ powder or low-enriched MOX, but acceptable for highly enriched MOX in IAEA special nuclear material (SNM) accountability applica… more

Date: August 1, 1986

Creator: Clement, S. D. & Augustson, R. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Jet rates from deep inelastic muon scattering in the W range of 15 to 35 GeV

Production rates of forward jets in deep inelastic muon scattering are studied using the JADE jet finding algorithm. The evolution of di-jet rates with W is compared to QCD first order predictions in the W range of 15 to 25 GeV. 7 refs., 3 figs.

Date: August 1, 1991

Creator: Salgado, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Computing tools for accelerator design

An algorithm has been developed that calculates and obtains information about nonlinear contributions in accelerators. The comparison of the results obtained from this program ''NONLIN'' and HARMON is discussed and illustrated for the SSC-CDR clustered lattices.

Date: June 1, 1986

Creator: Parsa, Z.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Stepwise development of algorithms for the nonlinear projection methods

No Description Available.

Date: April 1, 1975

Creator: Georg, D.D. & Keller, R.F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Multi-grid and ICCG for problems with interfaces

Computation times for the multi-grid (MG) algorithm, the incomplete Cholesky conjugate gradient (ICCG) algorithm (J. Comp. Phys. 26, 43-65 (1978); Math. Comp. 31, 148-162 (1977)), and the modified ICCG (MICCG) algorithm (BIT 18, 142-156 (1978)) to solve elliptic partial differential equations are compared. The MICCG and ICCG algorithms are more robust than the MG for general positive definite systems. A major advantage of the MG algorithm is that the structure of the problem can be exploited to… more

Date: January 1, 1980

Creator: Dendy, J.E. & Hyman, J.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An iterative algorithm to produce a positive definite correlation matrix from an approximate correlation matrix (with a program user's guide)

This report contains an explanation of an algorithm that, when executed, will operate on any symmetric approximate correlation matrix by iteratively adjusting the eigenvalues of this matrix. The objective of this algorithm is to produce a valid, positive definite, correlation matrix. Also a description of a program (called POSDEF) which implements the algorithm is given.

Date: June 1, 1982

Creator: Iman, R.L. & Davenport, J.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Simulation of ethylbenzene dehydrogenation in microporous catalytic membrane reactors

Current state-of-the-art inorganic oxide membranes offer the potential of being modified to yield catalytic properties. The resulting modules may be configured to simultaneously induce catalytic reactions with product concentration and separation in a single processing step. Processes utilizing such catalytically active membrane reactors have the potential for dramatically increasing yield of reactions which are currently limited by either thermodynamic equilibria, product inhibition, or kineti… more

Date: April 1, 1989

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

An optimized algorithm for solving the nodal diffusion method on shared memory multiprocessors

Nodal methods play a special role in reactor physics calculations. In recent papers the high computational efficiency of nodal methods has been established and the development of more efficient algorithms tailored to the advanced architectures of modern day computers proposed. The rapidly changing architectures of today's computer influence the way codes have to be programmed so that reasonable speed up and efficiency are attained. We have applied these concepts in solving the one-group neutron… more

Date: January 1, 1990

Creator: Kirk, B.L. & Azmy, Y.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

SOILD: A computer model for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil

The SOLID computer model was developed for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil. It is designed to assess external doses under various exposure scenarios that may be encountered in environmental restoration programs. The models four major functional features address (1) dose versus source depth in soil, (2) shielding of clean cover soil, (3) area of contamination, and (4) nonuniform distribution of sources. The model is also capab… more

Date: January 1, 1991

Creator: Chen, S. Y.; LePoire, D.; Yu, C. (Argonne National Lab., IL (United States)); Schafetz, S. (Rockland Community Coll., Suffern, NY (United States)) & Mehta, P. (Fayetteville State Univ., NC (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Frequency-domain stress prediction algorithm for the LIFE2 fatigue analysis code

The LIFE2 computer code is a fatigue/fracture analysis code that is specialized to the analysis of wind turbine components. The numerical formulation of the code uses a series of cycle mount matrices to describe the cyclic stress states imposed upon the turbine. However, many structural analysis techniques yield frequency-domain stress spectra and a large body of experimental loads (stress) data is reported in the frequency domain. To permit the analysis of this class of data, a Fourier analysi… more

Date: January 1, 1992

Creator: Sutherland, H. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Degenerate perturbation theory

The algebraic structure of degenerate Rayleigh-Schroedinger perturbation theory is reviewed. There are a number of different but equivalent algorithms which generate this perturbation series; we argue that the frequent need to carry out infinite-order partial summations selects one of these algorithms as the most efficient. Recent developments include coupled-cluster formulations for open shells, a new diagrammatic representation, and the concept of incomplete model subspaces. These subjects ar… more

Date: January 1, 1982

Creator: Brandow, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Implementation of a hidden line and surface algorithm

The implementation of a 3-dimensional hidden line and surface algorithm discussed by Hamlin and Gear (NASA Langley Research Report 77-1) is described, and its advantages and disadvantages are examined. This algorithm is organized so that data can be preprocessed to speed display computations and so that the display is generated in a form suitable for a raster scan, refresh display. The version of the program described here is a hidden-line program, but the underlying algorithm is the same for b… more

Date: August 1, 1980

Creator: Schweitzer, M.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Challenge problems focusing on equality and combinatory logic: Evaluating automated theorem-proving programs

In this paper, we offer a set of problems for evaluating the power of automated theorem-proving programs and the potential of new ideas. Since the problems published in the proceedings of the first CADE conference proved to be so useful, and since researchers are now far more disposed to implementing and testing their ideas, a new set of problems to complement those that have been widely studied is in order. In general, the new problems provide a far greater challenge for an automated theorem-p… more

Date: January 1, 1988

Creator: Wos, L. & McCune, W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Method to rapidly tune the halo spoilers of the tevatron muon beam

An active shield has been constructed which forms a sharp magnetic edge around the central core of useful muons and sweeps the envelope of halo muons (those that enter the aperture of an experiment without having passed through the momentum tagging system) radially away from beam center. Two types of halo scrapers have been employed in this shield: conventional toroidal magnets and a newly developed magnetic element called ''mupipe''. The mupipes have eight degrees of motion, so attempting to t… more

Date: September 1, 1986

Creator: Ojeda, Y.; Scott, B.; Malensek, A. & Morfin, J.G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Framework for control system development

Control systems being developed for the present generation of accelerators will need to adapt to changing machine and operating state conditions. Such systems must also be capable of evolving over the life of the accelerator operation. In this paper we present a framework for the development of adaptive control systems.

Date: November 1, 1991

Creator: Cork, C. & Nishimura, Hiroshi.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A survey of air flow models for multizone structures

Air flow models are used to simulate the rates of incoming and outgoing air flows for a building with known leakage under given weather and shielding conditions. Additional information about the flow paths and air-mass flows inside the building can only by using multizone air flow models. In order to obtain more information on multizone air flow models, a literature review was performed in 1984. A second literature review and a questionnaire survey performed in 1989, revealed the existence of 5… more

Date: March 1, 1991

Creator: Feustel, H.E. & Dieris, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Some numerical reslts on best uniform polynomial approximation of. chi. sup. alpha. on (0,1)

Let {alpha} be a positive number, and let E{sub n}(chi{sup {alpha}}; (0,1)) denote the error of best uniform approximation to {chi}{sup {alpha}}, by polynomials of degree at most n, on the interval (0,1). The Russian mathematician S.N. Bernstein established the existence of a nonnegative constant {Beta}({alpha}) such that {Beta}({alpha}):= {sub n{yields}{infinity}lim(2n){sup 2{alpha}}E{sub n}({chi}{sup {alpha}};(0.1)). In addition, Bernstein showed that {Beta}{alpha} < {Gamma}(2{alpha}){vert ba… more

Date: January 1, 1992

Creator: Carpenter, A.J. & Varga, R.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Digital simulation and modeling of nonlinear stochastic systems

Digitally generated solutions of nonlinear stochastic systems are not unique, but depend critically on the numerical integration algorithm used. Some theoretical and practical implications of this dependence are examined. The Ito-Stratonovich controversy concerning the solution of nonlinear stochastic systems is shown to be more than a theoretical debate on maintaining Markov properties as opposed to utilizing the computational rules of ordinary calculus. The theoretical arguments give rise to … more

Date: January 1, 1980

Creator: Richardson, J. M. & Rowland, J. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Multigroup formalism for evaluation of continuous slowing down theory parameters

Continuous slowing down theory calculations have been found to yield significant discrepancies in the presence of strong absorption. An algorithm has been formulated for evaluating continuous slowing down theory parameters which should be applicable for cases with strong absorption. Excellent agreement with more precise calculations is obtained when the new parameters are used.

Date: January 1, 1975

Creator: Parvez, A. & Becker, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Detection and diagnosis of abnormal transients in nuclear power plants

This document describes a simulation-based algorithm that combines fuzzy logic with macroscopic conservation equations to diagnose multiple-failure events subject to uncertainties in transient data. Clusters of single-failure data points of similar characteristics are obtained through a pattern recognition algorithm and the cluster centers are combined in the space of macroscopic inventory derivatives to generate multiple-failure cluster centers. A fuzzy membership function is used to represent… more

Date: January 1, 1991

Creator: Lee, J. C.; Rank, P. J.; Hawkes, E.; Wehe, D. K. (Michigan Univ., Ann Arbor, MI (United States). Dept. of Nuclear Engineering) & Reifman, J. (Argonne National Lab., IL (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

ADIFOR: Fortran source translation for efficient derivatives

The numerical methods employed in the solution of many scientific computing problems require the computation of derivatives of a function f: R{sup n} {yields} R{sup m}. Both the accuracy and the computational requirements of the derivative computation are usually of critical importance for the robustness and speed of the numerical method. ADIFOR (Automatic Differentiation In FORtran) is a source translation tool implemented using the data abstractions and program analysis capabilities of the Pa… more

Date: January 1, 1992

Creator: Bischof, C.; Corliss, G.; Griewank, A.; Hovland, P. (Argonne National Lab., IL (United States)) & Carle, A. (Rice Univ., Houston, TX (United States). Center for Research on Parallel Computation)

Item Type: Article

Partner: UNT Libraries Government Documents Department