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in subjects: "Programming 990200* -- Mathematics & Computers"

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Pipelines programming paradigms: Prefab plumbing

Mastery of CMS Pipelines is a process of learning increasingly sophisticated tools and techniques that can be applied to your problem. This paper presents a compilation of techniques that can be used as a reference for solving similar problems

Date: August 1, 1991

Creator: Boeheim, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Application of automated deduction to the search for single axioms for exponent groups

We present new results in axiomatic group theory obtained by using automated deduction programs. The results include single axioms, some with the identity and others without, for groups of exponents 3, 4, 5 and 7, and a general form for single axioms for groups of odd exponent. The results were obtained by using the programs in three separate ways: as a symbolic calculator, to search for proofs,and to search for couterexamples. We also touch on relations between logic programming and automated … more

Date: February 11, 1992

Creator: McCune, W. & Wos, L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

On finding minimum-diameter clique trees

It is well-known that any chordal graph can be represented as a clique tree (acyclic hypergraph, join tree). Since some chordal graphs have many distinct clique tree representations, it is interesting to consider which one is most desirable under various circumstances. A clique tree of minimum diameter (or height) is sometimes a natural candidate when choosing clique trees to be processed in a parallel computing environment. This paper introduces a linear time algorithm for computing a minimum-… more

Date: August 1, 1991

Creator: Blair, J.R.S. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science) & Peyton, B.W. (Oak Ridge National Lab., TN (United States))

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

A domain decomposition algorithm for solving large elliptic problems

AN algorithm which efficiently solves large systems of equations arising from the discretization of a single second-order elliptic partial differential equation is discussed. The global domain is partitioned into not necessarily disjoint subdomains which are traversed using the Schwarz Alternating Procedure. On each subdomain the multigrid method is used to advance the solution. The algorithm has the potential to decrease solution time when data is stored across multiple levels of a memory hier… more

Date: January 1, 1991

Creator: Nolan, M.P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Parallel supercomputing: Advanced methods, algorithms and software for large-scale problems

Research has continued with excellent progress and new results on methodology and algorithms. We have also made supporting benchmark application studies on representative parallel computing architectures. Results from these research studies have been reported at scientific meetings, as technical reports and as journal publications. A list of pertinent presentations and publications is attached. The work on parallel element-by-element techniques and domain decomposition schemes has developed wel… more

Date: April 1, 1992

Creator: Carey, G.F. & Young, D.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Mapping method for generating three-dimensional meshes: past and present

Two transformations are derived in this paper. One is a mapping of a unit square onto a surve and the other is a mapping of a unit cube onto a three-dimensional region. Two meshing computer programs are then discussed that use these mappings. The first is INGEN, which has been used to calculate three-dimensional meshes for approximately 15 years. This meshing program uses an index scheme to number boundaries, surfaces, and regions. With such an index scheme, it is possible to control nodal poin… more

Date: January 1, 1982

Creator: Cook, W.A. & Oakes, W.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Progress Report: Network Based High Performance Concurrent Computing

The overall objectives of this project are to investigate research issues pertaining to programming tools and efficiency issues in network based concurrent computing systems. The basis for these efforts is the PVM project that evolved during my visits to Oak Ridge Laboratories under the DOE Faculty Research Participation program; I continue to collaborate with researchers at Oak Ridge on some portions of the project.

Date: 1991~

Creator: Sunderam, V. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Current status of link access control and encryption system

The purpose of this project is to develop necessary technologies for the secure protection of data communication networks. Data encryption equipment, using the federal government's Data Encryption Standard (DES) algorithm, was designed and developed. This equipment is the Link Access Control and Encryption (Link ACE) system. It protects unclassified sensitive data transmissions over unprotected lines between central computers and remote terminals. Link ACE units have been installed and are oper… more

Date: January 1, 1984

Creator: Springer, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Guidelines for technical reviews of software products

A guideline is given for technical review of products developed during a software life cycle. Purposes and benefits of reviews are given. Varieties of reviews, when they should take place, roles of the reviewers and products of the review are described.

Date: March 1, 1982

Creator: Wilburn, N.P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Toward a science of parallel computation

The evolution of parallel processing over the past several decades can be viewed as the development of a new scientific discipline. Parallel processing has been, and is, undergoing the same evolutionary stages that are common to the development of scientific disciplines in general: exploration, focusing, and maturity. That parallel processing is not yet a science can readily be appreciated by its lack of some of the characteristics typical of mature sciences, such as prescriptive terminology, c… more

Date: January 1, 1986

Creator: Worlton, W.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Measurement of memory access contentions in multiple vector processor systems

The purpose of this paper is to study delays encountered when several vector processors access a common memory. Such delays may be caused by access conflicts at the memory or by contentions within the network connection processors to common memory. Because such delays are potentially the limiting performance bottleneck of common memory architectures, it is important to understand how they depend on design parameters, in particular the number of processors serviced by the common memory, the degr… more

Date: January 1, 1991

Creator: Bucher, I. Y. & Simmons, M. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

New approaches to linear and nonlinear programming

During the last twelve months, research has concentrated on barrier- function methods for linear programming (LP) and quadratic programming (QP). Some ground-work for the application of barrier methods to nonlinearly constrained problems has also begun. In our previous progress report we drew attention to the difficulty of developing robust implementations of barrier methods for LP. We have continued to refine both the primal algorithm and the dual algorithm. We still do not claim that the barr… more

Date: March 1, 1990

Creator: Murray, W. & Saunders, M.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Scientific calculating system with a number-oriented microprocessor sequenced by a single component microcomputer

A scientific calculating system for large distributed-task processing systems and for small isolated intelligent data acquisition and instrumentation systems is established with a number-oriented microprocessor sequenced by a single-component microcomputer. A MOS/LSI number-oriented microprocessor provides the scientific calculating capability with Reverse Polish Notation data entry. Input data sequencing, computation processing, intermediate result comparison, answer display and/or answer feed… more

Date: January 1, 1977

Creator: Ethridge, C.D. & Worth, G.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Speakeasy linkules: plug compatible software

A universal computer language must be able to evolve to satisfy the needs of its current and future users. This paper describes such a language, called Speakeasy. The paper emphasizes those features of Speakeasy that relate to its naturalness and to its extensibility. Extensibility in the Speakeasy sense means the ability to bring diverse sets of routines under the umbrella of the system and thus make them available to users. Interfacing a routine through the construction of a linkable module, … more

Date: January 1, 1977

Creator: Cohen, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Matrix factorization on a hypercube multiprocessor

This paper is concerned with parallel algorithms for matrix factorization on distributed-memory, message-passing multiprocessors, with special emphasis on the hypercube. Both Cholesky factorization of symmetric positive definite matrices and LU factorization of nonsymmetric matrices using partial pivoting are considered. The use of the resulting triangular factors to solve systems of linear equations by forward and back substitutions is also considered. Efficiencies of various parallel computat… more

Date: August 1, 1985

Creator: Geist, G. A. & Heath, M. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Modeling node bandwidth limits and their effects on vector combining algorithms

Each node in a message-passing multicomputer typically has several communication links. However, the maximum aggregate communication speed of a node is often less than the sum of its individual link speeds. Such computers are called node bandwidth limited (NBL). The NBL constraint is important when choosing algorithms because it can change the relative performance of different algorithms that accomplish the same task. This paper introduces a model of communication performance for NBL computers … more

Date: January 13, 1992

Creator: Littlefield, R.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Text and graphics at Los Alamos: a system viewpoint

At Los Alamos National Laboratory, a computerized document preparation system is being developed to produce publication-quality documents integrating text and graphics. Mixing text and graphics involves a combination of two different technologies; thus the project has presented numerous and interesting challenges. The requirements, issues, solutions, and continuing concerns of the system development are described. The particular challenges encountered in fitting the document system into the Lab… more

Date: January 1, 1986

Creator: Vigil, M. & Bouchier, S.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Empirical results of a hybrid Monte Carlo method for the solution of Poisson's equation

The application of Monte Carlo techniques have considerable importance in solving computational problems that exhibit complex physical interactions and irregular spatial geometries. Yet equally important is the large computational parallelism that is inherent in these methods. With the current interest and emphasis on massively parallel computer systems, Monte Carlo methods would seem to be likely candidate for parallel implementation. However, parallelism in itself is only one metric for paral… more

Date: January 1, 1991

Creator: Hiromoto, R.E. & Brickner, R.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Sparse linear programming subprogram

This report describes a subprogram, SPLP(), for solving linear programming problems. The package of subprogram units comprising SPLP() is written in Fortran 77. The subprogram SPLP() is intended for problems involving at most a few thousand constraints and variables. The subprograms are written to take advantage of sparsity in the constraint matrix. A very general problem statement is accepted by SPLP(). It allows upper, lower, or no bounds on the variables. Both the primal and dual solutions a… more

Date: December 1, 1981

Creator: Hanson, R.J. & Hiebert, K.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

New approaches to linear and nonlinear programming

This report describes technical progress during the past twelve months on DOE Contract DE-FG-87ER25030 and requests support for the third year. The project involves study of the theoretical properties and computational performance of techniques that solve linear and nonlinear programs by means of nonlinear transformations. The group at the Systems Optimization Laboratory (SOL) were the first to recognize the connection between Karmarkar's projective method and the logarithmic barrier method. It… more

Date: September 1, 1988

Creator: Murray, W. & Saunders, M.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Distributed Implementation of Functional Program Evaluation

In this paper, we explore the potential of the functional model, particularly as it pertains to architecture. In Section 2, we describe the graph-reduction operational model of computation and its relation to AI problems. In Section 3, we discuss a class of architectures that implement graph reduction and a prototype implementation in this class being developed at Los Alamos. Finally, we speculate on the applicability of graph reduction to some other classes of architecture.

Date: January 1, 1985

Creator: Fasel, J.H.; Douglass, R.J.; Michelsen, R. & Hudak, P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Terminal-state dynamic programming: quadratic costs, linear differential equations

No Description Available.

Date: July 1, 1969

Creator: Collins, D.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Iterative methods for nonsymmetric systems on MIMD machines

A wide variety of physical phenomena arising within many scientific disciplines can be described by systems of coupled partial differential equations (PDEs). The numerical approximation of these PDEs often involves the solution of a system of algebraic equations (possibly nonlinear) which are typically large, sparse and nonsymmetric. The increasing computational demands required by the solution of such complex scientific applications has motivated the current direction toward large-scale parall… more

Date: October 16, 1990

Creator: Shadid, J.N. & Tuminaro, R.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Planning under uncertainty solving large-scale stochastic linear programs

For many practical problems, solutions obtained from deterministic models are unsatisfactory because they fail to hedge against certain contingencies that may occur in the future. Stochastic models address this shortcoming, but up to recently seemed to be intractable due to their size. Recent advances both in solution algorithms and in computer technology now allow us to solve important and general classes of practical stochastic problems. We show how large-scale stochastic linear programs can … more

Date: December 1, 1992

Creator: Infanger, G.

Item Type: Report

Partner: UNT Libraries Government Documents Department