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Search of the VAXintosh customizing VMS V4. 0 for DCL windows

Description: This paper will describe methods of implementing such windows for: (1) DCL and MAIL; (2) Command Procedures; and (3) the VMS V4.0 editors EDT, LSE and TPU. While VMS and a number of utilities have the SPAWN command available to the user, the window interface to be described has been found in practice to be simpler to use because: (1) windows are consistently invoked with a single key command; and (2) confusion is minimized because one always knows if one is in a window.
Date: January 1, 1985
Creator: Downward, J.G.
Partner: UNT Libraries Government Documents Department

A tight and explicit representation of Q in sparse QR factorization

Description: In QR factorization of a sparse m{times}n matrix A (m {ge} n) the orthogonal factor Q is often stored implicitly as a lower trapezoidal matrix H known as the Householder matrix. This paper presents a simple characterization of the row structure of Q, which could be used as the basis for a sparse data structure that can store Q explicitly. The new characterization is a simple extension of a well known row-oriented characterization of the structure of H. Hare, Johnson, Olesky, and van den Driessche have recently provided a complete sparsity analysis of the QR factorization. Let U be the matrix consisting of the first n columns of Q. Using results from, we show that the data structures for H and U resulting from our characterizations are tight when A is a strong Hall matrix. We also show that H and the lower trapezoidal part of U have the same sparsity characterization when A is strong Hall. We then show that this characterization can be extended to any weak Hall matrix that has been permuted into block upper triangular form. Finally, we show that permuting to block triangular form never increases the fill incurred during the factorization.
Date: May 1, 1992
Creator: Ng, E.G. & Peyton, B.W.
Partner: UNT Libraries Government Documents Department

Confidence intervals for the odds ratio in case-control studies: the state of the art

Description: Many approximate procedures are available for setting confidence limits around the odds ratio in a four-fold table. A number of them are analyzed according to three criteria: close agreement between the actual and the nominal confidence levels; exact agreement with a hypothesis test for or against significance; and relative simplicity in calculation. The procedure due to Cornfield comes closer to satisfying all three criteria than any of the others examined. Formulas are provided for an iterative solution to Cornfield's equations.
Date: April 1, 1978
Creator: Fleiss, J.L.
Partner: UNT Libraries Government Documents Department

Axymptotic normality of X/sup 2/ in mxn tables with n large and small cell expectations

Description: Asymptotic normality for chi/sup 2/ used as a test for homogeneity is established under nonstandard conditions. The case of an mxn table with m fixed and the total number of observations proportional to n is studied for n large. Results are obtained under very mild assumptions on the marginal totals.
Date: January 1, 1977
Creator: Cuzick, J.
Partner: UNT Libraries Government Documents Department

Teaching old Fortran programmers new tricks

Description: For a number of valid reasons, Fortran remains in widespread use. It can be difficult to get long-time Fortran programmers to accept the use of new software tools that are increasingly required to lower software costs. In order to gain acceptance for a new software tool, it is necessary for it to be easy to learn and use, as well as to provide new benefits. In the process of introducing the use of the Ratfor preprocessor for Fortran, a number of useful guidelines were defined for gaining the acceptance of any new software tool in an existing environment.
Date: January 1, 1980
Creator: Wampler, B. E.
Partner: UNT Libraries Government Documents Department

Visual tools and languages: Directions for the '90s

Description: We identify and discuss three domains where we believe that innovative application of visual programming languages is likely to make a significant impact in the near term: concurrent computing, computer-based assistance for people with disabilities, and the multimedia/multimodal environments of tomorrow in which it will be possible to hear and physically interact with information as well as see it. 33 refs., 3 figs.
Date: January 1, 1991
Creator: Glinert, E.P. (Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Computer Science); Blattner, M.M. (Lawrence Livermore National Lab., CA (United States)) & Frerking, C.J. (California Univ., Davis, CA (United States))
Partner: UNT Libraries Government Documents Department

A sendmail. cf scheme for a large network

Description: 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.
Partner: UNT Libraries Government Documents Department

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

Description: 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 reasoning.
Date: February 11, 1992
Creator: McCune, W. & Wos, L.
Partner: UNT Libraries Government Documents Department

Floating point hardware emulator for RSX-11D

Description: An RSX-11D task was written to simulate the FP-11 floating point hardware on systems that lack this hardware. The simulation is transparent to tasks using floating point instructions. All normal features of the hardware are simulated exactly, including its action on exception conditions. The emulator is a privileged task occupying about 2.7K words of memory. When it is loaded and run, it sets up a linkage to intercept the reserved instruction trap before it reaches the executive, and route it to a service routine that can decode and simulate the floating point instruction set. The results of a benchmark timing test are given, as are notes on converting the emulator to run under RSX-11M. 1 figure, 2 tables.
Date: January 1, 1977
Creator: Kellogg, M. & Long, M.
Partner: UNT Libraries Government Documents Department

Current status of link access control and encryption system

Description: 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 operational in the Department of Energy's Central Personnel Clearance Index (CPCI) system.
Date: January 1, 1984
Creator: Springer, E.
Partner: UNT Libraries Government Documents Department

Modeling the behavior of the computer-assisted instruction user

Description: The field of computer-assisted instruction CAI contains abundant studies on effectiveness of particular programs or systems. However, the nature of the field is such that the computer is the focus of research, not the users. Few research studies have focused on the behavior of the individual CAI user. Morgan (1981) stated that descriptive studies are needed to clarify what the important phenomena of user behavior are. The need for such studies is particularly acute in computer-assisted instruction. Building a behavioral model would enable us to understand problem-solving strategies and rules applied by the user during a CAI experience. Also, courseware developers could use this information to design tutoring systems that are more responsive to individual differences than our present CAI is. This paper proposes a naturalistic model for evaluating both affective and cognitive characteristics of the CAI user. It begins with a discussion of features of user behavior, followed by a description of evaluation methodology that can lead to modeling user behavior. The paper concludes with a discussion of how implementation of this model can contribute to the fields of CAI and cognitive psychology.
Date: January 1, 1983
Creator: Stoddard, M.L.
Partner: UNT Libraries Government Documents Department

Cross-validation, learning set transformations, and generalization

Description: This paper discusses using cross-validation as an aid to generalization. It starts by showing how to use cross-validation to decide amongst a set of generalizer when the learning set consists of examples of the text-to-phoneme problem. In addition to reproducing the learning set perfectly, the generalizer so chosen by cross-validation has an error rate on the testing set (7%) close to that which NETtalk has on the learning set (5%). This paper then presents an example of using cross-validation as part of a front-end to generalizes, i.e., as part of an algorithm for pre-processing a learning set of input/output examples before trying to generalize from it. The results of thirty-six comparisons between the performance of a generalizer and the performance of the generalizer with this front-end are presented. These comparisons involve numerical, Boolean, and visual tasks. In all but one of the comparisons the front-end improves the generalization performance, often inducing perfect generalization. (The average ratio of the generalization error rate with the front-end to the generalization error rate without the front-end is 0.23, {plus minus} 0.05.) Finally, this paper ends by discussing some of the subtler mathematical issues involved in using cross-validation to help generalization. 7 refs., 3 figs.
Date: January 1, 1990
Creator: Wolpert, D.H.
Partner: UNT Libraries Government Documents Department

Two characterizations of sufficient matrices

Description: Two characterizations are given for the class of sufficient matrices defined by Cottle, Pang, and Venkateswaran. The first is a direct translation of the definition into linear programming terms. The second can be thought of as a generalization of a theorem of T. D. Parsons on P-matrices. 19 refs.
Date: December 1, 1990
Creator: Cottle, R.W. & Guu, Sy-Ming.
Partner: UNT Libraries Government Documents Department

Reflectional transformation for structural stiffness

Description: This paper presents a structural reflection-related transformation for structural stiffness. The stiffness transformation addresses reflection of a structure about any of the three coordinate planes and renders the desired stiffness matrix using a stiffness matrix for the same structure before reflection. This transformation is elegant and simple, provides an efficient and technically rigorous approach to derive the required stiffness matrix without structural remodeling, and can be readily programmed to quickly perform the required matrix manipulations. 2 figs.
Date: January 1, 1990
Creator: Vashi, K.M.
Partner: UNT Libraries Government Documents Department

Sensitivity-analysis techniques: self-teaching curriculum

Description: This self teaching curriculum on sensitivity analysis techniques consists of three parts: (1) Use of the Latin Hypercube Sampling Program (Iman, Davenport and Ziegler, Latin Hypercube Sampling (Program User's Guide), SAND79-1473, January 1980); (2) Use of the Stepwise Regression Program (Iman, et al., Stepwise Regression with PRESS and Rank Regression (Program User's Guide) SAND79-1472, January 1980); and (3) Application of the procedures to sensitivity and uncertainty analyses of the groundwater transport model MWFT/DVM (Campbell, Iman and Reeves, Risk Methodology for Geologic Disposal of Radioactive Waste - Transport Model Sensitivity Analysis; SAND80-0644, NUREG/CR-1377, June 1980: Campbell, Longsine, and Reeves, The Distributed Velocity Method of Solving the Convective-Dispersion Equation, SAND80-0717, NUREG/CR-1376, July 1980). This curriculum is one in a series developed by Sandia National Laboratories for transfer of the capability to use the technology developed under the NRC funded High Level Waste Methodology Development Program.
Date: June 1, 1982
Creator: Iman, R.L. & Conover, W.J.
Partner: UNT Libraries Government Documents Department

Improved selection in totally monotone arrays

Description: This paper's main result is an O(({radical}{bar m}lgm)(n lg n) + mlg n)-time algorithm for computing the kth smallest entry in each row of an m {times} n totally monotone array. (A two-dimensional A = a(i,j) is totally monotone if for all i{sub 1} < i{sub 2} and j{sub 1} < j{sup 2}, < a(i{sub 1},j{sub 2}) implies a(i{sub 2},j{sub 1})). For large values of k (in particular, for k=(n/2)), this algorithm is significantly faster than the O(k(m+n))-time algorithm for the same problem due to Kravets and Park. An immediate consequence of this result is an O(n{sup 3/2} lg{sup 2}n)-time algorithm for computing the kth nearest neighbor of each vertex of a convex n-gon. In addition to the main result, we also give an O(n lg m)-time algorithm for computing an approximate median in each row of an m {times} n totally monotone array; this approximate median is an entry whose rank in its row lies between (n/4) and (3n/4) {minus} 1. 20 refs., 3 figs.
Date: January 1, 1991
Creator: Mansour, Y. (Harvard Univ., Cambridge, MA (United States). Aiken Computation Lab.); Park, J.K. (Sandia National Labs., Albuquerque, NM (United States)); Schieber, B. (International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center) & Sen, S. (AT and T Bell Labs., Murray Hill, NJ (United States))
Partner: UNT Libraries Government Documents Department

Overview of the ANS (American Nuclear Society) mathematics and computation software standards

Description: The Mathematics and Computations Division of the American Nuclear Society sponsors the ANS-10 Standards Subcommittee. This subcommittee, which is part of the ANS Standards Committee, currently maintains four ANSI/ANS software standards. These standards are: Recommended Programming Practices to Facilitate the Portability of Scientific Computer Programs, ANS-10.2; Guidelines for the Documentation of Computer Software, ANS-10.3; Guidelines for the Verification and Validation of Scientific and Engineering Computer Programs for the Nuclear Industry, ANS-10.4; and Guidelines for Accommodating User Needs in Computer Program Development, ANS-10.5. 5 refs.
Date: January 1, 1991
Creator: Smetana, A.O.
Partner: UNT Libraries Government Documents Department

A dynamic menuing and security system

Description: Commonly, a system creator will seek to limit access to various parts of an information system based on the user is and what authorities should be granted that person. With a payroll system, it would be expected that only a limited number of people would be able to change data, a larger segment of managers would be able to view information on their particular department, and perhaps everyone would be able to see their own information. This sort of situation presents an interesting problem for the system designer who would like to minimize the amount of coding necessary to accomplish this level of flexibility and to simplify maintenance of the application system. We were presented with such a problem with a project accounting system. The two first implementations of this application system were based on simply locking users out of screens for which they had no authority. A polite message was displayed indicating that the user did not have authority to access the screen in question. This method had the potential of becoming a security problem because the code was replicated in each of fifteen menus. Changes had to propagated around several different menus for several different levels of authorization. This created difficulty for us in maintaining a consistent set of key strokes throughout the system. Exceptions had to be handled via replicated code. These problems led us to re-evaluate the existing system and to create a system based on the following set of user requirements: access to functions must be based on the user's level of authority; all menus should require the basic keystrokes; menus to which a user dose not have authority should not be displayed to that user; and finally, so-called super users'' must be able to access data from the point of view of various sub-organizations.
Date: January 1, 1992
Creator: Koon, D.M. & Zowin, J.A.
Partner: UNT Libraries Government Documents Department

Introduction to human factors

Description: Some background is given on the field of human factors. The nature of problems with current human/computer interfaces is discussed, some costs are identified, ideal attributes of graceful system interfaces are outlined, and some reasons are indicated why it's not easy to fix the problems. (LEW)
Date: March 1, 1988
Creator: Winters, J.M.
Partner: UNT Libraries Government Documents Department

Discrete Pearson distributions

Description: These distributions are generated by a first order recursive scheme which equates the ratio of successive probabilities to the ratio of two corresponding quadratics. The use of a linearized form of this model will produce equations in the unknowns matched by an appropriate set of moments (assumed to exist). Given the moments we may find valid solutions. These are two cases; (1) distributions defined on the non-negative integers (finite or infinite) and (2) distributions defined on negative integers as well. For (1), given the first four moments, it is possible to set this up as equations of finite or infinite degree in the probability of a zero occurrence, the sth component being a product of s ratios of linear forms in this probability in general. For (2) the equation for the zero probability is purely linear but may involve slowly converging series; here a particular case is the discrete normal. Regions of validity are being studied. 11 refs.
Date: November 1, 1991
Creator: Bowman, K.O. (Oak Ridge National Lab., TN (United States)); Shenton, L.R. (Georgia Univ., Athens, GA (United States)) & Kastenbaum, M.A. (Kastenbaum (M.A.), Basye, VA (United States))
Partner: UNT Libraries Government Documents Department