16442663
Parallel univariate polynomial factorization on shared-memory multiprocessors
Using parallelism afforded by shared-memory multiprocessors to speed up systems for polynomial factorization is discussed. The approach is to take the fastest known factoring algorithm for practical purposes and parallelize key parts of it. The univariate factoring algorithm consists of two major tasks (a) factoring modulo small integer primes and (b) EEZ lifting and recovery of true factors. A C coded system PFACTOR that implements (a) in parallel is described in detail. PFACTOR is a stand-alone parallel factorizer that can take input from a file, a pipe or a socket connection over a network. It can also be used interactively as a UNIX command. PFACTOR consists of parallel selection of primes, automatic balancing of work, parallel Berlekamp algorithm, and parallel reconciliation of degrees of factors modulo different primes. Actual timings on the Encore Multimax show the effectiveness of the approach. Work on part (b) is still on going.
18326845
Parallel univariate p-adic lifting on shared-memory multiprocessors
Parallelization of univariate p-aclic lifting, a procedure important in modem gcd and factorization algorithms, is presented. The strategy is to take the fastest known sequential algorithm and parallelize its key steps: lift basis, residue, correction coefficients, updating factors, cldecting true factors, and reformulation for continued lifting. Both linear and quadratic lifting are investigated. A new procedure for reformulating the lifting after finding true factors speeds up the sequential and the parallel lifting. PLIFT, a software package written in C for a 26-processor Sequent Balance, implements the parallel algorithms. Timing results are given in an appendix,
28403175
GI/S: A Graphical User Interface For Symbolic Computation Systems
The design and implementation of GI/S, a Graphical user Interface for Symbolic computation systems, is described. The system provides a multiple window environment for the high-resolution 2-D display of mathematical expressions, the ability to select and manipulate parts of expressions with a mouse, and graphics plotting of mathematical expressions. GI/S also provides command line editing and a history mechanism for editing and re-executing past commands. GI/S is written in Franz Lisp for the Macsyma system and has been implemented on the Tektronix 4404 workstation.
10322452
SUI: a system independent user interface for an integrated scientific computing environment
The design and implementation of a Scientific User Interface is presented. Written in the C language, SUI is a window-menu-mouse oriented graphical user interface that is designed to provide a modern and integrated computing environment for scientific work. SUI can serve multiple client systems in parallel including symbolic, numeric, graphics and document formatting systems. SUI achieves hardware and operating system independence as well as network transparency by employing the X11 protocols and achieves client system independence by defining a client-SUI protocol that is simple and effective. Features of SUI includes input editing, history, 2-D mathematical expression display, interactive selection of subexpressions, interactive display and manipulation of 2-D and 3-D plots of mathematical functions, cut and paste with syntax translation, command templates, incremental 2-D display of mathematical input, and interactive configuration. A prototype system demonstration is planned for ISSAC'90
6086436
3D Line Image Analysis - A Heuristic Parallel Approach with Learning and Recognition
Abstract A heuristic parallel approach for (3d) line image analysis is introduced by using the concept of coordinated graph, layered graph representation, and parallel matching techniques and it significantly reduces the time required for dealing with three-dimensional line image analysis problems. Their fundamental properties and the concept of finite representations are investigated, and an interactive and iterative recognition algorithm with learning and recognition as a part of each other is presented. Several interested examples including curved and disconnected line images are illustrated. In addition to its importance in theoretical studies, this approach can also be applied to 3d object recognition, image processing, and computer vision in industrial, military, and medical fields.
207116582
A Thinning Algorithm Based on the Force Between Charged Particles
A new thinning algorithm based on the well known concept of the force of attraction or repulsion between charged particles is presented. This algorithm generates connected skeletons which preserve the shape and end-points of the original patterns. Its performance is experimentally compared with four other known algorithms published in the literature. For the sake of comparison, a reasoned set of test data is introduced. The results of our comparison reveal that the proposed CPM (Charge Particle Method) algorithm is almost as fast as the fastest of those compared. For thin images obtainable from low resolution scanners or coarse scanned images, the CPM algorithm is the fastest.
31996759
Analysis and Design of Parallel Thinning Algorithms - A Generic Approach
In this paper, a generic approach for the analysis and design of parallel thinning algorithms is presented. The procedures for designing 4-subcycle/iteration, 2-subcycle/iteration, and 1-subcycle/iteration thinning algorithms are developed. The experimental results show that these thinning algorithms designed by proposed approach preserve image connectivity, produce thinner results, and obtain faster speed than many existing key thinning algorithms. As an example, a 1-subcycle/iteration algorithm and its experimental results were illustrated, which is in general about two times faster than others in the literature.
2060430
A Defect in Dempster-Shafer Theory
By analyzing the relationships among chance, weight of evidence and degree of belief, we show that the assertion "probability functions are special cases of belief functions" and the assertion "Dempster's rule can be used to combine belief functions based on distinct bodies of evidence" together lead to an inconsistency in Dempster-Shafer theory. To solve this problem, we must reject some fundamental postulates of the theory. We introduce a new approach for uncertainty management that shares many intuitive ideas with D-S theory, while avoiding this problem.
5826256
Confidence as Higher-Order Uncertainty
With conflicting evidence, a reasoning system derives uncertain conclusions. If the system is open to new evidence, it faces additionally a higher-order uncertainty, because the first-order uncertainty evaluations are uncertain themselves — they can be changed by future evidence. A new measurement, confidence, is introduced for this higher-order uncertainty. It is defined in terms of the amount of available evidence, and interpreted and processed as the relative stability of the first-order uncertainty evaluation. Its relation with other approaches of “reasoning with uncertainty” is also discussed.