17343502
IAMC architecture and prototyping: a progress report
Internet Accessible Mathematical Computation (IAMC) is a distributed framework to supply mathematical computing powers over the Internet. Presented are conceptual and experimental work on the IAMC architecture, a client prototype (Dragonfly), client GUI, a server prototype (Starfish), the Mathematical Computation Protocol (MCP), mathematical data encoding, and the external compute engine interface.
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.
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
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.
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.
2424601
Users' interaction with World Wide Web resources: an exploratory study using a holistic approach
Abstract This paper presents the first part of the research on user–Web interaction: a multidimensional model, methodology, and general findings. The objectives of this study are three-fold: (1) to explore factors of user–Web interaction in finding factual information and what happens during this interaction; (2) to develop a conceptual framework for studying user–Web interaction; and (3) to apply a process-tracing method for conducting holistic user–Web studies. The proposed model consists of three components: user, interface, and the World Wide Web. User–Web interaction is viewed as a communication process facilitated through an interface. A process-tracing technique has been designed to capture the processes of user-Web interactions. Twenty-four graduate students participated in this study. Prior to the interaction, each participant was given a questionnaire to report his/her computer and Web experience, the State Trait Anxiety Inventory (form Y1 and form Y2) to measure affective states, and an individually administered Embedded Figure Test to measure cognitive style. Each participant used the Web to find answers to two factual questions. Both the processes (continuous screen shots) and the concurrent verbalizations of thoughts were recorded in synchronized video–audio data. The findings provided rich information on users’ cognitive, affective and physical behaviors. The proposed model is used to present the findings of user behavior in connections with interfaces and the Web.
26841509
From inheritance relation to nonaxiomatic logic
Abstract A nonaxiomatic reasoning system is an adaptive system that works with insufficient knowledge and resources. At the beginning of the paper, three binary term logics are defined. The first is based only on an inheritance relation. The second and the third suggest a novel way to process extension and intension, and they also have interesting relations with Aristotle's syllogistic logic. Based on the three simple systems, a nonaxiomatic logic is defined. It has a term-oriented language and an experience-grounded semantics. It can uniformly represent and process randomness, fuzziness, and ignorance. It can also uniformly carry out deduction, abduction, induction, and revision.
17905930
Evaluating Team Performance at the Edge of Chaos
We introduce a concise approach to teamwork evaluation on multiple levels – dealing with agent’s behaviour spread and multi-agent coordination potential, and abstracting away the team decision process. The presented quantitative information-theoretic methods measure behavioural and epistemic entropy, and detect phase transitions – the edge of chaos – in team performance. The techniques clearly identify under-performing states, where a change in tactics may be warranted. This approach is a step towards a unified quantitative framework on behavioural and belief dynamics in complex multi-agent systems.
17919993
A Note on the Edge-Connectivity of Cages
A (k; g)-graph is a k-regular graph with girth g. A (k; g)-cage is a (k; g)-graph with the smallest possible number of vertices. In this paper we prove that (k; g)cages are k-edge-connected if k ≥ 3 and g is odd.