Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Computer Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 56041 - 56070 of 57980

Full-Text Articles in Physical Sciences and Mathematics

The N-Body Pipeline, Per Brinch Hansen Mar 1991

The N-Body Pipeline, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

A general pipeline for all-pairs computations is adapted for direct force summation of n bodies which interact through gravitation only. To achieve approximate load balance the pipeline is folded several times across an array of processors. The performance of the pipeline is analyzed and measured on a Computing Surface.


A Unified Framework For Three-Valued Semantical Treatments Of Logic Programming, Feng Yang Mar 1991

A Unified Framework For Three-Valued Semantical Treatments Of Logic Programming, Feng Yang

Electrical Engineering and Computer Science - Technical Reports

Based on Fiting's Φ operator a unified framework for three-valued semantics of logic programming is presented. The truth space used in the framework is the class of partial interpretations. Underlying the truth space is two partial orderings, knowledge ordering and truth ordering. It turns out that the truth space with the truth ordering is a complete lattice and the truth space with knowledge ordering is a semi-complete lattice. Φ is proved to be continuous over the complete lattice and monotonic over the semi-complete lattice. With the use of Φ operator two well-known three-valued semantics for logic programming, Fitting's three-valued semantics …


Duality In Logic Programming, Feng Yang Mar 1991

Duality In Logic Programming, Feng Yang

Electrical Engineering and Computer Science - Technical Reports

Various approximations of classic negation have been proposed for logic programming. But the semantics for those approximations are not entirely clear. In this paper a proof-theoretic operator, we call it failure operator, denoted as FP, is associated with each logic program to characterize the meaning of various negations in logic programming. It is shown that the failure operator FP is a dual of the TP, immediate consequence operator developed by Van Emden and Kowalski and is downward continuous. It has the desirable properties entirely analogous to what TP has such as continuity, having a unique least fixpoint and a unique …


A Study Of Approximating The Moments Of The Job Completion Time In Pert Networks, Kishan Mehrotra, John Chai, Sharma Pillutla Mar 1991

A Study Of Approximating The Moments Of The Job Completion Time In Pert Networks, Kishan Mehrotra, John Chai, Sharma Pillutla

Electrical Engineering and Computer Science - Technical Reports

The importance of proper management of projects has not gone unrecognized in industry and academia. Consequently tools like Critical Path Method (CPM) and Program Evaluation Review Technique (PERT) for project planning have been the focus of attention of both practitioners and researchers. Determination of the Time to Complete the Job (TCJ) in PERT networks is important for planning and bidding purposes. The complexity involved in accurately determining the TCJ has led to the development of many approximating procedures. Most of them ignore the dependence between paths in the network. We propose an approximation to determine the TCJ which explicitly recognizes …


Dna Mapping Algorithms: Topological Mapping, Kenneth Moorman, Paul Poulosky, Will Gillett Mar 1991

Dna Mapping Algorithms: Topological Mapping, Kenneth Moorman, Paul Poulosky, Will Gillett

All Computer Science and Engineering Research

There are several basic approaches that can be used in attempting to produce high-resolution DNA restriction maps. A standard approach is the match/merge approach in which first the topology of the map units being mapped together is suppressed and lists of potential matches between fragments are generated, and second the topology is introduced to eliminate matchlists which are inconsistent with the topology. This technical report documents a different approach to DNA mapping, known as topological mapping. In topological mapping the precedence of the two criteria are reversed, i.e., the topology of the two map units is used as the primary …


Eliminating Extraneous Solutions In Curve And Surface Operations, Christoph M. Hoffmann, Pamela J. Vermeer Feb 1991

Eliminating Extraneous Solutions In Curve And Surface Operations, Christoph M. Hoffmann, Pamela J. Vermeer

Department of Computer Science Technical Reports

No abstract provided.


A Framework For 1-D Compaction With Forbidden Region Avoidance, Susanne E. Hambrusch, Hung-Yi Tu Feb 1991

A Framework For 1-D Compaction With Forbidden Region Avoidance, Susanne E. Hambrusch, Hung-Yi Tu

Department of Computer Science Technical Reports

No abstract provided.


Analyzing Availability Of Replicated Database Systems, Bharat Bhargava, Abdelsalam Helal, Karl Friesen Feb 1991

Analyzing Availability Of Replicated Database Systems, Bharat Bhargava, Abdelsalam Helal, Karl Friesen

Department of Computer Science Technical Reports

No abstract provided.


Multisearch Techniques: Parallel Data Structures On Mesh-Connected Computers, Mikhail J. Atallah, Frank Dehne, Russ Miller, Andrew Rau-Chaplin, Jyh-Jong Tsay Feb 1991

Multisearch Techniques: Parallel Data Structures On Mesh-Connected Computers, Mikhail J. Atallah, Frank Dehne, Russ Miller, Andrew Rau-Chaplin, Jyh-Jong Tsay

Department of Computer Science Technical Reports

No abstract provided.


A Robust Intersection Algorithm Based On Delaunay Triangulation, Kokichi Sugihara Feb 1991

A Robust Intersection Algorithm Based On Delaunay Triangulation, Kokichi Sugihara

Department of Computer Science Technical Reports

No abstract provided.


Autocorrelation On Words And Its Applications, Philippe Jacquet, Wojciech Szpankowski Feb 1991

Autocorrelation On Words And Its Applications, Philippe Jacquet, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.


Efficient Crcw-Pram Algorithms Combining Multiple Autonomous Databases, Alberto Apostolico Feb 1991

Efficient Crcw-Pram Algorithms Combining Multiple Autonomous Databases, Alberto Apostolico

Department of Computer Science Technical Reports

No abstract provided.


An Optimal Parallel Algorithm For Detecting Weak Visibility Of A Simple Polygon, Danny Z. Chen Feb 1991

An Optimal Parallel Algorithm For Detecting Weak Visibility Of A Simple Polygon, Danny Z. Chen

Department of Computer Science Technical Reports

No abstract provided.


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, February 1991, College Of Engineering And Computer Science, Wright State University Feb 1991

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, February 1991, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


A Practical Hierarchial Model Of Parallel Computation: The Model, Todd Heywood, Sanjay Ranka Feb 1991

A Practical Hierarchial Model Of Parallel Computation: The Model, Todd Heywood, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

We introduce a model of parallel computation that retains the ideal properties of the PRAM by using it as a sub-model, while simultaneously being more reflective of realistic parallel architectures by accounting for and providing abstract control over communication and synchronization costs. The Hierarchical PRAM (H-PRAM) model controls conceptual complexity in the face of asynchrony in two ways. First, by providing the simplifying assumption of synchronization to the design of algorithms, but allowing the algorithms to work asynchronously with each other; and organizing this "control asynchrony" via an implicit hierarchy relation. Second, by allowing the restriction of "communication asynchrony" in …


Saam: The Strategic Asset Allocation Model, Judy Lewis, Todd Gamble, John Tai Feb 1991

Saam: The Strategic Asset Allocation Model, Judy Lewis, Todd Gamble, John Tai

All Computer Science and Engineering Research

Asset Allocation has become a dominant factor for investment strategies in recent years. It has found that by holding a strategically diversified portfolio, a high total return on investments can be maintained while, at the same time, reducing portfolio volatility. With recent federal regulations mandating pension investment responsibilities, appropriate asset allocation has become more important than ever. SAAM is a software package specifically designed to be used as a tool to aid the investment professional in determining pension portfolio allocations. SAAM uses the expect system shell CLIPS, has a user-friendly interface, displays output graphically, and runs within the confines of …


Performance Analysis Of The Ethernet Under Conditions Of Bursty Traffic, Tony Y. Mazraani, Gurudatta M. Parulkar Feb 1991

Performance Analysis Of The Ethernet Under Conditions Of Bursty Traffic, Tony Y. Mazraani, Gurudatta M. Parulkar

All Computer Science and Engineering Research

In this paper we present a simulation study of the Ethernet performance under conditions of bursty traffic. This study is motivated by two observations: Ethernet will continue to be a widely used Local Area Network (LAN), especially as an access LAN for future high speed internet (or Broadband ISDN); and future high speed applications can best be modeled as bursty sources. Bursty traffic in this study is specified using three parameters: peak bandwidth, average bandwidth, and burst factor. The simulation study shows that the inherent behavior of the Ethernet does not change with bursty traffic. That is, as long as …


Concurrency Control, Version Management And Transactions In Advanced Database Systems, Jonathan Walpole, Muntuck Yap Feb 1991

Concurrency Control, Version Management And Transactions In Advanced Database Systems, Jonathan Walpole, Muntuck Yap

Computer Science Faculty Publications and Presentations

This document constitutes the final deliverable for the research project titled “An Investigation of Selected Issues in Transaction Mechanism Design for Object Oriented Databases.” The document describes our ideas for extending the traditional transaction concept for use in object oriented databases, and concentrates specifically on providing an underlying model to support the concurrency control and version management aspects of the problem. The ideas presented here are not however restricted to the domain of object oriented databases. They are more generally applicable to database systems that require flexibility in their versioning and concurrency control policies.

In this document we define a …


Performance Evaluation Of A Traffic Control Mechanism For Atm Networks, Andreas D. Bovopoulos Feb 1991

Performance Evaluation Of A Traffic Control Mechanism For Atm Networks, Andreas D. Bovopoulos

All Computer Science and Engineering Research

Future ATM networks will be required to support a plethora of services, transaction types and cell sequence behaviors with performance guarantees. Before this goal can be realized, however, some basically problems related to bandwidth allocation and traffic control in the ATM layer must be resolve. Such problems will in all likelihood defy solution as long as they studied in isolation without a unifying traffic characterization and traffic control framework. This work presented in this paper is part of an ongoing effort directed at the development of an integrated traffic characterization and control infrastructure for ATM networks. In this paper a …


Multiple Expert System, Umesh Kumar Mittal Jan 1991

Multiple Expert System, Umesh Kumar Mittal

Theses

In many domains, for example medical diagnosis, there are several sources of knowledge, e.g., several domain experts. These domain experts may have disagreements over some issues in the domain. Research in the area of human decision making suggests that a human decision is not always made based on the advice of a single expert. Many current expert systems, however, expect consistency in their knowledge bases. An expert system does not deliberate by reasoning that "on one hand..." but "on the other hand..." The knowledge engineer, who is not necessarily an expert in the same domain, ensures consistency by eliminating all …


Evolution Of A Communication System For Distributed Transaction Processing In Raid, Bharat Bhargava, Yongguang Zhang, Enrique Mafla Jan 1991

Evolution Of A Communication System For Distributed Transaction Processing In Raid, Bharat Bhargava, Yongguang Zhang, Enrique Mafla

Department of Computer Science Technical Reports

No abstract provided.


Mechanical Parts Orienting: The Case Of A Polyhedron On A Table, Michael Erdmann, Matthew T. Mason, George Vanĕček Jan 1991

Mechanical Parts Orienting: The Case Of A Polyhedron On A Table, Michael Erdmann, Matthew T. Mason, George Vanĕček

Department of Computer Science Technical Reports

No abstract provided.


Scheduling Support For An Internetwork Of Heterogeneous, Autonomous Processors, Steve Chapin, Eugene H. Spafford Jan 1991

Scheduling Support For An Internetwork Of Heterogeneous, Autonomous Processors, Steve Chapin, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


Experiments In Concurrent Stochastic Simulation: The Eclipse Paradigm, Vernon J. Rego, V. S. Sunderam Jan 1991

Experiments In Concurrent Stochastic Simulation: The Eclipse Paradigm, Vernon J. Rego, V. S. Sunderam

Department of Computer Science Technical Reports

No abstract provided.


The Parallelization Of Level 2 And 3 Blas Operations On Distributed Memory Machines, M. Aboelaze, N. P. Chrisochoides, Elias N. Houstis, C. E. Houstis Jan 1991

The Parallelization Of Level 2 And 3 Blas Operations On Distributed Memory Machines, M. Aboelaze, N. P. Chrisochoides, Elias N. Houstis, C. E. Houstis

Department of Computer Science Technical Reports

No abstract provided.


Asymptotic Properties Of Data Compressions And Suffix Trees, Wojciech Szpankowski Jan 1991

Asymptotic Properties Of Data Compressions And Suffix Trees, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.


Performance Of Pde Sparse Solvers On Hypercubes, Mo Mu, John R. Rice Jan 1991

Performance Of Pde Sparse Solvers On Hypercubes, Mo Mu, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.


A Spatial Index For Convex Simplicial Complexes In D Dimensions, George Vanĕček, Vincenzo Ferrucci Jan 1991

A Spatial Index For Convex Simplicial Complexes In D Dimensions, George Vanĕček, Vincenzo Ferrucci

Department of Computer Science Technical Reports

No abstract provided.


Gender Roles And Home Computer Use By Children, Trelles Whitfield D'Alemberte Jan 1991

Gender Roles And Home Computer Use By Children, Trelles Whitfield D'Alemberte

Dissertations, Theses, and Masters Projects

No abstract provided.


Parallel Test Pattern Generation Using Boolean Satisfiability, V. Sivaramakrishnan, Sharad C. Seth, Prathima Agrawal Jan 1991

Parallel Test Pattern Generation Using Boolean Satisfiability, V. Sivaramakrishnan, Sharad C. Seth, Prathima Agrawal

CSE Conference and Workshop Papers

Recently, Larrabee proposed a sequential test generation algorithm for combinational circuits based on boolean satisfiability and presented results on benchmark circuits in support of the viability of this approach. Parallel implementations of test generation algorithms are attractive in view of the known difficulty (NP-completeness) of the problem. In this paper we suggest parallel versions of Larrabee’s algorithm, suitable for implementation on shared-memory and message-passing multicomputers.