Digital Commons Network^™

Mpj: A Proposed Java Message Passing Api And Environment For High Performance Computing, Mark Baker, Bryan Carpenter

Northeast Parallel Architecture Center

In this paper we sketch out a proposed reference implementation for message passing in Java (MPJ), an MPI-like API from the Message-Passing Working Group of the Java Grande Forum [1,2]. The proposal relies heavily on RMI and Jini for finding computational resources, creating slave processes, and handling failures. User-level communication is implemented efficiently directly on top of Java sockets.

Lily-A Generator For Compiler Frontends, Thomas J. Sager

Computer Science Technical Reports

No abstract provided.

The Slicing Extent Technique For Fast Ray Tracing, Sudhanshu Kumar Semwal

Retrospective Theses and Dissertations

A new technique for image generation using ray tracing is introduced. The “Slicing Extent Technique” (SET) partitions object space with slicing planes perpendicular to all three axes. Planes are divided into two dimensional rectangular cells, which contain pointers to nearby objects. Cell size and the space between slices varies, and is determined by the objects’ locations and orientations. Unlike oct-tree and other space-partitioning methods, SET is not primarily concerned with dividing space into mutually exclusive volume elements (‘voxels’) and identifying objects within each voxel. Instead, SET is based on analysis of projections of objects onto slicing planes. In comparison to …

Design And Performance Analysis Of A Relational Replicated Database Systems, Jon Gregory Hanson

Retrospective Theses and Dissertations

The hardware organization and software structure of a new database system are presented. This system, the relational replicated database system (RRDS), is based on a set of replicated processors operating on a partitioned database. Performance improvements and capacity growth can be obtained by adding more processors to the configuration. Based on designing goals a set of hardware and software design questions were developed. The system then evolved according to a five-phase process, based on simulation and analysis, which addressed and resolved the design questions. Strategies and algorithms were developed for data access, data placement, and directory management for the hardware …

Lazy Evaluation And Nondeterminism Make Backus' Fp-Systems More Practical, Atanas Radenski

Mathematics, Physics, and Computer Science Faculty Articles and Research

Backus' FP-systems are made more practical by introducing into them lazy evaluation and nondeterminism. This is done in the framework of a concrete programming language called FP*. From the one hand, this language is almost as mathematical as FP-systems are. From the other hand, it gives the possibility to manage secondary memory and to develop such applications as, for instance, interactive and distributed file systems. Experimental versions of a compiler and an interpreter for the FP* language are implemented.

Decision Problems Resulting From Grammatical Inference, Sandor Horvath, Efim Kinber, Arto Salomaa, Sheng Yu

School of Computer Science & Engineering Faculty Publications

Grammatical inference is one of the classical areas of language theory.

Multilist And Inverted File System Performance Measurements, Ashok Chandramouli

Masters Theses

"This study evaluates the multilist and inverted file systems. It describes the structure of the two file system and then proceeds to investigate the performance. The performance is based on quantitative estimates of space requirements for file system, time to retrieve records, time to insert a record, time to delete a record, time to update a record and time to exhaustively read and reorganize the file system. The study then investigates specific situations in which one file system seems to perform better than the other"--Abstract, page ii.

Ethernet Performance: Design And Implementation Study, Michael M. Chaney

Masters Theses

"General concepts concerning local area network designs, functions and topologies will be presented. Ethernet as a multipoint bus topology local area network will be presented in detail. The Carrier Sense Multiple Access/Collision Detect (CSMA/CD) method of fairly regulating access to the shared network bus is studied. The Ethernet Network in relation to the Open Systems Interconnect (OSI) is reviewed, but only the layers pertaining to Ethernet are discussed throughout the majority of the paper. The specifications as described by Xerox, Digital and Intel are presented to help the designer understand the network's physical limitations. Analytical models are used to predict …

Lily: A Parser Generator For Ll(1) Languages, Timothy Topper Taylor

Masters Theses

This paper discusses the design and implementation of Lily, a language for generating LL(1) language parsers, originally designed by Dr. Thomas J. Sager of the University of Missouri--Rolla. A method for the automatic generation of parser tables is described which creates small, highly optimized tables, suitable for conversion to minimal perfect hash functions.

An implementation of Lily is discussed with attention to design goals, implementation of parser table generation, and table optimization techniques. Proposals are made detailing possibilities for further augmentation of the system. Examples of Lily programs are given as well as a manual for the system.

Performance Parameter Measurements Of Generic Files, Sankarraman Subramanian

Masters Theses

"This study discusses the performance parameter measurements of generic files, the pile file, the sequential file, the indexed-sequential file, the indexed file and the direct file. The file performance measurements are compiled in a software package. The study then describes the use of such software package as a simulation tool in a file design environment"--Abstract, page iii.

The Whittier College Bbs, Robert Hansen

Whittier Scholars Program

This senior project details the process of creating the Whittier College Bulletin Board System (BBS). The Whittier College BBS was intended to facilitate intelligent, aware, and concerned communication about important and current events. Within the project are sections for the Details of Operation, Summary, Technical Discussions of Problems with Code and Implementation, Statistics, Source Code Listing, and BBS Log. Appendix B is a hard copy sample of the Whittier College BBS.

Decoding Substitution Ciphers By Means Of Word Matching With Application To Ocr, George Nagy, Sharad C. Seth, Kent Einspahr

School of Computing: Faculty Publications

A substitution cipher consists of a block of natural language text where each letter of the alphabet has been replaced by a distinct symbol. As a problem in cryptography, the substitution cipher is of limited interest, but it has an important application in optical character recognition. Recent advances render it quite feasible to scan documents with a fairly complex layout and to classify (cluster) the printed characters into distinct groups according to their shape. However, given the immense variety of type styles and forms in current use, it is not possible to assign alphabetical identities to characters of arbitrary size …

Training For The Airland Battle With Modeling And Simulation On The Microcomputer, David Dean Holmes

Masters Theses

"This paper describes a methodology for modifying a combat training simulation model to include a comprehensive data structure and computer software, to allow the model to be implemented on a microcomputer. It begins by developing a topology for combat simulation models and proceeds to define a data structure suitable for describing military units and facilitating the varied aspects of the simulation. An eclectic approach to the development of the model and the implementing software is followed throughout. Appropriate aspects of a number of models are incorporated into a single model suitable for training military commanders and their staffs. PASCAL, a …

The Implementation Of A Compiler Targeted To A Multiprocessor Environment, R. Dwight Schettler

Masters Theses

"This research is an application of the techniques which have been developed for the detection and exploitation of implicit parallelism. A system has been developed based on Intel 86/12A single board computers utilizing dual-port RAM for communication. The compiler system accepts the source code of a simple block structured language and generates parallel programs to be executed on the Multibus system. The techniques used for detection of parallelism are stressed"--Abstract, page ii.

A Proposed C Language Binding For The Graphical Kernel System-3d, Mark Gerard Bolten

Masters Theses

"This thesis introduces a proposed C language binding definition for the International Standards Organization's draft international standard of the Graphical Kernel System-3D. This work augments the earlier C language binding of the two dimensional version of the Graphical Kernel System commonly known as GKS. The proposed function interface will provide a basis for, if not a final, C language binding for the three dimensional version of the Graphical Kernel System"--Abstract, page ii.

Medial Axis Transform Using Ridge Following, Richard Mark Volkmann

Masters Theses

"The intent of this investigation has been to find a robust algorithm for generation of the medial axis transform (MAT). The MAT is an invertible, object centered, shape representation defined as the collection of the centers of disks contained in the shape but not in any other such disk. Its uses include feature extraction, shape smoothing, and data compression. MAT generating algorithms include brushfire, Voronoi diagrams, and ridge following. An improved implementation of the ridge following algorithm is given. Orders of the MAT generating algorithms are compared. The effects of the number of edges in the polygonal approximation, shape area, …

A.R.M.S., Arbitrary Robot Modeling System, William Richard Gerlt

Masters Theses

“This paper deals with the mathematical modeling of robot arms. Modeling robot arms includes finding a suitable way to describe a robot, turning the description into a mathematical system, and using the system to find a set of equations which can be used to control the robot.

One of the problems associated with robot modeling is that it involves a great deal of mathematics. When the process is done by hand, the large volume of mathematics makes the process very time consuming and prone to errors. These problems are part of the motivation for automating the modeling of robots.

ARMS …

Intensional Reasoning About Knowledge, Oliver B. Popov

Doctoral Dissertations

"As demands and ambitions increase in Artificial Intelligence, the need for formal systems that facilitate a study and a simulation of a machine cognition has become an inevitability. This paper explores and developes the foundations of a formal system for propositional reasoning about knowledge. The semantics of every meaningful expression in the system is fully determined by its intension, the set of complexes in which the expression is confirmed. The knowledge system is based on three zeroth-order theories of epistemic reasoning for consciousness, knowledge and entailed knowledge. The results presented in the paper determine the soundness and the completeness of …

Impact Of Automation On Process Control Decision-Making, Steven M. Miller, Susan R. Bereiter

Research Collection School Of Computing and Information Systems

This paper investigates changes in the process control of a vehicle assembly plant which had been modernized from a principally manual procedure to one that uses programmable automation extensively. Process control is defined as the information flow and decision-making required to perform basic process operations. We investigate the effects of implementing a computer-integrated production system on the amount and types of process control decision-making and on the distribution of process control decision-making between humans and machines. After automation, the emphasis on decisions regarding product quality specifications increased and the emphasis on decisions related to flexibility in handling a variety of …

[Introduction To] A Gentle Introduction To The Vax System, John R. Hubbard

Bookshelf

This book was written originally for students enrolled in computer science courses at the University of Richmond. Very few had worked on a large time-sharing system like the VAX.

The purpose of this book is to help the novice become comfortable using any of the Digital Equipment Corporations VAX computers, from the Micro-VAX to the powerful VAX 8000 system. The book is meant to be used as a tutorial.

The Use Of Services In The Tilde Environment, Craig E. Wills

Department of Computer Science Technical Reports

No abstract provided.

Finding The Convex Hull Of A Sorted Point Set In Parallel, Michael T. Goodrich

Department of Computer Science Technical Reports

No abstract provided.

The Cypress Link Level Protocol, Douglas E. Comer

Department of Computer Science Technical Reports

No abstract provided.

The Cypress Network, Douglas E. Comer, Thomas Narten, Rajendra Yuavatkar

Department of Computer Science Technical Reports

No abstract provided.

The Cypress Coaxial Backbone Packet Switch, Douglas E. Comer, Thomas Narten, Rajendra Yuavatkar

Department of Computer Science Technical Reports

No abstract provided.

Some Explicit Formulas For Mixed Exponential Service Systems, Vernon J. Rego

Department of Computer Science Technical Reports

No abstract provided.

On The Analysis Of The Average Height Of A Digital Trie: Another Approach, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

Finding Maximum Cliques On Circular-Arc Graphs, Alberto Apostolico, Susanne E. Hambrusch

Department of Computer Science Technical Reports

No abstract provided.

Availability Driven Multiple Access Network Architecture, Dan Cristian Marinescu, Vernon J. Rego, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

Structural, Remote Sensing And Multivariate Correlation Methods As Aids To Mineral Exploration, Central Ireland, D.W. Coller, M.F. Critchley, J.M. Dolan, Ciaran Mcdonnell, C.J. Murphy, W.E.A. Phillips, D.J. Sanderson

Books/Book chapters

This work discusses structural, remote sensing and multivariate correlation methods as aids to mineral exploration in West Central Ireland. The work was performed as part of the EU-funded CREST project.