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A Comparison Of Text And Graphics As Effective User Interfaces In A Proposed Advanced Train Control System, Kenneth A. Organes Jan 1992

A Comparison Of Text And Graphics As Effective User Interfaces In A Proposed Advanced Train Control System, Kenneth A. Organes

UNF Graduate Theses and Dissertations

This study tested the effectiveness of three screen interface formats for use in a proposed on-board computer to be used as part of an advanced train control system. One of the three formats contained only graphic depictions of the data, one contained only textual representations and the third had a mixture of graphic and textual data.

Twenty-eight subjects with varying railroad experience were recruited for the experiment. They were divided into three groups, each of which was presented with a simulation using one of the three interface types. The simulations depicted possible engine, track and train conditions that might be …


Towards The Integration Of Object-Oriented Constructs Within Structured Query Language (Sql), Paul Francis Rabuck Jan 1992

Towards The Integration Of Object-Oriented Constructs Within Structured Query Language (Sql), Paul Francis Rabuck

UNF Graduate Theses and Dissertations

This paper explores the possibility of coupling SQL with a semantic data model. For this study, the primary objective was to build a working prototype of a program that allows a database designer to define data objects and their respective interrelationships using the Object-oriented Semantic Association Model (OSAM*).

The prototype isolates from the designer the low level commands (i.e., CREATE TABLE, CREATE INDEX) which comprise the SQL data definition language (DOL). Once the objects are defined by the designer, the prototype generates the relational database table definitions without the designer having to directly use the SQL DOL.


The Morphology Of Convex Polygons, Stephan Olariu Jan 1992

The Morphology Of Convex Polygons, Stephan Olariu

Computer Science Faculty Publications

A simple polygon P is said to be unimodal if for every vertex of P, the Euclidian distance function to the other vertices of P is unimodal. The study of unimodal polygons has emerged as a fruitful area of computational and discrete geometry. We study unimodality properties of a number of special convex polygons from the morphological point of view. In particular, we establish a hierarchy among three classes of convex polygons in terms of their unimodality properties.


A Tree Representation For P4-Sparse Graphs, B. Jamison, Stephan Olariu Jan 1992

A Tree Representation For P4-Sparse Graphs, B. Jamison, Stephan Olariu

Computer Science Faculty Publications

A graph G is P4-sparse if no set of five vertices in G induces more than one chordless path of length three. P4-sparse graphs generalize both the class of cographs and the class of P4-reducible graphs. We give several characterizations for P4-sparse graphs and show that they can be constructed from single-vertex graphs by a finite sequence of operations. Our characterization implies that the P4-sparse graphs admit a tree representation unique up to isomorphism. Furthermore, this tree representation can be obtained in polynomial time.


An Investigation Of Ibm Pc Computer Viruses Infection Rates And Types In A Western Australian Environment, Boon Guan Lee Jan 1992

An Investigation Of Ibm Pc Computer Viruses Infection Rates And Types In A Western Australian Environment, Boon Guan Lee

Theses : Honours

In recent years computer viruses have become increasingly significant as a form of computer abuse. By virtue of their reproductive capability, computer viruses can have cumulative and potentially catastrophic effects to the many people who use those affected computers. There is a growing concern in the computing community about these forms of electronic vandalism. This concern arises from the possible damage to stored information on which the work depends and the ensuing disruption of the work-place. Although the vandalism or purposeful abuse by introducing computer viruses to computer systems was originally mainly an American experience, research reports published by the …


Application Of Expert System Techniques For Award Implementation, Seng-Choon Yeoh Jan 1992

Application Of Expert System Techniques For Award Implementation, Seng-Choon Yeoh

Theses : Honours

This paper describes a pilot expert system project, PESWEA, developed in conjunction with The Western Australian Government Railways Commission (Westrail), to locate and implement an expert system pilot solution to the problems and complexities of the awards. The paper will outline the process used to develop and implement a solution to a business requirement. In particular, the methodologies for the project, shell selection, and knowledge acquisition will be presented and discussed. The fundamentals of expert systems will be discussed to provide the reader an insight into the technology. In addition, this paper reviews the literature relevant to the research questions. …


[Introduction To] The Vax Book: An Introduction, John R. Hubbard Jan 1992

[Introduction To] The Vax Book: An Introduction, John R. Hubbard

Bookshelf

This book is an expansion of the book, A Gentle Introduction to the Vax System. The purpose of the book is to guide the novice, step-by-step, through the initial stages of learning to use the Digital Equipment Corporation's Vax computers, running under the VMS operating system (Version 5.0 or later). As a tutorial for beginners, this book assumes no previous experience with computers.


Porting Chorus To The Pa-Risc: Booting, Jon Inouye, Ravi Konuru, Jonathan Walpole, Marion Hakanson Jan 1992

Porting Chorus To The Pa-Risc: Booting, Jon Inouye, Ravi Konuru, Jonathan Walpole, Marion Hakanson

Computer Science Faculty Publications and Presentations

We started out with the low level Tut (HP-CX 2.0) boot code. One of our goals was to reuse as much of this code as possible, which would reduce the amount of low level code we would have to debug. This was very important, especially fiince the RP 9000/834 has a very complex I/O architecture and we lacked any sophisticated debugging tools. Writing the PA-Chorus boot code involved modifying the Tut code to match the Chorus startup sequence. In the remainder of this section, we present an overview of the PA-RISC boot mechanisms and the Chorus startup sequence. Sectlon 2 …


Porting Chorus To The Pa-Risc: Building, Debugging, Testing And Validation, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole Jan 1992

Porting Chorus To The Pa-Risc: Building, Debugging, Testing And Validation, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This document is part of a series of reports describing the design decisions made in porting the Chorus Operating System to the Hewlett-Packard 9000 Series 800 workstation. This document describes the environment for building the Chorus kernel, the various kernel tests, and the debugging environment used for porting the Chorus operating system to the HP PA-RISC.

The information contained in this paper will be of interest to people who wish to:

• Use the PA-Chorus kernel for development and/or modification, • Know about the build environment for Chorus kernel on PA-RISC, • Know about the PA-Chorus approach to debugging, • …


Porting Chorus To The Pa-Risc: Overall Evaluation, Jonathan Walpole, Marion Hakanson, Jon Inouye, Ravi Konuru Jan 1992

Porting Chorus To The Pa-Risc: Overall Evaluation, Jonathan Walpole, Marion Hakanson, Jon Inouye, Ravi Konuru

Computer Science Faculty Publications and Presentations

This document is part of a series of reports describing the design decisions made in porting the Chorus Operating System kernel to the Hewlett-Packard 9000 Series 800 workstation. This document summarizes the matches and mis-matches between Chorus and the PA-RISC and outlines the general lessons learned during the project.

This document is intended for people who are interested in (a) the separation of machinedependent micro-kernel code from machine-independent micro-kernel code, (b) the interaction between operating system design and the PA-RISC architecture, and (c) the portability ofthe Chorus operating system.

The first report in the series, Porting Chorus to the PA-RISe: …


Porting Chorus To The Pa-Risc: Virtual Memory Manager, Jon Inouye, Marion Hakanson, Ravi Konuru, Jonathan Walpole Jan 1992

Porting Chorus To The Pa-Risc: Virtual Memory Manager, Jon Inouye, Marion Hakanson, Ravi Konuru, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This document describes the port ofthe Chorus virtual memory manager to the Hewlett-Packard Precision Architecture rusc (PA-RISC) workstation. The information contained in this paper will be of interest to people who:

• intend to port the Chorus virtual memory section. • intend to port a virtual memory design to the Hewlett-Packard PA-RISC.

The reader is strongly encouraged to read the following PA-Chorus documents before reading this document:

• Technical Report CSE-92-3, Porting Chorus to the PA-RISC: Project Overview


Porting The Chorus Supervisor And Related Low-Level Functions To The Pa-Risc, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole Jan 1992

Porting The Chorus Supervisor And Related Low-Level Functions To The Pa-Risc, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This document is part of a series of reports describing the design decisions made in porting the Chorus Operating System to the Hewlett-Packard 9000 Series 800 workstation.

The Supervisor is the name given by Chorus to a collection of low-level functions that are machine dependent and have to be implemented when Chorus is ported from one machine to another. The Supervisor is responsible for interrupt, trap and exception handling, managing low-level thread initialization, context switch, kernel initialization, managing simple devices (timer and console) and offering a low-level debugger. This document describes the port of the Supervisor and related low-level functions. …


Bounds On Constraint Weight Parameters Of Hopfield Networks For Stability Of Optimization Problem Solutions, Gursel Serpen Jan 1992

Bounds On Constraint Weight Parameters Of Hopfield Networks For Stability Of Optimization Problem Solutions, Gursel Serpen

Electrical & Computer Engineering Theses & Dissertations

The purpose of the presented research is to study the convergence characteristics of Hopfield network dynamics. The relation between constraint weight parameter values and the stability of solutions of constraint satisfaction and optimization problems mapped to Hopfield networks is investigated. A theoretical development relating constraint weight parameter values to solution stability is presented. The dependency of solution stability on constraint weight parameter values is shown employing an abstract optimization problem. A theorem defining bounds on the constraint weight parameter magnitudes for solution stability of constraint satisfaction and optimization problems is proved. Simulation analysis on a set of optimization and constraint …


Dynatapp Dynamic Timing Analysis With Partial Path Activation In Sequential Circuits, Prathima Agrawal, Vishwani Agrawal, Sharad C. Seth Jan 1992

Dynatapp Dynamic Timing Analysis With Partial Path Activation In Sequential Circuits, Prathima Agrawal, Vishwani Agrawal, Sharad C. Seth

School of Computing: Conference and Workshop Papers

This paper gives a method of finding all sensitizable paths in a non-scan synchronous sequential circuit. Path activation conditions of the circuit are mapped onto a single stuck type fault by adding a few modeling gates to the netlist. Only if the corresponding stuck type fault is found detectable by a sequential circuit test generator is the path considered sensitizable. A depth-first analysis of circuit topology, that determines all paths between primary inputs, primary outputs and flip-flops, employs a partial path hierarchy. Thus, all paths with a common unsensitizable segment need not be examined separately. Results on benchmark circuits show …


A Switch-Level Test Generation System, Kent L. Einspahr, Sharad C. Seth Jan 1992

A Switch-Level Test Generation System, Kent L. Einspahr, Sharad C. Seth

School of Computing: Conference and Workshop Papers

This paper presents a switch-level test generation system for synchronous sequential circuits in which a new algorithm for switch-level test generation and an existing fault simulator are integrated. For test generation, a switch-level circuit is modeled as a logic network that correctly models all aspects of switch-level behavior. The time-frame based algorithm uses asynchronous processing within each clock phase to achieve stability in the circuit, and synchronous processing between clock phases to model the passage of time. Unlike earlier time-frame based test generators for general sequential circuits, the test generator presented uses the monotonicity of the logic network to speed …


Porting Chorus To The Pa-Risc: Project Overview, Jonathan Walpole, Marion Hakanson, Jon Inouye, Ravi Konuru Jan 1992

Porting Chorus To The Pa-Risc: Project Overview, Jonathan Walpole, Marion Hakanson, Jon Inouye, Ravi Konuru

Computer Science Faculty Publications and Presentations

This document is part of a series of reports describing the design decisions made in porting the Chorus Operating System to the Hewlett-Packard 9000 Series 800 workstation. This document presents an overview of the project, and outlines the other reports in the series and the relationships between them.


Experimentation With Proof Methods For Non-Horn Sets, Christopher J. Merz, Ralph W. Wilkerson Jan 1992

Experimentation With Proof Methods For Non-Horn Sets, Christopher J. Merz, Ralph W. Wilkerson

Computer Science Faculty Research & Creative Works

Two Resolution Proof Strategies Developed by Peterson Are Implemented by Modifying Otter, an Existing Automated Theorem Prover. the Methods, Lock-T Refutation and LNL-T Refutation, Are Generalizations of Unit Refutation and Input Resolution, Respectively, to Non-Horn Sets and Represent Independent, Equivalent but Opposite Ways of Searching. the Algorithms Used Are based on a Corrected Version of the Foundational Work. the Strategies Have Been Tested on Various Non-Horn Challenge Problems from the Tarskian Geometry and the Non-Obvious Problem, with the Results Being in Some Cases Quite Favorable When Compared to Other Resolution Techniques.


Composite Stock Cutting Through Simulated Annealing, Hanan Lutfiyya, Bruce M. Mcmillin, Pipatpong Poshyanonda, Cihan H. Dagli Jan 1992

Composite Stock Cutting Through Simulated Annealing, Hanan Lutfiyya, Bruce M. Mcmillin, Pipatpong Poshyanonda, Cihan H. Dagli

Computer Science Faculty Research & Creative Works

This paper explores the use of Simulated Annealing as an optimization technique for the problem of Composite Material Stock Cutting. The shapes are not constrained to be convex polygons or even regular shapes. However, due to the composite nature of the material, the orientation of the shapes on the stock is restricted. For placements of various shapes, we show how to determine a cost function, annealing parameters and performance. © 1992.


Fault-Tolerant Concurrent Branch And Bound Algorithms Derived From Program Verification, Hanan Lutfiyya, Aggie Sun, Bruce M. Mcmillin Jan 1992

Fault-Tolerant Concurrent Branch And Bound Algorithms Derived From Program Verification, Hanan Lutfiyya, Aggie Sun, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

An important aspect which is often overlooked in software design of distributed environments is that of fault tolerance. Many methodologies in the past have attempted to provide fault tolerance efficiently but have never been successful at eliminating explicit time and space redundancy. One approach for providing fault tolerance is through examining the behavior and properties of the application and deriving executable assertions that detect faults. Our work focuses on transforming the assertions of a verification proof of a program to executable assertions. These executable assertions may be embedded in the program to create a fault-tolerant program. It is also shown …


Electronic Branching Ratio Of The Lepton, R. Ammar, Manoj Thulasidas Jan 1992

Electronic Branching Ratio Of The Lepton, R. Ammar, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

Using data accumulated by the CLEO I detector operating at the Cornell Electron Storage Ring, we have measured the ratio R=Γ(τ→eν¯eντ)Γ1 where Γ1 is the τ decay rate to final states with one charged particle. We find R=0.2231±0.0044±0.0073 where the first error is statistical and the second is systematic. Together with the measured topological one-charged-particle branching fraction, this yields the branching fraction of the τ lepton to electrons, Be=0.192±0.004±0.006.


Isospin Mass Splittings From Precision Measurements Of D*-D Mass Differences, D. Bortoletto, Manoj Thulasidas Jan 1992

Isospin Mass Splittings From Precision Measurements Of D*-D Mass Differences, D. Bortoletto, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

Using the decay modes, D*+→D+π0 and D*0→D0π0, we have measured the D*+−D+ and D*0−D0 mass differences to be 140±0.08±0.06 and 142.12±0.05±0.05 MeV, respectively. Combining these measurements with the Particle Data Group average for the D*+−D0 mass difference, we obtain isospin mass splittings for D*+−Dusp*0 and D+−D0 of 3.32±0.08±0.05 and 4.80±0.10 ±0.06 MeV. We discuss the implications of these measurements for models of isospin mass differences and model-dependent estimates of fD.


Measurement Of The Tau Lepton Electronic Branching Fraction, D. Akerib, M. Thulasidas Jan 1992

Measurement Of The Tau Lepton Electronic Branching Fraction, D. Akerib, M. Thulasidas

Research Collection School Of Computing and Information Systems

The tau lepton electron branching fraction has been measured with the CLEO II detector at the Cornell Electron Storage Ring as Be=0.1749±0.0014±0.0022, with the first error statistical and the second systematic. The measurement involves counting electron-positron annihilation events in which both taus decay to electrons, and normalizing to the number of tau-pair decays expected from the measured luminosity. Detected photons in these events constitute a definitive observation of tau decay radiation.


A Comparison Of The Effects Of Reading From A Vdu And From Paper As Measured In Terms Of Reading Speed And Comprehension, Elizabeth Payumo Jan 1992

A Comparison Of The Effects Of Reading From A Vdu And From Paper As Measured In Terms Of Reading Speed And Comprehension, Elizabeth Payumo

Theses: Doctorates and Masters

This study investigates the legibility and visual effects of eight combinations of font and colour on VDU and two different fonts on paper. Forty subjects, sixteen females and twenty-four males, were exposed to three of the ten different conditions, one in each of the set of readings, on either VDU or paper. They were asked to read different sets of stories in each condition on different days where each condition lasted for approximately two hours. Reading speed and comprehension scores were measured in every story read in the set of stories. The change of mood and physical symptoms states of …


The A.D.E. Taxonomy Of Spreadsheet Application Development, Maria Jean Hall Jan 1992

The A.D.E. Taxonomy Of Spreadsheet Application Development, Maria Jean Hall

Theses: Doctorates and Masters

Spreadsheets are a major application in end-user computing, one of the fastest growing areas of computing. Studies have shown that 30% of spreadsheet applications contain errors. As major decisions are often made with the assistance of spreadsheets, the control of spreadsheet applications is a matter of concern to enduser developers, managers, EDP auditors and computer professionals.

The application of appropriate controls to the spreadsheet development process requires prior categorisation of the spreadsheet application. The special-purpose A.D.E. (Application, Development, Environment) taxonomy of spreadsheet application development was evolved by mathematical taxonomic methods to categorise spreadsheet development projects to facilitate their management and …


Editing Digital Audio Using A Perceptual Model, J. Mark Goode Dec 1991

Editing Digital Audio Using A Perceptual Model, J. Mark Goode

Theses

In this paper we describe an intelligent system used to aid an audio recording producer in the selection of edit points in a musical sequence. It is possible to make meaningful recommendations concerning auditory input data without the ability to fully classify that data or interpret all outside goals. Perceptual modeling of the auditory input can allow sufficient reasoning ability for an intelligent system to be of use editing digital audio. To create a perceptual model, the information which can be extracted by the ear is embodied in several expert sections which communicate with a rule based decision maker via …


Communications Network For Distributed Real-Time Systems, Charles Silva Dec 1991

Communications Network For Distributed Real-Time Systems, Charles Silva

Theses

No abstract provided.


A Synthesis Technique Of General Petri Nets For Flexible Manufacturing And Multi-Rate Digital Signal Processing, Murthy S. Valluri Dec 1991

A Synthesis Technique Of General Petri Nets For Flexible Manufacturing And Multi-Rate Digital Signal Processing, Murthy S. Valluri

Theses

General Petri nets are useful for modeling flexible manufacturing system with multiple robots and workstations [KOH 90] and for multi-rate digital signal processing systems [CHA 91].. A problem of using Petri nets for modeling various systems is the large number of states generated. Various synthesis approaches have been proposed. Most of them do not deal with general Petri nets. Koh et. al. [KOH 90] invented a synthesis technique for generalized Petri nets. The purpose of this thesis is to extend their work by modifying the knitting technique by adding the Arc-Ratio rule.


Representation Of Graphical Deep Knowledge In An Object-Oriented Database System, Prasanna S. Venkatesh Dec 1991

Representation Of Graphical Deep Knowledge In An Object-Oriented Database System, Prasanna S. Venkatesh

Theses

Object-oriented approaches to the design of complex graphical interfaces have received an enormous impetus in the database and knowledge representation disciplines. As traditional CAD systems store information about all the objects for display purposes but do not store any knowledge for reasoning purposes, they are considered as "knowledge poor" and they cannot support efficient environments for design. In Artificial Intelligence the notion of "Graphical Deep Knowledge" has been proved successful to represent knowledge about objects for display purposes as well as reasoning purposes. To design "knowledge rich" systems which can support better graphical interfaces, the theory of "Graphical Deep Knowledge" …


Unix And Security: The Influences Of History, Eugene H. Spafford Dec 1991

Unix And Security: The Influences Of History, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


Three Letters On Computer Security And Society, Eugene H. Spafford Dec 1991

Three Letters On Computer Security And Society, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.