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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: 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 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.


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 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. …


On Hamiltonian Line Graphs, Zhi-Hong Chen Jan 1992

On Hamiltonian Line Graphs, Zhi-Hong Chen

Scholarship and Professional Work - LAS

No abstract provided.


Applying Metrics To Rule-Based Systems, Paul Doyle, Renaat Verbruggen Jan 1992

Applying Metrics To Rule-Based Systems, Paul Doyle, Renaat Verbruggen

Other

Since the introduction of software measurement theory in the early seventies it has been accepted that in order to control software it must first be measured. Unambiguous and reproducible measurements are considered to be the most useful in controlling software productivity, costs and quality, and diverse sets of measurements are required to cover all aspects of software. This paper focuses on measures for rule-based language systems and also describes a process for developing measures for other non-standard 3GL development tools. This paper uses KEL as an example and the method allows the re-use of existing measures and indicates if and …


Proving Functionally Difficult Problems Through Model Generation, Richard Rankin, Ralph W. Wilkerson Jan 1992

Proving Functionally Difficult Problems Through Model Generation, Richard Rankin, Ralph W. Wilkerson

Computer Science Faculty Research & Creative Works

Satchmo [MA88] is a Theorem Prover Implemented in Prolog Which Attempts to Provide Satisfiability Checking through Model Generation. This Paper Gives a Brief Introduction to SATCHMO and Reports Extensions to the Original Work Which Allow SATCHMO to Solve Problems Previously Considered to Be Finitely Unprovable within the SATCHMO System. the Specific Problems Are from [PE86, MO85, LU85] and Were Designed to Convert Simple Propositional Logic Problems into Functionally Difficult First Order Problems. Although the Benefits of using the SATCHMO System Are Many, the Fact that It Could Not Offer Proofs for a Set of Problems Provable in Other Systems is …


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 …


Executing Multidatabase Transactions, Mansoor Ansari, Marek Rusinkiewicz, Linda Ness, Amit P. Sheth Jan 1992

Executing Multidatabase Transactions, Mansoor Ansari, Marek Rusinkiewicz, Linda Ness, Amit P. Sheth

Kno.e.sis Publications

In a multidatabase environment, the traditional transaction model has been found to be too restrictive. Therefore, several extended transaction models have been proposed in which some of the requirements of transaction, such as isolation or atomicity, are optional. The authors describe one of such extensions, the flexible transaction model and discuss the scheduling of transactions involving multiple autonomous database systems managed by heterogeneous DBMS.

The scheduling algorithm for flexible transactions is implemented using L.0, a logically parallel language which provides a framework for concisely specifying the multidatabase transactions and for scheduling them. The key aspects of a flexible transaction specification, …


Distributed Ray Casting For High-Speed Volume Rendering, Patricia L. Brightbill Jan 1992

Distributed Ray Casting For High-Speed Volume Rendering, Patricia L. Brightbill

Theses and Dissertations

The volume rendering technique known as ray casting or ray tracing is notoriously slow for large volume sizes, yet provides superior images. A technique is needed to accelerate ray tracing volumes without depending on special purpose or parallel computers. The realization and improvements in distributed computing over the past two decades has motivated its use in this work. This thesis explores a technique to speedup ray casting by distributed programming. The work investigates the possibility of dividing the volume among general purpose workstations and casting rays (using Levoy's front-to-back algorithm) through each subvolume independently. The final step being the composition …


How To Encrypt /Usr/Dict/Words In About A Second, Peter Su, Matt Bishop Jan 1992

How To Encrypt /Usr/Dict/Words In About A Second, Peter Su, Matt Bishop

Computer Science Technical Reports

We present an implementation of the Data Encryption Standard on the Connection Machine architecture. The DES encryption algorithm is ideally suited to the Connection Machine because it consists of bit serial operations, and thousands of encryptions can be done in parallel, independently of one another. Thus, our code encrypts passwords about ten times faster than the fastest competition that we know about. In addition, the nature of the Connection Machine's architecture is such that some of the optimizations that make DES run much faster on conventional architectures have no effect on the performance of the Connection Machine. Our comparison of …


Concurrent Local Search For Fast Proximity Algorithms On Parallel And Vector Architectures, Peter Su Jan 1992

Concurrent Local Search For Fast Proximity Algorithms On Parallel And Vector Architectures, Peter Su

Computer Science Technical Reports

This paper presents a fast algorithm for solving the all-nearest-neighbors problem. The algorithm uses a data parallel style of programming which can be efficiently utilized on a variety of parallel and vector architectures [4,21,26]. I have implemented the algorithm in C on one such architecture, the Cray Y-MP. On one Cray CPU, the implementation is about 19 times faster than a fast sequential algorithm running on a Sparc workstation. The main idea in the algorithm is to divide the plane up into a fixed grid of cells, or buckets. When the points are well distributed, the algorithm processes each query …


On The De Bruijn Torus Problem, Glenn Hurlbert, Garth Isaak Jan 1992

On The De Bruijn Torus Problem, Glenn Hurlbert, Garth Isaak

Computer Science Technical Reports

A (kn;n)k-de Bruijn Cycle is a cyclic k-ary sequence with the property that every k-ary n-tuple appears exactly once contiguously on the cycle. A (kr, ks; m, n)k-de Bruijn Torus is a k-ary krXks toroidal array with the property that every k-ary m x n matrix appears exactly once contiguously on the torus. As is the case with de Bruijn cycles, the 2-dimensional version has many interesting applications, from coding and communications to pseudo-random arrays, spectral imaging, and robot self-location. J.C. Cock proved the existence of such tori for all m, n, and k, and Chung, Diaconis, and Graham asked …


Grounding Via Scanning: Cooking Up Roles From Scratch, Doug Blank, Michael Gasser Jan 1992

Grounding Via Scanning: Cooking Up Roles From Scratch, Doug Blank, Michael Gasser

Computer Science Faculty Research and Scholarship

No abstract provided.


A Case For The Use Of Application Generators In The Creation Of Software For The Hotel Industry, Peter O'Connor, Ciaran Mcdonnell Jan 1992

A Case For The Use Of Application Generators In The Creation Of Software For The Hotel Industry, Peter O'Connor, Ciaran Mcdonnell

Conference papers

The article makes the case for the use of Program Generators in producing software for the Hotel and Catering Industry


Instructional Use Of Computers For Entry-Level Physical Therapy Education In The United States, Edmund M. Kosmahl Jan 1992

Instructional Use Of Computers For Entry-Level Physical Therapy Education In The United States, Edmund M. Kosmahl

CCAC Theses and Dissertations

Little was known about the value of computer assisted instruction (CAl) for entry-level physical therapy (PT) education. Factors that affect implementation and use of CAl in entry-level PT education had not been identified. Because of this paucity of information, decision-making about the implementation and use of CAl in entry-level PT education had been hampered.

This study used mail questionnaire survey methods to find:

  1. The extent of use of computer-assisted instruction (CAl) in entry-level physical therapy (PT) education.
  2. The perceived value of CAl compared to more traditional instructional methods for entry-level PT education.
  3. What factors affect implementation and use of CAl …


Smimd - A Synchronous Multiple Instruction Multiple Data Computer Architecture, Cathy C. Roberts Jan 1992

Smimd - A Synchronous Multiple Instruction Multiple Data Computer Architecture, Cathy C. Roberts

Computer Science Theses & Dissertations

This thesis assesses the feasibility of utilizing a hypercube interconnect topology to link a heterogeneous processor array in a very long instruction word (VLIW) computer architecture. The research focused upon the selection of a suitable arrangement of processors for the computer and the subsequent demonstration of the architecture's capability to handle simple loop iterations. Previous attempts at VLIW computer design are summarized, the new SMIMD architecture is presented, and suggestions for future research are given. The thesis concludes with results of the initial performance evaluations of the architecture design.


High Performance Issues In Image Processing And Computer Vision, Jingyuan Zhang Jan 1992

High Performance Issues In Image Processing And Computer Vision, Jingyuan Zhang

Computer Science Theses & Dissertations

Typical image processing and computer vision tasks found in industrial, medical, and military applications require real-time solutions. These requirements have motivated the design of many parallel architectures and algorithms. Recently, a new architecture called the reconfigurable mesh has been proposed. This thesis addresses a number of problems in image processing and computer vision on reconfigurable meshes.

We first show that a number of low-level descriptors of a digitized image such as the perimeter, area, histogram and median row can be reduced to computing the sum of all the integers in a matrix, which in turn can be reduced to computing …


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 …


Energy-Related Feature Abstraction For Handwritten Digit Recognition, Thomas H. Fuller Jr. Jan 1992

Energy-Related Feature Abstraction For Handwritten Digit Recognition, Thomas H. Fuller Jr.

All Computer Science and Engineering Research

Most handwritten character recognizers use either graphical (static) or first-order dynamic data. Our research speculates that the mental signal to write a digit might be partially encoded as an energy profile. We used artificial neural networks (ANN) to analyze energy-related features (first and second time derivatives) of handwritten digits of 20 subjects and later 40 subjects. An experimenal environment was developed on a NeXTstation with a real-time link to a pen-based GO computer. Although such an experiment cannot confirm an energy profile encoded in the writer, it did indicate the usefulness of energy-related features by recognizing 94.5% of the 600 …


Flattening C++ Classes, Umesh Bellur, Al Villarica, Kevin Shank, Imram Bashir, Doug Lea Jan 1992

Flattening C++ Classes, Umesh Bellur, Al Villarica, Kevin Shank, Imram Bashir, Doug Lea

Center for Advanced Systems and Engineering

Inheritance with derived classes and virtual functions are key design concepts in C++. Despite this, their use can result in significant degradation of run time performance. We present a class flattening tool, which we believe will help eliminate the overhead associated with virtual functions in C++ programs. A flattener may also prove useful in the reuse, debugging, and understanding of C++ components. This report deals with the issues associated with flattening, and then presents a detailed design of such a tool.


Software Support For Irregular And Loosely Synchronous Problems, Alok Choudhary, Geoffrey C. Fox, Sanja Ranka, Seema Hiranandani Jan 1992

Software Support For Irregular And Loosely Synchronous Problems, Alok Choudhary, Geoffrey C. Fox, Sanja Ranka, Seema Hiranandani

Northeast Parallel Architecture Center

A large class of scientific and engineering applications may be classified as irregular and loosely synchronous from the perspective of parallel processing. We present a partial classification of such problems. This classification has motivated us to enhance Fortran D to provide language support for irregular, loosely synchronous problems. We present techniques for parallelization of such problems in the context of Fortran D.


Scheduling Regular And Irregular Communication Patterns On The Cm-5, Ravi Ponnusamy, Rajeev Thakur, Alok Choudhary, Geoffrey C. Fox Jan 1992

Scheduling Regular And Irregular Communication Patterns On The Cm-5, Ravi Ponnusamy, Rajeev Thakur, Alok Choudhary, Geoffrey C. Fox

Northeast Parallel Architecture Center

In this paper, we study the communication characteristics of the CM-5 and the performance effects of scheduling regular and irregular communication patterns on the CM-5. We consider the scheduling of regular communication patterns such as complete exchange and broadcast. We have implemented four algorithms for complete exchange and studied their performances on a 2D FFT algorithm. We have also implemented four algorithms for scheduling irregular communication patterns and studied their performance on the communication patterns of several synthetic as well as real problems such as the conjugate gradient solver and the Euler solver.


Which Applications Can Use High Performance Fortran And Fortran-D: Industry Standard Data Parallel Languages?, Alok Choudhary, Geoffrey C. Fox, Tomasz Haupt, S. Ranka Jan 1992

Which Applications Can Use High Performance Fortran And Fortran-D: Industry Standard Data Parallel Languages?, Alok Choudhary, Geoffrey C. Fox, Tomasz Haupt, S. Ranka

Northeast Parallel Architecture Center

In this paper, we present the first, preliminary results of HPF/Fortran-D language analysis based on compiling and running benchmark applications using a prototype implementation of HPF/Fortran-D compiler. The analysis indicate that the HPF is a very convenient tool for programming many applications on massively parallel and/or distributed systems. In addition, we cumulate experience on how to parallelize irregular problems to extend the scope of Fortran-D beyond HPF and suggest future extensions to the Fortran standard.


Compiling Distribution Directives In A Fortran 90d Compiler, Zeki Bozkus, Alok Choudhary, Geoffrey C. Fox, Sanjay Ranka Jan 1992

Compiling Distribution Directives In A Fortran 90d Compiler, Zeki Bozkus, Alok Choudhary, Geoffrey C. Fox, Sanjay Ranka

Northeast Parallel Architecture Center

Data Partitioning and mapping is one of the most important steps of in writing a parallel program; especially data parallel one. Recently, Fortran D, and subsequently, High Performance Fortran (HPF) have been proposed to allow users to specify data distributions and alignments for arrays in programs. This paper presents the design of a Fortran 90D compiler that takes a Fortran 90D program as input and produces a node program + message passing calls for distributed memory machines. Specifically, we present the design of the Data Partitioning Module that processes the alignment and distribution directives and illustrate what are the important …


Global Domination Of Factors Of A Graph, Julie R. Carrington Jan 1992

Global Domination Of Factors Of A Graph, Julie R. Carrington

Retrospective Theses and Dissertations

A factoring of a graph G = (V, E) is a collection of spanning subgraphs F1, F2, ... , Fk, known as factors into which the edge set E has been partitioned. A dominating set of a graph is a set of nodes such that every node in the graph is either contained in the set or has an edge to some node in the set. Each factor Fi is itself a graph and so has a dominating set. This set is called a local dominating set or LDS. An LDS of minimum …


Program Maintenance And Code Reuse: Object Oriented Versus Procedure Oriented Programming, Beiramali Moradi Jan 1992

Program Maintenance And Code Reuse: Object Oriented Versus Procedure Oriented Programming, Beiramali Moradi

Theses

The purpose of this thesis is to address the problem of the increasing cost of program maintenance in the data processing world. On average, programmers today spend 60% of their time in program maintenance and that figure is increasing at an estimated rate of 1 % each year. The cost is staggering and almost every business would like to find ways of reducing maintenance costs. One way to help reduce maintenance and development costs is to improve code reusability. Both maintenance programming and code reusability are the focus of this thesis.

Today's most commonly used programming language style is procedure …


The Power Of The Middle Bit, Frederic Green, Johannes Kobler, Jacobo Toran Jan 1992

The Power Of The Middle Bit, Frederic Green, Johannes Kobler, Jacobo Toran

Computer Science

The class of languages that can be recognized in polynomial time with the additional information of one bit from a #P function is studied. In particular, it is shown that every ModkP class and every class contained in PH are low for this class. These results are translated to the area of circuit complexity using MidBit (middle bit) gates. It is shown that every language in ACC can be computed by a family of depth-2 deterministic circuits of size 2 to the (log n)c power with a MidBit gate at the root and AND-gates of fan-in (log n)c at the …


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 …