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An Abstract Data Model For The Idef0 Graphical Analysis Language, Gerald R. Morris, Thomas C. Hartrum, Mark A. Roth Jan 1990

An Abstract Data Model For The Idef0 Graphical Analysis Language, Gerald R. Morris, Thomas C. Hartrum, Mark A. Roth

AFIT Documents

IDEF0 is the United States Air Force's ICAM (Integrated Computer Aided Manufacturing) Definition Method Zero graphical analysis language, a subset of Ross' Structured Analysis (SA) language. The language is also an excellent methodology for performing a requirements-phase analysis for any software development project. We present an abstract data model for IDEF0 using entity-relationship diagrams. This model helps to mitigate some of the ambiguities inherent in IDEF0. The model is divided into two parts representing the analysis data (the essential data model) and the graphical data (the drawing data model). This dual modeling approach allows for the …

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A Functional Language With Classes, Mike Veaven, Ryan Stanisfer, Dan Wetklow Jan 1990

A Functional Language With Classes, Mike Veaven, Ryan Stanisfer, Dan Wetklow

Department of Computer Science Technical Reports

No abstract provided.

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Queueing Models Of Secondary Storage Devices, Edward G. Coffman Jan 1990

Queueing Models Of Secondary Storage Devices, Edward G. Coffman

Department of Computer Science Technical Reports

No abstract provided.

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Geometric Computations With Algebraic Varieties Of Bounded Degree, Chanderjit L. Bajaj Jan 1990

Geometric Computations With Algebraic Varieties Of Bounded Degree, Chanderjit L. Bajaj

Department of Computer Science Technical Reports

No abstract provided.

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Algebraic Surface Design With Hermite Interpolation, Chandrajit L. Bajaj, Insung Ihm Jan 1990

Algebraic Surface Design With Hermite Interpolation, Chandrajit L. Bajaj, Insung Ihm

Department of Computer Science Technical Reports

No abstract provided.

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Mapping Finite Element Graphs On Hypercubes, Yeh-Ching Chung, Sanjay Ranka Jan 1990

Mapping Finite Element Graphs On Hypercubes, Yeh-Ching Chung, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

In parallel computing, it is important to map a parallel program onto a parallel computer such that the total execution time of a parallel program is minimized. In general, a parallel program and a parallel computer can be represented by a task graph (TG) and a processor graph (PG), respectively. For a TG, nodes represent tasks of a parallel program and edges denote the data communication needed between tasks. The weights associated with nodes and edges represent the computational load and communication cost, respectively. For a PG, nodes and edges denote processors and communication channels, respectively. By using the graph …

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An Architecture For Distributed Multimedia Database Systems, P. B. Berra, C.Y.R. Chen, A. Ghafoor, C. C. Lin Jan 1990

An Architecture For Distributed Multimedia Database Systems, P. B. Berra, C.Y.R. Chen, A. Ghafoor, C. C. Lin

Electrical Engineering and Computer Science - All Scholarship

In the past few years considerable demand for user oriented multimedia information systems has developed. These systems must provide a rich set of functionality so that new, complex, and interesting applications can be addressed. This places considerable importance on the management of diverse data types including text, images, audio and video. These requirements generate the need for a new generation of distributed heterogeneous multimedia database systems. In this paper we identify a set of functional requirements for a multimedia server considering database management, object synchronization and integration, and multimedia query processing. A generalization of the requirements to a distributed system …

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Using Annotated C++, Marshall P. Cline, Doug Lea Jan 1990

Using Annotated C++, Marshall P. Cline, Doug Lea

Electrical Engineering and Computer Science - All Scholarship

A++ (‘‘Annotated C++’’) is both a formalism and a proposed CASE tool for annotating C++ code with object-oriented specifications, assertions, and related semantic information. Annotations provide programmers with a useful means for approaching class design, exceptions, correctness, standardization, software reusability and related issues in software engineering with C++. This paper shows how A++ provides arbitrarily fine granularity to the C++ type system, how it automates and streamlines exception testing, how it can aid in standardization of software components, and how it can safely remove redundant exception tests.

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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, January 1990, College Of Engineering And Computer Science, Wright State University Jan 1990

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, January 1990, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

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An Underwater Science And Resource Database Management System And Proposed Applications To Marine Geographic Information Systems, Ivar Babb Jan 1990

An Underwater Science And Resource Database Management System And Proposed Applications To Marine Geographic Information Systems, Ivar Babb

Marine Affairs Theses and Major Papers

The National Undersea Research Program (NURP) is a federally-funded program that provides scientists with modern in situ technology that allows them to conduct research that goes beyond the constraints of traditional oceanographic methodology. NURP is comprised of five regional centers that administer underwater science, and through the principal investigators that are supported generate a vast quantity of diverse data. This data and information bank consists of the following: raw environmental data, logistical data, locational data, information about the scientists, video and still photograph documentation, and publication information. This paper describes the theory behind the implementation of a Database Management System …

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The Use Of Remote Sensing Techniques And Geographic Information Systems By Coastal Managers In Rhode Island, Margaret H. Sano Jan 1990

The Use Of Remote Sensing Techniques And Geographic Information Systems By Coastal Managers In Rhode Island, Margaret H. Sano

Marine Affairs Theses and Major Papers

Planners and managers must understand the physical and anthropogenic changes taking place within the coastal zone to provide effective management. Remote sensing techniques and Geographic Information Systems (GIS) are excellent tools for contributing data and analytical capabilities to identify possible conflicts within the coastal zone. This study examines the potential and actual use of these technologies by coastal managers within Rhode Island. Potential usage is discussed in terms of the range of data available and the feasibility of using the data for coastal problems. Also, GIS capabilities in Rhode Island are explored. Finally a survey designed to measure the actual …

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Arithmetic Classification Of Perfect Models Of Stratified Programs (Addendum), Krzysztof R. Apt, Howard A. Blair Jan 1990

Arithmetic Classification Of Perfect Models Of Stratified Programs (Addendum), Krzysztof R. Apt, Howard A. Blair

Electrical Engineering and Computer Science - Technical Reports

RECURSION-FREE PROGRAMS The following section completes the analysis of arithmetic complexity of perfect models and has been inadvertently omitted in the previous version of the paper. We say that a general program P is recursion-free if in its dependency graph Dp there is no cycle. Clearly recursion-free programs form a subclass of stratified programs. Recursion-free programs form a very simple generalization of the class of hierarchical programs introduced in [C78]. Hierarchical programs satisfy an additional condition on variable occurrences in clauses that prevents floundering, i.e. a forced selection of a non-ground negative literal in an SLDNF- derivation. In this section …

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Pumps : A Method Of Financially Assessing Groundwater Pumping Used To Mitigate Salinity In South-Western Australia, Richard J. George Dr Jan 1990

Pumps : A Method Of Financially Assessing Groundwater Pumping Used To Mitigate Salinity In South-Western Australia, Richard J. George Dr

Resource management technical reports

No abstract provided.

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Ua66/3/3 Journal Of The A. C. M., Wku Association For Computing Machinery Jan 1990

Ua66/3/3 Journal Of The A. C. M., Wku Association For Computing Machinery

Student Organizations

Journal created by and about the WKU Association for Computing Machinery a student organization sponsored by WKU Computer Science.

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Faster Circuits And Shorter Formulas For Multiple Addition, Multiplication And Symmetric Boolean Functions, Michael Paterson, Uri Zwick, Nicholas Pippenger Jan 1990

Faster Circuits And Shorter Formulas For Multiple Addition, Multiplication And Symmetric Boolean Functions, Michael Paterson, Uri Zwick, Nicholas Pippenger

All HMC Faculty Publications and Research

A general theory is developed for constructing the shallowest possible circuits and the shortest possible formulas for the carry-save addition of n numbers using any given basic addition unit. More precisely, it is shown that if BA is a basic addition unit with occurrence matrix N, then the shortest multiple carry-save addition formulas that could be obtained by composing BA units are of size n1p+o(1)/, where p is the unique real number for which the Lp norm of the matrix N equals 1. An analogous result connects the delay matrix M of the basic addition unit BA and the minimal …

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Dawgs - A Distributed Compute Server Utilizing Idle Workstations, Henry Clark, Bruce M. Mcmillin Jan 1990

Dawgs - A Distributed Compute Server Utilizing Idle Workstations, Henry Clark, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

A collection of powerful workstations interconnected by a local area network can be utilized as compute servers when left idle by their owners. DAWGS allows users to submit jobs for execution on an idle workstation somewhere on a local area network. DAWGS uses a distributed scheduler and a bidding scheme to determine on which machine to run a process. DAWGS can properly redirect all the I/O of a remotely executing process and can checkpoint and then subsequently restart the process, even if the restart is on a different machine than the checkpoint. Our method is different from other work in …

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Data Acquisition And Control Program For Chromatographic And Spectroscopic Studies, M. Keith Hudson, William G. Hood, Robert Henson Jan 1990

Data Acquisition And Control Program For Chromatographic And Spectroscopic Studies, M. Keith Hudson, William G. Hood, Robert Henson

Journal of the Arkansas Academy of Science

An IBMPC compatible computer was interfaced to an Ithaco 3962 lock-in-amplifier. The computer controlled the functions of the lock-in-amplifier, acquired and stored data, and allowed for real time or off-line processing of data. Computer/amplifier connection was made via RS-232-C serial interface. Programmed in Microsoft Quick BASIC, the computer assumed the role of a dedicated chromatographic integrator. This reduced the overall instrumentation expense by eliminating a dedicated chromatographic integrator. The computer program supplied much greater flexibility in control and data interpretation. To show its utility, the program was applied to a study of the infrared emission from a flame upon the …

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Data Security: The Securing Of Computer Installations And Data Sets, Willy B. Kuehnle Jan 1990

Data Security: The Securing Of Computer Installations And Data Sets, Willy B. Kuehnle

Theses

No abstract provided.

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Planar Graphs And Sparse Graphs From Efficient Motion Planning In The Plane, L Paul Chew Jan 1990

Planar Graphs And Sparse Graphs From Efficient Motion Planning In The Plane, L Paul Chew

Computer Science Technical Reports

Given a source, a destination, and a number of obstacles in the plane, the Motion Planning Program is to determine the best path to move an object (a robot) from the source to the destination without colliding with any of the obstacles. For us, motion is restricted to the plane, the robot is represented by a point, and the obstacles are represented by a set of polygons with a total of n vertices among all the polygonal obstacles.

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Building Voronoi Diagrams For Convex Polygons In Linear Expected Time, L Paul Chew Jan 1990

Building Voronoi Diagrams For Convex Polygons In Linear Expected Time, L Paul Chew

Computer Science Technical Reports

Let P be a list of points in the plane such that the points of P taken in order form the vertices of a convex polygon. We introduce a simple, linear expected-time algorithm for finding the Voronoi diagram of the points in P. Unlike previous results on expected-time algorithms for Voronoi diagrams, this method does not require any assumptions about the distribution of points. With minor modifications, this method can be used to design fast algorithms for certain problems involving unrestricted sets of points. For example, fast expected-time algorithms can be designed to delete a point from a Voronoi diagram, …

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Term Reduction Using Directed Congruence Closure, L Paul Chew Jan 1990

Term Reduction Using Directed Congruence Closure, L Paul Chew

Computer Science Technical Reports

Many problems in computer science can be described in terms of reduction rules that tell how to transform terms. Problems that can be handled in this way include interpreting programs, implementing abstract data types, and proving certain kinds of theorems. A terms is said to have a normal form if it can be transformed, using the reduction rules, into a term to which no further reduction rules apply. In this paper, we extend the Congruence Closure Algorithm, an algorithm for finding the consequences of a finite set of equations, to develop Directed Congruence Closure, a technique for finding the normal …

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Applying The Take-Grant Protection Model, Matt Bishop Jan 1990

Applying The Take-Grant Protection Model, Matt Bishop

Computer Science Technical Reports

The Take-Grant Protection Model has in the past been used to model multilevel security hierarchies and simple protection systems. The models are extended to include theft of rights and sharing of information, and additional security policies are examined. The analysis suggests that in some cases the basic rules of the Take-Grant Protection Model should be augmented to represent the policy properly; when appropriate, such modifications are made and their effects with respect to the policy and its Take-Grant representations are discussed.

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Administrator's Guide To The Digital Signature Facility "Rover", Matt Bishop Jan 1990

Administrator's Guide To The Digital Signature Facility "Rover", Matt Bishop

Computer Science Technical Reports

This document describes the installation and maintenance of the rover utility, which provides a digital signature capability for internet messages.

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Effects Of Replication On Data Availability, Donald B. Johnson, Larry Raab Jan 1990

Effects Of Replication On Data Availability, Donald B. Johnson, Larry Raab

Computer Science Technical Reports

In this paper we examine the effects of replication on the availability of data in a large network. This analysis differs from previous analyses in that it compares the performance of a dynamic consistency control protocol not only to that of other consistency control protocols, but also to the performance of non-replication and to an upper bound on data availability. This analysis also differes in that we gather extensive simulations on large networks subject to partitions at realistically high component reliabilities. We examine the dynamic consistency protocol presented by Jajodia and Mutchler [9, 12] and by Long and Paris[18] along …

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Finding Optimal Quorum Assigments For Distributed Databases, Donald B. Johnson, Larry Raab Jan 1990

Finding Optimal Quorum Assigments For Distributed Databases, Donald B. Johnson, Larry Raab

Computer Science Technical Reports

Replication has been studied as a method of increasing the availability of a data item in a distributed database subject to component failures and consequent partitioning. The potential for partitioning requires that a protocol be employed which guarantees that any access to a data item is aware of the most recent update to that data item. By minimizing the number of access requests denied due to this constraint, we maximize availability. In the event that all access requests are reads, placing one copy of the data item at each site clearly leads to maximum availability. The other extreme, all access …

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A Proactive Password Checker, Matt Bishop Jan 1990

A Proactive Password Checker, Matt Bishop

Computer Science Technical Reports

Password selection has long been a difficult issue; traditionally, passwords are either assigned by the computer or chosen by the user. When the computer does the assignments, the passwords are often hard to remember; when the User makes the selection, the passwords are often easy to guess. This paper describes a technique, and a mechanism, to allow users to select passwords which to them are easy to remember but to others would be very difficult to guess. The technique is site, user, and group configurable, and allows rapid changing of constraints impossed upon the passwords. Although experience with this technique …

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Grades - A Computer Based Score Management System For The Iigs, Charles Patrick Wahle Jan 1990

Grades - A Computer Based Score Management System For The Iigs, Charles Patrick Wahle

All Graduate Projects

This project involved the creation of an electronic gradebook designed to realistically meet the needs of classroom teachers. The computer source code was written in Pascal, a compiled language that allowed fast execution of any part of the program. The electronic gradebook called GradeS uses the graphic Desktop Intert'ace. It tracks up to 42 students per class, allowing up to 50 assignments per grading period. An unlimited number of classes can be stored on data disks. It produces four different types of whole class and individual student reports both on the screen and the printer. The project includes a report …

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A Dsm-Iii-R Study Of Computer Addiction Among Iowa Computer Users, Randy Young Jan 1990

A Dsm-Iii-R Study Of Computer Addiction Among Iowa Computer Users, Randy Young

CCAC Theses and Dissertations

No abstract provided.

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A Simulation Testbed For Image Compression Algorithms, Andrew Francis Laine Jan 1990

A Simulation Testbed For Image Compression Algorithms, Andrew Francis Laine

All Computer Science and Engineering Research

This paper presents an overview of the design and development of a real-time (30 frames/sec) simulation testbed for evaluating and comparing image compression algorithms. The system was motivated by the need to visualize the performance of a novel compression algorithm when operating on moving pictures originating from "live" video sources. The simulation utilities are designed to exploit the parallelism of a Pixar Image Computer and high-throughput of a parallel disk assembly. The design of two key utilities are discussed: (1) A program to format precomputed four channel (RGBA) 256 X 256 color frames onto a parallel disk assembly. (2) A …

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Linda Implementations Using Monitors And Message Passing, Alan L. Leveton Jan 1990

Linda Implementations Using Monitors And Message Passing, Alan L. Leveton

UNF Graduate Theses and Dissertations

Linda is a new parallel programming language that is built around an interprocess communication model called generative communication that differs from previous models in specifying that shared data be added in tuple form to an environment called tuple space, where a tuple exists independently until some process chooses to use it. Interesting properties arise from the model, including space and time uncoupling as well as structured naming. We delineate the essential Linda operations, then discuss the properties of generative communication. We are particularly concerned with implementing Linda on top of two traditional parallel programming paradigms - process communication through globally …

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