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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 …


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 …


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 …


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.


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.


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 …


The Group Spreadsheet, George Francis Morrissey Jr. Jan 1992

The Group Spreadsheet, George Francis Morrissey Jr.

UNF Graduate Theses and Dissertations

Groupware is fast becoming an important part of the computing world. This thesis reviews past history and research in which a group oriented spreadsheet is shown to have a real purpose in today's business world. A group oriented spreadsheet was implemented using a public domain package called The Spreadsheet Calculator. Spreadsheet users and programmers tested the implementation. The results and conclusions of this implementation are also presented.


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.


Measurement Of Τ Decays Involving Η Mesons, M. Artuso, M. Thulasidas Jan 1992

Measurement Of Τ Decays Involving Η Mesons, M. Artuso, M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


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 …


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" …


A Study In Systems Integration Architecture, Sashidhar M. Prasad Dec 1991

A Study In Systems Integration Architecture, Sashidhar M. Prasad

Theses

This Thesis studies the two architectures OSCA and ANSA which support the ODPSE principle in the first two parts. In the third part the framework for integrating these two architectures is described. The idea of integration architectures in relation to open architectures is studied using the enabling technologies.


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.


Migrating A C-Based Cad Tool To An Object-Oriented Database/C++ Environment: Conversion Costs And Performance Analysis, Mark A. Roth, Timothy M. Jacobs Dec 1991

Migrating A C-Based Cad Tool To An Object-Oriented Database/C++ Environment: Conversion Costs And Performance Analysis, Mark A. Roth, Timothy M. Jacobs

AFIT Documents

his paper examines the potential of object-oriented databases to support complex design applications. To do this we migrated the Magic very large scale integrated (VLSI) circuit design tool written in the C language to a new environment in which Magic's existing file management code is replaced with a C++ language interface to the commercial object-oriented database management system (OODBMS) product Object Store. In our initial implementation we found the performance of this tool as implemented on the OODBMS to be marginally faster than the tool as currently implemented with a flat file system in several critical areas. Increased functionality, including …


Visualization Of Four Dimensional Space And Its Applications (Ph.D. Thesis), Jianhua Zhou Dec 1991

Visualization Of Four Dimensional Space And Its Applications (Ph.D. Thesis), Jianhua Zhou

Department of Computer Science Technical Reports

No abstract provided.


An Efficient Neural Algorithm For The Multiclass Problem, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Dec 1991

An Efficient Neural Algorithm For The Multiclass Problem, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

One connectionist approach to the classification problem, which has gained popularity in recent years, is the use of backpropagation-trained feed-forward neural networks. In practice, however, we find that the rate of convergence of net output error is especially low when training networks for multi-class problems. In this paper, we show that while backpropagation will reduce the Euclidean distance between the actual and desired output vectors, the difference between some of the components of these vectors will actually increase in the first iteration. Furthermore, the magnitudes of subsequent weight changes in each iteration are very small, so that many iterations are …


The Fast Fourier Transform, Per Brinch Hansen Dec 1991

The Fast Fourier Transform, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

This tutorial discusses the fast Fourier transform, which has numerous applications in signal and image processing. The FFT computes the frequency components of a signal that has been sampled at n points in O( n log n) time. We explain the FFT and illustrate it by examples and Pascal algorithms. We assume that you are familiar with elementary calculus.


Efficient Maximum-Likelihood Soft-Decision Decoding Of Linear Block Codes Using Algorithm A, Yunghsiang S. Han, Carlos R.P. Hartmann, Chih-Chieh Chen Dec 1991

Efficient Maximum-Likelihood Soft-Decision Decoding Of Linear Block Codes Using Algorithm A, Yunghsiang S. Han, Carlos R.P. Hartmann, Chih-Chieh Chen

Electrical Engineering and Computer Science - Technical Reports

In this report we present a novel and efficient maximum-likelihood soft-decision decoding algorithm for linear block codes. The approach used here is to convert the decoding problem into a search problem through a graph which is a trellis for an equivalent code of the transmitted code. Algorithm A*, which uses a priority-first search strategy, is employed to search through this graph. This search is guided by an evaluation function f defined to take advantage of the information provided by the received vector and the inherent properties of the transmitted code. This function f is used to drastically reduce the search …


A Case Study In Software Reuse: The Rntds Architecture, Barry J. Stevens Dec 1991

A Case Study In Software Reuse: The Rntds Architecture, Barry J. Stevens

Computer Science Theses & Dissertations

It has been asserted that the most significant gains in software productivity will come from increased levels of software reuse. Some economic models for predicting savings through software reuse exist, but none are based on actual project experience. This paper surveys those models and presents the results of a case study, the Restructured Naval Tactical Data Systems (RNTDS) architecture, in the light of those models. According to the models, software reuse via the RNTDS architecture has enabled the production of fourteen major computer programs at five to twenty-one percent of the cost to create them without software reuse. Organizational characteristics …


Establishing A Methodology For Evaluation And Selecting Computer Aided Software Engineering Tools For A Defined Software Engineering Environment At The Air Force Institute Of Technology School Of Engineering, Jody L. Mattingly Dec 1991

Establishing A Methodology For Evaluation And Selecting Computer Aided Software Engineering Tools For A Defined Software Engineering Environment At The Air Force Institute Of Technology School Of Engineering, Jody L. Mattingly

Theses and Dissertations

This thesis identifies the software engineering environment (SEE) as it exists at the Air Force Institute of Technology (AFIT) School of Engineering. It also describes the software process model employed and the software development methods presented as part of the curriculum. Based on this information, criteria was established to evaluate computer aided software engineering (CASE) tools being considered for integration into the SEE. Each criterion was weighted to indicate its importance when selecting CASE tools. The criteria were further used to establish a methodology to be used to evaluate and select the CASE tools under consideration as well as future …


Effect Of Spatial Locality Prefetching On Structural Locality, Dirk D. Schalch Dec 1991

Effect Of Spatial Locality Prefetching On Structural Locality, Dirk D. Schalch

Theses and Dissertations

The purpose of this research was to analyze the effect that spatial locality prefetching in cache memory has on the structural locality of program memory referencing behavior. To examine this, a software simulator was built to model a proposed two-level cache memory subsystem. The proposed subsystem was designed to use spatial locality prefetching to exploit the structural locality contained in executing computer workloads. New memory referencing models were developed to incorporate the combined use of structural locality and spatial locality prefetching. From these models, equations were derived to predict the hit rates for both caches. Combined with the state transition …


Three-Dimensional Medical Image Registration Using A Patient Space Correlation Technique, Patrick J. Rizzuto Jr. Dec 1991

Three-Dimensional Medical Image Registration Using A Patient Space Correlation Technique, Patrick J. Rizzuto Jr.

Theses and Dissertations

The routine clinical use of three-dimensional data provided by modern medical imaging procedures is often impeded by the difficulty in accurately correlating the resultant volume datasets. These data are frequently obtained at different times using the same modality, or images of the same patient are sometimes produced using more than one imaging modality. In order to analyze the similarities and differences between such images, it is necessary for the medical imaging data to be spatially aligned using a process known as image registration. This research investigated a structure-based image registration technique based upon simple, three-dimensional relationships among user identified landmarks. …


Design Of Style-V — A Translator To Convert Standard Vhdl Into A Stylized Form For Automated Microcode Generation, Dennis A. Rumbley Dec 1991

Design Of Style-V — A Translator To Convert Standard Vhdl Into A Stylized Form For Automated Microcode Generation, Dennis A. Rumbley

Theses and Dissertations

This thesis provides an analysis and preliminary design of Style V, a source-to-source computer language translator. Style-V converts IEEE standard VHDL into a special style of VHDL defined for a commercial tool, the Integrated Design Automation System (IDAS). Thirteen mappings between standard VHDL and the IDAS subset were identified. The mappings were analyzed using Domain Analysis and Modern Structured Analysis techniques. Four processes covering several of the mappings were completely analyzed. One mapping to convert CASE statements to IF statements was implemented. Since the IDAS restricts designs to bit logic, a method for representing multilevel logic with bit logic was …


A Spatially Partitioned Parallel Simulation Of Colliding Objects, Robert S. Moser Dec 1991

A Spatially Partitioned Parallel Simulation Of Colliding Objects, Robert S. Moser

Theses and Dissertations

This study investigated the application of a conservative synchronization paradigm to the classical, distributed pool balls simulation executed on an eight node, Intel iPSC/2 hypercube. Wieland's concept of spatial partitioning and limited data replication was used. Analysis has shown that 100% parallelization of execution is possible in a conservative environment via assignment of multiple sectors to nodes. Two conservative formulations for minimum safe time were derived. A tradeoff exists between scalability and efficiency. Optimum sectoring prediction has been shown possible through application of linear regression techniques. The results of this research reveal that a conservative approach to distributed, discrete event …


Improved Task Scheduling For Parallel Simulations, Andrew E. Mcnear Dec 1991

Improved Task Scheduling For Parallel Simulations, Andrew E. Mcnear

Theses and Dissertations

The objective of this investigation is to design, analyze, and validate the generation of optimal schedules for simulation systems. Improved performance in simulation execution times can greatly improve the return rate of information provided by such simulations resulting in reduced development costs of future computer/electronic systems. Optimal schedule generation of precedence-constrained task systems including iterative feedback systems such as VHDL or war gaming simulations for execution on a parallel computer is known to be N P-hard. Efficiently parallelizing such problems takes full advantage of present computer technology to achieve a significant reduction in the search times required. Unfortunately, the extreme …


An Application Of The Object-Oriented Paradigm To A Flight Simulator, Dennis J. Simpson Dec 1991

An Application Of The Object-Oriented Paradigm To A Flight Simulator, Dennis J. Simpson

Theses and Dissertations

This thesis describes the object-oriented software development techniques that were used to analyze, design and implement a flight simulator. The objective of this thesis was to present a comprehensive object-oriented software development methodology and show how it was used in constructing an actual application. An extensive review of current object-oriented practices is presented along with the methods that were used to take the flight simulator from analysis to design and through to implementation. The description of the methodology concentrates upon the design and implementation phases of the object-oriented software lifecycle. Examples from the design of the flight simulator demonstrate how …