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An Interpreter for the Basic Programming Language (open access)

An Interpreter for the Basic Programming Language

In this thesis, the first chapter provides the general description of this interpreter. The second chapter contains a formal definition of the syntax of BASIC along with an introduction to the semantics. The third chapter contains the design of data structure. The fourth chapter contains the description of algorithms along with stages for testing the interpreter and the design of debug output. The stages and actions-are represented internally to the computer in tabular forms. For statement parsing working syntax equations are established. They serve as standards for the conversion of source statements into object pseudocodes. As the statement is parsed for legal form, pseudocodes for this statement are created. For pseudocode execution, pseudocodes are represented internally to the computer in tabular forms.
Date: May 1975
Creator: Chang, Min-Jye S.
System: The UNT Digital Library
A Design Approach for Digital Computer Peripheral Controllers, Case Study Design and Construction (open access)

A Design Approach for Digital Computer Peripheral Controllers, Case Study Design and Construction

The purpose of this project was to describe a novel design approach for a digital computer peripheral controller, then design and construct a case study controller. This document consists of three chapters and an appendix. Chapter II presents the design approach chosen; a variation to a design presented by Charles R. Richards in an article published in Electronics magazine. Richards' approach consists of a finite state machine circuitry controlling all the functions of a controller. The variation to Richards' approach consists of considering the various logically independent processes which a controller carries out and assigning control of each process to a separate finite state machine. The appendix contains the documentation of the design and construction of the controller.
Date: May 1976
Creator: Cabrera, A. L.
System: The UNT Digital Library
A Left-to-Right Parsing Algorithm for THIS Programming Language (open access)

A Left-to-Right Parsing Algorithm for THIS Programming Language

The subject of this investigation is a specific set of parsers known as LR parsers. Of primary interest is a LR parsing method developed by DeRemer which specifies a translation method which can be defined by a Deterministic Push-Down Automation (DPDA). The method of investigation was to apply DeRemer's parsing technique to a specific language known as THIS Programming Language (TPL). The syntax of TPL was redefined as state diagrams and these state diagrams were, in turn, encoded into two tables--a State-Action table and a Transition table. The tables were then incorporated into a PL/l adaptation of DeRemer's algorithm and tested against various TPL statements.
Date: May 1976
Creator: Hooker, David P.
System: The UNT Digital Library
Automated Testing of Interactive Systems (open access)

Automated Testing of Interactive Systems

Computer systems which interact with human users to collect, update or provide information are growing more complex. Additionally, users are demanding more thorough testing of all computer systems. Because of the complexity and thoroughness required, automation of interactive systems testing is desirable, especially for functional testing. Many currently available testing tools, like program proving, are impractical for testing large systems. The solution presented here is the development of an automated test system which simulates human users. This system incorporates a high-level programming language, ATLIS. ATLIS programs are compiled and interpretively executed. Programs are selected for execution by operator command, and failures are reported to the operator's console. An audit trail of all activity is provided. This solution provides improved efficiency and effectiveness over conventional testing methods.
Date: May 1977
Creator: Cartwright, Stephen C.
System: The UNT Digital Library
Computer Analysis of Amino Acid Chromatography (open access)

Computer Analysis of Amino Acid Chromatography

The problem with which this research was done was that of applying the IBM360 computer to the analysis of waveforms from a Beckman model 120C liquid chromatograph. Software to interpret these waveforms was written in the PLl language. For a control run, input to the computer consisted of a digital tape containing the raw results of the chromatograph run. Output consisted of several graphs and charts giving the results of the analysis. In addition, punched output was provided which gave the name of each amino acid, its elution time and color constant. These punched cards were then input to the computer as input to the experimental run, along with the raw data on the digital tape. From the known amounts of amino acids in the control run and the ratio of control to experimental peak area, the amino acids of the unknown were quantified. The resulting programs provided a complete and easy to use solution to the problem of chromatographic data analysis.
Date: May 1978
Creator: Hayes, Michael D.
System: The UNT Digital Library
A Top-Down Structured Programming Technique for Mini-Computers (open access)

A Top-Down Structured Programming Technique for Mini-Computers

This paper reviews numerous theoretical results on control structures and demonstrates their practical examples. This study deals with the design of run-time support routines by using top-down structured programming technique. A number of examples are given as illustration of this method. In conclusion, structured programming has proved to be an important methodology for systematic program design and development.
Date: May 1978
Creator: Wu, Chin-yi Robert
System: The UNT Digital Library
Notes on the SWTPC MP-N Calculator Interface and the Calc-1 Program (open access)

Notes on the SWTPC MP-N Calculator Interface and the Calc-1 Program

This interface was bought to perform floating-point arithmetic and for its function capabilities such as SIN, COS, and e^x. My application required an integer truncation function that is not performed by this calculator, so i wrote a small assembly language subroutine to do it. A potentially irritating problem is that the calculator chip does not automatically convert to scientific notation if the numbers become too big to display in floating point. The control program must keep track of the display mode.
Date: May 1979
Creator: Long, Daniel Paul
System: The UNT Digital Library
A Parallel Programming Language (open access)

A Parallel Programming Language

The problem of programming a parallel processor is discussed. Previous methods of programming a parallel processor, analyzing a program for parallel paths, and special language features are discussed. Graph theory is used to define the three basic programming constructs: choice, sequence, repetition. The concept of mechanized programming is expanded to allow for total separation of control and computational sections of a program. A definition of a language is presented which provides for this separation. A method for developing the program graph is discussed. The control graph and data graph are developed separately. The two graphs illustrate control and data predecessor relationships used in determining parallel elements of a program.
Date: May 1979
Creator: Cox, Richard D.
System: The UNT Digital Library
Software and Hardware Interface of a VOTRAX Terminal for the Fairchild F24 Computer (open access)

Software and Hardware Interface of a VOTRAX Terminal for the Fairchild F24 Computer

VOTRAX is a commercially available voice synthesizer for use with a digital computer. This thesis describes the design and implementation of a VOTRAX terminal for use with the Fairchild F24 computer. Chapters of the thesis consider the audio response technology, some characteristics of Phonetic English Speech, configuration of hardware, and describe the PHONO computer program which was developed. The last chapter discusses the advantages of the VOTRAX voice synthesizer and proposes a future version of the system with a time-sharing host computer.
Date: May 1979
Creator: Wu, Chun Hsiang
System: The UNT Digital Library
Defensive Programming (open access)

Defensive Programming

This research explores the concepts of defensive programming as currently defined in the literature. Then these concepts are extended and more explicitly defined. The relationship between defensive programming, as presented in this research, and current programming practices is discussed and several benefits are observed. Defensive programming appears to benefit the entire software life cycle. Four identifiable phases of the software development process are defined, and the relationship between these four phases and defensive programming is shown. In this research, defensive programming is defined as writing programs in such a way that during execution the program itself produces communication allowing the programmer and the user to observe its dynamic states accurately and critically. To accomplish this end, the use of defensive programming snap shots is presented as a software development tool.
Date: May 1980
Creator: Bailey, L. Mark
System: The UNT Digital Library
Machine Recognition of Hand-Send Morse Code Using the M6800 Microcomputer (open access)

Machine Recognition of Hand-Send Morse Code Using the M6800 Microcomputer

This research is the result of an effort to provide real-time machine recognition of hand-send Morse code through the use of the M6800 microcomputer. While the capability to recognize hand-send Morse code messages by machine has been demonstrated before on large scale special purpose computers, on minicomputers, and even on the M6800 microcomputer, the main contribution of this paper is to demonstrate it with relatively understandable hardware and software.
Date: May 1980
Creator: Firouzi, Hossein
System: The UNT Digital Library
Information Storage and Retrieval Systems (open access)

Information Storage and Retrieval Systems

This thesis describes the implementation of a general purpose personal information storage and retrieval system. Chapter one contains an introduction to information storage and retrieval. Chapter two contains a description of the features a useful personal information retrieval system should contain. This description forms the basis for the implementation of the personal information storage and retrieval system described in chapter three. The system is implemented in UCSD Pascal on an Apple II microcomputer.
Date: May 1983
Creator: Creech, Teresa Adams
System: The UNT Digital Library
A C Navigational System (open access)

A C Navigational System

The C Navigational System (CNS) is a proposed programming environment for the C programming language. The introduction covers the major influences of programming environments and the components of a programming environment. The system is designed to support the design, coding and maintenance phases of software development. CNS provides multiple views to both the source and documentation for a programming project. User-defined and system-defined links allow the source and documentation to be hierarchically searched. CNS also creates a history list and function interface for each function in a module. The final chapter compares CNS and several other programming environments (Microscope, Rn, Cedar, PECAN, and Marvel).
Date: May 1989
Creator: Hammerquist, James D. (James Daniel)
System: The UNT Digital Library
Inheritance Problems in Object-Oriented Database (open access)

Inheritance Problems in Object-Oriented Database

This research is concerned with inheritance as used in object-oriented database. More specifically, partial bi-directional inheritance among classes is examined. In partial inheritance, a class can inherit a proper subset of instance variables from another class. Two subclasses of the same superclass do not need to inherit the same proper subset of instance variables from their superclass. Bi-directional partial inheritance allows a class to inherit instance variables from its subclass. The prototype of an object-oriented database that supports both full and partial bi-directional inheritance among classes was developed on top of an existing relational database management system. The prototype was tested with two database applications. One database application needs full and partial inheritance. The second database application required bi-directional inheritance. The result of this testing suggests both advantages and disadvantages of partial bi-directional inheritance. Future areas of research are also suggested.
Date: May 1989
Creator: Auepanwiriyakul, Raweewan
System: The UNT Digital Library
Merlin Classifier System (open access)

Merlin Classifier System

There is a natural tendency for biological systems to change as their environments change. The fittest in the biological systems survive, adapt to their environment, and multiply while the weakest in the environment diminish. There have been attempts in computer science to model the processes of natural selection and survival which occur in biological systems in order to obtain more efficient and effective machine-learning algorithms. Genetic algorithms are the result of these attempts.
Date: May 1991
Creator: Pantermuehl, Brenda N.
System: The UNT Digital Library
DRVBLD: a UNIX Device Driver Builder (open access)

DRVBLD: a UNIX Device Driver Builder

New peripheral devices are being developed at an ever increasing rate. Before such accessories can be used in the UNIX environment (UNIX is a trademark of Bell Laboratories), they must be able to communicate with the operating system. This involves writing a device driver for each device. In order to do this, very detailed knowledge is required of both the device to be integrated and the version of UNIX to which it will be attached. The process is long, detailed and prone to subtle problems and errors. This paper presents a menu-driven utility designed to simplify and accelerate the design and implementation of UNIX device drivers by freeing developers from many of the implementation specific low-level details.
Date: May 1992
Creator: Cano, Agustin F.
System: The UNT Digital Library
A Mechanism for Facilitating Temporal Reasoning in Discrete Event Simulation (open access)

A Mechanism for Facilitating Temporal Reasoning in Discrete Event Simulation

This research establishes the feasibility and potential utility of a software mechanism which employs artificial intelligence techniques to enhance the capabilities of standard discrete event simulators. As background, current methods of integrating artificial intelligence with simulation and relevant research are briefly reviewed.
Date: May 1992
Creator: Legge, Gaynor W.
System: The UNT Digital Library
Using Extended Logic Programs to Formalize Commonsense Reasoning (open access)

Using Extended Logic Programs to Formalize Commonsense Reasoning

In this dissertation, we investigate how commonsense reasoning can be formalized by using extended logic programs. In this investigation, we first use extended logic programs to formalize inheritance hierarchies with exceptions by adopting McCarthy's simple abnormality formalism to express uncertain knowledge. In our representation, not only credulous reasoning can be performed but also the ambiguity-blocking inheritance and the ambiguity-propagating inheritance in skeptical reasoning are simulated. In response to the anomalous extension problem, we explore and discover that the intuition underlying commonsense reasoning is a kind of forward reasoning. The unidirectional nature of this reasoning is applied by many reformulations of the Yale shooting problem to exclude the undesired conclusion. We then identify defeasible conclusions in our representation based on the syntax of extended logic programs. A similar idea is also applied to other formalizations of commonsense reasoning to achieve such a purpose.
Date: May 1992
Creator: Horng, Wen-Bing
System: The UNT Digital Library
Using Normal Deduction Graphs in Common Sense Reasoning (open access)

Using Normal Deduction Graphs in Common Sense Reasoning

This investigation proposes a powerful formalization of common sense knowledge based on function-free normal deduction graphs (NDGs) which form a powerful tool for deriving Horn and non-Horn clauses without functions. Such formalization allows common sense reasoning since it has the ability to handle not only negative but also incomplete information.
Date: May 1992
Creator: Munoz, Ricardo A. (Ricardo Alberto)
System: The UNT Digital Library
Intrinsic and Extrinsic Adaptation in a Simulated Combat Environment (open access)

Intrinsic and Extrinsic Adaptation in a Simulated Combat Environment

Genetic algorithm and artificial life techniques are applied to the development of challenging and interesting opponents in a combat-based computer game. Computer simulations are carried out against an idealized human player to gather data on the effectiveness of the computer generated opponents.
Date: May 1995
Creator: Dombrowsky, Steven P. (Steven Paul)
System: The UNT Digital Library
A Theoretical Network Model and the Incremental Hypercube-Based Networks (open access)

A Theoretical Network Model and the Incremental Hypercube-Based Networks

The study of multicomputer interconnection networks is an important area of research in parallel processing. We introduce vertex-symmetric Hamming-group graphs as a model to design a wide variety of network topologies including the hypercube network.
Date: May 1995
Creator: Mao, Ai-sheng
System: The UNT Digital Library
Performance Study of Concurrent Search Trees and Hash Algorithms on Multiprocessors Systems (open access)

Performance Study of Concurrent Search Trees and Hash Algorithms on Multiprocessors Systems

This study examines the performance of concurrent algorithms for B-trees and linear hashing. B-trees are widely used as an access method for large, single key, database files, stored in lexicographic order on secondary storage devices. Linear hashing is a fast and reliable hash algorithm, suitable for accessing records stored unordered in buckets. This dissertation presents performance results on implementations of concurrent Bunk-tree and linear hashing algorithms, using lock-based, partitioned and distributed methods on the Sequent Symmetry shared memory multiprocessor system and on a network of distributed processors created with PVM (Parallel Virtual Machine) software. Initial experiments, which started with empty data structures, show good results for the partitioned implementations and lock-based linear hashing, but poor ones for lock-based Blink-trees. A subsequent test, which started with loaded data structures, shows similar results, but with much improved performances for locked Blink- trees. The data also highlighted the high cost of split operations, which reached up to 70% of the total insert time.
Date: May 1996
Creator: Demuynck, Marie-Anne
System: The UNT Digital Library
Rollback Reduction Techniques Through Load Balancing in Optimistic Parallel Discrete Event Simulation (open access)

Rollback Reduction Techniques Through Load Balancing in Optimistic Parallel Discrete Event Simulation

Discrete event simulation is an important tool for modeling and analysis. Some of the simulation applications such as telecommunication network performance, VLSI logic circuits design, battlefield simulation, require enormous amount of computing resources. One way to satisfy this demand for computing power is to decompose the simulation system into several logical processes (Ip) and run them concurrently. In any parallel discrete event simulation (PDES) system, the events are ordered according to their time of occurrence. In order for the simulation to be correct, this ordering has to be preserved. There are three approaches to maintain this ordering. In a conservative system, no lp executes an event unless it is certain that all events with earlier time-stamps have been executed. Such systems are prone to deadlock. In an optimistic system on the other hand, simulation progresses disregarding this ordering and saves the system states regularly. Whenever a causality violation is detected, the system rolls back to a state saved earlier and restarts processing after correcting the error. There is another approach in which all the lps participate in the computation of a safe time-window and all events with time-stamps within this window are processed concurrently. In optimistic simulation systems, there is …
Date: May 1996
Creator: Sarkar, Falguni
System: The UNT Digital Library
Symplectic Integration of Nonseparable Hamiltonian Systems (open access)

Symplectic Integration of Nonseparable Hamiltonian Systems

Numerical methods are usually necessary in solving Hamiltonian systems since there is often no closed-form solution. By utilizing a general property of Hamiltonians, namely the symplectic property, all of the qualities of the system may be preserved for indefinitely long integration times because all of the integral (Poincare) invariants are conserved. This allows for more reliable results and frequently leads to significantly shorter execution times as compared to conventional methods. The resonant triad Hamiltonian with one degree of freedom will be focused upon for most of the numerical tests because of its difficult nature and, moreover, analytical results exist whereby useful comparisons can be made.
Date: May 1996
Creator: Curry, David M. (David Mason)
System: The UNT Digital Library