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An Application Of Artificial Intelligence Technology Within The Standard Base Supply System, Richard G. Nelson Sep 1991

An Application Of Artificial Intelligence Technology Within The Standard Base Supply System, Richard G. Nelson

Theses and Dissertations

This thesis investigated the feasibility of applying artificial intelligence technology within the Standard Base Supply System (SBSS). With assembly endless reductions in manpower authorizations within the SBSS and the potential for a continued loss of expert knowledge, the use of knowledge-based system (KBSs) was examined to determine if these systems could alleviate this of manpower. Literature related to the fields of artificial intelligence, expert systems, and KBSs was traced, yielding a methodology for identifying candidate problems, and for the development, verification, and validation of prototype KBSs. This methodology was then employed within the research, culminating in the creation, verification, and …


A Topological Model For Parallel Algorithm Design, Jeffrey A. Simmers Sep 1991

A Topological Model For Parallel Algorithm Design, Jeffrey A. Simmers

Theses and Dissertations

This research demonstrates that formal, mathematical analysis in theoretical computer science can be recast in terms of the topology of complete metric spaces, and also presents a methodical technique for developing formal specifications. This effort shows that the topology of complete metric spaces provides a tool that can be used to both recreate major results about computational models and also to develop new results about these models. Using the two computational models CSP and UNITY, this effort shows that the required mathematics needed to support this alternative to the traditional analysis of computational models can be readily supported by a …


Visual Knowledge Query Language As A Front-End To Relational Systems, Keng Siau, Kok Phuang Tan, Hock Chuan Chan Sep 1991

Visual Knowledge Query Language As A Front-End To Relational Systems, Keng Siau, Kok Phuang Tan, Hock Chuan Chan

Research Collection School Of Computing and Information Systems

Relational query languages like SQL and QUEL require the users to understand the complex database structure. This is a burden on end users, especially novice end users who access the database on a casual and infrequent basis. To alleviate the need to know the logical database organization, this paper proposes the use of a semantic data model, known as the Enhanced Entity-Relationship (EER) model, as a front-end to the relational systems. A formal, high-level Visual Knowledge Query Language (VKQL) has also been designed for this interface. This language provides for knowledge abstraction as the user communicates only domain knowledge with …


Visual Knowledge Query Language As A Front-End To Relational Systems, Keng Siau, Kok Phuang Tan, Hock Chuan Chan Sep 1991

Visual Knowledge Query Language As A Front-End To Relational Systems, Keng Siau, Kok Phuang Tan, Hock Chuan Chan

Research Collection School Of Computing and Information Systems

Relational query languages like SQL and QUEL require the users to understand the complex database structure. This is a burden on end users, especially novice end users who access the database on a casual and infrequent basis. To alleviate the need to know the logical database organization, this paper proposes the use of a semantic data model, known as the Enhanced Entity-Relationship (EER) model, as a front-end to the relational systems. A formal, high-level Visual Knowledge Query Language (VKQL) has also been designed for this interface. This language provides for knowledge abstraction as the user communicates only domain knowledge with …


Computer Viruses And Ethics, Eugene H. Spafford Aug 1991

Computer Viruses And Ethics, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


On Surface Design With Implicit Algebraic Surfaces (Ph.D. Thesis), Insung Ihm Aug 1991

On Surface Design With Implicit Algebraic Surfaces (Ph.D. Thesis), Insung Ihm

Department of Computer Science Technical Reports

No abstract provided.


Formal Methods Of Real-Time Systems, Su-Mei Tsai, Bruce M. Mcmillin Aug 1991

Formal Methods Of Real-Time Systems, Su-Mei Tsai, Bruce M. Mcmillin

Computer Science Technical Reports

Formal aid in specification and verification techniques have become an accepted approach to achieving reliable software for life-critical real-time systems, in which testing may be impossible or too dangerous, since the real inputs to the systems come from the real world. Modelling, assertion languages, and proof systems are three major components that are employed to accomplish the confidence of safe real-time environments. This paper examines these currently available techniques that are used for safety analysis of real-time systems.


An Improved Algorithm For Neural Network Classification Of Imbalanced Training Sets, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Aug 1991

An Improved Algorithm For Neural Network Classification Of Imbalanced Training Sets, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

In this paper, we analyze the reason for the slow rate of convergence of net output error when using the backpropagation algorithm to train neural networks for a two-class problems in which the numbers of exemplars for the two classes differ greatly. This occurs because the negative gradient vector computed by backpropagation for an imbalanced training set does not point initially in a downhill direction for the class with the smaller number of exemplars. Consequently, in the initial iteration, the net error for the exemplars in this class increases significantly. The subsequent rate of convergence of the net error is …


Semi-Distributed Load Balancing For Massively Parallel Multicomputer Systems, Ishfaq Ahmad, Arif Ghafoor Aug 1991

Semi-Distributed Load Balancing For Massively Parallel Multicomputer Systems, Ishfaq Ahmad, Arif Ghafoor

Electrical Engineering and Computer Science - Technical Reports

This paper presents a semi-distributed approach, for load balancing in large parallel and distributed systems, which is different from the conventional centralized and fully distributed approaches. The proposed strategy uses a two-level hierarchical control by partitioning the interconnection structure of a distributed or multiprocessor system into independent symmetric regions (spheres) centered at some control points. The central points, called schedulers, optimally schedule tasks within their spheres and maintain state information with low overhead. We consider interconnection structures belonging to a number of families of distance transitive graphs for evaluation, and using their algebraic characteristics, show that identification of spheres and …


Collision Detection And Analysis In A Physically Based Simulation, William J. Bouma, George Vanĕček Jul 1991

Collision Detection And Analysis In A Physically Based Simulation, William J. Bouma, George Vanĕček

Department of Computer Science Technical Reports

No abstract provided.


Formal Generation Of Executable Assertions For A Fault-Tolerant Parallel Bitonic Sort, Hanan Lutfiyya, Bruce M. Mcmillin Jul 1991

Formal Generation Of Executable Assertions For A Fault-Tolerant Parallel Bitonic Sort, Hanan Lutfiyya, Bruce M. Mcmillin

Computer Science Technical Reports

No abstract provided.


The Complexity Of Local Stratification, Peter Cholak, Howard A. Blair Jul 1991

The Complexity Of Local Stratification, Peter Cholak, Howard A. Blair

Electrical Engineering and Computer Science - Technical Reports

The class of locally stratified logic programs is shown to be Π11-complete by the construction of a reducibility of the class of infinitely branching nondeterministic finite register machines.nondeterministic finite register machines.


Constructing Real-Time Systems From Temporal I/O Automata, J. F. Peters Iii, S. Ramanna Jul 1991

Constructing Real-Time Systems From Temporal I/O Automata, J. F. Peters Iii, S. Ramanna

Electrical Engineering and Computer Science - Technical Reports

A new class of communicating automata called Temporal Input/Output Automata (TAi/os) is introduced. A TAi/o is a predicate automaton used to specify real-time systems. The specification provided by a TAi/o includes state predicates with proof expressions and abstract program syntax as attributes. An abstract program is extracted during a constructive proof of the specification using the proof expressions. A TAi/o specification also includes hard, real-time constraints on program behavior. The predictability of deterministic, temporally complete TAi/o is investigated. The formulation of real-time system transductions and transduction rules for TAi/os in explicit clock temporal logic is given. An illustration of the …


Converting Binary Thresholds Networks Into Equivalent Symmetric Networks, Gadi Pinkas Jul 1991

Converting Binary Thresholds Networks Into Equivalent Symmetric Networks, Gadi Pinkas

All Computer Science and Engineering Research

We give algorithms to convert any network of binary threshold units (that does not oscillate) into an equivalent network with symmetric weight matrix (like Hopfield networks [Hopfield 82] or Boltzmann machines [Hinton, Sejnowski 88]). The motivation for the transformation is dual: a) to demonstrate the expressive power of symmetric networks; i.e. binary threshold networks (that do not oscillate) are subsumed in the energy minimization paradigm; 2) to use network modules (developed for the spreading activation paradigm for example), within the energy minimization paradigm. Thus optimization [Tank, Hopfield 88] and approximation of hard problems can be combined with efficient modules, that …


An Access Protection Solution For Heavy Load Unfairness In Dqdb, Lakshmana N. Kumar, Andreas D. Bovopoulos Jul 1991

An Access Protection Solution For Heavy Load Unfairness In Dqdb, Lakshmana N. Kumar, Andreas D. Bovopoulos

All Computer Science and Engineering Research

This paper discusses the unfairness issue arising in a 802.6 DQDB network at high loads-- when the traffic demand to a bus exceeds the capacity of that bus. As per the 802.6 protocol, at heavy loads, the end nodes along a bus experience longer delays than the other nodes. The origin and remedy of this heavy load unfairness is discussed. An access control scheme is proposed as a solution. The comparison of the proposed scheme with 802.6 protocol is presented. The simulation results and performance characteristics are discussed under several types of loads. With symmetric load conditions under the proposed …


The Spectrum Simulation System: A Formal Approach To Distributed Algorithm Development Tools, Kenneth J. Goldman Jul 1991

The Spectrum Simulation System: A Formal Approach To Distributed Algorithm Development Tools, Kenneth J. Goldman

All Computer Science and Engineering Research

We present the Spectrum Simulation System, a new research tool for the design and study of distributed algorithms. Based on the formal Input/Output Automation model of Lynch and Tuttle, Spectrum allows one to express distributed algorithms as collections of I/O automata and simulate them directly in terms of the semantics of that model. This permits integration of algorithm specification, design, debugging, analysis, and proof of correctness within a single formal framework that is natural for describing distributed algorithms. Spectrum provides a language for expressing algorithms as I/O automata, a simulator for generating algorithm executions, and a graphics interface for constructing …


Composition, Superposition, And Encapsulation In The Formal Specification Of Distributed Systems, Kenneth J. Goldman Jul 1991

Composition, Superposition, And Encapsulation In The Formal Specification Of Distributed Systems, Kenneth J. Goldman

All Computer Science and Engineering Research

Composition, superposition, and encapsulation are important techniques that work well together for designing large distributed software systems. Composition is a symmetric operator that allows system components to communicate with each other across module boundaries. Superposition is an asymmetric relationship that allows one system component to observe the state of another. Encapsulation is the ability to define the reason about the behavior of a module in terms of a well-defined boundary between that module and its environment, while hiding the internal operations of that module. In this paper, the I/O automation model of Lynch and Tuttle is extended to permit superposition …


Rapid Display Of Radiographic Images, Jerome R. Cox Jr., Stephen M. Moore, Robert A. Whitman, G. James Blaine, R. Gilbert Jost, L. Magnus Karlsson, Thomas L. Monsees, Gregory L. Hansen, Timothy C. David Jul 1991

Rapid Display Of Radiographic Images, Jerome R. Cox Jr., Stephen M. Moore, Robert A. Whitman, G. James Blaine, R. Gilbert Jost, L. Magnus Karlsson, Thomas L. Monsees, Gregory L. Hansen, Timothy C. David

All Computer Science and Engineering Research

The requirements for the rapid display of radiographic images exceed the capabilities of widely available display, computer and communication technologies. Computed radiography captures data with a resolution of about four megapixels. Large format displays are available that can present over four megapixels. One megapixel displays are practical for use in combination with large format displays and in areas where the viewing task does not require primary diagnosis. This paper describes an electronic radiology system that approximates the highest quality systems, but through the use of several interesting techniques allows the possibility of its widespread installation throughout hospitals. The techniques uses …


Fast Parallel Algorithms For Basic Problems, Zhaofang Wen Jul 1991

Fast Parallel Algorithms For Basic Problems, Zhaofang Wen

Computer Science Theses & Dissertations

Parallel processing is one of the most active research areas these days. We are interested in one aspect of parallel processing, i.e. the design and analysis of parallel algorithms. Here, we focus on non-numerical parallel algorithms for basic combinatorial problems, such as data structures, selection, searching, merging and sorting. The purposes of studying these types of problems are to obtain basic building blocks which will be useful in solving complex problems, and to develop fundamental algorithmic techniques.

In this thesis, we study the following problems: priority queues, multiple search and multiple selection, and reconstruction of a binary tree from its …


A Robust Approach To Human-Computer Interface Design Using The Taguchi Method, Billie Mitchell Reed Jul 1991

A Robust Approach To Human-Computer Interface Design Using The Taguchi Method, Billie Mitchell Reed

Engineering Management & Systems Engineering Theses & Dissertations

The application of Dr. Genichi Taguchi's approach for design optimization, called Robust Design, to the design of human-computer interface software is investigated. The Taguchi Method is used to select a near optimum set of interface design alternatives to improve user acceptance of the resulting interface software product with minimum sensitivity to uncontrollable noise caused by human behavioral characteristics.

Design alternatives for interaction with personal micro-computers are identified. Several important and representative alternatives are chosen as design parameters for the Taguchi matrix experiment. A noise field with three human behavioral characteristics as noise factors were chosen as a representative noise array. …


Philco: Some Recollections Of The Philco Transac S-2000, Saul Rosen Jun 1991

Philco: Some Recollections Of The Philco Transac S-2000, Saul Rosen

Department of Computer Science Technical Reports

No abstract provided.


Negotiating And Supporting Interdependent Data In Very Large Federated Database Systems, Ahmed K. Elmagarmid, James G. Mullen Jun 1991

Negotiating And Supporting Interdependent Data In Very Large Federated Database Systems, Ahmed K. Elmagarmid, James G. Mullen

Department of Computer Science Technical Reports

No abstract provided.


Design And Implementation Of A Distributed System With Dynamic Resource Allocation Based Upon Bidding Schemes, Dan C. Marinescu, Kenneth Wenstrup, Patrick Davis Jun 1991

Design And Implementation Of A Distributed System With Dynamic Resource Allocation Based Upon Bidding Schemes, Dan C. Marinescu, Kenneth Wenstrup, Patrick Davis

Department of Computer Science Technical Reports

No abstract provided.


Smili-Visualization Of Asynchronous Massively Parallel Programs, Rashi Khanna, Bruce M. Mcmillin Jun 1991

Smili-Visualization Of Asynchronous Massively Parallel Programs, Rashi Khanna, Bruce M. Mcmillin

Computer Science Technical Reports

A visualization model has been developed to analyse the performance of a massively parallel algorithm. Most visualization tools that have been developed so far for performance analysis are based generally on individual processor information and communication patterns (eg. processor load, message traffic etc.). These tools, however, are inadequate for massively parallel computations. It is difficult to comprehend the visual information for many processors. The model, SMil...l (Scientific visualization in Multicomputing for Interpretation of Large amounts of Information), addresses this problem by using abstract representations to attain a composite picture which gives better insight to the behavior of the algorithm. Chernoff's …


Comparison Of Three Axiomatic Systems For Csp, Hanan Lutfiyya, Bruce M. Mcmillin Jun 1991

Comparison Of Three Axiomatic Systems For Csp, Hanan Lutfiyya, Bruce M. Mcmillin

Computer Science Technical Reports

Currently software engineering practices use relatively few formal methods. However, formal methods can be used to find errors earlier in the software cycle and hence reduce software cost. One useful formal method is program verification. The axiomatic approach to program verification uses assertions to characterize properties of program variables and relationships between them at various stages of program execution. In order to verify these assertions, axioms or inference rules are needed for each statement as well as some statement-independent inference rules. The message passing and nondeterminism of a distributed programming language present special difficulties. This paper examines and compares three …


Smili-Visualization Of Asynchronous Massively Parallel Programs, Rashi Khanna, Bruce M. Mcmillin Jun 1991

Smili-Visualization Of Asynchronous Massively Parallel Programs, Rashi Khanna, Bruce M. Mcmillin

Computer Science Technical Reports

A visualization model has been developed to analyse the performance of a massively parallel algorithm. Most visualization tools that have been developed so far for performance analysis are based generally on individual processor information and communication patterns (eg. processor load, message traffic etc.). These tools, however, are inadequate for massively parallel computations. It is difficult to comprehend the visual information for many processors. The model, SMil...l (Scientific visualization in Multicomputing for Interpretation of Large amounts of Information), addresses this problem by using abstract representations to attain a composite picture which gives better insight to the behavior of the algorithm. Chernoff's …


Comparison Of Three Axiomatic Systems For Csp, Hanan Lutfiyya, Bruce M. Mcmillin Jun 1991

Comparison Of Three Axiomatic Systems For Csp, Hanan Lutfiyya, Bruce M. Mcmillin

Computer Science Technical Reports

Currently software engineering practices use relatively few formal methods. However, formal methods can be used to find errors earlier in the software cycle and hence reduce software cost. One useful formal method is program verification. The axiomatic approach to program verification uses assertions to characterize properties of program variables and relationships between them at various stages of program execution. In order to verify these assertions, axioms or inference rules are needed for each statement as well as some statement-independent inference rules. The message passing and nondeterminism of a distributed programming language present special difficulties. This paper examines and compares three …


A Sixteen-Valued Algorithm For Test Generation In Combinational Circuits, Akhtar Uz Zaman, M. Ali, Carlos R.P. Hartmann Jun 1991

A Sixteen-Valued Algorithm For Test Generation In Combinational Circuits, Akhtar Uz Zaman, M. Ali, Carlos R.P. Hartmann

Electrical Engineering and Computer Science - Technical Reports

A 16-valued logic system for testing combinational circuits is presented. This logic system has been used to develop SIMPLE, an efficient test generation algorithm for single stuck-at faults. The proposed scheme for testing stuck-at faults is based on imposing all the constraints that must be satisfied in order to sensitize a path from a fault site to a primary output. Consequently all deterministic implications are fully considered prior to the enumeration process. The resulting ability to identify inconsistencies prior to enumeration improves the possibility of quicker identification of redundant faults. In order to prune the search space we have introduced …


The Difficulty Of Random Attribute Noise, Sally A. Goldman, Robert H. Sloan Jun 1991

The Difficulty Of Random Attribute Noise, Sally A. Goldman, Robert H. Sloan

All Computer Science and Engineering Research

This paper studies the robustness of pac learning algorithms when the instance space is {0,1}n, and the examples are corrupted by purely random noise affecting only the instances (and not the labels). In the past, conflicting results on this subject have been obtained-- the "best agreement" rule can only tolerate small amounts of noise, yet in some cases large amounts of noise can be tolerated. We show the truth lies somewhere between the two alternatives. For uniform attribute noise, in which each attribute is flipped independently at random with the same probability, we present an algorithm that pac learns monomial …


Dna Mapping Algorithms: Abstract Data Types - Concepts And Implementation, Will Gillett, Liz Hanks Jun 1991

Dna Mapping Algorithms: Abstract Data Types - Concepts And Implementation, Will Gillett, Liz Hanks

All Computer Science and Engineering Research

The conceptual aspects of and the implementation details of a set of self-identifying abstract data types (ADT) are described. Each of the ADTs constitutes a specific class of object, upon which a set of well-defined access functions is available. The intent of these ADTs is to supply a paradigm in which a class of object is available for manipulation, but in which the underlying implementation is hidden from the application programmer. Specific ADTs are the described in some detail. The tagged architecture used to achieve the self-identifying property of the ADTs is presented, and a set of required system-backbone access …