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Adaptive Histogram Equalization, A Parallel Implementation, Charles W. Kurak Jr. Jan 1990

Adaptive Histogram Equalization, A Parallel Implementation, Charles W. Kurak Jr.

UNF Graduate Theses and Dissertations

Adaptive Histogram Equalization (AHE) has been recognized as a valid method of contrast enhancement. The main advantage of AHE is that it can provide better contrast in local areas than that achievable utilizing traditional histogram equalization methods. Whereas traditional methods consider the entire image, AHE utilizes a local contextual region.

However, AHE is computationally expensive, and therefore time-consuming. In this work two areas of computer science, image processing and parallel processing, are combined to produce an efficient algorithm. In particular, the AHE algorithm is implemented with a Multiple-Instruction-Multiple-Data (MIMD) parallel architecture. It is proposed that, as MIMD machines become more …


Human-Machine Interface For Tactical Air Traffic Control Communications, Alan Mastin Jan 1990

Human-Machine Interface For Tactical Air Traffic Control Communications, Alan Mastin

UNF Graduate Theses and Dissertations

This thesis proposes the design for a prototype device that would be used by Air Traffic Controllers in the radar environment to input tactical Air Traffic Control (ATC) instructions to be sent to aircraft via the Mode S digital data link network. The purpose of the device is to reduce the time required to issue instructions and to eliminate misunderstandings that occur when instructions are issued over voice transmission frequencies. The purpose of this thesis was to develop the device in the most ergonomically suited manner based on the air traffic controller's communications requirements. Digital communications systems include both airborne …


Educational Software Development Using Hypertext And Expert System Software Concepts, Siripong Malasri, Roger R. Easson Jan 1990

Educational Software Development Using Hypertext And Expert System Software Concepts, Siripong Malasri, Roger R. Easson

Journal of the Arkansas Academy of Science

This paper presents two computer software concepts: hypertext and expert systems; which are useful for educational software development. Good educational software enhances the learning process and offers opportunities for faculty to provide additional materials for independent studies, which would otherwise be impossible, due to the limited time and incredible growing rate of technological progress. The hypertext concept offers the students a non-linear learning style, while the expert system concept provides explanation facilities for students to probe the logic of the systems. Both approaches are extremely useful for educational software. With the proper tools, the courseware can be implemented easily and …


Impact Of Microprocessor Protected Mode Programming On Undergraduate Education N Engineering Technology, Robert L. Douglas Jan 1990

Impact Of Microprocessor Protected Mode Programming On Undergraduate Education N Engineering Technology, Robert L. Douglas

Journal of the Arkansas Academy of Science

No abstract provided.


Performance Improvements For Fddi And Csma/Cd Protocols, David Earl Game Jan 1990

Performance Improvements For Fddi And Csma/Cd Protocols, David Earl Game

Computer Science Theses & Dissertations

The High-Performance Computing Initiative from the White House Office of Science and Technology Policy has defined 20 major challenges in science and engineering which are dependent on the solutions to a number of high-performance computing problems. One of the major areas of focus of this initiative is the development of gigabit rate networks to be used in environments such as the space station or a National Research and Educational Network (NREN).

The strategy here is to use existing network designs as building blocks for achieving higher rates, with the ultimate goal being a gigabit rate network. Two strategies which contribute …


Design Of A Dynamically Reconfigurable, Integrated, Parallel Vision System, Ashok K. Samal Jan 1990

Design Of A Dynamically Reconfigurable, Integrated, Parallel Vision System, Ashok K. Samal

School of Computing: Conference and Workshop Papers

Multiprocessors can be used to speed up the process of object recognition. Building a parallel vision system is a two step process: (a) design and implement parallel algorithms for individual operations, and (b) integrate them into a coherent system. So far the emphasis has been on the first step. The second step has not received enough attention. A framework for building a parallel vision system is presented here. The necessary and desirable features of such a system have been identified. An initial design which incorporates these features is also given.


A Statistical Theory Of Digital Circuit Testability, Sharad C. Seth, Vishwani D. Agrawal, Hassan Farhat Jan 1990

A Statistical Theory Of Digital Circuit Testability, Sharad C. Seth, Vishwani D. Agrawal, Hassan Farhat

School of Computing: Faculty Publications

When test vectors are applied to a circuit, the fault coverage increases. The rate of increase, however, could be circuit dependent. A relation between the average fault coverage and circuit testability is developed in this paper. The statistical formulation allows computation of coverage for deterministic and random vectors. We discuss the following applications of this analysis: determination of circuit testability from fault simulation, coverage prediction from testability analysis, prediction of test length, and test generation by fault sampling.


High-Level Microprogramming: An Optimising C Compiler For A Processing Element Of A Cad Accelerator, Paul Kenyon, Prathima Agrawal, Sharad C. Seth Jan 1990

High-Level Microprogramming: An Optimising C Compiler For A Processing Element Of A Cad Accelerator, Paul Kenyon, Prathima Agrawal, Sharad C. Seth

School of Computing: Faculty Publications

The development of a high-level language compiler for a micro-programmable processing element (PE) in the MARS multicomputer is described. MARS, an MIMD message passing machine, was designed to speed up VLSI CAD and similar other non-numerical applications. The need for sup port of a high-level language at the PE level of a multicomputer is considered, and the choice of C as an appropriate programming language is justified. Special features found in VLSI processors are examined along with compiler support for them.

Conventional re-targetable compiler techniques are shown to be inadequate for the highly concurrent micro-programmable PE. These techniques must be …


An Experimental Study On Reject Ratio Prediction For Vlsl Circuits: Kokomo Revisited, Dharam Vir Das, Sharad C. Seth, Paul T. Wagner, John Anderson, Vishwani Agrawal Jan 1990

An Experimental Study On Reject Ratio Prediction For Vlsl Circuits: Kokomo Revisited, Dharam Vir Das, Sharad C. Seth, Paul T. Wagner, John Anderson, Vishwani Agrawal

School of Computing: Faculty Publications

Assuring product quality is becoming increasingly more important for the semiconductor chip manufacturers. The reject ratio (defect level) provides a simple and accurate measure of a product's quality. However, measuring the reject ratio of tested chips is often not feasible or accurate. Statistical techniques for reject ratio prediction provide a possible way out of this dilemma. In this paper, we report on an experiment to verify the accuracy of reject ratio predictions by the available approaches. The data collection effort includes instrumenting the wafer probe test to obtain chip failures as a function of applied vectors and running a fault …


Measurement Of The C+ Decay-Asymmetry Parameter, Avery, P.; Et Al., M. Thulasidas Jan 1990

Measurement Of The C+ Decay-Asymmetry Parameter, Avery, P.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

We report a measurement of polarization in the two-body decay c+, in nonresonant e+e- interactions from data taken with the CLEO detector. Using these data we have determined the parity-violating asymmetry decay parameter c to be -1.0-0.0+0.4. We see no evidence for significant c+ polarization.


Observation Of B-Meson Semileptonic Decays To Noncharmed Final States, Fulton, R.; Et Al., M. Thulasidas Jan 1990

Observation Of B-Meson Semileptonic Decays To Noncharmed Final States, Fulton, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


Observation Of Iv(4=S) Decays Into Non-=Bba Final States Containing I Mesons, Alexander, J.; Et Al., M. Thulasidas Jan 1990

Observation Of Iv(4=S) Decays Into Non-=Bba Final States Containing I Mesons, Alexander, J.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

We report on the observation of ; mesons from T(4S) decays which are too energetic to come from 8 mesons. These events provide evidence for non-88 decays of the T (4S). The measured rate is B(T(4S)+fX)=0.22•0.06•0.041 for ; momentum above 2 GeV/c.


An Expert System To Convert Knowledge-Based Geological Engineering Systems Into Fortran, Ralph W. Wilkerson, Jill J. Cress Jan 1990

An Expert System To Convert Knowledge-Based Geological Engineering Systems Into Fortran, Ralph W. Wilkerson, Jill J. Cress

Computer Science Faculty Research & Creative Works

A knowledge-based geographic information system (KBGIS) for geological engineering map (GEM) production was developed in GoldWorks, an expert system development shell. Using this shell, the geological engineer is able to develop a rule base for a particular application that results in a valid GEM. However, this implementation failed as a practical production system due to the excessive execution time required to produce a GEM. To solve this problem, a conversion expert system was developed which accepted, as input, a KBGIS and produced, as output, the equivalent Fortran code. Two major objectives are accomplished as a result of this system: GEN …


Experimentation With Large-Grained Parallelism Using Local Area Networks, Ralph W. Wilkerson, Douglas E. Meyer Jan 1990

Experimentation With Large-Grained Parallelism Using Local Area Networks, Ralph W. Wilkerson, Douglas E. Meyer

Computer Science Faculty Research & Creative Works

HIGHLAND, a distributed-memory parallel processing environment for heterogeneous local area networks, has been developed. Designed as both a teaching and a research tool, its purpose is to provide an effective mechanism by which a number of networked UNIX workstations, dissimilar in both vendor and performance, can be directly manipulated as a single, unified, multiprocessing system. Utilizing the MIT X-windows environment, HIGHLAND supports a highly interactive graphical interface through which a programmer can create, modify, and control complex systems of communicating processes


Highland: A Graph-Based Parallel Processing Environment For Heterogeneous Local Area Networks, Ralph W. Wilkerson, Douglas E. Meyer Jan 1990

Highland: A Graph-Based Parallel Processing Environment For Heterogeneous Local Area Networks, Ralph W. Wilkerson, Douglas E. Meyer

Computer Science Faculty Research & Creative Works

No abstract provided.


Role Of Term Symmetry In E-Completion Procedures, Ralph W. Wilkerson, Blayne E. Mayfield Jan 1990

Role Of Term Symmetry In E-Completion Procedures, Ralph W. Wilkerson, Blayne E. Mayfield

Computer Science Faculty Research & Creative Works

No abstract provided.


Experimental Comparison Of Bidding And Drafting Load Sharing Protocols, Andrew Ross, Bruce M. Mcmillin Jan 1990

Experimental Comparison Of Bidding And Drafting Load Sharing Protocols, Andrew Ross, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

In recent years, a dramatic rise in the number of personal workstations interconnected via local area networks has occurred in the workplace. These can be organized as distributed computing systems. The combined computing power of these systems are often greater than mainframes of a decade ago, and usually less expensive. There is a growing interest in harnessing this often-underutilized power. Researchers are focusing their attention on remote execution of processes as one solution. An additional topic of research is to balance a workload among a series of computers. Remote execution is made possible because the distributed operating system provides migration …


Computational Intelligence In Cad/Cam Applications, Chaman Sabharwal, Thomas G. Melson, Martin D. Fraser Jan 1990

Computational Intelligence In Cad/Cam Applications, Chaman Sabharwal, Thomas G. Melson, Martin D. Fraser

Computer Science Faculty Research & Creative Works

This paper presents a fundamental, direct, and powerful approach to the surface/surface intersection problem in CAD/CAM applications. The algorithm is designed and implemented in three steps: a) Preprocessing- locate the potentially intersecting sections of the surfaces and decompose the surfaces into surface elements within specified flatness tolerance; b) Intersection- decompose the possibly intersecting pairs of surface elements into continuous surface triangulations to find the approximate intersections between the pairs of surface elements; c) Postprocessing-assemble the intersection primitives into curves of intersection, refine the accuracy of computed intersection points, and compact the intersection curves. This surface/surface intersection algorithm is applicable to …


Distributed Evaluation Of An Iterative Function For All Object Pairs On A Simd Hypercube, Fikret Erçal Jan 1990

Distributed Evaluation Of An Iterative Function For All Object Pairs On A Simd Hypercube, Fikret Erçal

Computer Science Faculty Research & Creative Works

An efficient distributed algorithm for evaluating an iterative function on all pairwise combinations of C objects on an SIMD hypercube is presented. The algorithm achieves uniform load distribution and minimal, completely local interprocessor communication.


Pipelining Data Compression Algorithms, R. L. Bailey, R. Mukkamala Jan 1990

Pipelining Data Compression Algorithms, R. L. Bailey, R. Mukkamala

Computer Science Faculty Publications

Many different data compression techniques currently exist. Each has its own advantages and disadvantages. Combining (pipelining) multiple data compression techniques could achieve better compression rates than is possible with either technique individually. This paper proposes a pipelining technique and investigates the characteristics of two example pipelining algorithms. Their performance is compared with other well-known compression techniques.


Wings And Perfect Graphs, Stephan Olariu Jan 1990

Wings And Perfect Graphs, Stephan Olariu

Computer Science Faculty Publications

An edge uv of a graph G is called a wing if there exists a chordless path with vertices u, v, x, y and edges uv, vx, xy. The wing-graph W(G) of a graph G is a graph having the same vertex set as G; uv is an edge in W(G) if and only if uv is a wing in G. A graph G is saturated if G is isomorphic to W(G). A star-cutset in a graph G is a non-empty set of …


Performance Analysis Of A Distributed File System, Meenakshi Mukhopadhyay Jan 1990

Performance Analysis Of A Distributed File System, Meenakshi Mukhopadhyay

Dissertations and Theses

An important design goal of a distributed file system, a component of many distributed systems, is to provide UNIX file access semantics, e.g., the result of any write system call is visible by all processes as soon as the call completes. In a distributed environment, these semantics are difficult to implement because processes on different machines do not share kernel cache and data structures. Strong data consistency guarantees may be provided only at the expense of performance.

This work investigates the time costs paid by AFS 3.0, which uses a callback mechanism to provide consistency guarantees, and those paid by …


Efficient Schemes To Evaluate Transaction Performance In Distributed Database Systems, R. Mukkamala, S. C. Bruell Jan 1990

Efficient Schemes To Evaluate Transaction Performance In Distributed Database Systems, R. Mukkamala, S. C. Bruell

Computer Science Faculty Publications

Database designers and researchers often need efficient schemes to evaluate transaction performance. In this paper, we chose two important performance measures: the average number of nodes accessed and the average number of data items accessed per node by a transaction in a distributed database system. We derive analytical expressions to evaluate these metrics. For general applicability, we consider partially replicated distributed database systems. Our first set of analytic results are closed-form expressions for these two measures. These are based on some fairly restrictive simplifying assumptions. When these assumptions are relaxed, no closed-form expressions exist for these averages. Hence, we develop …


Digital Image Processing Using Mathematical Morphology, Andrew Mehnert Jan 1990

Digital Image Processing Using Mathematical Morphology, Andrew Mehnert

Theses : Honours

This dissertation is a natural extension of my undergraduate research project entitled, "Digital Image Processing”. Whilst my undergraduate project dealt with a number of classical digital image filtering techniques such as spatial convolution and frequency domain filtering via the Fourier transform, this dissertation focuses on an alternative approach employing Mathematical Morphology. In contrast to classical filtering techniques, which often geometrically distort the original image, morphological operations, used sensibly, essentially preserve shape and geometry. Mathematical morphology therefore lends itself to image processing applications requiring the identification of objects and object features within an image. Herein basic morphological operations are developed, firstly …


Exclusive And Inclusive Decays Of B Mesons Into Ds Mesons, D. Bortoletto, Manoj Thulasidas Jan 1990

Exclusive And Inclusive Decays Of B Mesons Into Ds Mesons, D. Bortoletto, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

We have studied the production of Ds mesons in the decays of B mesons at the Υ(4S) resonance. We report on the first observation of exclusive B-meson decays B->Ds−D*+, B→Ds−D+, and B→Ds−D0. We also present a new measurement of the branching ratio and the momentum spectrum for the inclusive decay B→DsX.


Trellis-Coded Multidimensional Phase Modulation, S. S. Pietrobon, Robert H. Deng Jan 1990

Trellis-Coded Multidimensional Phase Modulation, S. S. Pietrobon, Robert H. Deng

Research Collection School Of Computing and Information Systems

A 2L-dimensional multiple phase-shift keyed (L×MPSK) signal set is obtained by forming the Cartesian product of L two-dimensional MPSK signal sets. A systematic approach to partitioning L×MPSK signal sets that is based on block coding is used. An encoder system approach is developed. It incorporates the design of a differential precoder, a systematic convolutional encoder, and a signal set mapper. Trellis-coded L×4PSK, L×8PSK, and L×16PSK modulation schemes are found for 1⩽L⩽4 and a variety of code rates and decoder complexities, many of which are fully transparent to discrete phase rotations of the signal set. The new codes achieve asymptotic coding …


Benchmarking Parallel Machines Via A Software Architecture, Srikanth Kambhatla, Jon Inouye, Jonathan Walpole Jan 1990

Benchmarking Parallel Machines Via A Software Architecture, Srikanth Kambhatla, Jon Inouye, Jonathan Walpole

Computer Science Faculty Publications and Presentations

The diversity in parallel architectures and the programming styles induced thereof, make benchmarking of parallel machines a hard problem. Current benchmarking techniques are limited in applicability due to the issues of portability. We present a different approach to benchmarking parallel machines, which would make the resulting benchmarks portable, easy to use and widely applicable. The approach involves the use of a software architecture to mask the diversities of the underlying architectures. The benchmarks are based on the Linda Tuple Space, and is called BeLinda. In this report, we motivate the use of a software architecture, give a specification of the …


The Development Of An Expert System For The Diagnosis Of Diseases In Fibre And Dairy Goats, Tim S. Roberts Jan 1990

The Development Of An Expert System For The Diagnosis Of Diseases In Fibre And Dairy Goats, Tim S. Roberts

Theses: Doctorates and Masters

This thesis details the development of an expert system for the diagnosis of diseases in fibre and dairy goats. Divided into five sections, five appendices, and a bibliography, this thesis centres on the methods used to build the expert system: the decisions taken at the outset of, and during the course of, development; some of the problems encountered, and the solutions to those problems. A detailed appraisal is made of the development process and suggestions are made for future developments over similar domains (for example, the diagnosis of diseases in animals other than goats). Much emphasis is placed on three …


Development Of An Expert System To Convert Knowledge-Based Geological Engineering Systems Into Fortran, Jill J. Cress, Ralph W. Wilkerson Dec 1989

Development Of An Expert System To Convert Knowledge-Based Geological Engineering Systems Into Fortran, Jill J. Cress, Ralph W. Wilkerson

Computer Science Technical Reports

A knowledge-based geographic information system (KBGIS) for geological engineering map (GEM) production was developed in GoldWorks, an expert system development shell. GoldWorks allows the geological engineer to develop a rule base for a GEM application. Implementation of the resultant rule base produced a valid GEM, but took too much time. This proved that knowledge-based GEM production was possible but in GoldWorks implementation failed as a practical production system. To solve this problem, a Conversion Expert System was developed which accepted, as input, a KBGIS and produced, as output, the equivalent Fortran code. This allowed the engineer to utilize GoldWorks for …


The Directed Steiner Problem On Graphs: A Simulated Annealing Approach, Lawrence Joseph Osborne, Billy E. Gillett Dec 1989

The Directed Steiner Problem On Graphs: A Simulated Annealing Approach, Lawrence Joseph Osborne, Billy E. Gillett

Computer Science Technical Reports

The well-known Steiner Problem on Graphs is an NP-complete problem for which there are many heuristic and exact algorithms that are deterministic. In this dissertation a new approach to the directed version of this problem is made by applying the ideas of statistical mechanics through the use of the method of simulated annealing. A version of annealing is developed for the Directed Steiner Problem and compared with one of the best general annealing schemes. Then a comparison is made between simulated annealing and the traditional branch and bound technique. The dual ascent algorithm of Richard T. Wong is used to …