Digital Commons Network^™

An Application-Oriented Error Control Scheme For High Speed Networks, Fengmin Gong, Gurudatta Parulkar

All Computer Science and Engineering Research

Many new network applications demand interprocess communication (IPC) services that are not supported by existing transport protocol mechanisms. Large bandwidth-delay products of high-speed networks also render the existing control mechanisms such as flow and error control less efficient. In particular, new error control schemes that can provide variable degrees of error recovery according to the applications requirements are needed. This paper presents the design, evaluation, and implementation of an application-oriented error control scheme that is aimed at supporting efficient IPC in high-speed networking environments. Our results show that the proposed error control scheme allows effective control of trade-off between the …

An Incremental Distributed Algorithm For Computing Biconnected Components, Bala Swaminathan, Kenneth J. Goldman

All Computer Science and Engineering Research

This paper describes a distributed algorithm for computing the biconnected components of a dynamically changing graph. Our algorithm has a worst case communication complexity of O(b + c) messages for an edge insertion and O(b' + c) messages for an edge removal, and a worst case time complexity of O(c) for both operations, where c is the maximum number of biconnected components in any of the connected components during the operation, b is the number of nodes in the biconnected component containing the new edge, and bprime is the number of nodes in the biconnected component in which the update …

Visual Presentation Of Software Specifications And Designs, Gruia-Catalin Roman, Delbert Hart, Charles Calkins

All Computer Science and Engineering Research

Formal methods hold the promise for high dependability in the design of critical software. However, software engineers who employ formal methods need to communicate their design decisions to users, customers, managers, and collegues who may not be in a position to acquire a full understanding of the formal notation being used. Visualizations derived from formal specifications and designs must be able to convey the required information precisely and reliably without the use of formal notation. This paper discusses a design methodology which attempts to integrate a design methodology based upon specification and program refinement with a state-of-the-art approach to rapid …

Distributed Multimedia Systems Research Prospectus, Jonathan Turner

All Computer Science and Engineering Research

Distributed multimedia computing and communiation systems combine computer systems, networks and distributed software to facilitate applications that enable and enhance collaborative work, direct interpersonal communication, remote access to information and real-time presentation of information from a variety of sources. Over the next decade, we expect such systems to become central to the infrastructure of our increasingly information-driven society. This prospectus describes a program of research being pursued within the Computer and Communications Research Center of Washington University and the Departments of Computer Science and Electrical Engineering. This program seeks to promote the creation of effective distributed multimedia systems and develop …

Connection Management In Reconfigurable Distributed Systems, Bala Swaminathan

All Computer Science and Engineering Research

The Programmer's Playground takes a new approach to simplifying and supporting the construction of distributed applications. The approach, called I/O abstraction, separates the description of a system's communication structure from the descriptions of its computational components so that software modules written in existing programming languages cna be integrated flexibly and dynamically by both programmers and end-users. This separation is achieved by estabishing logical connectinos among the data interfaces of independent software modules. The logical connections provide a uniform high-level view of communication for both discrete and continuous data. The I/O abstraction approach inherits ideas from the I/O automaton model, a …

A Semantic Framework For Understanding The Behavior Of Modules And Classes In Programming Languages, Mahesh Dodani, Benjamin Kok Siew Gan

Research Collection School Of Computing and Information Systems

Recent trends in programming language design and implementation are aimed at integrating the two most important constructs to combat complexity: modules and classes. Both constructs provide encapsulation, a cornerstone of reliable programming. These constructs differ in their approach to building hierarchies: modules define visibility of components while classes define visibility of functionality. How can modules and classes be effectively integrated within a simple programming language? This question captures the essence of developing semantics of these constructs to ensure that they interact in a meaningful way. This paper develops a formal denotational semantic framework for understanding the interaction between classes and …

On The Equivalence Of Mceliece's And Niederreiter's Public-Key Cryptosystems, Y. X. Li, Robert H. Deng, X. M. Wang

Research Collection School Of Computing and Information Systems

It is shown that McEliece's and Niederreiter's public-key cryptosystems are equivalent when set up for corresponding choices of parameters. A security analysis for the two systems based on this equivalence observation, is presented

An Improved Characterization Of 1-Step Recoverable Embeddings: Rings In Hypercubes, Jun-Lin Liu, T.J. Sager, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

An embedding is 1-step recoverable if any single fault occurs, the embedding can be reconfigured in one reconfiguration step to maintain the structure of the embedded graph. In this paper we present an efficient scheme to construct this type of 1-step recoverable ring embeddings in the hypercube. Our scheme will guarantee finding a 1-step recoverable embedding of a length-k (even) ring in a d-cube where 6 less than or equal to k less than or equal to (3/4)2/sup d/ and d greater than or equal to 3, provided such an embedding exists. Unlike previously proposed schemes, we solve the general …

The Management Of Information Technology Investments In The Australian Ambulance Services, Anthony J. Ahern

Theses: Doctorates and Masters

Information Technology plays a significant role in the administration and operation of most organisations today. This is certainly the case with each of the Australian Ambulance Services. With the rapid increase in the use of Information Technology and the expectation about its use by both staff and the general public, the Ambulance Service managements' are faced with the dilemma of trying to ensure that their organisations are able to get the full advantage of advances in Information Technology and at the same time ensure that investments in IT are maintained at appropriate levels that will ensure the maximum return on …

Software Metrics For Monitoring Software Engineering Projects, Edwin C. Lim

Theses: Doctorates and Masters

As part of the undergraduate course offered by Edith Cowan University, the Department of Computer Science has (as part of a year's study) a software engineering group project. The structure of this project was divided into two units, Software Engineering l and Software Engineering 2. ln Software Engineering 1, students were given the group project where they had to complete and submit the Functional Requirement and Detail System Design documentation. In Software Engineering 2, students commenced with the implementation of the software, testing and documentation. The software was then submitted for assessment and presented to the client. To aid the …

Visualisation Of Inshore Marine Water Depth Data, Karen Powell

Theses : Honours

The literature review performed as part of this Project concentrated on two objectives. The first objective was the identification of techniques applicable to the visualisation of the inshore marine water depth data obtained from the Department of Marine & Harbours (M&H). The second objective involved examining how colour is best used within data visualisation. The experimentation investigated a simple method for interpreting movement between depth surveys undertaken by M&H. Although it achieved the objective of creating a longer and smoother animation, it was concluded that the movement of the harbour floor was not accurately represented. The Project applied an optical …

Measurement Of The Cross Section For Γγ→Pp̄, Artuso, M.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.

Identifying Faces Using Multiple Retrievals, Jian Kang Wu, Arcot Desai Narasimhalu

Research Collection School Of Computing and Information Systems

During a police investigation, officers often have to sort through hundreds of photographs to identify a suspect. To aid this task, we at the Institute of Systems Science developed and implemented a flexible database system that can retrieve faces using personal information, fuzzy and free-text descriptors, and classification trees.

The World Wide Web And Technology Transfer At Nasa Langley Research Center, Michael L. Nelson, David J. Bianco

Computer Science Faculty Publications

NASA Langley Research Center (LaRC) began using the World Wide Web (WWW) in the summer of 1993, becoming the first NASA installation to provide a Center-wide home page. This coincided with a reorganization of LaRC to provide a more concentrated focus on technology transfer to both aerospace and non-aerospace industry. Use of the WWW and NCSA Mosaic not only provides automated information dissemination, but also allows for the implementation, evolution and integration of many technology transfer applications. This paper describes several of these innovative applications, including the on-line presentation of the entire Technology Opportunities Showcase (TOPS), an industrial partnering showcase …

Electronic Document Distribution: Design Of The Anonymous Ftp Langley Technical Report Server, Michael L. Nelson, Gretchen L. Gottlich

Computer Science Faculty Publications

An experimental electronic dissemination project, the Langley Technical Report Server (LTRS), has been undertaken to determine the feasibility of delivering Langley technical reports directly to the desktops of researchers worldwide. During the first six months, over 4700 accesses occurred and over 2400 technical reports were distributed. This usage indicates the high level of interest that researchers have in performing literature searches and retrieving technical reports at their desktops. The initial system was developed with existing resources and technology. The reports are stored as files on an inexpensive UNIX workstation and are accessible over the Internet. This project will serve as …

World Wide Web Implementation Of The Langley Technical Report Server, Michael L. Nelson, Gretchen L. Gottlich, David J. Bianco

Computer Science Faculty Publications

On January 14, 1993, NASA Langley Research Center (LaRC) made approximately 130 formal, 'unclassified, unlimited' technical reports available via the anonymous FTP Langley Technical Report Server (LTRS). LaRC was the first organization to provide a significant number of aerospace technical reports for open electronic dissemination. LTRS has been successful in its first 18 months of operation, with over 11,000 reports distributed and has helped lay the foundation for electronic document distribution for NASA. The availability of World Wide Web (WWW) technology has revolutionized the Internet-based information community. This paper describes the transition of LTRS from a centralized FTP site to …

A Strategy For Electronic Dissemination Of Nasa Langley Technical Publications, Donna G. Roper, Mary K. Mccaskill, Scott D. Holland, Joanne L. Walsh, Michael L. Nelson, Susan L. Adkins, Manjula Y. Ambur, Bryan A. Campbell

Computer Science Faculty Publications

To demonstrate NASA Langley Research Center's relevance and to transfer technology to external customers in a timely and efficient manner, Langley has formed a working group to study and recommend a course of action for the electronic dissemination of technical reports (EDTR). The working group identified electronic report requirements (e.g., accessibility, file format, search requirements) of customers in U.S. industry through numerous site visits and personal contacts. Internal surveys were also used to determine commonalities in document preparation methods. From these surveys, a set of requirements for an electronic dissemination system was developed. Two candidate systems were identified and evaluated …

Issues And Obstacles With Multimedia Authoring, Fillia Makedon, Samuel A. Rebelsky, Matthew Cheyney, Charles Owen, Peter Gloor

Dartmouth Scholarship

Unlike traditional authoring, multimedia authoring involves making hard choices, forecasting technological evolution and adapting to software and hardware technology changes. It is, perhaps, an unstable field of endeavor for an academic to be in. Yet, it is important that academics are, in fact, part of this process. This paper discusses some of the common threads shared by three dissimilar cases of multimedia authoring which we have experimented with, that of multimedia conference proceedings, multimedia courseware development and multimedia information kiosks. We consider these applications from an academic point of view and review the benefits and pitfalls of academic development while …

A Study Of The Approaches And Attitudes Of Information Systems Executives To Measuring Information Systems Effectiveness, Falantina Tjakra

Theses: Doctorates and Masters

The purpose of the research is to examine the attitudes of IS executives to the current and future importance of some of the approaches to measuring IS efficiency and IS effectiveness in large Australian organisations. The study identified the nature of IS effectiveness approaches along the lines of whether they are business-oriented, IS internal/operational, financial, quantitative or qualitative measures. It also examined whether the structure of the IS management and industry sector had an effect on attitudes towards these measures.

Applications Of Fuzzy Counterpropagation Neural Networks To Non-Linear Function Approximation And Background Noise Elimination, I. M. Wiryana

Theses: Doctorates and Masters

An adaptive filter which can operate in an unknown environment by performing a learning mechanism that is suitable for the speech enhancement process. This research develops a novel ANN model which incorporates the fuzzy set approach and which can perform a non-linear function approximation. The model is used as the basic structure of an adaptive filter. The learning capability of ANN is expected to be able to reduce the development time and cost of the designing adaptive filters based on fuzzy set approach. A combination of both techniques may result in a learnable system that can tackle the vagueness problem …

A Model Of Visual Recognition Implemented Using Neural Networks, Vincent C. Phillips

Theses: Doctorates and Masters

The ability to recognise and classify objects in the environment is an important property of biological vision. It is highly desirable that artificial vision systems also have this ability. This thesis documents research into the use of artificial neural networks to implement a prototype model of visual object recognition. The prototype model, describing a computtional architecture, is derived from relevant physiological and psychological data, and attempts to resolve the use of structural decomposition and invariant feature detection. To validate the research a partial implementation of the model has been constructed using multiple neural networks. A linear feed-forward network performs pre-procesing …

A Simulated Annealing/Tabu Search Algorithm For The Vehicle Routing Problem, Jeffrey Dale White, Billy E. Gillett

Computer Science Technical Reports

The Vehicle Routing Problem is an NP-complete problem that has been studied extensively since it was introduced in 1958 by G. B. Dantzig and J. H. Ramser. This thesis creates three algorithms that endeavor to find an optimal solution for each problem tested. Two of the algorithms (Simulated Annealing and Tabu Search) have been used previously to solve this problem. These two solution methods are revisited to discover whether a new approach to creating routes will produce the best-known optimal values every time. New routes are created by forming route neighborhoods and then selecting cities from these neighborhoods for insertion. …

Process Driven Software Engineering Environments, John Hayes Lampkin, T. Lo, Daniel C. St. Clair

Computer Science Technical Reports

Software development organizations have begun using Software Engineering Environments (SEEs) with the goal of enhancing the productivity of software developers and improving the quality of software products. The encompassing nature of a SEE means that it is typically very tightly coupled with the way an organization does business. To be most effective, the components of a SEE must be well integrated and the SEE itself must be integrated with the organization.

The challenge of tool integration increases considerably when the components of the environment come from different vendors and support varying degrees of “openness”. The challenge of integration with the …

Subsumption In Modal Logic, Dirk Heydtmann, Ralph W. Wilkerson

Computer Science Technical Reports

Subsumption has long been known as a technique to detect redundant clauses in the search space of automated deduction systems for classical first order logic. In recent years several automated deduction methods for non-classical modal logics have been developed. This thesis explores, how subsumption can be made to work in the context of these modal logic deduction methods.

Many modern modal logic deduction methods follow an indirect approach. They translate the modal sentences into some other target language, and then determine whether there exists a proof in that language, rather than doing deduction in the modal language itself. Consequently, subsumption …

Fault-Tolerant Ring Embeddings In Hypercubes -- A Reconfigurable Approach, Jun-Lin Liu, Bruce M. Mcmillin

Computer Science Technical Reports

We investigate the problem of designing reconfigurable embedding schemes for a fixed hypercube (without redundant processors and links). The fundamental idea for these schemes is to embed a basic network on the hypercube without fully utilizing the nodes on the hypercube. The remaining nodes can be used as spares to reconfigure the embeddings in case of faults. The result of this research shows that by carefully embedding the application graphs, the topological properties of the embedding can be preserved under fault conditions, and reconfiguration can be carried out efficiently.

In this dissertation, we choose the ring as the basic network …

Design And Development Of A Heterogeneous Parallel Computing System, Eruch R. Rustomji

Masters Theses

A parallel and distributed processing environment can be defined as one where a set of workstations is configured in a certain topology (such as completely connected linear chain) to simulate the working of a particular parallel architecture. Such an environment provides an extremely useful means of experimenting with parallel algorithms, without the use of expensive dedicated parallel machines.

Several parallel and distributed processing environments exist, such as Parallel Virtual Machine, The Condor System and the Reactive Kernel System/ Cosmic Environment System. Each of these systems has some unique features and limitations. Other systems include p4, Hermes, Linda and Express.

This …

Using Database Technology To Support Domain-Oriented Application Composition Systems, Danny A. Cecil, Joseph A. Fullenkamp

Theses and Dissertations

This research designed and prototyped an OODBMS technology base to store and retrieve various types of domain artifacts for domain-oriented application composition systems (DOACS). We developed object-oriented database schemas for a validating domain and the Object-Connection-Update software architecture. We implemented an inheritance relationship between the schemas so a domain model can inherit an architectural structure from an architecture model allowing us to isolate domain-specific knowledge from architecture-specific knowledge. We also developed a meta-model to formally define domain models in the database. We then developed a set of database methods to transform a domain model into a database schema for storing …

A Prototype Architecture For An Automated Scenario Generation System For Combat Simulations, Mark W. Pfefferman

Theses and Dissertations

This research effort examines the problem of automating the scenario generation process and presents a prototype architecture for an automated scenario generation system. This architecture is designed using an object- oriented approach which leads to a modular and modifiable design. The architecture provides a mechanism for automatically generating scenario files from a textual US Army operation order. This translation process occurs in two phases. First, the text operation order is translated into an intermediate format called the mission file. In the second phase, the system reads the mission file, instantiates intelligent entities, and assigns missions to those entities. The intelligent …

Design Of A Shared Coherent Cache For A Multiple Channel Architecture, John A. Reisner

Theses and Dissertations

The Multiple Channel Architecture MCA is a recently proposed computer architecture which uses fiber optic communications to overcome many of the problems associated with interconnection networks. There exists a detailed MCA simulator which faithfully simulates an MCA system, however, the original version of the simulator did not cache shared data. In order to improve the performance of the MCA, a cache coherency protocol was developed and implemented in the simulator. The protocol has two features which are significant: (1) a time-division multiplexed TDM communication bus is used for coherency traffic, and (2) the shared data is cached in an independent …

Development Of Computer Software To Aid Environmental Decision Makers In The Education And Training Of Air Force Remedial Project Managers, Roger R. Ouellette, Bruce K. Lyman

Theses and Dissertations

By the end of Fiscal Year 1991, the Air Force had identified 4,354 contaminated sites. Much like the 177 toxic sites at McClellan AFB, bases across the country and throughput the world are filled with chrome, lead, paint solvents and many other toxics that are rendering water supplies unusable and endangering the health of millions of people living in and around these bases. Air Force officials continue to identify contaminated sites with no end in sight. Since the cleanup of these toxic materials involves diverse, complex activities, the Air Force created the duty position of Remedial Project Manager to manage …