Digital Commons Network^™

Vaudeville: A High Performance, Voice-Activated Teleconferencing Application, Jyoti K. Parwatikar, T. Paul Mccartney, John D. Dehart, Maynard Engebretson, Kenneth J. Goldman

All Computer Science and Engineering Research

We present a voice-activated, hands-off, ATM-based video conferencing application. The application, called Vaudeville, features high quality NTSC video, voice-activated audio transmission, audio bridging of two audio streams, and voice-activated video switching. It supports multiple simultaneous multi-party conferences using a scalable multicast mechanism. We describe how Vaudeville was built using a component-based distributed programming environment. We also describe the algorithms used to contorl the audio and video of the applciation. Audio and video are encoded in hardware using an ATM hardware multimedia interface.

End-User Construction And Configuration Of Distributed Multimedia Applications, Terrance Paul Mccartney

All Computer Science and Engineering Research

Distributed multimedia applications supported by a global electronic infrastructure have tremendous potential for providing users with customized communication and computation environments. Since communication and computation requirements vary by context and change dynamically, it is unlikely that off-the-shelf applications will anticipate the needs of all users. Therefore, empowering end-users to create their own customized applications for both communication and computation is an important challenge. This dissertation presents several mechanisms that enable end-users to create and configure distributed multimedia applications, including end-users construction direct manipulation graphical users interface (GUIs) and application management of distributed multimedia applications over the Internet.

Distributed Stream Filtering For Database Applications, William M. Shapiro, Kenneth J. Goldman

All Computer Science and Engineering Research

Distributed stream filtering is a mechanism for implementing a new class of real-time applications with distributed processing requirements. These applications require scalable architectures to support the efficient processing and multiplexing of large volumes of continuously generated data. This paper provides an overview of a stream-oriented model for database query processing and presents a supporting implementation. To facilitate distributed stream filtering, we introduce several new query processing operations, including pipelined filtering that efficiently joins and eliminates duplicates from database streams and a new join method, the progressive join, that joins streams of tuples. Finally, recognizing that the stream-oriented model results in …

Building Distributed Applications With Design Patterns, Gruia-Catalin Roman, James C. Hu

All Computer Science and Engineering Research

Design patterns are a topic of great current interest within the object-oriented programming community. The motivation is both economical and intellectual. On one hand, there is the hope of establishing a common culture and language that fosters communicatino and growth in the software engineering field. While a community dominated by empiricism is seeking to achieve higher levels of formality by capturing its experiences in the form of catalogs of design patterns, another community, deeply rooted in formal thinking, is seeking to make its mark on the every day workings of the software engineering process. Distributed algorithms and the heuristics used …

Software Quality: Definitions And Strategic Issues, Ronan Fitzpatrick

Reports

This paper contains two sections relating to software quality issues. First, the various definitions of software quality are examined and an alternative suggested. It continues with a review of the quality model as defined by McCall, Richards and Walters in 1977 and mentions the later model of Boëhm published in 1978. Each of McCall's quality factors is reviewed and the extent to which they still apply in the late 1990s is commented on. The factors include, integrity, reliability, usability, accuracy, efficiency, maintainability, testability, flexibility,interface facility (interoperability), re-usability and transferability (portability). They are subdivided into external and internal quality factors. Interrelationships …

A Framework For Integrated Communication And I/O Placement, Rajesh Bordawekar, Alok Choudhary, J Ramanujam

Electrical Engineering and Computer Science - All Scholarship

This paper describes a framework for analyzing dataflow within an out-of-core parallel program. Dataflow properties of FORALL statement are analyzed and a unified I/O and communication placement framework is presented. This placement framework can be applied to many problems, which include eliminating redundant I/O incurred in communication. The framework is validated by applying it for optimizing I/O and communication in out-of-core stencil problems. Experimental performance results on an Intel Paragon show significant reduction in I/O and communication overhead.

Terminal Sliding Mode Control For Rigid Robotic Manipulators With Uncertain Dynamics, Nicola Ritter

Theses: Doctorates and Masters

This thesis presents two new adaptive control laws that use the terminal sliding mode technique for the tracking problem of rigid robotic manipulators with non-linearities, dynamic couplings and uncertain parameters. The first law provides a robust scheme which uses several properties of rigid robotic mauipulators and adaptively adjusts seven uncertain parameter bounds. The law ensures finite time error convergence to the system origin and is simple to implement The second law treats the manipulator as a partially known system. The known dynamics are used to build a nominal control law and the effects of unknown system dynamics arc compensated for …

The Mobile Telephone: The Transportation Of Social Relationships, Kenneth C. Staples

Theses: Doctorates and Masters

In the studies of contemporary electronic media artifacts and their effects on society, television, satellites, and computers have been extensively investigated and their various impacts well documented. With regards to telecommunication technologies, academic scholarship is somewhat less, with most comment being restricted to either historic evolution, or technical description. Exceptions to this are, Marvin's reference to the telephone in her publication, When Old Technologies Were New: Thinking About Electronic Communication in the Late Nineteenth Century (1988}, and Umble's The Amish and the telephone: resistance and reconstruction (1992). Both of these publications are used for supporting arguments in my thesis investigating …

Semantic Correlation Of Behavior For The Interoperability Of Heterogeneous Simulations, Christopher James Dean

Retrospective Theses and Dissertations

A desirable goal of military simulation training is to provide large scale or joint exercises to train personnel at higher echelons. To help meet this goal, many of the lower echelon combatants must consist of computer generated forces with some of these echelons composed of units from different simulations. The object of the research described is to correlate the behaviors of entities in different simulations so that they can interoperate with one another to support simulation training. Specific source behaviors can be translated to a form in terms of general behaviors which can then be correlated to any desired specific …

Analysis Of Background Noise For Wireless Microwave Lan Channels, Jason C. Hislop

Theses : Honours

Perusal of the details within, should provide the reader with an insight into general wireless indoor communications within the microwave spectrum, with respect to the problems laced, specific to noise corruption of the transmitted signal. Indoor communication systems are difficult to model, due to the largely random nature of the relevant environment, and the compounding factors that degrade system performance. These factors are many and varied, in accordance with the operational topologies of possible application area. However, there exists a common and increasing need to effectively model the communication links in question. Part of this strategy involves having an understanding …

Simulator For The Performance Analysis Of Cpm Schemes In An Indoor Wireless Environment, Ronald Chua

Theses : Honours

A software simulator for characterising Continuous Phase Modulation (CPM) schemes in an indoor multipath environment has been developed using SIMULINK and MATLAB. The simulator is capable of simulating a wide range of CPM schemes to determine bandwidth efficiency and robustness to additive white Gaussian noise (AWGN) and Rician fading. Initial trials of the simulator indicate that the simulator is functioning correctly. Eventually, the simulator will be used to determine the most suitable modulation scheme for the development of an actual indoor wireless system.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 11, Number 10, December 1995, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A twelve page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Adaptive Methods For Distributed Video Presentation, Crispin Cowan, Shanwei Cen, Jonathan Walpole, Carlton Pu

Computer Science Faculty Publications and Presentations

This paper describes problems and solutions for delivering real-time, multi-media presentations across the Internet. A key characteristic of presentations of continuous media datatypes, such as digital video and audio, is their need for predictable real-time data delivery. For example, an NTSC quality video presentation requires video frames to be displayed every 1/30th of a second. Variations in this display rate can be observable as stalls or glitches in the video stream and reduce the quality of the presentation [6]. Delivering such presentations across the Internet is difficult because highly variable band- width and latency make it difficult to predict the …

The Automated Wingman: An Airborne Companion For Users Of Dis Compatible Flight Simulators, Mark M. Edwards

Theses and Dissertations

A major problem encountered by users of distributed virtual environments is the lack of simulators available to populate these environments. This problem is usually remedied by using computer generated entities. Unfortunately, these entities often lack adequate human behavior and are readily identified as non-human. This violates the realism premise of distributed virtual reality and is a major problem, especially in training situations. This thesis addresses the problem by presenting a computer generated entity called the Automated Wingman. The Automated Wingman is a semi-automated computer generated aircraft simulator that operates under the control of a designated lead simulator and integrates distributed …

An Architecture For Dynamic Meta-Level Process Control For Model-Based Troubleshooting, John E. Friskie

Theses and Dissertations

There are numerous methods used for troubleshooting devices. Each method has certain domains, knowledge requirements, and assumptions required for it to perform well. However, oftentimes no one method by itself is sufficient to completely solve a troubleshooting problem. Therefore, an architecture is required to control the combined use of many problem solving methods. The combination of multiple problem solving methods makes the troubleshooting process more robust in terms of device domains that can be dealt with and quality of diagnoses produced. Troubleshooting has two tasks: diagnosis and problem resolution. This research provides an architecture that allows dynamic method selection during …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 11, Number 9, November 1995, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A twelve page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Aliasing Reduction In Staring Infrared Imagers Utilizing Subpixel Techniques, Joseph C. Gillette, Thomas M. Stadtmiller, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

We introduce and analyze techniques for the reduction of aliased signal energy in a staring infrared imaging system. A standard staring system uses a fixed two-dimensional detector array that corresponds to a fixed spatial sampling frequency determined by the detector pitch or spacing. Aliasing will occur when sampling a scene containing spatial frequencies exceeding half the sampling frequency. This aliasing can significantly degrade the image quality. The aliasing reduction schemes presented here, referred to as microscanning, exploit subpixel shifts between time frames of an image sequence. These multiple images are used to reconstruct a single frame with reduced aliasing. If …

Device And Physical Data Independence For Multimedia Presentations, Richard Staehli, Jonathan Walpole, David Maier

Computer Science Faculty Publications and Presentations

Multimedia computing promises access to any type of visual or aural medium on the desktop. But in this networked future, will every type of media be accessible from every terminal device? Current multimedia standards do not allow content that is authored for high-bandwidth workstations to scale down for low-bandwidth applications. The problem is that application requests are commonly interpreted as requests for the highest possible quality and resource overloads are handled by ad hoc methods. We can begin to solve this problem by specifying Quality of Service (QOS) requirements based on functionality rather than on content encoding and device capabilities.

Customizable Operating Systems, Jonathan Walpole, Crispin Cowan, Andrew P. Black, Jon Inouye, Calton Pu, Shanwei Cen

Computer Science Faculty Publications and Presentations

A customizable operating system is one that can adapt to improve its functionality or performance. The need for customizable and application-specific operating systems has been recognized for many years, but they have yet to appear in the commercial market. This paper explores the notion of operating system customizability and examines the limits of existing approaches. The paper begins by surveying system structuring approaches for the safe and efficient execution of customizable operating systems. Then it discusses the burden that existing approaches impose on application software, and explores techniques for reducing this burden. Finally, support for customizability in the Synthetix project …

Quality Of Service Specification For Multimedia Presentations, Richard Staehli, Jonathan Walpole, David Maier

Computer Science Faculty Publications and Presentations

The bandwidth limitations of multimedia systems force tradeoffs between presentation data fidelity and real-time performance. For example, digital video is commonly encoded with lossy compression to reduce bandwidth and frames may be skipped during playback to maintain synchronization. These tradeoffs depend on device performance and physical data representations that are hidden by a database system. If a multimedia database is to support digital video and other continuous media data types, we argue that the database should provide a Quality of Service (QOS) interface to allow application control of presentation timing and information loss tradeoffs.

This paper proposes a data model …

Device And Physical Data Independence For Multimedia Presentations, Richard Staehli, Jonathan Walpole, David Maier

Computer Science Faculty Publications and Presentations

Multimedia computing promises access to any type of visual or aural medium on the desktop. But in this networked future, will every type of media be accessible from every terminal device? Current multimedia standards do not allow content that is authored for high-bandwidth workstations to scale down for low-bandwidth applications. The problem is that application requests are commonly interpreted as requests for the highest possible quality and resource overloads are handled by ad hoc methods. We can begin to solve this problem by specifying Quality of Service (QOS) requirements based on functionality rather than on content encoding and device capabilities.

A Computer-Aided Software Engineering (Case) Approach To Business Process Reengineering (Bpr), Faiza I. Khan

Master's Theses - Daytona Beach

This thesis addresses the problem of lack of procedures by which managers can identify business processes that would benefit from reengineering and which could be used to guide the BPR activity to its successful conclusion. The purpose of this study is to analyze various Software Engineering (SE) principles to determine whether they could be used to support Business Process Reengineering (BPR) activities either directly or with some modification, and if so, whether available Computer-Aided Software Engineering (CASE) tools might be applied to BPR in support of managers who wish to implement it. The principles of SE and BPR are discussed …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 11, Number 8, October 1995, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Atomic Broadcast In Heterogeneous Distributed Systems, Osman Zeineldine

Computer Science Theses & Dissertations

Communication services have long been recognized as possessing a dominant effect on both performance and robustness of distributed systems. Distributed applications rely on a multitude of protocols for the support of these services. Of crucial importance are multicast protocols. Reliable multicast protocols enhance the efficiency and robustness of distributed systems. Numerous reliable multicast protocols have been proposed, each differing in the set of assumptions adopted, especially for the communication network. These assumptions make each protocol suitable for a specific environment. The presence of different distributed applications that run on different LANs and single distributed applications that span different LANs mandate …

Safe Stratified Datalog With Integer Order Programs, Peter Revesz

School of Computing: Conference and Workshop Papers

Guaranteeing termination of programs on all valid inputs is important for database applications. Termination cannot be guaranteed in Stratified Datalog with integer (gap)-order programs on generalized databases because they express any Turing-computable function. This paper introduces a restriction of those programs that can express only computable queries. The restricted language has a high expressive power and a non-elementary data complexity.

Teaching Upper Level Computer Science Courses Via Virtual Classroom And Video : Course Reports By Faculty, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Julian M. Scher, Michael Bieber, Murray Turoff

Computerized Conferencing and Communications Center Reports

New Jersey Institute of Technology is the grateful recipient of a generous grant from the Alfred P. Sloan Foundation which has enabled it to explore the use of asynchronous learning networks to create and deliver an entire undergraduate degree program in computer and information science. Each of these courses uses some amount of lecture-type material delivered via videotape. These materials are usually available to students in three different ways: by viewing broadcasts on a New Jersey cable station, by renting the set of videotapes, or by viewing in a special room in the library. Videotapes for distance learning are not …

Teaching Lower Level Computer Science Courses Via Virtual Classroom And Video : Course Reports By Faculty, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Fadi Deek, Maura Deek, James Geller, Ajaz R. Rana

Computerized Conferencing and Communications Center Reports

New Jersey Institute of Technology is the grateful recipient of a generous grant from the Alfred P. Sloan Foundation which has enabled it to explore the use of asynchronous learning networks to create and deliver an entire undergraduate degree program in computer and information science. Each of these courses uses some amount of lecture-type material delivered via videotape. These materials are usually available to students in three different ways: by viewing broadcasts on a New Jersey cable station, by renting the set of videotapes, or by viewing in a special room in the library. Videotapes for distance learning are not …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 11, Number 7, September 1995, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A six page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Linda Jacobson Interview Virtual Reality Evangelist, Loretta L. Lange

SWITCH

In the interview with Linda Jacobson, a Virtual Reality (VR) artist, Jacobson discusses the current and future state of VR technology’s role in the politics of the body, social identity, self, gender, class, and race. This article discusses the fact that barriers to access exist for a more diverse set of artists across race, class, and gender to engage with VR technology and the need to evolve the development platform, so artists can implement their ideas in a low-cost way. The author discusses Jaron Lanier’s ideas about using VR to explore other identities based on a theatrical model where the …

Broadband Dynamic, Holographically Self-Recorded, And Static Hexagonal Scattering Patterns In Photorefractive Knbo3:Fe, Nickolai Kukhtarev, Tatiana V. Kukhtareva, John Caulfield, Partha P. Banerjee, Hsueh-Ling Yu, Lambertus Hesselink

Electrical and Computer Engineering Faculty Publications

We have observed and explained three types of hexagon pattern formation in photo refractive crystal KNb03:Fe. These are:

• Dynamic (laser induced)
• Semipermanent (holographically stored)
• Permanent (induced by a static domain grid) over a wide wavelength range