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Learning In A Fuzzy Logic Robot Controller, Doug Blank, J. O. Ross Jan 1997

Learning In A Fuzzy Logic Robot Controller, Doug Blank, J. O. Ross

Computer Science Faculty Research and Scholarship

No abstract provided.

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Development And Evaluation Of Interactive Courseware For Visualization Of Graph Data Structure And Algorithms, Thomas E. Beutel Jan 1997

Development And Evaluation Of Interactive Courseware For Visualization Of Graph Data Structure And Algorithms, Thomas E. Beutel

CCAC Theses and Dissertations

The primary goal of this dissertation was to develop and pilot test interactive, multimedia courseware which would facilitate learning the abstract structures, operations, and concepts associated with graph and network data structures in Computer Science. Learning objectives and prerequisites are presented in an introduction section of the courseware and a variety of learning activities are provided including tutorials, animated demonstrations, interactive laboratory sessions, and self-tests. Courseware development incorporated principles and practices from software engineering, instructional design, and cognitive learning theories. Implementation utilized an easy-to-use authoring tool, NeoBook Professional (1994), to create the overall framework and the user interfaces, and Microsoft …

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A Proposed Solution For Word-Recognition Deficit In The Computer Environment, Hyacinth Williams Jan 1997

A Proposed Solution For Word-Recognition Deficit In The Computer Environment, Hyacinth Williams

CCAC Theses and Dissertations

Most college students with reading disabilities have difficulty with word recognition. The purpose of this study was to use an investigator-made cue word list to increase low word recognition skills among college students while creating slides for a university curriculum using a simple presentation tool. The investigator randomly divided fourteen subjects into two groups. One group received the treatment and the other did not. Subjects received fifty minutes to complete a five-slide presentation. The investigator used four different data collection processes for data collection. Beyond this, the investigator presented the results using rank correlation. Results from this study indicated that …

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Lyceum: A Multi-Protocol Digital Library Gateway, Ming-Hokng Maa, Michael L. Nelson, Sandra L. Esler Jan 1997

Lyceum: A Multi-Protocol Digital Library Gateway, Ming-Hokng Maa, Michael L. Nelson, Sandra L. Esler

Computer Science Faculty Publications

Lyceum is a prototype scalable query gateway that provides a logically central interface to multi-protocol and physically distributed, digital libraries of scientific and technical information. Lyceum processes queries to multiple syntactically distinct search engines used by various distributed information servers from a single logically central interface without modification of the remote search engines. A working prototype (http://www.larc.nasa.gov/lyceum/) demonstrates the capabilities, potentials, and advantages of this type of meta-search engine by providing access to over 50 servers covering over 20 disciplines.

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Mobile Unity: A Language And Logic For Concurrent Mobile Systems, Peter J. Mccann, Gruia-Catalin Roman Jan 1997

Mobile Unity: A Language And Logic For Concurrent Mobile Systems, Peter J. Mccann, Gruia-Catalin Roman

All Computer Science and Engineering Research

Traditionally, a distributed system has been viewed as a collection of fixed computational elements connected by a static network. Prompted by recent advances in wireless communications rechnology, the emerging field of mobile computing is challenging these assumptions by providing mobile hosts with connectivity that may change over time, raising the possibility that hosts may be called upon to operate while only weakly connected to or while completely disconnected from other hosts. We define a concurrent mobile system as one where independently executing coponents may migrate through some space during the course of the computation, and where the pattern of connectivity …

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Expressing Code Mobility In Mobile Unity, Gian Pietro Picco, Gruia-Catalin Roman, Peter J. Mccann Jan 1997

Expressing Code Mobility In Mobile Unity, Gian Pietro Picco, Gruia-Catalin Roman, Peter J. Mccann

All Computer Science and Engineering Research

Advancements in network technology have led to the emergence of new computing paradigms that challenge established programming practices by employing weak forms of consistency and dynamic forms of binding. Code mobility, for instance, allows for invocation-time binding between a code fragment and the location where it executes. Similarly, mobile computing allows hosts (and the software they execute) to alter their physical location. Despite apparent similarities, the two paradigms are distinct in their treatment of location and movement. This paper seeks to uncover a common foundation for the two paradigms by exploring the manner in which stereotypical forms of code mobility …

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Alchourron's Defeasible Conditionals And Defeasible Reasoning, Fernando Tohme, Ronald P. Loui Jan 1997

Alchourron's Defeasible Conditionals And Defeasible Reasoning, Fernando Tohme, Ronald P. Loui

All Computer Science and Engineering Research

No abstract provided.

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Principles For Developing And Measuring High-Performance Web Servers Over Atm, James C. Hu, Sumedh Mungee, Douglas C. Schmidt Jan 1997

Principles For Developing And Measuring High-Performance Web Servers Over Atm, James C. Hu, Sumedh Mungee, Douglas C. Schmidt

All Computer Science and Engineering Research

High-performance Web servers are essential to meet the growing demands of the Internet. Satisfying these demands requires a thorough understanding of the key factors that affect Web server performance. This paper provides three contributions to the design, implementation, and evaluation of high-performance Web servers. First, we report the results of a comprehensive empirical study of popular high-performance Web servers (such as Apache, Netscape Enterprise, PHTTPD, and Zeus) over high-speed ATM networks. This study illustrates their relative performance and identifies their performance bottlenecks. To measure performance accurately, we developed a new benchmarking technique that subjects Web servers to varying connection frequencies. …

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Dialogue And Deliberation, Ronald P. Loui, Diana M. Moore Jan 1997

Dialogue And Deliberation, Ronald P. Loui, Diana M. Moore

All Computer Science and Engineering Research

Formal accounts of negotiation tend to invoke the strategic models of conflict which have been impressively developed by game theorists in this half-century. For two decades, however, research on artificial intelligence (AI) has produced a different formal picture of the agent and of the rational deliberations of agents. AI's models are not based simply on intensities of preference and quantities of probability. AI's models consider that agents use language in various ways, that agents use and convey knowledge, that agents plan, search, focus, and argue. Agents can choose their language, apply their knowledge, change their plans, continue their search, shift …

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Building Interactive Distributed Applications In C++ With The Programmers' Playground, Kenneth J. Goldman, Joe Hoffert, T. Paul Mccartney, Jerome Plun, Todd Rogers Jan 1997

Building Interactive Distributed Applications In C++ With The Programmers' Playground, Kenneth J. Goldman, Joe Hoffert, T. Paul Mccartney, Jerome Plun, Todd Rogers

All Computer Science and Engineering Research

The objective of The Programmers' Playground, described in this manual, is to provide a development environment and underlying support for end-user construction of distributed multimedia applications from reusable self-describing software components. Playground provides a set of software tools and a methodology for simplifying the design and construction of applications that interact with each other and with people in a distributed computer system. This manual explains how to write interactive distributed applications using Playground. The only background necessary to get started is an understanding of basic data structures and control constructs in C++. If you already know C++, then with the …

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Learning With Unreliable Boundary Queries, Avrim Blum, Prasad Chalasani, Sally A. Goldman, Donna K. Slonim Jan 1997

Learning With Unreliable Boundary Queries, Avrim Blum, Prasad Chalasani, Sally A. Goldman, Donna K. Slonim

All Computer Science and Engineering Research

We introduce a model for learning from examples and membership queries in situations where the boundary between positive and negative examples is somewhat ill-defined. In our model, queries near the boundary of a target concept may receive incorrect or "don't care" responses, and the distribution of examples has zero probability mass on the boundary region. The motivation behind our model is that in many cases the boundary between positive and negative examples is complicated or "fuzzy." However, one may still hope to learn successfully, because the typical examples that one sees to not come from that region. We present several …

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A Theoretical And Empirical Study Of A Noise-Tolerant Algorithm To Learn Geometric Patterns, Sally A. Goldman, Stephen D. Scott Jan 1997

A Theoretical And Empirical Study Of A Noise-Tolerant Algorithm To Learn Geometric Patterns, Sally A. Goldman, Stephen D. Scott

All Computer Science and Engineering Research

Developing the ability to recognize a landmark from a visual image of a robot's current location is a fundamental problem in robotics. We describe a way in which the landmark matching problem can be mapped to that of learning a one-dimensional geometric pattern. The first contribution of our work is an efficient noise-tolerant algorithm (designed using the statistical query model) to PAC-learn the class of one-dimensional geometric patterns. The second contribution of our work is an empirical study of our algorithm that provides at least some evidence that statistical query algorithms may be valuable for use in practice for handling …

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Architectural Choices In Large Scale Atm Switches, Jonathan Turner, Naoaki Yamanaka Jan 1997

Architectural Choices In Large Scale Atm Switches, Jonathan Turner, Naoaki Yamanaka

All Computer Science and Engineering Research

The rapid development of Asynchronous Transfer Mode technology in the last 10-15 years has stimulated renewed interest in the design and analysis of switching systems, leading to new ideas for system designs and new insights into the performance and evaluation of such systems. As ATM moves closer to realizing the vision of ubiquitous broadband ISDN services, the design of switching systems takes on growing importance. This paper seeks to clarify the key architectural issues for ATM switching system design and provides a survey of the current state-of-the-art.

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Balancing Consistency And Lag In Transaction-Based Computational Steering, Eileen Kraemer, Delbert Hart, Gruia-Catalin Roman Jan 1997

Balancing Consistency And Lag In Transaction-Based Computational Steering, Eileen Kraemer, Delbert Hart, Gruia-Catalin Roman

All Computer Science and Engineering Research

Computational steering, the interactive adjustment of application parameters and allocation of resources, is a promising technique for higher-productivity simulation, finer-grained optimization of dynamically varying algorithms, and greater understanding of program behavior and the characteristics of data sets and solution spaces. Tools for computational steering must provide monitoring, visualization, and interaction facilities. In addition, these tools must address issues related to the consistency, latency, and scalability at each of these phases, and must consider the perturbation that results. In this paper we describe transaction-based components for a computational steering system and present an approach that guarantees consistent monitoring and displays, supports …

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An Architecture For Monitoring Visualization And Control Of Gigabit Networks, Guru Parulkar, Douglas Schmidt, Eileen Kraemer, Jonathan Turner, Anshul Kantawala Jan 1997

An Architecture For Monitoring Visualization And Control Of Gigabit Networks, Guru Parulkar, Douglas Schmidt, Eileen Kraemer, Jonathan Turner, Anshul Kantawala

All Computer Science and Engineering Research

We propose a network monitoring, visualization and control system (NMVC) that ensures adequate quality of service to network users while maintaining high network resource utilization. The main components of our system are a network probe, an endsystem probe, software network management agents that provide extensible multi-attribute event filtering for highly scalable data/event collection, network operation centers (NOCs) which can remotely install and (re)configure these agents, efficient online event ordering algorithms that can help synthesize and display a consistent view of network health, status and performance and a View Choreographer that allows management applications and administrators to specify the mapping of …

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The Programmers' Playground Application Management System User Guide, William M. Shapiro, T. Paul Mccartney, E.F. Berkley Shands Jan 1997

The Programmers' Playground Application Management System User Guide, William M. Shapiro, T. Paul Mccartney, E.F. Berkley Shands

All Computer Science and Engineering Research

Application Management permits the advertising, launching, and configuring of distributed applications created using the Programmers' Playground. Applications can be documented and made available to end-users through the use of application pages on the World Wide Web. The launching and configuring of applications is performed by a brokerage system consisting of an applicatoin broker and one or more hierarchies of module launchers. This document describes how to setup and use the components of the Application Management system.

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Computational Detection Of Cpg Islands In Dna, Eric C. Rouchka, Richard Mazzarella, David J. States Jan 1997

Computational Detection Of Cpg Islands In Dna, Eric C. Rouchka, Richard Mazzarella, David J. States

All Computer Science and Engineering Research

Regions of DNA rich in CpG dinucleotides, also known as CpG islands, are often located upstream of the transcription start side in both tissue specific and housekeeping genes. Overall, CPG dinucleotides are observed at a density of 25% the expected level from base composition alone, partially due to 5-methylcytosine decay (Bird, 1993). Since CpG dinucleotides typically occur with low frequency, CpG islands can be distinguished statistically in the genome. Our method of detecting CpG islands involves a heuristic algorithm employing classic changepoint methods and log-likelihood statistics. A Java applet has been created to allow for user interaction and visualization of …

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Compositional Programming Abstractions For Mobile Computing, Peter J. Mccann, Gruia-Catalin Roman Jan 1997

Compositional Programming Abstractions For Mobile Computing, Peter J. Mccann, Gruia-Catalin Roman

All Computer Science and Engineering Research

Recent advances in wireless networking technology and the increasing demand for ubiquitous, mobile connectivity demonstrate the importance of providing reliable systems for managing reconfiguration and disconnection of components. Design of such systems requires tools and techniques appropriate to the task. Many formal models of computation, including UNITY, are not adequate for expressing reconfiguration and disconnection and are therefore inappropriate vehicles for investigating the impact of mobility on the construction of modular and composable systems. Algebraic formalisms such as the pi-calculus have been proposed for modeling mobility. This paper addresses the question of whether UNITY, a state-based formalism with a foundation …

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Terabit Burst Switching, Jonathan S. Turner Jan 1997

Terabit Burst Switching, Jonathan S. Turner

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This report summarizes the results of an architectural study on Terabit Burst Switching. The purpose of this study was to explore alternative architectures for very high performance switching for data communication, using a combination of optical and electronic technologies. We explore two alternative implementations of the burst switching concept in detail, one using a hybrid architecture with an electronic core, and an integrated architecture using an all optical data path. We also briefly discuss an approach using optical TDM. Our results show that using the hybrid architecture, it is feasible to construct systems with aggregate capacities of tens of terabits …

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End-User Visualization And Manipulation Of Aggregate Data, T. Paul Mccartney, Kenneth J. Goldman Jan 1997

End-User Visualization And Manipulation Of Aggregate Data, T. Paul Mccartney, Kenneth J. Goldman

All Computer Science and Engineering Research

Aggregate visualization and manipulation enables the viewing and interaction of dynamically changing data sets in a graphically meaningful way. However, off-the-shelf applications generally provide only limited ways to view aggregates. To be truly effective to the end-user, an aggregate visualization should be customizable to suit the individual's needs. This paper describes a software system that empowers end-users to create interactive aggregate visualizations through direct manipulation. Included are mechanisms for specifying how aggregate data is processed from multiple sources, providing functionality similar to project, select, join, and cross product of relational databases. Visualization of distributed data sets is emphasized.

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Optimizing The Performance Of The Corba Internet Inter-Orb Protocol Over Atm, Aniruddha Gokhale, Douglas C. Schmidt Jan 1997

Optimizing The Performance Of The Corba Internet Inter-Orb Protocol Over Atm, Aniruddha Gokhale, Douglas C. Schmidt

All Computer Science and Engineering Research

The Internet Inter-ORB Protocol (IIOP) enables heterogeneous CORBA-compliant Object Request Brokers (ORBs) to interoperate over TCP/IP networks. The IIOP uses the Common Data Representation (CDR) transfer syntax to map CORBA Interface Definition Langauge (IDL) data types into a bi-canonical wire format. Due to the excessive marshaling/demarshaling overhead, data copying, and high-levels of function call overhead, conventional implementation of IIOP protocols yield poor performance over high-speed networks. To meet the demands of emerging distributed multimedia applications, CORBA-compliant ORBs must support both interoperable and highly efficient IIOP implementations. This paper provides two contributions to the study and design of high performance CORBA …

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Eliding The Arguments Of Cases, Ronald P. Loui, Jeff Norman Jan 1997

Eliding The Arguments Of Cases, Ronald P. Loui, Jeff Norman

All Computer Science and Engineering Research

No abstract provided.

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Euphoria Reference Manual, T. Paul Mccartney, Kenneth J. Goldman Jan 1997

Euphoria Reference Manual, T. Paul Mccartney, Kenneth J. Goldman

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EUPHORIA is a user interface management system that enables end-users to create direct manipulation graphical user interfaces (GUIs) through interactive drawing. Used in conjunction with The Programmers' Playground, a distributed programming environment, end-users can dynamically create and associate GUI components with an underlying application without programming, This document describes EUPHORIA's functionality.

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Exact Learning Of Discretized Geometric Concepts, Nader H. Bshouty, Paul W. Goldberg, Sally A. Goldman, H. David Mathias Jan 1997

Exact Learning Of Discretized Geometric Concepts, Nader H. Bshouty, Paul W. Goldberg, Sally A. Goldman, H. David Mathias

All Computer Science and Engineering Research

We first present an algorithm that uses membership and equivalence queries to exactly identify a discretized geometric concept defined by the unioin of m axis-parallel boxes in d-dimensional discretized Euclidean space where each coordinate can have n discrete values. This algorithm receives at most md counterexamples and uses time and membership queries polynomial in m and log(n) for any constant d. Furthermore, all equivalence queries can be formulated as the union of O(mdlog(m)) axis-parallel boxes. Next, we show how to extend our algorithm to efficiently learn, from only equivalence queries, any discretized geometric concept generated from any number of halfspaces …

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Noise-Tolerant Parallel Learning Of Geometric Concepts, Nader H. Bshouty, Sally A. Goldman, H. David Mathias Jan 1997

Noise-Tolerant Parallel Learning Of Geometric Concepts, Nader H. Bshouty, Sally A. Goldman, H. David Mathias

All Computer Science and Engineering Research

We present several efficient parallel algorithms for PAC-learning geometric concepts in a constant-dimensional space. The algorithms are robust even against malicious classification noise of any rate less than 1/2. We first give an efficient noise-tolerant parallel algorithm to PAC-learn the class of geometric concepts defined by a polynomial number of (d-1)-dimensional hyperplanes against an arbitrary distribution where each hyperplane has a slope from a set of known slopes. We then describe how boosting techniques can be used so that our algorithms' dependence on {GREEK LETTER} and {DELTA} does not depend on d. Next we give an efficient noise-tolerant parallel algorithm …

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An Error Control Scheme For Large-Scale Multicast Applications, Christos Papadopoulos, Guru Parulkar, George Varghese Jan 1997

An Error Control Scheme For Large-Scale Multicast Applications, Christos Papadopoulos, Guru Parulkar, George Varghese

All Computer Science and Engineering Research

Retransmission based error control for large scale multicast applications is difficult because of two main problems: request implosion and lack of local recovery. Existing schemes (SRM, RMTP, TMTP, LBRRM) have good solutions to request implosion, but only approximate solutions (e.g., based on scoped multicast) for the local recovery problem. Our scheme achieves finer grain fault recovery by exploiting new forwarding services that allow us to create a dynamic hierarchy of receivers. We use a new paradigm, where routers provide a more refined form of multicasting (that may be useful to other applications), that enables local recovery. The new services, however, …

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Reducing Web Latencies Using Precomputed Hints, Girish P. Chandranmenon, George Varghese Jan 1997

Reducing Web Latencies Using Precomputed Hints, Girish P. Chandranmenon, George Varghese

All Computer Science and Engineering Research

Current network technology is bandwidth-rich but latency-poor; thus round-trip delays will dominate access latency for web traffic. We describe four new techniques that reduce the round-trips needed for web accesses. The techniques are based on the paradigm of preprocessing a web page to collect information about links and inline data in the page. Stored Address Binding almost always eliminates the DNS lookup (which can cost seconds) at the start of a transaction. In Informed Server Proxying, a server tells its client that it has cached pages referenced in a page the client just retrieved; this allows the client to retrieve …

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Cappucino: An Extensible Planning Tool For Constraint-Based Atm Network Design, Inderjeet Singh, Jonathan S. Turner Jan 1997

Cappucino: An Extensible Planning Tool For Constraint-Based Atm Network Design, Inderjeet Singh, Jonathan S. Turner

All Computer Science and Engineering Research

Cappuccino is a planning tool for topological design of ATM networks. It uses a novel constraint-based approach to ATM network design. Extensibility of the tool is a basic design goal and the tool provides an open interface to incorporate new algorithms.

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Dynamic Flow Switching: A New Communication Service For Atm Networks, Qiyong Bian, Kohei Shimoto, Jonathan Turner Jan 1997

Dynamic Flow Switching: A New Communication Service For Atm Networks, Qiyong Bian, Kohei Shimoto, Jonathan Turner

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This paper presents a new communication service for ATM networks that provides one-way, adjustable rate, on-demand communication channels. The proposed dynamic flow service is designed to operate within a multi-service cell switched network that supports both conventional switched virtual circuits and IP packet routing and is designed to complement those services. It is particularly well suited to applications that transmit substantial amounts of data (a few tens of kilobytes or more) in fairly short time periods (up to a few seconds). Much of the current world-wide web traffic falls within this domain. Like IP packet networks, the new service permits …

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Replication Of The First Controlled Experiment On The Usefulness Of Design Patterns: Detailed Description And Evaluation, Lutz Prechelt, Barbara Unger, Douglas Schmidt Jan 1997

Replication Of The First Controlled Experiment On The Usefulness Of Design Patterns: Detailed Description And Evaluation, Lutz Prechelt, Barbara Unger, Douglas Schmidt

All Computer Science and Engineering Research

Advocates of software design patterns claim that using design patterns improves communication between software developers. The controled experiment that we describe in this report tests the hypothesis that software maintainers of well-structured, well-documented software containing design patterns can make changes (1) faster and (2) with less errors if the use of patterns is explicitly documented in the software. The experiment was performed with 22 participants of a university course on C++ and design patterns; it is similar to a previous experiment performed in Karlsruhe. For one of the two experiment tasks the experiment finds that both hypotheses appear to be …

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