Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Computer Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 60361 - 60390 of 63876

Full-Text Articles in Entire DC Network

Irregular Personalized Communication On Distributed Memory Machines, Sanjay Ranka, Jhy-Chun Wang Jan 1995

Irregular Personalized Communication On Distributed Memory Machines, Sanjay Ranka, Jhy-Chun Wang

College of Engineering and Computer Science - Former Departments, Centers, Institutes and Projects

In this paper we present several algorithms for performing all-to-many personalized communication on distributed memory parallel machines. We assume that each processor sends a different message (of potentially different size) to a subset of all the processors involved in the collective communication. The algorithms are based on decomposing the communication matrix into a set of partial permutations. We study the effectiveness of our algorithms both from the view of static scheduling and from runtime scheduling.

Go to article

Knowledge-Based Image Enhancement For Cooperative Tele-Assistance, Erika Rogers, Versonya Dupont, Robin R. Murphy, Nazir Warsi Jan 1995

Knowledge-Based Image Enhancement For Cooperative Tele-Assistance, Erika Rogers, Versonya Dupont, Robin R. Murphy, Nazir Warsi

Computer Science and Software Engineering

There is an increasing need in complex environments for computerized assistance, both for the effective filtering and display of pertinent information or data, and also for the decision-making task itself. The combination of artificial intelligence techniques with image processing and graphics capabilities provides the foundation for building intelligent systems which act as mediaries between the human and the task domain. In the field of tele-assistance, this type of system enables cooperative problem-solving between a remote semi-autonomous robot and a local human supervisor. This paper describes current work on such a system, with an emphasis on the development of knowledge-based image …

Go to article

Cooperative Assistance For Remote Robot Supervision, Erika Rogers, Robin R. Murphy, A. Stewart, Nazir Warsi Jan 1995

Cooperative Assistance For Remote Robot Supervision, Erika Rogers, Robin R. Murphy, A. Stewart, Nazir Warsi

Computer Science and Software Engineering

This paper describes current work on the design of a computer system which provides cooperative assistance for the supervision of remote semi-autonomous robots. It consists of a blackboard-based framework which allows communication between the remote robot, the local human supervisor, and an intelligent mediating system, which aids interactive exception handling when the remote robot requires the assistance of the local operator.

Go to article

A Cognitive Theory Of Visual Interaction, Erika Rogers Jan 1995

A Cognitive Theory Of Visual Interaction, Erika Rogers

Computer Science and Software Engineering

No abstract provided.

Go to article

Scis Networking - January 1995, Nova Southeastern University - Shepard Broad College Of Law Jan 1995

Scis Networking - January 1995, Nova Southeastern University - Shepard Broad College Of Law

CCIS Networking / SCIS Networking magazines

No abstract provided.

Go to article

Finiteness Of The Fixed Point Set For The Simple Genetic Algorithm, Alden H. Wright, Michael D. Vose Jan 1995

Finiteness Of The Fixed Point Set For The Simple Genetic Algorithm, Alden H. Wright, Michael D. Vose

Computer Science Faculty Publications

The infinite population simple genetic algorithm is a discrete dynamical system model of a genetic algorithm. It is conjectured that trajectories in the model always converge to fixed points. This paper shows that an arbitrarily small perturbation of the fitness will result in a model with a finite number of fixed points. Moreover, every sufficiently small perturbation of fimess preserves the finiteness of the fixed point set. These results allow proofs and constructions that require finiteness of the fixed point set. For example, applying the stable manifold theorem to a fixed point requires the hyperbolicity of the differential of the …

Go to article

Mathematical And Theological Beliefs: A Cognitive Science Perspective, Ron Benbow Jan 1995

Mathematical And Theological Beliefs: A Cognitive Science Perspective, Ron Benbow

ACMS Journal 2004

In recent years, research studies have shown that control decisions and processes, beliefs about the nature of mathematics, attitudes, and other affective variables have enormous impact on the mathematical performance of students. This paper gives an overview of the research on mathematical beliefs and reviews some work done in Christian education relating to theological beliefs. It then compares the two.

Go to article

Mathematics From The Viewpoint Of Science In Context, Johan Deklerk Jan 1995

Mathematics From The Viewpoint Of Science In Context, Johan Deklerk

ACMS Journal 2004

This is the first of a series of papers presented over several years by deKlerk exploring the notion of how mathematics might be taught from a Christian perspective. In this paper, he introduces the notion of context as the basis for such an approach. He then discusses seven contexts a teacher can employ.

Go to article

Communication-Efficient And Memory-Bounded External Redistribution, Jang Sun Lee, Sanjay Ranka, Ravi V. Shankar Jan 1995

Communication-Efficient And Memory-Bounded External Redistribution, Jang Sun Lee, Sanjay Ranka, Ravi V. Shankar

College of Engineering and Computer Science - Former Departments, Centers, Institutes and Projects

This paper presents communication-efficient algorithms for the external data redistribution problem. Deterministic lower bounds and upper bounds are presented for the number of I/O operations, communication time and the memory requirements of external redistribution. Our algorithms differ from most other algorithms presented for out-of-core applications in that it is optimal (within a small constant factor) not only in the number of I/O operations, but also in the time taken for communication. A coarse-grained MIMD architecture with I/O subsystems attached to each processor is assumed, but the results are expected to be applicable over a wider variety of architectures.

Go to article

A System For Recognizing A Large Class Of Engineering Drawings, Yuhong Yu, Ashok Samal, Sharad C. Seth Jan 1995

A System For Recognizing A Large Class Of Engineering Drawings, Yuhong Yu, Ashok Samal, Sharad C. Seth

School of Computing: Conference and Workshop Papers

We present a complete system for recognizing a large class of symbolic engineering drawings that includes flowcharts, chemical plant diagrams, and logic & electrical circuits. The output of the system, a netlist identifying the symbol types and interconnections, may be used for design verification or as a compact portable representation of the drawing. The automatic recognition task is done in two stages: (1) domain-independent rules segment symbols from connection lines in the preprocessed drawing image and (2) an understanding subsystem makes use of a set of domain-specific matchers to classify symbols and correct errors automatically. A graphical user interface is …

Go to article

Runtime And Language Support For Compiling Adaptive Irregular Programs On Distributed Memory Machines, Yuan-Shin Hwang, Bongki Moon, Shamik D. Sharma, Ravi Ponnusamy Jan 1995

Runtime And Language Support For Compiling Adaptive Irregular Programs On Distributed Memory Machines, Yuan-Shin Hwang, Bongki Moon, Shamik D. Sharma, Ravi Ponnusamy

Northeast Parallel Architecture Center

In many scientific applications, arrays containing data are indirectly indexed through indirection arrays. Such scientific applications are called irregular programs and are a distinct class of applications that require special techniques for parallelization. This paper presents a library called CHAOS, which helps users implement irregular programs on distributed-memory message-passing machines, such as the Paragon, Delta, CM-5 and SP-1. The CHAOS library provides efficient runtime primitives for distributing data and computation over processors; it supports efficient index translation mechanisms and provides users high-level mechanisms for optimizing communication. CHAOS subsumes the previous PARTI library and supports a larger class of applications. In …

Go to article

Nonrecursive Incremental Evaluation Of Datalog Queries, Guozhu Dong, Jianwen Su, Rodney Topor Jan 1995

Nonrecursive Incremental Evaluation Of Datalog Queries, Guozhu Dong, Jianwen Su, Rodney Topor

Kno.e.sis Publications

We consider the problem of repeatedly evaluating the same (computationally expensive) query to a database that is being updated between successive query requests. In this situation, it should be possible to use the difference between successive database states and the answer to the query in one state to reduce the cost of evaluating the query in the next state. We use nonrecursive Datalog (which are unions of conjunctive queries) to compute the differences, and call this process “incremental query evaluation using conjunctive queries”. After formalizing the notion of incremental query evaluation using conjunctive queries, we give an algorithm that constructs, …

Go to article

Transient Data Sharing Among Mobile Programs, Jerome Plun, Gruia-Catalin Roman Jan 1995

Transient Data Sharing Among Mobile Programs, Jerome Plun, Gruia-Catalin Roman

All Computer Science and Engineering Research

Mobile computing represents a major point of departure from the traditional distributed computing paradigm. The potentially very large number of independent computing units, a decoupled computing style, frequent disconnections, continuous position changes, and the location-dependent nature of the behavior and communication patterns present designers with unprecedented challenges in the areas of modularity and dependability. This paper describes a modular approach to specifying and reasoning about of mobile computing. Its novelty rests with the notion of allowing transient (location-dependent) data sharing among programs which move in space. The notation is a direct extension of that used in UNITY and reasoning about …

Go to article

Hart's Critics On Defeasible Concepts And Ascriptivism, Ronald P. Loui Jan 1995

Hart's Critics On Defeasible Concepts And Ascriptivism, Ronald P. Loui

All Computer Science and Engineering Research

Hart's "Ascription of Responsibility and Rights" is where we find perhaps the first clear pronouncement of defeasibility and the technical introduction of the term. The paper has been criticised, disavowed, and never quite fully redeemed. Its lurid history is now being used as an excuse for dismissing the importance of defeasibility. Quite to the contrary, Hart's introduction of defeasibility has uniformly been regarded as the most agreeable part of the paper. The critics' wish that defeasibility could be better expounded along the lines of a Wittgensteinian game-theoretic semantics has largely been fulfilled. Even the most contentious part of the paper, …

Go to article

Can Declared Strategy Voting Be An Effective Instrument For Group Decision-Making?, Lorrie Faith Cranor Jan 1995

Can Declared Strategy Voting Be An Effective Instrument For Group Decision-Making?, Lorrie Faith Cranor

All Computer Science and Engineering Research

The goal of this research is to determine whether declared strategy voting can be an effective tool for group decision-making. Declared strategy voting is a novel group decision-making procedure in which preference is specified using voting strategies - first-order mathematical functions that specify a choice in terms of zero or more parameters. This research will focus on refining the declared strategy voting concept, developing an accessible implementation of declared strategy voting that can be used for mock elections, assessing the potential impacts of declared strategy voting, and evaluating the effectiveness of declared strategy voting for group decision-making. This proposal describes …

Go to article

A General Matrix Iterative Model For Dynamic Load Balancing, Mark A. Franklin, Vasudha Govindan Jan 1995

A General Matrix Iterative Model For Dynamic Load Balancing, Mark A. Franklin, Vasudha Govindan

All Computer Science and Engineering Research

Effective load balancing algorithms are crucial in fully realizing the performance potential of parallel computer systems. This paper proposes a general matrix iterative model to represent a range of dynamic load balancing algorithms. The model and associated performance measures are used to evaluate and compare vairous load balancing algorithms and derive optimal algorithms and associated parameters for a given application and multiprocessor system. The model is parameterized to represent three load balancing algorithms - the random strategy, diffusion and complete redistribution algorithms. The model is validated by comparing the results with measured performance on a realistic workload. The parallel N-body …

Go to article

A Survey Of Network Signaling, Dakang Wu Jan 1995

A Survey Of Network Signaling, Dakang Wu

All Computer Science and Engineering Research

Abstract Network signaling is the process of transferring control information among components of a communication network to establish, maintain, and release connections, and to pass the network management information. The rapid evolution in the field of telecommunications has led to the rapid evolution of network signaling. In this paper, we review the evolution of network signaling. We emphasize the concepts and protocols used in modern fast packet switching networks especially in emerging ATM networks.

Go to article

Real-Time Upcalls: A Mechanism To Provide Real-Time Processing Guarantees, Raman Gopalakrishna, Guru M. Parulkar Jan 1995

Real-Time Upcalls: A Mechanism To Provide Real-Time Processing Guarantees, Raman Gopalakrishna, Guru M. Parulkar

All Computer Science and Engineering Research

Real-time upcalls (RTUs) are an operating systems mechanism that can be used by applications to efficiently schedule code segments (or handlers) that must execute periodically. While the mechanism was conceibed to support protocol processing with quality-of-service guarantees for networked multimedia applicatoins it is general enough to be applicable in other domains like real-time image processing. Until now real-time threads have been the only mechanism for implementing protocols in user space with QoS guarantees. The RTU mechanism avoids the implementation complexity of the thread based approach while retaining its ability to ensure real-time behavior. In addition, our design simplifies protocol code, …

Go to article

Pac Learing Of One-Dimensional Patterns, Paul W. Goldberg, Sally A. Goldman, Stephen D. Scott Jan 1995

Pac Learing Of One-Dimensional Patterns, Paul W. Goldberg, 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 consider the problem of PAC-learning the concept class of geometric patterns where the target geometric pattern is a configuration of k points on the real line. Each instance is a configuration of n points on the real line, where it is labeled according to whether or not it visually resembles the target pattern. To capture the notion of visual resemblance we use the Hausdorff metric. Informally, two geometric patterns P and Q resemble each othe runder the …

Go to article

Issues In Distributed Control For Atm Networks, Jonathan S. Turner Jan 1995

Issues In Distributed Control For Atm Networks, Jonathan S. Turner

All Computer Science and Engineering Research

Asynchronous Transfer Mode (ATM) network technology is expected to become a central part of the emerging global information infrastructure. ATM networks introduce a number of features that distinguish them from earlier technologies and introduce new issues in network control. This paper offers a framework for precisely defining and analyzing alternative approaches to the distributed control of ATM networks and explores some of the key design issues through a series of examples. It is hoped that it will provide a useful foundation for researchers in networking and distributed computing interested in exploring these issues further and developing more complete solutions.

Go to article

Synchronized Data Objects, Marin Bezic Jan 1995

Synchronized Data Objects, Marin Bezic

All Computer Science and Engineering Research

Synchronized Data Objects (SDOs) are presented as a method of encapsulating, in the datatype definition, synchronization protocols that are used to control information exchange. SDOs are presented in the context of I/O abstraction, a programming model that seeks to separate communication from computation in order to support dynamic end-user configuration of distrivuted applications. SDOs can be used to implement a variety of synchronization paradigms, including remote invalidation, demand-driven data streams, remote procedure call, and promises. An implementation of SDOs is described in the context of The Programmers' Playground, a distributed application development environment that supports the I/O abstraction programming model. …

Go to article

Distributed Debugging With I/O Abstraction, Andrew S. Koransky Jan 1995

Distributed Debugging With I/O Abstraction, Andrew S. Koransky

All Computer Science and Engineering Research

This thesis presents a simple, yet powerful, set of mechanisms for testing and debugging distributed applications consisting of modules that communicate through well-defined data interfaces. The tools allow default or programmer-defined functions to be attached to various communication events so that particular data values at interesting points in the program are made available for testing and debugging. The debugging status of each component of the communication interface can be controlled separately so that various debugging information can be turned on and off during program execution. By attaching breakpoints to programmer-defined fucntions in a standard debugger, fine-grained examination of each module …

Go to article

Formal Specification Of A Dynamically Configurable Distributed System, Ram Sethuraman, Kenneth J. Goldman Jan 1995

Formal Specification Of A Dynamically Configurable Distributed System, Ram Sethuraman, Kenneth J. Goldman

All Computer Science and Engineering Research

The Programmers' Playground is a programming environment that supports end-user construction of distributed multimedia applications. The system implements a new programming model that is based, in part, upon ideas from the formal I/O automaton model of Lynch and Tuttle. Important features of The Programmers' Playground are a separation of communication and computation and graphical support for dynamic reconfiguration. This paper provides a formal specification of the Playground programming model and runtime system in terms of the I/O automaton model on which it is based. Exploiting the compositionality properties of the I/O automaton model, the formal specification is describd as a …

Go to article

Building Interactive Distributed Applications In C++ With The Programmers' Playground, Kenneth J. Goldman, T. Paul Mccartney, Ram Sethuraman, Bala Swaminathan And Todd Rogers Jan 1995

Building Interactive Distributed Applications In C++ With The Programmers' Playground, Kenneth J. Goldman, T. Paul Mccartney, Ram Sethuraman, Bala Swaminathan And Todd Rogers

All Computer Science and Engineering Research

No abstract provided.

Go to article

Redesigning The Bsd Callout And Timer Facilities, Adam M. Costello, George Varghese Jan 1995

Redesigning The Bsd Callout And Timer Facilities, Adam M. Costello, George Varghese

All Computer Science and Engineering Research

We describe a new implementation of the BSD callout and timer facilities. Current BSD kernels take time proportional to the number of outstanding timers to set or cancel timers. Our implementation takes constant time to start, stop, and maintain timers; this leads to a highly scalable design that can support thousands of outstanding timers without much overhead. Unlike the existing implementation, our routines are guaranteed to lock out interrupts only for a small, bounded amount of time. We also extend the setitimer() interface to allow a process to have multiple outstanding timers, thereby reducing the need for users to maintain …

Go to article

User Interface Applications Of A Multi-Way Constraint Solver, T. Paul Mccartney Jan 1995

User Interface Applications Of A Multi-Way Constraint Solver, T. Paul Mccartney

All Computer Science and Engineering Research

Constraints are widely recognized as a useful tool for user interface constructino. Through constraints, relationships among user interface components can be defined declaratively, leaving the task of relationship management to a constraint solver. Multi-way constraint solvers supporting constraint hierarchies provide a means to specify preferential constraint relationships with a dynamically changing computation flow, making them especially well suited to interactive user interfaces. However, previous such constraint solvers lack the ability to enforce inequalities or to effectively handle cyclic constraint relationships. These deficiencies limit the problems that could be solved using a constraint-based approach. This paper presents a new algorithm called …

Go to article

Aras: Asynchronous Risc Architecture Simulator, Chia-Hsing Chien, Mark A. Franklin, Tienyo Pan, Prithvi Prabhu Jan 1995

Aras: Asynchronous Risc Architecture Simulator, Chia-Hsing Chien, Mark A. Franklin, Tienyo Pan, Prithvi Prabhu

All Computer Science and Engineering Research

In this paper, an asynchronous pipeline instruction simulator, ARAS is presented. With this simulator, one can design selected instruction pipelines and check their performance. Performance measurements of the pipeline configuration are obtained by simulating the execution of benchmark programs on the machine architectures developed. Depending on the simulation results obtained by using ARAS, the pipeline configuration can be altered to improve its performance. Thus, one can explore the design space of aynchronous pipeline architectures.

Go to article

Reasoning About Program Interactions In The Presence Of Mobility, Gruia-Catalin Roman, Peter J. Mccann Jan 1995

Reasoning About Program Interactions In The Presence Of Mobility, Gruia-Catalin Roman, Peter J. Mccann

All Computer Science and Engineering Research

Mobile computing is emerging as an important new paradigm which has the potential to reshape our thinking about distributed computation. Mobility has far-reaching implications on what designers and users can assume about communication patterns, resource availability, and applciation behaviors as components move from one location to another while joining or leaving groups of other components in their vicinity. New distributed algorithms are likely to be required as the nature of applications shifts with the emergence of this new kind of computing environment. Formal methods have an important role to play in the midst of these developments both in terms of …

Go to article

Time Variability While Training A Parallel Neural Net Network, Tina L. Seawell, Barry L. Kalman Jan 1995

Time Variability While Training A Parallel Neural Net Network, Tina L. Seawell, Barry L. Kalman

All Computer Science and Engineering Research

The algorithmic analysis, data collection, and statistical analysis required to isolate the cause of time variability observed while an Elman style recurrent neural network is trained in parallel on a twenty processor SPARCcenter 2000 is described in detail. Correlations of system metrics indicate the operating system scheduler or an interaction of kernel processes is the most probable explanation for the variability.

Go to article

Maintaining High Throughput During Overload In Atm Switches, Jonathan S. Turner Jan 1995

Maintaining High Throughput During Overload In Atm Switches, Jonathan S. Turner

All Computer Science and Engineering Research

This report analyzes two popular heuristics for ensuring packet integrity in ATM switching systems. In particular, we analyze the behavior of packet tail discarding, in order to understand how the packet level link efficiency is dependent on the rates of individual virtual circuits and the degre of the imposed overload. In addition, we study early packet discard and show that the queue capacity needed to achieve high efficiency under worst-case conditions grows with the number of virtual circuits and we determine the efficiency obtainable with more limited queue capacities. Using the insights from these analyses, extensions to early packet discard …

Go to article

First Prev Next Last