Digital Commons Network^™

Pythia: A Knowledge Based System For Intelligent Scientific Computing, Sanjiva Weerawarana, Elias N. Houstis, John R. Rice, Anupam Joshi, Catherine E. Houstis

Department of Computer Science Technical Reports

No abstract provided.

On Learning And Adaptation In Multiagent Systems: A Scientific Computing Perspective, Anupam Joshi, Tzvetan Drashansky, John R. Rice, Sanjiva Weerawarana, Elias N. Houstis

Department of Computer Science Technical Reports

No abstract provided.

Neural And Neuro-Fuzzy Approaches To Support ``Intelligent'' Scientific Problem Solving, Anupam Joshi, Sanjiva Weerawarana, Narendran Ramakrishnan, Elias N. Houstis, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

The Forward-Backward Asymmetry For Charm Quarks At The Z Pole, D. Buskulic, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

From 1.4 million hadronic Z decays collected by the ALEPH detector at LEP, an enriched sample of Z → cc̄ events is extracted by requiring the presence of a high momentum D∗±. The charm quark forward-backward charge asymmetry at the Z pole is measured to be AFB0.c = (8.0 ± 2.4) % corresponding to an effective electroweak mixing angle of sin2θWeff = 0.2302 ± 0.0054.

Hodographs And Normals Of Rational Curves And Surfaces, Thomas W. Sederberg, Takafumi Saito, Guo-Jin Wang

Faculty Publications

Derivatives and normals of rational Bézier curves and surface patches are discussed. A non-uniformly scaled hodograph of a degree m x n tensor-product rational surface, which provides correct derivative direction but not magnitude, can be written as a degree (2m - 2) x 2n or 2m x (2n - 2) vector function in polynomial Bézier form. Likewise, the scaled normal direction is degree (3m - 2) x(3n - 2). Efficient methods are developed for bounding these directions and the derivative magnitude.

Document Preprocessing And Fuzzy Unsupervised Character Classification, Shy-Shyan Chen

Dissertations

This dissertation presents document preprocessing and fuzzy unsupervised character classification for automatically reading daily-received office documents that have complex layout structures, such as multiple columns and mixed-mode contents of texts, graphics and half-tone pictures. First, the block segmentation algorithm is performed based on a simple two-step run-length smoothing to decompose a document into single-mode blocks. Next, the block classification is performed based on the clustering rules to classify each block into one of the types such as text, horizontal or vertical lines, graphics, and pictures. The mean white-to-black transition is shown as an invariance for textual blocks, and is useful …

Visual Pattern Recognition Using Neural Networks, Jenlong Moh

Dissertations

Neural networks have been widely studied in a number of fields, such as neural architectures, neurobiology, statistics of neural network and pattern classification. In the field of pattern classification, neural network models are applied on numerous applications, for instance, character recognition, speech recognition, and object recognition. Among these, character recognition is commonly used to illustrate the feature and classification characteristics of neural networks.

In this dissertation, the theoretical foundations of artificial neural networks are first reviewed and existing neural models are studied. The Adaptive Resonance Theory (ART) model is improved to achieve more reasonable classification results. Experiments in applying the …

Ph.D. Thesis Proprosal: Transportable Agents, Robert S. Gray

Computer Science Technical Reports

One of the paradigms that has been suggested for allowing efficient access to remote resources is transportable agents. A transportable agent is a named program that can migrate from machine to machine in a heterogeneous network. The program chooses when and where to migrate. It can suspend its execution at an arbitrary point, transport to another machine and resume execution on the new machine. Transportable agents have several advantages over the traditional client/server model. Transportable agents consume less network bandwidth and do not require a connection between communicating machines -- this is attractive in all networks and particularly attractive in …

A Domain-Specific Parallel Programming System Ii. Automatic Data Partitioning, Elaine Wenderholm

Electrical Engineering and Computer Science - Technical Reports

εm is a high-level programming system which puts parallelism within the reach of scientists who are not sophisticated programmers. εm both restricts and simplifies the programming interface, and thereby eases both the conceptual task of the programmer and the analytical task of the compiler. The εm compiler performs automatic data structure definition, scheduling and data partitioning. This document presents the automatic data partitioning algorithm used in εm.

Software Testing Paradigms, A. Subramaniam, G. Zobrist

Computer Science Technical Reports

The development of software follows a series of steps adopted from the Classical Life Cycle approach. Amongst all the steps, Software testing demands a lot of attention considering the amount of effort applied in it. There are various techniques by which a software can be tested. A review of techniques available are discussed. A methodology that can be applied to software testing has also been suggested. This document can be used by a programmer to select the technique for software testing and also assists in providing a narrowed view to the vast number of techniques available for software testing.

Discovery Of Integrity Relationships In Relational Databases, D. Harrier, D. C. St. Clair

Computer Science Technical Reports

The use of database management system integrity constraints has been a powerful tool in raising the quality of data within an application subject database. Unfortunately, the successful use of integrity constraints requires that the database administrator has implemented the constraint before data are inserted into the database.

The results of this research provide a methodology for discovering previously unknown integrity relationships in a relational database. The methodology uses the principles of knowledge discovery from the artificial intelligence community, and Quinlan's ID3 machine learning algorithm as the discovery tool. Experimental results are provided that demonstrate how the methodology can be applied.

A Meta-Interpreter For Circuit-Extraction, Krishnaprasad Thirunarayan

Kno.e.sis Publications

The design of a VLSI circuit consists of a description of the circuit in terms of its components and subcomponents, at various levels of detail. To verify that the layout of a VLSI circuit conforms to its design, one needs to work backwards from the lowest-level description of the circuit and recognize the higher-level components it constitutes. This paper is concerned with the application of logic programming techniques in the formal verification of the structural correctness of the VLSI circuit layouts. In particular, we review Michael Dukes' Generalized Extraction System (1990) that compiles design descriptions into a set of extraction …

On The Distribution For The Duration Of A Randomized Leader Electron Algorithm, James Allen Fill, Hosam M. Mahmoud, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

The Effect Of A Database Feedback System On User Performance, H. Chan, K. Wei, Keng Siau

Research Collection School Of Computing and Information Systems

There are two main approaches to improving the effectiveness of database interfaces. One is to raise the level of abstraction for the content of the user-database interaction. The relational model belonging to the logical level has replaced the hierarchical and network models that belong to the lower physical level. It is likely that the relational model will eventually be replaced by models belonging to the even higher conceptual level, such as entity relationship models and object-oriented models. The second approach is to enhance the actual interaction process. This can be done by providing better feedback to the user. Feedback can …

Myriad: Design And Implementation Of A Federated Database Prototype, Ee Peng Lim, San-Yih Hwang, Jaideep Srivastava, Dave Clements, M. Ganesh

Research Collection School Of Computing and Information Systems

A key problem in providing enterprise-wide information is the integration of databases that have been independently developed. An important requirement is to accommodate heterogeneity and maintain the autonomy of component databases. Myriad is a federated database prototype developed at the University of Minnesota, to provide a testbed for investigating alternatives in architecture and algorithms for database integration, query processing and optimization, and concurrency control and recovery. The system incorporates our group's research results in these areas. This paper describes our experiences in the design and implementation of Myriad, and in the project management. Special emphasis is given to discussing design …

Mist: Pvm With Transparent Migration And Checkpointing, Jeremy Casas, Dan Clark, Phil Galbiati, Ravi Konuru, Steve Otto, Robert Prouty, Jonathan Walpole

Computer Science Faculty Publications and Presentations

We are currently involved in research to enable PVM to take advantage of shared networks of workstations (NOWs) more effectively. In such a computing environment, it is important to utilize workstations unobtrusively and recover from machine failures. Towards this goal, we have enhanced PVM with transparent task migration, checkpointing, and global scheduling. These enhancements are part of the MIST project which takes an open systems approach in developing a cohesive, distributed parallel computing environment. This open systems approach promotes plug-and-play integration of independently developed modules, such as Condor, DQS, A VS, Prospero, XPVM, PIOUS, Ptools, etc. Transparent task migration, in …

From Formal Security Specifications To Executable Assertions - A Distributed Systems Preliminary Study, C. Serban, B. Mcmillin

Computer Science Technical Reports

A security policy for a distributed system can be checked for compliance at run-time, as the system executes, using assertions embedded in software. This paper presents the concept of run-time security assurance, according to a given security policy for a given distributed system, along with mechanisms for its usage. A model problem illustrates the implementation of executable security assertions and their run-time validation on histories (traces) of events.

Cognitive Cooperation Through Visual Interaction, Erika Rogers

Computer Science and Software Engineering

The purpose of the paper is to describe a cooperative system which was designed to provide intelligent assistance in the domain of diagnostic radiology. The approach taken includes the collection and analysis of human performance data, cognitive modelling of the interaction between perception and problem solving. incorporation of this knowledge into a blackboard-based architecture. implementation of a prototype system and testing and evaluation of the prototype. These stages are described, and then discussed in the context of issues particularly relevant to the study of human-machine cooperation.

Evolving Globally Synchronized Cellular Automata, Rajarshi Das, James P. Crutchfield, Melanie Mitchell, James M. Hanson

Computer Science Faculty Publications and Presentations

How does an evolutionary process interact with a decentralized, distributed system in order to produce globally coordinated behavior? Using a genetic algorithm (GA) to evolve cellular automata (CAs), we show that the evolution of spontaneous synchronization, one type of emergent coordination, takes advantage of the underlying medium's potential to form embedded particles. The particles, typically phase defects between synchronous regions, are designed by the evolutionary process to resolve frustrations in the global phase. We describe in detail one typical solution discovered by the GA, delineating the discovered synchronization algorithm in terms of embedded particles and their interactions. We also use …

Arbitrary Topology Shape Reconstruction From Planar Cross Sections, Chandrajit L. Bajaj, Edward J. Coyle, Kwun-Nan Lin

Department of Computer Science Technical Reports

No abstract provided.

Sciagents--An Agent Based Environment For Distributed, Cooperative Scientific Computing, Tzvetan T. Drashansky, Anupam Joshi, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

Adaptive Reconstruction Of Surfaces And Scalar Fields From Dense Scattered Trivariate Data, Chandrajit L. Bajaj, Fasuto Bernardini, Guoliang Xu

Department of Computer Science Technical Reports

No abstract provided.

Error-Bounded Reduction Of Triangle Meshes With Multivariate Data, Chandrajit L. Bajaj, Daniel R. Schikore

Department of Computer Science Technical Reports

No abstract provided.

Rational Parametrizations Of Real Cubic Surfaces, Chandrajit L. Bajaj, Robert J. Holt, Arun N. Netravali

Department of Computer Science Technical Reports

No abstract provided.

Exceptions And Exception Handling In Computerized Information Processes, Diane M. Strong, Steven M. Miller

Research Collection School Of Computing and Information Systems

Exceptions, situations that cannot be correctly processed by computer systems, occur frequently in computer-based information processes. Five perspectives on exceptions provide insights into why exceptions occur and how they might be eliminated or more efficiently handled. We investigate these perspectives using an in-depth study of an operating information process that has frequent exceptions. Our results support the use of a total quality management (TQM) approach of eliminating exceptions for some exceptions, in particular, those caused by computer systems that are poor matches to organizational processes. However, some exceptions are explained better by a political system perspective of conflicting goals between …

An Upper Limit For The Τ Neutrino Mass From Τ → 5Π(Π0)Ντ Decays, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

From a sample of 152,000 τ decays collected by the ALEPH detector at LEP an upper limit of 24 MeV at 95% CL on the τ neutrino mass has been determined. The limit is obtained using a two dimensional likelihood fit of the visible energy and the invariant mass distribution of 25 τ → 5π(π0)ντ events.

Open-Loop State-Space Model Identification From Closed-Loop Data, Lori Guy

Mechanical & Aerospace Engineering Theses & Dissertations

This thesis provides an investigation of a system identification algorithm which identifies an open-loop state-space model from a linear system that is operating under closed-loop conditions. In order to investigate the system identification algorithm some basic ideas of system identification theory are reviewed. Examples using simulated data are presented to characterize the effects of varying the parameters for open-loop and closed-loop system identification processes. Both noise· free and noise contaminated cases are simulated. Linear Quadratic Gaussian (LQG) control theory is reviewed and the motivation for using iterative LQG control feedback is discussed. The derivation of the proposed system identification algorithm …

Generalization Metrics For Neural Modeling Applications In System Identification, Denise M. Reeves

Electrical & Computer Engineering Theses & Dissertations

In this thesis a procedure to design multilayer feedforward networks for system identification with good prediction properties is presented. Central to the design procedure is a means to characterize the prediction capabilities of various trained neural networks. Such knowledge will allow for the identification of the best network design. For system identification purposes, a "good" model is one that is good at predicting, In particular, a good model is one that produces small prediction errors when applied to a set of cross-validation data. We formulate and implement a criterion function designed to measure the size of a trained neural network's …

Mpvm: A Migration Transparent Version Of Pvm, Jeremy Casas, Dan Clark, Ravi Konuru, Steve Otto, Robert Prouty, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Parallel Virtual Machine (PVM) is a widely-used software system that allows a heterogeneous set of parallel and serial UNIX-based computers to be programmed as a single message-passing parallel machine, In this paper, an extension to PVM to support dynamic process migration is presented. Support for migration is important in general-purpose workstation environments since it allows parallel computations to co-exist with other applications, using idle-cycles as they become available and off-loading from workstations when they are no longer free. A description and evaluation of the design and implementation of the prototype Migratable PVM system is presented together with some performance results.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 11, Number 3, March 1995, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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