Digital Commons Network^™

A Precise Measurement Of The Average B Hadron Lifetime, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

An improved measurement of the average b hadron lifetime is performed using a sample of 1.5 million hadronic Z decays, collected during the 1991–1993 runs of ALEPH, with the silicon vertex detector fully operational. This uses the three-dimensional impact parameter distribution of lepton tracks coming from semileptonic b decays and yields an average b hadron lifetime of 1.533 ± 0.013 ± 0.022 ps.

A Unified Tiling Approach For Out-Of-Core Computations, Rajesh Bordawekar, Alok Choudhary, J. Ramanujam, Mahmut Kandemir

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

This paper describes a framework by which an out-of-core stencil program written in a data-parallel language can be translated into node programs in a distributed-memory message-passing machine with explicit I/O and communication. We focus on a technique called Data Space Tiling to group data elements into slabs that can fit into memories of processors. Methods to choose legal tile shapes under several constraints and deadlock-free scheduling of tiles are investigated. Our approach is unified in the sense that it can be applied to both FORALL loops and the loops that involve flow-dependences.

Shape Recognition Using Genetic Algorithms, Ender Ozcan, Chilukuri K. Mohan

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

Shape recognition is a challenging task when shapes overlap, forming noisy, occluded, partial shapes. This paper uses a genetic algorithm for matching input shapes with model shapes described in terms of features such as line segments and angles (extracted using traditional algorithms). The quality of matching is gauged using a measure derived from attributed shape grammars [12, 13]. Preliminary results, using shapes with about 30 features each, are extremely encouraging.

Unsupervised Algorithms For Learning Emergent Spatio-Temporal Correlations, Chaitanya Tumuluri

Electrical Engineering and Computer Science - Technical Reports

Many applications require the extraction of spatiotemporal correlations among dynamically emergent features of non-stationary distributions. In such applications it is not possible to obtain an a priori analytical characterization of the emergent distribution. This paper extends the Growing Cell Structures (GCS) network and presents two novel (GIST and GEST) networks, which combine unsupervised feature-extraction and Hebbian learning, for tracking such emergent correlations. The networks were successfully tested on the challenging Data Mapping problem, using an execution driven simulation of their implementation in hardware. The results of the simulations show the successful use of the GIST and GEST networks for extracting …

The Isomorphism Conjecture Fails Relative To A Random Oracle, Stuart A. Kurtz, Stephen R. Mahaney, James S. Royer

Electrical Engineering and Computer Science - All Scholarship

Berman and Hartmanis [BH77] conjectured that there is a polynomialtime computable isomorphism between any two languages complete for NP with respect to polynomial-time computable many-one (Karp) reductions. Joseph and Young [JY85] gave a structural definition of a class of NP-complete sets---the k-creative sets---and defined a class of sets (the K k f 's) that are necessarily k-creative. They went on to conjecture that certain of these K k f 's are not isomorphic to the standard NP-complete sets. Clearly, the Berman--Hartmanis and Joseph--Young conjectures cannot both be correct. We introduce a family of strong one-way functions, the scrambling functions. If …

Hierarchical Control Flow Graph Models, Douglas G. Fritz, Robert G. Sargent

Electrical Engineering and Computer Science - All Scholarship

Hierarchical Control Flow Graph Models define a modeling paradigm for discrete event simulation modeling based upon hierarchical extensions to Control Flow Graph Models. Conceptually, models consist of a set of encapsulated, concurrently operating model components that interact solely via message passing. The primary objectives of Hierarchical Control Flow Graph Models are: (1) to facilitate model development by making it easier to develop, maintain, and reuse models and model elements, and (2) to support the flexible and efficient execution of models. Hierarchical Control Flow Graph Models use two complementary types of hierarchical model specification structures, one to specify components and their …

Tests Of Random Number Generators Using Ising Model Simulations, Paul D. Coddington

Northeast Parallel Architecture Center

Large-scale Monte Carlo simulations require high-quality random number generators to ensure correct results. The contrapositive of this statement is also true – the quality of random number generators can be tested by using them in large-scale Monte Carlo simulations. We have tested many commonly used random number generators with high precision Monte Carlo simulations of the 2-d Ising model using the Metropolis, Swendsen-Wang, and Wolff algorithms. This work is being extended to the testing of random number generators for parallel computers. The results of these tests are presented, along with recommendations for random number generators for high-performance computers, particularly for …

Hierarchical Growing Cell Structures, Vanco Burzevski, Chilukuri K. Mohan

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

We propose a hierarchical self-organizing neural network ("HiGS") with adaptive architecture and simple topological organization. This network combines features of Fritzke's Growing Cell Structures and traditional hierarchical clustering algorithms. The height and width of the tree structure depend on the user-specified level of error desired, and the weights in upper layers of the network do not change in later phases of the learning algorithm. Parameters such as node deletion rate are adaptively modified by the learning algorithm.

Cooperative Assistance For Remote Robot Supervision, Robin R. Murphy, Erika Rogers

Computer Science and Software Engineering

This paper describes current work on a cooperative tele-assistance system for semi-autonomous control of mobile robots. This system combines a robot architecture for limited autonomous perceptual and motor control with a knowledge-based operator assistant which provides strategic selection and enhancement of relevant data. It extends recent developments in artificial intelligence in modeling the role of visual interactions in problem solving for application to an interface permitting the human and remote to cooperate in cognitively demanding tasks such as recovering from execution failures, mission planning, and learning. The design of the system is presented, together with a number of exception-handling scenarios …

A Study Of Visual Reasoning In Medical Diagnosis, Erika Rogers

Computer Science and Software Engineering

The purpose of this paper is to describe experimental work conducted in the area of diagnostic radiology,with an emphasis on how perception and problem solving interact in this type of task. This work was part of a larger project whose goals included the development of an information-processing model of visual interaction,and the subsequent design of an intelligent cooperative assistant for this domain.

Verbal protocol data was collected from eight radiologists (six residents and two experts) while they examined seven different computer-displayed chest x-rays. A brief overview of the methodology and analysis techniques is presented, together with specific results from one …

Torus Routing In The Presence Of Multicasts, Hiroki Ishibashi

Theses Digitization Project

No abstract provided.

Technical-Legal Aspects Of Software Patents, Kenneth Nolan Nichols

Theses Digitization Project

No abstract provided.

Syllogism Solving Under Time Pressure, Gondy Leroy, Koen Lamberts

CGU Faculty Publications and Research

No abstract provided.

Compile-Time Performance Prediction Of Hpf/Fortran 90d, Manish Parashar, Salim Hariri

Electrical Engineering and Computer Science - All Scholarship

In this paper we present an interpretive approach for accurate and cost-effective performance prediction in a high performance computing environment, and describe the design of a compile-time HPF/Fortran 90D performance prediction framework based on this approach. The performance prediction framework has been implemented as a part of the HPF/Fortran 90D application development environment that integrates it with a HPF/Fortran 90D compiler and a functional interpreter. The current implementation of the environment framework is targeted to the iPSC/860 hypercube multicomputer system. A set of benchmarking kernels and application codes have been used to validate the accuracy, utility, and usability of the …

Snap, Crackle, Webwindows!, Geoffrey C. Fox, Wojtek Furmanski

Northeast Parallel Architecture Center

We elaborate the SNAP---Scalable (ATM) Network and (PC) Platforms---view of computing in the year 2000. The World Wide Web will continue its rapid evolution, and in the future, applications will not be written for Windows NT/95 or UNIX, but rather for WebWindows with interfaces defined by the standards of Web servers and clients. This universal environment will support WebTop productivity tools, such as WebWord, WebLotus123, and WebNotes built in modular dynamic fashion, and undermining the business model for large software companies. We define a layered WebWindows software architecture in which applications are built on top of multi-use services. We discuss …

Improving Circuit Testability By Clock Control, Kent L. Einspahr, Sharad C. Seth, Vishwani D. Agrawal

School of Computing: Conference and Workshop Papers

The testability of a sequential circuit can be improved by controlling the clocks of individual storage elements during testing. We propose several clock control strategies derived from an analysis of the circuit, its S-graph structure, and its function. Through examples we show how the number of clocks affects the circuit’s testability. It is shown that if certain flip-flops (FFs) are scanned (or otherwise initialized), the remaining FFs can be controlled and initialized to any arbitrary state using the clock control. We derive a controllability graph and use it to assign clocks to FFs and to schedule the clocks to set …

Volunteer Water Quality Monitoring Programs: An Assessment Of Public Participation As A Means Of Fostering Environmental Stewardship, Christopher Damon

Marine Affairs Theses and Major Papers

Volunteer water quality monitoring organizations from across the country were surveyed (n=516) to determine the relationship between public involvement and the generation of stewardship within the community. Program coordinators were asked first to rate the level of stewardship values within the community, and then respond to questions covering four broad areas of public involvement: pre-existing conditions, public education, volunteer behavior, and communal involvement. For each question, organizations were aggregated by response, and a frequency analysis was performed to discover the most common responses in each of the four public involvement categories. the mean of perceived stewardship values was graphed as …

Analogy-Making: A Connectionist Exploration, Doug Blank

Computer Science Faculty Research and Scholarship

No abstract provided.

Information Systems In Non-Profit Organizations: Enhancing Performance Through Online Help, Robert H. Lane

CCAC Theses and Dissertations

The purpose of this dissertation is to focus attention on the problems which non-profit organizations face in dealing with employee dissatisfaction and turnover among clerical staff whose principal responsibility is data entry. To address the problem, a presentation on the background, a discussion of the managerial and information systems implications, and an end-user needs assessment culminated in the development of an online help system for an IDM AS/400-based membership management package.

The system enables the data entry staff to easily locate the answers to most of their commonly asked questions without leaving their workstation, thus reducing the need for as …

An Assessment Of Asynchronous Transfer Mode (Atm) Training For Educators, Dan A. Niswander

CCAC Theses and Dissertations

The purpose of this dissertation was to develop and evaluate a hypertext-based training tutorial/guide on asynchronous transfer mode (ATM) technology for use by school district educators and technology planners. A review of literature indicated training needs on new broadband technologies were not being adequately met from the point of view of an educational environment. An interactive hypertext solution was proposed, designed, and developed based on the needs of adult learners. An analysis of these needs indicated adults prefer flexibility in navigating between training topics as well as in the pace of material presentation, that is, whether to proceed at a …

An Application Perspective On High-Performance Computing And Communications, Geoffrey C. Fox

Northeast Parallel Architecture Center

We review possible and probable industrial applications of HPCC focusing on the software and hardware issues. Thirty-three separate categories are illustrated by detailed descriptions of five areas -- computational chemistry; Monte Carlo methods from physics to economics; manufacturing; and computational fluid dynamics; command and control; or crisis management; and multimedia services to client computers and settop boxes. The hardware varies from tightly-coupled parallel supercomputers to heterogeneous distributed systems. The software models span HPF and data parallelism, to distributed information systems and object/data flow parallelism on the Web. We find that in each case, it is reasonably clear that "HPCC works …

Design And Implementation Of A Practical Security-Conscious Electronic Polling System, Lorrie Faith Cranor, Ron K. Cytron

All Computer Science and Engineering Research

We present the design and implementation of Sensus, a practical, secure and private system for conducting surveys and elections over computer networks. Expanding on the work of Fujioka, Okamoto, and Ohta, Sensus uses blind signatures to ensure that only registered voters can vote and that each registered voter only votes once, while at the same time maintaining voters' privacy. Sensus allows voters to verify independently that their votes were counted correctly, and anonymously challenge the results should their votes be miscounted. We outline seven desirable properties of voting systems and show that Sensus satisfied these properties well, in some cases …

Finding Paths In The Rotation Graph Of Binary Trees, Rodney O. Rogers

Retrospective Theses and Dissertations

A binary tree coding scheme is a bijection mapping a set of binary trees to a set of integer tuples called codewords. One problem considered in the literature is that of listing the codewords for n-node binary trees, such that successive codewords represent trees differing by a single rotation, a standard operation for rebalancing binary search trees. Then, the codeword sequence corresponds to an Hamiltonian path in the rotation graph R_n of binary trees, where each node is labelled with an n-node binary tree, and an edge connects two nodes when their trees differ by a …

Application Of Autoregressive Moving Average Linear Prediction Filters To The Characterization Of Solar Wind-Magnetosphere Coupling, Carter N. Borst

Theses and Dissertations

Linear prediction filtering techniques have been used in studying the coupling processes between the solar wind and magnetosphere. The magnetosphere is a complex, dynamic system with at least two independent coupling methods for energy input, driven and unloading. Linear models were built and tested on the Bargatze data set, consisting of over 70 days of geomagnetic indices and solar wind data ordered in 34 intervals of increasing geomagnetic activity. Linear filtering techniques employing single-and multiple-input, autoregressive models predicted values of the magnetic index AL from solar wind data. The impulse response curves of the AL-coupling function groups showed amplitude peaks …

Visualization Of Scalar Topology For Structural Enhancement, Chandrajit L. Bajaj, Daniel R. Schikore

Department of Computer Science Technical Reports

No abstract provided.

A Survey Of Mobile Transaction Models, Abdelsalam Helal, Santosh Balakrishnan, Margaret Dunham, Ramez Elmasri

Department of Computer Science Technical Reports

No abstract provided.

Scalable Scientific Software Libraries And Problem Solving Environments, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

On Neurobiological, Neuro-Fuzzy And Statistical Pattern Recognition Techniques, Anupam Joshi, Narendran Ramakrishnan, Elias N. Houstis, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

A Graph-Constructive Approach To Solving Systems Of Geomeric Constraints, Ioannis Fudos, Christoph M. Hoffmann

Department of Computer Science Technical Reports

No abstract provided.

Tau Leptonic Branching Ratios, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

A sample of 62249 τ-pair events is selected from data taken with the ALEPH detector in 1991, 1992 and 1993. The measurement of the branching fractions for τ decays into electrons and muons is presented with emphasis on the study of systematic effects from selection, particle identification and decay classification. The results obtained are: B e = 17.79±0.12(stat)±0.06(syst)(%) and Bμ = 17.31±0.11(stat)±0.05(syst)(%). Combined with the most recent ALEPH determination of the τ lifetime, these results provide a relative measurement of the leptonic couplings in the weak charged current for transverse W bosons: ${cal G}_{ώ}/{cal G}_{e}=1.0002pm 0.0051$ and ${cal G}_{∢u}/{cal G}_{u}=0.9943pm …