Digital Commons Network^™

The Apic Approach To High Performance Network Interface Design: Protected Dma And Other Techniques, Zubin D. Dittia, Guru M. Parulkar, Jerome R. Cox Jr.

All Computer Science and Engineering Research

We are building a very high performance 1.2 Gb/s ATM network interface chip called the APIC (ATM Port Interconnect Controller). In addition to borrowing userful ideas from a number of research and commercial prototypes, the APIC design embraces several innovative features, and integrates all of these pieces into a coherent whole. This paper describes some of the novel ideas that have been incorporated in the APIC design with a view to improving the bandwidth and latency seen by end-applications. Among the techniques described, Protected DMA and Protected I/O were designed to allow applications to queue data for transmission or reception …

Mobile Unity Coordination Constructs Applied To Packet Forwarding For Mobile Hosts, Peter J. Mccann, Gruia-Catalin Roman

All Computer Science and Engineering Research

With recent advances in wireless communication technology, mobile computing is an increasingly important area of research. A mobile system is one where independently executing components may migrate through some space during the course of the computation, and where the pattern of connectivity among the components changes as they move in and out of proximity. Mobile UNITY is a language and logic for specifying and reasoning about mobile systems, the components of which must operate in a highly decoupled way. In this paper it is argued that Mobile UNITY contributes to the modular development of system specifications because of the declarative …

Continuous Compilation For Software Development And Mobile Computing, Michael P. Plezbert

All Computer Science and Engineering Research

Software developers typically must choose between interpreted and compiled environments for their programming activities. However, the current trends toward mobile computing and platform independence suggest moving to a new continuous compilation paradigm that integrates the advantages of each environment. Movement in this direction can already be seen in the development of Sun Microsystems' Java environment. The resulting continuous compiler operates not as a prelude to, but rather in tandem with, program execution. In this thesis we present the results of experiments that compare the performance of the continuous compilation model with a more traditional model and show that a performance …

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.

A Usability Study Of End-User Construction Of Direct Manipulation User Interfaces, T Paul Mccartney

All Computer Science and Engineering Research

This paper describes an empirical study of end-users that tested the usability of The Programmers' Playground graphical environment. The Programmers' Playground is a software library and run-time system for constructing distributed multimedia applications. Playground's graphical environment enables end-users to create direct manipulation graphical user interfaces (GUIs) and to dynamically configure communication among distributed application components. In this study, 28 end-users with no prior experience in distributed computing or user interface construction were timed and evaluated on several tasks using our graphical environment. Tasks included the use of direct and indirect constraint relationships, visual configuration of distributed applications, and graphical user …

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 …

A Review Of Commercial And Research Cluster Management Software, Mark Baker, Geoffrey C. Fox, Hon W. Yau

Northeast Parallel Architecture Center

In the past decade there has been a dramatic shift from mainframe or ‘host-centric’ computing to a distributed ‘client-server’ approach. In the next few years this trend is likely to continue with further shifts towards ‘network-centric’ computing becoming apparent. All these trends were set in motion by the invention of the mass-reproducible microprocessor by Ted Hoff of Intel some twenty-odd years ago. The present generation of RISC microprocessors are now more than a match for mainframes in terms of cost and performance. The long-foreseen day when collections of RISC microprocessors assembled together as a parallel computer could outperform the vector …

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 …

The Distributed Array Descriptor For A Pcrc Hpf Compiler Version 2.0 Sccs-770d, Bryan Carpenter, James Cowie, Donald Leskiw, Xiaoming Li

Northeast Parallel Architecture Center

We describe a distributed array descriptor that can be used by a runtime supporting HPFlike compilers. This descriptor captures all five types of alignment and BLOCK and CYCLIC distribution as defined in HPF specification. In essence, this descriptor does not distinguish whole array and array sections. Prior to this version, we had versions 1.0, 1.1, and 1.2. This version is not only an update of previous versions, but more importantly it also directly reflects our current practice in an HPF compilation effort.

A Tale Of Two Applications On The Nii, Geoffrey C. Fox

Northeast Parallel Architecture Center

We describe the expected capability of the NII (as an evolution of the Internet) interns of five broad service areas---collaboration, multimedia information dissemination, commerce, metacomputing, and Webtop productivity. We illustrate the demands on these services and the technology implications by examination of two application areas---manufacture of complex systems, such as aircraft and crisis management, command and control.

Benchmarking The Computation And Communication Performance Of The Cm-5, Kivanc Dincer, Zeki Bozkus, Sanjay Ranka, Geoffrey C. Fox

Northeast Parallel Architecture Center

Thinking Machines' CM-5 machine is a distributed-memory, message-passing computer. In this paper we devise a performance benchmark for the base and vector units and the data communication networks of the CM-5 machine. We model the communication characteristics such as communication latency and bandwidths of point-to-point and global communication primitives. We show, on a simple Gaussian elimination code, that an accurate static performance estimation of parallel algorithms is possible by using those basic machine properties connected with computation, vectorization, communication, and synchronization. Furthermore, we describe the embedding of meshes or hypercubes on the CM-5 fat-tree topology and illustrate the performance results …

Efficient Algorithms For Array Redistribution, Rajeev Thakur, Alok Choudhary, J. Ramanujam

Electrical Engineering and Computer Science - All Scholarship

Dynamic redistribution of arrays is required very often in programs on distributed memory parallel computers. This paper presents efficient algorithms for redistribution between different cyclic(k) distributions, as defined in High Performance Fortran. We first propose special optimized algorithms for a cyclic(x) to cyclic(y) redistribution when x is a multiple of y, or y is a multiple of x. We then propose two algorithms, called the GCD method and the LCM method, for the general cyclic(x) to cyclic(y) redistribution when there is no particular relation between x and y. We have implemented these algorithms on the Intel Touchstone Delta, and find …

An Efficient Runge-Kutta (4,5) Pair, P. Bogacki, L. F. Shampine

Mathematics & Statistics Faculty Publications

A pair of explicit Runge-Kutta formulas of orders 4 and 5 is derived. It is significantly more efficient than the Fehlberg and Dormand-Prince pairs, and by standard measures it is of at least as high quality. There are two independent estimates of the local error. The local error of the interpolant is, to leading order, a problem-independent function of the local error at the end of the step.

A Family Of Parallel Runge-Kutta Pairs, P. Bogacki

Mathematics & Statistics Faculty Publications

Increasing availability of parallel computers has recently spurred a substantial amount of research concerned with designing explicit Runge-Kutta methods to be implemented on such computers. Here, we discuss a family of methods that require fewer processors than methods presently available do, still achieving a similar speed-up. In particular, (5,6) and (6,7) pairs are derived, that require a minimum number of function evaluations on two and three processors, respectively.

An Extended Two-Phase Method For Accessing Sections Of Out-Of-Core Arrays, Rajeev Thakur, Alok Choudhary

Electrical Engineering and Computer Science - All Scholarship

A number of applications on parallel computers deal with very large data sets that cannot fit in the main memory. In such applications, data must be stored in files on disks and fetched into memory during program execution. Parallel programs with large out-of-core arrays stored in files must read/write smaller sections of the arrays from/to files. In this paper, we describe a method for accessing sections of out-of-core arrays efficiently. Our method, the extended two phase method, uses collective I/O: Processors cooperate to combine several I/O requests into fewer larger granularity requests, reorder requests so that the file is accessed …

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 …

A Formal Preparation For Object-Oriented Query Optimisation, Catherine Higgins

Articles

This paper describes work that is in progress on a formalised preparation to object-oriented query optimisation. Such preparation is conducive to the development of optimisation strategies. As an example of a formal preparation, this paper presents a formalised object algebra, a suggested optimisation method and an implementation of an algebraic converter suitable for DAPLEX.

Embedded Particle Computation In Evolved Cellular Automata, Wim Hordijk, James P. Crutchfield, Melanie Mitchell

Computer Science Faculty Publications and Presentations

In our work we are studying how genetic algorithms (GAs) can evolve cellular automata (CAs) to perform computations that require global coordination. The evolving cellular automata" framework is an idealized means for studying how evolution (natural or computational) can create systems that perform emergent computation, in which the actions of simple components with local information and communication give rise to coordinated global information processing [3].

In previous work [4, 5], we analyzed the process by which a genetic algorithm designed CAs to perform particular tasks. In this paper we focus on how these CAs implement the emergent computational strategies for …

Parallel Newton-Krylov-Schwarz Solvers For The Full Potential Flow Equation, Jie Zhang

Computer Science Theses & Dissertations

Newton-Krylov-Schwarz methods are increasingly applied in Computational Fluid Dynamics (CFD). We develop a parallel analysis code based on this method for the full potential flow model. The full potential model consists of a single nonlinear second-order partial differential equation of mixed type (elliptic/hyperbolic), which we solve as a steady boundary-value problem.

We use a nine-point finite-difference stencil to discretize the equation. A Newtonlike linearization and correction method is used to solve the resulting set of nonlinear algebraic equations. To solve the inner linear equations, we employ a Krylov space method. Preconditioners are used to improve the convergence rate. In order …

Three-Dimensional Segmentation And Visualization Of Magnetic Resonance Imaging Data, William L. Bell Jr.

UNF Graduate Theses and Dissertations

In this thesis, I shall study and compare various methods for manipulating two- and three-dimensional image data produced with a nuclear magnetic resonance scanner. In particular, I will examine ways of focusing upon specific structures internal to the object under study (segmentation); and will explore means of rendering realistic images of these structures on a computer screen using depth-cueing, shading, and ray-casting techniques.
The 3DHEAD volumetric dataset used for this project was created with the Siemens Magnetom and was provided courtesy of Siemens Medical Systems, Inc., Iselin, NJ. This dataset consists of 109 slices of a human head, with each …

A Search Tool To Enhance The Selection And Utilisation Of Reusable Software Modules Within The Object-Oriented Paradigm, Robert H. Cross

Theses: Doctorates and Masters

The affinity for reuse within the object-oriented paradigm may enable high levels of productivity; however, gains will become realisable only if a systems developer has access to tools which aid in the selection of classes. A method for object-oriented analysis and design is detailed and its process is assisted by an object-oriented search tool based on reference and corporate library technology. The search tool contributes to the determination of suitable existing inheritable classes and an explanation of its construction and use is included. A practical demonstration of the method, using the search tool, is elaborated. The thesis demonstrates that text …

An Adaptive Fuzzy Logic Controller For Intelligent Networking And Control, Irshad Nainar

Theses: Doctorates and Masters

In this thesis, we present a fuzzy logic control scheme to regulate the flow of traffic approaching a set of intersections. An adaptive Fuzzy Logic Traffic Controller (FLTC) is used to adjust the green phase split of the north-south and east-west approaches of a set of traffic signals based on the actual traffic approaching the intersection. Each intersection is coordinated with its neighbouring intersections by adjusting the offset of the local intersection. The offset is adjusted by a local fuzzy logic controller loacted at each intersection. A new fuzzy control scheme, using a supervisory Fuzzy Logic Controller, is also proposed …

The Design And Implementation Of A Toolkit For The Creation Of Virtual Environments, Jesse Kinross-Smith

Theses : Honours

Virtual Reality is a field that is steadily increasing in popularity and interest. New developments in both hardware and software have empowered developers with new devices allowing faster and better quality interaction with virtual environments. However, the emphasis of research in virtual environments has been more concerned with development of new display and input devices, as opposed to the investigation of different methods of interaction that a three-dimensional environment offers. This project designs and implements a three-dimensional, interactive, virtual environment development system upon an existing three-dimensional rendering engine. The aim of the project is to allow users to generate virtual …

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.

An Investigation Into An Effective Method Of Automatically Analysing Oracle Applications To Count Function Points, J. L. Wong

Theses : Honours

Function Point Analysis (FPA) is a synthetic software estimation metric used for computing the size and complexity of applications. It was first introduced by Allan. J. Albrecht during the mid-seventies, as a result of a lengthy research based on applications that were developed using COBOL and PL/1 programming languages. The purpose of this research· is to investigate the possibility, and the most effective method, of automatically performing a Function Point Analysis on Oracle applications that consist of Oracle Forms and Oracle Reports. The research revealed a seemingly lack of other researches on this topic. As FPA was invented a few …

Web Intelligent Query - Disconnected Web Browsing Using Cooperative Techniques, Ramanathan Kavasseri, Todd Keating, Michael Wittman, Anupam Joshi, Sanjiva Weerawarana

Department of Computer Science Technical Reports

No abstract provided.

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.

Average Profile Of Generalized Digital Search Trees And The Generalized Lempel-Ziv Algorithm, Guy Louchard, Wojciech Szpankowski, Jing Tang

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.