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Full-Text Articles in Physical Sciences and Mathematics

Production And Decay Of D1 (2420)0 And D2* (2460)0, Avery, P.; Et Al., M. Thulasidas Jun 1994

Production And Decay Of D1 (2420)0 And D2* (2460)0, Avery, P.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


Searching For Plans Using A Hierarchy Of Learned Macros And Selective Reuse, Douglas E. Dyer Jun 1994

Searching For Plans Using A Hierarchy Of Learned Macros And Selective Reuse, Douglas E. Dyer

Theses and Dissertations

This research presents a new approach to improving the performance of a macro planner: selective reuse. In macro planning, reuse can result in poorer performance than when planning with only primitive operators, a phenomenon that has been called the utility problem. The utility problem arises because the benefits of reuse are outweighed by the cost of retrieving a macro to reuse and the cost of searching through the larger search space caused by considering reuse candidates. Selective reuse contains the expansion of the search space by limiting the number of reuse candidates considered and limits the search required by considering …


Floorplanning For Mixed Block And Cell Designs, Arun G. Shanbhag Jun 1994

Floorplanning For Mixed Block And Cell Designs, Arun G. Shanbhag

Masters Theses

Floorplanning is one of the important phases of the VLSI Physical Design cycle. The quality of a floorplan is usually not evident until the routing phase. A bad floorplan can lead to an unroutable design requiring another iteration of the floorplanning phase. Use of over-the-cell routing has led to zero routing footprints. Any further reduction in area of the layout is possible only by reducing the white space or the vacant space from the floorplan, that is by improving the floorplan of the layout.

Currently, the Mixed Block and Cell (MBC) design style is gaining popularity. This evolving design style …


Teaching Parallel Computing To Freshmen, Donald Johnson, David Kotz, Fillia Makedon Jun 1994

Teaching Parallel Computing To Freshmen, Donald Johnson, David Kotz, Fillia Makedon

Dartmouth Scholarship

Parallelism is the future of computing and computer science and should therefore be at the heart of the CS curriculum. Instead of continuing along the evolutionary path by introducing parallel computation “top down” (first in special junior-senior level courses), we are taking a radical approach and introducing parallelism at the earliest possible stages of instruction. Specifically, we are developing a completely new freshman-level course on data structures that integrates parallel computation naturally, and retains the emphasis on laboratory instruction. This will help to steer our curriculum as expeditiously as possible toward parallel computing.

Our approach is novel in three distinct …


Parallel Exact Enumeration Of Self-Avoiding Walk On Cubic Lattices And Its Applications To Protein Folding Studies, Anek Vorapanya May 1994

Parallel Exact Enumeration Of Self-Avoiding Walk On Cubic Lattices And Its Applications To Protein Folding Studies, Anek Vorapanya

Theses

Exact enumeration of self-avoiding walk on many lattices have been studied extensively recently. Even a short chain polymer (about 30 monomers) represented as a chain of cubic lattice sites requires a considerable amount of computer time to exhaustively search for all unique conformations. However, self-avoiding walk process can be modified such that it exhibits a high degree of independence among subprocesses. Parallel implementation of such subprocesses can reduce a great amount of enumeration time. Parallel enumeration makes longer chain enumeration possible.

Enumerating only unique conformations requires that all rotation and mirror conformations be removed. An algorithm to avoid generating such …


Extracting Parallelism At Compile-Time Through Dependence Analysis & Cloning Techniques In An Object-Based Paradigm, Binoy Ravindran May 1994

Extracting Parallelism At Compile-Time Through Dependence Analysis & Cloning Techniques In An Object-Based Paradigm, Binoy Ravindran

Theses

The construct of Abstract Data Type (ADT) modules and Abstract Data Object (ADO) modules supported by most object-based languages are a great source for developing reusable code. To improve the run time performance of such object-based programs, we consider the asynchronous remote procedure call (ARPC) model of parallel execution, in which concurrency is achieved by having the caller and the callee (which are module instances) running on different processors. Frequently, an ADT module is needed simultaneously by other modules, thus causing contention. To resolve this, we clone the module instance in demand and distribute the copies across different processors, so …


Quickadvise - The Search For A More Efficient Method Of Advising, Gregory G. Pengiel '94 May 1994

Quickadvise - The Search For A More Efficient Method Of Advising, Gregory G. Pengiel '94

Honors Projects

In order to choose courses both efficiently and properly, a student and advisor must look at which courses have been taken, and also which ones are necessary. They must then determine whether or not the student is qualified to take the necessary courses. Unfortunately, there is no easy way to record and maintain this work so that it may be used throughout the college career.
Hence, even though the student and advisor recently determined which classes were headed, they must once again look up all relevant information and determine which courses are best. This is exactly the type of problem …


Fast Greedy Triangulation Algorithms, Matthew T. Dickerson, Robert L. Scot Drysdale, Scott A. Mcelfresh, Emo Welzl May 1994

Fast Greedy Triangulation Algorithms, Matthew T. Dickerson, Robert L. Scot Drysdale, Scott A. Mcelfresh, Emo Welzl

Computer Science Technical Reports

The greedy triangulation of a set $S$ of $n$ points in the plane is the triangulation obtained by starting with the empty set and at each step adding the shortest compatible edge between two of the points, where a compatible edge is defined to be an edge that crosses none of the previously added edges. In this paper we present a simple, practical algorithm that computes the greedy triangulation in expected time $O(n \log n)$ and space $O(n)$ for points uniformly distributed over any convex shape. A variant of this algorithm should be fast for some other distributions. As part …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 5, May 1994, College Of Engineering And Computer Science, Wright State University May 1994

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 5, May 1994, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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


Image Processing Techniques And Implementations In Software For Use With A Ccd Camera, Clarence Franklin Jr. May 1994

Image Processing Techniques And Implementations In Software For Use With A Ccd Camera, Clarence Franklin Jr.

Opportunities for Undergraduate Research Experience Program (OURE)

The concept of image processing is used whenever there is a reference to digital images. By random and natural errors introduced into the image during collection and transmission, the images are distorted. Image processing techniques are used to eliminate these error before viewing of the images. For this experiment, the images provided by the ST-6 CCD Camera System will be used in the development and implementation of image processing techniques into a software package.


A Software Platform For Integrating Symbolic Computation With A Pde Solving Environment, Sanjiva Weerawarana, Elias N. Houstis, John R. Rice May 1994

A Software Platform For Integrating Symbolic Computation With A Pde Solving Environment, Sanjiva Weerawarana, Elias N. Houstis, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.


The Roles Of Models, Software Tools, And Applications In High Performance Computing, Leah H. Jamieson, Susanne E. Hambrusch, Ashfaq A. Khokhar, Edward J. Delp May 1994

The Roles Of Models, Software Tools, And Applications In High Performance Computing, Leah H. Jamieson, Susanne E. Hambrusch, Ashfaq A. Khokhar, Edward J. Delp

Department of Computer Science Technical Reports

No abstract provided.


Building Information Systems For Mobile Environments, Evaggelia Pitoura, Bharat Bhargava May 1994

Building Information Systems For Mobile Environments, Evaggelia Pitoura, Bharat Bhargava

Department of Computer Science Technical Reports

No abstract provided.


Communication Operations On Coarse-Grained Mesh Architectures, Susanne E. Hambrusch, Farooq Hameed, Ashfaq A. Khokhar May 1994

Communication Operations On Coarse-Grained Mesh Architectures, Susanne E. Hambrusch, Farooq Hameed, Ashfaq A. Khokhar

Department of Computer Science Technical Reports

No abstract provided.


Polynomial Surface Patch Representations, Chandrajit L. Bajaj May 1994

Polynomial Surface Patch Representations, Chandrajit L. Bajaj

Department of Computer Science Technical Reports

No abstract provided.


The Analysis Of Iterative Elliptic Pde Solvers Based On The Cubic Hermite Collocation Discretization, Yu-Ling Lai, Apostolos Hadjidimos, Elias N. Houstis, John R. Rice May 1994

The Analysis Of Iterative Elliptic Pde Solvers Based On The Cubic Hermite Collocation Discretization, Yu-Ling Lai, Apostolos Hadjidimos, Elias N. Houstis, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.


An Open Structure For Pde Solving Systems, Elias N. Houstis, John R. Rice, Sanjiva Weerawarana May 1994

An Open Structure For Pde Solving Systems, Elias N. Houstis, John R. Rice, Sanjiva Weerawarana

Department of Computer Science Technical Reports

No abstract provided.


Constraint Objects, Divesh Srivastava, Raghu Ramakrishnan, Peter Revesz May 1994

Constraint Objects, Divesh Srivastava, Raghu Ramakrishnan, Peter Revesz

CSE Conference and Workshop Papers

We describe the Constraint Object Data Model (CODM), which enhances an object-based data model with existential constraints to naturally represent partially specified information. We present the Constraint Object Query Language (COQL), a declarative, rule-based query language that can be used to infer relationships about and monotonically refine information represented in the CODM. COQL has a model-theoretic and an equivalent fixed-point semantics, based on the notions of constraint entailment and "proofs in all possible worlds." We also provide a novel polynomial-time algorithm for quantifier elimination for set-order constraints, a restricted class of set constraints that uses membership of subset-equal.


Designing A New Programming Methodology For Optimizing Array Accesses In Complex Scientific Problems, Larry Coffin May 1994

Designing A New Programming Methodology For Optimizing Array Accesses In Complex Scientific Problems, Larry Coffin

Opportunities for Undergraduate Research Experience Program (OURE)

Many problems of interest to scientists and engineers, such as fluid flow and stress analysis, require the solution of complex PDEs. Often the solution requires discretizing the physical domain into a mesh or grid then stepping from a given initial state towards some final state using small incremental time steps. Grid sizes can reach several thousand to hundreds of thousands of elements and the number of time steps required to solve the problem can vary from several thousand to tens of thousands or more. Traditional programming techniques are unable to take advantage of the non-random grid access patterns and generally …


Managing Memory For Real-Time Queries, Hwee Hwa Pang, Michael J. Carey, Miron Livny May 1994

Managing Memory For Real-Time Queries, Hwee Hwa Pang, Michael J. Carey, Miron Livny

Research Collection School Of Computing and Information Systems

The demanding performance objectives that real-time database systems (RTDBS) face necessitate the use of priority resource scheduling. This paper introduces a Priority Memory Management (PMM) algorithm that is designed to schedule queries in RTDBS. PMM attempts to minimize the number of missed deadlines by adapting both its multiprogramming level and its memory allocation strategy to the characteristics of the offered workload. A series of simulation experiments confirms that PMM's admission control and memory allocation mechanisms are very effective for real-time query scheduling.


Subgrouped Real Time Recurrent Learning Neural Networks, Jeffrey S. Dean May 1994

Subgrouped Real Time Recurrent Learning Neural Networks, Jeffrey S. Dean

Theses and Dissertations

A subgrouped Real Time Recurrent Learning (RTRL) network was evaluated. The one layer net successfully learns the XOR problem, and can be trained to perform time dependent functions. The net was tested as a predictor on the behavior of a signal, based on past behavior. While the net was not able to predict the signal's future behavior, it tracked the signal closely. The net was also tested as a classifier for time varying phenomena; for the differentiation of five classes of vehicle images based on features extracted from the visual information. The net achieved a 99.2% accuracy in recognizing the …


Course Scheduling Software: Reference Manual, Saadatu Gobir May 1994

Course Scheduling Software: Reference Manual, Saadatu Gobir

Honors Projects

Welcome to version 1.0 of the Course Scheduling software. Course Scheduling is designed to meet needs of anyone who is tying to create a course schedule. This software is a product that compiles, links, and runs in C++; although it has C extension. It has been specifically designed to work In C++ exclusively. I had mixed a little of C++ functions with C structure programming to complete this package and make it more efficient. It is versatile, quick, and efficient. This instruction manual is brief, due to fact that the software is well documented. It only covers the basic functions …


Multirate Time-Frequency Distributions, John R. O'Hair May 1994

Multirate Time-Frequency Distributions, John R. O'Hair

Theses and Dissertations

Multirate systems, which find application in the design and analysis of filter banks, are demonstrated to also be useful as a computational paradigm. It is shown that any problem which can be expressed a set of vector-vector, matrix-vector or matrix-matrix operations can be recast using multirate. This means all of numerical linear algebra can be recast using multirate as the underlying computational paradigm. As a non-trivial example, the multirate computational paradigm is applied to the problem of Generalized Discrete Time- Frequency Distributions GDTFD to create a new family of fast algorithms. The first of this new class of distributions is …


A User-Level Process Package For Concurrent Computing, Ravi Konuru, Steve Otto, Jonathan Walpole, Robert Prouty, Jeremy Casas May 1994

A User-Level Process Package For Concurrent Computing, Ravi Konuru, Steve Otto, Jonathan Walpole, Robert Prouty, Jeremy Casas

Computer Science Faculty Publications and Presentations

A lightweight user-level process(ULP) package for parallel computing is described. Each ULP has its own register context, stack, data and heap space and communication with other ULPs is performed using locally synchronous, location transparent, message passing primitives. The aim of the package is to provide support for lightweight over-decomposition, optimized local communication and transparent dynamic migration. The package supports a subset of the Parallel Virtual Machine(PVM) interface[Sun90).


Creation And Simulation Of A Model For A Discrete Time Buffer System With Interrupted Poisson Arrivals And Uncorrelated Server Interruptions, Susanne Naegele-Jackson May 1994

Creation And Simulation Of A Model For A Discrete Time Buffer System With Interrupted Poisson Arrivals And Uncorrelated Server Interruptions, Susanne Naegele-Jackson

Masters Theses & Specialist Projects

A mathematical model for a discrete-time buffer system with both arrival and server interruptions is developed. In this model fixed-size packets arrive at the buffer according to a Poisson distribution and are stored there until they can be transmitted over the output channel. Service times are constant and the buffer is assumed to be of infinite size. Both arrival stream as well as the service of the packets are subjected to random interruptions described by Bernoulli processes, where the interruption process of the Poisson input stream is uncorrelated to the interruptions of the output line. Expressions are derived for the …


The Expected Lifetime Of “Single-Address-Space” Operating Systems, David Kotz, Preston Crow May 1994

The Expected Lifetime Of “Single-Address-Space” Operating Systems, David Kotz, Preston Crow

Dartmouth Scholarship

Trends toward shared-memory programming paradigms, large (64-bit) address spaces, and memory-mapped files have led some to propose the use of a single virtual-address space, shared by all processes and processors. Typical proposals require the single address space to contain all process-private data, shared data, and stored files. To simplify management of an address space where stale pointers make it difficult to re-use addresses, some have claimed that a 64-bit address space is sufficiently large that there is no need to ever re-use addresses. Unfortunately, there has been no data to either support or refute these claims, or to aid in …


The Myriad Federated Database Prototype, San-Yih Hwang, Ee Peng Lim, H. R. Yang, S. Musukula, K. Mediratta, M. Ganesh, D. Clements, J. Stenoien, Jaideep Srivastava May 1994

The Myriad Federated Database Prototype, San-Yih Hwang, Ee Peng Lim, H. R. Yang, S. Musukula, K. Mediratta, M. Ganesh, D. Clements, J. Stenoien, Jaideep Srivastava

Research Collection School Of Computing and Information Systems

Myriad is a federated database system (FDBS) prototype being developed at the University of Minnesota. The main objective behind this prototyping effort is to provide "enterprise-wide" information by integrating independently developed databases while preserving the local autonomy of the component DBMSs and applications. In Myriad, multiple federations can be formed. A federation consists of an integrated database whose schema is represented as a set of integrated relations derived from the export relations provided by the component DBMSS. SQL, mainly due to its simplicity and popularity among database users and vendors, has been adopted to express global queries as well as …


Benefits Of Using Team Choice For Windows As A Multi-Criteria Decision Making Group Decision Support System, Eddie Goggans Apr 1994

Benefits Of Using Team Choice For Windows As A Multi-Criteria Decision Making Group Decision Support System, Eddie Goggans

Mahurin Honors College Capstone Experience/Thesis Projects

Various experiments have been conducted over the past ten years using several different types of group decision support systems (GDSSs). Many previous GDSS designs have had success in these experiments with brainstorming but have been limited in providing judgment and choice support. TeamChoice for Windows is a multi-criteria decision making GDSS that is currently under development in an effort to overcome the limitations of previous systems and to significantly advance the capabilities of GDSSs. This paper discusses some of the general aspects of GDSSs, existing limitations, and explains the developments and use of TeamChoice for Windows as a multi-criteria decision …


Knowledge-Based Nonuniform Crossover, Harpal Maini, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Apr 1994

Knowledge-Based Nonuniform Crossover, Harpal Maini, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

We present a new "knowledge-based non-uniform crossover" (KNUX) operator for genetic algorithms (GA's) that generalizes uniform crossover. We extend this to "Dynamic KNUX" (DKNUX), which constantly updates the knowledge extracted so far from the environment's feedback on previously generated chromosomes. KNUX can improve on good solutions previously obtained by using other algorithms. The modifications made by KNUX are orthogonal to other changes in parameters of GA's, and can be pursued together with any other proposed improvements. Whereas most genetic search methods focus on improving the move-selection procedures, after having chosen a fixed move-generation mechanism, KNUX and DKNUX make the move-generation …


Classification Characteristics Of Som And Art2, J. J. Aleshunas, Daniel C. St. Clair, William E. Bond Apr 1994

Classification Characteristics Of Som And Art2, J. J. Aleshunas, Daniel C. St. Clair, William E. Bond

Mathematics and Statistics Faculty Research & Creative Works

Artificial neural network algorithms were originally designed to model human neural activities. They attempt to recreate the processes involved in such activities as learning, short term memory, and long-term memory. Two widely used unsupervised artificial neural network algorithms are the Self-Organizing Map (SOM) and Adaptive Resonance Theory (ART2). Each was designed to simulate a particular biological neural activity. Both can be used as unsupervised data classifiers. This paper compares performance characteristics of two unsupervised artificial neural network architectures; the SOM and the ART2 networks. The primary factors analyzed were classification accuracy, sensitivity to data noise, and sensitivity of the algorithm …