Digital Commons Network^™

Pattern Matching With Mismatches: A Simple Randomized Algorithm And Its Analysis, Mikhail J. Atallah, Philippe Jacquet, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

A Data Structure For Dynamically Maintaining Rooted Trees, Greg N. Frederickson

Department of Computer Science Technical Reports

No abstract provided.

On The Separability Problem Of Real Functions And Its Significance In Solid Modeling, Christoph M. Hoffmann

Department of Computer Science Technical Reports

No abstract provided.

Piecewise Rational Approximations Of Real Algebraic Curves, Chanderjit L. Bajaj, Guoliang Xu

Department of Computer Science Technical Reports

No abstract provided.

Can Pac Learning Algorithms Tolerate Random Attribute Noise?, Sally A. Goldman, Robert H. Sloane

All Computer Science and Engineering Research

This paper studies the robustness of pac learning algorithms when the instances space is {0,1}n, and the examples are corrupted by purely random noise affecting only the instances (and not the labels). In the past, conflicting results on this subject have been obtained -- the "best agreement" rule can only tolerate small amounts of noise, yet in some cases large amounts of noise can be tolerated. We show that the truth lies somewhere in between these two alternatives. For uniform attribute noise, in which each attribute is flipped independently at random with the same probability, we present an algorithm that …

Ccis Networking - July 1992, Nova University

CCIS Networking / SCIS Networking magazines

No abstract provided.

Neural Modeling And Control Of A Distillation Column, James Edward Steck, K. Krishnamurthy, Bruce M. Mcmillin, Gary G. Leininger

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Control of a nine-stage three-component distillation column is considered. The control objective is achieved using a neural estimator and a neural controller. The neural estimator is trained to represent the chemical process accurately, and the neural controller is trained to give an input to the chemical process which will yield the desired output. Training of both the neural networks is accomplished using a recursive least squares training algorithm implemented on an Intel iPSC/2 multicomputer (hypercube). Simulated results are presented for a numerical example.

Fault Tolerance In Concurrent Systems Through Formal Methods, H. Lutfiyya, B. M. Mcmillin

Computer Science Technical Reports

An important aspect which is often overlooked in the software design cycle is the question of assurance. Many methodologies in the past have attempted to provide assurance efficiently, but have never been sucessful at eliminating explicit time and space redundancy. One approach is the Application-Oriented Fault Tolerance Paradigm, which provides assurance by examining the behavior and propenies of the application and deriving executable assertions for the detection of faults. Previous work has demonstrated the feasibility of the application-oriented fault tolerance paradigm for various applications. However, the executable assertions were guided by the natural constraints of the problem. This work focuses …

Visual Graphic Knowledge Management Methodology, Jih-Shih Hsu

Computer Science Theses & Dissertations

As computer technology evolves, graphic workstations are becoming more popular. They support more friendly user interfaces than do conventional terminals. The better user interfaces require more effort to develop. Therefore, many user interface (UI) design systems have been developed to facilitate the creation of modern user interfaces, but not very successfully. Many of them either provide limited features or are difficult to use. Besides, these UI design systems are actually like black boxes to their users because the underlying technology is opaque; their users cannot learn how to utilize the underlying window systems through user interface design sessions. In a …

Multigrid Algorithms For Massively Parallel Machines, Satyanarayan Gupta

Computer Science Theses & Dissertations

Numerical solutions of partial differential equations (pde's) are required in many physical problems arising in areas such as computational fluid dynamics, atmospheric sciences, electromagnetics etc. One of the most popular methods of solving pde's is the use of the multigrid algorithm. However, the implementation of the multigrid algorithm on massively parallel machines is not very efficient because of (i) low processor utilization and (ii) high communication overheads. These problems need to be addressed to make better use of massively parallel machines for solving pde's using the multigrid algorithm.

In this dissertation, we present three parallel multigrid algorithms which …

On Global Transaction Scheduling Criteria In Multidatabase Systems, Aidong Zhang, Ahmed K. Elmagarmid

Department of Computer Science Technical Reports

No abstract provided.

On Structure Features Of Global Transactions In Multidatabase Systems, Aidong Zhang, Jin Jing

Department of Computer Science Technical Reports

No abstract provided.

Text-Independent Automatic Speaker Identification Using Partitioned Neural Networks, Laszlo Rudasi

Electrical & Computer Engineering Theses & Dissertations

This dissertation introduces a binary partitioned approach to statistical pattern classification which is applied to talker identification using neural networks. In recent years artificial neural networks have been shown to work exceptionally well for small but difficult pattern classification tasks. However, their application to large tasks (i.e., having more than ten to 20 categories) is limited by a dramatic increase in required training time. The time required to train a single network to perform N-way classification is nearly proportional to the exponential of N. In contrast, the binary partitioned approach requires training times on the order of N². …

High Performance Issues On Parallel Architectures, Peter J. Looges

Computer Science Theses & Dissertations

In an effort to reduce communication latency in mesh-type architectures, these architectures have been augmented by various types of global and reconfigurable bus structures. The static bus structures provide excellent performance in many areas of computation especially structured numerical computations, but they lack the flexibility required of many large numerical and non-numerical applications. Reconfigurable bus systems have the dynamic adaptability to handle a much wider range of applications. While reconfigurable meshes can often yield constant time results for many problems, the cost of this performance is paid in the number of processors required. While in actuality the majority of these …

Parallel Computer Needs At Dartmouth College, David Kotz, Fillia Makedon, Matt Bishop, Scot Drysdale, Don Johnson, Takis Metaxas

Computer Science Technical Reports

To determine the need for a parallel computer on campus, a committee of the Graduate Program in Computer Science surveyed selected Dartmouth College faculty and students in December, 1991, and January, 1992. We hope that the information in this report can be used by many groups on campus, including the Computer Science graduate program and DAGS summer institute, Kiewit's NH Supercomputer Initiative, and by numerous researchers hoping to collaborate with people in other disciplines.

We found significant interest in parallel supercomputing on campus. An on-campus parallel supercomputing facility would not only support numerous courses and research projects, but would provide …

Netsim: A Network Performance Simulator, Lewis Barnett Iii

Department of Math & Statistics Technical Report Series

The performance of computer communication networks is often given only cursory treatment in undergraduate Networking or Computer Communication courses. A simulation package for the investigation of many aspects of Local Area Network (LAN) performance is introduced. Its use as a tool for allowing undergraduate Networking students to investigate the performance of a popular networking system is discussed.

Linear Assignment Problem Revisited: Average (1 + 1/E)-Out Degree Bipartite Graph Has A Perfect Match, Michael Karoński, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

Nurbs Approximation Of Surface/Surface Intersection Curves, Chandrajit L. Bajaj, Gualiang Xu

Department of Computer Science Technical Reports

No abstract provided.

Exact Arithmetic Solid Modeling (Ph.D. Thesis), Juixun, Yu

Department of Computer Science Technical Reports

No abstract provided.

Parallel Iterative Methods, N. P. Christochoides, Elias N. Houstis, S. B. Kim, M. K. Samartzis, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

Parallel Monte Carlo Trials, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

The best results of Monte Carlo methods are generally obtained by performing the same computation many times with different random numbers. We develop a generic algorithm for parallel execution of Monte Carlo trials on a multicomputer. The generic algorithm has been adapted for simulated annealing and primality testing by simple substitutions of data types and procedures. The performance of the parallel algorithms was measured on a Computing Surface.

Designing Efficient Maximum-Likelihood Soft-Decision Decoding Algorithms For Linear Block Codes Using Algorithm A*, Yunghsiang S. Han, Carlos R.P. Hartmann

Electrical Engineering and Computer Science - Technical Reports

In this report we present a class of efficient maximum-likelihood soft-decision decoding algorithms for linear block codes. The approach used here is to convert the decoding problem into a search problem through a graph which is a trellis for an equivalent code of the transmitted code. Algorithm A*, which uses a priority-first search strategy, is employed to search through this graph. This search is guided by an evaluation function f defined to take advantage of the information provided by the received vector and the inherent properties of the transmitted code. This function f is used to drastically reduce the search …

Primality Testing, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

This tutorial describes the Miller-Rabin method for testing the primality of large integers. The method is illustrated by a Pascal algorithm. The performance of the algorithm was measured on a Computing Surface.

Simulated Annealing, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

This tutorial describes simulated annealing, an optimization method based on the principles of statistical mechanics. Simulated annealing finds near-optimal solutions to optimization problems that cannot be solved exactly because they are NP-complete. The method is illustrated by a Pascal algorithm for the traveling salesperson problem. The performance of the algorithm was measured on a Computing Surface.

The 3-Tier Structured Access Protocol To Control Unfairness In Dqdb Mans, Lakshmana N. Kumar, Andreas D. Bovopoulos

All Computer Science and Engineering Research

This paper addresses the unfairness problem appearing in 802.6-based DQDB MANs. Traffic load demand is characterized as low (below 0.4 of the channel capacity), normal (from 0.4 to 0.9 of the channel capacity) or heavy (greater than 0.9 of the channel capacity). At low loads the 802.6 protocol is acceptably fair. At normal loads, however, the protocol performance is markedly unfair. The unfairness is related to the latency in transporting a request. At heavy loads the unfairness is both latency-related and flooding-related. In this paper, both types of unfairness are carefully analyzed. As a control measure, a 3-Tier Structured Access …

Algorithms For Structural Schema Integration, James Geller, Ashish Mehra, Yehoshua Perl, Erich Neuhold, Amit P. Sheth

Kno.e.sis Publications

Current view and schema integration methodologies are driven by semantic considerations, and allow integration of objects only if that is valid from semantic and structural viewpoints. We had introduced a new integration technique called structural integration. It permits integration of objects that have structural similarities, even if they differ semantically. This technique uses the object-oriented Dual Model which separates the representation of structure and semantics.

In this paper we introduce algorithms for structural integration. We apply these algorithms to integrate two views of a large university database schema which had significant structural similarities but differed semantically.

Sequential And Parallel Discrete Event Simulation On Computer Communication Networks, Tao Zhou

Masters Theses

This thesis presents the discrete event simulation technique on the network design, focusing on the methodology, modeling and implementation. The developed technique is suitable for the analysis of any store-and-forward computer communication networks with any level of complexity. The proposed generic simulation model can be used to test the architectures and protocols of existing networks and networks being designed. In implementation of the sequential discrete event simulation, an object-oriented programming strategy is applied to the network simulation using the C++ language. The parallel discrete event simulation is introduced to solve the problem of long time execution of the sequential simulation …

Design Of A Laboratory Computer Interface, Douglas L. Durand

Theses and Dissertations

An interface for the LSI-11 computer was designed and implemented so that the computer supports data acquisition, data reduction, and equipment control. The design includes both hardware and software and addresses both parallel and serial input/output (I/0). The serial interface's hardware is simply a Serial Line Unit card. This card plugs into the LSI-11 bus and provides the signals necessary to interface EIA RS-232 compatible devices. A software utility was developed to allow communication with the serial device and to allow exchange of data files. Routines were written to allow serial I/O through a FORTRAN program. The interface's parallel hardware …

Graphical Image Persistence And Code Generation For Object Oriented Databases, Subrata Chatterjee

Theses

Attached is the detailed description of the design and implementation of graphical image persistence and code generation for object oriented databases. Graphical image persistent is incorporated into a graphics editor called OODINI. OODINI creates and manipulates graphical schemas for object-oriented databases. This graphical image on secondary storage is then translated into an abstract, generic code for dual model databases. This abstract code, DAL can then be converted into different dual model database languages. We provide an example by generating code for the VODAK Data Modeling language. It is also possible to generate a different abstract language code, OODAL from a …

Transformations And Analysis Of Parallel Real Time Programs, Chandima J. Gunasekara

Theses

The problem of schedulability analysis of a set of real time programs form a NP complete problem. The exponential complexity of analysis is a direct result of the complexity in the real time programs, as a combinatorial explosion takes place when trying to determine access patterns of shared resources. Thus, to transform the original programs to a less complex form, while preserving its timing characteristics, is the only viable solution. By using such transformations to reduce the complexity of real time programs, it is possible to schedulability analyze programs at compile time efficiently, without adding an unnecessary overhead to the …