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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, March 1991, 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.

Dna Mapping Algorithms: Topological Mapping, Kenneth Moorman, Paul Poulosky, Will Gillett

All Computer Science and Engineering Research

There are several basic approaches that can be used in attempting to produce high-resolution DNA restriction maps. A standard approach is the match/merge approach in which first the topology of the map units being mapped together is suppressed and lists of potential matches between fragments are generated, and second the topology is introduced to eliminate matchlists which are inconsistent with the topology. This technical report documents a different approach to DNA mapping, known as topological mapping. In topological mapping the precedence of the two criteria are reversed, i.e., the topology of the two map units is used as the primary …

The Boundary Element Method Applied To The Two Dimensional Stefan Moving Boundary Problem, Donald C. Vosika

Theses and Dissertations

This thesis considers problems for which the boundary is not known before the problem is solved and must be determined as part of the solution. We consider a time dependent problem which results in a moving boundary. We look at the heat conduction/diffusion equation in one and two spatial dimensions. We use Green's Theorem to yield a Volterra boundary integral equation which involves an unknown function on the moving boundary. We use the boundary element method to obtain a solution. Graphical results for the two dimensional problem are presented.

Transfer Of 4gl Application From Ingres To Oracle, Adnan Altunisik

Theses and Dissertations

This paper documents the transfer of 4GL applications from INGRES to ORACLE. As a result of a fast and conceptual change in computer languages, 4GLs were developed and evolved. These are programming support tools whose goal is, basically, to make the programs more efficient by reducing the number of instructions. Both ORACLE and INGRES database systems use 4GLs to develop applications. Their 4GL environments and their facilities for application development are investigated and explained in depth in this effort. The TWX application, which was originally implemented in INGRES by using its 4GL, is designed and reimplemented in ORACLE. This is …

An Automated Red Player For The Theater Warfare Exercise, Karl W. Kabanek

Theses and Dissertations

The Theater Warfare Exercise (TWX) is a two-sided, theater-level, decision-making exercise created, maintained and used by the personnel at the Air Force Wargaming Center. It is used to allow military officers to practice the decision-making process needed for the wartime employment of air power. An automated player was designed and a prototype implemented for the red (enemy) player using an expert system shell. The automated red player uses the TWX database that contains the data on the different units used in exercise. From the data the automated red player builds mission packages for the various types of missions required in …

Optimal Iterative Task Scheduling For Parallel Simulations, Joann M. Sartor

Theses and Dissertations

The ultimate purpose of this research is to reduce the time needed for execution of parallel computer simulations. In particular, the impact of task assignment strategies is determined for parallel VHDL circuit simulations. The classical scheduling problem, which assigns n precedence-constrained tasks to m processors is NP-complete in all but the simplest cases. The problem of assigning simulation tasks is further complicated by the iterative nature of computer simulations: each task is required to execute multiple times as the simulation executes. This investigation develops a polynomial-time algorithm (the level strategy) which provides optimal assignment for iterative systems with specific constraints. …

A Computer Simulation Of Braitenberg Vehicles, Eric B. Werkowitz

Theses and Dissertations

In his treatise, Vehicles: Experiments in Synthetic Psychology, Valentino Braitenberg used simple, autonomous vehicle designs to illustrate the principles behind animal nervous system organization and operation. The goal of this effort was to produce a computer program to allow a researcher to experiment with these concepts and to analyze their performance using methods employed by experimental psychologists. The resulting program allows the user to design vehicles that respond to changes in their environments and that have the ability to adapt their behavior, using a learning algorithm developed by Teuvo Kohonen. The vehicle designer is free to select sensor attributes, …

Eliminating Extraneous Solutions In Curve And Surface Operations, Christoph M. Hoffmann, Pamela J. Vermeer

Department of Computer Science Technical Reports

No abstract provided.

Multisearch Techniques: Parallel Data Structures On Mesh-Connected Computers, Mikhail J. Atallah, Frank Dehne, Russ Miller, Andrew Rau-Chaplin, Jyh-Jong Tsay

Department of Computer Science Technical Reports

No abstract provided.

A Robust Intersection Algorithm Based On Delaunay Triangulation, Kokichi Sugihara

Department of Computer Science Technical Reports

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, February 1991, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

Performance Analysis Of The Ethernet Under Conditions Of Bursty Traffic, Tony Y. Mazraani, Gurudatta M. Parulkar

All Computer Science and Engineering Research

In this paper we present a simulation study of the Ethernet performance under conditions of bursty traffic. This study is motivated by two observations: Ethernet will continue to be a widely used Local Area Network (LAN), especially as an access LAN for future high speed internet (or Broadband ISDN); and future high speed applications can best be modeled as bursty sources. Bursty traffic in this study is specified using three parameters: peak bandwidth, average bandwidth, and burst factor. The simulation study shows that the inherent behavior of the Ethernet does not change with bursty traffic. That is, as long as …

Performance Evaluation Of A Traffic Control Mechanism For Atm Networks, Andreas D. Bovopoulos

All Computer Science and Engineering Research

Future ATM networks will be required to support a plethora of services, transaction types and cell sequence behaviors with performance guarantees. Before this goal can be realized, however, some basically problems related to bandwidth allocation and traffic control in the ATM layer must be resolve. Such problems will in all likelihood defy solution as long as they studied in isolation without a unifying traffic characterization and traffic control framework. This work presented in this paper is part of an ongoing effort directed at the development of an integrated traffic characterization and control infrastructure for ATM networks. In this paper a …

Saam: The Strategic Asset Allocation Model, Judy Lewis, Todd Gamble, John Tai

All Computer Science and Engineering Research

Asset Allocation has become a dominant factor for investment strategies in recent years. It has found that by holding a strategically diversified portfolio, a high total return on investments can be maintained while, at the same time, reducing portfolio volatility. With recent federal regulations mandating pension investment responsibilities, appropriate asset allocation has become more important than ever. SAAM is a software package specifically designed to be used as a tool to aid the investment professional in determining pension portfolio allocations. SAAM uses the expect system shell CLIPS, has a user-friendly interface, displays output graphically, and runs within the confines of …

A Practical Hierarchial Model Of Parallel Computation: The Model, Todd Heywood, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

We introduce a model of parallel computation that retains the ideal properties of the PRAM by using it as a sub-model, while simultaneously being more reflective of realistic parallel architectures by accounting for and providing abstract control over communication and synchronization costs. The Hierarchical PRAM (H-PRAM) model controls conceptual complexity in the face of asynchrony in two ways. First, by providing the simplifying assumption of synchronization to the design of algorithms, but allowing the algorithms to work asynchronously with each other; and organizing this "control asynchrony" via an implicit hierarchy relation. Second, by allowing the restriction of "communication asynchrony" in …

Concurrency Control, Version Management And Transactions In Advanced Database Systems, Jonathan Walpole, Muntuck Yap

Computer Science Faculty Publications and Presentations

This document constitutes the final deliverable for the research project titled “An Investigation of Selected Issues in Transaction Mechanism Design for Object Oriented Databases.” The document describes our ideas for extending the traditional transaction concept for use in object oriented databases, and concentrates specifically on providing an underlying model to support the concurrency control and version management aspects of the problem. The ideas presented here are not however restricted to the domain of object oriented databases. They are more generally applicable to database systems that require flexibility in their versioning and concurrency control policies.

In this document we define a …

Multiple Expert System, Umesh Kumar Mittal

Theses

In many domains, for example medical diagnosis, there are several sources of knowledge, e.g., several domain experts. These domain experts may have disagreements over some issues in the domain. Research in the area of human decision making suggests that a human decision is not always made based on the advice of a single expert. Many current expert systems, however, expect consistency in their knowledge bases. An expert system does not deliberate by reasoning that "on one hand..." but "on the other hand..." The knowledge engineer, who is not necessarily an expert in the same domain, ensures consistency by eliminating all …

Mechanical Parts Orienting: The Case Of A Polyhedron On A Table, Michael Erdmann, Matthew T. Mason, George Vanĕček

Department of Computer Science Technical Reports

No abstract provided.

Scheduling Support For An Internetwork Of Heterogeneous, Autonomous Processors, Steve Chapin, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.

Experiments In Concurrent Stochastic Simulation: The Eclipse Paradigm, Vernon J. Rego, V. S. Sunderam

Department of Computer Science Technical Reports

No abstract provided.

The Parallelization Of Level 2 And 3 Blas Operations On Distributed Memory Machines, M. Aboelaze, N. P. Chrisochoides, Elias N. Houstis, C. E. Houstis

Department of Computer Science Technical Reports

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, January 1991, 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.

Analyzing Images Containing Multiple Sparse Patterns With Neural Networks, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

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

We have addressed the problem of analyzing images containing multiple sparse overlapped patterns. This problem arises naturally when analyzing the composition of organic macromolecules using data gathered from their NMR spectra. Using a neural network approach, we have obtained excellent results in using NMR data to analyze the presence of various amino acids in protein molecules. We have achieved high correct classification percentages (about 87%) for images containing as many as five substantially distorted overlapping patterns.

Selection Networks, Nicholas Pippenger

All HMC Faculty Publications and Research

An upper bound asymptotic to $2n\log _e n$ is established for the number of comparators required in a network that classifies $n$ values into two classes, each containing $n / 2$ values, with each value in one class less than or equal to each value in the other. (The best lower bound known for this problem is asymptotic to $(n / 2)\log _2 n$.)

Performance Prediction For Distributed Load Balancing On Multicomputer Systems, Ishfaq Ahmed, Arif Ghafoor, Kishan Mehrotra

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

This paper presents a performance evaluation approach to compare different distributed load balancing schemes on a unified basis. This approach is an integration of simulation, statistical and analytical models, and takes into account the fundamental system parameters that can possibly affect the performance. We show that all the sender-initiated distributed load balancing strategies can be modeled by a central server open queuing network. Furthermore, these load balancing strategies can be characterized by only two queuing parameters – the average execution queue length and the probability that a newly arrived task is executed locally or migrated to another node. To capture …

Three--Dimensional Medical Imaging: Algorithms And Computer Systems, M. R. Stytz, G. Frieder, O. Frieder

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

This paper presents an introduction to the field of three-dimensional medical imaging It presents medical imaging terms and concepts, summarizes the basic operations performed in three-dimensional medical imaging, and describes sample algorithms for accomplishing these operations. The paper contains a synopsis of the architectures and algorithms used in eight machines to render three-dimensional medical images, with particular emphasis paid to their distinctive contributions. It compares the performance of the machines along several dimensions, including image resolution, elapsed time to form an image, imaging algorithms used in the machine, and the degree of parallelism used in the architecture. The paper concludes …

Optimal Parallel Lexicographic Sorting Using A Fine-Grained Decomposition, Ramachandran Vaidyanathan, Carlos R.P. Hartmann, Pramod Varshney

Electrical Engineering and Computer Science - Technical Reports

Though non-comparison based sorting techniques like radix sorting can be done with less "work" than conventional comparison-based methods, they are not used for long keys. This is because even though parallel radix sorting algorithms process the keys in parallel, the symbols in the keys are processed sequentially. In this report, we give an optimal algorithm for lexicographic sorting that can be used to sort n m-bit keys on an EREW model in Ө (log nlogm) time with Ө (mn) "work". This algorithm is not only as fast as any optimal non-comparison based algorithm, but can also be executed with less …

A Decentralized Task Scheduling Algorithm And Its Performance Modeling For Computer Networks, Ishfaq Ahmad, Arif Ghafoor, Kishan Mehrotra

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

A dynamic task scheduling algorithm, that is stable, de-centralized, and adaptive to network topology, is presented. The proposed algorithm is an extension of nearest neighbor load balancing strategy with an enhanced degree of efficiency and it is intended for multicomputers connected by a store and forward communication network. The proposed algorithm is modeled by a central server open queuing network. It is shown that the response time of a task consists of two parts. The first part comprises a task‘s settling time which consists of scheduling time, communication time, and waiting time in scheduling and communication queues. The second part …

Supereuleriaun Graphs And The Petersen Graph, Zhi-Hong Chen

Scholarship and Professional Work - LAS

Using a contraction method, we find some best-possible sufficient condi­tions for 3-edge-connected simple graphs such that either the graphs have spanning eulerian subgraphs or the graphs are contractible to the Petersen graph.

Transforming A Rule-Based Program, Rose F. Gamble

All Computer Science and Engineering Research

Conflict resolution is a form of global control used in production systems to achieve an efficient sequential execution of a rule-based program. This type of control is not used to parallel production system models [6,13]. Instead, only those programs that make no assumptions regarding conflict resolution are executed in parallel. Therefore, the initial sequential rule-based programs are either executed in parallel without their conflict resolution strategy, which normally results in incorrect behavior, or the programs are transformed in an ad hoc manner to execute on an particular parallel production system model. As a result, these programs do not exhibit the …