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Ua66/3/2 Computer Science Alumni Newsletter, Vol. 6, Wku Computer Science

WKU Administration Documents

Newsletter created by WKU Computer Science for alumni of the program.

Performance Prediction For Distributed Load Balancing In Multicomputer Systems, Ishfaq Ahmad, Arif Ghafoor, Kishan Mehrotra

Electrical Engineering and Computer Science - Technical Reports

Computing literature has being flooded recently with a plethora of dynamic load balancing strategies for multicomputer systems. The diversity of many strategies and their dependence on a number of parameters has made it difficult to compare their effectiveness on a unified basis. Not only does each strategy consider a different environment, but the simplified assumptions obscure the relative merits and demerits of each strategy. This paper presents a solution to compare different load balancing schemes on a unified basis. Our approach, which is an integration of simulation, statistical and analytical experiments, takes into account the fundamental system parameters that can …

On Serializability Of Multidatabase Transactions Through Forced Local Conflict, Dimitrios Georgakopoulos, Marek Rusinkiewicz, Amit P. Sheth

Kno.e.sis Publications

The main difficulty in enforcing global serializability in a multidatabase environment lies in resolving indirect transitive conflicts between multidatabase transactions. Indirect conflicts introduced by local transactions are difficult to resolve because the behavior or even the existence of local transactions is not known to the multidatabase system. To overcome these problems, we propose to incorporate additional data manipulation operations in the subtransactions of each multidatabase transaction. We show that if these operations create direct conflicts between subtransactions at each participating local database system, indirect conflicts can be resolved even if the multidatabase system is not aware of their existence. Based …

Simulator For Concurrent Processing Data Flow Architectures, Mahyar R. Malekpour

Electrical & Computer Engineering Theses & Dissertations

A software simulator capable of simulating execution of an algorithm graph on a given system under the Algorithm To Architecture Mapping Model (ATAMM) rules is presented in this thesis. ATAMM is capable of modeling the execution of large-grained algorithms on distributed data flow architectures. Investigating the behavior and determining the performance of an ATAMM based system requires the aid of software tools. The ATAMM Simulator presented in this thesis is capable of determining the behavior, performance, and reliability of a system without having to build a hardware prototype. Case studies are performed on four algorithms to demonstrate the capabilities of …

A Parallel Algorithm For Computing Invariants Of Petri Net Models, Dan C. Marinescu, Mike Beaven, Ryan Stansifer

Department of Computer Science Technical Reports

No abstract provided.

Interoperability In Multidatabase Systems, Omran A. Bukhres, Ahmed K. Elmagarmid

Department of Computer Science Technical Reports

No abstract provided.

Transaction Models For Advanced Database Applications, Ahmed K. Elmagarmid

Department of Computer Science Technical Reports

No abstract provided.

Relax: A Software Platform For Pde Interface Relaxation Methods, Scott Mcfaddin, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

Global Commitment In Multidatabase Systems, Ahmed K. Elmagarmid, Jin Jing, Won Kim

Department of Computer Science Technical Reports

No abstract provided.

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.

The N-Body Pipeline, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

A general pipeline for all-pairs computations is adapted for direct force summation of n bodies which interact through gravitation only. To achieve approximate load balance the pipeline is folded several times across an array of processors. The performance of the pipeline is analyzed and measured on a Computing Surface.

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, …

Analyzing Availability Of Replicated Database Systems, Bharat Bhargava, Abdelsalam Helal, Karl Friesen

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 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 …

Evolution Of A Communication System For Distributed Transaction Processing In Raid, Bharat Bhargava, Yongguang Zhang, Enrique Mafla

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.

Asymptotic Properties Of Data Compressions And Suffix Trees, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

Performance Of Pde Sparse Solvers On Hypercubes, Mo Mu, John R. Rice

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.

Scatter Scheduling For Problems With Unpredictable Structures, Min-You Wu, Wei Shu

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

An extended scatter scheduling was applied to problems with unpredictable, asynchronous structures. It has been found that with this simple scheduling strategy, good load balance can be reached without incurring much runtime overhead. This scheduling algorithm has been implemented on hypercube machines, and its performance is compared with other scheduling strategies.

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 …

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 …

Implementing A Neural Network In The Smalltalk Graphical Environment, John M. Damgaard

Presidential Scholars Theses (1990 – 2006)

Interest in artificial neural networks has grown rapidly over the past few years. The technology is intriguing and the potential applications of the technology are exciting and diverse. Another area of growing interest in the computer science field is that of object-oriented programming. The object-oriented paradigm is a very powerful tool which can improve software quality and streamline the development process. The most common object-oriented language is Smalltalk. I feel that Smalltalk is an excellent platform on which to implement artificial neural networks.

Curriculum-Oriented Cai Based On Instructional Technology To Be Used For Teaching Secondary School Students Introductory Library Skills, Theresa K. Toohil

CCAC Theses and Dissertations

In 1990, the New York State Education Department presented a syllabus that required the teaching of curriculum-oriented library skills and suggested the use of computers to be integrated with the teaching of these skills whenever possible. Schools in New York State are now trying to implement the suggestions in the syllabus. Many authors of educational articles have written at length concerning the incorporation of computer-assisted instruction (CAl) into the classroom, but clear directions have not been provided in the literature for the design or implementation of the necessary software.

The purpose of this study was to design a program based …