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Performance Modeling Of Load Balancing Algorithms Using Neural Networks, Ishfaq Ahmad, Arif Ghafoor, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Jan 1994

Performance Modeling Of Load Balancing Algorithms Using Neural Networks, Ishfaq Ahmad, Arif Ghafoor, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

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

This paper presents a new approach that uses neural networks to predict the performance of a number of dynamic decentralized load balancing strategies. A distributed multicomputer system using any distributed load balancing strategy is represented by a unified analytical queuing model. A large simulation data set is used to train a neural network using the back–propagation learning algorithm based on gradient descent. The performance model using the predicted data from the neural network produces the average response time of various load balancing algorithms under various system parameters. The validation and comparison with simulation data show that the neural network is …

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Scheduling Of Unstructured Communication On The Intel Ipsc/860, Jhy-Chun Wang, Sanjay Ranka Jan 1994

Scheduling Of Unstructured Communication On The Intel Ipsc/860, Jhy-Chun Wang, Sanjay Ranka

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

In this paper we present several algorithms for decomposing all-to-many personalized communication into a set of disjoint partial permutations. These partial permutations avoid node contention as well as link contention. We discuss the theoretical complexity of these algorithms and study their effectiveness both from the view of static scheduling and from runtime scheduling. Experimental results for our algorithms are presented on the iPSC/860.

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Tele-Assistance For Semi-Autonomous Robots, Erika Rogers, Robin R. Murphy Jan 1994

Tele-Assistance For Semi-Autonomous Robots, Erika Rogers, Robin R. Murphy

Computer Science and Software Engineering

This paper describes current work on a cooperative tele-assistance system for semi-autonomous robots. This system combines a robot architecture for limited autonomous perceptual and motor control with a knowledge-based operator assistant which provides strategic selection and enhancement of relevant data. The design of the system is presented, together with a number of exception-handling scenarios that were constructed as a result of experiments wit.h act.ual sensor data collected from two mobile robots.

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Simple Genetic Algorithms With Linear Fitness, Michael D. Vose, Alden H. Wright Jan 1994

Simple Genetic Algorithms With Linear Fitness, Michael D. Vose, Alden H. Wright

Computer Science Faculty Publications

A general form of stochastic search is described (random heuristic search), and some of its general properties are proved. This provides a framework in which the simple genetic algorithm (SGA) is a special case. The framework is used to illuminate relationships between seemingly different probabilistic perspectives of SGA behavior. Next, the SGA is formalized as an instance of random heuristic search. The formalization then used to show expected population fitness is a Lyapunov function in the infinite population model when mutation is zero and fitness is linear. In particular, the infinite population algorithm must converge, and average population …

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The Multigraph Modeling Tool, Amy Apon, C A. Childers, W H. Hooper, K D. Gordon, L W. Dowdy Jan 1994

The Multigraph Modeling Tool, Amy Apon, C A. Childers, W H. Hooper, K D. Gordon, L W. Dowdy

Publications

No abstract provided.

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Evolution In The Microprocessor Industry For Personal Computers: The Shift From Cisc Chips To Risc Chips, James Lamm Jan 1994

Evolution In The Microprocessor Industry For Personal Computers: The Shift From Cisc Chips To Risc Chips, James Lamm

Honors Theses, 1963-2015

The thesis examines the semiconductor industry, specifically focusing on microprocessor manufacturers for the personal computer market. The current technology in the industry, CISC microprocessors, have reached a price/performance limit. The industry is turning to RISC microprocessors for improved speed at lower costs. Intel, the current industry leader, is being challenged by AMD and Cyrix, who manufacture clones of Intel¹s microprocessors. In addition, Motorola, another giant in the industry, has teamed up with Apple and IBM to challenge Intel¹s dominance of the industry. Motorola is attempting to set a new microprocessor standard based on a RISC microprocessor, the Power PC. Intel …

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Genetic Algorithms For Soft Decision Decoding Of Linear Block Codes, Harpal Maini, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Jan 1994

Genetic Algorithms For Soft Decision Decoding Of Linear Block Codes, Harpal Maini, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

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

Soft-decision decoding is an NP-hard problem of great interest to developers of communication systems. We show that this problem is equivalent to the problem of optimizing Walsh polynomials. We present genetic algorithms for soft-decision decoding of binary linear block codes and compare the performance with various other decoding algorithms including the currently developed A* algorithm. Simulation results show that our algorithms achieve bit-error-probabilities as low as 0:00183 for a [104; 52] code with a low signal-to-noise ratio of 2:5 dB, exploring only 22; 400 code words, whereas the search space contains 4:5 \Theta 10 15 codewords. We define a new …

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Passion Runtime Library For Parallel I/O, Rajeev Thakur, Rajesh Bordawekar, Alok Choudhary, Ravi Ponnusamy Jan 1994

Passion Runtime Library For Parallel I/O, Rajeev Thakur, Rajesh Bordawekar, Alok Choudhary, Ravi Ponnusamy

Electrical Engineering and Computer Science - All Scholarship

We are developing a compiler and runtime support system called PASSION: Parallel And Scalable Software for Input-Output. PASSION provides software support for I/O intensive out-of-core loosely synchronous problems. This paper gives an overview of the PASSION Runtime Library and describes two of the optimizations incorporated in it, namely Data Prefetching and Data Sieving. Performance improvements provided by these optimizations on the Intel Touchstone Delta are discussed, together with an out of -core Median Filtering application.

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Logic Simulation Using An Asynchronous Parallel Discrete-Event Simulation Model On A Simd Machine, Sharad C. Seth, Lee Gowen, Matt Payne, Don Sylwester Jan 1994

Logic Simulation Using An Asynchronous Parallel Discrete-Event Simulation Model On A Simd Machine, Sharad C. Seth, Lee Gowen, Matt Payne, Don Sylwester

School of Computing: Conference and Workshop Papers

The Chandy-Misra-Bryant (CMB) model has been applied to logic simulation of synchronous sequential circuits using a massively parallel SIMD computer, a CM-2 Connection Machine. Several methods of reducing message traffic in a logic simulation have been adapted to the SIMD architecture of the CM-2, with the result that each method of reducing message traffic actually decreases the speed of the simulation. This suggests that communication costs required to support logic simulation are small compared to the cost of deciding which messages need not be sent.

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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 1, January 1994, College Of Engineering And Computer Science, Wright State University Jan 1994

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 1, January 1994, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

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Learning One-Dimensional Geometric Patterns Under One-Sided Random Misclassification Noise, Paul W. Goldberg, Sally A. Goldman Jan 1994

Learning One-Dimensional Geometric Patterns Under One-Sided Random Misclassification Noise, Paul W. Goldberg, Sally A. Goldman

All Computer Science and Engineering Research

Developing the ability to recognize a landmark from a visual image of a robot's current location is a fundamental problem in robotics. We consider the problem of PAC-learning the concept class of geometric patterns where the target geometric pattern is a configuration of k points on the real line. Each instance is a configuration of n points on the real line, where it is labeled according to whether or not it visually resembles the target pattern. To capture the notion of visual resemblance we use the Hausdorff metric. Informally, two geometric patterns P and Q resemble each othe runder the …

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Rationales And Argument Moves, R. P. Loui, Jeff Norman Jan 1994

Rationales And Argument Moves, R. P. Loui, Jeff Norman

All Computer Science and Engineering Research

No abstract provided.

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Congestion Control In Atm Networks, Apostolos Dailianas, Andreas Bovopoulos Jan 1994

Congestion Control In Atm Networks, Apostolos Dailianas, Andreas Bovopoulos

All Computer Science and Engineering Research

No abstract provided.

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Self-Stabilization By Counter Flushing, George Varghese Jan 1994

Self-Stabilization By Counter Flushing, George Varghese

All Computer Science and Engineering Research

A useful way to design simple and robust protocols is to make them self-stabilitizing. We describe a simple technique for self-stabilization called counter flushign which is applicable to a number of distributed algorithms. A randomized version of counter flushing is shown to have extremely small expected stabilization time. We show how our technique helps to crisply understand and improve some previous distributed algorithms. Then we apply it to a variety of total algorithms for deadlock detection, propagation of information with feedback, resets and snapshots. Our stabilizing snapshot protocol has much better complexity than the previous stabilizing non-blocking snapshot protocol. Hence …

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Strategies For The Parallel Training Of Simple Recurrent Neural Networks, Peter J. Mccann, Barry L. Kalman Jan 1994

Strategies For The Parallel Training Of Simple Recurrent Neural Networks, Peter J. Mccann, Barry L. Kalman

All Computer Science and Engineering Research

Two concurrent implementations of the method of conjugate gradients for training Elman networks are discussed. The parallelism is obtained in the computation of the error gradient and the method is therefore applicable to any gradient descent training technique for this form of network. The experimental results were obtained on a Sun Sparc Center 2000 multiprocessor. The Sparc 2000 is a shared memory machine well suited to coarse-grained distributed computations, but the concurrency could be extended to other architectures as well.

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Trading Packet Headers For Packet Processing, George Varghese Jan 1994

Trading Packet Headers For Packet Processing, George Varghese

All Computer Science and Engineering Research

In high speed networks, packet processing is relatively expensive while bandwidth is cheap. This begs the question: what fields can be added to packets to make packet processing easier? By exploring this question, we device a number of novel mechanisms to speed up packet processing. With the advent of new standards for hte Data Link, Network, and Transport lyaers, we believe there is an opportunity to apply these techniques to improve the performance of real protocols. First, we suggest adding a data manipulation header to an easily accessible portion of each packet. This header contains pointers to fields (in various …

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Efficient Fair Queueing Using Deficit Round Robin, George Varghese, M. Shreedhar Jan 1994

Efficient Fair Queueing Using Deficit Round Robin, George Varghese, M. Shreedhar

All Computer Science and Engineering Research

Fair queuing is a technique that allows each flow passing through a network device to have fair share of network resources. previous schemes for fair queuing that achieved nearly perfect fairness were expensive to implement: specifically, the work required to process a packet in these schemes was O(log(n)), where n is the number of active flows. This is expensive at high speeds. On the other hand, cheaper approximations of fair queuing that have been reported in the literature exhibit unfair behavior. In this paper, we describe a new approximation of fair queuing, that we call Deficit Round Robin. Our scheme …

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Exact Learning Of Discretized Geometric Concepts, Nader H. Bshouty, Paul W. Goldberg, Sally A. Goldman, H. David Mathias Jan 1994

Exact Learning Of Discretized Geometric Concepts, Nader H. Bshouty, Paul W. Goldberg, Sally A. Goldman, H. David Mathias

All Computer Science and Engineering Research

We first present an algorithm that uses membership and equivalence queries to exactly identify a discretized geometric concept defined by the unioin of m axis-parallel boxes in d-dimensional discretized Euclidean space where each coordinate can have n discrete values. This algorithm receives at most md counterexamples and uses time and membership queries polynomial in m and log(n) for any constant d. Furthermore, all equivalence queries can be formulated as the union of O(mdlog(m)) axis-parallel boxes. Next, we show how to extend our algorithm to efficiently learn, from only equivalence queries, any discretized geometric concept generated from any number of halfspaces …

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Learning From A Consistently Ignorant Teacher, Michael Frazier, Sally Goldman, Nina Mishra, Leonard Pitt Jan 1994

Learning From A Consistently Ignorant Teacher, Michael Frazier, Sally Goldman, Nina Mishra, Leonard Pitt

All Computer Science and Engineering Research

One view of computational learning theory is that of a learner acquiring the knowledge of a teacher. We introduce a formal model of learning capturing the idea that teachers may have gaps in their knowledge. The goal of the learner is still to acquire the knowledge of the teacher, but now the learner must also identify the gaps. This is the notion of learning from a consistently ignorant teacher. We consider the impact of knowledge gaps on learning, for example, monoton DNF and d-dimensional boxes, and show that leraning is still possible. Negatively, we show that knowledge gaps make learning …

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Cmap, Ken Cox, John Dehart Jan 1994

Cmap, Ken Cox, John Dehart

All Computer Science and Engineering Research

This document specifies a Connection Management Access Protocol (CMAP) for call management in high-speed packet switched networks. We target CMAP to networks employing the Asynchronous Transfer Mode (ATM) communication standard. CMAP specifies the access procedues exercised by network clients to manipulate multipoint calls; it is thus a User-Network Interface (UNI) signalling protocol. We define a multipoint call as a group of multipoint connections. A multipoint connection is a communication channel between two or more clients or endpoints of the network, where all data sent by one client is received by all other clients who have elected to receive. A point-to-point …

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Cell Tracking Using A Distributed Algorithm For 3d Image Segmentation, Vikas Awasthi, Keith W. Doolittle, Guru Parulkar, James G. Mcnally Jan 1994

Cell Tracking Using A Distributed Algorithm For 3d Image Segmentation, Vikas Awasthi, Keith W. Doolittle, Guru Parulkar, James G. Mcnally

All Computer Science and Engineering Research

We have developed and tested an automated method for simultaneous 3D tracking of numerous, flourescently-tagged cells. The procedure uses multiple thresholding to segment individual cells at a starting timepoint, and then iteratively applies a template-matching algorithm to locate a particular cell's position at subsequent time points. To speed up the method, we have developed a distributed implementation in which template matching is carried out in parallel on several different server machines. The distributed implementation showed a monotonic decrease in response time with increasing number of servers (up to 15 tested), demonstrating that the tracking algorithm is well suited to parallelization, …

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Design Of A Large Scale Multimedia Server, Milind M. Buddhikot, Guru Parulkar, Jerome R. Cox Jr. Jan 1994

Design Of A Large Scale Multimedia Server, Milind M. Buddhikot, Guru Parulkar, Jerome R. Cox Jr.

All Computer Science and Engineering Research

Large scale multimedia storage servers will be an integral part of the emerging distributed multimedia computing infrastructure. However, given the modest rate of improvements in storage transfer rates, designing servers that meet the demands of multimedia applications is a challenging task that needs significant architectural innovation. Our research project, called Massively-parallel And Real-time Storage (MARS) architecture, is aimed at the design and prototype implementation of a large scale multimedia storage server. It uses some of the well-known techniques in parallel I/O, such as data striping and Redundant Arrays of Inexpensive Disks (RAID) and an innovative ATM based interconnect inside the …

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Visual Specification Of Interprocess And Intraprocess Communication, T. Paul Mccartney, Kenneth J. Goldman Jan 1994

Visual Specification Of Interprocess And Intraprocess Communication, T. Paul Mccartney, Kenneth J. Goldman

All Computer Science and Engineering Research

We present a visual specification language for constructing distributed applications and their direct manipulation graphical user interfaces. Each distributed application consists of a collection of independent modules and a configuration of logical connections that define communication among the data interfaces of the modules. Our specification language uses a single visual mechanism that allows end-users to define interprocess communication among distributed modules and to define intraprocess communication among objects within a module. This seamless specification provides a general encapsulation/abstraction mechanism and is designed to support dynamic change to the communication structure. User interfaces are completely decoupled from the module(s) they control.

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Efficient Quality Of Service Support In Multimedia Computer Operating Systems, Raman Gopalakrishna, Guru M. Parulkar Jan 1994

Efficient Quality Of Service Support In Multimedia Computer Operating Systems, Raman Gopalakrishna, Guru M. Parulkar

All Computer Science and Engineering Research

This report describes our approach towards providing quality of service (QoS) guarantees for network communication within the endsystems to support multimedia applications. We first address the problem of QoS specification by identifying a set of application classes and their QoS parameters that cover the communication requirements of most applications. We then describe the QoS mapping problem, and show how requirements for resources (such as the CPU, the network interface adaptor and network connections) can be automatically derived from the application QoS parameters. We then deal with the QoS enforcement issue in which we describe techniques for scheduling protocol processing threads …

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Catching Up With The Networks: Host I/O At Gigabit Rates, Zubin D. Dittia, Jerome R. Cox Jr., Guru M. Parulkar Jan 1994

Catching Up With The Networks: Host I/O At Gigabit Rates, Zubin D. Dittia, Jerome R. Cox Jr., Guru M. Parulkar

All Computer Science and Engineering Research

The last few years have seen network data rates skyrocket from a few Mbps to a Gbps or more. However, a lack of integration of the host-netowrk interface, the operating system, and network protocols has resulted in end-applications seeing only a small fraction of this total bandwidth being available for data transfer. The emergence of demanding applications in the realms of multimedia and virtual reality provides further impetus in the drive to overcome this problem. In this paper, we present the design of a high performance ATM host-network interface for workstations and servers that can support a bidirecitonal sustained data …

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Pipelined And Superscalar Architectures In Clocked And Asynchronous Environments, Mark A. Franklin, Tienyo Pan Jan 1994

Pipelined And Superscalar Architectures In Clocked And Asynchronous Environments, Mark A. Franklin, Tienyo Pan

All Computer Science and Engineering Research

In this paper, a set of simple, general, yet practical performance models for RISC architectures are developed. These models apply to a wide range of systems that include both pipelined and superscalar systems operating in either clocked or asynchronous environments. The models permit quantitative evaluation of various design choices (e.g., the number of pipelines in the system, the pipeline depth, and the choice between clocked and asynchronous methodologies) as functions of technology parameters, environmental operating parameters, and pipeline function characteristics. Design curves are presented indicating optimal pipeline depth and number of pipelines to employ under various conditions.

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Morphing Binary Trees, John Hershberger, Subhash Suri Jan 1994

Morphing Binary Trees, John Hershberger, Subhash Suri

All Computer Science and Engineering Research

We investigate the problem of transforming one binary tree into another by rotatoins, subject to certain weight ocnstraints on the nodes of the trees. These constraints arise in the problem of "morphing" one simple polygon to another simple polygon by continuous deformatinos (translations and scalings) that preserve the turn angles and the simplicity of the polygon; the two polygons must have the same sequence of turn angles. Our main theorem is that two arbitrary n-leaf binary trees satisfying our weight constraint can be morphed into each other with O(n log n) rotations. Furthermore, we also present an O(n log n) …

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Distributed Data Layout, Scheduling And Playout Control In A Large Scale Multimedia Storage Server, Milind M. Buddhikot, Guru Parulkar Jan 1994

Distributed Data Layout, Scheduling And Playout Control In A Large Scale Multimedia Storage Server, Milind M. Buddhikot, Guru Parulkar

All Computer Science and Engineering Research

No abstract provided.

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High-Performance Training Of Feedforward & Simple Recurrent Networks, Barry L. Kalman, Stan C. Kwasny Jan 1994

High-Performance Training Of Feedforward & Simple Recurrent Networks, Barry L. Kalman, Stan C. Kwasny

All Computer Science and Engineering Research

TRAINREC is a system for training feedforward and recurrent neural networks that incorporates several ideas. It uses the conjugate-gradient method which is demonstrably more efficient than traditional backward error propagation. We assume epoch-based training and derive a new error function having several desirable properties absent from the traditional sum-of-squared-error function. We argue for skip (shortcut) connections where appropriate and the preference for a sigmoidal yielding values over the [-1,1] interval. The input feature space is often over-analyzed, but by using singular value decomposition, input patterns can be conditioned for better learning often with a reduced number of input units. Recurrent …

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Universal Continuous Media I/O: Design And Implementation, Charles D. Cranor, Gurudatta M. Parulkar Jan 1994

Universal Continuous Media I/O: Design And Implementation, Charles D. Cranor, Gurudatta M. Parulkar

All Computer Science and Engineering Research

The problem this paper addresses is how to modify an existing operating system's I/O subsystem to support new high-speed networks and high-bandwidth multimedia applications that will play an important role in future computing environments. The proposed I/O subsystem is called universal continuous media I/O (UCM I/O). This paper will cover the preliminary design of UCM I/O, some of the trade-offs and issues that need to be addressed in order to implement UCM I/O, and a summary of work in progress.

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