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Linear Codes And Error-Correction, Karen Brown Jan 1994

Linear Codes And Error-Correction, Karen Brown

Presidential Scholars Theses (1990 – 2006)

The process of encoding information for transmission from one source to another is a vital process in many areas of science and technology. Whenever coded information is sent, there arises a certain possibility that an error will occur, either during transmission or in decoding. Therefore, it is imperative to develop methods to detect and correct errors in a code. The study of coding theory is a "new" area of mathematics which is relatively undeveloped.

This paper focuses on the properties of linear codes -and their corresponding methods of error-correction. To simplify the issue, only binary block codes are studied; hence …


Job Scheduling In Rings, Perry Fizzano, Clifford Stein, David Karger, Joel Wein Jan 1994

Job Scheduling In Rings, Perry Fizzano, Clifford Stein, David Karger, Joel Wein

Computer Science Technical Reports

We give distributed approximation algorithms for job scheduling in a ring architecture. In contrast to almost all other parallel scheduling models, the model we consider captures the influence of the underlying communications network by specifying that task migration from one processor to another takes time proportional to the distance between those two processors in the network. As a result, our algorithms must balance both computational load and communication time.

The algorithms are simple, require no global control, and work in a variety of settings. All come with small constant-factor approximation guarantees; the basic algorithm yields schedules of length at most …


Scheduling In A Ring With Unit Capacity Links, Perry Fizzano, Clifford Stein Jan 1994

Scheduling In A Ring With Unit Capacity Links, Perry Fizzano, Clifford Stein

Computer Science Technical Reports

We consider the problem of scheduling unit-sized jobs on a ring of processors with the objective of minimizing the completion time of the last job. Unlike much previous work we place restrictions on the capacity of the network links connecting processors. We give a polynomial time centralized algorithm that produces optimal length schedules. We also give a simple distributed 2-approximation algorithm.


Asymptotically Tight Bounds For Performing Bmmc Permutations On Parallel Disk Systems, Thomas H. Cormen, Thomas Sundquist, Leonard F. Wisniewski Jan 1994

Asymptotically Tight Bounds For Performing Bmmc Permutations On Parallel Disk Systems, Thomas H. Cormen, Thomas Sundquist, Leonard F. Wisniewski

Computer Science Technical Reports

We give asymptotically equal lower and upper bounds for the number of parallel I/O operations required to perform bit-matrix-multiply/complement (BMMC) permutations on parallel disk systems. In a BMMC permutation on N records, where N is a power of 2, each (lg N)-bit source address x maps to a corresponding (lg N)-bit target address y by the matrix equation y = Ax XOR c, where matrix multiplication is performed over GF(2). The characteristic matrix A is (lg N) x (lg N) and nonsingular over GF(2). Under the Vitter-Shriver parallel-disk model with N records, D disks, B records per block, and M …


The Design And Development Of Interactive Multimedia Conference Proceedings, Samuel A. Rebelsky, James Ford, Kenneth Harker, Fillia Makedon, P Takis Metaxas, Charles Owen Jan 1994

The Design And Development Of Interactive Multimedia Conference Proceedings, Samuel A. Rebelsky, James Ford, Kenneth Harker, Fillia Makedon, P Takis Metaxas, Charles Owen

Computer Science Technical Reports

Many conferences are now providing electronic proceedings. Often, these proceedings are little more than electronic collections of documents put together in a standard software package, such as SuperBook or Acrobat. This means that few of these proceedings incorporate the full range of materials that a conference generates. Furthermore, because these general interfaces are not designed for conference proceedings, they do not provide all the features a conference warrants.

The interactive multimedia proceedings for the DAGS'92 Institute on Parallel Computation used an interface designed specifically for presenting conference materials and provided both talks (audio, video, and slides) and papers (in hypertext …


Determination Of Budgetary Expertise Among Public School Library Media Specialists In The State Of Florida, Mary Hosken Jan 1994

Determination Of Budgetary Expertise Among Public School Library Media Specialists In The State Of Florida, Mary Hosken

CCAC Theses and Dissertations

In 1988, Information Power described skills and duties expected of a school library media specialist. These include familiarity with various forms of educational technology, interpersonal social and communication skills, and proficiency in a wide range of planning and management areas. Simultaneously, restructuring, a movement to site-based management, requires new types of skills of Florida's teachers.

While the importance and complexity of the position of library media specialist has increased, there is concern that some practicing professionals do not have training or experience to address these new obligations. As a benchmark of current expertise in non-instructional duties, this research effort attempted …


A Strategic Plan For Computing And Telecommunications At A University, Dennis J. Huff Jan 1994

A Strategic Plan For Computing And Telecommunications At A University, Dennis J. Huff

CCAC Theses and Dissertations

Embry-Riddle Aeronautical University (ERAU), a multi-campus, four-year institution of higher education specializing in aeronautic and avionic engineering, has recently made a strong commitment to integration of technology into the University environment. Due to a present lack of vision and planning, ERAU secured the services of Technology Specialists, Inc. (TSI) to manage the technology center and develop a five year plan for technology integration. The author was instrumental in the planning and development of the plan. As research has confirmed, technology planning has traditionally been lacking in higher education institutions. The author followed a method for plan development as suggested by …


The Electronic Bulletin Board As A Means Of Professional Communication Among Physics Teachers, Donald L. Mcgarry Jan 1994

The Electronic Bulletin Board As A Means Of Professional Communication Among Physics Teachers, Donald L. Mcgarry

CCAC Theses and Dissertations

Teachers of secondary school physics are often physically isolated from their peers; that is, they do not have as much contact with their physics colleagues as they desire. One reason for this physical isolation is the relatively small population of students enrolled in high school physics courses resulting in small numbers of physics teachers per school. Another is that many physics teachers are teaching physics only part time.

One method of communication among teachers has the potential to improve professional communication among physics teachers. This is the computer operated electronic bulletin board system (BBS). Bulletin board systems and variants have …


The Design Of An Effective, Economical Executive Information System For Cedarville College, David L. Rotman Jan 1994

The Design Of An Effective, Economical Executive Information System For Cedarville College, David L. Rotman

CCAC Theses and Dissertations

The managers of a corporation have an obligation to make the best use of available organizational resources for daily operational activities of the corporation and for long-range development. This requirement for efficient management certainly obtains for higher education, as declining student populations and shrinking funding sources argue for an even greater need to manage well. One important aspect of efficient management is having sufficient information for decision making. This dissertation addresses the need for electronic tools to assist officers of a higher education institution in the management of the institution by improving access to information. College administrators need information about …


Generalized Ffts - A Survey Of Some Recent Results, David K. Maslen, Daniel N. Rockmore Jan 1994

Generalized Ffts - A Survey Of Some Recent Results, David K. Maslen, Daniel N. Rockmore

Dartmouth Scholarship

In this paper we survey some recent work directed towards generalizing the fast Fourier transform (FFT). We work primarily from the point of view of group representation theory. In this setting the classical FFT can be viewed as a family of efficient algorithms for computing the Fourier transform of either a function defined on a finite abelian group, or a bandlimited function on a compact abelian group. We discuss generalizations of the FFT to arbitrary finite groups and compact Lie groups.


Financial Aid Budget Projection Methodology, Amy N. Baird '94 Jan 1994

Financial Aid Budget Projection Methodology, Amy N. Baird '94

Honors Projects

The nature of this research project is to make a very strong contribution toward the final goal of completely automating the Financial Aid Office at Illinois Wesleyan University over the next five years.


Neural Network Diagnosis Of Malignant Melanoma From Color Images, Fikret Erçal, Hsi-Chieh Lee, William V. Stoecker, Randy Hays Moss, Anurag Chawla Jan 1994

Neural Network Diagnosis Of Malignant Melanoma From Color Images, Fikret Erçal, Hsi-Chieh Lee, William V. Stoecker, Randy Hays Moss, Anurag Chawla

Computer Science Faculty Research & Creative Works

Malignant melanoma is the deadliest form of all skin cancers. Approximately 32,000 new cases of malignant melanoma were diagnosed in 1991 in the United States, with approximately 80% of patients expected to survive 5 years. Fortunately, if detected early, even malignant melanoma may be treated successfully, Thus, in recent years, there has been rising interest in the automated detection and diagnosis of skin cancer, particularly malignant melanoma. Here, the authors present a novel neural network approach for the automated separation of melanoma from 3 benign categories of tumors which exhibit melanoma-like characteristics. The approach uses discriminant features, based on tumor …


The World Wide Web And Technology Transfer At Nasa Langley Research Center, Michael L. Nelson, David J. Bianco Jan 1994

The World Wide Web And Technology Transfer At Nasa Langley Research Center, Michael L. Nelson, David J. Bianco

Computer Science Faculty Publications

NASA Langley Research Center (LaRC) began using the World Wide Web (WWW) in the summer of 1993, becoming the first NASA installation to provide a Center-wide home page. This coincided with a reorganization of LaRC to provide a more concentrated focus on technology transfer to both aerospace and non-aerospace industry. Use of the WWW and NCSA Mosaic not only provides automated information dissemination, but also allows for the implementation, evolution and integration of many technology transfer applications. This paper describes several of these innovative applications, including the on-line presentation of the entire Technology Opportunities Showcase (TOPS), an industrial partnering showcase …


A Strategy For Electronic Dissemination Of Nasa Langley Technical Publications, Donna G. Roper, Mary K. Mccaskill, Scott D. Holland, Joanne L. Walsh, Michael L. Nelson, Susan L. Adkins, Manjula Y. Ambur, Bryan A. Campbell Jan 1994

A Strategy For Electronic Dissemination Of Nasa Langley Technical Publications, Donna G. Roper, Mary K. Mccaskill, Scott D. Holland, Joanne L. Walsh, Michael L. Nelson, Susan L. Adkins, Manjula Y. Ambur, Bryan A. Campbell

Computer Science Faculty Publications

To demonstrate NASA Langley Research Center's relevance and to transfer technology to external customers in a timely and efficient manner, Langley has formed a working group to study and recommend a course of action for the electronic dissemination of technical reports (EDTR). The working group identified electronic report requirements (e.g., accessibility, file format, search requirements) of customers in U.S. industry through numerous site visits and personal contacts. Internal surveys were also used to determine commonalities in document preparation methods. From these surveys, a set of requirements for an electronic dissemination system was developed. Two candidate systems were identified and evaluated …


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.


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.


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 …


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.


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 …


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 …


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 …


Performance Comparison Of Asynchronous Adders, Mark A. Franklin, Tienyo Pan Jan 1994

Performance Comparison Of Asynchronous Adders, Mark A. Franklin, Tienyo Pan

All Computer Science and Engineering Research

In asynchronous systems, average function delays principally govern overall throughput. This paper compares the performance of six adder designs with respect to their average delays. Our results show that asynchronous addres (32 or 64-bits) with a hybrid structure (e.g., carry-select addres) run 20-40% faster than simple ripple-carry addres. Hybrid adders also outperform high-cost, strictly synchronous conditional-sum adders.


Speculative Computation: Overcoming Communication Delays In Parallel Algorithms, Vasudha Govindan, Mark A. Franklin Jan 1994

Speculative Computation: Overcoming Communication Delays In Parallel Algorithms, Vasudha Govindan, Mark A. Franklin

All Computer Science and Engineering Research

Communication latencies and delays are a major source of performance degradation in parallel computing systems. It is importnat to "mask" these communication delays by overlapping them with useful computation in order to obtain good parallel performance. This paper proposes speculative computation as a technique to mask communication latencies. Speculative computation is discussed in the context of synchronous iterative algorithms. Processors speculate the contents of messages that are not hyet received and perform computation based on the speculated values. When the messages are received, they are compared with the speculated values and, if the error is unacceptable, the resulitng computation is …


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 …


Practical Methods For Approximating Shortest Paths On A Convex Polytope In R3, John Hershberger, Subhash Suri Jan 1994

Practical Methods For Approximating Shortest Paths On A Convex Polytope In R3, John Hershberger, Subhash Suri

All Computer Science and Engineering Research

We propose a n extremely simple approximation scheme for computing shortest paths on the surface of a convex polytope in three dimensions. Given a convex polytope P with n vertices and two points p,q on its surface, let dp (p,q) denote the shortest path distance between p and q on the surface of P. Our algorithm produces a path of length at most 2 × dp(p,q) in time O(n). Extending this results, we can also compute ana pproximation of the shortest path tree rooted at an arbitrary point χ Є P in time O(n log n). In the approximate tree, …


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 …


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.


Reasoning About Places, Times, And Actions In The Presence Of Mobility, C. Donald Wilcox, Gruia-Catalin Roman Jan 1994

Reasoning About Places, Times, And Actions In The Presence Of Mobility, C. Donald Wilcox, Gruia-Catalin Roman

All Computer Science and Engineering Research

The current trend toward portable computing systems (e.g., cellular phones, laptop computers) brings with it the need for a new paradigm for thinking about designing distributed applications. We introduce the term mobile to refer to distributed systems that include moving, autonomous agents which loosely cooperate to accomplish a tastk. The fluid nature of hte interconnections between components in a mobile system provides new challenges and new opportunities for the research community. While we do not propsoe to have fully grasped the consequences of these systems, we believe that the notions of place, time, and action will be central in any …


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.


An Evaluation Of The Pavane Visualization System, Kenneth C. Cox, Gruia-Catalin Roman Jan 1994

An Evaluation Of The Pavane Visualization System, Kenneth C. Cox, Gruia-Catalin Roman

All Computer Science and Engineering Research

The Pavane program visualization system is an implementation of the declarative paradigm of visualization. After a brief report on the status of the Pavane implementation, we present the results of an evaluation of the usability of Pavane. This evaluation is based on the use of Pavane by its developers to construct program visualizations, on its use in a classroom setting as a tool for examining executing programs, and on its application to some simple scientific visualizations.