Digital Commons Network^™

Efficient Geometric Algorithms In The Erew-Pram, Danny Z. Chen

Department of Computer Science Technical Reports

No abstract provided.

Ua66/3/2 Computer Science Alumni Newsletter, Vol. 5, Wku Computer Science

WKU Administration Documents

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

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

On The Height Of Digital Trees And Related Problems, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

A Hierarchical Approach To Concurrency Control For Multidatabases, Ahmed K. Elmagarmid, Yunhho Leu

Department of Computer Science Technical Reports

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, October 1989, 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.

High Rate Concatenated Coding Systems Using Multidimensional Bandwidth Efficient Inner Codes, Robert H. Deng, Daniel J. Jr. Costello

Research Collection School Of Computing and Information Systems

A concatenated coding system using two-dimensional trellis-coded MPSK inner codes and Reed-Solomon outer codes for application in high-speed satellite communication systems was proposed previously by the authors (ibid., vol.37, no.5, p.420-7, May 1989). The authors extend their results to systems using symbol-oriented, multidimensional, trellis-coded MPSK inner codes. The concatenated coding systems are divided into two classes according to their achievable effective information rates. The first class uses multidimensional trellis-coded 8-PSK inner codes and achieves effective information rates around 1 b/dimension (spectral efficiency 2 b/s/Hz). The second class employs multidimensional trellis-coded 16-PSK inner codes and provides effective information rates around 1.5 …

Design Considerations For Distributed Scientific Software Systems, Paul E. Buis

Department of Computer Science Technical Reports

No abstract provided.

Analysis Of Digital Tries With Markovian Dependency, P. Jacquet, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

A Note On The Height Of Suffix Trees, Luc Devroye, Wojciech Szpankowski, Bonita Rais

Department of Computer Science Technical Reports

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, September 1989, 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.

Optimal Canonization Of All Substrings Of A String, A. Apostolico, M. Crochemore

Department of Computer Science Technical Reports

No abstract provided.

Implementing Object Support In The Raid Distributed Database System, Bharat Bhargava, Prasun Dewar, James G. Mullen, Jagannathan Srinivasan

Department of Computer Science Technical Reports

No abstract provided.

Embedding Meshes On The Star Graph, Sanjay Ranka, Jhy-Chun Wang, Nangkang Yeh

Electrical Engineering and Computer Science - Technical Reports

We develop algorithms for mapping n-dimensional meshes on a star graph of degree n with expansion 1 and dilation 3. We show that an n degree star graph can efficiently simulate an n-dimensional mesh.

Multiple Network Embeddings Into Hypercubes, Ajay K. Gupta, Susanne E. Hambrusch

Department of Computer Science Technical Reports

No abstract provided.

An O(H^6) Quintic Spline Collocation Method For Second Order Two-Point Boundary Value Problems, M. Irodotou-Ellina, Elias N. Houstis, S. B. Kim

Department of Computer Science Technical Reports

No abstract provided.

Parity Retransmission Hybrid Arq Using Rate 1/2 Convolutional Codes On A Nonstationary Channel, L. R. Lugand, D. J. Costello, Jr., Robert H. Deng

Research Collection School Of Computing and Information Systems

A parity retransmission hybrid automatic repeat request (ARQ) scheme is proposed which uses rate 1/2 convolutional codes and Viterbi decoding. A protocol is described which is capable of achieving higher throughputs than previously proposed parity retransmission schemes. The performance analysis is based on a two-state Markov model of a nonstationary channel. This model constitutes a first approximation to a nonstationary channel. The two-state channel model is used to analyze the throughput and undetected error probability of the protocol presented when the receiver has both an infinite and a finite buffer size. It is shown that the throughput improves as the …

Performability Evaluation Of Gracefully Degradable Systems, Christoph W. Lindemann

Department of Computer Science Technical Reports

No abstract provided.

Simulated Annealing On Np-Complete Problems, Russell W. Howell

ACMS Conference Proceedings 1989

The Random House Dictionary defines anneal as " ... to free (glass, metals, etc.) from internal stress by heating and gradually cooling." In the physical world, impurities are annealed out of a substance by heating it to a high temperature. As it is cooled, its molecular structure gradually settles into a stable "low-energy" configuration. It is important to cool the substance slowly, especially at lower temperatures, so that impurities do not get "frozen" into place. With careful cooling, a low-energy state can eventually be reached. This state may not be the one with the lowest potential energy, where the spins …

Strokes For Representing Univariate Vector Field Maps, David Fowler, Colin Ware

Center for Coastal and Ocean Mapping

Particle systems make an excellent tool for creating tracks (which we call strokes) in vector fields. The question addressed in this paper is how such tracks should be made to vary in size and colour in order to reveal properties such as local direction and strength of the field. We find that for strokes that vary from large to small, direction is indicated by the large end. We also find that for strokes that vary in colour, the colour of the background is the most important determinant of perceived direction.

Displaying Correlations Using Position, Motion, Point Size Or Point Colour, Serge Limoges, Colin Ware, William Knight

Center for Coastal and Ocean Mapping

An empirical study is presented which explores the use of motion, point size and grey scales for the display of statistical data; specifically, the perception of correlations between variables. The task is to measure the subject's ability to perceive differences between high correlation and low correlation for a two dimensional plot presented in different ways. One variable is always mapped to position with respect to the x axis while the other is mapped to one of six different display parameters depending on experimental condition; namely: position with respect to the y axis, frequency, phase, and amplitude of oscillation, greyscale value …

Escim: A System For The Investigation Of Meaningful Motion, Siew Hong Yang, Colin Ware

Center for Coastal and Ocean Mapping

A language is described whose purpose is the investigation of meaningful motion using Stimulus Response animation techniques. The language is capable of adjusting the shape, size and velocity of an actor in real-time computer animation. Some results are presented showing how it is possible to generate such behaviours as chasing, avoidance and hitting using this animation technique. A set of primitives are presented which we find invaluable in the control of size, stretch and velocity parameters when attempting to produce fluid and meaningful interactions.

Cascading Lzw Algorithm With Huffman Coding : A Variable To Variable Length Compression Algorithm, Ashish Khandubhai Mehta

Theses

Two common schemes in data compression are fixed to variable length coding and variable to fixed length coding. Higher compression is expected from the more flexible scheme of variable to variable length coding. In such a scheme a compression dictionary is used to transfer variable length string over the text alphabet into variable length strings over the coding alphabet. The compression is achieved due to matching longer more frequent text strings with shorter coding strings.

To obtain a variable to variable length coding we choose to cascade the LZW , variable to fixed , coding with the Huffman , fixed …

Towards A Bound For The Compression Of The Lzw Algorithm, Anoop Kumar Srivastava, Shinu Gupta

Theses

The LZW algorithm is a well known efficient adaptive compression algorithm. It is based on constructing a dictionary containing character strings from the text. A number of researchers have attempted to add variations to the original algorithm to achieve higher compression values. In this thesis we attempt to find a bound for the LZW approach. That is, we build a dictionary which gives maximum compression and satisfies prefix property of LZW algorithm.

In order to build such an optimum dictionary, the dynamic programming technique is applied. The final dictionary selected consists of entries which give maximum overall compression and also …

Supporting Value Dependency For Nested Transactions In Interbase, Ahmed K. Elmagarmid, Weimin Du

Department of Computer Science Technical Reports

No abstract provided.

Automated Translation Of Digital Logic Equations Into Optimized Vhdl Code, John Evan Stark, George Winston Zobrist

Computer Science Technical Reports

It was desired to develop an algorithm for the automated translation of finite slate machines from state table form to optimized VHDL form. To do this, algorithms arc needed for reducing the state machine to simplest form, making state assignments, producing minimal logic equations to represent the state machine, and producing VHDL code which describes the intended circuit. Various such algorithms were examined and a prototype program written to perform this translation.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, May 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

Scientific Computing In The Soviet Union, Seymour E. Goodman, William Mchenry, Peter Wolcott

Information Systems and Quantitative Analysis Faculty Publications

In the last decade, the Soviet Union has placed increased emphasis on the development of high-speed computers and networks for use in scientific, economic, and military applications. When Communist Party General Secretary Mikhail Gorbachev labeled supercomputer development a "top priority task for our science and economy" in April, 1987, he added new urgency to the production of machines that would both support activities in these applications and also serve as high-profile standard-bearers for perestroika, his program of restructuring and modernization for the nation. The Soviets have also undertaken some major projects in networking, including the creation of a nationwide packet-switched …

Constructing Trees In Parallel, Mikhail J. Atallah, S. R. Kosaraju, L. L. Larmore, G. L. Miller

Department of Computer Science Technical Reports

No abstract provided.

High Rate Concatenated Coding Systems Using Bandwidth Efficient Trellis Inner Codes, Robert H. Deng, D. J. Costello, Jr.

Research Collection School Of Computing and Information Systems

High-rate concatenated coding systems with bandwidth-efficient trellis inner codes and Reed-Solomon (RS) outer codes are investigated for application in high-speed satellite communication systems. Two concatenated coding schemes are proposed. In one the inner code is decoded with soft-decision Viterbi decoding, and the outer RS code performs error-correction-only decoding (decoding without side information). In the other the inner code is decoded with a modified Viterbi algorithm, which produces reliability information along with the decoded output. In this algorithm, path metrics are used to estimate the entire information sequence, whereas branch metrics are used to provide reliability information on the decoded sequence. …