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Cascading Lzw Algorithm With Huffman Coding : A Variable To Variable Length Compression Algorithm, Ashish Khandubhai Mehta May 1989

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 …


Supporting Value Dependency For Nested Transactions In Interbase, Ahmed K. Elmagarmid, Weimin Du May 1989

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

Department of Computer Science Technical Reports

No abstract provided.


A Virtual Memory Operating System For A Distributed Workstation Environment, James Griffioen May 1989

A Virtual Memory Operating System For A Distributed Workstation Environment, James Griffioen

Department of Computer Science Technical Reports

No abstract provided.


Taylor Instability In Ryholite Lava Flows, B. A. Baum, W. B. Krantz, Jonathan H. Fink, R. E. Dickinson May 1989

Taylor Instability In Ryholite Lava Flows, B. A. Baum, W. B. Krantz, Jonathan H. Fink, R. E. Dickinson

Geology Faculty Publications and Presentations

A refined Taylor instability model is developed to describe the surface morphology of rhyolite lava flows. The effect of the downslope flow of the lava on the structures resulting from the Taylor instability mechanism is considered. Squire's (1933) transformation is developed for this flow in order to extend the results to three-dimensional modes. This permits assessing why ridges thought to arise from the Taylor instability mechanism are preferentially oriented transverse to the direction of lava flow. Measured diapir and ridge spacings for the Little and Big Glass Mountain rhyolite flows in northern California are used in conjunction with the model …


Multi-Layer Structure Of Nitrogen Adsorbed On Graphite, S. K. Wang, J. C. Newton, R. Wang, H. Taub, John R. Dennison, H. Shechter May 1989

Multi-Layer Structure Of Nitrogen Adsorbed On Graphite, S. K. Wang, J. C. Newton, R. Wang, H. Taub, John R. Dennison, H. Shechter

All Physics Faculty Publications

Elastic neutron diffraction has been used to study the structure and layering of nitrogen films adsorbed on the (002) surfaces of an exfoliated graphite substrate. The neutron-diffraction pattern of the fully compressed monolayer at a coverage Θ=1.67 layers and a temperature ≲11 K which we reported earlier has been reanalyzed (unity coverage corresponds to a complete layer having the commensurate √3 × √3 structure). We now find it to be consistent with a four-sublattice pinwheel structure as well as the two-sublattice herringbone structure which we found previously. Below 11 K, we infer crystallization of the bilayer at Θ between 2.6 …


Cultural Resource Inventory And Testing In The Salt Creek Pocket And Devils Lane Areas, Needles District, Canyonlands National Park, Utah, Betsy L. Tipps, Nancy J. Hewitt, P-Iii Associates, Inc. May 1989

Cultural Resource Inventory And Testing In The Salt Creek Pocket And Devils Lane Areas, Needles District, Canyonlands National Park, Utah, Betsy L. Tipps, Nancy J. Hewitt, P-Iii Associates, Inc.

All U.S. Government Documents (Utah Regional Depository)

This document is the final technical report on the first phase of a multiyear archeological program conducted in Canyonlands National Park. Some of the purposes of this project are to gather information for upgrading the park's interpretive program, increase the scientific understanding of Canyonlands' prehistory, and prepare a research design to guide future investigation. Archeological inventory of 4500 acres in the Needles District revealed a previously undocumented Archaic occupation and showed that Formative peoples using the area were primarily the Mesa Verde Anasazi, not the Fremont and Anasazi as previously thought. The data also indicate that prehistoric peoples used the …


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

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.


Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection May 1989

Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection

Publications (WR)

In September 1987 the Nevada Division of Environmental Protection revised Water Quality Standards for Las Vegas Wash (LVW) and Lake Mead. Standards were set for chlorophyll-a and unionized ammonia in Las Vegas Bay (LVB) (NDEP 1987). The 1986 and 1987 LVB data showed non-achievement of both the chlorophyll-a and unionized ammonia standard which triggered an analysis of total phosphorus and total ammonia Total Maximum Daily Loads and Waste Load Allocations which are presented in this report. This report is separated into three sections: 1. 1987 Las Vegas Bay Water Quality Conditions and Seasonal Periodicity. 2. Concentration Estimates at Northshore Road …


Scientific Computing In The Soviet Union, Seymour E. Goodman, William Mchenry, Peter Wolcott May 1989

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 May 1989

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.


Soil Temperature Influence On Water Use And Yield Under Variable Irrigation, Jon M. Wraith May 1989

Soil Temperature Influence On Water Use And Yield Under Variable Irrigation, Jon M. Wraith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The need for efficient use of water resources has increased the importance of optimum soil water usage in agricultural systems. Soil temperature has been shown to be important in influencing the early development of many plant species. Many agricultural regions have suboptimal soil temperature regimes for plant growth, and some cultural practices have been shown to reduce near-surface soil temperatures. The seasonal influence of soil temperature on soil water extraction and aboveground and belowground plant growth under variable irrigation was investigated at the USU Greenville Farm in Logan, UT. Soil surface mulches and buried heat cables were used to modify …


The Geology And Structural Significance Of The Arch Mountain Area, Northern Black Mountains, Mohave County, Arizona, Edward Eschner May 1989

The Geology And Structural Significance Of The Arch Mountain Area, Northern Black Mountains, Mohave County, Arizona, Edward Eschner

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Arch Mountain area of northwestern Mohave County, Arizona, is typified by rocks that range from Precambrian to Quatemary in age. Arch mountain is a north-trending horst bounded on the west by the Petroglyph Wash graben and on the east by the Virgin Basin. A low-angle normal fault, herein named the Arch Mountain detachment fault, is exposed for 6 km along strike just below the ridge crest of Arch Mountain, and it is typified by a 2-20 cm thick zone of hematite-impregnated breccia and cataclasite. The detachment fault places an upper plate of Precambrian gneiss, Paleozoic quartzite, shale and dolomite, …


Probability Of Discrete Failures, Weibull Distribution, Mary Jo Hansen May 1989

Probability Of Discrete Failures, Weibull Distribution, Mary Jo Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The intent of this research and these is to describe the development of a series of charts and tables that provide the individual and cumulative probabilities of failure applying to the Weibull statistical distribution. The mathematical relationships are developed and the computer programs are described for deterministic and Monte Carlo models that compute and verify the results. Charts and tables reflecting the probabilities of failure for a selected set of parameters of the Weibull distribution functions are provided.


Using Computer Imaging To Assess Visual Impacts Of Forest Insect And Disease Pests, Daniel Rabin May 1989

Using Computer Imaging To Assess Visual Impacts Of Forest Insect And Disease Pests, Daniel Rabin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Forest insect and disease pests alter the appearance of trees, thereby impacting visual resources. Because of the complexity of most forest landscapes, the degree of visual impact of pest-infested forest stands is difficult to quantify.

This paper describes a method of measuring visual impacts of pest-infested forest stands. Photographs of healthy Ponderosa pine trees were entered into a computer video-image-processing system. Using this system, images of trees were altered to simulate different degrees of infestation by limb rust, a forest pathogen.

The altered and unaltered images were shown to groups of observers who rated the scenes in terms of "scenic …


Management, Foraging Behavior, Diet Composition And Forage Quality Of Free-Ranging But Herded Camels In Ceeldheer District, Central Somalia, Ahmed A. Elmi May 1989

Management, Foraging Behavior, Diet Composition And Forage Quality Of Free-Ranging But Herded Camels In Ceeldheer District, Central Somalia, Ahmed A. Elmi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In Somalia, camel (Camelus dromedarius) survivability and milk production has been higher than for other domestic livestock and contributes substantially to the subsistence of Somali pastoralists. The objective of this research was to study management, foraging behavior and nutrition of camels in their natural habitat to determine how production continues under seasonal nutritional stress.

Management systems of Ceeldheer pastoralists are based on available natural pasture and water. The natural rotation grazing system maintained an ecological equilibrium in the District.

Pastoralists manipulate their herds to suit existing environmental conditions, family needs and labor availability for herding. In herd management, …


Shake-Off Measurements Of Electron-Ion-Scattering Phase Shifts, J. Greg Story, William E. Cooke May 1989

Shake-Off Measurements Of Electron-Ion-Scattering Phase Shifts, J. Greg Story, William E. Cooke

Physics Faculty Research & Creative Works

Continuum electrons are produced in a specific l state with high-energy resolution using shake-off photoionization. This process is well characterized, so that the photoionization signal is an accurate measurement of the difference between the continuum electrons wave-function phase and that produced by a hydrogenic interaction. Measurements are reported showing the phase of a Ba++e- in a d wave, in cases where it is well behaved, and in cases where doubly excited resonances produce rapid phase variations.


High Rate Concatenated Coding Systems Using Bandwidth Efficient Trellis Inner Codes, Robert H. Deng, D. J. Costello, Jr. May 1989

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. …


Towards Computable Stability Criteria For Some Multidimensional Stochastic Processes Arising In Queueing Models, Wojciech Szpankowski Apr 1989

Towards Computable Stability Criteria For Some Multidimensional Stochastic Processes Arising In Queueing Models, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.


Santa Clara Magazine, Volume 31 Number 3, Spring 1989, Santa Clara University Apr 1989

Santa Clara Magazine, Volume 31 Number 3, Spring 1989, Santa Clara University

Santa Clara Magazine

10 - VISION Santa Clara's new president talks about his priorities for the University in the decade ahead.

15 - FAMILY IN CRISIS Is the Silicon Valley family an endangered species?

18 - DUBLIN: CITY OF 1,000 YEARS Today it is a bustling European capital. But progress has come at a price.

22 - GEORGE AND THE SILVER FOX A behind-the-scenes look at President and Mrs. Bush.

27 - WHO SHALL CARE .. . AND HOW? By 2020 every fourth American may be 65 or over.


Chromospherically Active Stars. Vii. 39 Ceti=Ay Ceti, Hd185151=V1764 Cygni, And Binary Synchronization, Francis C. Fekel, Joseph J. Eitter Apr 1989

Chromospherically Active Stars. Vii. 39 Ceti=Ay Ceti, Hd185151=V1764 Cygni, And Binary Synchronization, Francis C. Fekel, Joseph J. Eitter

Information Systems and Engineering Management Research Publications

Improved orbital elements have been determined for 39 Ceti and HD 185151.39 Cet has a circular orbit with an orbital period of 56.82 days, which differs substantially from its rotational period of 75-78 days. An observation of the lithium region of 39 Cet shows that the G5 III component has almost no lithium in its outer atmosphere. HD 185151 has a circular orbit with an orbital period of 40.142 days and has a nearly identical rotational period. The large mass function suggests that the secondary is a late A to mid F type star whose continuum should be visible at …


Water Current, Volume 21, April 1989 Apr 1989

Water Current, Volume 21, April 1989

Water Current Newsletter

US Water Institutes/Centers Celebrate 25th Anniversary
United Kingdom Geophysicist Now Head of UNL Geololgy Department
Future Depends on Water Quality and Quantity
NItrate Area Map "May Be Out in June"
Large Savings with Nitrogen Best Management Practices
Sandhills Voices Heard at Conference
Papio-Missouri River NRD Receives Progress Award
Pioneer Irrigation Award Goes to Former NPPD Administrator
Research Hydrologist is Kremer Lecturer
Public-Private Sectors Join in National Celebration
Nebraska Unicameral Considers Water Legislation Bills in First Unicameral Session


Habitat Use And Diet Analysis Of Breeding Common Barn Owls In Western Nebraska, Joseph A. Gubanyi M.S. Apr 1989

Habitat Use And Diet Analysis Of Breeding Common Barn Owls In Western Nebraska, Joseph A. Gubanyi M.S.

School of Natural Resources: Dissertations, Theses, and Student Research

I studied barn owl (Tyto alba) breeding biology in western Nebraska 1984-1986. I had greatest success capturing males (56% success) at night using trap doors at nest sites and females (91 % success) using hoop nets at nest sites during the day. Barn owls removed 16 of 23 tail-mounted radios. Eight birds were radio-tracked for 7-14.5 hours. The mean foraging range was 198 ha (32- 299 ha, n = 8) with < 1 % overlap among birds from adjacent nest sites. Field-tested telemetry error was high (mean displacements of radio-locations for 2 birds were 208 and 241 m). I found no relationship between percent cover in foraging habitat and reproductive success. I identified 10,140 prey items from 15 nest sites and found both annual and seasonal variation in barn owl diets. Microtus ochrogaster occurred most frequently (32.7%) and increased in the diet from 17.6 to 27.2 to 43.5% 1984-1986. M. ochrogaster and Perognathus hispidus annual frequencies were …


The State Of Tampa Bay- 1988, Tampa Bay Regional Planning Council (Tbrpc), Agency On Bay Management Apr 1989

The State Of Tampa Bay- 1988, Tampa Bay Regional Planning Council (Tbrpc), Agency On Bay Management

Reports

Council's Agency on Bay Management has continued to lead and support major Bay related activities through legislation, development review, intergovernmental coordination, impact assessment and public education in 1988. Management and research efforts expand for the Bay as awareness grows of its significance. The State of the Bay - 1988 document represents the compilation of regional activities and these expanding effort to promote the Tampa Bay estuary.


Photodissociation Of Co In The Thermosphere Of Venus, Jane L. Fox Apr 1989

Photodissociation Of Co In The Thermosphere Of Venus, Jane L. Fox

Physics Faculty Publications

Recent investigations of CO photoabsorption demonstrate that photodissociation longward of the ionization threshold at 88.5 nm occurs primarily through line absorptions rather than continuous processes. We have constructed high resolution photoabsorption cross sections for CO at rotational temperatures near 250 K from the improved data on dissociating transitions. We examine the effects of the new cross sections on the rate of solar photodissociation of CO in the thermosphere of Venus and compare the results to values obtained with the lower resolution cross sections available previously. We find that the photodissociation profile peaks slightly higher in the atmosphere and the peak …


Electron-Electron Interactions In Transfer And Excitation In F⁸⁺ →₂ Collisions, Michael Schulz, J. P. Giese, J. K. Swenson, Sheldon Datz, Peter F. Dittner, Herbert F. Krause, Harald Schone, Charles Randy Vane, Malika Benhenni, Stephen M. Shafroth Apr 1989

Electron-Electron Interactions In Transfer And Excitation In F⁸⁺ →₂ Collisions, Michael Schulz, J. P. Giese, J. K. Swenson, Sheldon Datz, Peter F. Dittner, Herbert F. Krause, Harald Schone, Charles Randy Vane, Malika Benhenni, Stephen M. Shafroth

Physics Faculty Research & Creative Works

We have measured projectile Auger electrons emitted after collisions of H-like F with H2. The cross sections for emission of KLL, KLM, KLN, and KLO Auger electrons show maxima as a function of the projectile energy. One maximum in the KLL emission cross section is due to resonant transfer and excitation. A second maximum in the cross section for KLL emission as well as the maxima in the emission cross section for the higher-n Auger electrons are attributed to a new transfer and excitation process. This involves excitation of a projectile electron by one target electron accompanied by …


The Style Of Late Cenozoic Deformation At The Eastern Front Of The California Coast Ranges, Carl M. Wentworth, Mark D. Zoback Apr 1989

The Style Of Late Cenozoic Deformation At The Eastern Front Of The California Coast Ranges, Carl M. Wentworth, Mark D. Zoback

United States Geological Survey: Staff Publications

The 1983 Coalinga earthquake occurred at the eastern boundary of the California Coast Ranges in response to northeast directed thrusting. Such movements over the past 2 Ma have produced Coalinga anticline by folding above the blind eastern tip of the Coalinga thrust zone. The 600-km length of the Coast Ranges boundary shares a common structural setting that involves westward upturn of Cenozoic and Cretaceou strata at the eastern front of the Coast Ranges and a major, southwest facing step in the basement surface beneath the western Great Valley. Like Coalinga anticline, Pliocene and Quaternary folding and faulting along the rest …


Approximate Delay Analysis Of Transaction Oriented Communication In A Distributed System, Dan C. Marinescu Mar 1989

Approximate Delay Analysis Of Transaction Oriented Communication In A Distributed System, Dan C. Marinescu

Department of Computer Science Technical Reports

No abstract provided.


Benchmarking Of Mimd Hardware On Subdomain Splitting Elliptic Pde Solvers., Elias N. Houstis, John R. Rice, E. A. Vavalis Mar 1989

Benchmarking Of Mimd Hardware On Subdomain Splitting Elliptic Pde Solvers., Elias N. Houstis, John R. Rice, E. A. Vavalis

Department of Computer Science Technical Reports

No abstract provided.


Certain Stability Type And Integrable Two-Dimensional Hamiltonian Systems, Foek T. Hioe Mar 1989

Certain Stability Type And Integrable Two-Dimensional Hamiltonian Systems, Foek T. Hioe

Physics Faculty/Staff Publications

We present the results of applying an analytical method, using a new concept involving a periodic stability around a line of initial values, to two Hamiltonian systems with two degrees of freedom each with several parameters. By requiring the systems to have this type of stability, we have been led to known integrable cases for the systems. For one of the systems, our analysis gives six other cases, two of which turn out to be nonintegrable. The status of the remaining four cases has not been established.


The Nature Of Parallel Programming, Per Brinch Hansen Mar 1989

The Nature Of Parallel Programming, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

Parallel programming is the art of writing programs for computers that perform many operations simultaneously. This essay discusses the nature of parallel programming without going into technical details. It uses a sorting problem to illustrate what it means to solve a problem in parallel, how we write parallel programs, how parallel computers execute them, and how fast they run. The author expects that scientific users of parallel computers may find ease of programming more important than maximum performance. He suggests ways to make this possible.