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Computing Hough Transforms On Hypercube Multicomputers, Sanjay Ranka, Sartaj Sahni Jan 1989

Computing Hough Transforms On Hypercube Multicomputers, Sanjay Ranka, Sartaj Sahni

Electrical Engineering and Computer Science - Technical Reports

Efficient algorithms to compute the Hough transform on MIMD and SIMD hypercube multicomputers are developed. Our algorithms can compute p angles of the Hough transform of an N x N image, p ≤ N, in 0(p + log N) time on both MIMD and SIMD hypercubes. These algorithms require 0(N2) processors. We also consider the computation of the Hough transform on MIMD hypercubes with a fixed number of processors. Experimental results on an NCUBE/7 hypercube are presented.


Rottnest Island : A Reference List, Jennifer Browne Jan 1989

Rottnest Island : A Reference List, Jennifer Browne

Research outputs pre 2011

No abstract provided.


Synthesis And Study Of N-(4-Nitrobenzofurazan)-Monoaza-18-Crown-6: A Metal Sensitive Fluorophore, Shelley A. Krause Jan 1989

Synthesis And Study Of N-(4-Nitrobenzofurazan)-Monoaza-18-Crown-6: A Metal Sensitive Fluorophore, Shelley A. Krause

Dissertations

No abstract provided.


Permanganate Colorimetric Rapid Method For Chemical Oxygen Demand In Seawater, Myung Zoon Czae, Taekee Hong, Myung Hoon Kim Jan 1989

Permanganate Colorimetric Rapid Method For Chemical Oxygen Demand In Seawater, Myung Zoon Czae, Taekee Hong, Myung Hoon Kim

Chemistry & Biochemistry Faculty Publications

No abstract provided.


Iowa Geology: The Early Years, Wayne I. Anderson Jan 1989

Iowa Geology: The Early Years, Wayne I. Anderson

Journal of the Iowa Academy of Science: JIAS

In 1975 on the occasion of the first one hundred years of the Iowa Academy of Science, Robert W. Hanson summarized the history of the organization. Additional historical accounts covering many of the science disciplines were published during the centennial year. Although geology was not treated separately in these special articles, the contributions of early geologists were important to the development of science in our state. Consequently, it is appropriate to consider the contributions of early geologists in Iowa in celebration of the one hundredth annual meeting of the Iowa Academy of Science. Included in the present report are the …


Paleoenvironmental History Of The Middle Ordovician Rugosa Of Eastern North America, Gretchen Hampt Andreasen Jan 1989

Paleoenvironmental History Of The Middle Ordovician Rugosa Of Eastern North America, Gretchen Hampt Andreasen

Honors Papers

Our understanding of the structure and function of biological systems can be increased when viewed in the context of their evolutionary history on a geological time scale. Generally, both paleoecology and ecology have focused on the interrelationships of organisms and their environments in short time frames. For instance, a paleoecologist might study the fossil communities of the Columbus Limestone reefal environment at Marblehead, Ohio, or an ecologist might attempt to characterize the interrelationship of glacier lilies and their pollinators. Both workers may realize that the organisms they study evolved in response to ecological pressures, yet neither, most likely, considers that …


Expectations For Associative-Commutative Unification Speedups In A Multicomputer Environment, Ralph W. Wilkerson, Bruce M. Mcmillin Jan 1989

Expectations For Associative-Commutative Unification Speedups In A Multicomputer Environment, Ralph W. Wilkerson, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

An essential element of automated deduction systems is unification algorithms which identify general substitutions and when applied to two expressions, make them identical. However, functions which are associative and commutative, such as the usual addition and multiplication functions, often arise in term rewriting systems, program verification, the theory of abstract data types and logic programming. The introduction to the associative and commutative equality axioms together with standard unification brings with it problems of termination and unreasonably large search spaces. One way around these problems is to remove the troublesome axioms from the system and to employ a unification algorithm which …


A Definition Optimization Technique Used In A Code Translation Algorithm, David M. Dejean, George Winston Zobrist Jan 1989

A Definition Optimization Technique Used In A Code Translation Algorithm, David M. Dejean, George Winston Zobrist

Computer Science Faculty Research & Creative Works

Data flow analysis is used to optimize variable definitions in a program that translates microprocessor object code to a higher order language. © 1989, ACM. All rights reserved.


Glacial Deposits, Vol. 17, 1988-1989, Department Of Geography-Geology Jan 1989

Glacial Deposits, Vol. 17, 1988-1989, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


The Algorithm Mapper: A System For Modeling And Evaluating Parallel Applications/Archicture Pairs, C. E. Houstis, Elias N. Houstis, John R. Rice, S. M. Samartzis, D.L. Alexandrakis Jan 1989

The Algorithm Mapper: A System For Modeling And Evaluating Parallel Applications/Archicture Pairs, C. E. Houstis, Elias N. Houstis, John R. Rice, S. M. Samartzis, D.L. Alexandrakis

Department of Computer Science Technical Reports

No abstract provided.


Personal Computing For The Visually Impaired, Bruce M. Mcmillin, P. Y. Mcmillin Jan 1989

Personal Computing For The Visually Impaired, Bruce M. Mcmillin, P. Y. Mcmillin

Computer Science Faculty Research & Creative Works

The problem of providing feedback from the computer to a visually impaired user is examined. The use of traditional tactile input and output (Braille) is described. The limitations of voice output are discussed, and difficulties posed by complicated screen formats and screen review are considered.


Morning Increase In Onset Of Ischemic Stroke, John R. Marler, Thomas R. Price, Gregory L. Clark, James E. Muller, Thomas Robertson, Jay P. Mohr, Daniel B. Hìer, Philip A. Wolf, Louis R. Caplan, Mary A. Foulkes Jan 1989

Morning Increase In Onset Of Ischemic Stroke, John R. Marler, Thomas R. Price, Gregory L. Clark, James E. Muller, Thomas Robertson, Jay P. Mohr, Daniel B. Hìer, Philip A. Wolf, Louis R. Caplan, Mary A. Foulkes

Chemistry Faculty Research & Creative Works

The Time of Onset of Ischemic Stroke Was Determined for 1,167 of 1,273 Patients during the Collection of Data by Four Academic Hospital Centers between June 30, 1983, and June 30, 1986. More Strokes Occurred in Awake Patients from 10:00 Am to Noon Than during Any Other 2-Hour Interval. the Incidence of Stroke Onset Declined Steadily during the Remainder of the Day and Early Evening. the Onset of Stroke is Least Likely to Occur in the Late Evening, Before Midnight. © 1989 American Heart Association, Inc.


Safe Computing, Bruce M. Mcmillin, T. L. Casavant Jan 1989

Safe Computing, Bruce M. Mcmillin, T. L. Casavant

Computer Science Faculty Research & Creative Works

So-called worms, viruses, and Trojan horses that attack computer systems are defined. The vehicle that allows these attacks to occur, namely, the open computer internetwork, is examined. The problem of providing protection against attack in an internetwork environment is discussed. The need for professional responsibility on the part of the scientific and engineering community in enforcing strong ethical practices and neither tolerating nor condoning such practices is stressed.


Minimal Convex Extensions And Intersections Of Primary I-Ideals In F-Rings, Suzanne Larson Jan 1989

Minimal Convex Extensions And Intersections Of Primary I-Ideals In F-Rings, Suzanne Larson

Mathematics, Statistics and Data Science Faculty Works

No abstract provided.


Minimal Convex Extensions And Intersections Of Primary I-Ideals In F-Rings, Suzanne Larson Jan 1989

Minimal Convex Extensions And Intersections Of Primary I-Ideals In F-Rings, Suzanne Larson

Mathematics, Statistics and Data Science Faculty Works

No abstract provided.


Automatically Generating Functional Tests From Specifications - A Knowledge Based Constraint Logical Programming Approach, Ji Chen Jan 1989

Automatically Generating Functional Tests From Specifications - A Knowledge Based Constraint Logical Programming Approach, Ji Chen

Computer Science Theses & Dissertations

Recent experimental results indicate that functional testing is one of the most effective methods in detecting certain classes of faults. Very little work has been done in automating functional testing. This thesis research develops a method, called hierarchical partition, for automating functional testing. The key to our approach is the utilization of a pre-existing knowledge base about the domain of discourse. Several approaches to knowledge organiza­tion are discussed along with the resulting effects on the quantity and quality of functional tests produced. This research is an application and development of Generic Constraint Logic Programming and the Knowledge Driven …


Snow And Avalanche Physics: Physical Analysis Of Factors Affecting The Stability Of A Seasonal Continental Snowpack, James Frankenfield Jan 1989

Snow And Avalanche Physics: Physical Analysis Of Factors Affecting The Stability Of A Seasonal Continental Snowpack, James Frankenfield

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Each section in this paper is intended to be as independent as possible. An attempt has been made to avoid references to other sections, and in particular to equations previously used. Hopefully the reader will not find it necessary to page back and forth very much. Figures and footnotes are numbered separately for each section.

A glossary has been included to assist the reader who is unfamiliar with some of the terms used. It includes entries of a qualitative nature (e.g. 'rime', 'graupel') as well as technical terms (e.g. 'Strouhal number').

The text was prepared using Wordperfect 4.1. Certain symbols …


A Microcomputer-Based Cia System Designed To Compliment Traditional Instruction In Navy Technical Training, John M. Kaiser Jan 1989

A Microcomputer-Based Cia System Designed To Compliment Traditional Instruction In Navy Technical Training, John M. Kaiser

CCAC Theses and Dissertations

A prototype microcomputer-based CBI program was developed to provide review, structured self-study, and remediation to students undergoing initial skills training at the Naval Air Technical Training Center (NATTC), Lakehurst, NJ. The program demonstrates the capabilities of the authoring (LSAUT) and delivery (LSSTU) programs that are parts of the Language Skills Computer Aided Instruction (LSCAI) system developed by the Navy Personnel Research and Development Center and the University of Utah. A course of instruction at NATTC, Lakehurst was selected for this project on the basis of level of training, student throughput, attrition and setback rates, and category of learning objectives. Student …


Space Reactor Arms Control: Overview, Joel R. Primack, Nancy E. Abrams, Steven Aftergood, David W. Hafemeister, Daniel O. Hirsch, Robert Mozley, Oleg F. Prilutsky, Stanislav N. Rodionov, Roald Z. Sagdeev Jan 1989

Space Reactor Arms Control: Overview, Joel R. Primack, Nancy E. Abrams, Steven Aftergood, David W. Hafemeister, Daniel O. Hirsch, Robert Mozley, Oleg F. Prilutsky, Stanislav N. Rodionov, Roald Z. Sagdeev

Physics

Unshielded nuclear reactors provide the lightest and most survivable long-lived sources of electric power available to support military satellites. Restricting their use now, before a new generation of larger space reactors is tested and deployed by the US and USSR, could help prevent an arms race in space. Space nuclear power systems have been used by the United States and the Soviet Union since the 1960s. The Soviet Union has used orbiting nuclear reactors to power more than 30 radar ocean reconnaissance satellites (RORSATs). Two RORSATs have accidentally re-entered and released their radioactivity into the environment, and a third, Cosmos …


Mobile Deployable Bases And Ports: A Study For Interim Requirements, William Glenn Moore Jan 1989

Mobile Deployable Bases And Ports: A Study For Interim Requirements, William Glenn Moore

Marine Affairs Theses and Major Papers

Logistics is an age old problem that has been the key to the greatest victories and defeats in history. Maritime support of wartime land campaigns as well as conflicts at sea, has been the answer to that problem even as far back in history as the ancient Greek Empire. Throughout the ages however the lesson that seems to be learned and relearned, the hard way, is that of logistic support. Today the United States is faced with what, to some seems to be an overwhelming problem in logistic support overseas, particularly in the maritime transportation and support arena. The U.S. …


A Less-Polluted Future For Boston Harbor?: Assessing Selected Impacts Of A Citizen Information Program, Enid Carol Kumin Jan 1989

A Less-Polluted Future For Boston Harbor?: Assessing Selected Impacts Of A Citizen Information Program, Enid Carol Kumin

Marine Affairs Theses and Major Papers

The demand for good public information is a need which many environmental groups are now attempting to fill. Programs are generally designed around a particular environmental issue. One such effort is the Boston Harbor "Sewer Tour" Program run by 'Save the Harbor/Save the Bay' in Boston, Massachusetts. The Sewer Tour Program addresses matters of water pollution control in the Metropolitan Boston area. The present study examines the impact of the Sewer Tour Program on participants and spillover effects on their communities. A mailed survey is used to collect the data. A framework for data analysis is drawn from psychological research …


Socioeconomic Aspects Of Small-Scale Commercial Fisheries Development In The Republic Of The Marshall Islands, Cheryl Ann Mandich Jan 1989

Socioeconomic Aspects Of Small-Scale Commercial Fisheries Development In The Republic Of The Marshall Islands, Cheryl Ann Mandich

Marine Affairs Theses and Major Papers

This study examines the sociocultural aspects of fishery development in the Republic of the Marshall Islands. It is based upon field research conducted through interviews with indigenous fisherfolk, business people, and expatriates. The Marshall Islands were selected because they have a limited economic base, yet have abundant fishery resources which have considerable potential to generate foreign exchange. Many studies focus on the technical aspects of fishery resource development. However, none address the sociocultural factors that influence its success. This thesis demonstrates that several aspects of Marshallese fishing society, some of which correspond to characteristics of the peasantry identified by Rogers …


Antarctic Peninsula Mysticete Whales: Conservation And Research, Gregory Schofield Stone Jan 1989

Antarctic Peninsula Mysticete Whales: Conservation And Research, Gregory Schofield Stone

Marine Affairs Theses and Major Papers

This paper reports original research from two recent studies in the Antarctic Peninsula area, reviews past sighting information and policies affecting mysticete whales, and recommends future research. Due to poor management by the International Whaling Commission, mysticete whales are among the most severely depleted species groups in the Antarctic. The combined total Antarctic harvest from 1920 to 19867 for blue Balaenoptera musculus, fin B. physalus, sei B. borealis, minke B. acutorostrata and humpback Megaptera novaeangliae whales was over one million animals. The effect of this hunting pressure is the dominant factor determing the present status of Antarctic …


North Carolina Ports: A Search For Identity, Clifford S. Sharpe Jan 1989

North Carolina Ports: A Search For Identity, Clifford S. Sharpe

Marine Affairs Theses and Major Papers

North Carolina's development in colonial times and in the early stages of statehood was greatly affected by her coastline. An abundant coastline did not translate into an abundance of good ports, in fact, difficult coastal and inland navigation hampered early commercial development. North Carolina's barrier islands and numerous inlets served as a haven for pirates in colonial days, for privateers during the Revolution, and later defied the North's blockade during the Civil War. There were several attempts by individuals to encourage maritime trade in the late nineteenth and early twentieth century. Shortly after World War II the state mobilized to …


Geographical Constraints To Soviet Maritime Power, Brian Needham Jan 1989

Geographical Constraints To Soviet Maritime Power, Brian Needham

Marine Affairs Theses and Major Papers

The aim of this paper is to identify the geographical constraints to Soviet marine power, assess their impact and explore alternatives that may be considered to reduce their detrimental effects. The paper will provide a background by addressing the recent history, status and current missions of the Soviet Navy, which is the vehicle for maritime power. The nature of the geographical constraints will then be discussed before assessing individually the impacts on the four Soviet Fleets: Northern, Baltic, Black Sea, and Pacific. Finally, some alternatives will be explored to counter the vulnerability of maritime power to those geographic constraints. It …


Perceptions Of The Texas State And Federal Closures Among Inshore Shrimpers In Galveston Bay, Texas And Calcasieu Lake, Louisiana, Nina H. Garfield Jan 1989

Perceptions Of The Texas State And Federal Closures Among Inshore Shrimpers In Galveston Bay, Texas And Calcasieu Lake, Louisiana, Nina H. Garfield

Marine Affairs Theses and Major Papers

The inshore shrimp fisheries along the coast of the Gulf of Mexico represent a significant portion of the total shrimp harvest in the Gulf. The shrimp harvest is allocated to the offshore and inshore fisheries through the use of season closures. In 1981, the Gulf of Mexico Regional Fisheries Management Council began implementing a policy known as the Texas Closure; a seasonal closure of the waters of the Federal Conservation Zone concurrent with the traditional season closure of the state waters of Texas. One impact of the Texas Closure on the offshore fishery has been fleet displacement from Texas to …


Multiple-Ionization Collision Dynamics, R. (Ronald) E. Olson, J. Ullrich, H. Schmidt-Böcking Jan 1989

Multiple-Ionization Collision Dynamics, R. (Ronald) E. Olson, J. Ullrich, H. Schmidt-Böcking

Physics Faculty Research & Creative Works

The 1.4-MeV/u U32++Ne collision system is studied in detail in order to elucidate the dynamics of multiple ionization in energetic, heavy-ion atom collisions. Differential cross sections versus recoil-ion charge state, calculated by the n-body classical-trajectory Monte Carlo method, are presented for the and cphi angle dependences of the projectile, recoil ion, and ejected electrons. The calculations show a high degree of ejected-electron asymmetry towards the projectile side of the target nucleus which strongly effects the transverse-momentum balance between the heavy particles. Experimental and calculated cross sections differential in the recoil-ion charge state and transverse momentum are found to …


Strong Continuum-Continuum Couplings In The Direct Ionization Of Ar And He Atoms By 6-Mev/U U38+ And Th38+ Projectiles, D. Schneider, D. Dewitt, A. S. Schlachter, Ronald E. Olson, W. G. Graham, J. R. Mowat, R. (Robert) D. Dubois, D. H. Loyd, V. Montemayor, G. Schiwietz Jan 1989

Strong Continuum-Continuum Couplings In The Direct Ionization Of Ar And He Atoms By 6-Mev/U U38+ And Th38+ Projectiles, D. Schneider, D. Dewitt, A. S. Schlachter, Ronald E. Olson, W. G. Graham, J. R. Mowat, R. (Robert) D. Dubois, D. H. Loyd, V. Montemayor, G. Schiwietz

Physics Faculty Research & Creative Works

Doubly differential cross sections have been measured as a function of the electron energy and observation angle for electron emission following collisions of 6-MeV/u U38+ and Th38+ on He and Ar. The electron-emission data show an enhancement at forward angles and a decrease at backward angles with respect to scaled-cross-section results based on the Born approximation. Comparison with classical-trajectory Monte Carlo calculations suggests that the deviation from the Born approximation can be explained by continuum-continuum couplings. By comparing with previously published data, we found that the forward enhancement as well as the backward decrease follow a q/vp (q,vp …


The Strong Perfect Graph Conjecture For Pan-Free Graphs, Stephan Olariu Jan 1989

The Strong Perfect Graph Conjecture For Pan-Free Graphs, Stephan Olariu

Computer Science Faculty Publications

A graph G is perfect if for every induced subgraph F of G, the chromatic number χ(F) equals the largest number ω(F) of pairwise adjacent vertices in F. Berge's famous Strong Perfect Graph Conjecture asserts that a graph G is perfect if and only if neither G nor its complement G contains an odd chordless cycle of length at least five. Its resolution has eluded researchers for more than twenty years. We prove that the conjecture is true for a class of graphs which strictly contains the claw-free graphs.


The Iowa Science Teachers Fall Conference And School Science And Mathematics Association Annual Convention, 1989, Iowa Academy Of Science Jan 1989

The Iowa Science Teachers Fall Conference And School Science And Mathematics Association Annual Convention, 1989, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Map ... 3
Speakers: Sam Rhine, Bill Aldridge, Bonnie Litwiller ... 4
Sessions ... 7
Application for Membership ... Centerfold
Registration Forms ... Centerfold