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The Annual Meeting Of The Iowa Academy Of Science April 20-21, 1990 [Program, 102nd Meeting], Iowa Academy Of Science Apr 1990

The Annual Meeting Of The Iowa Academy Of Science April 20-21, 1990 [Program, 102nd Meeting], Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Program Summary --- 5
General Session Speakers --- 9
Awards --- 12
Distinguished Fellow --- 12
Distinguished Service --- 13, 14
Symposia Programs --- 15
Poster Session --- 17
Campus Map --- Centerfold
Section Programs --- 22
Agricultural Sciences --- 22
Anthropology --- 25
Botany --- 26
Cellular & Molecular Biology --- 28
Chemistry, Inorganic --- 30
Chemistry, Organic --- 34
Conservation --- 37
Earth Science Teaching --- 39
Elementary Science Teaching --- 40
Engineering --- 42
Geology --- 47
Linguistics --- 48
Nursing --- 49
Physics --- 50
Physiology --- 53
Psychology --- 54
Science Teaching --- 56 …


Geology, Volcanology, And Petrology Of Cerro Bravo, A Young, Dactic, Stratovolcano In West-Central Colombia, David Tondl Lescinsky Apr 1990

Geology, Volcanology, And Petrology Of Cerro Bravo, A Young, Dactic, Stratovolcano In West-Central Colombia, David Tondl Lescinsky

LSU Historical Dissertations and Theses

The northernmost active Andean volcano, Cerro Bravo is a small, young, and very explosive stratovolcano. Cerro Bravo has produced voluminous tephra deposits, that are found> 30 km away, as well as, pumice flow deposits, block and ash flow deposits, and high-aspect lava flows, which are found proximally to the volcano. There have been eight episodes of activity during the past 6250±110 years (Herd, 1982), with the most recent <200 years ago and the present being a period of quiescence with no visible activity or thermal manifestations. Stratigraphic relationships suggest the occurrence of an initial explosive phase and a concluding effusive phase of activity during individual episodes. The products of volcanic activity at Cerro Bravo are a chemically and mineralogically monotonous suite of medium-K dacite and high-silica andesite (59.2- 67.5% SiO2 pumices and lavas. The dominant phenocrysts present are plagioclase and hornblende (oxyhomblende in lavas) with lesser quantities of orthopyroxene, titanomagnetite, and rare augite and biotite also present. Petrology and eruption dynamics …


Adaptability Experiments In The Raid Distributed Database System, Bharat Bhargava, Karl Friesen, Abdelsalam Helal, John Riedl Apr 1990

Adaptability Experiments In The Raid Distributed Database System, Bharat Bhargava, Karl Friesen, Abdelsalam Helal, John Riedl

Department of Computer Science Technical Reports

No abstract provided.


Regional Climate Centers: New Institutions For Climate Service And Climate- Impact Research, Stanley A. Changnon, Peter J. Lamb, Kenneth G. Hubbard Apr 1990

Regional Climate Centers: New Institutions For Climate Service And Climate- Impact Research, Stanley A. Changnon, Peter J. Lamb, Kenneth G. Hubbard

School of Natural Resources: Faculty Publications

In response to the need climate services at the local, state, and regional levels, a national network of regional climate centers has developed. This provides the background to this development, and outlines the functions of the centers and identifies their benefits and beneficiaries. The centers are a source of climate expertise and maintain multifaceted interfaces with the public and private sectors. Each center a) performs services, including the management of the basic data for its region and the delivery of specialized products; b) conducts applied climate studies, including the monitoring of anomalous conditions and the promotin of regional research; and …


A Proof For A Quickhull Algorithm, Jonathan Scott Greenfield, Apr 1990

A Proof For A Quickhull Algorithm, Jonathan Scott Greenfield,

Electrical Engineering and Computer Science - Technical Reports

The planar convex hull problem is fundamental to computational geometry and has many applications, including pattern recognition and image processing. QuickHull is a simple planar convex hull algorithm analogous to Hoare’s QuickSort [1]. This paper presents a pedagogical description and analysis of a QuickHull algorithm, along with a formal proof of correctness.


Santa Clara Magazine, Volume 32 Number 3, Spring 1990, Santa Clara University Apr 1990

Santa Clara Magazine, Volume 32 Number 3, Spring 1990, Santa Clara University

Santa Clara Magazine

10- SERVICE: THE ULTIMATE STRATEGY A restaurant executive reveals his formula for business success: A Satisfied Customer, Guaranteed. By Timothy W. Firnstahl '65

16 - BLENDED FAMILIES By the year 2000, there will be more stepfamilies than any other kind of family. By Peggy Hernandez '78

20 - NORTHERN IRELAND: A REPORTER'S NOTEBOOK The war between the Catholics and the Protestants is 20 years old and there is no peace in sight. By Kevin Kelly '83

24 - THE FUNERAL OF MICHAEL-JO O'MALLEY A Santa Clara Jesuit writes about a unique ritual he witnessed last summer in County Mayo, Ireland. …


Water Current, Volume 22, April 1990 Apr 1990

Water Current, Volume 22, April 1990

Water Current Newsletter

Environmental Studies Part of Geography Department, Jeanne Kay
Twentieth Annual Earth Day Observed April 22
NATO Advanced Research Workshop to be Held at UNL in September
First Irrigation Day Held February 22
Just Give Us a Call for Water Seminar Proceedings
Festival Highlights Importance of Nebraska's Groundwater
Prevention Key to Pollution
Assessment Atlas Now Available
Water Conference Council Awards
Agency Cooperation Urged at Water Conference
90s Exciting Times in Water Resources
Nebraska Counties Included in High Plains Irrigation Research
Mid-Nebraska Water Quality Demo Project Combines State and Federal Agencies to Research Irrigation Efficiency
Irrigation Bolsters Nebraska's Economy
First Nebraska Instream …


Energy Deposition Of Energetic Silicon Atoms Within A Silicon Lattice, P. Zecher, D. Wang, J. Rapaport, C. Jeff Martoff, Betty A. Young Apr 1990

Energy Deposition Of Energetic Silicon Atoms Within A Silicon Lattice, P. Zecher, D. Wang, J. Rapaport, C. Jeff Martoff, Betty A. Young

Physics

The energy dependence of the ionization produced in silicon by recoiling silicon atoms was measured in the 4–54-keV energy interval. It is found that the fraction of the recoil energy that is dissipated as ionization follows an E1/2 dependence which agrees well with the predictions of the theory of Lindhard et al. [Mat. Fys. Medd. 33, 10 (1963)].


Michigan Apple Pest Identifier And Manager Expert System, James R. Schalk Apr 1990

Michigan Apple Pest Identifier And Manager Expert System, James R. Schalk

Masters Theses

The Michigan Apple Pest Identifier and Management System (MAPI) is a knowledge- based consultation software system. MAPI was designed to provide the user with the ability to identify insects which may harm the apples of Michigan orchards and to project occurrences of maximum adult emergence. A discussion of standard entomological and expert system concepts and the application of these concepts to the processing of information by the Michigan Apple Pest Identifier and Management System is presented. Future possible expansions of the system are suggested.


Water Resources Review - April 1990, Annis Water Resources Institute Apr 1990

Water Resources Review - April 1990, Annis Water Resources Institute

AWRI Reviews

No abstract provided.


The Mapping Of A Colored Petri Net Model To An Ops5 Rule-Based Production System, Sally S. Lockwitz Apr 1990

The Mapping Of A Colored Petri Net Model To An Ops5 Rule-Based Production System, Sally S. Lockwitz

Masters Theses

This paper defines a method by which the colored petri net model of a concurrent system may be mapped to an equivalent rule-based production system. The mapping method defined is an intuitive process which results in a production system that clearly represents the petri net model.

In order to demonstrate the effectiveness and correctness of this method, the colored petri net representation of a part of a flexible manufacturing system of the Renault Car Company is mapped to an equivalent Sierra OPS5 rule-based production system.

An overview of petri nets and rule-based production systems is presented, along with a brief …


The Effect Of Tracking Network Configuration On Gps Baseline Estimates For The Casa Uno Experiment, S. Kornreich Wolf, Timothy H. Dixon, J. T. Freymuller Apr 1990

The Effect Of Tracking Network Configuration On Gps Baseline Estimates For The Casa Uno Experiment, S. Kornreich Wolf, Timothy H. Dixon, J. T. Freymuller

School of Geosciences Faculty and Staff Publications

Geodetic monitoring of subduction of the Nazca and Cocos plates is a goal of the CASA (Central and South America) Global Positioning System (GPS) experiments, and requires measurement of intersite distances (baselines) in excess of 500 km. The major error source in these measurements is the uncertainty in the position of the GPS satellites at the time of observation. A key aspect of the first CASA experiment, CASA Uno, was the initiation of a global network of tracking stations to minimize these errors. We studied the effect of using various subsets of this global tracking network on long (>100 …


Diagnostics Software For Concurrent Processing Computer Systems, Robert L. Jones Iii Apr 1990

Diagnostics Software For Concurrent Processing Computer Systems, Robert L. Jones Iii

Electrical & Computer Engineering Theses & Dissertations

Diagnostics software for analyzing ATAMM based concurrent processing systems is presented in this thesis. ATAMM (Algorithm to Architecture Mapping Model) is a new model developed by researchers at Old Dominion University and the NASA-Langley Research Center. ATAMM is capable of modeling the execution of large grain algorithms on distributed data flow architectures. Investigating a real or simulated ATAMM based system requires the aid of software tools. The software tool presented in this thesis can evaluate the behavior and performance of an ATAMM based system. The tool graphically portrays algorithm activities and processor activities. The tool's measurement capabilities indicate computing speed, …


A Comparison Of Metals In Several Ahermatypic Corals And Surficial Sediments: Mobile Pinnacles And Hoffa Reef, Northcentral Gulf Of Mexico, Kathryn M. Conko Apr 1990

A Comparison Of Metals In Several Ahermatypic Corals And Surficial Sediments: Mobile Pinnacles And Hoffa Reef, Northcentral Gulf Of Mexico, Kathryn M. Conko

OES Theses and Dissertations

Metal concentrations in marine sediment and carbonate secreting invertebrates are representative of surrounding environmental chemistry. Aluminum, Ba Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, and Zn were measured in carbonate and terrigenous phases of the $<$63 um fraction of sediment samples from two locations in the northcentral Gulf of Mexico. Enrichment factors indicate that Al, Ba, Cu, Cr, Mg, Mn, and Ni are all slightly depleted in these sediments relative to crustal abundances. Discriminant function analyses shows that the concentrations of five elements differ between locations.

Ahermatypic coral (106 specimens) from five genera collected from the study sites were analyzed for Cd, Cu, Cr, Pb, Zn, Mn, Sr, Ba, Fe, Ca and Mg. Eight elements vary between some genera, Al and Ba also vary in concentration in corals between either location. All elements except Sr are significantly depleted in the coral with respect to Ca in the …


The Fat-Pyramid: A Robust Network For Parallel Computation, Ronald I. Greenberg Apr 1990

The Fat-Pyramid: A Robust Network For Parallel Computation, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

This paper shows that a fat-pyramid of area Theta(A) built from processors of size lg A requires only O(lg^2 A) slowdown in bit-times to simulate any network of area A under very general conditions. Specifically, there is no restriction on processor size (amount of attached memory) or number of processors in the competing network, nor is the assumption of unit wire delay required. This paper also derives upper bounds on the slowdown required by a fat-pyramid to simulate a network of larger area in the case of unit wire delay.


Maintaining Quasi Serializability In Hddbss, Weimin Du, Ahmed K. Elmagarmid, Won Kim Mar 1990

Maintaining Quasi Serializability In Hddbss, Weimin Du, Ahmed K. Elmagarmid, Won Kim

Department of Computer Science Technical Reports

No abstract provided.


Critical Issues In Multidatabase Systems, Ahmed K. Elmagarmid, Marek Rusinkiewicz Mar 1990

Critical Issues In Multidatabase Systems, Ahmed K. Elmagarmid, Marek Rusinkiewicz

Department of Computer Science Technical Reports

No abstract provided.


A Multidatabase Transaction Model For Interbase, Ahmed Elmagarmid, Y. Leu, W. Litwin, Marek Rusinkiewicz Mar 1990

A Multidatabase Transaction Model For Interbase, Ahmed Elmagarmid, Y. Leu, W. Litwin, Marek Rusinkiewicz

Department of Computer Science Technical Reports

No abstract provided.


Hybrid Value/Event Representation Of Replicated Objects, Bharat Bhargava, Shirley Browne Mar 1990

Hybrid Value/Event Representation Of Replicated Objects, Bharat Bhargava, Shirley Browne

Department of Computer Science Technical Reports

No abstract provided.


A Fast O(K) Multicast Message Routing Algorithm, Thomas J. Sager, Bruce M. Mcmillin Mar 1990

A Fast O(K) Multicast Message Routing Algorithm, Thomas J. Sager, Bruce M. Mcmillin

Computer Science Technical Reports

In many multicomputer applications is it necessary for one node to send an identical message to many nodes. One to many communications are called multicasts. Although broadcasts (one to all) and unicasts (one to one) have been widely implemented, multicasts, in spite of their importance to efficient use of multicomputer systems, have not received much attention.

Minimal traffic multicasting is equivalent to the minimal Steiner tree problem and is known to be NP-complete. Therefore, a heuristic polynomial time approximation must be used; but, to take advantage of advances in second generation multicomputer hardware such as wormhole routing, a distributed multicast …


The Second International Conference On Expert Systems For Numerical Computing, John R. Rice, Robert Vichnevetsky, Elias N. Houstis Mar 1990

The Second International Conference On Expert Systems For Numerical Computing, John R. Rice, Robert Vichnevetsky, Elias N. Houstis

Department of Computer Science Technical Reports

No abstract provided.


Its A Fact! Its A Phact!, Harlan R. Shuhler Mar 1990

Its A Fact! Its A Phact!, Harlan R. Shuhler

Vertebrate Pest Conference Proceedings: 14th (1990)

To reduce the costs of providing development assistance in agriculture to the people in the Developing Countries, an international "Post-Harvest Agriculture Computer Teleconference" has been available now for more than 15 months. Suitably supplemented with electronic computer communications networks and their E-mail, these tools allow relatively inexpensive assistance. This combination offers many advantages to the organizations offering assistance and those needing help.


Bird Control On Containment Pond Sites, Lee R. Martin, Sam Hagar Mar 1990

Bird Control On Containment Pond Sites, Lee R. Martin, Sam Hagar

Vertebrate Pest Conference Proceedings: 14th (1990)

Bird deaths resulting from toxic materials in containment ponds are causing authorities to insist that action be taken to eliminate this hazard to avian wildlife. Bird control at containment pond sites is achieved by two well-known but poorly understood aversion techniques: hazing systems (sound/visual) and stretch wire. The limiting condition of either approach is that resident birds rapidly habituate while some migrating species are totally unaffected. Consequently, one must be able to accept degrees of control with an understanding of the behavior of the species involved. Birdproofing is achieved by covering an entire pond with bird net. This presentation discusses …


Development, Use, And Benefits Of The Animal Damage Control Management Information System, Darlene G. Blaney Mar 1990

Development, Use, And Benefits Of The Animal Damage Control Management Information System, Darlene G. Blaney

Vertebrate Pest Conference Proceedings: 14th (1990)

The United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Animal Damage Control (ADC) Management Information System (MIS) is in the process of being updated to a relational database format on an IBM-compatible microcomputer. The background of the MIS, the development process, the information that is collected, how the information is used by program managers, and the cost benefits of the automated system are addressed.


Mythology Of Vertebrate Pest Control, William D. Fitzwater Mar 1990

Mythology Of Vertebrate Pest Control, William D. Fitzwater

Vertebrate Pest Conference Proceedings: 14th (1990)

Controlling vertebrate species obnoxious or even dangerous to them has been a concern of the human species through the evolutionary process. Early measures were often based on religious, superstitious, and biologic fantasies. While modern control measures are better biologically founded, there still remains an aura of mythology around many accepted by the public today. Examples are given of some of them: toxicants, electromagnetics, ultrasonics, and repellents for deer, moles, and raccoons.


Required Use Of Protective Bait Stations In The U. S., William W. Jacobs Mar 1990

Required Use Of Protective Bait Stations In The U. S., William W. Jacobs

Vertebrate Pest Conference Proceedings: 14th (1990)

Beginning in the 1960s, labels for federally registered commensal rodenticides have been required to bear a statement to the effect that the baits are to be contained in "tamper-proof bait boxes" when used in locations accessible to children and nontarget animals. Faced with ample evidence of noncompliance with the letter and spirit of this portion of the label, the U. S. Environmental Protection Agency (EPA) issued a policy statement (PR Notice 83-5) and scheduled public hearings on matters pertaining to bait stations and nontarget exposure incidents involving rodenticides. EPA's findings indicate that, while some clarifications of its policies might be …


Effects Of Field Vertebrate Pest Control On Nontarget Wildlife (With Emphasis On Bird And Rodent Control), E.E. Littrell Mar 1990

Effects Of Field Vertebrate Pest Control On Nontarget Wildlife (With Emphasis On Bird And Rodent Control), E.E. Littrell

Vertebrate Pest Conference Proceedings: 14th (1990)

Vertebrate pest control measures may have an impact on nontarget wildlife. Bird and rodent control programs using avicides and rodenticides in California have been, and are currently being, examined by the California Department of Fish and Game on a routine basis. Each pesticide used has its deleterious side effects. This paper reviews these side effects and suggests possible future impacts which could be expected.


Keynote Address--Thoughts On The Future Of Vertebrate Pest Management, Russell F. Reidinger Jr. Mar 1990

Keynote Address--Thoughts On The Future Of Vertebrate Pest Management, Russell F. Reidinger Jr.

Vertebrate Pest Conference Proceedings: 14th (1990)


I greatly appreciated the invitation to attend this Conference, and to share some thoughts on the future of vertebrate pest management in the form of a Keynote Address.


In making the presentation, I will dwell mostly on a single document. This document is entitled “Strategic Plan for Animal Damage Control,” and became available in December 1989, from the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS).

The document is one of the products from a strategic planning process that began in APHIS about 2 years ago, and continues today. The process began at the highest level of …


The Human Element In Wildlife Damage Situations, Ron J. Johnson Mar 1990

The Human Element In Wildlife Damage Situations, Ron J. Johnson

Vertebrate Pest Conference Proceedings: 14th (1990)

The field of prevention and control of wildlife damage is changing and evolving along with clientele needs, pressures from user and non-user groups, and other factors. A theoretical overview of the field may offer an action model regarding changing trends and potential responses. I propose that three things happen every time a wildlife damage problem occurs: 1) A human activity, desire, or need is interfered with, 2) the experience fosters an opinion about a wild animal - usually negative, and 3) a decision is made to tolerate the situation or to control it. If control is selected, availability and effectiveness …


Rabies Control For Urban Foxes, Skunks, And Raccoons, Richard C. Rosatte, Michael J. Power, Charles D. Macinnes, Kenneth F. Lawson Mar 1990

Rabies Control For Urban Foxes, Skunks, And Raccoons, Richard C. Rosatte, Michael J. Power, Charles D. Macinnes, Kenneth F. Lawson

Vertebrate Pest Conference Proceedings: 14th (1990)

Rabies is currently enzootic in many cities of southern Ontario. The Ministry of Natural Resources is utilizing two different tactics for the control of rabies in urban wildlife rabies vectors-oral immunization with baits (foxes) and vaccination by injection following live-capture (skunks and raccoons). Between 47 and 79% of the skunks and 61 and 76% of the raccoons were captured and vaccinated (Imrab) in a 60-km2 urban area of Metropolitan Toronto during 1987, 1989. Only three cases of rabies in skunks have been reported since control began in 1987. Population increases of 120% for skunks and 40% for raccoons were noted …