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Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth Jan 1993

Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth

All Peer-Reviewed Publications

Trypanosoma (Nannomonas) congolense comprises morphologically identical but genetically heterogeneous parasites infective to livestock and other mammalian hosts; three different genotypes of this parasite have been described previously. Restriction enzyme fragment length polymorphisms (RFLPs) in both kinetoplast DNA minicircle and nuclear DNA sequences, and randomly amplified polymorphic deoxyribonucleic acid (RAPD) patterns have been used here to demonstrate the existence of another type of T. (N.) congolense that is genotypically distinct from those that have so far been characterized at the molecular level. A highly repetitive, tandemly arranged DNA sequence and oligonucleotide primers, for use in polymerase chain reaction (PCR) amplification are …


Optimal Greedy Algorithms For Indifference Graphs, Peter J. Looges, Stephan Olariu Jan 1993

Optimal Greedy Algorithms For Indifference Graphs, Peter J. Looges, Stephan Olariu

Computer Science Faculty Publications

A fundamental problem in social sciences and management is understanding and predicting decisions made by individuals, various groups, or the society as a whole. In this context, one important concept is the notion of indifference. We characterize the class of indifference graphs, that is, graphs which arise in the process of quantifying indifference relations. In particular, we show that these graphs are characterized by the existence of a special ordering of their vertices. As it turns out, this ordering leads naturally to optimal greedy algorithms for a number of computational problems, including coloring, finding a shortest path between two vertices, …


When Will A Genetic Algorithm Outperform Hill-Climbing?, Melanie Mitchell, John H. Holland Jan 1993

When Will A Genetic Algorithm Outperform Hill-Climbing?, Melanie Mitchell, John H. Holland

Computer Science Faculty Publications and Presentations

In this paper we review some previously published experimental results in which a simple hillclimbing algorithm-Random Mutation Hill-Climbing (RMHC)-significantly outperforms a genetic algorithm on a simple "Royal Road" function. vVe present an analysis of RMHC followed by an analysis of an "idealized" genetic algorithm (IGA) that is in turn significantly faster than RMHC. We isolate the features of the IGA that allow for this speedup, and discuss how these features can be incorporated into a real GA and a fitness landscape, making the GA better approximate the IGA. We use these features to design a modified version of the previously …


Aminolysis Of Activated Esters Of Indole-3-Acetic Acid In Acetonitrile, Michael J. Pfeiffer, Samir B. Hanna Jan 1993

Aminolysis Of Activated Esters Of Indole-3-Acetic Acid In Acetonitrile, Michael J. Pfeiffer, Samir B. Hanna

Chemistry Faculty Research & Creative Works

Seven activated esters of indole-3-acetic acid (IAA) [4-oxo-l,2,3-benzotriazin-3-yl indole-3-acetate (IAA-3HBO), succinimido indole-3-acetate (IAA-NHS), 5-norbornene-1,3-dicarboximido indole-3-acetate (IAA-NHND), phthalimido indole-3-acetate (IAA-NHP), naphthalimido indole-3-acetate (IAA-NHN), 4-nitrophenyl indole-3-acetate (IAA-4NP), 8-quinolyl indole-3-acetate (IAA-8HQ)] were prepared and characterized. Their kinetics of aminolysis with butylamine, piperidine, and pyrrolidine in acetonitrile were investigated. In general, the observed pseudo-first-order rate constants, kobs, fit the two-term rate equation kobs = k1[amine] + k2[amine]2. For the aminolysis of six of the esters with piperidine there was no measurable k2 term. The 8-hydroxyquinoline ester and N-hydroxy-naphthalimide ester of indole-3-acetic acid had no measurable k2 term for aminolysis with either pyrrolidine or piperidine. …


Computational Neural Networks In Chemistry: Model Free Mapping Devices For Predicting Chemical Reactivity From Molecular Structure, David Wayne Elrod Dec 1992

Computational Neural Networks In Chemistry: Model Free Mapping Devices For Predicting Chemical Reactivity From Molecular Structure, David Wayne Elrod

Dissertations

Computational neural networks (CNNs) are a computational paradigm inspired by the brain’s massively parallel network of highly interconnected neurons. The power of computational neural networks derives not so much from their ability to model the brain as from their ability to learn by example and to map highly complex, nonlinear functions, without the need to explicitly specify the functional relationship. Two central questions about CNNs were investigated in the context of predicting chemical reactions: (1) the mapping properties of neural networks and (2) the representation of chemical information for use in CNNs.

Chemical reactivity is here considered an example of …


A Case Tool For Conceptual Database Design, Keng Siau, Kok Phuang Tan, Hock Chuan Chan Dec 1992

A Case Tool For Conceptual Database Design, Keng Siau, Kok Phuang Tan, Hock Chuan Chan

Research Collection School Of Computing and Information Systems

The paper describes a Computer Aided Software Engineering (CASE) tool to support conceptual database modelling. One popular approach for conceptual database modelling is use of the Entity-Relationship (ER) model. The paper proposes the use of an Enhanced Entity-Relationship (EER) model for conceptual database modelling. This Enhanced Entity-Relationship model extends the Entity-Relationship model by incorporating the generalization/specialization, aggregation and categorization abstractions. The CASE tool, which is based on the Enhanced Entity-Relationship model, is known as the Enhanced Entity-Relationship Diagrammer (EERD). In addition, the CASE tool supports direct visual query and update based on the EERM.


An Enhanced User Interface For The Saber Wargame, Donald R. Moore Dec 1992

An Enhanced User Interface For The Saber Wargame, Donald R. Moore

Theses and Dissertations

This thesis is part of an on-going effort by the Air Force Institute of Technology to develop a computer-based, theater-level wargame for the Air Force Wargaming Center at Maxwell AFB, AL. The wargame, Saber, is intended to augment the education the students receive at the Air War College and the Air Command and Staff College in the employment of air and ground power. This thesis documents the integrated design and implementation of the two components of the Saber user interface: the pre-processor and the post-processor. Although previous thesis students designed and implemented substantial portions of the user interface, a fully …


Face Recognition With Neural Networks, Dennis L. Krepp Dec 1992

Face Recognition With Neural Networks, Dennis L. Krepp

Theses and Dissertations

This study investigated neural networks for face verification and classification. The research concentrated on developing a neural network based feature extractor and/or classifier to perform authorized user verification in a realistic work environment. Recognition accuracy, system assumptions, training time, and execution time were analyzed to determine the feasibility of a neural network approach. Data was collected using a camcorder and two segmentation schemes: manual segmentation and motion-based, automatic segmentation. Data consisted of over 2000. 32x32 pixel, 8 bit gray scale images of 52 subjects; each subject had two to ten days worth of images collected. Several training and test sets …


Real Image Visual Display System, James R. Brandt Dec 1992

Real Image Visual Display System, James R. Brandt

Theses and Dissertations

This thesis investigates a technique for improving the perception of three-dimensionality in images generated by a Silicon Graphics workstation. The technique involves using a spherical mirror into which the graphics from the CRT are projected. A real image of the graphic is formed by the mirror and it appears to be floating at the image plane. The three-dimensional effect is improved by adding reflections or shadows of the displayed object. Additionally, a method of using real objects with computer generated shadows and computer generated objects with real shadows is investigated. This is done in an effort to quantify how far …


Domain Analysis Within The Gensif Framework, Heiko Thimm Oct 1992

Domain Analysis Within The Gensif Framework, Heiko Thimm

Theses

The GenSIF framework which is targeted towards very large, distributed, and complex software systems recently has been proposed to accomplish a form of systems engineering and systems development in which the issue of systems integration is considered from the beginning on.

One of the components of GenSIF is domain analysis. Domain analysis leads to the design of a domain model. The specific needs GenSIF has in that area were investigated with an emphasis on domain modeling. Main points addressed in that investigation were the issue regarding the relevant information for the domain modeling process and the required type of domain …


Student Fact Book, Fall 1992, Wright State University, Office Of Student Information Systems, Wright State University Oct 1992

Student Fact Book, Fall 1992, Wright State University, Office Of Student Information Systems, Wright State University

Wright State University Student Fact Books

The student fact book has general demographic information on all students enrolled at Wright State University for Fall Quarter, 1992.


Santa Clara Magazine, Volume 35 Number 1, Fall 1992, Santa Clara University Oct 1992

Santa Clara Magazine, Volume 35 Number 1, Fall 1992, Santa Clara University

Santa Clara Magazine

11 - SENIOR SEMINAR Elderhostel brings a different kind of student to Santa Clara. By Christine Spielberger '69

14 - DAYS RICH WITH EMPTINESS A noted Catholic writer reflects on his annual retreat to a Trappist abbey, a respite from the daily stress of getting and spending. In a related article, he discusses "The Inner Experience," an unpublished book by Thomas Merton that examines the modern contemplative lifestyle. By Mitch Finley '73

22 - WHAT'S WRONG WITH THIS PICTURE? The image of an all -male Senate committee weighing the merits of Anita Hill 's charges against Clarence Thomas spurred a …


On Correspondence, Line Tokens And Missing Tokens, Chia-Hoang Lee, Anupam Joshi Oct 1992

On Correspondence, Line Tokens And Missing Tokens, Chia-Hoang Lee, Anupam Joshi

Department of Computer Science Technical Reports

No abstract provided.


Backpropagation Learns Marr's Operator, Anupam Joshi, Chia-Hoang Lee Sep 1992

Backpropagation Learns Marr's Operator, Anupam Joshi, Chia-Hoang Lee

Department of Computer Science Technical Reports

No abstract provided.


An Analysis Of Product Metrics In Terms Of Qualitative And Formal Metric Properties, Tuliz Dengi, George Zobrist Sep 1992

An Analysis Of Product Metrics In Terms Of Qualitative And Formal Metric Properties, Tuliz Dengi, George Zobrist

Computer Science Technical Reports

In recent years, the increased concern for developing reliable, cost-efficient software systems has been accompanied by a higher need to analyze and measure software complexity. Numerous metrics have been proposed to measure software complexity and functionality. Yet, testing the validity of these metrics has been a difficult and long process. As an initial test of metric validity, some researchers have suggested the use of formal metric properties so that metrics without a sound theoretical base are rejected right away. This approach has the additional advantage of allowing a reasonable and fair comparison of software metrics.

In this study, a discussion …


The Calendar - September 1992, Nova University Sep 1992

The Calendar - September 1992, Nova University

The Calendar

No abstract provided.


Examination Of Psychological Type And Preferred Negotiation Tactics And Strategies Of Contract Negotiators, John P. Hebert, Alan J. Meade Sep 1992

Examination Of Psychological Type And Preferred Negotiation Tactics And Strategies Of Contract Negotiators, John P. Hebert, Alan J. Meade

Theses and Dissertations

This research identified the psychological types of government and industry contract negotiators and determined whether their preference for using negotiation tactics and strategies were correlated with their respective psychological types. A survey consisting of the Myers-Briggs Type Indicator (MBTI) and a questionnaire concerning use of negotiation tactics and strategies was mailed to 2,000 contracting professionals of the National Contract Management Association (NCMA). During May and June 1992, 627 usable surveys were received. The MBTI results were paired with the responses to the negotiation tactics and strategies questionnaire. These results were analyzed on a microcomputer using the DBase IV, Excel, and …


Testing The Role Of Technical Information In Public Risk Perception, Branden B. Johnson, Peter M. Sandman, Paul Miller Sep 1992

Testing The Role Of Technical Information In Public Risk Perception, Branden B. Johnson, Peter M. Sandman, Paul Miller

RISK: Health, Safety & Environment (1990-2002)

It is widely believed that more detail about health effects and likely exposure routes is apt to reduce citizens' concerns about low-probability Risks. The authors' study suggests that providing such detail may not be as useful as, e.g., addressing public concerns and keeping citizens current on officials' actions.


Santa Clara Magazine, Volume 34 Number 4, Summer 1992, Santa Clara University Jul 1992

Santa Clara Magazine, Volume 34 Number 4, Summer 1992, Santa Clara University

Santa Clara Magazine

12 - SQUEEZING THE MIDDLE CLASS Gone, in the face of staggering recessionary losses, is the peace of mind that once seemed the virtual birthright of the middle class. By Elizabeth Fernandez '79

18 - A FRAGILE PEACE El Salvador shows a ravaged but hopeful face to a delegation from SCU, Stanford, and the Diocese of San Jose. By Thomas Shanks, S.J.

24 - IT TAKES TEAMWORK Facing fierce global competition, more and more U.S. companies are exploring work teams. By Lisa Agrimonti '87

28 - GIVING TO SANTA CLARA: IT RUNS IN THE FAMILY A tradition of giving and …


Ccis Networking - July 1992, Nova University Jul 1992

Ccis Networking - July 1992, Nova University

CCIS Networking / SCIS Networking magazines

No abstract provided.


Ua3/8/1 John Robinson Professorship Report, Wku Ogden College Of Science & Technology Jun 1992

Ua3/8/1 John Robinson Professorship Report, Wku Ogden College Of Science & Technology

WKU Administration Documents

Report by Dr. John Riley, John Robinson Professor of activities for 1987-1992 funded by Ogden Foundation.


Prediction Of Paper Color: A Process Simulation Approach, Mayank Chaturvedi Jun 1992

Prediction Of Paper Color: A Process Simulation Approach, Mayank Chaturvedi

Masters Theses

A simulation model was developed for a dye mixing process and for the prediction of the optical properties of the paper. The model was integrated with the MAPPS (Modular Analysis of Pulp and Paper Systems) simulation software package. The model was validated using dyed handsheets made in a laboratory and dyed paper made on a pilot papermachine. Validation comprised of prediction of the optical properties of the handsheets and the machine-made paper which contained various combinations of three non-fluorescent dyes. Sheet reflectances were predicted at 20 nanometer intervals for discrete light wavelength range of 400 to 700 nanometers and verified …


Review: 'Optical Fiber Communications' (2nd Edition), By Gerd Keiser, Bradley D. Duncan May 1992

Review: 'Optical Fiber Communications' (2nd Edition), By Gerd Keiser, Bradley D. Duncan

Electro-Optics and Photonics Faculty Publications

If first impressions are worth anything (and they usually are), I would have to admit that my first impression of the second edition of Gerd Keiser's now popular text Optical Fiber Communications was quite good. My compliments are hereby extended to the publisher for choosing a rather handsome cover and dust jacket. It stands in strong contrast to the text's first edition, which still ranks as probably the ugliest book I own, with color choices ranging from dull cream and "baby" blue to pale pink! I am now happy to say that this older version has been discretely·retired to the …


Disconjugacy And Oscillation Theory Of Linear Differential And Difference Equations, Yuhua Xu May 1992

Disconjugacy And Oscillation Theory Of Linear Differential And Difference Equations, Yuhua Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation is both a literature survey and a presentation of new and independent results.

The survey gives an overview of disconjugacy and oscillation theory for linear differential and difference equations with an emphasis on comparing the theory of difference equations to the theory of differential equations. Second order scalar equations, higher order scalar equations, matrix equations (systems) and Hamiltonian systems are discussed. A chapter on three-term recurrences of systems is also included. Both similarities and differences between differential and difference equations are described.

The new and independent results are for Hamiltonian systems of difference equations. Those results include the …


The Annual Meeting Of The Iowa Academy Of Science April 24-25, 1992 [Program, 104th Meeting], Iowa Academy Of Science Apr 1992

The Annual Meeting Of The Iowa Academy Of Science April 24-25, 1992 [Program, 104th 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
Symposia Programs --- 14
Poster Session --- 16
Campus Map --- Centerfold
Section Programs --- 18
Agricultural Sciences --- 18
Anthropology --- 20
Botany --- 21
Cellular & Molecular Biology --- 22
Chemical Education --- 26
Chemistry, Inorganic --- 26
Chemistry, Organic --- 27
Conservation --- 29
Earth Science Teaching --- 30
Elementary Science Teaching --- 30
Engineering --- 32
Geology --- 34
Linguistics --- 35
Nursing --- 36
Physics --- 37
Physiology --- 39
Psychology --- 40
Science …


Program Abstracts, 104th Session, Iowa Academy Of Science, April 24-25, 1992, Iowa Academy Of Science Apr 1992

Program Abstracts, 104th Session, Iowa Academy Of Science, April 24-25, 1992, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


Mathematical References In Literature, John S. Lew Apr 1992

Mathematical References In Literature, John S. Lew

Humanistic Mathematics Network Journal

No abstract provided.


Epistemological Pluralism: Styles And Voices Within The Computer Culture, Sherry Turkle, Seymour Papert Apr 1992

Epistemological Pluralism: Styles And Voices Within The Computer Culture, Sherry Turkle, Seymour Papert

Humanistic Mathematics Network Journal

No abstract provided.


Mathematics From An English Major's Point Of View, Elizabeth Miller, Kathleen M. Shannon Apr 1992

Mathematics From An English Major's Point Of View, Elizabeth Miller, Kathleen M. Shannon

Humanistic Mathematics Network Journal

No abstract provided.


A Survey Of Computer Use In Occupational Therapy Fieldwork Sites, Martha E. Parks Apr 1992

A Survey Of Computer Use In Occupational Therapy Fieldwork Sites, Martha E. Parks

Masters Theses

Eighty-three Western Michigan University occupational therapy fieldwork sites were surveyed to determine: (a) extent of computer use, (b) diagnostic categories with which computers are used, (c) extent of computer knowledge of registered occupational therapists (OTRs), and (d) adequacy of computer knowledge of fieldwork students. Forty-seven (56.6%) of the 83 surveys were returned. OTRs at 36 (76.6%) of the 47 sites currently use computers. Word processing is the most common way in which these OTRs use computers. The most common clinical use of computers is perceptual/motor assessment and treatment, while the most common research use of computers is for report writing. …