Physical Sciences and Mathematics Commons^™

Optimal Control Of Delayed Differential-Algebraic Inclusions, Boris S. Mordukhovich, Lianwen Wang

Mathematics Research Reports

This paper concerns constrained dynamic optimization problems governed by delayed differential-algebraic systems. Dynamic constraints in such systems, which are particularly important for engineering applications, are described by interconnected delay-differential inclusions and algebraic equations. We pursue a two-hold goal: to study variational stability of such control systems with respect to discrete approximations and to derive necessary optimality conditions for both delayed differential-algebraic systems and their finite-difference counterparts using modern tools of variational analysis and generalized differentiation. We are not familiar with any results in these directions for differential-algebraic inclusions even in the delay-free case. In the first part of the paper …

The Approximate Maxium Principle In Constrained Optimal Control, Boris S. Mordukhovich, Ilya Shvartsman

Mathematics Research Reports

The paper concerns optimal control problems for dynamic systems governed by a parametric family of discrete approximations of control systems with continuous time. Discrete approximations play an important role in both qualitative and numerical aspects of optimal control and occupy an intermediate position between discrete-time and continuous-time control systems. The central result in optimal control of discrete approximations is the Approximate Maximum Principle (AMP), which is justified for smooth control problems with endpoint constraints under certain assumptions without imposing any convexity, in contrast to discrete systems with a fixed step. We show that these assumptions are essential for the validity …

Kernel Estimation Of Rate Function For Recurrent Event Data, Chin-Tsang Chiang, Mei-Cheng Wang, Chiung-Yu Huang

Johns Hopkins University, Dept. of Biostatistics Working Papers

Recurrent event data are largely characterized by the rate function but smoothing techniques for estimating the rate function have never been rigorously developed or studied in statistical literature. This paper considers the moment and least squares methods for estimating the rate function from recurrent event data. With an independent censoring assumption on the recurrent event process, we study statistical properties of the proposed estimators and propose bootstrap procedures for the bandwidth selection and for the approximation of confidence intervals in the estimation of the occurrence rate function. It is identified that the moment method without resmoothing via a smaller bandwidth …

Identification Of Tyr413 As An Active Site Residue In The Flavoprotein Tryptophan 2-Monooxygenase And Analysis Of Its Contribution To Catalysis, Pablo Sobrado, Paul F. Fitzpatrick

Chemistry Faculty Research & Creative Works

The flavoenzyme tryptophan 2-monooxygenase catalyzes the oxidation of tryptophan to indole acetamide, carbon dioxide, and water. The enzyme is a homologue of L-amino acid oxidase. In the structure of L-amino acid oxidase complexed with aminobenzoate, Tyr372 hydrogen bonds with the carboxylate of the inhibitor in the active site. All 10 conserved tyrosine residues in tryptophan 2-monooxygenase were mutated to phenylalanine; steady state kinetic characterization of the purified proteins identified Tyr413 as the residue homologous to Tyr372 of L-amino acid oxidase. Y413F and Y413A tryptophan 2-monooxygenase were characterized more completely with tryptophan as the substrate to probe the contribution of this …

United States Patent: Application Of High Spin Polarization Materials In Two Terminal Non-Volatile Bistable Memory Devices, Bernard Doudin, Andrei Sokolov, Cheol-Soo Yang, Lu Yuan, Sy-Hwang Liou

Sy-Hwang Liou Publications

Disclosed are two terminal bistable memory cells having least two high-spin polarization magnetic material junctions which are separated from one another by electron trap site defect containing insulator. The two terminal bistable memory cells demonstrate stable, low current readable, hysteretic resistance states which are set by the flow of a relatively high, (eg. a milliamp or less), plus or minus polarity D.C. current therethrough, which resistance is monitored by lower magnitude A.C. or D.C. current flow therethrough. Preferred cells have at least one Cr0₂/Cr₂0₃/ CrO₂ sequence but typically have multiple Cr0₂/Cr …

Analysis Of The Role Of The Active Site Residue Arg98 In The Flavoprotein Tryptophan 2-Monooxygenase, A Member Of The L-Amino Oxidase Family, Pablo Sobrado, Paul F. Fitzpatrick

Chemistry Faculty Research & Creative Works

The flavoprotein tryptophan 2-monooxygenase catalyzes the oxidative decarboxylation of tryptophan to indole acetamide. We have previously identified tryptophan 2-monooxygenase as a homologue of L-amino acid oxidase [Sobrado, P., and Fitzpatrick, P. F. (2002) Arch. Biochem. Biophys. 402, 24-30]. On the basis of the sequence comparisons of the different LAAO family members, Arg98 of tryptophan 2-monooxygenase can be identified as an active site residue which interacts with the carboxylate of the amino acid substrate. The catalytic properties of R98K and R98A tryptophan 2-monooxygenase have been characterized to evaluate the role of this residue. Mutation of Arg98 to lysine decreases the first-order …

In-Field Labeling Of Western Corn Rootworm Adults (Coleoptera: Chrysomelidae) With Rubidium, Timothy M. Nowatzki, Bradley Niimi, Kelli J. Warren, Sean Putnam, Lance J. Meinke, David C. Gosselin, F. Edwin Harvey, Thomas E. Hunt, Blair Siegfried

School of Natural Resources: Faculty Publications

Field and laboratory studies were conducted in 2000 and 2001 to determine the feasibility of mass marking western corn rootworm adults, Diabrotica virgifera virgifera LeConte, with RbCl in the field. Results showed that application of rubidium (Rb) in solution to both the soil (1 g Rb/plant) and whorl (1 g Rb/plant) of corn plants was optimal for labeling western corn rootworm adults during larval development. Development of larvae on Rb-enriched corn with this technique did not significantly influence adult dry weight or survival. Rb was also highly mobile in the plant. Application of Rb to both the soil and the …

Low Temperature (2k - 20k) Heat Capacity Determination Of A Polycrystalline Zirconium Oxide (Zro) Based Material Containing Calcium (Ca) And Europium (Eu), Watasha M. Wade

Electronic Dissertations and Theses

The calorimetric properties of a CaEuZrO based sample, synthesized by a solid-state reaction process in the Electron Transport and Magnetic Properties of Materials (ETMPM) lab, are investigated by analyzing low temperature (2 -20 K) heat capacity data. The total heat capacity of a material may be expressed as C = Celec + Cph + Cnuc + Cmag + Ci. In mathematical terms, it may be expressed as C = yT + aT3 + An T-2 + Ci. In this equation, the term yT is the electronic heat capacity, aT3 is the lattice or phonon heat capacity, AnT-2 is the nuclear …

Optimization Of Breast Cancer Screening Modalities, Yu Shen, Giovanni Parmigiani

Johns Hopkins University, Dept. of Biostatistics Working Papers

Mathematical models and decision analyses based on microsimulations have been shown to be useful in evaluating relative merits of various screening strategies in terms of cost and mortality reduction. Most investigations regarding the balance between mortality reduction and costs have focused on a single modality, mammography. A systematic evaluation of the relative expenses and projected benefit of combining clinical breast examination and mammography is not at present available. The purpose of this report is to provide methodologic details including assumptions and data used in the process of modeling for complex decision analyses, when searching for optimal breast cancer screening strategies …

Modeling The Incubation Period Of Anthrax, Ron Brookmeyer, Elizabeth Johnson, Sarah Barry

Johns Hopkins University, Dept. of Biostatistics Working Papers

Models of the incubation period of anthrax are important to public health planners because they can be used to predict the delay before outbreaks are detected, the size of an outbreak and the duration of time that persons should remain on antibiotics to prevent disease. The difficulty is that there is little direct data about the incubation period in humans. The objective of this paper is to develop and apply models for the incubation period of anthrax. Mechanistic models that account for the biology of spore clearance and germination are developed based on a competing risks formulation. The models predict …

Internal Phosphorus Loading In Spring Lake: Year 1, Dr. Alan Steinman, Dr. Rick Rediske

Scientific Technical Reports

The rate of phosphorus release from sediments, and the degree to which alum reduces phosphorus release from sediments, was investigated in Spring Lake during the summer of 2003. Triplicate cores were sampled from 4 sites in the lake, and exposed to one of four treatments in the laboratory: 1) oxygen/alum; 2) oxygen/ no alum; 3) nitrogen/alum; or 4) nitrogen/no alum. Both soluble reactive phosphorus (SRP) and total phosphorus (TP) release rates were virtually undetectable in the alum treatments (both with and without oxygen). Low, but detectable, release rates were measured in the oxygen/no alum treatment. The highest release rates were …

Normal Forms For Nonlinear Discrete Time Control Systems, Boumediene Hamzi, Issa Amadou Tall

Miscellaneous (presentations, translations, interviews, etc)

We study the feedback classification of discrete-time control systems whose linear approximation around an equilibrium is controllable. We provide a normal form for systems under investigation.

Trust, Collaboration, And Financial Return In Conservation/Development Partnerships, New England Environmental Finance Center

Economics and Finance

In early 2002 the New England Environmental Finance Center hosted a series of roundtable discussions among municipal officials, residential developers, land trust representatives, and others about "Innovative Approaches to Land Conservation and Smart Growth". Among our observations was that for many of the over 20 conservation/development partnerships we discussed in the series, creation and maintenance of trust was central to success or failure of various stages of the partnership. This suggested a link between creation of trust and financial return for traditionally opposed project partners.

To further examine this matter, we interviewed 11 round table participants and asked questions about …

Lewis And Clark And The Geology Of The Great Plains, Robert F. Diffendal Jr., Anne P. Diffendal

School of Natural Resources: Faculty Publications

Meriwether Lewis and William Clark undertook their journey with the Corps of Discovery in 1804-1806 in order to explore the area that the United States had purchased from France in 1803. Then known as Louisiana, this region included almost everything west of the Mississippi to the continental divide. In order to find the best route across the continent, President Thomas Jefferson charged Lewis with following the Missouri River to its headwaters and then locating rivers flowing down the west side of the Rocky Mountains to the Columbia River and into the Pacific Ocean. Jefferson's written instructions further specified that the …

The John Muir Newsletter, Winter 2003/2004, The John Muir Center For Environmental Studies

Muir Center Newsletters (1981-2015)

Newsletter ^ERSnY OF THE PACIFIC, STOCKTON. CA Volume 14, Number l Winter 2008-2004 John Mum and Civilization Corinne Wong, Clackamas, Oregon (Editor's note: Corinne Wong is a graduating senior double majoring in Environmental Studies and Geosciences. In addition, Wong is a student athlete in women's basketball at the University of the Pacific. This paper was prepared in the Fall of 2002 for an undergraduate course, "John Muir and the Environment.") J-ohn Muir was very much a man of nature. He was a geologist, botanist, mountaineer, nature writer, and, as most commonly recognized, a conservationist. His love for nature is a …

Deconstructing Bases: Fair, Fitting, And Fast Bases, Thomas Q. Sibley

Mathematics Faculty Publications

No abstract provided.

The Prairie Naturalist Volume 35, No.4 December 2003

The Prairie Naturalist

HOME RANGE AND MOVEMENTS OF EASTERN AND RIO GRANDE WILD TURKEY FEMALES IN NORTHEASTERN

SOUTH DAKOTA ▪ C. P. Lehman, L. D. Flake, and A. P. Leif

THE BAT FAUNA OF SOUTHEASTERN SOUTH DAKOTA . J. E. Lane, C. L. Buck, and R. M. Brigham

FIRST REPORT OF THE NORTH DAKOTA RARE BIRD COMMITTEE ▪ D. Svingen and R. E. Martin

BREEDING CHRONOLOGY OF DABBLING DUCKS IN MINNEDOSA, MANITOBA ▪ A. M. Wells and H. H. Prince

A LIVE COLLECTION OF A PISTOLGRIP FROM NEBRASKA ▪ S. C. Schainost

NEW NESTING DATES FOR SOME BREEDING BIRDS IN NORTH DAKOTA ▪ …

Case 3270: Isometrinae Clark, 1917 (Ecinodermata, Crinoidea): Proposed Emendation Of Spelling To Isometrainae To Remove Homonymy With Isometrinae Kraepelin, 1891 (Arachnida, Scorpiones), Victor Fet, Charles G. Messing

Marine & Environmental Sciences Faculty Articles

The purpose of this application, under Articles 55 and 29 of the Code, is to remove the homonymy between the crinoid subfamily name ISOMETRINAE Clark, 1917 (type genus Isometra Clark, 1908; family ANTEDONIDAE) and the scorpion subfamily name ISOMETRINAE Kraepelin, 1891 (type genus Isometrus Ehrenberg in Hemprich & Ehrenberg, 1828; family BUTHIDAE). It is proposed that the entire generic name of Isometra should be adopted as the stem, so that the correct spelling of the crinoid subfamily will become ISOMETRAINAE Clark, 1917.

Drill 3.1, Vadim Ponomarenko

Mathematics Faculty Research

Distance learning can offer a solution to a long-standing challenge of undergraduate education: how to assign an appropriate amount of work to each student, and how to assess this work efficiently. In this paper I describe the Depository of Repetitive Internet-based probLems and Lessons (DRILL), an online system for providing education and assessment for precalculus, which can substitute for routine problems given in homework and as exam questions. Its special features include:

• adaptive testing,
• on-the-fly question generation,
• instant assessment,
• context-sensitive help,
• question balancing, and
• two-dimensional test design.

Targeting Methanopterin Biosynthesis To Inhibit Methanogenesis, Razvan Dumitru, Hector Palencia, Scott D. Schroeder, Bree A. Demontigny, James M. Takacs, Madeline E. Rasche, Jess L. Miner, Stephen W. Ragsdale

James M. Takacs Publications

This paper describes the design, synthesis, and successful employment of inhibitors of 4-( β -D-ribofuranosyl) aminobenzene-5’-phosphate (RFA-P) synthase, which catalyzes the first committed step in the biosynthesis of methanopterin, to specifically halt the growth of methane-producing microbes. RFA-P synthase catalyzes the first step in the synthesis of tetrahydromethanopterin, a key cofactor required for methane formation and for one-carbon transformations in methanogens. A number of inhibitors, which are N-substituted derivatives of p-aminobenzoic acid (pABA), have been synthesized and their inhibition constants with RFA-P synthase have been determined. Based on comparisons of the inhibition constants among various inhibitors, we propose that the …

Physics Department News, December 2003, College Of Arts And Sciences

Physics Newsletter

Contents from Volume 2, Issue 2:

• A Note from the Editor
• From the Chair
• What’s New at the University
• Faculty Highlights
• Staff Highlights
• Accelerator Upgrade 5
• PhysTEC
• Distinguished Alumni Award
• Alumni News
• Recent Guest
• Goldwater Scholar
• New Grants
• Student Awards
• Recent Graduates
• Department Roster
• Photo Gallery
• Feedback/Update Reply Form

Groundwater Test Pumping In The Tambellup Townsite, Louise Hopgood

Resource management technical reports

Previous studies have concluded that the township of Tambellup is underlain by a perched aquifer. Test pumping and groundwater modelling indicated that groundwater pumping may be an effective way of protecting townsite infrastructure by lowering the water table beneath the town. This report presents results of the test pumping and provides likely bore yields, prediction of pumping influence and likely optimum production bore spacing.

Semantic (Web) Technology In Action: Ontology Driven Information Systems For Search, Integration, And Analysis, Amit P. Sheth, Cartic Ramakrishnan

Kno.e.sis Publications

Semantics is seen as the key ingredient in the next phase of the Web infrastructure as well as the next generation of information systems applications. In this context, we review some of the reservations expressed about the viability of the Semantic Web. We respond to these by identifying a Semantic Technology that supports the key capabilities also needed to realize the Semantic Web vision, namely representing, acquiring and utilizing knowledge. Given that scalability is a key challenge, we briefly review our observations from developing three classes of real world applications and corresponding technology components: search/browsing, integration, and analytics. We distinguish …

Semantic Web Processes: Semantics Enabled Annotation, Discovery, Composition, And Orchestration Of Web Scale Processes, Jorge Cardoso, Amit P. Sheth

Kno.e.sis Publications

This tutorial deals with the evolution of inter- Enterprise and Web scale process to support e-commerce and e-services. It taps into the promises of two of the hottest R&D and technology areas: Web services and the Semantic Web. It presents how applying semantics to each of the steps in the Semantic Web Process lifecycle can help address critical issues in reuse, integration and scalability.

The Translocation Of Golden Perch, Murray Cod And Australian Bass, Into And Within Western Australia, For The Purposes Of Recreational Stocking, Domestic Stocking And Commercial And Non-Commercial Aquaculture. A Discussion Paper., Department Of Fisheries

Fisheries Management Papers

This discussion paper has been prepared to provide information to assist in assessment of the possible impact of the translocation of golden perch (Macquaria ambigua), Murray cod (Maccullochella peelii peelii) and Australian bass (Macquaria novemaculeata) into and within Western Australia, for the purposes of recreational stocking, domestic stocking, commercial and non-commercial aquaculture. In assessing the translocation of any aquatic species, economic and social benefits must be balanced with biological and environmental risks.

Physica: The Newsletter Of Utep's Department Of Physics, Utep Department Of Physics

The Department of Physics

Electronic newsletter of UTEP's Department of Physics, December 2003.

A Solution To Einstein’S Field Equations For A Tachyonic Gas: Possible Astrophysical Applications, Kris H. Green, W. John Cocke

Mathematical and Computing Sciences Faculty/Staff Publications

In this paper we show that a change in the signs of some of the metric components of the solution of the field equations for the classical cosmic string results in a solution which we interpret as a time-dependent wall composed of tachyons. We show that the walls have the property of focusing the paths of particles which pass through them. As an illustration of this focusing, we demonstrate the results of a simple simulation of the interaction between one such tachyon wall and a rotating disk of point masses. This interaction leads to the temporary formation of spiral structures. …

Leaf And Wood Utilization In The Middle Missouri River, Kim Rager

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

No abstract provided.

Nectar Rewards Of Insect-Adapted Flowers In A Forest/Farm Landscape: Measurement Challenges And Ecological Questions, Theresa Bordenkecher Dailey

All-Inclusive List of Electronic Theses and Dissertations

Native forest wildflowers of the Midwestern United States forests now compete with agricultural weeds for the attention of insect pollinators. The tiny quantities of nectar secreted by these insect-pollinated flowers are measured using laboratory techniques such as colorimetry. However, these techniques are used with the tacit assumption that nectar sugar identity does not affect estimates of carbohydrate content. I tested this hypothesis using fructose, glucose, and sucrose and found that after reaction with anthrone, fructose products differed from those of other sugars in light absorbance measured by a spectrophotometer. Potential error from using an inappropriate sugar standard is greater than …

Identification Of Spatial And Temporal Patterns Of Secondary Succession Changes In Altamira, Brazil: Integrating Remote Sensing And Gis Technology, Hui Li

All-Inclusive List of Electronic Theses and Dissertations

There has been extensive use of remote sensing to study secondary succession of moist tropical forests in the Amazon Basin. However, scientists have not totally understood the dynamic processes of secondary succession of Amazon forests. A lack of consensus remains about what is the best approach for biomass estimation in the Amazon Basin using remotely sensed data. It is not clear which spectral wavelength bands have the best relationship with biomass values and what are the specific relationships between biomass and TM satellite radiance. The strategies in this research, based on analysis of detailed ground-based data and satellite TM image …