Physical Sciences and Mathematics Commons^™

A Case Study Of The 8 March 1999 Freezing Rain Event For North Platte, Nebraska, Shari Mutchler

United States Department of Commerce: Staff Publications

During the morning hours of 8 March 1999, freezing precipitation fell over portions of western Nebraska, including the communities of McCook, North Platte and Valentine between midnight and 10:00 A.M. CST. The freezing precipitation resulted in dangerous travel conditions, causing several automobile accidents, along with the delay and temporary closing of area public schools 8 March 1999. The freezing rain changed over to snow later the same morning.
A forecast for snow, rather than freezing precipitation, was issued by the local forecast office. The forecast issued was based predominately on numerical weather prediction guidance, and the observed temperature profile of …

Integrals Of Periodic Functions, Sean F. Ellermeyer, David G. Robinson

Faculty and Research Publications

Computing integrals of powers of the sine function is a standard exercise in calculus. The authors show that the first integral is representative of the integral of any periodic function.

Direct Imaging Of Human Swi/Snf-Remodeled Mono- And Polynucleosomes By Atomic Force Microscopy Employing Carbon Nanotube Tips, Gavin R. Schnitzler, Chin Li Cheung, Jason H. Hafner, Andrew J. Saurin, Robert E. Kingston, Charles M. Lieber

Barry Chin Li Cheung Publications

Chromatin-remodeling complexes alter chromatin structure to facilitate, or in some cases repress, gene expression. Recent studies have suggested two potential pathways by which such regulation might occur. In the first, the remodeling complex repositions nucleosomes along DNA to open or occlude regulatory sites. In the second, the remodeling complex creates an altered dimeric form of the nucleosome that has altered accessibility to transcription factors. The extent of translational repositioning, the structure of the remodeled dimer, and the presence of dimers on remodeled polynucleosomes have been difficult to gauge by biochemical assays. To address these questions, ultrahigh-resolution carbon nanotube tip atomic …

A Local Inversion Principle Of The Nash-Moser Type, Alfonso Castro, J. W. Neuberger

All HMC Faculty Publications and Research

We prove an inverse function theorem of the Nash-Moser type. The main difference between our method and that of [J. Moser, Proc. Nat. Acad. Sci. USA, 47 (1961), pp. 1824-1831] is that we use continuous steepest descent while Moser uses a combination of Newton-type iterations and approximate inverses. We bypass the loss of derivatives problem by working on finite dimensional subspaces of infinitely differentiable functions.

Automated Online News Classification With Personalization, Chee-Hong Chan, Aixin Sun, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Classification of online news, in the past, has often been done manually. In our proposed Categorizor system, we have experimented an automated approach to classify online news using the Support Vector Machine (SVM). SVM has been shown to deliver good classification results when ample training documents are given. In our research, we have applied SVM to personalized classification of online news.

Fast Implementation Of Depth Contours Using Topological Sweep, Kim Miller, Suneeta Ramaswami, Peter Rousseeuw, Toni Sellarès, Diane Souvaine, Ileana Streinu, Anja Struyf

Computer Science: Faculty Publications

The concept of location depth was introduced in statistics as a way to extend the univariate notion of ranking to a bivariate configuration of data points. It has been used successfully for robust estimation, hypothesis testing, and graphical display. These reguire the computation of depth regions, which form a collection of nested polygons. The center of the deepest region is called the Tukey median. The only available implemented algorithms for the depth contours and the Tukey median are slow, which limits their usefulness. In this paper we describe an optimal algorithm which computes all depth contours in &Ogr;(n 2) time …

Risk Mapping For Northern Kenya And Southern Ethiopia, D. Layne Coppock

Environment and Society Faculty Publications

We used results from 120 group interviews collected in 1998 to quantify how inhabitants across northern Kenya and southern Ethiopia perceive and rank various risks to their livelihoods. We also mapped risk patterns using Global Positioning System (GPS) coordinates. Respondents recognized 15 sources of risk overall, with the most common being reliable access to food and water. Other risks were not mentioned by a majority of respondents and reflected diversity in local situations. Country of residence, wealth class, gender, and predominant means of food production (pastoralism, agro-pastoralism, and farming) influenced risk ranking. For example, wealthy males were most concerned about …

Prediction Of The Crystal Structures Of Perovskites Using The Software Program Spuds, Michael W. Lufaso, Patrick M. Woodward

Chemistry Faculty Research and Scholarship

The software program SPuDS has been developed to predict the crystal structures of perovskites, including those distorted by tilting of the octahedra. The user inputs the composition and SPuDS calculates the optimal structure in ten different Glazer tilt systems. This is performed by distorting the structure to minimize the global instability index, while maintaining rigid octahedra. The location of the A-site cation is chosen so as to maximize the symmetry of its coordination environment. In its current form SPuDS can handle up to four different A-site cations in the same structure, but only one octahedral ion. Structures predicted …

Electronic-Structure Modifications Induced By Surface Segregation In La0.65Pb0.35Mno3 Thin Films, C.N. Borca, B. Xu, T. Komesu, H.-K. Jeong, M.T. Liu, Sy_Hwang Liou, Shane Stadler, Y. Idzerda, Peter A. Dowben

Sy-Hwang Liou Publications

Using spin-polarized inverse photoemission and X-ray absorption spectroscopy techniques, we show that the electronic structure of La_0.65Pb_0.35MnO₃ thin films depends on the composition at the surface. With a gentle annealing procedure, the surface provides a maximum of 80% spin asymmetry at 0.5 eV above the Fermi level in spite of extensive Pb segregation. A heavily annealed (restructured) surface exhibits a reduced surface "ordering" temperature of 240 K (compared to the approximately 335 K bulk value) as well as a reduced spin asymmetry value of 40% at 0.5 eV above Fermi energy.

Dual Heuristic Programming For Fuzzy Control, George G. Lendaris, Thaddeus T. Shannon, Larry J. Schultz, Steven Hutsell, Alec Rogers

Systems Science Faculty Publications and Presentations

Overview material for the Special Session (Tuning Fuzzy Controllers Using Adaptive Critic Based Approximate Dynamic Programming) is provided. The Dual Heuristic Programming (DHP) method of Approximate Dynamic Programming is described and used to the design a fuzzy control system. DHP and related techniques have been developed in the neurocontrol context but can be equally productive when used with fuzzy controllers or neuro-fuzzy hybrids. This technique is demonstrated by designing a temperature controller for a simple water bath system. In this example, we take advantage of the TSK model framework to initialize the tunable parameters of our plant model with reasonable …

Tracking The Fate Of A High Concentration Groundwater Nitrate Plume Through A Fringing Marsh: A Combined Groundwater Tracer And In Situ Isotope Enrichment Study, Cr Tobias, Sa Macko, Iris C. Anderson, Elizabeth A. Canuel, Jw Harvey

VIMS Articles

A groundwater plume enriched in (15)NO(3)(-) was created upgradient of a mesohaline salt marsh. By measuring the changes in concentration and isotopic enrichment of NO(3)(-), N(2)O, N(2), NH(4)(+), and particulate organic nitrogen (PON) during plume transport through the marsh, in situ rates of dissimilatory nitrate reduction to ammonium (DNRA) and denitrification (DNF) were estimated, as well as N storage in the reduced N pools. For groundwater discharge within the top 10 cm of marsh, NO(3)(-) removal was 90% complete within the 50 cm of marsh nearest the upland border. The peak NO(3)(-) loss rate from the plume ranged from 208 …

Semiclassical Scattering Of An Electric Dipole Source Inside A Spherical Particle, James A. Lock

Physics Faculty Publications

Semiclassical scattering phenomena appearing in the far-zone scattered intensity of a point source of electromagnetic radiation inside a spherical particle are examined in the context of both ray theory and wave theory, and the evolution of the phenomena is studied as a function of source position. A number of semiclassical effects that do not occur for plane-wave scattering by the sphere appear prominently for scattering by an interior source. These include a series of scattering resonances and a new family of rainbows in regions of otherwise total internal reflection. Diffractive effects accompanying the semiclassical phenomena are also examined. (C) 2001 …

Existence Of Solutions Of The Classical Yang-Baxter Equation For A Real Lie Algebra, Jorg Feldvoss

University Faculty and Staff Publications

We characterize finite-dimensional Lie algebras over the real numbers for which the classical Yang-Baxter equation has a non-trivial skew-symmetric solution (resp. a non-trivial solution with invariant symmetric part). Equivalently, we obtain a characterization of those finite-dimensional real Lie algebras which admit a non-trivial (quasi-) triangular Lie bialgebra structure.

Meeting Medical Terminology Needs: The Ontology-Enhanced Medical Concept Mapper, Gondy Leroy, Hsinchun Chen

CGU Faculty Publications and Research

This paper describes the development and testing of the Medical Concept Mapper, a tool designed to facilitate access to online medical information sources by providing users with appropriate medical search terms for their personal queries. Our system is valuable for patients whose knowledge of medical vocabularies is inadequate to find the desired information, and for medical experts who search for information outside their field of expertise. The Medical Concept Mapper maps synonyms and semantically related concepts to a user's query. The system is unique because it integrates our natural language processing tool, i.e., the Arizona (AZ) Noun Phraser, with human-created …

Meeting Medical Terminology Needs: The Ontology-Enhanced Medical Concept Mapper, Gondy Leroy, Hsinchun Chen

CGU Faculty Publications and Research

This paper describes the development and testing of the Medical Concept Mapper, a tool designed to facilitate access to online medical information sources by providing users with appropriate medical search terms for their personal queries. Our system is valuable for patients whose knowledge of medical vocabularies is inadequate to find the desired information, and for medical experts who search for information outside their field of expertise. The Medical Concept Mapper maps synonyms and semantically related concepts to a user's query. The system is unique because it integrates our natural language processing tool, i.e., the Arizona (AZ) Noun Phraser, with human-created …

Influence Of Early Lithification On Late Diagenesis Of Microbialities: Insights From Δ 18O Composition Of Upper Cambrian Carbonate Deposits From The Southern Appalachians, B. Glumac

Geosciences: Faculty Publications

This paper documents a difference in isotopic compositions between Upper Cambrian microbial and non-microbial micritic deposits and proposes implications for diagenesis of calcimicrobial deposits. The δ 18O values (-10.98 to -8.71; average -9.88‰ VPDB) of calcimicrite comprising shallow subtidal microbialites from the southern Appalachians are more negative than: (1) the calcimicrite from associated subtidal non-microbial deposits (-8.98 to -7.16; average -7.82), suggesting a different diagenetic history; and (2) estimates of Late Cambrian marine calcite values (-5 to -3 ‰), indicating postdepositional modifications. Early diagenetic calcification of microbial deposits promoted the formation of growth cavities and borings rimmed with marine fibrous …

Three Dimensional Hydrodynamic Modeling Study, Craney Island Eastward Expansion, Lower James River And Elizabeth River, Virginia, Harry V. Wang, S. C. Kim, John D. Boon, A. Y. Kuo, G. M. Sisson, J. M. Brubaker, J. P-Y. Maa

Reports

The Craney Island Eastward Expansion Hydrodynamic Model Study was conducted in three phases: 1) model calibration and verification for the Elizabeth River, 2) model testing of four Craney Island expansion options using single variable runs (using a single variable, tidal range, for model input), 3) model testing of two expansion options using historical runs (using multiple variables in real time for model input). The expansion option designs were evaluated for both global and local hydrodynamic change through simulation comparisons with the Base Case condition.

Effect Of Rare Locally Ordered Regions On A Disordered Itinerant Quantum Antiferromagnet With Cubic Anisotropy, Rajesh S. Narayanan, Thomas Vojta

Physics Faculty Research & Creative Works

We study the quantum phase transition of an itinerant antiferromagnet with cubic anisotropy in the presence of quenched disorder, paying particular attention to the locally ordered spatial regions that form in the Griffiths region. We derive an effective action where these rare regions are described in terms of static annealed disorder. A one-loop renormalization-group analysis of the effective action shows that for order-parameter dimensions p<4, the rare regions destroy the conventional critical behavior, and the renormalized disorder flows to infinity. For order-parameter dimensions p>4, the critical behavior is not influenced by the rare regions; it is described by the conventional dirty cubic fixed point. We also discuss the influence of the rare regions on the fluctuation-driven first-order transition …

The Prairie Naturalist Volume 33, No.4 December 2001

The Prairie Naturalist

SPECIES, SEASON, AND DENSITY OF BURIED SEEDS SURVIVING FOX SQUIRREL DEPREDATION ▪ C. C. Smith, and J. M. Briggs

RELATI0NSHIP OF HYDROLOGICAL CONDITIONS AND POPULATlONS OF BREEDING PIPING PLOVERS ▪ D. S. Licht,

DEMODICOSIS IN A WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS) IN SOUTH DAKOTA ▪ C. N. Jacques, J. A Jenks. M. B. Hildreth. R. J. Schauer, and D. D. Johnson

SURVEYS OF CALLING AMPHIBIANS IN NORTH DAKOTA ▪ D. H. Johnson, and R. D. Batie

EFFECTS OF HUMAN PRESENCE ON VOCALIZATIONS OF GRASSLAND BIRDS IN KANSAS ▪ S. L Bye, R. J. Robel, and K. E. Kemp

Reviewers 2001

Author …

Helping At-Risk Students Add Up: Motivational Lessons For Students In High School Mathematics, Karen Beckner

Mahurin Honors College Capstone Experience/Thesis Projects

No abstract provided.

Ecological Characterization Of Stormwater Detention Ponds In Virginia's Coastal Plain, Rebecca Jo Thomas, Carl H. Hershner

Reports

No abstract provided.

Groundwater Study Of The Wongan Hills Townsite, M Deshon

Resource management technical reports

A groundwater study was carried out in the townsite of Wongan Hills, Western Australia. It aimed to accelerate the implementation of effective salinity management options. The study consisted of a drilling investigation, installation of a piezometer network, a pumping test, groundwater flow modelling and a flood risk analysis.

Groundwater Study Of The Koorda Townsite, Louise Hopgood

Resource management technical reports

A groundwater study was carried out in the townsite of Koorda. It aimed to accelerate the implementation of effective salinity risk management. The study consisted of a drilling investigation and expansion of a piezometer network, a pumping test, groundwater flow modelling and a flood risk analysis.

Lort And Young Rivers Catchment : Catchment Appraisal 2001, Jamie Bowyer, Esperance Catchment Support Team (Wa)

Resource management technical reports

Using the Rapid Catchment Appraisal process, this report summarises current information for the Lort and Young Rivers Catchment, 75 kilometres west of Esperance in Western Australia. The Rapid Catchment Appraisal (RCA) process is one of the processes included in the strategy to tackle salinity and its management in Western Australia. The RCA process provides a 'snap shot' of information on the risk and impact to agricultural production and natural resources within regional geographic catchments.

Yarra Yarra Catchment : Rapid Catchment Appraisal Report 2001, M Clarke

Resource management technical reports

Using the Rapid Catchment Appraisal process, this report summarises current information for the Yarra Yarra Catchment, Northern Agricultural Region in Western Australia. The Rapid Catchment Appraisal (RCA) process is one of the processes included in the strategy to tackle salinity and its management in Western Australia. The RCA process provides a 'snap shot' of information on the risk and impact to agricultural production and natural resources within regional geographic catchments.

Vegetation Health Analysis (Peel-Harvey Coastal Plain Catchment) : An Impact Study On The Use Of Alkaloam (Bauxite Residue) As A Soil Amendment On Agricultural Land, Garry Heady, Chris Ferreira

All other publications

In 1997, a program was established to monitor the long term, (a minimum of 10 years), impacts on remnant native vegetation, of Alkaloam bauxite residue used as a soil amendment on adjacent agricultural land Data collection is to be repeated on an annual basis for the duration of the program. This report presents pre-treatment site and vegetation data for 2001, the fourth year of sampling in the program. Overall results are compared with those from 1997, 1998 and 2000. Descriptions of monitoring sites and an outline of project design and methodology are provided so the report can be read independently …

Groundwater Study Of The Woodanilling Townsite, Ben Whitfield

Resource management technical reports

A groundwater study was carried out in the townsite of Woodanilling, Western Australia. It aimed to accelerate the implementation of effective salinity management options. The study consisted of a drilling investigation, installation of a piezometer network, groundwater flow modelling and a flood risk analysis.

Field-Dependent Tilt And Birefringence Of Electroclinic Liquid Crystals: Theory And Experiment, J. V. Selinger, Peter J. Collings, R. Shashidhar

Physics & Astronomy Faculty Works

An unresolved issue in the theory of liquid crystals is the molecular basis of the electroclinic effect in the smectic-A phase. Recent x-ray scattering experiments suggest that, in a class of siloxane-containing liquid crystals, an electric field changes a state of disordered molecular tilt in random directions into a state of ordered tilt in one direction. To investigate this issue, we measure the optical tilt and birefringence of these liquid crystals as functions of field and temperature, and we develop a theory for the distribution of molecular orientations under a field. A comparison of theory and experiment confirms that these …

Space-Group Revision For 4-Formylphenylboronic Acid, Frank R. Fronczek, Nadia N. St Luce, Robert M. Strongin

Chemistry Faculty Publications and Presentations

The space group of the title compound, C₇H₇BO₃, previously reported to be P, is properly Cc. There is no disorder of the formyl group or in the H atoms of the B(OH)₂ group. Molecules lie on approximate twofold axes and are related by approximate centers, which relate all but the formyl O atom and boronic acid H atoms. The B-O distances are 1.363 (2) and 1.370 (2) Å.

Discrete Singular Convolution For The Prediction Of High Frequency Vibration Of Plates, Yibao Zhao, G. W. Wei, Y. Xiang

Research Collection Lee Kong Chian School Of Business

Theoretical analysis of high frequency vibrations is indispensable in a variety of engineering designs. Much effort has been made on this subject in the past few decades. However, there is no single technique which can be applied with confidence to various engineering structures for high frequency predictions at present. This paper introduces a novel computational approach, the discrete singular convolution (DSC) algorithm, for high frequency vibration analysis of plate structures. Square plates with six distinct boundary conditions are considered. To validate the proposed method, a completely independent approach, the Levy method, is employed to provide exact solutions for a comparison. …