Physical Sciences and Mathematics Commons^™

Dielectric Properties Of A Ferroelectric Copolymer Langmuir–Blodgett Film, Mahantappa S. Jogad, Stephen Ducharme

Stephen Ducharme Publications

We report measurements of the real (epsilon prime) and imaginary (epsilon double-prime) parts of the relative complex permittivity of a Langmuir–Blodgett film of ferroelectric copolymer of vinylidene fluoride (70%) with trifluoroethylene (30%). The measurements were made in the temperature range of 35 to 125° C, and frequency range of 19 Hz to 5 MHz. The results indicate low frequency loss due to conduction and dielectric loss peak near the ferroelectric–paraelectric phase transition.

Field Guide To The Geology Of The Harlan County Lake Area, Harlan County, Nebraska, With A History Of Events Leading To Construction Of Harlan County Dam, Robert F. Diffendal Jr., Duane R. Mohlman, R. George Corner, F. Edwin Harvey, K. J. Warren, Scott Summerside, Roger K. Pabian, Duane A. Eversoll

School of Natural Resources: Faculty Publications

The year 2002 will mark the fiftieth anniversary of completion of the Harlan County Dam and Multi-Purpose Reservoir. This seems a good time to write about the history of and reasons for building the dam, the effects of the dam and reservoir on the Republican River valley, and the geologic features seen along the shores of the lake and areas nearby. As many junior authors helped produced this educational circular, they are listed in the table of contents. All other sections were written by the senior author.

Includes July 2016 update: Addendum of photographs showing fault traces on drought-exposed lake …

Correlation Between Volcanic And Tectonic Segmentation Of Fast-Spreading Ridges: Evidence From Volcanic Structures And Lava Flow Morphology On The East Pacific Rise At 9˚-10˚N, Scott M. White, Rachel M. Haymon, D J. Fornari, Michael R. Perfit, Ken C. Macdonald

Faculty Publications

Combined analyses of volcanic features in DSL-120 sonar data and Argo I images along the ridge crest of the East Pacific Rise, 9_090–540N reveal a consistent decrease in inferred lava effusion rate toward the ends of third-order segments. The correlation of tectonic segmentation and volcanic style suggests that third-order segmentation corresponds to the volcanic segmentation of the ridge. Along-axis changes in volcanic structures (from collapse troughs to basaltic lava domes) and lava morphology (from sheet to pillow flows) coincide with the boundaries of morphologically defined third order tectonic segments of the ridge crest visible in shipboard multibeam bathymetry. Pillow lava …

Bulk And Interfacial Properties Of Quadrupolar Fluids, V.B. Warshavsky, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

We extend Teixeira and Telo da Gama’s density-functional approach [J. Phys.: Condens. Matter 3, 111 (1991)] to study the vapor–liquid phase equilibria and planar interfacial properties of quadrupolar fluids. The density profile, surface ordering, surface polarization, and surface tension of quadrupolar fluids are evaluated. Particular attention is given to the temperature and quadrupole-strength dependence. It is found that the interfacial molecular ordering can arise entirely due to the quadrupole–quadrupole interaction. It is also found that the bulk-phase properties of the quadrupolar fluids satisfy the law of correspondence states. The reduced surface potential and surface tension can be well correlated by …

Temperature Variations From Hubble Space Telescope Imagery And Spectroscopy Of Ngc 7009, R. H. Rubin, N. J. Bhatt, R. J. Dufour, B. A. Buckalew, M. J. Barlow, X.-W. Liu, P. J. Storey, B. Balick, Gary J. Ferland, J. P. Harrington, P. G. Martin

Physics and Astronomy Faculty Publications

We present new Hubble Space Telescope (HST)/WFPC2 imagery and STIS long-slit spectroscopy of the planetary nebula NGC 7009. The primary goal was to obtain high spatial resolution of the intrinsic line ratio [O III] 4364/5008 and thereby evaluate the electron temperature (T_e) and the fractional mean-square T_e variation (t_A²)across the nebula. The WFPC2 T_emap is rather uniform; almost all values are between 9000–11 000 K, with the higher T_e values closely coinciding with the inner He⁺⁺ zone. The results indicate very small values–≲0.01– for …

Karst Aquifers As Atmospheric Carbon Sinks: An Evolving Global Network Of Research Sites, Chris Groves, Joe Meiman, Joel Despain, Liu Zaihua, Daoxin Yuan

Chris Groves

Karst flow systems formed in carbonate rocks have been recognized as a sink for atmospheric carbon that originates as gaseous carbon dioxide and ends up as dissolved aqueous carbon, primarily as bicarbonate. While measurements of the magnitude of the sink associated with carbonate rock dissolution have assumed that half of the dissolved inorganic carbon leaving a given catchment comes from the mineral and half from the atmosphere, consideration of the kinetics of carbonate mineral dissolution in acid solutions suggests that the ratio is enriched in mineral-source carbon to an extent that depends on the geochemical environment of mineral/fluid contact. After …

Extraordinary Late‐Time Infrared Emission Of Type Iin Supernovae, Christopher L. Gerardy, Robert A. Fesen, Ken-Ichi Nomoto, Peter M. Garnavich

Dartmouth Scholarship

Near-infrared observations are presented for five Type IIn supernovae (SN 1995N, SN 1997ab, SN 1998S, SN 1999Z, and SN 1999el) that exhibit strong infrared excesses at late times (t > 100 days). H- and K-band emission from these objects is dominated by a continuum that rises toward longer wavelengths. The data are interpreted as thermal emission from dust, probably situated in a preexisting circumstellar nebula. The IR luminosities implied by single-temperature blackbody fits are quite large, >1041-1042 ergs s-1, and the emission evolves slowly, lasting for years after maximum light. For SN 1995N, the integrated energy release via …

Karst Aquifers As Atmospheric Carbon Sinks: An Evolving Global Network Of Research Sites, Chris Groves, Joe Meiman, Joel Despain, Liu Zaihua, Daoxin Yuan

Earth, Environmental, and Atmospheric Sciences Faculty Publications

Karst flow systems formed in carbonate rocks have been recognized as a sink for atmospheric carbon that originates as gaseous carbon dioxide and ends up as dissolved aqueous carbon, primarily as bicarbonate. While measurements of the magnitude of the sink associated with carbonate rock dissolution have assumed that half of the dissolved inorganic carbon leaving a given catchment comes from the mineral and half from the atmosphere, consideration of the kinetics of carbonate mineral dissolution in acid solutions suggests that the ratio is enriched in mineral-source carbon to an extent that depends on the geochemical environment of mineral/fluid contact. After …

Leading Neutron Production In E+ P Collisions At Hera, S. Chekanov, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Levi, A. Margotti, R. Nania, F. Palmonari, A. Pesci, G. Sartorelli, A. Zichichi, G. Aghuzumtsyan

Faculty Publications

The production of neutrons carrying at least 20% of the proton beam energy (xL > 0.2) in e+ p collisions has been studied with the ZEUS detector at HERA for a wide range of Q2, the photon virtuality, from photoproduction to deep inelastic scattering. The neutron-tagged cross section, ep → e′ Xn, is measured relative to the inclusive cross section, ep → e′ X, thereby reducing the systematic uncertainties. For xL > 0.3, the rate of neutrons in photoproduction is about half of that measured in hadroproduction, which constitutes a clear breaking of factorisation. There is about a 20% rise in the …

The Ideal Lead Time For Tornado Warnings - A Look From The Customer’S Perspective, Rick Ewald, Jared L. Guyer

United States Department of Commerce: Staff Publications

Improving the amount of advanced warning time (lead time) for tornado warnings is one of the goals spelled out in the National Weather Service (NWS) Vision 2005 Strategic Plan (1999). Since the beginning of the NWS modernization effort, tornado warning lead times have increased from four to ten minutes, with the goal of 15 mi nutes set for 2005. In concert with increasing lead times, the NWS also has goals in place for increasing the probability of detection (POD) while decreasing the false alarm rate (FAR).
Accomplishing these goals will be no easy task. Rothfusz (2000) noted that forecasters may …

Multiple Hypothesis Testing In Microarray Experiments, Sandrine Dudoit, Juliet Popper Shaffer, Jennifer C. Boldrick

U.C. Berkeley Division of Biostatistics Working Paper Series

DNA microarrays are a new and promising biotechnology which allows the monitoring of expression levels in cells for thousands of genes simultaneously. An important and common question in microarray experiments is the identification of differentially expressed genes, i.e., genes whose expression levels are associated with a response or covariate of interest. The biological question of differential expression can be restated as a problem in multiple hypothesis testing: the simultaneous test for each gene of the null hypothesis of no association between the expression levels and the responses or covariates. As a typical microarray experiment measures expression levels for thousands of …

Coverage Properties Of The Inverse Sinh Transformation And The Adjusted Wald Confidence Intervals For The Odds Ratio And The Relative Risk., Troy Allen Bowman

Electronic Theses and Dissertations

The inverse sinh transformation on the Woolf interval is used to calculate the confidence interval for the odds ratio and the relative risk in a 2 x 2 table. According to Robert Newcombe, the new interval should improve the coverage probabilities and shorten the width of the confidence interval for these ratios, but the new interval requires evaluation of coverage properties. In this thesis, we will evaluate the exact coverage properties of this modified interval in extreme cases. Also, we will compare the coverage properties of this new interval to other widely-used adjusted intervals. Through comparisons of exact coverage probabilities …

Construction Of Piecewise Linear Wavelets., Jiansheng Cao

Electronic Theses and Dissertations

It is well known that in many areas of computational mathematics, wavelet based algorithms are becoming popular for modeling and analyzing data and for providing efficient means for hierarchical data decomposition of function spaces into mutually orthogonal wavelet spaces. Wavelet construction in more than one-dimensional setting is a very challenging and important research topic. In this thesis, we first introduce the method of construction wavelets by using semi-wavelets. Second, we construct piecewise linear wavelets with smaller support over type-2 triangulations. Then, parameterized wavelets are constructed using the orthogonality conditions.

Models And Graphics In The Analysis Of Categorical Variables: The Case Of The Youth Tobacco Survey., Deborah Susan Hosler

Electronic Theses and Dissertations

Youth Tobacco Surveys have been conducted in several states in the U.S. in recent years, in order to design policies with the goal of reducing tobacco use among young people. Some primary analysis of those surveys has been done, but few analyses include modeling, and the study of independence has been addressed, mainly, in the bivariate context.

In this work contemporary methods, which are of relative recent appearance in categorical data analysis, will be examined, including logistic and log-linear modeling as well as graphical displays and correspondence analysis. These methods will be applied to data from the 2000 Tennessee Youth …

On The Construction Of Linear Prewavelets Over A Regular Triangulation., Qingbo Xue

Electronic Theses and Dissertations

In this thesis, all the possible semi-prewavelets over uniform refinements of regular triangulations have been studied. A corresponding theorem is given to ensure the linear independence of a set of different pre-wavelets obtained by summing pairs of these semi-prewavelets. This provides efficient multiresolutions of the spaces of functions over various regular triangulation domains since the bases of the orthogonal complements of the coarse spaces can be constructed very easily.

A Case Of Supercell Intensification Along A Preexisting Boundary – Clay County Nebraska Tornado Of 22 September 2001, Jared Guyer

United States Department of Commerce: Staff Publications

During the early evening hours of 22 September 2001, a supercell thunderstorm developed in south central Nebraska along an advancing cold front. The supercell initially produced an F1 tornado (Fujita 1971) in northern Clay County, Nebraska.
As the supercell propagated southeastward through Clay County, it rapidly intensified and produced a second, much stronger, tornado. The tornado produced F3 damage to three farmsteads in rural Clay County, Nebraska, along a 13 km path. The tornado was over one half km in diameter for much of its lifetime.
In accordance with research involving low-level boundaries and tornadic storms (Maddox et al. 1980; …

Development Of A Systems Engineering Model Of The Chemical Separations Process: Quarterly Progress Report 5/16/02- 8/15/02, Yitung Chen, Randy Clarksean, Darrell Pepper

Separations Campaign (TRP)

Two activities are proposed in this Phase I task: the development of systems engineering model and the refinement of the Argonne code AMUSE (Argonne Model for Universal Solvent Extraction). The detailed systems engineering model is the start of an integrated approach to the analysis of the materials separations associated with the AAA Program. A second portion of the project is to streamline and improve an integral part of the overall systems model, which is the software package AMUSE. AMUSE analyzes the UREX process and other related solvent extraction processes and defines many of the process streams that are integral to …

Design And Analysis For Melt Casting Metallic Fuel Pins Incorporating Volatile Actinides: Quarterly Progress Report 5/16/02- 8/15/02, Yitung Chen, Randy Clarksean, Darrell Pepper

Fuels Campaign (TRP)

An important aspect of the Advanced Accelerator Applications (AAA) program is the development of a casting process by which volatile actinide element (i.e., americium) can be incorporated into metallic alloy fuel pins. The traditional metal fuel casting process uses an inductively heated crucible.

This process works well for the fabrication of metal fuel pins traditionally composed of alloys of uranium and plutonium, but does not work well when highly volatile actinides are included in the melt. The problem occurs both during the extended time period required to superheat the alloy melt as well as when the chamber must be evacuated. …

Infrared Depletion Spectroscopy Of Aniline-Acetonitrile Cation And Aniline-Acetonitrile-Water Cation Clusters, H. Nagai, Naveed Piracha, T. Nakanaga

Naveed K. Piracha

The vibrational spectra of the aniline-acetonitrile^+ and the aniline-acetonitrile-water^+ cluster cations have been measured by the infrared depletion spectroscopy in the frequency region of NH and OH stretching vibrations. One absorption band was observed at 3437cm^-^1 in the infrared spectrum of the aniline-acetonitrile^+ cluster cation, and was assigned to the NH stretching vibration of free NH of aniline. As for the aniline-water-acetonitrile^+ cluster cation, three absorptions were observed at 3722, 3634 and 3247cm^-^1, which were assigned to the anti-symmetric stretching and symmetric stretching vibrations of OH of water and the stretching vibrations of NH bond interacting with water, respectively. In …

Red Rock Desert Learning Center & Wild Horse And Burro Facility: Oliver Ranch Feasibility Study, Yosemite National Institutes

Oliver Ranch Project

Yosemite National Institutes, a private, non-profit national environmental education leader, has been running successful residential science programs in national parks for 30 years in partnership with the National Park Service. The mission of YNI is to provide educational adventures in nature's classroom to inspire a personal connection to the natural world and responsible actions to sustain it. Early in 2000 in Las Vegas, a new organization, the Outside Las Vegas Foundation (OLVF), was forming. The OLVF is dedicated to preserving the federal public lands surrounding Las Vegas, enriching the experience of its visitors, enhancing the quality of life for local …

Estimation Of The Bivariate Survival Function With Generalized Bivariate Right Censored Data Structures, Sunduz Keles, Mark J. Van Der Laan, James M. Robins

U.C. Berkeley Division of Biostatistics Working Paper Series

We propose a bivariate survival function estimator for a general right censored data structure that includes a time dependent covariate process. Firstly, an initial estimator that generalizes Dabrowska's (1988) estimator is introduced. We obtain this estimator by a general methodology of constructing estimating functions in censored data models. The initial estimator is guaranteed to improve on Dabrowska's estimator and remains consistent and asymptotically linear under informative censoring schemes if the censoring mechanism is estimated consistently. We then construct an orthogonalized estimating function which results in a more robust and efficient estimator than our initial estimator. A simulation study demonstrates the …

Algebraic Methods For Computer Aided Geometric Design, Thomas W. Sederberg, Jianmin Zheng

Faculty Publications

CAGD draws from several branches of mathematics and computer science, such as approximation theory, differential geometry, and numerical analysis. This chapter reviews some of the tools of algebra and algebraic geometry that have been brought to bear on problems in CAGD.

Maximization Of The Open Circuit Voltage For Hydrogenated Amorphous Silicon N–I–P Solar Cells By Incorporation Of Protocrystalline Silicon P-Type Layers, R. J. Koval, Chi Chen, G. M. Ferreira, A. S. Ferlauto, Joshua M. Pearce, P. I. Rovira, C. R. Wronski, R. W. Collins

Joshua M. Pearce

X-Ray And Optical Variations In The Classical Be Star Γ Cassiopeia: The Discovery Of A Possible Magnetic Dynamo, Richard D. Robinson, Myron A. Smith, Gregory W. Henry

Information Systems and Engineering Management Research Publications

The classical B0.5e star γ Cassiopeia is known to be a unique X-ray source by virtue of its moderate LX (1033 ergs s-1), hard X-ray spectrum, and light curve punctuated by ubiquitous flares and slow undulations. The peculiarities of this star have led to a controversy concerning the origin of these emissions: whether they are from wind infall onto a putative degenerate companion, as in the case of normal Be/X-ray binaries, or from the Be star itself. Recently, much progress has been made to resolve this question: (1) the discovery that γ Cas is a moderately eccentric binary system (P …

Discovery Of Spectral Variability Of Markarian 421 At Tev Energies, P. T. Reynolds, Et. Al.

Physical Sciences Publications

The detection of spectral variability of the γ-ray blazar Mrk 421 at TeV energies is reported. Observations with the Whipple Observatory 10 m γ-ray telescope taken in 2000/2001 revealed exceptionally strong and long-lasting flaring activity. Flaring levels of 0.4-13 times that of the Crab Nebula flux provided sufficient statistics for a detailed study of the energy spectrum between 380 GeV and 8.2 TeV as a function of the flux level. These spectra are well described by a power law with an exponential cutoff: dN/dE ∝ E-αeimg1.gif m-2 s-1 TeV-1. There is no evidence for variation in the cutoff energy with …

Scaling, Domains, And States In The Four-Dimensional Random Field Ising Magnet, Alan Middleton

Physics - All Scholarship

The four dimensional Gaussian random field Ising magnet is investigated numerically at zero temperature, using samples up to size $64^4$, to test scaling theories and to investigate the nature of domain walls and the thermodynamic limit. As the magnetization exponent $\beta$ is more easily distinguishable from zero in four dimensions than in three dimensions, these results provide a useful test of conventional scaling theories. Results are presented for the critical behavior of the heat capacity, magnetization, and stiffness. The fractal dimensions of the domain walls at criticality are estimated. A notable difference from three dimensions is the structure of the …

(Esh) Holocene Climate Variability, Paul Andrew Mayewski, Loreen Meeker

University of Maine Office of Research Administration: Grant Reports

With the successful completion of deep drilling at Summit Greenland there is now a well-dated, high resolution, multi-parameter record of climate change (response and forcing) for the Northern Hemisphere that covers the last glacial cycle. This record reveals evidence of rapid and dramatic change in climate. Recent examination of the Holocene portion (last 11,500 years) of the Greenland record has demonstrated that, while relatively stable by comparison with glacial age climate, the Holocene does contain subdued versions of glacial age millennial scale and rapid climate change events. The Holocene is also characterized by significant annual to centennial scale variability plus …

Tilings Of Low-Genus Surfaces By Quadrilaterals, John Gregoire, Isabel Averil

Mathematical Sciences Technical Reports (MSTR)

In contribution to the classification of all tilings of low-genus surfaces, the kaleidoscopic and non-kaleidoscopic tilings by quadrilaterals are given up to genus 12. As part of their classification, the algebraic structure of the conformal tiling groups and the geometric structure of the tiles are specified. In addition, several infinite classes of tilings and tiling groups are presented.

Automated Stellar Spectral Classification And Parameterization For The Masses, Ted Von Hippel, Carlos Allende Prieto, Chris Sneden

Publications

Stellar spectroscopic classification has been successfully automated by a number of groups. Automated classification and parameterization work best when applied to a homogeneous data set, and thus these techniques primarily have been developed for and applied to large surveys. While most ongoing large spectroscopic surveys target extragalactic objects, many stellar spectra have been and will be obtained. We briefly summarize past work on automated classification and parameterization, with emphasis on the work done in our group. Accurate automated classification in the spectral type domain and parameterization in the temperature domain have been relatively easy. Automated parameterization in the metallicity domain, …

Object-Oriented Modeling And Fault Detection Of A Powder Feeder For A Laser Metal Deposition System, Robert G. Landers, Michael Gene Hilgers, Frank W. Liou, Bruce M. Mcmillin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

One of the most critical components of a laser metal deposition system is the powder feeder unit. Techniques are required to efficiently design and analyze these systems and to ensure fault tolerance during the operation. In this paper, a model of the powder feeder unit, based on object-oriented abstractions of it components, is developed. This model is modular in that specific components can be efficiently updated or replaced with components that perform a similar function. In addition, the model can be used for simulation allowing for efficient design and analysis. Assurance of the correctness of the powder feeder system is …