Physical Sciences and Mathematics Commons^™

Communications Breakdown: Revisiting The Question Of Information And Its Significance For Community Informatics Projects, William Tibben

Faculty of Informatics - Papers (Archive)

The gap between those who understand the complexities of community requirements and the information technologists who can build the technologies represents a central focus of concern with Community Informatics (CI) research. This paper explores how different assumptions about the utility of information leads to poor communication between researchers and practitioners. Braman’s four-part hierarchy is a useful vehicle to investigate this as she seeks to include a range of actors such as policy makers, technologists and community members. A number of case study examples are explored to illustrate the value of Braman’s work for CI.

Stress Evolution In Nanocrystalline Diamond Films Produced By Chemical Vapor Deposition, Hao Li, Brian W. Sheldon, Abhishek Kothari, Zhigang Ban, Barbara L. Walden

Faculty Scholarship

Nanocrystalline diamond films were grown on silicon substrates by microwave plasma enhanced chemical vapor deposition with 1% methane, 2%–10% hydrogen, and argon. High resolution transmission electron microscope images and selected area electron diffraction patterns confirm that the films consist of 10–20 nm sized diamond grains. The residual and intrinsic stresses were investigated using wafer curvature. Intrinsic stresses were always tensile, with higher H₂ concentrations generally leading to higher stresses. Annealing the films in a hydrogen plasma significantly increased these stresses. These hydrogen induced changes also appear to alter stress levels and stress gradients during the growth process itself. Raman …

Validity, Identification, And Distribution Of The Roundscale Spearfish, Tetrapturus Georgii (Teleostei: Istiophoridae): Morphological And Molecular Evidence, Mahmood S. Shivji, Jennifer E. Magnussen, Lawrence R. Beerkircher, George Hinteregger, Dennis W. Lee, Joseph E. Serafy, Eric D. Prince

Marine & Environmental Sciences Faculty Articles

The roundscale spearfish, Tetrapturus georgii Lowe, 1840, is known only from four specimens from the Mediterranean and eastern North Atlantic. Additional specimens have not been identified since 1961, making the validity and distribution of this species unclear. Analysis of 16 billfish specimens from the western North Atlantic on the basis of scale morphology, anus position, and mitochondrial DNA confirms the validity of this species and extends its distribution. Mid-lateral scales are soft, notably rounded anteriorly, and bear 2–3 points distinct from those of the sympatric longbill spearfish (Tetrapturus pfluegeri Robins and de Sylva, 1963) and white marlin (Tetrapturus …

Stratospheric Variability And Trends In Models Used For The Ipcc Ar4, P. M. De F. Forster, Eugene Cordero

Eugene C. Cordero

Atmosphere and ocean general circulation model (AOGCM) experiments for the Intergovernmental Panel on Climate Change Fourth Assessment Report (AR4) are analyzed to better understand model variability and assess the importance of various forcing mechanisms on stratospheric trends during the 20th century. While models represent the climatology of the stratosphere reasonably well in comparison with NCEP reanalysis, there are biases and large variability among models. In general, AOGCMs are cooler than NCEP throughout the stratosphere, with the largest differences in the tropics. Around half the AOGCMs have a top level beneath ~2 hPa and show a significant cold bias in their …

Assessment Of Temperature, Trace Species, And Ozone In Chemistry-Climate Model Simulations Of The Recent Past, V. Eyring, N. Butchart, D. W. Waugh, H. Akiyoshi, J. Austin, S. Bekki, G. E. Bodeker, B. A. Boville, C. Brühl, M. P. Chipperfield, E. Cordero, M. Dameris, M. Deushi, V. E. Fioletov, S. M. Frith, R. R. Garcia, A. Gettelman, M. A. Giorgetta, V. Grewe, L. Jourdain, D. E. Kinnison, E. Mancini, E. Manzini, M. Marchand, D. R. Marsh, T. Nagashima, P. A. Newman, J. E. Nielsen, S. Pawson, G. Pitari, D. A. Plummer, E. Rozanov, M. Schraner, T. G. Shepherd, K. Shibata, R. S. Stolarski, H. Struthers, W. Tian, M. Yoshiki

Eugene C. Cordero

[1] Simulations of the stratosphere from thirteen coupled chemistry-climate models (CCMs) are evaluated to provide guidance for the interpretation of ozone predictions made by the same CCMs. The focus of the evaluation is on how well the fields and processes that are important for determining the ozone distribution are represented in the simulations of the recent past. The core period of the evaluation is from 1980 to 1999 but long-term trends are compared for an extended period (1960–2004). Comparisons of polar high-latitude temperatures show that most CCMs have only small biases in the Northern Hemisphere in winter and spring, but …

Abstract Semilinear Itó-Volterra Integro-Differential Stochastic Evolution Equations, David N. Keck, Mark A. Mckibben

Mathematics Faculty Publications

We consider a class of abstract semilinear stochastic Volterra integrodifferential equations in a real separable Hilbert space. The global existence and uniqueness of a mild solution, as well as a perturbation result, are established under the so-called Caratheodory growth conditions on the nonlinearities. An approximation result is then established, followed by an analogous result concerning a so-called McKean-Vlasov integrodi fferential equation, and then a brief commentary on the extension of the main results to the time-dependent case. The paper ends with a discussion of some concrete examples to illustrate the abstract theory.

Status Of The Common Snook (Centropomus Undecimalis) In Texas, Kevin L. Pope, David R. Blankinship, Mark Fisher, Reynaldo Patiño

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Catch data are summarized for common snook (Centropomus undecimalis) from 1975 through 2004 from the lower Laguna Madre, the only area along the Texas coast where common snook are routinely captured. Catch rates of common snook were low < 1 common snook per gill net set) and varied among years, as did size structure. Based on the catch rate and size structure data, the adult common snook population is characterized by low abundance and erratic recruitment (i.e., missing or extremely weak year-classes are common). Additional comments on the status of common snook in Texas are provided.

Comments On “On The Distribution Of The Product Of Independent Rayleigh Random Variables”, Saralees Nadarajah, Samuel Kotz

Department of Statistics: Faculty Publications

It is pointed out that the result in Salo et al. “The Distribution of the Product of Independent Rayleigh Random Variables” IEEE Trans. Antennas Propag., vol. 54, pp. 639–643, Feb. 2006, is a particular case of a much more general result known since the 1970s. A general technique (known as the H function technique) is described that can be used derive a wide range of results similar to Salo et al.

Comments On “On The Distribution Of The Product Of Independent Rayleigh Random Variables”, Saralees Nadarajah, Samuel Kotz

Department of Statistics: Faculty Publications

It is pointed out that the result in Salo et al. “The Distribution of the Product of Independent Rayleigh Random Variables” IEEE Trans. Antennas Propag., vol. 54, pp. 639–643, Feb. 2006, is a particular case of a much more general result known since the 1970s. A general technique (known as the function technique) is described that can be used derive a wide range of results similar to Salo et al.

A Preliminary Study Of Sulfide Mineral Formation In Methane-Rich, Marine Sediments Associated With Anaerobic Methane Oxidation, Cascadia Continental Margin, Offshore Oregon, David Deigert, Walter S. Borowski

EKU Faculty and Staff Scholarship

Within gas hydrate settings, sulfide mineralization in marine sediments is likely controlled by two microbially-mediated, sulfate-depleting processes: anaerobic methane oxidation (AMO) and sulfate reduction. If large amounts of methane are delivered to the sulfate-methane interface (SMI), predominantly by diffusion, larger amounts of solid sulfide sulfur should occur there as dissolved sulfide combines with iron, forming an authigenic precipitate. We measure the amount of diagenetic sulfide sulfur at three locations in the Hydrate Ridge vicinity by extracting the bulk sedimentary sulfide-phase minerals (S^o, FeS, and FeS₂) through chromium reduction, precipitating sulfide sulfur as silver sulfide, and gravimetrically …

Refuge Update – November/December 2006, Volume 3, Number 6

RefugeUpdate (USFWS-NWRS)

Table of Contents:

Least Bell’s Vireos Are Back, page 3 San Joaquin River National Wildlife Refuge hosted totally unexpected residents last year.

Managing Ocean Wildlife, page 5 A new agreement should help in managing marine resources.

Focus on . . . Endangered Species, pages 10-21 Whether it’s the fastest land mammal or the tiniest mussel, refuges work on behalf of endangered species.

Peeping at Peeps, page 24 Shorebirds can be tough to identify. Classroom and fields trips helped.

A Simplified Model For Growth Factor Induced Healing Of Wounds, F. J. Vermolen, E. Van Baaren, J. A. Adam

Mathematics & Statistics Faculty Publications

A mathematical model is developed for the rate of healing of a circular or elliptic wound. In this paper the regeneration, decay and transport of a generic 'growth factor', which induces the healing of the wound, is taken into account. Further, an equation of motion is derived for radial healing of a circular wound. The expressions for the equation of motion and the distribution of the growth factor are related in such a way that no healing occurs if the growth factor concentration at the wound edge is below a threshold value. In this paper we investigate the influence of …

Quantum Dot Potentials: Symanzik Scaling, Resurgent Expansions, And Quantum Dynamics, Andrey S. Surzhykov, Michael Lubasch, Jean Zinn-Justin, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

This article is concerned with a special class of the "double-well- like" potentials that occur naturally in the analysis of finite quantum systems. Special attention is paid, in particular, to the so-called Fokker-Planck potential, which has a particular property: the perturbation series for the ground-state energy vanishes to all orders in the coupling parameter, but the actual ground-state energy is positive and dominated by instanton configurations of the form exp (-a g), where a is the instanton action. The instanton effects are most naturally taken into account within the modified Bohr-Sommerfeld quantization conditions whose expansion leads to the generalized perturbative …

Analysis Of Two-Dimensional Photoelectron Momentum Spectra And The Effect Of The Long-Range Coulomb Potential In Single Ionization Of Atoms By Intense Lasers, Zhangjin Chen, Toru Morishita, Anh-Thu Le, M. Wickenhauser, X. M. Tong, C. D. Lin

Physics Faculty Research & Creative Works

Two-dimensional (2D) electron momentum distributions and energy spectra for multiphoton ionization of atoms by intense laser pulses, calculated by solving the time-dependent Schrödinger equation (TDSE) for different wavelengths and intensities, are compared to those predicted by the strong-field approximation (SFA). It is shown that the momentum spectra at low energies between the TDSE and SFA are quite different and the differences arise largely from the absence of a long-range Coulomb interaction in the SFA. We further found that the low-energy 2D momentum spectra from the TDSE exhibit ubiquitous fanlike features where the number of stripes is due to a single …

Pend Oreille River, Box Canyon Model: Model Development And Calibration, Robert Leslie Annear, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The purpose of this study was to improve the existing Version 3.0 application of CE-QUAL-W2 of the Pend Oreille River between Box Canyon Dam and Albeni Falls Dam by performing the tasks outlined above. In addition, the use of field data from 2004 as an additional calibration year would improve the confidence in the model’s predictive ability for temperature. The model simulations were run from January 1st to December 31st in each of the 3 years of model simulation: 1997, 1998 and 2004.

The model chosen for development is CE-QUAL-W2 Version 3.5 (Cole and Wells, 2006). This is a twodimensional …

Emergence Of The Fuzzy Horizon Through Gravitational Collapse, Anand Murugan '07, Vatche Sahakian

All HMC Faculty Publications and Research

For a large enough Schwarzschild black hole, the horizon is a region of space where gravitational forces are weak; yet it is also a region leading to numerous puzzles connected to stringy physics. In this work, we analyze the process of gravitational collapse and black hole formation in the context of light-cone M-theory. We find that, as a shell of matter contracts and is about to reveal a black hole horizon, it undergoes a thermodynamic phase transition. This involves the binding of D0 branes into D2’s, and the new phase leads to large membranes of the size of the horizon. …

Fluorescence Polarization Of Helium Negative-Ion Resonances Excited By Polarized Electron Impact, J. W. Maseberg, Timothy J. Gay

Timothy J. Gay Publications

We have investigated helium (1s3d) ³D → (1s2p) ³P (588 nm) fluorescence produced by electron impact excitation in the vicinity of the (2s²2p) ²P and (2s2p²) ²D negative-ion resonances at 57.2 and 58.3 eV, respectively. In contrast to previous work, we use spin-polarized incident electrons and report the relative Stokes parameters P₁, P₂, and P₃ in the 55–60 eV region. Our failure to see discernable resonance effects in P₂ indicates that even though the lifetime of these resonances is significant (~10 fs), magnetic forces acting on …

Production Of Excited Atomic Hydrogen And Deuterium From H2 And D2 Photodissociation, J. D. Bozek, J. E. Furst, Timothy J. Gay, H. Gould, A. L. D. Kilcoyne, J. R. Machacek, F. Martin, K. W. Mclaughlin, J. L. Sanz-Vicario

Timothy J. Gay Publications

We have measured the production of both Lyα and Hα fluorescence from atomic H and D for the photodissociation of H₂ and D₂ by linearly polarized photons with energies between 24 and 60 eV. In this energy range, excited photofragments result primarily from the production of doubly excited molecular species which promptly autoionize or dissociate into two neutrals. Our data are compared with ab initio calculations of the dissociation process, in which both doubly excited state production and prompt ionization (non resonant) channels are considered. Agreement between our experimental data and that of earlier work, and with our …

Nickel(Ii) And Cobalt(Ii) Nitrate And Chloride Networks With 2-Aminopyrimidine, Robert D. Pike, Mi Jung Lim, Ellen A. L. Wilcox, Tristan A. Tronic

Arts & Sciences Articles

The coordination chemistry of 2-aminopyrimidine (PymNH2) with nickel(II) and cobalt(II) nitrate and chloride is reported, including seven new X-ray crystal structures. Two [Ni(NO3)2(PymNH2)2(OH2)] isomers were found (A: C2/c, a=13.3006(5), b=7.9727(3), c=28.5453(11), β=101.758(2), V=2963.48(19), Z=8 and B·1/2 acetone: P21/c, a=7.66060(10), b=10.6792(2), c=20.6790(3), β=100.2970(10), 1664.48(5), Z=4). In both cases one nitrate is monodentate and the other is chelating and the PymNH2 ligands coordinate through ring nitrogen atoms. Hydrogen bonding results in double sheet structure for isomer A, and a three dimensional channeled network for isomer B. [Co(NO3)2(PymNH2)2(OH2)] ( …

On T-Pure And Almost Pure Exact Sequences Of Lca Groups, Peter Loth

Mathematics Faculty Publications

A proper short exact sequence in the category of locally compact abelian groups is said to be t-pure if φ(A) is a topologically pure subgroup of B, that is, if for all positive integers n. We establish conditions under which t-pure exact sequences split and determine those locally compact abelian groups K ⊕ D (where K is compactly generated and D is discrete) which are t-pure injective or t-pure projective. Calling the extension (*) almost pure if for all positive integers n, we obtain a complete description of the almost pure injectives and almost pure projectives in the category of …

On The Cohomology Of Spatial Polygons In Euclidean Spaces, Vehbi Emrah Paksoy

Mathematics Faculty Articles

Space of spatial polygons in Euclidean spaces has been studied extensively in [3, 1, 2]. There is a beautiful description of cohomology in [1]. In this paper we introduce another, easy to compute method to obtain the cohomology without using toric variety arguments. We also give a criterion for a polygon space to be Fano, thus, having ample anticanonical class.

Maximal Clifford Semigroups Of Matrices, Edmond W. H. Lee

Mathematics Faculty Articles

All maximal Clifford semigroups of matrices are identified up to isomorphism. If the ground field of the matrices is finite, then there exists a unique Clifford semigroup of maximum order.

Submicrosecond Dynamics Of Water Explosive Boiling And Lift-Off From Laser-Heated Silicon Surfaces, S. I. Kudryashov, S. D. Allen

Mechanical Engineering - Daytona Beach

Explosive boiling and lift-off of a thin layer of micron-sized transparent water droplets from an absorbing Si substrate heated by a nanosecond KrF laser were studied using a contact photoacoustic technique. The compressive photoacoustic response increases steeply to an asymptotic value on the order of the water critical pressure starting at a threshold laser fluence of 0.20 J cm2, where lift-off of the water layer also occurs. Above this threshold, several reproducible discrete multimegahertz components are revealed in Fourier spectra of the acoustic transients, corresponding to nanosecond oscillations of steam bubbles inside the water droplets on the microsecond time scale …

Summing Cubes By Counting Rectangles, Arthur T. Benjamin, Jennifer J. Quinn, Calyssa Wurtz

All HMC Faculty Publications and Research

No abstract provided in this article.

Self-Avoiding Walks And Fibonacci Numbers, Arthur T. Benjamin

All HMC Faculty Publications and Research

By combinatorial arguments, we prove that the number of self-avoiding walks on the strip {0, 1} × Z is 8F_n − 4 when n is odd and is 8F_n − n when n is even. Also, when backwards moves are prohibited, we derive simple expressions for the number of length n self-avoiding walks on {0, 1} × Z, Z × Z, the triangular lattice, and the cubic lattice.

How Effective Is Security Screening Of Airline Passengers?, Susan E. Martonosi, Arnold Barnett

All HMC Faculty Publications and Research

With a simple mathematical model, we explored the antiterrorist effectiveness of airport passenger prescreening systems. Supporters of these systems often emphasize the need to identify the most suspicious passengers, but they ignore the point that such identification does little good unless dangerous items can actually be detected. Critics often focus on terrorists' ability to probe the system and thereby thwart it, but ignore the possibility that the very act of probing can deter attempts at sabotage that would have succeeded. Using the model to make some preliminary assessments about security policy, we find that an improved baseline level of screening …

Central Dysregulation Of The Hypothalamic-Pituitary-Adrenal Axis In Neuron-Specific Proopiomelanocortin-Deficient Mice, James L. Smart, Virgine Tolle, Veronica Otero-Corchon, Malcolm J. Low

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.

Dynamic Modeling And Statistical Analysis Of Event Times, Edsel A. Pena

Faculty Publications

This review article provides an overview of recent work in the modeling and analysis of recurrent events arising in engineering, reliability, public health, biomedicine and other areas. Recurrent event modeling possesses unique facets making it different and more difficult to handle than single event settings. For instance, the impact of an increasing number of event occurrences needs to be taken into account, the effects of covariates should be considered, potential association among the interevent times within a unit cannot be ignored, and the effects of performed interventions after each event occurrence need to be factored in. A recent general class …

Gray Wolf Biology Questions And Answers

Rocky Mountain Wolf Recovery: Annual Reports

1) Why was the gray wolf listed as endangered?
2) What types of habitat do wolves use?
3) Do wolves need wilderness areas to survive? Can they survive near urban areas?
4) How far do wolves travel?
5) What do wolves eat?
6) If wolf numbers get too high will deer and elk be eliminated?
7) How do wolves in an area affect deer hunting?
8) Do wolves really take the old, young, sick, starving, or injured animals?
9) Do wolves kill more than they can eat?
10) Does the presence of wolves affect the numbers of animals other than …

Wmi Outdoor News Bulletin * November 2006, Volume 60, No. 10

Wildlife Management Institute Outdoor News Bulletin

Contents:

• North American Bird Species Shown to be Susceptible to Avian Influenza

• Longleaf pine restoration gets huge boost from Conservation Reserve Program

• Controversy still stalking elk feedgrounds in Wyoming

• Predator/prey workshop to be held at North American Conference

• New book gets rave notice

• With dove vote, Michiganders shoot science-based wildlife management in the foot

• Geothermal energy issue still boiling at the Valles Caldera National Preserve

• 72nd North American Wildlife and Natural Resources Conference registration

• Northeast states get positively proactive on State Wildlife Actions Plans

• Nominations sought for 2007 northern bobwhite …