Digital Commons Network^™

Book Review: Stargazer: The Life And Times Of The Telescope, T. D. Oswalt

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This document is Dr. Oswalt’s review of Stargazer : the Life and Times of the Telescope by Fred Watson. Da Capo, 2004 342p, 0306814323 $24.95

Resource-Based View Of Knowledge Management For Competitive Advantage, Leila A. Halawi, Jay E. Aronson, Richard V. Mccarthy

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We are not only in a new millennium, but also in a new era: the knowledge era. Sustainable competitive advantage is dependent on building and exploiting core competencies. The resource-based view (RBV) of the firm defines a strategic asset as one that is rare, valuable, imperfectly imitiable and non-substitutable. Knowledge is seen as a strategic asset with the potential to be a source of competitive advantage for an organization. In this paper, we provide a model that examines how and why knowledge management (KM) can be sued to create competitive advantage from the RBV of the firm.

Faint Blue Objects In The Hubble Deep Field–South Revealed: White Dwarfs, Subdwarfs, And Quasars, Mukremin Kilic, Ted Von Hippel, Et Al.

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We explore the nature of the faint blue objects in the Hubble Deep Field–South. We have derived proper motions for the point sources in the Hubble Deep Field–South using a 3 yr baseline. Combining our proper-motion measurements with spectral energy distribution fitting enabled us to identify four quasars and 42 stars, including three white dwarf candidates. Two of these white dwarf candidates, HDF-S 1444 and 895, are found to display significant proper motion, 21:1±7:9 and 34:9 ± 8:0 mas yr ^-1, and are consistent with being thick-disk or halo white dwarfs located at ̴2 kpc. The other faint …

Water And Wastewater Systems In New Mexico: A Statutory Review And Comparison, Utton Transboundary Resources Center, Office Of The State Engineer, Institute Of Public Law (Ipl) Unmsol

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No abstract provided.

Book Review: The Scientific Legacy Of Fred Hoyle, T. D. Oswalt

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This document is Dr. Oswalt’s review of The Scientific Legacy of Fred Hoyle ed. by Douglas Gough Cambridge, 2004 249p, 0521824486 $75.00.

Coordinated Cluster/Double Star Observations Of Dayside Reconnection Signatures, M. W. Dunlop, M. G. G. T. Taylor, J. A. Davies, C. J. Owen, F. Pitout, A. N. Fazakerley, K. Nykyri, Et Al.

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The recent launch of the equatorial spacecraft of the Double Star mission, TC-1, has provided an unprecedented opportunity to monitor the southern hemisphere dayside magnetopause boundary layer in conjunction with northern hemisphere observations by the quartet of Cluster spacecraft. We present first results of one such situation where, on 6 April 2004, both Cluster and the Double Star TC-1 spacecraft were on outbound transits through the dawnside magnetosphere. The observations are consistent with ongoing reconnection on the dayside magnetopause, resulting in a series of flux transfer events (FTEs) seen both at Cluster and TC-1, which appear to lie north and …

Acoustic Waves Generated By Gusty Flow Over Hilly Terrain, R. L. Walterscheid, Michael P. Hickey Ph.D.

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We examine the generation of acoustic waves by gusty flow over hilly terrain. We use simple theoretical models of the interaction between terrain and eddies and a linear model of acoustic-gravity wave propagation. The calculations presented here suggest that over a dense array of geographically extensive sources orographically generated vertically propagating acoustic waves can be a significant cause of thermospheric heating. This heating may account in good part for the thermospheric hot spot near the Andes reported by Meriwether et al. (1996, 1997).

Excess Infrared Radiation From The Massive Daz White Dwarf Gd 362: A Debris Disk?, Mukremin Kilic, Ted Von Hippel, Et Al.

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We report the discovery of excess K-band radiation from the massive DAZ white dwarf star GD 362. Combining infrared photometric and spectroscopic observations, we show that the excess radiation cannot be explained by a stellar or substellar companion, and is likely to be caused by a debris disk. This would be only the second such system known, discovered 18 years after G29-38, the only single white dwarf currently known to be orbited by circumstellar dust. Both of these systems favor a model with accretion from a surrounding debris disk to explain the metal abundances observed in DAZ white dwarfs. …

Deep Photometry Of The Globular Cluster M5: Distance Estimates From White Dwarf And Main-Sequence Stars, Andrew C. Layden, Ted Von Hippel, Et Al.

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We present deep VI photometry of stars in the globular cluster M5 (NGC 5904) based on images taken with the Hubble Space Telescope. The resulting color-magnitude diagram reaches below V ≈27 mag, revealing the upper 2–3 mag of the white dwarf cooling sequence and main-sequence stars 8 mag and more below the turnoff. We fit the main sequence to subdwarfs of known parallax to obtain a true distance modulus of (m ̶ M )₀ = 14:45 ± 0:11 mag. A second distance estimate based on fitting the cluster white dwarf sequence to field white dwarfs with known parallax …

Integration Of The Shel Model With The Flight Operational Quality Assurance (Foqa) Program, James T. Schultz, Scott Forn, Marian C. Schultz

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The SHEL Model has been used to explore relationships between liveware, environmental, hardware and software factors. This study attempts to integrate Flight Operational Quality Assurance (FOQA) program data with the SHEL model. Aircraft record data that can be used to monitor the human interface within the entire system, plus identify faults and potential failures within the system before a major accident or incident occurs. These data have existed for over four decades, and FOQA offers a way to both analyze and act upon them. The relationships between the SHEL model and FOQA data can help to ensure our nation's skies …

Galactic Open Clusters, Ted Von Hippel

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The study of open clusters has a classic feel to it since the subject predates anyone alive today. Despite the age of this topic, I show via an ADS search that its relevance and importance in astronomy has grown faster in the last few decades than astronomy in general. This is surely due to both technical reasons and the interconnection of the field of stellar evolution to many branches of astronomy. In this review, I outline what we know today about open clusters and what they have taught us about a range of topics from stellar evolution to Galactic structure …

Book Review: Observing Variable Stars, Novae, And Supernovae, T. D. Oswalt

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This document is Dr. Oswalt’s review of Observing Variable Stars, Novae, and Supernovae by Gerald North with Nick James Cambridge, 2004 230p, 0521820472 $45.00.

Chemical Composition In The Globular Cluster M71 From Keck Hires Spectra Of Turnoff Stars, Ann Merchant Boesgaard, Jeremy R. King, Ann Marie Cody, Alex Stephens, Constantine P. Deliyannis

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We have made observations with the Keck I telescope and HIRES at a resolution of ∼45,000 of five nearly identical stars at the turn-off of the metal-rich globular cluster M 71. Our mean Fe abundance, [Fe/H]=-0.80 +-0.02, is in excellent agreement with previous cluster determinations from both giants and near-turnoff stars. There is no clear evidence for any star-to-star abundance differences or correlations in our sample. Abundance ratios of the Fe-peak elements (Cr, Ni) are similar to Fe. The turn-off stars in M71 have remarkably consistent enhancements of 0.2 - 0.3 dex in [Si/Fe], [Ca/Fe] and [Ti/Fe] -- like the …

Beryllium Enhancement As Evidence For Accretion In A Lithium-Rich F Dwarf, Johanna F. Ashwell, R D. Jeffries, Barry Smalley, C P. Deliyannis, Aaron Steinhauer, Jeremy R. King

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The early F dwarf star ``J37'' in the open cluster NGC6633 shows an unusual pattern of photospheric abundances, including an order of magnitude enhancement of lithium and iron-peak elements, but an under-abundance of carbon. As a consequence of its thin convection zone these anomalies have been attributed to either radiative diffusion or the accretion of hydrogen-depleted material. By comparing high resolution VLT/UVES spectra of J37 (and other F stars in NGC 6633) with syntheses of the Be ii doublet region at 3131 Ang, we establish that J37 also has a Be abundance (A(Be)=3.0+/-0.5) that is at least ten times the …

Co Line Emission And Absorption From The Hl Tauri Disk-Where Is All The Dust?, Sean D. Brittain, Terrence W. Rettig, Theodore Simon, Craig Kulesa

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We present high-resolution infrared spectra of HL Tau, a heavily embedded young star. The spectra exhibit broad emission lines of 12CO gas-phase molecules, as well as narrow absorption lines of 12CO, 13CO, and C18O. The broad emission lines of vibrationally excited 12CO are dominated by the hot (T ~ 1500 K) inner disk. The narrow absorption lines of CO are found to originate from the circumstellar gas at a temperature of ~100 K. The 12CO column density for this cooler material [(7.5 ± 0.2) × 1018 cm-2] indicates a large column of absorbing gas along the line of sight. In …

Where Are The Magnetic White Dwarfs With Detached, Nondegenerate Companions?, James W. Liebert, Dayal T. Wickramsinghe, Gary D. Schmidt, Nicole M. Silvestri, T. D. Oswalt, Et Al.

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The Sloan Digital Sky Survey has already more than doubled the sample of white dwarfs with spectral classifications, the subset with detached M dwarf companions, and the subset of magnetic white dwarfs. In the course of assessing these new discoveries, we have noticed a curious, unexpected property of the total lists of magnetic white dwarfs and of white dwarf plus main-sequence binaries: there appears to be virtually zero overlap between the two samples! No confirmed magnetic white dwarf has yet been found in such a pairing with a main-sequence star. The same statement can be made for the samples of …

Antiphase Oh And Oi Airglow Emissions Induced By A Short-Period Ducted Gravity Wave, Jonathan B. Snively, Victor P. Pasko

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"Numerical simulation of a ducted gravity wave event suggests that OH (8,3) and O(1S) 557.7 nm airglow emissions layers may exhibit opposite-phase intensities when perturbed by a short-period wave undergoing vertical reflection. This effect arises due to the time and temperature dependance of the OH excitation reaction, coupled with the linear polarization properties of vertically-standing waves."

Uaa Student Showcase Journal: Recognizing Excellence (2005), N/A N/A

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No abstract provided.

Physical Processes In Acoustic Wave Heating Of The Thermosphere, G. Schubert, Michael P. Hickey Ph.D., R. L. Walterscheid

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Upward propagating acoustic waves heat the atmosphere at essentially all heights due to effects of viscous dissipation, sensible heat flux divergence, and Eulerian drift work. Acoustic wave-induced pressure gradient work provides a cooling effect at all heights, but this is overwhelmed by the heating processes. Eulerian drift work and wave-induced pressure gradient work dominate the energy balance, but they nearly cancel at most altitudes, leaving their difference, together with viscous dissipation and sensible heat flux divergence to heat the atmosphere. Acoustic waves are very different from gravity waves which cool the upper atmosphere through the effect of sensible heat flux …

Grb 040403: A Faint X-Ray Rich Gamma-Ray Burst Discovered By Integral, S. Mereghetti, D. Götz, M. I. Andersen, A. Castro-Tirado, F. Frontera, F Frontera, J Gorosabel, Dieter H. Hartmann, J Hjorth, R Hudec, G Pizzichini, N Produit, A Tarana, M Topinka, P Ubertini, A Deugarte

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GRB 040403 is one of the faintest gamma-ray bursts for which a rapid and accurate localization has been obtained. Here we report on the gamma-ray properties of this burst, based on observations with the IBIS instrument aboard INTEGRAL, and the results of searches for its optical afterglow. The steep spectrum (power law photon index =1.9 in the 20–200 keV range) implies that GRB 040403 is most likely an X-ray rich burst. Our optical limit of R >24.2 at 16.5 h after the burst, indicates a rather faint afterglow, similar to those seen in other relatively soft and faint bursts.

The Influence Of Visibility, Cloud Ceiling, Financial Incentive, And Personality Factors On General Aviation Pilots' Willingness To Take Off Into Marginal Weather, Part I: The Data And Preliminary Conclusions, William Knecht, Howard Harris, Scott Shappell

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Adverse weather is the leading cause of fatalities in general aviation (GA). In this research, influences of ground visibility, cloud ceiling height, financial incentive, and personality were tested on 60 GA pilots' willingness to take off into simulated adverse weather. Results suggested that pilots do not see "weather" as a monolithic cognitive construct but, rather, as an interaction between its separate factors. This is supported by the finding that the multiplicative statistical effect of visibility and ceiling could better predict takeoff than could the linear effect of either variable considered separately. Also found was a statistical trend toward financial incentive …

From Young And Hot To Old And Cold: Comparing White Dwarf Cooling Theory To Main-Sequence Stellar Evolution In Open Clusters, Ted Von Hippel

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I explore the current ability of both white dwarf cooling theory and main-sequence stellar evolution theory to accurately determine stellar population ages by comparing ages derived using both techniques for open clusters ranging from 0.1 to 4 Gyr. I find good agreement between white dwarf and main-sequence evolutionary ages over the entire age range currently available for study. I also find that directly comparing main-sequence turnoff ages to white dwarf ages is only weakly sensitive to realistic levels of errors in cluster distance, metallicity, and reddening. Additional detailed comparisons between white dwarf and main-sequence ages have tremendous potential to refine …

Integral/Spi Limits On Electron-Positron Annihilation Radiation From The Galactic Plane, B. J. Teegarden, K. Watanabe, P. Jean, J. Knödlseder, V. Lonjou, J. P. Roques, G. K. Skinner, P. Von Ballmoos, G. Weidenspointer, A Bazzano, Y M. Butt, A Decourchelle, A C. Fabian, A Goldwurm, M Gudel, D C. Hannikainen, Dieter H. Hartmann

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The center of our Galaxy is a known strong source of electron-positron 511 keV annihilation radiation. Thus far, however, there have been no reliable detection of annihilation radiation outside of the central radian of our Galaxy. One of the primary objectives of the INTEGRAL (International Gamma-Ray Astrophysics Laboratory mission, resolution, coded-apeture gamma-ray telescope with an unprecedented combination of sensitivity, angular resolution, and energy resolution. We resport results from the first 10 months of observation. During this period a significant fraction of the observing time was spent in or near the Galactic plan. No positive annihilation flux was detected outside of …

Numerical Simulation Of Live Chaparral Fire Behavior Using Firetec, Lulu Sun, Xiangyang Zhou, Shankar Mahalingam, Jesse Canfield, Rodman Linn

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Fire spread through chaparral fuels is a significant feature of wildland fire in southern California. In order to study the detailed physical processes involved during fire spread, FIRETEC, a coupled atmosphere/wildfire behavior model was refined to examine chaparral fire behavior. FIRETEC combines a sophisticated fine-scale model to simulate a three- dimensional wildfire, moving over a terrain-following finite volume grid, with the motions of the local atmosphere. It accounts for the microscopic details of a fire with macroscopic resolution by dividing quantities into mean and fluctuating parts and the resulting transport equations are solved by using a finite difference method. In …

Book Review: The New Amateur Astronomer, T. D. Oswalt

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This document is Dr. Oswalt’s review of The New Amateur Astronomer by Martin Mobberley. Springer, 2004 229p, 1852336633 $34.95

The Chromospheric Activity And Ages Of M Dwarf Stars In Wide Binary Systems, Nicole M. Silvesteri, T. D. Oswalt, Suzanne L. Hawley

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We investigate the relationship between age and chromospheric activity for 139 M dwarf stars in wide binary systems with white dwarf companions. The age of each system is determined from the cooling age of its white dwarf component. The current limit for activity-age relations found for M dwarfs in open clusters is 4 Gyr. Our unique approach to finding ages for M stars allows for the exploration of this relationship at ages older than 4 Gyr. The general trend of stars remaining active for a longer time at later spectral type is confirmed. However, our larger sample and greater age …

The Dyad Theory Of Classical And Quantum Physics, Preston Jones

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The 4-space equations of hydrodynamics, electrodynamics, and quantum mechanics are developed using the dyad calculus. Gravity is found to couple hydrodynamics, electrodynamics, and quantum mechanics through the 4- space metric and differential operator. Expanding the 4-space equations of electrodynamics a time varying metric is shown to dissipate electromagnetic energy.

Robust Control Techniques For State Tracking In The Presence Of Variable Time Delays, Jarrett Goodell, Marc Compere, Miguel Simon, Wilford Smith, Ronnie Wright, Mark Brudnak

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In this paper, a distributed driver-in-the-Ioop and hardware-in-the-Ioop simulator is described with a driver on a motion simulator at the U.S. Army TARDEC Ground Vehicle Simulation Laboratory (GVSL). Realistic power system response is achieved by linking the driver in the GVSL with a full-sized hybrid electric power system located 2,450 miles away at the TARDEC Power and Energy Systems Integration Laboratory (P&E SIL), which is developed and maintained by Science Applications International Corporation (SAIC). The goal is to close the loop between the GVSL and P&E SIL over the Internet to provide a realistic driving experience in addition to realistic …

A Full-Wave Investigation Of The Use Of A ‘‘Cancellation Factor’’ In Gravity Wave–Oh Airglow Interaction Studies, Michael P. Hickey Ph.D., Yonghui Yu

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Atmospheric gravity waves (GWs) perturb minor species involved in the chemical reactions of airglow emissions in the upper mesosphere and lower thermosphere. In order to determine gravity wave fluxes and the forcing effects of gravity waves on the mean state (which are proportional to the square of the wave amplitude), it is essential that the amplitude of airglow brightness fluctuation be related to the amplitude of major gas density fluctuation in a deterministic way. This has been achieved through detailed modeling combining gravity wave dynamics described using a full-wave model with the chemistry relevant to the airglow emission of interest. …

Maine Horseshoe Crab (Limulus Polyphemus) Spawning Surveys, 2004, Susanne Schaller, Peter Thayer, Sherry Hanson, Shari Latulippe, Elizabeth Solet

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The Maine Horseshoe Crab Surveys were begun in 2001 to establish quantitative baseline data and determine whether horseshoe crab (Limulus polyphemus) populations are stable or declining. Spawning counts were conducted at sites from Casco Bay (southern Maine) to Frenchman’s Bay (downeast), to establish an index of relative abundance. Few (relatively) abundant populations remain in Maine at Middle Bay (Harpswell/Brunswick), Thomas Point (Brunswick), and in the Damariscotta River. Healthy but less abundant populations persist in the Bagaduce River (Brooksville/ Sedgwick) and in Taunton Bay (Hancock/Franklin/Sullivan).

An intensive tagging study has been conducted on Taunton Bay, which offers a natural population with …