Spectral fitting, shock layer modeling, and production of nitrogen oxides and excited nitrogen

An analysis was made of N2 emission from 8.72 MJ/kg shock layer at 2.54, 1.91, and 1.27 cm positions and vibrational state distributions, temperatures, and relative electronic state populations was obtained from data sets. Other recorded arc jet N2 and air spectral data were reviewed and NO emission characteristics were studied. A review of operational procedures of the DSMC code was made. Information on other appropriate codes and modifications, including ionization, were made as well as a determination of the applicability of codes reviewed to task requirement. A review was also made of computational procedures used in CFD codes of Li and other codes on JSC computers. An analysis was made of problems associated with integration of specific chemical kinetics applicable to task into CFD codes

Abundances of Baade's Window Giants from Keck/HIRES Spectra: I. Stellar Parameters and [Fe/H] Values

We present the first results of a new abundance survey of the Milky Way bulge based on Keck/HIRES spectra of 27 K-giants in the Baade's Window ($l = 1$, $b = -4$) field. The spectral data used in this study are of much higher resolution and signal-to-noise than previous optical studies of Galactic bulge stars. The [Fe/H] values of our stars, which range between -1.29 and $+0.51$, were used to recalibrate large low resolution surveys of bulge stars. Our best value for the mean [Fe/H] of the bulge is $-0.10 \pm 0.04$. This mean value is similar to the mean metallicity of the local disk and indicates that there cannot be a strong metallicity gradient inside the solar circle. The metallicity distribution of stars confirms that the bulge does not suffer from the so-called ``G-dwarf'' problem. This paper also details the new abundance techniques necessary to analyze very metal-rich K-giants, including a new Fe line list and regions of low blanketing for continuum identification.Comment: Accepted for publication in January 2006 Astrophysical Journal. Long tables 3--6 withheld to save space (electronic tables in journal paper). 53 pages, 10 figures, 9 table

Abundances and Kinematics of Field Halo and Disk Stars I: Observational Data and Abundance Analysis

We describe observations and abundance analysis of a high-resolution, high-S/N survey of 168 stars, most of which are metal-poor dwarfs. We follow a self-consistent LTE analysis technique to determine the stellar parameters and abundances, and estimate the effects of random and systematic uncertainties on the resulting abundances. Element-to-iron ratios are derived for key alpha, odd, Fe-peak, r- and s-process elements. Effects of Non-LTE on the analysis of Fe I lines are shown to be very small on the average. Spectroscopically determined surface gravities are derived that are generally close to those obtained from Hipparcos parallaxes.Comment: 41 pages, 7 Postscript figures. Accepted for publication in the A

Introduction to orbital flight planning (1)

This workbook is designed for students interested in space flight planning, who after training, may serve as flight planning aides. Routine flight planning activities requiring engineering-type calculations and analysis are covered. Practice exercises and brief instructions are given for the programming and use of the hand calculator as well as the calculation of position and velocity in the orbital plane. Calculation of relative orbital position is also covered with emphasis upon celestial coordinates and time measurement

Abundances in Stars from the Red Giant Branch Tip to the Near Main Sequence in M71: II. Iron Abundance

We present [Ffe/H] abundance results that involve a sample of stars with a wide range in luminosity from luminous giants to stars near the turnoff in a globular cluster. Our sample of 25 stars in M71 includes 10 giant stars more luminous than the RHB, 3 horizontal branch stars, 9 giant stars less luminous than the RHB, and 3 stars near the turnoff. We analyzed both Fe I and Fe II lines in high dispersion spectra observed with HIRES at the W. M. Keck Observatory. We find that the [Fe/H] abundances from both Fe I and Fe II lines agree with each other and with earlier determinations. Also the [Fe/H] obtained from Fe I and Fe II lines is constant within the rather small uncertainties for this group of stars over the full range in Teff and luminosity, suggesting that NLTE effects are negligible in our iron abundance determination. In this globular cluster, there is no difference among the mean [Fe/H] of giant stars located at or above the RHB, RHB stars, giant stars located below the RHB and stars near the turnoff.Comment: Minor changes to conform to version accepted for publication, with several new figures (Paper 2 of a pair

Examining Pre-Service Teacher Candidates’ Sources and Levels of Knowledge about Autism Spectrum Disorders

This study was designed to identify what pre-service teacher candidates knew about autism spectrum disorder (ASD) and how they had acquired that knowledge in order to design more effective preparation courses. Teacher candidates (N=87) from three teacher preparation programs completed questionnaires during, or prior to, their first special education course. The findings indicate a relationship between sources of knowledge about ASD and actual levels of knowledge. Based on the findings, the authors argue that there is a need for coursework that focuses on effective intervention strategies and utilizes direct opportunities for teacher candidates to work with students with ASD

Survey on the use of CAD-CAM technology by UK and Irish dental technicians

Statement of the problem Digital workflows (CAD/CAM) have been introduced in dentistry during recent years. No published information exists on dental technicians' use and reporting of this technology.Purpose The aim of this cross sectional survey was to identify the extent digital technology has infiltrated the workplace and to investigate the factors affecting the use of CAD-CAM technology by dental laboratory technicians within Ireland and the UK.Materials and methods A web-based questionnaire was composed (Opinio, Object Planet Inc. Oslo, Norway) and distributed to UK and Irish dental technicians. Answers to all questions were anonymous and grouped such that general information was gathered initially, followed by branching of the survey into two sections depending on whether or not the respondent worked with CAD-CAM technology. Results were compiled and statistical analysis (Fisher's Exact test, SPSS, IBM, Armonk, New York, USA) was performed in order to investigate any correlation between various demographic variables and the answers provided.Results The survey was distributed to 760 UK technicians and 77 Irish technicians. The total number of completed surveys was 105, which yielded a total response rate of 14%. Most technicians reported using some form of CAD/CAM aspect in the workflow, and this was more significant for technicians working in large laboratories. Most training received was company-led. Large laboratories were also significantly correlated with less outsourcing of CAD/CAM work and a change in dental material use leading to the increase of zirconia and the decrease of noble alloys. Dental technicians did not report any significant change in working relationships and staffing as a result of CAD/CAM incorporation. High initial investment cost was the most common reason quoted from non-users, along with the lack of such technology in their working environment

Hypoglossal schwannoma masquerading as a carotid body tumor.

Study Objective. To describe the clinical presentation, evaluation, and treatment of a hypoglossal schwannoma. Methods. We report an unusual case of a hypoglossal schwannoma presenting as a pulsatile level II neck mass at the bifurcation of the external and internal carotid arteries, mimicking a carotid body tumor. Radiologic findings are reviewed in detail. Results. A 59-year-old female presented to a tertiary care medical center with complaints of a pulsatile right-sided neck mass. An MRA of the neck was obtained demonstrating a 5 cm mass located at the carotid artery bifurcation and causing splaying of the internal and external carotids. Based on clinical presentation and imaging, a diagnosis of a carotid body tumor was conferred and the patient scheduled for excision. Intraoperatively, the mass was noted to arise from the hypoglossal nerve, remaining independent of the carotid artery. On histopathologic analysis, the mass was determined to be consistent with hypoglossal schwannoma. Conclusion. Though rare, the hypoglossal schwannoma should remain a consideration in the evaluation of a parapharyngeal space mass. As this report demonstrates, the clinical and radiologic presentation of a hypoglossal schwannoma may closely mimic that of the more common carotid body tumor

Improved Laboratory Transition Probabilities for Neutral Chromium and Re-determination of the Chromium Abundance for the Sun and Three Stars

Branching fraction measurements from Fourier transform spectra in conjunction with published radiative lifetimes are used to determine transition probabilities for 263 lines of neutral chromium. These laboratory values are employed to derive a new photospheric abundance for the Sun: log $\epsilon$(Cr I)$_{\odot}$ = 5.64$\pm$0.01 ($\sigma = 0.07$). These Cr I solar abundances do not exhibit any trends with line strength nor with excitation energy and there were no obvious indications of departures from LTE. In addition, oscillator strengths for singly-ionized chromium recently reported by the FERRUM Project are used to determine: log $\epsilon$(Cr II)$_{\odot}$ = 5.77$\pm$0.03 ($\sigma = 0.13$). Transition probability data are also applied to the spectra of three stars: HD 75732 (metal-rich dwarf), HD 140283 (metal-poor subgiant), and CS 22892-052 (metal-poor giant). In all of the selected stars, Cr I is found to be underabundant with respect to Cr II. The possible causes for this abundance discrepancy and apparent ionization imbalance are discussed.Comment: 44 pages, 6 figure

Analysis of Flow From Arc-Jet Spectra

Materials testing is carried out at the JSC Atmospheric Reentry Materials and Structures Facility. A flow diagnostics program is under development to characterize the energy distribution in arc-jet flows used to simulate atmospheric entry. Heat transfer to materials depends on flow properties which includes the composition of and energy distribution among the atoms, ions, molecules, and molecular ions which make up the flow. This project involves analysis of shock layer characteristics from the radiation emitted and experimentally collected from near the front of the shock to near the surface of the material. The analysis has yielded information on relative populations of neutral molecules and molecular ions within the layer. In determining non-equilibrium temperatures within the layer, some insight into the spectral constants used to compute radiative emission has been gained