46,596 research outputs found
Feasibility of Kevlar 49/PMR-15 Polyimide for High Temperature Applications
Kevlar 49 aramid organic fiber reinforced PMR-15 polyimide laminates were characterized to determine the applicability of the material to high temperature aerospace structures. Kevlar 49/3501-6 epoxy laminates were fabricated and characterized for comparison with the Kevlar 49/PMR-15 polyimide material. Flexural strengths and moduli and interlaminar shear strengths were determined from 75 F to 600 F for the PMR-15 and from 75 F to 450 F for the Kevlar/3501-6 epoxy material. The effects of hydrothermal and long-term elevated temperature exposures on the flexural strengths and moduli and the interlaminar shear strengths were also studied
The impact of information and communication technology on family carers of older people and professionals in Sweden
Government policy in Sweden, as in other developed countries, pays increasing attention as to how best to support the family carers of older people. New and innovative means of support, such as information and communication technology, are emerging. This paper explores the perceived benefits of, and barriers to, information technology as a means of supporting family carers of older people.
Following a brief overview of the care-giving literature, with particular reference to the Swedish context, interview and questionnaire data collected from 34 families who took part in the Swedish ACTION project are used to explore the role of user-friendly information and communication technology to inform and enable family carers of older people to exercise choice, to care more effectively and to work in partnership with professionals. Interview data from two groups of professionals that utilised ACTION are also examined to throw light on its potential benefits for both carers and professionals. Consideration is given to the barriers to using information technology, and to identifying those carers most likely to benefit. Areas for further development are the need for practitioners' education and a wider range of programmes to address carers' diverse needs. Clearly, lessons learned from the Swedish project have wider relevance, given that new forms of support are being developed in most technically advanced countries
MASSCLEAN - MASSive CLuster Evolution and ANalysis Package - Description, Tests, and Results
MASSCLEAN is a new, sophisticated and robust stellar cluster image and
photometry simulation package. This package is able to create color-magnitude
diagrams and standard FITS images in any of the traditional optical and
near-infrared bands based on cluster characteristics input by the user,
including but not limited to distance, age, mass, radius and extinction. At the
limit of very distant, unresolved clusters, we have checked the integrated
colors created in MASSCLEAN against those from other simple stellar population
(SSP) models with consistent results. Because the algorithm populates the
cluster with a discrete number of tenable stars, it can be used as part of a
Monte Carlo Method to derive the probabilistic range of characteristics
(integrated colors, for example) consistent with a given cluster mass and age.
We present the first ever mass dependent integrated colors as a function of
age, derived from over 100,000 Monte Carlo runs, which can be used to improve
the current age determination methods for stellar clusters.Comment: 4 pages, 5 figures, Proceedings International Astronomical Union
Symposium No. 266, Star Clusters - Basic Galactic Building Blocks throughout
Time and Space, Editors: Richard de Grijs & Jacques R. D. Lepin
Infrared spectroscopic variability of Cygnus X-3 in outburst and quiescence
We present four epochs of high-resolution infrared spectroscopy of the
peculiar X-ray binary Cygnus X-3. The observations cover quiescent, small
flaring and outburst states of the system as defined by radio and X-ray
monitoring. The underlying infrared spectrum of the source, as observed during
radio and X-ray quiescence and small flaring states, is one of broad, weak HeII
and NV emission. Spectral variability in this state is dominated by modulation
at the 4.8 hr orbital period of the system. H-band spectra confirm the
significant hydrogen depletion of the mass donor. The closest spectral match to
the quiescent infrared spectrum of Cyg X-3 is an early-type WN Wolf-Rayet star.
In outburst, the infrared spectrum is dramatically different, with the
appearance of very strong twin-peaked HeI emission displaying both day-to-day
variability and V(iolet)/R(ed) variations with orbital phase. The most likely
explanation appears to be an enhanced stellar wind from the companion. Thus
X-ray and radio outbursts in this system are likely to originate in
mass-transfer, and not disc, instabilities, and the lengthening of the orbital
period will not be smooth but will be accelerated during these outbursts.
Furthermore, the appearance of these lines is suggestive of an asymmetric
emitting region. We propose that the wind in Cyg X-3 is significantly flattened
in the plane of the binary orbit. This may explain the observed twin-peaked HeI
features as well as reconciling a massive Wolf-Rayet secondary with the
relatively small optical depth to X-rays, if the disc wind is inclined at some
angle to the line of sight.Comment: 13 pages, 7 figures. Accepted for publication in MNRA
Housing and Support Needs of Older People with Visual Impairment - experiences and challenges
NGC 1058: Gas motions in an extended, quiescent spiral disk
Researchers investigate in detail the motion of gas in the galaxy NGC 1058 using the very large array (VLA) to map the emission in the 21-cm line. This galaxy is so nearly face-on that the contribution to the line width due to the variation of the rotational velocity across the D-array beam is small compared with the random z-motion of the gas. Researchers confirm results of earlier studies (Lewis 1987, A. and A. Suppl., 63, 515; van der Kruit and Shostak 1984, A. and A., 134, 258) of the galaxy's total neutral hydrogen (HI) and kinematics, including the fact that the rotation curve drops faster than Keplerian at the outer edge of the disk, which is interpreted as a fortuitous twist of the plane of rotation in the outer disk. However, their very high velocity resolution (2.58 km s(exp -1) after Hanning smoothing) coupled with good spatial resolution, allows researchers to measure more accurately the line width, and even to some extent its shape, throughout the disk. One of the most interesting results of this study is the remarkable constancy of the line width in the outer disk. From radius 90 to 210 seconds the Gaussian velocity dispersion (sigma sub nu) of the 21-cm line has a mean value of 5.7 km s(exp -1) (after correcting for the spectral resolution) with a dispersion of less than 0.9 km s(exp -1) (after correcting for the spectral resolution) with a dispersion of less than 0.9 km s(exp -1). Translating this directly into a kinetic temperature (Doppler temperature): T sub Dopp equals 121K (sigma sub mu exp 2/(km s(exp -1) (exp 2) gives 4000 K, with a dispersion of less than 1500 K over the outer disk. This constancy is observed even when comparing the spiral arms versus inter-arm regions, which in the radius range from 100 to 150 seconds the surface density modulates (defined as the ratio N sub peak -N sub trough/N sub peak + N sub trough) from 0.5 to 0.25 in the range 150 to 200 seconds
Working Effectively With Employees who Have Sustained a Brain Injury
This brochure on individuals who have sustained a brain injury and the Americans with Disabilities Act (ADA) is one of a series on human resources practices and workplace accommodations for persons with disabilities edited by Susanne M. Bruyère, Ph.D., CRC, SPHR, Director, Program on Employment and Disability, School of Industrial and Labor Relations – Extension Division, Cornell University. It was updated in June, 2000 by Stephanie Hanson, Ph.D., College of Health Professions, University of Florida. The original as written by Thomas P. Golden, M.S., Program on Employment and Disability, Cornell University. Cornell University was funded in the early 1990’s by the U.S. Department of Education National Institute on Disability and Rehabilitation Research as a National Materials Development Project on the employment provisions (Title I) of the ADA (Grant #H133D10155). These updates, and the development of new brochures, have been funded by Cornell’s Program on Employment and Disability, the Pacific Disability and Business Technical Assistance Center, and other supporters
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