45,801 research outputs found
ERTS wideband tape recorder
The ERTS video bandwith tape recorder uses a rotary head to run the tape in transverse mode; the head wheel gives a head-to-tape surface speed of nearly 5080 centimeter per second. The electronics unit handles 15 megabit per second rate with a bit-error rate of 0.00001. An operational unit onboard ERTS A returned images from the 85 to 90 percent of the earth that are not available in real time
Reconciling visions and realities of virtual working: findings from the UK chemicals industry
The emergence of advanced technologies such as Grid computing will, some suggest, allow the final realisation of visions of virtual organisations. This will, according to its advocates, have entirely positive impacts, creating communities of experts, increasing flexibility, reducing the need for travel and making communications more efficient by crossing boundaries of time and space. Such predictions about future patterns of virtual working are, unfortunately, rarely grounded in real working practices, and often neglect to account for both the rich and varied interpretations that may exist of what constitutes virtual working and the constraints and concerns of those who would do it. This chapter gives attention to the consequences of different views over what virtuality might mean in practice and, in particular, considers virtuality in relation to customer and supplier relationships in a competitive and commercial context. The discussion is based upon a three year study that investigated contrasting visions of what was technically feasible and might be organisationally desirable in the UK Chemicals industry. Through interviews with managers and staff of companies both large and small that research provided insights into the different meanings that organisations attribute to the virtuality of work and to the acceptability of potential implementations of a middleware technology. It was found that interpretations of virtuality amongst the potential users and participants were strongly influenced by established work practices and by previous experiences of relationships-at-a-distance with suppliers and customers. There was a sharp contrast with the enthusiastic visions of virtual working that were already being encapsulated in the middleware by the technical developers; visions of internet-only interaction were perceived as rigid, alienating from well-established ways of working with suppliers and customers and unworkable. In this chapter we shall capture these differences by making a distinction amongst compet
Isotopic Biogeochemistry
An overview is provided of the biogeochemical research. The funding, productivity, personnel and facilities are reviewed. Some of the technical areas covered are: carbon isotopic records; isotopic studies of banded iron formations; isotope effects in microbial systems; studies of organic compounds in ancient sediments; and development in isotopic geochemistry and analysis
Out-of-School Immigrant Youth
Describes the population of out-of-school immigrant youth in California and the subset of this group served by California's Migrant Education Program. Suggests ways to target services, improve future data collection, and enhance program organization
The Central Valley at a Crossroads: Migration and Its Implications
Examines recent trends in domestic and international migration flows, population growth, and changes in the region's socioeconomic profile. Looks at policy strategies used by each valley subregion to address challenges presented by recent migration
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Developing web services in a computational grid environment
Grid and Web services are both hot topics today. In this paper, we will present some ongoing work and planned future work at the Cambridge eScience Centre. After an introduction to these technologies in the context of Grid applications development, we describe two use-cases: a database
of results in computational fluid dynamics (CFD) and a small computational Grid for aircraft engineering design.
As Grid services are moving towards Web services, we continue
to make use of the Globus Toolkit v2.4 (GT2.4), without
adopting the Open Grid Services Architecture (OGSA)
wholesale. In our scenario, GT2.4 integrates distributed
computing resources including HPC and clusters while Web
services wrap the scientific code as a service.Proceedings of the IEEE International Conference on Services Computing, Shanghai, September 200
Organic barley producers' desired qualities for crop improvement
Barley fits well into many different organic farming systems. It can be grown as either a winter or spring annual crop in many temperate regions. Barley can be used for food, malting, or animal feed, providing growers with diverse marketing opportunities. Despite its advantages, many organic farmers in the USA have not adopted barley as a regular crop in their rotation. Researchers surveyed organic barley producers to discover what they considered to be the main obstacles to growing barley. The primary obstacles identified were limited markets and price. Breeding and development of high-quality barley suitable for organic systems and specialty markets may be a way to expand markets and secure a better price. Farmers identified yield as the most important agronomic trait of interest, but other traits such as nutritional quality were also highly ranked. Naked (hull-less) barley bred for multi-use quality is a possible alternative that allows organic farmers to sell into multiple markets. Most respondents expressed interest in the development of such varieties suitable for organic farming conditions. The researchers conducted follow-up interviews to obtain detailed information on how barley is used in organic farming systems, production practices, costs of production, and what traits farmers would like to see breeders focus on
Improving Barley for Organic Producers: What Do Organic Producers Want?
Researchers surveyed organic barley producers in order to find out how many acres they are growing, what varieties they grow, what markets they are growing barley for, whether they receive a price premium for organic barley, whether they are growing or would be interested in growing multi-use naked barley, what production challenges they face, and what traits they would like to see improved
Using Lyman-alpha to detect galaxies that leak Lyman continuum
We propose to infer ionising continuum leaking properties of galaxies by
looking at their Lyman-alpha line profiles. We carry out Lyman-alpha radiation
transfer calculations in two models of HII regions which are porous to ionising
continuum escape: 1) the so-called "density bounded" media, in which massive
stars produce enough ionising photons to keep the surrounding interstellar
medium transparent to the ionising continuum, i.e almost totally ionised, and
2) "riddled ionisation-bounded" media, surrounded by neutral interstellar
medium, but with holes, i.e. with a covering factor lower than unity. The
Lyman-alpha spectra emergent from these configurations have distinctive
features: 1) a "classical" asymmetric redshifted profile in the first case, but
with a small shift of the maximum of the profile compare to the systemic
redshift (Vpeak < 150 km/s); 2) a main peak at the systemic redshift in the
second case (Vpeak = 0 km/s), with, as a consequence, a non-zero Lyman-alpha
flux bluewards the systemic redshift. Assuming that in a galaxy leaking
ionising photons, the Lyman-alpha component emerging from the leaking star
cluster(s) dominates the total Lyman-alpha spectrum, the Lyman-alpha shape may
be used as a pre-selection tool to detect Lyman continuum (LyC) leaking
galaxies, in objects with well determined systemic redshift, and high spectral
resolution Lyman-alpha spectra (R >= 4000). The examination of a sample of 10
local starbursts with high resolution HST-COS Lyman-alpha spectra and known in
the literature as LyC leakers or leaking candidates, corroborates our
predictions. Observations of Lyman-alpha profiles at high resolution should
show definite signatures revealing the escape of Lyman continuum photons from
star-forming galaxies.Comment: A&A in pres
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