27,257 research outputs found
What is the primary beam response of an interferometer with unequal elements?
The EVN stations encompass elements with a range of diameters, even including
an interferometer (the Westerbork Telescope, with up to 14 elements used
together as a tied array). In combination, the various station pairs will each
produce their own primary beam envelopes, with which the interferometer pattern
is modulated. People sometimes forget that in the case of unequal elements,
this combined primary beam envelope is different from the beam of each element
separately. The reason for this is reviewed, the results for a number of
station pairs are summarized, and some of the practical consequences are
discussed. The increased interest in wide-field applications, as illustrated by
several recent results, underlines the need for a proper determination of the
interferometer beam envelope.Comment: 2 pages. no figures. Proceedings of the 7th European VLBI Network
Symposium held in Toledo, Spain on October 12-15, 2004. Editors: R.
Bachiller, F. Colomer, J.-F. Desmurs, P. de Vicente (Observatorio Astronomico
Nacional), p. 273-274. Needs evn2004.cl
Symplectic reduction of quasi-morphisms and quasi-states
We prove that quasi-morphisms and quasi-states on a closed integral
symplectic manifold descend under symplectic reduction to symplectic hyperplane
sections. Along the way we show that quasi-morphisms that arise from spectral
invariants are the Calabi homomorphism when restricted to Hamiltonians
supported on stably displaceable sets.Comment: 20 pages; v2: added remarks and updated references, to appear in
Journal of Symplectic Geometr
The evolution of young stellar object disks and their environment
The main efforts were directed towards determining the frequency of disk occurrence and the timescales for disk evolution for solar-type and intermediate mass stars. The results of the investigation showed that optically thick disks are accretion disks. The projected accomplishments are also discussed
The properties and environment of primitive solar nebulae as deduced from observations of solar-type pre-main sequence stars
The following topics were discussed: (1) current observation evidence for the presence of circumstellar disks associated with solar type pre-main sequence (PMS) stars; (2) the properties of such disks; and (3) the disk environment
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Asian Varieties of Service Capitalism?
There is currently only limited empirical research and theoretical conceptualisation of the role of knowledge-intensive business services (KIBS) in the economies of Asia within economic geography or elsewhere in the wider social scientific literature. This paper argues that existing theoretical understandings of KIBS are inadequate to conceptualise the nature of ongoing KIBS development in Asian economies – both emerging and mature – and seeks to address this absence by developing a theoretical framework that draws on a range of existing theoretical approaches within and beyond economic geography. To do this, it proposes the concept of ‘service capitalism’, developed from work concerned with varieties of capitalism (VoC), variegated capitalism and advanced service industries. The paper elaborates its theoretical argument by presenting research into two forms of Asian service capitalism through two case studies examining respectively the specific nature of Japanese KIBS and the development of KIBS in China. Using the case studies, it demonstrates how service industry development in both these Asian economies exhibits distinctive characteristics that are a consequence of both local institutional, corporate, and socio-cultural contexts but are also interconnected the wider global economy in complex ways. The paper thus presents a significant and disruptive challenge to existing theories of KIBS development as based on the western experience, and contemporary deployments of the varieties of capitalism and variegated capitalism approaches
Study of abundance analysis of stars in the spectral range B5 through G2 Semiannual progress report, 1 Jun. - 30 Nov. 1969
Research in helium abundance, blue stragglers, and stars in contraction phas
Model atmospheres for RR Lyrae stars
Model atmospheres for RR Lyrae star
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