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91.
92.
J.-E. Solheim R. Østensen R. Silvotti U. Heber 《Astrophysics and Space Science》2004,291(3-4):419-426
A search program for pulsating sdBs was conducted with the Nordic Optical Telescope in the years 1999–2001. Possible candidates were selected from the HS, HE and PG surveys. In total 10 pulsators were found, some quite bright. In addition one more was found from a small SDSS sample observed in Oct. 2002. 相似文献
93.
94.
JØrgen Christensen-Dalsgaard 《Solar physics》2004,220(2):137-168
The physics of solar and stellar oscillations determines their observable properties: frequencies, amplitudes, lifetimes,
line asymmetries and phase relations. In the solar case these quantities have been measured, often with high precision, and
much has been learned about the properties of the solar interior, and the properties of the oscillations. With recent advances
in observational techniques, such seismic investigations are now being extended to solar-like oscillations in distant stars.
I provide a brief overview of the basic properties of stellar oscillations, and of the information about stellar properties
that may be inferred from them, concentrating mostly on the low-degree modes for which information may be expected for distant
stars. In addition, I consider the current state of investigations of solar-like oscillations in other stars, and the prospects
for an improved understanding of the physics of such oscillations. 相似文献
95.
Hedman JE Rüdel H Gercken J Bergek S Strand J Quack M Appelberg M Förlin L Tuvikene A Bignert A 《Marine pollution bulletin》2011,62(10):2015-2029
The implementation of the EU Marine Strategy Framework Directive necessitates the development of common criteria and methodological standards for marine environmental monitoring and assessment across Europe. Eelpout (Zoarces viviparus) is proposed as a key indicator organism in the Baltic and North Sea regions. This benthic fish species is widely used in ecotoxicological studies and as a bioindicator of local pollution due to its stationary behavior. Eelpout is included in the environmental monitoring program of several Baltic States, covering both chemical and biological effects measurements, and samples have been archived in environmental specimen banks for >15 years. A method for evaluating the frequency of larval aberrations has been suggested as a standardized assessment tool. The large scientific knowledge-base and considerable experience of long-term chemical and biological effects monitoring and specimen banking, make eelpout a suitable species for the assessment of Good Environmental Status in the Baltic and North Seas. 相似文献
96.
97.
HENNING MØRCH M.Sc. 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):89-92
Mørch, Henning: Population and resources in two types of rural landscape—Denmark 1860, 1900, and 1960. Geografisk Tidsskrift 80: 88–92. Copenhagen, June 1980. An investigation on the basis of simple, linear regression of the relationship between size of population and physical resources in two types of landscape—moraine and outwash plain—Denmark 1860–1960. 相似文献
98.
Advances in search and rescue at sea 总被引:2,自引:0,他引:2
Øyvind Breivik Arthur Addoms Allen Christophe Maisondieu Michel Olagnon 《Ocean Dynamics》2013,63(1):83-88
A topical collection on “Advances in Search and Rescue at Sea” has appeared in recent issues of Ocean Dynamics following the latest in a series of workshops on “Technologies for Search and Rescue and other Emergency Marine Operations” (2004, 2006, 2008, and 2011), hosted by IFREMER in Brest, France. Here, we give a brief overview of the history of search and rescue at sea before we summarize the main results of the papers that have appeared in the topical collection. 相似文献
99.
The highly seasonal Norwegian cod fisheries give rise to problems downstream in the value chain and the authorities have introduced several schemes to counter the strong incentives for seasonal harvesting. This paper studies how the trawler delivery obligation (TDO) regime influences aspects of the harvesting pattern, focusing on the temporal and geographic distribution of landings. The analysis shows that the trawlers as a group have far less seasonal variations in their cod landings compared to the coastal fleet. While the Norwegian fleet lands about 75% during the first half-year, the corresponding share for trawlers is about 50%. Contrary to the initial hypothesis, the independent trawlers fished the most off-season; about 57% of their total landings. Trawlers controlled by vertically integrated firms landed considerably less (about 45%) and independently owned trawlers with landing obligations fell between these two strategic groups (about 50%). Vertically integrated vessels have a higher fulfilment of their landing obligations than the independently owned. The differences between the strategic groups are relatively high, at 68% vs. 38%. These results indicate that delivery obligations alone are not sufficient to provide control over the geographic distribution. 相似文献
100.
Øyvind Breivik Arthur A. Allen Christophe Maisondieu Jens-Christian Roth Bertrand Forest 《Ocean Dynamics》2012,62(5):741-752
The leeway of 20-ft containers in typical distress conditions is established through field experiments in a Norwegian fjord
and in open-ocean conditions off the coast of France with a wind speed ranging from calm to 14 m s−1. The experimental setup is described in detail, and certain recommendations were given for experiments on objects of this
size. The results are compared with the leeway of a scaled-down container before the full set of measured leeway characteristics
are compared with a semianalytical model of immersed containers. Our results are broadly consistent with the semianalytical
model, but the model is found to be sensitive to choice of drag coefficient and makes no estimate of the crosswind leeway
of containers. We extend the results from the semianalytical immersion model by extrapolating the observed leeway divergence
and estimates of the experimental uncertainty to various realistic immersion levels. The sensitivity of these leeway estimates
at different immersion levels are tested using a stochastic trajectory model. Search areas are found to be sensitive to the
exact immersion levels, the choice of drag coefficient, and somewhat less sensitive to the inclusion of leeway divergence.
We further compare the search areas, thus, found with a range of trajectories estimated using the semianalytical model with
only perturbations to the immersion level. We find that the search areas calculated without estimates of crosswind leeway
and its uncertainty will grossly underestimate the rate of expansion of the search areas. We recommend that stochastic trajectory
models of container drift should account for these uncertainties by generating search areas for different immersion levels
and with the uncertainties in crosswind and downwind leeway reported from our field experiments. 相似文献