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61.
Max K. Wallis 《Planetary and Space Science》1975,23(3):419-430
Interstellar gas streaming through the solar system undergoes both elastic collisions with solar wind ions and destructive, ionizing processes. The Boltzmann equation is set up, with linear Fokker-Planck terms describing the glancing elastic collisions. Solutions combining the dynamical effects of the central force field and the diffusion in velocity space are derived, appropriate to cool gas.For the He component of the streaming gas, if initially at 100 K, the collisional heating dominates inside 2 a.u. upstream and 5 a.u. downstream. A modified formula is given for the density in the downstream wake, as enhanced by gravitational focussing. Calculations of the helium resonant radiation backscatter require substantial modification. 相似文献
62.
Optimization of mooring observations in Northern Bering Sea 总被引:1,自引:0,他引:1
The problem of the optimal sampling strategy for moored current velocity observations in the Northern Bering Sea is addressed. We analyze dynamically induced correlations in the North Bering Sea currents and conduct their sensitivity analysis to optimize positions of a limited number of moorings. Optimization of the sampling strategy is performed with respect to robustness of the reconstruction of the North Bering Sea circulation with a particular emphasis on the accurate monitoring of the mean Bering Strait transport. Computations reveal four major regions in the North Bering Sea basin that are highly correlated with the Bering Strait transport. Apart from the regions within the Bering Strait itself, they include the Anadyr Strait and a region 100 km south of the Cape of Prince of Wales. Results of the sensitivity analysis are tested in the framework of twin data experiments with the quasi-stationary and oscillatory background circulations. 相似文献
63.
64.
Max Spolaor Duncan A. Forbes George K. T. Hau Robert N. Proctor Sarah Brough 《Monthly notices of the Royal Astronomical Society》2008,385(2):667-674
This is the first paper of a series focused on investigating the star formation and evolutionary history of the two early-type galaxies NGC 1407 and NGC 1400. They are the two brightest galaxies of the NGC 1407 (or Eridanus-A) group, one of the 60 groups studied as part of the Group Evolution Multi-wavelength Study.
Here, we present new high signal-to-noise ratio long-slit spectroscopic data obtained at the ESO 3.6-m telescope and high-resolution multiband imaging data from the Hubble Space Telescope /Advanced Camera for Surveys and wide-field imaging from Subaru Suprime-Cam. We spatially resolved integrated spectra out to ∼0.6 (NGC 1407) and ∼1.3 (NGC 1400) effective radii. The radial profiles of the kinematic parameters vrot , σ, h 3 and h 4 are measured. The surface brightness profiles are fitted to different galaxy light models and the colour distributions analysed. The multiband images are modelled to derive isophotal shape parameters and residual galaxy images. The parameters from the surface brightness profile fitting are used to estimate the mass of the possible central supermassive black hole in NGC 1407. The galaxies are found to be rotationally supported and to have a flat core in the surface brightness profiles. Elliptical isophotes are observed at all radii and no fine structures are detected in the residual galaxy images. From our results, we can also discard a possible interaction between NGC 1400, NGC 1407 and the group intergalactic medium. We estimate a mass of ∼1.03 × 109 M⊙ for the supermassive black hole in NGC 1407 galaxy. 相似文献
Here, we present new high signal-to-noise ratio long-slit spectroscopic data obtained at the ESO 3.6-m telescope and high-resolution multiband imaging data from the Hubble Space Telescope /Advanced Camera for Surveys and wide-field imaging from Subaru Suprime-Cam. We spatially resolved integrated spectra out to ∼0.6 (NGC 1407) and ∼1.3 (NGC 1400) effective radii. The radial profiles of the kinematic parameters v
65.
Max Eriksson 《社会与自然资源》2017,30(11):1374-1388
Attitudes towards wolf policy are likely to be driven by perceived differences in political power between urban and rural groups. Using Swedish survey data collected in 2014 and structural equation modeling, I evaluated the effects of political alienation. Political alienation mediated the effect of having an urban or rural place of residence on attitudes towards wolf policy. Politically alienated individuals also preferred more extreme policy options than other respondents, while being less likely to approve of the current wolf policy in Sweden. These findings suggest that political alienation drives attitude polarization in wolf related social conflicts. Awareness of these underlying power asymmetries could possibly increase both policy legitimacy and management efficiency. This highlights the importance of accounting for social context in relation to policy-making and conservation efforts related to wolves. 相似文献
66.
Landowner Attitudes Toward Conservation Easements: Balancing the Private and Public Interest in Land
Private land conservation provides an opportunity to address problems of habitat fragmentation and biodiversity loss caused by an increase in the development and parcelization of private land. Conservation easements (CEs) are used to protect significant natural qualities of private land. In this study, we explore landowner attitudes toward CEs through the implementation of a mixed-mode survey to private landowners in the Whychus Creek Watershed (Deschutes County, Oregon). The results of an exploratory factor analysis suggest there are two dimensions to landowner attitudes toward CEs, an internal dimension and an external dimension. We found that positive external attitudes are primarily influenced by environmental beliefs, whereas positive internal attitudes are influenced by a suite of factors, including financial beliefs and perceived risk to private ownership. Awareness of CEs may also play a role in attitude development. Through this research, we argue that CEs may be beneficial in reintegrating the public good into private property. 相似文献
67.
Prof. Dr. Max Müller 《Pure and Applied Geophysics》1950,17(1-2):54-63
Zusammenfassung Es wird eine Induktionsimpulsmethode beschrieben, welche sich auf die Messung dielektrischer Dispersionsphänomene gründet, und welche einen direkten Nachweis des Petroleums auf Tiefen von über 2000 m ermöglicht. Durch Variation der Anfachungsbedingungen kann man selektive Reaktionswirkungen erzielen.
Summary An induction pulse method is described, based upon the measurement of a dielectric dispersion phenomenon. This method opens the possibility of a direct and selective reaction of the petroleum at a depth of more than 6000 feet. Hereby the selective reaction is based upon the variation of the exciting conditions.相似文献
68.
Summary Data are given of the vertical distribution of temperature, conductivity and alkalinity of an eutrophic lake (Rotsee near
Lucerne) measured at short intervals during the summer stratification. We were able to prove in a limited measure only the
expected day's periodicity from the conductivity of the CO2-assimilation of the phytoplankton. We found pronounced internal ‘seiches’ in the hypolimnion; their mathematical interpretation
is given only in the order of size.Rodhe's diagram andNümann's method make it possible to determine quantitative relations; from the chemical point of view the lake (depth 16,5 m) shows
a four-layered type during the summer.
相似文献
69.
Max Richter 《International Journal of Earth Sciences》1937,28(1-2):135-136
Ohne Zusammenfassung 相似文献
70.
Max Semper 《International Journal of Earth Sciences》1911,2(5-6):263-277
Ohne Zusammenfassung 相似文献