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141.
Bruno Benthien 《GeoJournal》1984,9(1):59-63
This paper is a short report on concepts, methods, definitions and fields of geographical research into tourism and recreation in the GDR. Main centres of research are the Dresden College of Transport, the Dresden College of Education and the Geography sections of the Universities of Berlin and Greifswald. After the Dresden Conference on Geography of Tourism in 1965 the Greifswald Geographical Symposium on Recreational Geography in 1978 was the second decisive GDR conference. Than it became quite clear that the emphasis in research has shifted from tourism to territorial problems of recreation, primarily the various forms of outdoor recreation. The theoretical approach is shown as Greifswald model of recreational geography (Fig 1). 相似文献
142.
Two approaches are followed to estimate the fit between ‘observations’ and the results obtained with different numerical models within the frame of the Tidal Flow Forum exercise. The first approach (i.e. the computation of the RMS errors on the timeseries for a specific day) is shown to be insufficient because the RMS error computed over a short period of time is strongly dependent on the selected test period. Such RMS values are significant if and only if they are computed over a sufficiently long period of time, T. Hence, the model validation must be done on the basis of the results of long term simulations. The limit of the RMS values as T becomes arbitrarily large is related to the maximum error made on each constituent. Those maximum errors are easily calculated from the harmonic constants (computed versus observed) of the constituents. The results of the calculation of the maximum errors indicate that the M2, S2, N2 and M4 components are the largest contributors to the overall error for the area under consideration. On the basis of maximum errors, the TFF results obtained so far are almost of the same order of accuracy. The errors affecting the TFF results are not much larger than those affecting most reported results of similar models used in similar applications 相似文献
143.
In this paper we describe a new computing system array, designed, built and now used at the Space Astrophysics and Planetary Institute (IAPS) in Rome, Italy, for the INTEGRAL Space Observatory scientific data analysis. This new system has become necessary in order to reduce the processing time of the INTEGRAL data accumulated during the more than 9 years of in-orbit operation. In order to fulfill the scientific data analysis requirements with a moderately limited investment the starting approach has been to use a ??cluster?? array of commercial quad-CPU computers, featuring the extremely large scientific and calibration data archive on line. 相似文献
144.
Bruno P. Besser Mikhail I. Pudovkin Valentina V. Lebedeva Svetlana A. Zaitseva Claudia-Veronika Meister 《Astrophysics and Space Science》2000,274(1-2):399-405
Variations of the magnetic field and plasma parameters across the Earth's magnetosheath are calculated for an anisotropic
plasma in the Chew-Goldberger-Low approximation. Additionally, proton pitch-angle diffusion is taken into account as the energy
transfer mechanism between the direction perpendicular and parallel to the magnetic field. We discuss the main characteristics
of the magnetic barrier for different temperature relaxation times and their dependence on the interplanetary magnetic field
orientation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
145.
146.
147.
We investigate the properties of intermittency of magnetic turbulence by using magnetic field data collected by the Helios spacecraft in the inner heliosphere. Clear scaling laws for magnetic structure functions are visible in periods where the velocity of the bulk plasma is low. Within these periods we found that intermittency of magnetic turbulence is high with respect to velocity field. A comparison with fluid flows where passive scalars are more intermittent than velocity, yields to consider the magnetic field like a “passive vector”. 相似文献
148.
Accretion, feedback and galaxy bimodality: a comparison of the GalICS semi-analytic model and cosmological SPH simulations 总被引:1,自引:0,他引:1
149.
Jordan S. Oestreicher Karina Benessaiah Maria C. Ruiz-Jaen Sean Sloan Kate Turner Johanne Pelletier Bruno Guay Kathryn E. Clark Dominique G. Roche Manfred Meiners Catherine Potvin 《Global Environmental Change》2009,19(2):279-291
Reducing greenhouse gas emissions from deforestation and forest degradation (REDD) is likely to be central to a post-Kyoto climate change mitigation agreement. As such, identifying conditions and factors that will shape the success or failure of a reduced deforestation scheme will provide important insights for policy planning. Given that protected areas (PAs) are a cornerstone in forest conservation, we draw on interviews and secondary data to analyze the effects of available PA resources, governance ability, the level of community involvement, and provincial deforestation rates on land-cover change in nine PAs in Panama. Our results illustrate that coupling surveillance measures with greater funding and strong governance are paramount to reducing deforestation. Alone, however, these factors are insufficient for forest protection. We argue that conservation approaches that complement effective surveillance with community participation and equitable benefit sharing will address the wider issues of leakage and permanence. 相似文献
150.
Bruno Bézard André Marten Jean Paul Baluteau Daniel Gautier Jean-Marie Flaud Claude Camy-Peyret 《Icarus》1983,55(2):259-271
The influence of hydrogen sulfide, a still-undetected key molecule for the Jovian atmospheric chemistry in the infrared spectrum, was investigated. Synthetic spectra including various vertical distribution profiles of H2S have been computed and compared with observational data for Jupiter in the 2- to 15-cm?1 and 1160- to 1200-cm?1 spectral ranges. No firm conclusion about the presence of H2S can be drawn from the latter spectral region because of large uncertainties in gaseous opacities. In the microwave range, H2S is found to be a possible candidate to explain the measurements. Constraints to its vertical distribution which would imply a significant supersaturation in the troposphere are derived. Physical and chemical processes involving H2S in the atmosphere are discussed in the light of this hypothesis. 相似文献