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81.
Katherine Witt Helen Ross Sylvie Shaw Natalie Jones David Rissik Breanna Pinner 《社会与自然资源》2019,32(6):638-656
In Integrated Catchment (or Watershed) Management, the impacts of upstream conditions and actions on downstream environments and people is a key issue. Knowing upstream people’s values towards waterways is, therefore, important for community engagement and the development of publicly acceptable management approaches. This qualitative study applies Kellert’s framework of relational values to explore the types and diversity of people’s values towards the upper catchments of South East Queensland, Australia, and tests the “universality” of Kellert’s framework. We found the full range of values identified by Kellert with some variations and elaborations in content. People living, working, and enjoying recreation in the upper catchments have affection for their local waterways and a moral inclination to protect them. This extends our understanding of how people value these waterways, which is more often depicted in terms of utilitarian and economic value. The findings provide managers with new opportunities for engaging with local communities and waterway users. 相似文献
82.
83.
Vincent Jaillot Sylvie Servigne Gilles Gesquière 《International journal of geographical information science》2020,34(10):2030-2052
ABSTRACT Studying and planning urban evolution is essential for understanding the past and designing the cities of the future and can be facilitated by providing means for sharing, visualizing, and navigating in cities, on the web, in space and in time. Standard formats, methods, and tools exist for visualizing large-scale 3D cities on the web. In this paper, we go further by integrating the temporal dimension of cities in geospatial web delivery standard formats. In doing so, we enable interactive visualization of large-scale time-evolving 3D city models on the web. A key characteristic of this paper lies in the proposed four-step generic approach. First, we design a generic conceptual model of standard formats for delivering 3D cities on the web. Then, we formalize and integrate the temporal dimension of cities into this generic conceptual model. Following which, we specify the conceptual model in the 3D Tiles standard at logical and technical specification levels, resulting in an extension of 3D Tiles for delivering time-evolving 3D city models on the web. Finally, we propose an open-source implementation, experiments, and an evaluation of the propositions and visualization rules. We also provide access to reproducibility notes allowing researchers to replicate all the experiments. 相似文献
84.
Maryline Moulin Daniel Aslanian Mikael Evain Anglique Leprêtre Philippe Schnurle Fanny Verrier Joseph Thompson Philippe De Clarens Sylvie Leroy Nuno Dias 《地学学报》2020,32(3):205-214
The Natal Valley, offshore Mozambique, is a key area for understanding the evolution of East Gondwana. Within the scope of the integrated multidisciplinary PAMELA project, we present new wide‐angle seismic data and interpretations, which considerably alter Geoscience paradigms. These data reveal the presence of a 30‐km‐thick crust that we argue to be of continental nature. This falsifies all the most recent palaeo‐reconstructions of the Gondwana. This 30‐km‐thick continental crust 1,000 m below sea level implies a complex history with probable intrusions of mantle‐derived melts in the lower crust, connected to several occurrences of magmatism, which seems to evidence the crucial role of the lower continental crust in passive margin genesis. 相似文献
85.
Distribution and chronology of Pleistocene permafrost features in France: Database and first results
Pascal Bertran Eric Andrieux Pierre Antoine Sylvie Coutard Laurent Deschodt Philippe Gardère Marion Hernandez Claude Legentil Arnaud Lenoble Morgane Liard Norbert Mercier Olivier Moine Luca Sitzia Brigitte Van Vliet‐Lanoë 《Boreas: An International Journal of Quaternary Research》2014,43(3):699-711
Numerous periglacial features (polygons, nets, soil stripes, ice‐wedge pseudomorphs and sand‐wedge casts, involutions) have been recorded in France by examining bibliographical sources and aerial photographs. These data show that a large part of France was affected by permafrost during the Pleistocene and only the southern Aquitaine Basin and Languedoc seem to have been beyond its maximum extent. The first OSL ages obtained from the aeolian infill of wedge structures indicate that at least two phases of thermal contraction cracking occurred in southwestern France between ~25 and 36 ka. Chronostratigraphical data from loess in northern France indicate that these episodes correspond to the formation of ice‐wedge networks associated with tundra gleys. In the latter region, two additional permafrost episodes probably occurred during the Last Glacial, the older one corresponding to the end of Marine Isotope Stage (MIS) 4 around 60 ka and the more recent one to MIS 2 around 19–16 ka. Although stratigraphical data indicate that these episodes were relatively short (about one millennium), relict permafrost may have existed for longer periods in northern France. 相似文献
86.
Sylvie Vauclair 《Astrophysics and Space Science》2003,284(1):205-215
The element settling which occurs inside stars, also called `microscopic diffusion', due to the combined effect of gravity, thermal gradient, radiative acceleration and concentration gradient, leads to abundance variations which cannot be neglected in the computations of stellar structure. These processes where first introduced to account for abundance anomalies in `peculiar stars', but their importance in the so-called `normal' stars is now fully acknowledged, specially after the evidence of helium settling in the Sun from helioseismology. The reason why abundance variations as large as predicted by microscopic diffusion are not always observed is due to the influence of macroscopic motions, like rotation-induced mixing, or mass loss, which increase the settling time scales. In the present review, I discuss the theories of element settling and rotation-induced mixing and the importance of their coupling. I also give some comments about the links between diffusion processes and asteroseismology. 相似文献
87.
Darren O'Brien Paulo Garcia Jonathan Ferreira Sylvie Cabrit Luc Binette 《Astrophysics and Space Science》2003,287(1-4):129-134
Following the work of Garcia et al. (2001a) (GFCB), we compute the thermal properties and ionization structure of magnetically-driven disk winds. The original model's dominant heating function along the jet, ambipolar diffusion, is augmented by a mechanical heating term supposed to arise from weak shocks, as used by (Shang et al., 2002). We add this mechanical heating function to a cold disk wind model and calculate its effect on the jet as a whole. The temperature and ionization of the flow are calculated in the case of cold jet solutions consistent with the underlying accretion disk (Ferreira, 1997). These solutions are compared to those of (GFCB) in order to quantitatively determine the effect of the mechanical heating on the flow. We then use the computed thermal and ionization structures to calculate jet synthetic observations. We find that the addition of mechanical heating leads to higher electron fractions, in turn leading to increased line fluxes and line ratios approaching observed values. 相似文献
88.
Sylvie Jancart Anne Lemaitre Vincent Letocart 《Celestial Mechanics and Dynamical Astronomy》2003,86(4):363-383
Interested in the role of the inclination in our results (Jancart and Lemaitre, 2001), we analyze the process of resonance trapping due to general dissipation forces in the frame of the spatial restricted three body problem and in the case of external mean motion resonances. We compute our simulations by using the three-dimensional Extended Schubart Averaging integrator developed by Moons (1994) for all mean motion resonances. We complete it by adding the averaged contributions of general dissipative forces like Murray has proposed in the article (1994). The behavior of the inclination is especially pointed out. 相似文献
89.
Continental shelves are regions where heat flow is not measured directly by conventional marine techniques, but estimated from oil exploration data with possible bias. In order to overcome this problem, we recently proposed a method based on neural networks (Geophys J Int 2006, 166 :115) that provides better constraints on thermal conductivity: it allowed us to derive 161 heat flow estimates on the eastern margin of Canada, where previous studies had concluded to the existence of heat flow higher than that in the adjacent continent and ocean. We conversely found rather homogeneous values (∼45–55 mW m−2) all along and across the margins, from Labrador to Nova Scotia. The difference seems essentially related to the porosity of sediments that was not taken into account in previous studies. Our results support a high asymmetry for the conjugate Iberian‐Canadian margins, and could indicate that mantle heat flow increases abruptly from the Canadian shield to the margins. 相似文献
90.
New solar models are presented, which have been computed with the most recent physical inputs (nuclear reaction rates, equation
of state, opacities, microscopic diffusion). Rotation-induced mixing has been introduced in a way which includes the feed-back
effect of the μ-gradient induced by helium settling. A parametrization of the tachocline region below the convective zone
has also been added in the computations. The sound velocities have been computed in the models and compared to the seismic
Sun. Our best model is described in some detail. Besides the new physical inputs, the most important improvement concerns
the computations of μ-gradients during the solar evolution and their influence in slowing down rotation-induced mixing. This
process can explain why lithium is depleted in the present Sun while beryllium is not, and meanwhile why 3He has not increased at the solar surface for at least 3 Gyrs. 相似文献