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81.
Henri Menu Suzanne Hand Bernard Sigé 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):319-331
An upper molar of a small bat, here described from an early Miocene freshwater lime-stone deposit at Riversleigh, northwestern Queensland, is the oldest record in Australia of the microchiropteran family Vespertilionidae. The new taxon is referred to the cosmopolitan genus Leuconoe, but it does not appear to be closely related to the two extant Australian species of this genus. 相似文献
82.
K. Su J.‐P. Latham D. Pavlidis J. Xiang F. Fang P. Mostaghimi J. R. Percival C. C. Pain M. D. Jackson 《Geofluids》2015,15(4):592-607
Accurate simulation of multiphase flow in fractured porous media remains a challenge. An important problem is the representation of the discontinuous or near discontinuous behaviour of saturation in real geological formations. In the classical continuum approach, a refined mesh is required at the interface between fracture and porous media to capture the steep gradients in saturation and saturation‐dependent transport properties. This dramatically increases the computational load when large numbers of fractures are present in the numerical model. A discontinuous finite element method is reported here to model flow in fractured porous media. The governing multiphase porous media flow equations are solved in the adaptive mesh computational fluid dynamics code IC‐FERST on unstructured meshes. The method is based on a mixed control volume – discontinuous finite element formulation. This is combined with the PN+1DG‐PNDG element pair, which has discontinuous (order N+1) representation for velocity and discontinuous (order N) representation for pressure. A number of test cases are used to evaluate the method's ability to model fracture flow. The first is used to verify the performance of the element pair on structured and unstructured meshes of different resolution. Multiphase flow is then modelled in a range of idealised and simple fracture patterns. Solutions with sharp saturation fronts and computational economy in terms of mesh size are illustrated. 相似文献
83.
PéTer Losonczi 《Political Theology》2015,16(2):116-129
AbstractThis paper aims at analyzing what the author calls the “hidden nexus between” Metz and Schmitt. Relying on a Schmittean reference to Metz, pointing to certain conceptual and theoretical, as well as historical components, the paper argues that it is a shared concern about the mistaken modern — utopian reworking of eschatology. The paper also demonstrates how the more recent Metzean rethinking of the problem of theodicy works further this eschatological theme. 相似文献
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At Nunalleq, a pre-contact Yup'ik Eskimo village site in Alaska (14th–17th century AD), abundant insect remains from highly organic substrates preserved within permafrost offer a unique opportunity to investigate past ecological and living conditions. This paper presents the preliminary results obtained from the analysis of two samples collected from floor layers in sod houses. The numerous and diverse insect remains highlight the exciting potential of archaeoentomology for reconstructing past ecological conditions, resource exploitation and the use of space at northern hunter–gatherer sites and have permitted the development of a strategy for the future collection of archaeoentomological data at permafrost-preserved sites in Alaska and elsewhere. 相似文献
86.
Andreas Angourakis José Ignacio Santos José Manuel Galán Andrea L. Balbo 《Environmental Archaeology》2015,20(4):349-363
AbstractA consistent access to food is paramount for humans at individual and group level. Besides providing the basic nutritional needs, access to food defines social structures and has stimulated innovation in food procurement, processing and storage. We focus on the social aspects of food storage, namely the role of cooperation for the emergence and maintenance of common stocks. Cooperative food stocks are examined here as a type of common-pool resource, where appropriators must cooperate to avoid shortage (i.e. the tragedy of commons). ‘Food for all’ is an agent-based model in which agents face the social dilemma of whether or not to store in a cooperative stock, adapting their strategies through a simple reinforcement learning mechanism. The model provides insights on the evolution of cooperation in terms of storage efficiency and considering the presence of social norms that regulate reciprocity. For cooperative food storage to emerge and be maintained, a significant dependency on the stored food and some degree of external pressure are needed. In fact, cooperative food storage emerges as the best performing strategy when facing environmental stress. Likewise, an intermediate control over reciprocity favours cooperation for food storage, suggesting that concepts of closed reciprocity are precursors to cooperative stocks, while excess control over reciprocity is detrimental for such institution. 相似文献
87.
Biodiversity and Environmental Change: Monitoring,Challenges and Direction edited by D. LINDENMAYER,E. BURNS,N. THURGATE and A. LOWE (eds), CSIRO Publishing,Melbourne, Australia, 2014, xiv + 624 pp,ISBN: 9780643108561 (hardback), AU$120.00
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CATE MACINNIS‐NG 《Geographical Research》2015,53(2):226-227
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