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991.
Grotte XVI (Dordogne, France) contains a rich archaeological sequence that begins during the Mousterian and continues through the Magdalenian and includes Châtelperronian and early Aurignacian assemblages. Analyses of the ungulates from this site show no significant change in skeletal part representation, butchering intensity (as measured by cut mark numbers and placement), degree of bone fragmentation, and intensity of carnivore damage across the Middle-to-Upper Paleolithic transition. Relative taxonomic abundances of ungulates change significantly from the Mousterian to the early Aurignacian, but these changes are consistent with climatic forcing and continue throughout the sequence. Only the Magdalenian ungulate assemblage is clearly distinct from all others when examined in terms of these variables, perhaps because of altered predator/prey ratios on the local landscape. Cave bear relative abundances decline precipitously across the Middle-to-Upper Paleolithic transition; this decline may reflect increased human residence times and/or group sizes during this interval, just as Kurtén observed many years ago. 相似文献
992.
Land Ownership Risk and Urban Development 总被引:1,自引:0,他引:1
Under certainty, unlimited duration of private ownership of land provides landowners with efficient development incentives. However, in cases of ownership risk arising from title mistakes, fraud, boundary encroachment, or adverse possession, the statute of limitations sets a limit on how long agents have to establish or defend an ownership claim. This paper demonstrates that such restrictions speed the pace of land development and systematically affect the development density according to site location in the urban land market. It also offers an explanation of why land owners prefer a time limit on the ability to defend their ownership. It shows that the value–maximizing statute varies across sites in the spatial market. 相似文献
993.
Brian Crowe 《International affairs》2003,79(3):533-546
Taking as read the wide range of other instruments that the EU has for international influence (enlargement, aid, trade, association and other arrangements, etc.), the Common Foreign and Security Policy (CFSP), under pressure from the Kosovo conflict, has been shaped by two important decisions in 1999: the creation of the European Security and Defence Policy (ESDP) to give the EU a military capability when NATO as a whole is not engaged, and the appointment as the new High Representative for the CFSP of a high-profile international statesman rather than a senior civil servant.
A major European effort will still be needed if Europe is to be effective militarily, whether in the EU/ESDP or NATO framework. The management of the CFSP has been held back by the doctrine of the equality of all member states regardless of their actual contribution. This in turn leads to a disconnect between theory (policy run by committee in Brussels) and practice (policy run by the High Representative working with particular member states and other actors, notably the US). It has been difficult for Javier Solana to develop the authority to do this, not in competition with the Commission as so widely and mistakenly believed, as with member states themselves, and particularly successive rotating presidencies. It is important that misdiagnosis does not lead to politically correct solutions that end up with the cure worse than the disease. Ways need to be found to assure to the High Representative the authority to work with third countries and with the member states making the real contribution, while retaining the support of all. Then, with its own military capability, the EU can have a CFSP that is the highest common factor rather than the lowest common denominator, with member states ready to attach enough priority to the need for common policies to give Europeans a strong influence in the big foreign policy issues of the day. 相似文献
A major European effort will still be needed if Europe is to be effective militarily, whether in the EU/ESDP or NATO framework. The management of the CFSP has been held back by the doctrine of the equality of all member states regardless of their actual contribution. This in turn leads to a disconnect between theory (policy run by committee in Brussels) and practice (policy run by the High Representative working with particular member states and other actors, notably the US). It has been difficult for Javier Solana to develop the authority to do this, not in competition with the Commission as so widely and mistakenly believed, as with member states themselves, and particularly successive rotating presidencies. It is important that misdiagnosis does not lead to politically correct solutions that end up with the cure worse than the disease. Ways need to be found to assure to the High Representative the authority to work with third countries and with the member states making the real contribution, while retaining the support of all. Then, with its own military capability, the EU can have a CFSP that is the highest common factor rather than the lowest common denominator, with member states ready to attach enough priority to the need for common policies to give Europeans a strong influence in the big foreign policy issues of the day. 相似文献
994.
995.
Eva Siekierska Richard Labelle Louis Brunet Bill Mccurdy Peter Pulsifer Monika K. Rieger Linda O'Neil 《The Canadian geographer》2003,47(4):480-493
Thanks to advances in technology such as Internet-based mapping and the development of special inks, papers and global positioning systems, map making for vision impaired people can provide a range of products (e.g., tactile, haptic and audio-tactile maps) that can improve their independence, self-confidence and everyday life. The applications of tactile maps include learning spatial concepts and geography; audio-tactile maps combined with access to geospatial information can enhance mobility and independence. In 1998, the Mapping Services Branch (MSB) of the Earth Sciences Sector of Natural Resources Canada initiated a tactile mapping program. Now referred to as the Government on Line—Mapping for the Visually Impaired Project (Natural Resources Canada 2003a), it aims to serve the community with special needs, with emphasis on those who are blind or visually impaired, their teachers and mobility instructors. This technical paper discusses the various types of tactile and audio-tactile maps of Canada developed by the MSB in cooperation with its partners and describe the current research and development activities carried out within the project. It also leads the reader to further information on audio-tactile maps and touch- and sound-based computer interfaces. 相似文献
996.
The true cost of spatial data in Canada 总被引:2,自引:0,他引:2
Brian Klinkenberg 《The Canadian geographer》2003,47(1):37-49
The evolution of the Information Age, in Canada, has meant an unheralded parallel social evolution—the development of a class structure, if you will, that is tied to data accessibility. While other countries have made data freely available for use by industry, education and the public, Canada has opted to follow a restrictive data policy under which data are essentially available to a select few—those who can afford the prices. While anyone can purchase the data, not everyone can pay the price. The implications of this in our society are immense and are felt throughout our social structures. One obvious example of this is the lack of quality, high‐resolution Canadian data freely available for use in the Canadian education system, particularly in the university classes in which students today are usually introduced to GIS, visualization and data interpretation. Our students have data to work with, but often they are the freely available American data. They learn from examples derived in the mountains of Wyoming or the forests of Washington. How did this Canadian data restriction happen? In this paper, the evolution of GIS classicism is explored through examination of the evolution in Canada of GIS itself. The data situation elsewhere in the world is reviewed, the feasibility of ‘freeing’ data is discussed and a call for a radical change in the way data/information are handled in Canada is presented. 相似文献
997.
Four pottery kilns from Brühl-Pingsdorf (Germany) were dated by comparing their characteristic remanent magnetization with a curve of the palaeo-secular variation of the geomagnetic field. Archaeomagnetic results suggest last heating events between AD 775 and 1020. The archaeological evidence generally supports the relative temporal succession and the duration of use, but indicates that the kilns are about 150 years younger on average. Hence, a systematic offset between these independently developed chronologies must be considered. Rock magnetic parameters display radial variations through the kiln walls. These variations are controlled by the maximum temperature the rock was exposed to. These parameters were used to identify specimen which acquired a thermoremanent magnetization. 相似文献
998.
999.
J.A. Kieser A. Kelsen R. Love P.G.P. Herbison K.J. Dennison 《International Journal of Osteoarchaeology》2001,11(4):290-297
Dental wear and intrabony lesions were evaluated in a sample of 225 skulls (136 male) of pre‐contact New Zealand Maoris. The degree and direction of surface wear was scored according to the method of Molnar ( Molnar 1971 . Human tooth wear, tooth function and cultural variability. American Journal of Physical Anthropology34: 175–190) and revealed severe surface loss in both males and females with horizontal wear being the dominant pattern (62.4% male, 57.5% female). The width of coronal tissue above the pulp chamber, as well as the maximum depth and width of periapical lesions, was measured from both standard radiographs and digital images. The high prevalence of periapical pathology in the Maori underlined the extreme nature of dental wear in these people. It is postulated that this degree of tooth loss may be attributable to a change in diet from large birds to marine‐dependence, the introduction of the kumara to New Zealand, dental erosion and finally, to the excessive masticatory forces exerted by a robust facial complex on normally sized teeth. Fenestrated lesions were highly prevalent (83% of skulls) and were centered mostly on the maxilla, with an even distribution among tooth classes. The finding of periapical lesions in teeth with minimal observable wear was attributed to traumatic occlusion. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
1000.