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511.
512.
Trevelyan B Smallman-Raynor M Cliff AD 《Annals of the Association of American Geographers. Association of American Geographers》2005,95(2):269-293
This article seeks to advance an understanding of the spatial dynamics of one of the great emergent viral diseases of the twentieth century-poliomyelitis. From an apparently rare clinical condition occurring only sporadically or in small outbreaks before the late nineteenth century, poliomyelitis had, by the early 1950s, developed into a globally distributed epidemic disease. But, from 1955, continued growth was suddenly and dramatically reversed by the mass administration of inactivated (killed) and live (attenuated) poliovirus vaccines. After almost half a century of vaccine control, the world now stands on the brink of the global eradication of the disease. Against this background, the article draws upon information included in the U.S. Public Health Service's Public Health Reports and the U.S. Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report to examine the spatial dynamics of poliomyelitis during the phases of epidemic emergence (1910-1955) and vaccine-induced retreat (1955-1971) in the United States. It is shown that epidemic emergence was accompanied by shifts in the spatial center of activity from early diffusion poles in the northeastern states, to the western seaboard, and then finally to cover all the states of the Union. This was accompanied by accelerating epidemic propagation. The introduction of mass vaccination from the mid-1950s realigned spatial transmission of the disease, producing increased spatial volatility in the geographical center of activity and heightened dependence of epidemic outbreaks upon endemic reservoirs in the most populous states. Finally, the empirical results are generalized to suggest that the emergence and reemergence of many infectious diseases is a distinctively geographical process. 相似文献
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The American Civil War shipwrecks H. L. Hunley and USS Housatonic have been the focus of intensive archaeological investigations since the discovery of Hunley in 1995. H. L. Hunley , the world's first successful combat submarine, sank the Union blockader USS Housatonic in 1864, but sank immediately afterwards. In work done prior to the recovery of Hunley in 2000, site-formation processes for both vessels were a primary research focus—a necessary precursor to identifying battlefield behaviour. This paper presents research on the Hunley / Housatonic Naval Engagement Site, where both wrecks are treated as complementary components of a single battlefield site.
© 2006 The Authors 相似文献
© 2006 The Authors 相似文献
516.
Matthew Sothern 《对极》2004,36(2):183-190
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Margaret E. Beck Matthew E. Hill Jr. 《Journal of Archaeological Method and Theory》2004,11(3):297-333
Secondary refuse deposits such as middens may be used for intrasite comparisons of consumption, status, ethnicity, or activities. Our analysis of residence and household discard patterns in the modern village of Dalupa in the Pasil River Valley in Kalinga Province, the Philippines, suggests that midden assemblages may be used to compare the refuse of extended families. We define three types of middens (household, local, and communal) on the basis of catchment zones and describe their spatial distribution. Almost all middens in Dalupa are dominated by contributions from one family group based on mother–daughter relationships, despite some deviation from ideal residence patterns. 相似文献
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Xi Mei Kevin M. Curtin Daniel Turner Nigel M. Waters Matthew Rice 《Geographical analysis》2023,55(1):125-154
Accurately estimating the length of Vehicle Routing Problem (VRP) distances can inform transportation planning in a wide variety of delivery and service provision contexts. This study extends the work of previous research where multiple linear regression models were used to estimate the average distance of VRP solutions with various customer demands and capacity constraints. This research expands on that approach in two ways: first, the point patterns used in estimation have a wider range of customer clustering or dispersion values as measured by the Average Nearest Neighbor Index (ANNI) as opposed to just using a Poisson or random point process; second, the tour coefficient adjusted by this complementary spatial information is shown to exhibit statistically more accurate estimations. To generate a full range of ANNI values, point patterns were simulated using a Poisson process, a Matern clustering process, and a simple sequential inhibition process to obtain random, clustered, and dispersed point patterns, respectively. The coefficients of independent variables in the models were used to explain how the spatial distributions of customers influence the VRP distances. These results demonstrate that complementary spatial data can be used to improve operational results, a concept that could be applied more broadly. 相似文献
520.
Matthew Cole 《对极》2023,55(2):348-372
The so-called age of AI, industry 4.0, the fourth industrial revolution, etc. all attempt to conjure into existence a new technological paradigm. Should we believe the hype? This paper draws on neo-Schumpeterian and régulation theory to widen the scope of this debate and examine techno-economic and institutional discontinuities. In exploring these discontinuities, this paper argues, first, that growth regimes are not necessarily tenable as indicators of new paradigms, and, second, that there are (infra)structural discontinuities between the ICT/post-Fordist era and those of the AI/platform era. Platformisation entails a distinct institutional logic, regime of accumulation (RA) and mode of social régulation (MSR). The clusters of technological and institutional changes behind this shift have not yet been sufficiently addressed by economic geography and associated literatures. In reconceptualising the shift in terms of (infra)structural discontinuity, the paper synthesises neo-Schumpeterian and régulation theory to identify both technological and institutional changes in the régulation of capitalist accumulation. 相似文献