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51.
This article describes the development of a GIS-based model of historical drought and population change in western Canada, designed to support qualitative field research into drought adaptation and migration. The model combines digitized census data and recently available modeled historical climate data at a 10 km2 grid cell scale and can be used to generate maps of ‘hotspots’ where historical declines in rural populations may be associated with extended periods of heat and lack of precipitation. The results suggest a promising avenue for expanding and refining GIS-based modeling of historical human–climate interactions to support qualitative research and to potentially serve as a stepping stone toward forecasting future risk areas of drought-related migration in continental dryland areas.  相似文献   
52.
Hydro-political dependencies between countries are widely regarded as having important implications for international water cooperation and conflict. Quantitative ex-post empirical research on the subject so far uses very simple characterizations of international river geography to proxy for such dependencies, though. The authors developed a new geo-spatial dataset for water catchments worldwide. This dataset combines elevation models, flow accumulation approaches, hydrological data, and data on international boundaries to generate more precise and nuanced measures of hydro-political dependencies among riparian countries. The paper discusses these measurement concepts, illustrates how dependencies are distributed worldwide, and revisits three prominent quantitative studies on the issue to show how using improved data affects empirical findings. In contrast to a very popular presumption, upstream–downstream dependencies turn out to have a very small to insignificant effect on international water cooperation or conflict.  相似文献   
53.
In this paper we use non-ambiguous collections and sightings data from the 18th century to generate potential distribution models of three species of South American ungulates. These ungulates (Lama guanicoe -guanaco-; Ozotoceras bezoarticus -pampas deer- and Blastoceros dichotomus -marsh deer-) have different and specific environmental requirements. Through MaxEnt software, twenty-two environmental variables that characterize the distribution area of each species are defined. Once the models are generated, they are compared with the faunal associations found at Late Holocene archaelogical sites in order to infer paleoenvironmental conditions. We also discuss the role played by humans in the faunal associations which are "anomalous" or inconsistent with those models, like the spatial overlap of guanaco and marsh deer.  相似文献   
54.
What is the dynamic value of the creative industries from the economic perspective? This paper seeks to answer this question by proposing four models of the relationship between the creative industries and the whole economy, then examining the evidence for each. We find that growth models fit the data well, but not everywhere. We discuss the methodological and empirical basis for this finding and its implications for economic and cultural policy.  相似文献   
55.
The debate over whether turn-of-the-century immigrants were influenced more by their cultural heritage or by their socioeconomic circumstances when deciding to send their children either to school or to work, serves to illustrate the interplay between theory and evidence in the research process. The authors examine how ethnicity, the local economy, and the family economy affected children's participation in school and work. Using cost-of-living data from 1888-1890, they find that the effects of ethnicity on children's school participation were attenuated by local and family economy factors, and in some cases ethnic group coefficients no longer differed significantly from those of Yankees. The significant effects of ethnicity on children's work participation, however, persisted even when local and family economy factors were taken into consideration.  相似文献   
56.
Abstract

The authors reconstruct processes of ethnic identification among residents of rural northeast China from the end of the eighteenth century to the beginning of the twentieth through an analysis of naming behavior. They apply discrete-time event-history techniques to individual life histories compiled from longitudinal, nominative household-register data from state farms in what is now Liaoning Province to identify the individual and household circumstances associated with the adaptation of Han or Manchu names, focusing on the role of heredity and status. Ethnic identification in late imperial northeast China was potentially fluid. Many residents were descended from migrants from Shandong who became hereditary tenants on state land administered by a system of Manchu government known as the Eight Banners. As banner people, or qiren, these residents could legitimately claim to be Manchu. As descendants of Shandong migrants, they could also claim to be Han. They could express their choice of ethnic identity through their choice of names not just for their children but also for themselves. Names not only express ethnic self-identification, but their registration by state authorities in the analyzed data also implies official recognition and legitimacy. The authors' results demonstrate that ethnic identity was not hereditary but subject to individual and family choice.  相似文献   
57.
The Great Dismal Swamp in North Carolina and Virginia has a history of profound significance to scholars and historians of North American diasporas. Between 1630 and 1865, thousands of maroons, enslaved canal company laborers, and disenfranchised Native Americans lived within this morass and formed communities that were connected through a dynamic swamp-wide political economy. The Great Dismal Swamp Landscape Study has been initiated to explore the archaeological landscapes of these Diasporans. This essay discusses several aspects of the theoretico-analytical research model that has guided this ongoing project. Also, included are brief explications on the methods and results of the first season of archaeological survey in the Great Dismal Swamp National Wildlife Refuge.  相似文献   
58.
The last few decades have witnessed a rapid rise in the use of foraging models derived from behavioral ecology to explain and predict temporal and spatial differences in faunal assemblages. Although these models build on conventional ideas about utility firmly embedded in zooarchaeological analyses, when cast in an evolutionary framework these ideas produce some of the most sophisticated and elegant interpretations of archaeofaunas to date. In this article I review the methodological and practical strengths and weaknesses of current zooarchaeological applications of foraging models. Recent applications of foraging models to the zooarchaeological record reveal important variability in human-prey interactions across time and space. Case-specific applications generate theoretical and methodological advances that augment and are complementary to model building in allied fields. Recent applications also identify shortcomings in the underlying assumptions and rationale of some foraging models that mirror past and on-going discussions in anthropology and biology. I discuss how these shortcomings can fruitfully direct future applications and research in foraging economics.  相似文献   
59.
Archaeological samples of human and faunal remains dating from the Viking (9–11th century AD) and Early Christian (11–12th century AD) periods of Gotland, Sweden were assayed through stable carbon and nitrogen isotope analysis in order to investigate whether changes in subsistence occurred between these periods, particularly regarding the importance of seafood. The study was concerned with how the dietary regime of the Baltic trading port and farming settlement at Ridanäs, Gotland was affected by the widespread environmental and sociocultural transformations that characterized the end of the Viking Age. More generally, the research considers how changes in both food procurement and preference may account for observed differences in the dietary regimes of individuals from the Viking Age and the Early Christian period.  相似文献   
60.
Tree‐ring dating involves matching sequences of ring widths from undated timbers to dated sequences known as ‘master’ chronologies. Conventionally, the undated timbers (from a building or woodland) are sequentially matched against one another, using t‐tests to identify the relative offsets with the ‘best’ match, thus producing a ’site’ chronology. A date estimate is obtained when this is matched to a local master chronology of known calendar age. Many tree‐ring sequences in the UK produce rather low t‐values and are thus declared not to have a ‘best’ match to a master chronology. Motivated by this and the routine use of Bayesian statistical methods to provide a probabilistic approach to radiocarbon dating, this paper investigates the practicality of Bayesian dendrochronology. We explore a previously published model for the relationship between ring widths and the underlying climatic signal, implementing it within the Bayesian framework via a simulation‐based approach. Probabilities for a match at each offset are produced, removing the need to identify a single ‘best’ match. The Bayesian model proves successful at matching in both simulated and real examples.  相似文献   
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