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Location and the nature of locally available employment opportunities is believed to shape labor force participation, job type, and wages. Analysts investigating this issue have encountered problems in operationalizing the concept of “locally available employment opportunities.” We first review the grounds for expecting a relationship between local context and employment outcomes for women and then critically assess the methods and measures that analysts have used to explore the relationship. Finally, we describe a new approach for measuring local employment context that consists of a fine-scaled measure individually tailored for each woman in the sample. Using discriminant analysis we ask whether the spatial variables measuring local employment context are important determinants of women's employment in female-dominated occupations. The results suggest that for most groups of women (defined by city or suburban residence and by sociodemographics) the spatial variables are not important. For well-educated, part-time employed women with young children, however, living in an area rich in female-dominated job opportunities increases the likelihood of having a job in a gender-typical occupation; for these women, the local employment context does affect labor market outcomes. 相似文献
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Laura C. McParland Margaret E. Collinson Andrew C. Scott Gill Campbell 《Archaeological and Anthropological Sciences》2009,1(4):249-261
Charcoal assemblages occur in both natural and archaeological settings. Cell wall reflectance values of charcoal in polished
blocks under oil provide a proxy for temperature of formation. This paper aims to (1) determine whether wildfire charcoals
and anthropological charcoals from various pyrotechnical activities can be distinguished using reflectance data and (2) establish
if re-charring (i.e. use of charcoal fuel) can be recognised in the archaeological record through analysis of laboratory-produced
re-charred charcoals and charcoals from an experimental iron smelt and traditional bronze casting which utilised charcoal
fuel. Reflectance frequency data from assemblages representing burning of charcoal, in this case of iron smelting and bronze
casting, indicates temperatures from above the mean value of charcoal production (>475°C) up to the maximum temperature reached
in the subsequent process (i.e. >475 to >1,100°C). In contrast, wildfire charcoals showed a range of values including material
with barely measurable reflectance (minimum values from 0.06% to 0.56%Ro) to maximum reflectance values varying from 1.65%Ro
(Tilford) to 3.8%Ro (Zacca). The mean wildfire reflectance indicated temperatures in the range 325–400°C, which can therefore
clearly be distinguished from that of the charcoal burning processes. The laboratory-produced re-charred charcoals take on
the reflectance value of the highest temperatures experienced; reflectance values were not constrained by the original temperature
of formation. High temperatures are most easily achievable by the burning of charcoal fuel, and hence high reflectance charcoals
are likely to represent re-charred charcoal. Therefore, this quantitative reflectance method can be used in archaeology to
determine the minimum temperature of formation of charcoals in anthropological processes which involve fire, can indicate
the likelihood of use of charcoal or wood as fuel and can distinguish between an assemblage of high temperature anthropogenic
charcoals and charcoals formed from natural wildfire. 相似文献
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User-Centred Time Geography for Location-Based Services 总被引:4,自引:0,他引:4
Martin Raubal Harvey J. Miller Scott Bridwell 《Geografiska annaler. Series B, Human geography》2004,86(4):245-265
Location‐based services assist people in their decision‐making during the performance of tasks in space. They do not consider the user's individual preferences, time constraints and possible subtasks to be performed. In order to account for these important aspects, a user‐centred spatio‐temporal theory of location‐based services is required. We propose such a theory by combining classical time geography with an extended theory of affordances. It assumes that affordances belong to three realms: physical, social‐institutional, and mental. In addition to covering the capability, coupling and authority constraints from time geography, this allows for a user‐centred perspective because affordances describe action possibilities with regard to a specific person. Furthermore, the integration of mental affordances offers the possibility to account for cognitive time constraints due to the duration of decision‐making processes. This new theory for location‐based services is closer to the individual user and more plausible with respect to their daily lives. A business traveller scenario is used as a case study to demonstrate this. 相似文献
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Questions relating to the ability of particular groups in society to access information and communications technologies (ICTs) have become a growing part of the academic and policy literature. The issues raised in this literature have revolved around a number of themes, many of which can be subsumed under concerns about a growing digital divide whereby society is being divided into information rich and information poor sectors. This differentiation can be between particular social groups irrespective of place, or between people in particular places be these large regional areas (e.g. metropolitan versus non‐metropolitan) or localities and communities within an urban area. This paper focuses on the existence of a ‘digital divide’ across the Sydney metropolitan area. Using ABS 2001 census data the paper presents an analysis of computer and internet access and use for clusters of local communities and focuses on how usage differs across communities as differentiated by socio‐economic status, household and family status and ethnic background. 相似文献