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The paper presents the development of a cutting tool guide, specifically for the harvest of bamboo. The development was made based on precepts of eco-design and ergonomics, for prioritizing the physical health of the operator and the maintenance of the environment, as well as meet specific requirements of bamboo. The main goal is to spread the use of bamboo as construction material, handicrafts, among others, from a handy, easy assembly and material available tool. 相似文献
354.
Niklas Gudowsky Walter Peissl Mahshid Sotoudeh Ulrike Bechtold 《Poiesis & praxis》2012,9(1-2):101-123
Looking back on the many prophets who tried to predict the future as if it were predetermined, at first sight any forward-looking activity is reminiscent of making predictions with a crystal ball. In contrast to fortune tellers, today??s exercises do not predict, but try to show different paths that an open future could take. A key motivation to undertake forward-looking activities is broadening the information basis for decision-makers to help them actively shape the future in a desired way. Experts, laypeople, or stakeholders may have different sets of values and priorities with regard to pending decisions on any issue related to the future. Therefore, considering and incorporating their views can, in the best case scenario, lead to more robust decisions and strategies. However, transferring this plurality into a form that decision-makers can consider is a challenge in terms of both design and facilitation of participatory processes. In this paper, we will introduce and critically assess a new qualitative method for forward-looking activities, namely CIVISTI (Citizen Visions on Science, Technology and Innovation; www.civisti.org), which was developed during an EU project of the same name. Focussing strongly on participation, with clear roles for citizens and experts, the method combines expert, stakeholder and lay knowledge to elaborate recommendations for decision-making in issues related to today??s and tomorrow??s science, technology and innovation. Consisting of three steps, the process starts with citizens?? visions of a future 30?C40?years from now. Experts then translate these visions into practical recommendations which the same citizens then validate and prioritise to produce a final product. The following paper will highlight the added value as well as limits of the CIVISTI method and will illustrate potential for the improvement of future processes. 相似文献
355.
This article analyzes international commodity price movements, assesses food policies in response to price fluctuations, and explores the food security implications of price volatility on low-income groups. It focuses specifically on measurements, causes, and consequences of recent food price trends, variability around those trends, and price spikes. Combining these three components of price dynamics shows that the variation in real prices post-2000 was substantially greater than that in the 1980s and 1990s, and was approximately equal to the extreme volatility in commodity prices that was experienced in the 1970s. Macro policy, exchange rates, and petroleum prices were important determinants of price variability over 2005–2010, highlighting the new linkages between the agriculture-energy and agriculture-finance markets that affect the world food economy today. These linkages contributed in large part to misguided expectations and uncertainty that drove prices to their peak in 2008. The article also argues that there is a long-lasting effect of price spikes on food policy around the world, often resulting in self-sufficiency policies that create even more volatility in international markets. The efforts by governments to stabilize prices frequently contribute to even greater food insecurity among poor households, most of which are in rural areas and survive on the margin of net consumption and net production. Events of 2008—and more recently in 2010—underscore the impact of price variability for food security and the need for refocused policy approaches to prevent and mitigate price spikes. 相似文献
356.
J. Allen Williams Jr. Christopher Podeschi Nathan Palmer Philip Schwadel Deanna Meyler 《Sociological inquiry》2012,82(1):145-159
Picture books often play an important role in childhood socialization. Given the seriousness of environmental problems, we ask how natural, modified, and built environments have been portrayed in children’s books. To answer this question, we analyze the 296 books receiving Caldecott awards from 1938 to 2008. Two possibilities are explored with respect to content change. Growing concern about critical environmental problems, such as decline in biodiversity and deforestation, may have led to an increase in illustrations and stories about wild animals and the natural environment. Alternatively, the increasing isolation of people from the natural world may have resulted in a decline in the perceived relevance of these environmental issues and resulted in fewer stories and depictions. Our findings support the isolation hypothesis. There have been significant declines in depictions of natural environments and animals while built environments have become much more common. These findings suggest that today’s generation of children are not being socialized, at least through this source, toward an understanding and appreciation of the natural world and the place of humans within it. 相似文献
357.
Walter Forrest 《Journal of marriage and the family》2014,76(3):539-556
Although the empirical links between marriage and desistance are well established, very little is known about the degree to which cohabitation is associated with changes in criminal behavior. This is a significant oversight given that, among some segments of the population, cohabitation has become more common than marriage. In this article, the author investigated the links between cohabitation and desistance from crime. In doing so, particular attention was paid to the possibility that similarities between the apparent effects of marriage and cohabitation are obscured by variations in relationship quality and the increasing tendency for cohabitation to precede marriage. Analyses based on the National Longitudinal Survey of Youth 1997 (N = 3,232) indicate that cohabitation is associated with reductions in the rate of property and drug offending, but not the termination of violent, property, or drug offending. By contrast, marriage is consistently associated with large reductions in the rate of offending across the 3 crime categories as well as the abandonment of those crimes. These results provide greater insight into the links between adult family relationships, such as cohabitation and marriage, and desistance from crime. 相似文献
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Nancy Falxa-Raymond Matthew I. Palmer Timon McPhearson Kevin L. Griffin 《Urban Ecosystems》2014,17(3):807-824
Urban forests provide important environmental benefits, leading many municipal governments to initiate citywide tree plantings. However, nutrient cycling in urban ecosystems is difficult to predict, and nitrogen (N) use in urban trees may be quite different from use in rural forests. To gain insight into these biogeochemical and physiological processes, we compared foliar N characteristics of several common northeastern deciduous tree species across four newly planted New York City afforestation sites as well as at the Black Rock Forest (BRF), a rural oak-dominated forest in the Hudson Highlands, New York. Foliage sampled at BRF was consistently depleted in 15N compared to urban foliage, and Amelanchier canadensis, Nyssa sylvatica, Prunus serotina, and Quercus rubra showed significant variation in foliar nitrogen isotope signatures (δ15N) among the four urban sites. A. canadensis and P. serotina showed significantly greater ability to assimilate nitrate at BRF compared to urban sites, as measured through nitrate reductase activity (NRA). There were no significant differences in NRA among tree species growing at the four urban sites. Only P. serotina and N. sylvatica showed significant variation in foliar N concentrations (%N) both among urban sites and compared to BRF. The isotopic and %N data suggest greater N availability but less available nitrate at the newly planted urban sites compared to BRF, possibly due to different anthropogenic inputs or higher rates of nitrification and nitrate leaching at the recently planted urban sites compared to likely lower rates of N cycling in the intact rural forest. In addition, the tree species varied in their response to N availability at the urban sites, with potential implications for growth and survival. Understanding N cycling in urban systems and the associated physiological changes in vegetation is critical to a comprehensive evaluation of urban forest restoration, and may have implications for carbon sequestration and water quality issues associated with nitrate export, two important areas of management concern. 相似文献