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841.
Dejian Lai Qiang Zhang Jose-Miguel Yamal Paula T. Einhorn Barry R. Davis 《统计学通讯:理论与方法》2017,46(18):8943-8951
Effective recruitment is a prerequisite for successful execution of a clinical trial. ALLHAT, a large hypertension treatment trial (N = 42,418), provided an opportunity to evaluate adaptive modeling of recruitment processes using conditional moving linear regression. Our statistical modeling of recruitment, comparing Brownian and fractional Brownian motion, indicates that fractional Brownian motion combined with moving linear regression is better than classic Brownian motion in terms of higher conditional probability of achieving a global recruitment goal in 4-week ahead projections. Further research is needed to evaluate how recruitment modeling can assist clinical trialists in planning and executing clinical trials. 相似文献
842.
The objective of this paper is to study the Phase I monitoring and change point estimation of autocorrelated Poisson profiles where the response values within each profile are autocorrelated. Two charts, the SLRT and the Hotelling's T2, are proposed along with an algorithm for parameter estimation. The detecting power of the proposed charts is compared using simulations in terms of the signal probability criterion. The performance of the SLRT method in estimating the change point in the regression parameters is also evaluated. Moreover, a real data example is presented to illustrate the application of the methods. 相似文献
843.
William Skinner 《The Asia Pacific Journal of Anthropology》2018,19(3):245-263
Grape phylloxera is an insect pest that has destroyed vineyards and brought ruin to winegrowing regions worldwide. In South Australia, however, strong biosecurity regulations have ensured it has remained absent. In this absence phylloxera takes on powerful symbolic value, and regional viticultural identities may be imagined in relation to the presence of phylloxera elsewhere. This paper draws from ethnographic research with grape growers and wine producers in McLaren Vale, a region whose vineyards are understood through this ‘phylloxera-free’ paradigm. The article specifically explores controversies around modification of South Australian biosecurity regulations in a way that favoured large winegrowing corporations’ need to more easily move material between regions, to the perceived detriment of vineyard security. The phylloxera risk has economic, social and symbolic dimensions in McLaren Vale, where the insect has become symbolically aligned with the most impersonal, pervasive and destructive aspects of globalised wine capitalism. 相似文献
844.
William Pawlett 《Journal for Cultural Research》2018,22(1):1-15
This paper re-examines the long-established notion of ‘media events’ by contrasting and critically appraising three distinct approaches to the question of media events. These are: ritual theory associated with Daniel Dayan and Elihu Katz, secondly, Jean Baudrillard’s approach rooted in his notions of simulation and ‘non-events’ and, finally, the more recent performative approaches to media and mediation. I take Sarah Kember and Joanna Zylinska’s reading of media events presented in Life After New Media (2012) as exemplary of the performative approach. An argument is made that the accounts of media events offered by performative approaches add very little, and, indeed, lack the critical insightfulness of the earlier approaches. Both ritual theory and Baudrillard’s thought are briefly reappraised and, against Nick Couldry, I try to show that these accounts are not characterised by binary and reductive thinking. The major misunderstandings concern the nature of the sacred and profane dualism and the further dualisms developed in Baudrillard’s thought, particularly the figures of implosion and reversibility. Finally, Baudrillard’s position on technology is addressed and the paper concludes with the suggestion that his account is not solely negative, since technological developments are not only at the mercy of ironic reversals they may also enable new rituals of disappearance. 相似文献
845.
846.
We consider the intersection between two striking U.S. trends: dramatic increases in the imprisonment of fathers and increases in the proportion of mothers who have children with more than one partner (multiple-partner fertility, or MPF). Using matched longitudinal administrative data that provide unusually comprehensive and accurate information about the occurrence and timing of imprisonment, fertility, and MPF for the population of the state of Wisconsin, we consider the relationship between paternal imprisonment and MPF among unwed mothers. Employing discrete-time event history analysis with multinomial logistic regression, we model the occurrence and timing of the mother’s second birth, distinguishing between a birth with the same father and a birth with a different father, and distinguishing between current imprisonment and a history of imprisonment. We find that current imprisonment is associated with an increased likelihood of MPF and a decreased likelihood of fertility with the same father (compared with no additional birth) and that a history of imprisonment is associated with increased MPF in some models but not in our preferred model. To control for unobserved heterogeneity among mothers and assess the evidence of a causal effect of fathers’ imprisonment, we also employ the case-time-control method, a fixed-effects method for the analysis of nonrepeated events. Results suggest that fathers’ current imprisonment may increase mothers’ MPF. Policy implications are discussed. 相似文献
847.
The Role of Behavioral Responses in the Total Economic Consequences of Terrorist Attacks on U.S. Air Travel Targets
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Adam Rose Misak Avetisyan Heather Rosoff William J. Burns Paul Slovic Oswin Chan 《Risk analysis》2017,37(7):1403-1418
U.S. airports and airliners are prime terrorist targets. Not only do the facilities and equipment represent high‐value assets, but the fear and dread that is spread by such attacks can have tremendous effects on the U.S. economy. This article presents the methodology, data, and estimates of the macroeconomic impacts stemming from behavioral responses to a simulated terrorist attack on a U.S. airport and on a domestic airliner. The analysis is based on risk‐perception surveys of these two scenarios. The responses relate to reduced demand for airline travel, shifts to other modes, spending on nontravel items, and savings of potential travel expenditures by U.S. resident passengers considering flying domestic routes. We translate these responses to individual spending categories and feed these direct impact results into a computable general equilibrium (CGE) model of the U.S. economy to ascertain the indirect and total impacts on both the airline industry and the economy as a whole. Overall, the estimated impacts on GDP of both types of attacks exceed $10B. We find that the behavioral economic impacts are almost an order of magnitude higher than the ordinary business interruption impacts for the airliner attack and nearly two orders of magnitude higher for the airport attack. The results are robust to sensitivity tests on the travel behavior of U.S. residents in response to terrorism. 相似文献
848.
Disasters garner attention when they occur, and organizations commonly extract valuable lessons from visible failures, adopting new behaviors in response. For example, the United States saw numerous security policy changes following the September 11 terrorist attacks and emergency management and shelter policy changes following Hurricane Katrina. But what about those events that occur that fall short of disaster? Research that examines prior hazard experience shows that this experience can be a mixed blessing. Prior experience can stimulate protective measures, but sometimes prior experience can deceive people into feeling an unwarranted sense of safety. This research focuses on how people interpret near‐miss experiences. We demonstrate that when near‐misses are interpreted as disasters that did not occur and thus provide the perception that the system is resilient to the hazard, people illegitimately underestimate the danger of subsequent hazardous situations and make riskier decisions. On the other hand, if near‐misses can be recognized and interpreted as disasters that almost happened and thus provide the perception that the system is vulnerable to the hazard, this will counter the basic “near‐miss” effect and encourage mitigation. In this article, we use these distinctions between resilient and vulnerable near‐misses to examine how people come to define an event as either a resilient or vulnerable near‐miss, as well as how this interpretation influences their perceptions of risk and their future preparedness behavior. Our contribution is in highlighting the critical role that people's interpretation of the prior experience has on their subsequent behavior and in measuring what shapes this interpretation. 相似文献
849.
850.
Urban and agricultural soils: conflicts and trade-offs in the optimization of ecosystem services 总被引:2,自引:0,他引:2
H. Setälä R. D. Bardgett K. Birkhofer M. Brady L. Byrne P. C. de Ruiter F. T. de Vries C. Gardi K. Hedlund L. Hemerik S. Hotes M. Liiri S. R. Mortimer M. Pavao-Zuckerman R. Pouyat M. Tsiafouli W. H. van der Putten 《Urban Ecosystems》2014,17(1):239-253
On-going human population growth and changing patterns of resource consumption are increasing global demand for ecosystem services, many of which are provided by soils. Some of these ecosystem services are linearly related to the surface area of pervious soil, whereas others show non-linear relationships, making ecosystem service optimization a complex task. As limited land availability creates conflicting demands among various types of land use, a central challenge is how to weigh these conflicting interests and how to achieve the best solutions possible from a perspective of sustainable societal development. These conflicting interests become most apparent in soils that are the most heavily used by humans for specific purposes: urban soils used for green spaces, housing, and other infrastructure and agricultural soils for producing food, fibres and biofuels. We argue that, despite their seemingly divergent uses of land, agricultural and urban soils share common features with regards to interactions between ecosystem services, and that the trade-offs associated with decision-making, while scale- and context-dependent, can be surprisingly similar between the two systems. We propose that the trade-offs within land use types and their soil-related ecosystems services are often disproportional, and quantifying these will enable ecologists and soil scientists to help policy makers optimizing management decisions when confronted with demands for multiple services under limited land availability. 相似文献