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991.
The main impetus to the development of information about major industrial hazards in the European Community comes from the so-called Seveso Directive, which defines an information network and requires the generation and transmission of information as the basis for accident prevention and risk management. This important policy development, which calls for the formal identification and analysis of major hazards and the communication of risk information to members of the public, presents new opportunities and challenges to risk analysis and research in Europe. This paper briefly reviews the accidents that gave rise to the Directive and shaped its content, and then summarizes its requirements. The status of its implementation in the EC Member States is discussed, with special emphasis given to the comparison of safety analysis practices, the Major Accident Reporting System (MARS), and risk communication. Some new research directions stimulated by the Directive are identified.  相似文献   
992.
This paper considers decision problems where: (1) The exact probability distribution over the states of nature is not precisely known, but certain prior information is available about the possibilities of these outcomes; (2) A prior distribution over the states of nature is known, but new constraint information about the probabilities becomes available. The maximum entropy principle asserts that the probability distribution with maximum entropy, satisfying the prior knowledge, should be used in the decision problem. The minimum cross-entropy principle says that the posterior distribution is the one which minimizes cross-entropy, subject to the new constraint information. The entropy principles have not gone uncriticized, and this literature, together with that justifying the principles, is surveyed. Both principles are illustrated in a number of situations where the distribution is either discrete or continuous. The discrete distribution case with prior interval estimates based on expert opinions is considered in detail.  相似文献   
993.
We present a hypothetical case study using the Years of Potential Life Lost (YPLL) metric to compare cancer risks incurred by residents living near a Superfund site to occupational fatality risks incurred by workers employed in that site's remediation. Since cancer occurs late in life, and because we assume its mortality rate is 60%, each case results in 8.8 YPLL. Each occupational fatality, which typically occurs earlier in life, results in 38.1 YPLL. In our case study, the residential population of 5000 incurred 1.3 YPLL, compared to 5.7 YPLL incurred by the 500 workers. Several uncertain assumptions may influence our calculations; moreover, occupational risks may be viewed as more "voluntary" than risks incurred by residents. However, because the magnitude of the YPLL incurred by workers and residents may be comparable, risk managers should consider occupational risks when evaluating remedial alternatives.  相似文献   
994.
A questionnaire measuring cognitive and affective representations of terror risk was developed and tested in Turkey and Israel. Participants in the study were university students from the two countries (n= 351). Four equivalent factors explained terror risk cognitions in each sample: costs, vulnerability, trust, and control. A single negative emotionality factor explained the affective component of terror risk representations in both samples. All factors except control could be measured reliably. Results supported the validity of the questionnaire by showing expected associations between cognitions and emotions, as well as indicating gender differences and cultural variations. Current findings are discussed in relation to previous results, theoretical approaches, and practical implications.  相似文献   
995.
As a result of the Chernobyl nuclear power plant accident in 1986, large forested areas in Europe were contaminated by radionuclides. Extensive societal pressure has been exerted to decrease the radiation dose to the population and to the environment. Thus, in making abatement and remediation policy decisions not only economic costs, but also human and environmental risk assessment are desired. Forest remediation by organic layer removal, one of the most promising cleanup policies, is considered in this paper. Ecological risk assessment requires evaluation of the radionuclide distribution in forests. The FORESTPATH model(1,2) is used for predicting the radionuclide fate in forest compartments after deposition as well as for evaluating the application of the remedial policy. Time of intervention and radionuclide deposition profile was predicted as being crucial for the remediation efficiency. Risk assessment conducted for a critical group of forest users in Belarus shows that consumption of forest products (berries and mushrooms) leads to about 0.004% risk of a fatal cancer. Cost-benefit analysis for forest cleanup suggests that complete removal of organic layer is too expensive for application in Belarus.  相似文献   
996.
The current French bovine spongiform encephalopathy (BSE) surveillance system, based on rapid testing of all cattle over 24 months of age and on clinical diagnosis, detects all clinical cases and some preclinical cases of BSE. Several indicators point to a marked shrinkage of the French BSE epidemic in recent years, owing to risk reduction measures. Meat and bone meal, the only known vector of the BSE agent, was banned in feed for all farmed species in November 2000. Thus the surveillance system may be relaxed. The objective of this risk assessment study was to provide information for decisionmakers on the minimum age at which healthy and high-risk cattle now need to be screened with rapid tests. For this purpose, we used the back-calculation method to project the course of the BSE epidemic. We examined the predicted patterns of the number and age distribution of cases of BSE that would be detected by the different existing surveillance streams. Various theoretical sensitivities of rapid tests were explored. Assuming that feed-borne sources of infection no longer exist, and that BSE does not occur spontaneously, our models suggest that it would have been possible to raise the minimum age for rapid tests to 66 months in early 2006, whereas theoretical reasoning, based on the assumption that the total meat and bone meal ban was effective in November 2001, suggests that this age cutoff could only be raised to 48 months in early 2006. These results only apply to cattle born and bred in France. If the situation remains unchanged, the age cutoff could be raised incrementally each year.  相似文献   
997.
We review recent research on time-varying risk premiums, including attempts to explain rejections by baillie and others of the unbiasedness hypothesis. Using spot and forward foreign exchange rates we discuss the evidence for time-varying risk premiums, relate it to general equilibrium theories of asset pricing, and describe the artificial economy methodology.  相似文献   
998.
This study aimed to identify homeless youths’ lifestyle and trauma-related risk factors as well as protective factors associated with alcohol use disorder or no disorder and drug use disorder or no disorder. Youth receiving homeless services in Denver (n = 201), Austin (n = 200), and Los Angeles (n = 200; N = 601) completed quantitative interviews assessing demographic information, alcohol and drug use, homeless lifestyle risk factors, trauma-related risk factors, and protective factors. Findings showed differences in trauma-related risk factors between alcohol and drug use disorders, but not homeless lifestyle risks. Protective factors predicted substance use disorders beyond risk factors. Understanding trauma-related risk and protective factors associated with substance use disorders could improve interventions.  相似文献   
999.
Crime risk perception is known to be an important determinant of individual well-being. It is therefore crucial that we understand the factors affecting this perception so that governments can identify the (public) policies that might reduce it. Among such policies, public resources devoted to policing emerge as a key instrument not only for tackling criminal activity but also for impacting on citizens’ crime risk perception. In this framework, the aim of this study is to analyze both the individual and neighbourhood determinants of citizens’ crime risk perception in the City of Barcelona (Spain) focusing on the effect of police proximity and taking into account the spatial aspects of neighbourhood characteristics. After controlling for the possible problems of the endogeneity of police forces and crime risk perception and the potential sorting of individuals across neighbourhoods, the results indicate that crime risk perception is reduced when non-victims exogenously interact with police forces. Moreover, neighbourhood variables, such as proxies of social capital and the level of incivilities, together with individual characteristics have an impact on citizens’ crime risk perception.  相似文献   
1000.
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