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61.
Cybernetic Risk Analysis   总被引:2,自引:0,他引:2  
The Pearl Harbor case study reveals that risk analysis failure may be caused by any of a number of factors. However, the most important variables are system load, gain, lead time, and lag time. The dynamics of such cybernetic systems analysis constitute an important aspect in this regard. Four different risk management strategies, or organization designs, have been proposed in this paper. Each has a unique combination of the imputed variables and each has a unique cause of surprise, risk analysis failure, and crisis.  相似文献   
62.
Compliance Versus Risk in Assessing Occupational Exposures   总被引:1,自引:0,他引:1  
Assessments of occupational exposures to chemicals are generally based upon the practice of compliance testing in which the probability of compliance is related to the exceedance [γ, the likelihood that any measurement would exceed an occupational exposure limit (OEL)] and the number of measurements obtained. On the other hand, workers’ chronic health risks generally depend upon cumulative lifetime exposures which are not directly related to the probability of compliance. In this paper we define the probability of “overexposure” (θ) as the likelihood that individual risk (a function of cumulative exposure) exceeds the risk inherent in the OEL (a function of the OEL and duration of exposure). We regard θ as a relevant measure of individual risk for chemicals, such as carcinogens, which produce chronic effects after long-term exposures but not necessarily for acutely-toxic substances which can produce effects relatively quickly. We apply a random-effects model to data from 179 groups of workers, exposed to a variety of chemical agents, and obtain parameter estimates for the group mean exposure and the within- and between-worker components of variance. These estimates are then combined with OELs to generate estimates of γ and θ. We show that compliance testing can significantly underestimate the health risk when sample sizes are small. That is, there can be large probabilities of compliance with typical sample sizes, despite the fact that large proportions of the working population have individual risks greater than the risk inherent in the OEL. We demonstrate further that, because the relationship between θ and γ depends upon the within- and between-worker components of variance, it cannot be assumed a priori that exceedance is a conservative surrogate for overexposure. Thus, we conclude that assessment practices which focus upon either compliance or exceedance are problematic and recommend that employers evaluate exposures relative to the probabilities of overexposure.  相似文献   
63.
Perception of Ecological Risk to Water Environments   总被引:12,自引:1,他引:12  
This paper examines lay and expert perceptions of the ecological risks associated with a range of human activities that could adversely affect water resource environments. It employs the psychometric paradigm pioneered in characterizing perceptions of human health risks, which involves surveys to obtain judgments from subjects about risk items in terms of several important characteristics of the risks. The paper builds on a previous study that introduced ecological risk perception. This second study employs a larger, more diverse sample, a more focused topic area, and comparisons between lay and expert judgments. The results confirm that a small set of underlying factors explain a great deal of variability in lay judgments about ecological risks. These have been termed Ecological Impact, Human Benefits, Controllability , and Knowledge. The results are useful in explaining subjects' judgments of the general riskiness of, and need for regulation of, various risk items. The results also indicate several differences and areas of agreement among the lay and expert samples that point to potential key issues in future ecological risk management efforts for water resources.  相似文献   
64.
On the basis of discussion and analysis during and following an ATSDR science panel on the bioavailability of mercury in soils, it is apparent that the default assumption of 100% relative bioavailability for mercury-contaminated soils is excessively conservative. However, current knowledge does not allow the development of default assumptions or guidelines for determining relative bioavailability of mercury in soils. Until such default assumptions or guidelines can be developed, site-specific assays of bioavailability, preferably using either animal bioassays or validated in vitro techniques, may provide the best approach for estimating soil-mercury bioavailability.  相似文献   
65.
Chris Chapman  Mike Howden 《Omega》1997,25(6):707-714
This paper illustrates the value of several particular features of a first phase parametric approach to discounted cash flow (DCF) decision analysis when significant uncertainty is involved. It also illustrates the value of second phase probabilistic approaches to selected parameters for five quite different example reasons. The most controversial example reason concerns the discount rate. The particular example used to illustrate both phases may stimulate general interest because of the important issues involved, but it is argued that the two phase approach as a whole has a wide range of applications for decisions large and small.  相似文献   
66.
以中国知网数据库2007—2017年收录的题名中含有“员工创新行为”的293篇期刊论文作为数据来源,借助CiteSpace5.0软件绘制可视化知识图谱,对该时间段国内员工创新行为研究的年度发文量、发文机构、文献来源机构、代表性学者及研究热点进行可视化分析。研究结果表明:2007—2010年,员工创新行为研究的载文量较少但呈逐步增长趋势,2010—2017年,员工创新行为发文量增长趋势明显;发文量排名前20的研究机构中有19个为高校;载文量在5篇以上的期刊主要为经济管理类期刊;其研究热点主要集中在员工创新行为主体研究,以及个人特征、领导力、组织文化与氛围等员工创新行为前因变量研究。未来的研究方向为:开发适合中国情境的员工创新行为量表,在整体视角下探讨不同创新主体之间的关联及员工创新行为的结果变量等。  相似文献   
67.
社会网络对民间金融风险的影响已被广泛认可,但是,究竟什么样的网络结构有抑制风险的作用,什么样的网络结构有扩增风险的作用?以资金互助会为例,将互助会涉及的社会网络按结构特征分为单个会的会内网络和多个会的会间网络,研究可知:(1)越紧密的会内网络结构以及越大的网络规模越有利于民间金融风险的控制。(2)跨会网络具有抑制和扩增风险两种作用,它是协同监督和惩罚机制生效的基础,因而对风险具有控制作用,但这种作用只在中介成员为会首时才显著;同时,它也构成了风险传播的通道,导致资金被分散到多个会中,因而提升了系统性风险。  相似文献   
68.
    
选取14家上市商业银行2008—2016年的股票日度收益率数据,构建ARMA-GARCH-CoVaR模型,测度各家上市商业银行对整个银行体系的风险贡献程度以及商业银行之间的风险溢出强度。实证结果表明:每家商业银行都存在风险溢出效应,但不同商业银行对系统性风险的贡献程度存在明显差异,商业银行的系统性风险溢出程度与其自身风险水平的相关性较弱。值得注意的是,大型国有商业银行自身风险水平较低,但对银行系统性风险溢出强度最大;不同商业银行之间也存在风险溢出效应,但溢出程度呈现明显的非对称性,国有商业银行、城市商业银行对其关联银行的风险溢出大于股份制商业银行。此外,国内外经济金融形势对我国银行业系统性风险溢出具有重要影响,应将重大经济金融事件纳入到银行系统性风险的动态监测过程中。  相似文献   
69.
随着互联网的飞速发展,农产品质量安全事件借助网络媒体持续关联与聚合、发酵与扩散,极大地影响着公众的情感和态度,易引发集体非理性恐慌,网络时代信息扩散和迭代呈现全新特征和趋势,故加强农产品质量安全事件风险放大机制研究具有重要意义。基于斯梅尔塞的价值累加理论,结合“土坑酸菜”事件,利用Python技术获取媒体原始资料,对资料进行扎根编码分析,构建农产品质量安全事件风险放大机制模型。根据编码结果识别出农产品质量安全事件风险放大六大主范畴,包括结构性诱因、结构性紧张、一般化信念、(有效的)组织动员、社会控制、风险放大,将主范畴内容纳入价值累加理论六大因素中,分析表明农产品质量安全事件风险放大是以突发事件为分界点,分为前期蓄势、中期造势、紧急处理三个阶段,前期蓄势和中期造势阶段通过多轮循环相互反馈影响,最终放大农产品质量安全事件风险。在整个风险扩散过程中,网络是农产品质量安全事件风险的“社会放大站”,其加速了信息传播,强化了公众风险感知。本研究运用价值累加理论、基于宏观和微观整合层面,细化探究了网络时代农产品质量安全事件风险放大的完整过程机制,进一步完善了风险放大SARF研究框架,为相关研究做了有益补充。  相似文献   
70.
基于AHP的石油地质风险模糊综合评价体系研究   总被引:2,自引:0,他引:2  
石油地质勘探风险的综合评价是石油地质勘探中确定目标系统的重要环节.文章利用层次分析法与模糊综合评价法,构建了石油地质勘探风险综合评价体系,详细讨论了评价指标含义、评价标准及评价要点,并提出了适宜的评价方法.  相似文献   
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