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71.
贵州省主导产业选择的投入产出分析   总被引:1,自引:0,他引:1  
正确地选择主导产业对一个地区的经济发展有着至关重要的作用。本文以贵州省投入产出表为依据,运用投入产出分析方法,对地区主导产业的选择进行探讨,为贵州省产业结构调整和区域经济发展规划提供经济学意义的理论参考。  相似文献   
72.
研究了一类具有v+1个亏值的v-值整代数体函数,利用整代数体函数的级与特征函数及其亏值亏量的定义和性质,借助线性无关性、克兰姆法则、Jensen公式及对数导数定理进行分析推理,得出这类整代数体函数的所有亏量之和不超过v.  相似文献   
73.
通过对环境生态成本的分析,根据上海市2002年的投入产出表,建立了基于资源一经济一环境绿色投入产出表的绿色GDP核算方法。利用这一方法对2010年上海世博会对上海经济一环境影响进行分析研究,结果反映了上海世博会对上海的综合影响。  相似文献   
74.
To ascertain the viability of a project, undertake resource allocation, take part in bidding processes, and other related decisions, modern project management requires forecasting techniques for cost, duration, and performance of a project, not only under normal circumstances, but also under external events that might abruptly change the status quo. We provide a Bayesian framework that provides a global forecast of a project's performance. We aim at predicting the probabilities and impacts of a set of potential scenarios caused by combinations of disruptive events, and using this information to deal with project management issues. To introduce the methodology, we focus on a project's cost, but the ideas equally apply to project duration or performance forecasting. We illustrate our approach with an example based on a real case study involving estimation of the uncertainty in project cost while bidding for a contract.  相似文献   
75.
Consider a website and the surfers visiting its pages. A typical issue of interest, for example while monitoring an advertising campaign, concerns whether a specific page has been designed successfully, i.e. is able to attract surfers or address them to other pages within the site. We assume that the surfing behaviour is fully described by the transition probabilities from one page to another, so that a clickstream (sequence of consecutively visited pages) can be viewed as a finite-state-space Markov chain. We then implement a variety of hierarchical prior distributions on the multivariate logits of the transition probabilities and define, for each page, a content effect and a link effect. The former measures the attractiveness of the page due to its contents, while the latter signals its ability to suggest further interesting links within the site. Moreover, we define an additional effect, representing overall page success, which incorporates both effects previously described. Using WinBUGS, we provide estimates and credible intervals for each of the above effects and rank pages accordingly.  相似文献   
76.
当前,影响和制约中国电子商务进一步发展的主要问题集中表现在“信用缺失”问题上,它导致人们对网上交易仍心存疑虑,物流配送滞后,商品流通不畅,企业计算机应用水平不高,高水平网络人才匮乏,与电子商务相关的法规体制不够健全。为此,中国电子商务必须建立诚信长效机制,加快物流配送体系建设,构筑有效的社会物流配送系统.加快推广电子商务知识,强化电子商务人才培养,健全与国际接轨的电子商务法律体系。  相似文献   
77.
白先勇尝试运用现代派文学的表现技巧——意识流创作手法始于与台湾大学外文系同学创办《现代文学》杂志。以后,随着作家自身经历的变化和对意识流创作理论认识的深入,其笔下意识流这一创作手法呈现出鲜明的“模仿试睑一成熟定型——在扬弃中提升”的变化轨迹。  相似文献   
78.
在分析便利商业特征和北京便利商业现状及问题的基础上,提出将便利商业体系划分为三个维度:功能维、业态维、区址维,对三个维度的内涵进行了分析。  相似文献   
79.
大学英语语调交际功能的课堂教学研究与实践   总被引:1,自引:1,他引:0  
大学英语课堂教学不能只注意学生英语语音,更重要的是在语音的基础上掌握语调及其功能。从学生语言运用能力的角度来说语调的教学比纯语音教学应该更重要,因为同一个单词或句子用不同的语调在同等交际背景下传递出的含义就会不同,有时还会是相反的含义。以语调的交际功能为出发点,运用语用学的相关理论,设计并分析了基于语调交际功能的英语课堂教学模式的实践,探讨了这种模式的可行性和有效性,以引起大家对语调教学的重新思考。  相似文献   
80.
This article presents a framework for using probabilistic terrorism risk modeling in regulatory analysis. We demonstrate the framework with an example application involving a regulation under consideration, the Western Hemisphere Travel Initiative for the Land Environment, (WHTI‐L). First, we estimate annualized loss from terrorist attacks with the Risk Management Solutions (RMS) Probabilistic Terrorism Model. We then estimate the critical risk reduction, which is the risk‐reducing effectiveness of WHTI‐L needed for its benefit, in terms of reduced terrorism loss in the United States, to exceed its cost. Our analysis indicates that the critical risk reduction depends strongly not only on uncertainties in the terrorism risk level, but also on uncertainty in the cost of regulation and how casualties are monetized. For a terrorism risk level based on the RMS standard risk estimate, the baseline regulatory cost estimate for WHTI‐L, and a range of casualty cost estimates based on the willingness‐to‐pay approach, our estimate for the expected annualized loss from terrorism ranges from $2.7 billion to $5.2 billion. For this range in annualized loss, the critical risk reduction for WHTI‐L ranges from 7% to 13%. Basing results on a lower risk level that results in halving the annualized terrorism loss would double the critical risk reduction (14–26%), and basing the results on a higher risk level that results in a doubling of the annualized terrorism loss would cut the critical risk reduction in half (3.5–6.6%). Ideally, decisions about terrorism security regulations and policies would be informed by true benefit‐cost analyses in which the estimated benefits are compared to costs. Such analyses for terrorism security efforts face substantial impediments stemming from the great uncertainty in the terrorist threat and the very low recurrence interval for large attacks. Several approaches can be used to estimate how a terrorism security program or regulation reduces the distribution of risks it is intended to manage. But, continued research to develop additional tools and data is necessary to support application of these approaches. These include refinement of models and simulations, engagement of subject matter experts, implementation of program evaluation, and estimating the costs of casualties from terrorism events.  相似文献   
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