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41.
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
42.
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
43.
杨利军 《西南交通大学学报(社会科学版)》2008,9(4):94-100
在加德纳的多元化智能理论指导下,从学生个性发展、教材层面、教师授课角度、学生语言接受能力等方面对外语戏剧节对学生的影响进行观察性描述,通过抽样调查,可以得出结论:外语戏剧节对英语专业学生的间接影响主要体现在提高学习自信心、增强学习动机上;戏剧节对英语专业学生的直接影响,更多表现在对班级文化和身份的积极建塑上. 相似文献
44.
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
45.
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
46.
基于旅西日本游客旅游选择行为的西安旅游市场分析 总被引:1,自引:0,他引:1
根据在全国六大旅游热点城市所做的旅游市场调查的数据结果,对旅西日本游客的旅游选择行为进行了研究,同时进一步有针对性地对西安日本客源市场进行了SWOT分析,在此基础上,对西安旅游业的发展提出了相关对策建议。 相似文献
47.
潜在客户资产测量研究 总被引:1,自引:0,他引:1
客户资产由当前客户资产和潜在客户资产两部分组成,对潜在客户资产测量问题尚未有系统的研究。在客户购买行为建模研究的基础上,提出由客户获取预测分析、客户购买行为分析和客户费用分析组成的潜在客户资产测量方法框架,总结了可用的模型,并用实证案例说明;提出利用当前潜在客户资产分析矩阵分析指导投资和管理决策的方法。 相似文献
48.
用三点弯曲(TPB)裂纹试件测定平面应变条件下的断裂韧性J1c与JR,试验结果表明,稀土Ce较大地提高了Al-Mg-Si合金的起裂韧度值J1c,特别是,显著地改善了合金的裂纹扩展抗力JR。金相显微观察和电镜分析表明,稀土Ce改善了材料的初始细观结构(材料在加载前的组织结构),改变了材料的细观损伤特点,发展了材料的含损伤塑性。 相似文献
49.
This report summarizes the proceedings of a conference on quantitative methods for assessing the risks of developmental toxicants. The conference was planned by a subcommittee of the National Research Council's Committee on Risk Assessment Methodology 4 in conjunction with staff from several federal agencies, including the U.S. Environmental Protection Agency, U.S. Food and Drug Administration, U.S. Consumer Products Safety Commission, and Health and Welfare Canada. Issues discussed at the workshop included computerized techniques for hazard identification, use of human and animal data for defining risks in a clinical setting, relationships between end points in developmental toxicity testing, reference dose calculations for developmental toxicology, analysis of quantitative dose-response data, mechanisms of developmental toxicity, physiologically based pharmacokinetic models, and structure-activity relationships. Although a formal consensus was not sought, many participants favored the evolution of quantitative techniques for developmental toxicology risk assessment, including the replacement of lowest observed adverse effect levels (LOAELs) and no observed adverse effect levels (NOAELs) with the benchmark dose methodology. 相似文献
50.
作者运用理论分析和实证分析相结合的方法对佛山市经济发展的实践予以深刻剖视后指出:佛山市经济建设处在从物质投入主导型向科技进步主导塑转变的转折点上,在跨世纪的经济发展与经济竞争中,佛山市必须实行科技兴市的新发展战略,作者对佛山市科技兴市战略的涵义,目标,条件作了深入分析,并进而设计了科技兴市战略的运行机制和政策落点。 相似文献