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91.
选取制造业的十个重点行业,使用2001-2014年的面板数据,运用数据包络分析法(DEA)对其产能利用率、技术效率和设备利用率进行了测算,结果显示:我国制造业的部分行业存在严重的产能过剩问题;非金属矿物制品业、黑色金属冶炼和压延加工业等传统行业的产能利用率较低;通信设备、计算机及其他电子设备制造业等新兴行业的产能利用率相对较高.剖析制造业产能过剩的影响因素,发现市场需求与产能利用率存在显著的正相关关系,资本密集度、就业水平、开放度、金融支持与产能利用率有显著的负相关关系. 相似文献
92.
黄贤忠 《重庆文理学院学报》2018,37(5):70-76
对大学生国学认知程度和需求的调查是有效开展国学教育的基础。这个基础必须通过详实的数据调查和实证分析来奠定。通过在某高校展开问卷调查,我们发现大学生对于国学的不甚了解是一个普遍现象。高校学生对国学教育的需求不仅存在,而且是理性而合理的。真正影响高校国学教育效果的症结仍然是师资力量、课程内容、教学步骤等问题。我们建议应该遵循由易到难、从日常习用到弘文奥义、分类教学的原则,系统地做好国学教育内容的顶层设计。 相似文献
93.
对大数据和企业精准营销相关性的分析能够为精准营销的实施提供基础和技术平台,为企业对大数据的管理提供一定的方向,将很大程度影响企业的竞争力和发展。在拟定大数据和精准营销指标体系基础上,通过对黑龙江省服务业、商业企业、制造业和现代农业企业进行问卷调查,运用结构方程模型分析其相关性。分析结果显示,大数据与精准营销具有显著相关性,客户数据挖掘对大数据具有显著影响,精准广告投放对精准营销具有显著影响。据此指出,企业应当充分利用大数据技术,注重客户数据挖掘,提高营销的精准性,使其能适应市场竞争带来的机遇与挑战。 相似文献
94.
Accurate forecast of the carbon trading price is of great significance in promoting the scientific and rational development of carbon trading market. Therefore, this paper proposes a multi-scale combined forecasting method for carbon price based on mixed structure data. First, the Google Index is used to extract the unstructured data related to the carbon price.The dimensions of unstructured data are reduced based on principal component analysis. Then, EMD is employedto the structured data,unstructured data and the carbon trading price to obtain different IMFs, which are reconstructed by the Fine-to-Coarse technique to get low, high frequency sequence and trend sequence. Furthermore, the three items are predicted respectively by using ARIMA, PLS and neural networks according to the features of each scale in time series. Finally, the forecasting results are summed to get the carbon price forecast sequence. The proposed method is used to forecast carbon price in EU. The empirical results show that the prediction accuracy of the model is higher than that of the single prediction method and the prediction method that time series aren’t decomposed by EMD, which is of great applicability. 相似文献
95.
中国省域碳排放的空间特征及影响因素 总被引:1,自引:0,他引:1
通过核密度分布和莫兰指数对中国2000—2015年30省份碳排放强度的动态趋势及集聚特征进行测度,并利用空间杜宾模型对其主要影响因素进行分析。结果显示:(1)中国30省份碳排放强度呈下降趋势,新常态以来低碳步伐加快;(2)碳排放强度的空间集聚性具有高水平集中、低水平集聚特征,空间溢出效应不断增强;(3)本省经济规模、产业结构对本省碳排放强度具有显著的正向影响,专利产出具有显著的负向影响;相邻省份的外商投资规模及能源消费结构变化对本省碳排放具有显著的空间溢出作用。因此,未来中国加快产业结构调整幅度、优化相邻省份间的产业空间布局以及大力发展绿色技术进步是中国促进区域低碳转型的主要方向,同时生态城镇化以及继续改善外商直接投资质量也是减排潜力因子,省域间的减排空间溢出效果不容忽视。 相似文献
96.
如何应用大数据提升国防动员潜力调查的效率是当前政府重点关注的话题。从国防动员潜力大数据的定义和特征着手,分析大数据下国防动员潜力调查所具备的优势,发现仍然存在思维局限、指标不统一、体制不健全、技术缺乏及数据共享与防护难协同等困境。通过思维意识、管理体制、指标体系、核心技术、专业人才、安全共享等六大模块,打破“数据不可用、数据不会用”的现实瓶颈,实现整合国防动员数据资源、延展数据内容和提高工作效率的目标。 相似文献
97.
郭宁 《上海理工大学学报(社会科学版)》2018,40(1):77-80
有效数字是大学化学实验课程的主要教学内容之一,是培养学生在课程中理解并在日常学习与工作中规范使用有效数字,提升其对有效数字与测定误差之间关系的认识水平,树立良好规范的数字记录习惯,具有十分重要的现实意义。论述介绍了目前大学化学实验教学中关于有效数字方面存在的主要问题,并采用相应的举措建立和完善了教学方案以利于更好地解决存在的问题。通过几个学期的教学实践发现新教学方案取得了初步的成效,同时严格按照有效数字的要求记录与计算数据也是培养学生具有严谨科学素养的一条重要途径。 相似文献
98.
Jessica Pineda-Zumaran 《Planning Practice and Research》2016,31(3):270-291
Spatial thinking and spatial knowledge generation in decision-making are still not mature fields of study in planning research, despite these being crucial elements in addressing the issues of the twenty-first-century city. This article contributes to their understanding by exploring their interrelationships with spatial data usage. Through storylines, it analyzes the arguments that planning practitioners offer in support of infrastructure-led decisions in Arequipa (Peru), before and after spatial data usage. The article concludes that spatial data usage improve spatial thinking to different extents, yet suggests aligning spatial data generation and the inclusion of GIS-based spatial analyses with the spatial knowledge needed by routine planning practice. 相似文献
99.
Consider a two-by-two factorial experiment with more than one replicate. Suppose that we have uncertain prior information that the two-factor interaction is zero. We describe new simultaneous frequentist confidence intervals for the four population cell means, with simultaneous confidence coefficient 1 ? α, that utilize this prior information in the following sense. These simultaneous confidence intervals define a cube with expected volume that (a) is relatively small when the two-factor interaction is zero and (b) has maximum value that is not too large. Also, these intervals coincide with the standard simultaneous confidence intervals obtained by Tukey’s method, with simultaneous confidence coefficient 1 ? α, when the data strongly contradict the prior information that the two-factor interaction is zero. We illustrate the application of these new simultaneous confidence intervals to a real data set. 相似文献
100.
A Bayesian Model and Stochastic Exposure (Dose) Estimation for Relative Exposure Risk Comparison Involving Asbestos‐Containing Dropped Ceiling Panel Installation and Maintenance Tasks
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Assessing exposures to hazards in order to characterize risk is at the core of occupational hygiene. Our study examined dropped ceiling systems commonly used in schools and commercial buildings and lay‐in ceiling panels that may have contained asbestos prior to the mid to late 1970s. However, most ceiling panels and tiles do not contain asbestos. Since asbestos risk relates to dose, we estimated the distribution of eight‐hour TWA concentrations and one‐year exposures (a one‐year dose equivalent) to asbestos fibers (asbestos f/cc‐years) for five groups of workers who may encounter dropped ceilings: specialists, generalists, maintenance workers, nonprofessional do‐it‐yourself (DIY) persons, and other tradespersons who are bystanders to ceiling work. Concentration data (asbestos f/cc) were obtained through two exposure assessment studies in the field and one chamber study. Bayesian and stochastic models were applied to estimate distributions of eight‐hour TWAs and annual exposures (dose). The eight‐hour TWAs for all work categories were below current and historic occupational exposure limits (OELs). Exposures to asbestos fibers from dropped ceiling work would be categorized as “highly controlled” for maintenance workers and “well controlled” for remaining work categories, according to the American Industrial Hygiene Association exposure control rating system. Annual exposures (dose) were found to be greatest for specialists, followed by maintenance workers, generalists, bystanders, and DIY. On a comparative basis, modeled dose and thus risk from dropped ceilings for all work categories were orders of magnitude lower than published exposures for other sources of banned friable asbestos‐containing building material commonly encountered in construction trades. 相似文献