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21.
Does social capital as resources of network members affect health information search? Analyzing data from the 2004 General Social Survey in the United States, this study measures two social capital indicators (average education of network members and proportion of network members with a high school degree or higher) using the name generator. Most results are consistent using those two indicators. Both indicators are positively associated with frequency of health information seeking and seekers’ frequency of use of two sources (friends or relatives and the Internet). Also average education of network members is positively associated with seekers’ diversity of used sources and frequency of consultation with medical professionals. But neither indicator is associated with seekers’ frequency of use of other four sources (health-related magazines or newsletters, general magazines, daily newspapers, and radio or television programs). The findings demonstrate the theoretical utility of social capital in the social dynamics of medical help-seeking.  相似文献   
22.
This paper presents a method for using end-to-end available bandwidth measurements in order to estimate available bandwidth on individual internal links. The basic approach is to use a power transform on the observed end-to-end measurements, model the result as a mixture of spatially correlated exponential random variables, carryout estimation by moment methods, then transform back to the original variables to get estimates and confidence intervals for the expected available bandwidth on each link. Because spatial dependence leads to certain parameter confounding, only upper bounds can be found reliably. Simulations with ns2 show that the method can work well and that the assumptions are approximately valid in the examples.  相似文献   
23.
Many education systems are developing towards more lateral structures where schools collaborate in networks to improve and provide (inclusive) education. These structures call for bottom-up models of network evaluation and accountability instead of the current hierarchical arrangements where single schools are evaluated by a central agency. This paper builds on available research about network effectiveness to present evolving models of network evaluation. Network effectiveness can be defined as the achievement of positive network level outcomes that cannot be attained by individual organizational participants acting alone. Models of network evaluation need to take into account the relations between network members, the structure of the network, its processes and its internal mechanism to enforce norms in order to understand the achievement and outcomes of the network and how these may evolve over time. A range of suitable evaluation models are presented in this paper, as well as a tentative school inspection framework which is inspired by these models. The final section will present examples from Inspectorates of Education in Northern Ireland and Scotland who have developed newer inspection models to evaluate the effectiveness of a range of different networks.  相似文献   
24.
Recent studies have paid more attention to how position-generated social capital varies by an individual’s characteristics, and less to how geographical distributions of occupations may constrain position-specific connections. By integrating two national surveys from the United States, we differentiate the extent to which individual social capital fluctuates by occupational compositions at the county, metropolis, and state levels. Multilevel analyses show that when more people at all three levels work in education, training, and library occupations, residents have a greater chance to gain access to professional-type resources. Similar spatial effects on farming and production resources, however, are more apparent at the county level. Not only does the association between individual social capital and local occupational structures vary across different occupations, but the magnitude of such spatial effects also differs by the scope of the geographical areas. The findings underscore how contextual factors and geographical location may contribute to building occupation-specific network resources.  相似文献   
25.
在我国能源安全面临的一系列重大问题中,能源领域的政策规划薄弱,法律保障制度建设与管理体制改革滞后,能源供应与能源安全保障体系缺乏相关政策、法律和制度的保障。只有真正做到政策、法律和管理体制“三位一体”,才能确保国家能源安全。本文从能源安全体系建构的理论和实践出发,借鉴西方能源安全战略实践,从政策、法律和管理体制等角度,对我国能源安全体系的内在机制建构进行分析,旨在为我国与中东能源合作提供借鉴与参考。  相似文献   
26.
杨蕙馨  张红霞 《统计研究》2020,37(10):66-78
基于增加值和最终产品的生产分解模型,本文对我国制造业前向与后向产业关联下的全球价值链嵌入进行测度,实证分析全球价值链嵌入对技术创新的作用机理,并在此基础上重点探讨了吸收能力与技术差距两个重要情境因素的调节作用,同时,运用双重差分、工具变量法以及GMM动态面板模型进行稳健性检验,以控制潜在的内生性问题。研究发现:①我国制造业通过嵌入全球价值链的国际间知识溢出效应促进技术创新能力的提升;②吸收能力能够强化这一正向影响关系;③技术差距在后向全球价值链嵌入对技术创新的影响关系中呈倒U 型调节作用,而在前向全球价值链嵌入对技术创新的影响关系中呈正向调节作用。本文推动了网络嵌入理论和知识溢出理论从组织网络向全球价值链领域的繁衍,丰富了全球价值链嵌入领域的研究成果,同时为我国制造业企业在参与国际分工过程中利用全球价值链嵌入实现技术创新能力提升提供重要的理论参考。  相似文献   
27.
网络生态伦理哲学基础与高校德育方法论   总被引:2,自引:0,他引:2  
网络在给大学生提供信息便利的同时,也导致了他们自我约束力和道德法制意识的降低.而建立在因特网基础上的网络文化,也冲击着人类建立在现代化基础上的现代教育,使人们更加关注网络生态伦理问题.在网络生态环境下,高校应把"以学生为本"作为高校德育方法论的逻辑起点和价值取向,以"道德审美"作为高校德育方法论,以建构和谐的大学生网络生态伦理文化.  相似文献   
28.
试析中国与沙特阿拉伯的石油合作   总被引:1,自引:0,他引:1  
沙特阿拉伯是世界第一大原油生产国和出口国,中国是世界第二大石油消费国和消费量增长最快的石油进口国.沙特需要为其巨大的能源储量寻找新的市场,中国需要海外能源满足经济增长的需要.因此,两国在能源领域存在着相互依赖关系.正是这种相互依赖关系推动着中沙关系的稳步发展,本文力图运用政治经济学的分析法对中沙石油合作做出理性分析与判断.  相似文献   
29.
Nowadays, many wicked problems such as environmental issues require organizations from multiple sectors to form cross-sectoral alliances. Cross-sectoral alliance networks can transfer resources and signal affiliations and value alignment between strategic partners. The communication of cross-sectoral alliances is a form of CSR communication that serves organizations’ strategic goals and objectives. Drawing on the literature on digital CSR communication and legitimacy theory, this article examines which legitimacy needs shape the formation of cross-sectoral ties on Facebook in addressing environmental and sustainable development issues in the United States. Combining data-mining, text-mining, social network analysis, and exponential graph modeling, this research investigates the structure of a network among 3071 organizations across multiple sectors. Findings show that organizations’ cross-sectoral tie formation is mainly driven by social legitimacy and alliance legitimacy needs.  相似文献   
30.
宁瀚文  屠雪永 《统计研究》2019,36(10):58-73
波动率是金融风险管理研究的重要内容之一。本文基于复杂网络理论和数据挖掘技术提出股票市场的高维波动率网络模型。首先运用互信息度量不同股票价格波动之间的相关关系,其次对股票市场不同周期下的波动情况建立度的中心势、平均距离、幂律分布等网络拓扑指标,再次根据这些指标利用Prim算法构建出高维波动率网络模型,最后运用Newman-Girvan算法对股票价格波动率的相关性进行分层研究。高维波动率网络模型突破了传统波动率模型关于变量维数的限制,能够在依赖少量假设的基础上,挖掘出多个金融市场主体间的相互关系,反映金融市场的风险特征及网络拓扑性质。实证结果发现:与常用的Pearson相关系数法相比,在互信息框架下,股价波动的非线性相关关系得到了更好的度量;股票市场的整体波动性与个股波动率相关性变化趋势相反,市场处在高波动时期资产组合分散化效果较好;网络中存在少量度数大的关键节点和中心节点,风险通过这些节点可以迅速传递到整个市场;股票市场的运行具有明显的行业聚集现象;网络分层研究进一步直观的展现了风险在层与层之间的传递规律和与之对应的行业特征。高维波动率网络模型为挖掘股票市场的风险特征与管理金融风险提供了一个新的工具。  相似文献   
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