首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   642篇
  免费   31篇
  国内免费   14篇
管理学   121篇
民族学   4篇
人口学   52篇
丛书文集   19篇
理论方法论   40篇
综合类   280篇
社会学   125篇
统计学   46篇
  2023年   16篇
  2022年   14篇
  2021年   12篇
  2020年   24篇
  2019年   18篇
  2018年   18篇
  2017年   23篇
  2016年   29篇
  2015年   27篇
  2014年   27篇
  2013年   90篇
  2012年   33篇
  2011年   40篇
  2010年   37篇
  2009年   37篇
  2008年   29篇
  2007年   29篇
  2006年   31篇
  2005年   24篇
  2004年   22篇
  2003年   15篇
  2002年   15篇
  2001年   11篇
  2000年   7篇
  1999年   10篇
  1998年   5篇
  1997年   6篇
  1996年   6篇
  1995年   9篇
  1994年   2篇
  1993年   3篇
  1992年   6篇
  1991年   3篇
  1990年   1篇
  1989年   2篇
  1988年   2篇
  1987年   3篇
  1981年   1篇
排序方式: 共有687条查询结果,搜索用时 15 毫秒
1.
根据机械振动和积木式传递矩阵法的原理,提出了用于估算单、双转子系统一阶临界转速的实用方法,从而得到的“K3表”可方便地使用于产品的方案设计阶段或现场排故,并可得到满意的工程精度。  相似文献   
2.
逆系统方法是以非线性控制为目的,以直接分析为途径,以动态系统的逆概念为核心。该文将逆系统方法应用于刚体动力学中,运用非线性控制的逆系统方法设计Euler动力学方程的控制器,通过对一个陀螺的外力矩进行实施控制,使刚体在动坐标系下的角速度稳定跟踪指令,来实现对刚体转动的渐进跟踪控制。  相似文献   
3.
李毅学  徐渝  唐方成 《管理工程学报》2007,21(2):142-144,137
外在制度在大群体组织中的实施是个复杂的过程.这一过程中,组织成员的理性程度较低而且行为相似,较适合用对称的模仿者动力学模型来分析.外在制度虽具有一定的自实施功能,但实施过程中实施者的主动性和创造性也很重要.借助于模型和案例分析,实施者可在现实中通过适当操作来控制实施环境,增强外在制度的实施效果.  相似文献   
4.
The Evolution of Knowledge and the Dynamics of an Industry Network   总被引:1,自引:0,他引:1  
The paper moves a step forward in the direction of establishing a connection between the structure and evolution of knowledge bases and the structure and evolution of organizational forms in innovative activities in a science-intensive industry. The paper has an explicit focus on the dynamics of the network of collaborative agreements in R&D in the pharma/biotech industry after the “molecular biology revolution”. Using a comprehensive dataset, built by the authors integrating several sources in the industry, the dynamics of the network over time is extensively analyzed. With regards to network structure, it is found that, while the size of the network increases over time due to net flows of entry, its topological properties remain relatively unchanged. The evolution of the network has occurred without relevant deformations in the core-periphery profile. With regards to age-dependent propensity to collaborate, the paper finds that the extent of inter-generational collaboration is much more significant than intra-generational collaboration. In addition, the propensity of firms of a given generation to enter into collaboration with firms of a different generation increases with the distance between the two, while the total number of intra-generational collaborations decreases over time and, moreover, tends to decrease for most recent generations. In the paper a unitary and coherent explanation of the evidence is developed, coming to reveal the existence of a striking isomorphism between structural properties of the dynamics of knowledge and of the evolution of network structure. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
5.
曾群华 《城市观察》2014,34(6):61-66
人口空间动态与区域经济发展的耦合关系是同城化区域间共同面对的重要课题。本文在解构人口空间动态维度主体的基础上,将人口空间动态的诉求机制与动因机理架构于更低交易费用的利益诉求之上,解析人口空间动态的模式选择,深入探讨人口空间动态与区域经济发展的耦合关联性。在此基础上,提出引导人口流动与合理分布的策略。研究成果将有助于更好地理解同城化态势下人口空间演变的动因机理,为同城区域的经济发展、城市规划、文化交融等方面的科学设计提供重要参考。  相似文献   
6.

This paper arises out of psychoanalytically oriented consultancy to teams of staff in the helping professions where there is a statutory 'duty to care'. It takes as its premise the seemingly paradoxical hypothesis that workers may need to split off part of their emotional experience in order to preserve their own mental health and provide reliable services to their clients. I argue that while a professional 'duty to care' requires us to be emotionally 'in touch', the demands of our clients together with the demands of the institutional response to the 'duty to care' cause us to split off parts of our awareness. I also argue that provided the splitting does not become extreme we are doing no more or less than the rest of society. In other words, there is a degree of 'normal splitting' which numbs our awareness of danger and destructiveness and seeks to protect us from too much anxiety and pain. Yet if professional workers are charged with the responsibility of assessing risk and acting accordingly for the protection of all concerned they need ways of being 'in touch' (re-integrating the splits) for some or enough of the time. Finally, I will describe ways of being 'in touch', illustrating the difficulty and the pain of re-integrating the splits and some of the insights that can arise out of this work with examples from my consultancy work.  相似文献   
7.
Group concept mapping (GCM) has been successfully employed in program planning and evaluation for over 25 years. The broader set of systems thinking methodologies (of which GCM is one), have only recently found their way into the field. We present an overview of systems thinking emerging from a system dynamics (SD) perspective, and illustrate the potential synergy between GCM and SD. As with GCM, participatory processes are frequently employed when building SD models; however, it can be challenging to engage a large and diverse group of stakeholders in the iterative cycles of divergent thinking and consensus building required, while maintaining a broad perspective on the issue being studied. GCM provides a compelling resource for overcoming this challenge, by richly engaging a diverse set of stakeholders in broad exploration, structuring, and prioritization. SD provides an opportunity to extend GCM findings by embedding constructs in a testable hypothesis (SD model) describing how system structure and changes in constructs affect outcomes over time. SD can be used to simulate the hypothesized dynamics inherent in GCM concept maps. We illustrate the potential of the marriage of these methodologies in a case study of BECOMING, a federally-funded program aimed at strengthening the cross-sector system of care for youth with severe emotional disturbances.  相似文献   
8.
朱莉  曹杰  顾珺  郑翼 《中国管理科学》2020,28(12):151-161
在以人道主义为本的应急救援活动中,不可忽视被救灾民和施救决策者们异质性行为的影响。一方面,将各灾民因救援物资需求未被及时满足而呈现的差异化心理痛苦度量成经济损失,并纳入应急救援调度的社会成本这一决策目标中;另一方面,在灾后物资调度决策中,关注具有异质性偏好的各应急决策者所展现出的不同救援态度。结合面向联合机会约束规划的动态供需平衡限制,最终构建一个考虑灾民和决策者们异质性行为的多阶段灾后救援物资分配和应急路径优化模型。采用2008年汶川地震为案例背景,应用遗传算法对模型求解和参数分析,将仿真结果与不考虑异质性行为的传统救援调度方案进行比较,得出一些结论为构建高效的应急救援体系提供有益参考。  相似文献   
9.
演化博弈论在中国法治政府研究中具有很好的适用性,可以据此构建“复制动态”的中国法治政府的演化博弈模型,证明“内生演化”的法治能够从根本上解决政府“权力悖论”。中国法治政府建设需要围绕约束规范公权力的主题,确立互动平衡精神和采取渐进主义策略,以改进转型中国的法治秩序。  相似文献   
10.
桥塞作为井下封层技术的关键设备,由于它施工工序少、周期短、卡封位置准确而得到了广泛应用。针对设计的可钻式非金属桥塞坐封过程开展模拟研究,涉及弹塑性材料接触、超弹性材料接触和非金属材料动态断裂的非线性动力学问题,利用有限元法建立该桥塞全尺寸模型和所有部件之间的广义接触关系,通过有限元模拟动态坐封过程获得桥塞各部件运动变形特性、桥塞与套管之间的密封特性和动态坐封力等数据,该桥塞坐封完成时,坐封机构部件轴向位移110 mm,坐封力约45 kN。模拟坐封也为进一步优化该型桥塞的结构和评估坐封性能提供了理论依据,对该型桥塞的推广应用奠定了基础。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号