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基于知识图谱的管理学理论前沿分析 总被引:1,自引:0,他引:1
管理学(management)是研究管理活动基本问题的学科。在科学学科演进发展史上,管理学是一门较为活跃的学科,其理论不断翻新,层出不穷。以10种管理学代表性期刊所载论文的引文数据为分析对象,运用作品共被引、关键词共现和科学知识图谱方法,揭示管理学依次形成的三大主导理论——组织行为理论、组织结构理论和战略管理理论,并确认了当前的学科理论前沿。 相似文献
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Sampled-data control for time-delay systems 总被引:1,自引:0,他引:1
The sampled-data systems are hybrid ones involving continuous time and discrete time signals, which makes the traditional analysis and synthesis methodologies of time-delay systems unable to be directly used in the cases of hybrid systems with time-delay. The primary disadvantages of current design techniques of sampled-data control are their inabilities to deal effectively with time-delay and the model uncertainty. In this paper, we generalized the analysis methodology of time-delay systems to that of the hybrid systems with time-delay and uncertainty, which developed a design procedure of sampled-data control for time-delay systems. Asymptotic stability of the time-delay hybrid systems was developed. The time-delay dependent robust sampled-data control for the time-varying delay of an uncertain linear system was then discussed. The results were described as linear matrix inequalities, which can be solved using newly released LMITool. 相似文献
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Bibliometric maps of field of science 总被引:2,自引:1,他引:2
Irina Marshakova-Shaikevich 《Information processing & management》2005,41(6):1534-1547
The present paper is devoted to two directions in algorithmic classificatory procedures: the journal co-citation analysis as an example of citation networks and lexical analysis of keywords in the titles and texts. What is common to those approaches is the general idea of normalization of deviations of the observed data from the mathematical expectation. The application of the same formula leads to discovery of statistically significant links between objects (journals in one case, keywords — in the other). The results of the journal co-citation analysis are reflected in tables and map for field “Women’s Studies” and for field “Information Science and Library Science”. An experimental attempt at establishing textual links between words was carried out on two samples from SSCI Data base: (1) EDUCATION and (2) ETHICS. The EDUCATION file included 2180 documents (of which 751 had abstracts); the ETHICS file included 807 documents (289 abstracts). Some examples of the results of this pilot study are given in tabular form . The binary links between words discovered in this way may form triplets or other groups with more than two member words. 相似文献
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Towards all-author co-citation analysis 总被引:3,自引:0,他引:3
The present study examines one of the fundamental aspects of author co-citation analysis (ACA): the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting: on the one hand, the traditional type that only counts the first one among a cited work’s authors, and on the other hand, a simplified approach to all-author co-citation counting that takes into account the first five authors of a cited work. Results indicate that the picture produced through this simplified all-author co-citation counting contains author groups that are more coherent, and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed. Variations of counting more than first authors are compared. 相似文献
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复合图书馆的含义、原型及对我们的启示 总被引:27,自引:0,他引:27
复合图书馆强调对印刷型资源和电子资源实行整合,为用户提供集成化的检索服务,通过统一界面一次无缝地检索各种资源。目前,这种复合图书馆原型已经出现,为我们探索网络环境下的文献信息服务和数字图书馆建设提供了有益的借鉴。 相似文献
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随着电网规模的日趋扩大,传统的机电暂态或者电磁暂态仿真软件在分析电网的运行特性时,已开始显露出各自的局限性。将两者联合起来进行混合仿真,可以较好的解决仿真的规模、速度和精度的协调问题。在分析机电暂态和电磁暂态各自的特点的基础上,文中介绍了两者接口的原理和所涉及的问题。最后,对现有的三种混合仿真的接口时序方法进行了对比分析。 相似文献
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农业碳排放研究进展:基于CiteSpace的文献计量分析 总被引:1,自引:0,他引:1
基于Web of Science的SCI-EXPANDED与SSCI数据库数据,运用Cite SpaceⅢ软件对农业碳排放研究文献进行共被引聚类分析、关键节点分析以及突现词分析,以期发掘农业碳排放领域的研究前沿及其演进趋势。结果表明:(1)农业碳排放文献呈逐年递增趋势,属于生态环境与农业的交叉学科。(2)农地/土壤碳排与碳汇研究、农业生产非CO2类温室气体排放研究、农产品碳足迹研究以及土地利用变化的碳排与碳汇效应研究是主要的前沿主题。(3)农业碳排放领域的前沿演进有相对明显的脉络可循,对农地/土壤碳排与碳汇的研究从实验研究与情境研究发展至综合已有测算数据或者说已有知识的元分析,然后是基于过程模型的模型化研究(例如脱氮分解模型,DNDC)。(4)基于生命周期分析法的农产品碳足迹、气候变化背景下粮食安全问题与生物炭运用在近两年呈现高度突现,是后续学术研究需要重点关注的领域。 相似文献
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以汽油为动力的汽车对环境造成了大量的污染,新型节能环保汽车成为当前的研究热点,本位以PLC为控制器,设计风、光和电为能源动力的助力汽车,适用于城市的日常交通和可控范围里程的长途。文章主要研究混合动力汽车的结构设计、电路设计以及部分程序设计,为混合动力汽车设计提供参考。 相似文献