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941.
从CALIS到CADLIS--"中国高等教育数字化图书馆"建设项目正式启动 总被引：7，自引：1，他引：6
总结了中国高等教育文献保障体系(CALIS)“九五”阶段的建设成果和经验,“十五”建设项目由CALIS二期工程和中英文图书数字化国际合作计划(CADAL)两个专题组成,名称调整为“中国高等教育文献保障体系——中国高等教育数字化图书馆”(CADLIS),指出了其建设目标、建设内容和任务。 相似文献
942.
国内外信息管理研究的流派与研究框架 总被引：1，自引：0，他引：1
在对国内外信息管理研究中关于信息管理概念的不同提法进行综述和分析的基础上,依据研究体系、范畴、对象的不同特点,将当前的信息管理研究划分为四个不同的流派,并分别对他们的研究框架进行了归纳总结和剖析。最后,对信息管理领域新的研究方向作出了展望。 相似文献
943.
In this paper, the optimal synchronization controller design problem for complex dynamical networks with unknown system internal dynamics is studied. A necessary and sufficient condition on the existence of the optimal control minimizing a quadratic performance index is given. The optimal control law consists of a feedback control and a compensated feedforward control, and the feedback control gain can be obtained by solving the well-known Algebraic Riccati Equation (ARE). Especially, in the presence of unknown system dynamics, a novel adaptive iterative algorithm using the information of system states and inputs is proposed to solve the ARE to get the optimal feedback control gain. Finally, a simulation example shows the effectiveness of the theoretical results. 相似文献
944.
Shenghui Guo Bin Jiang Fanglai Zhu Qingbin Gao 《Journal of The Franklin Institute》2019,356(18):11741-11759
In this paper, the problem of state and unknown input estimations for a class of discrete-time switched linear systems with average dwell time switching is investigated. First, a proportional integral observer with an exponential H∞ performance is constructed to estimate the system state and unknown input simultaneously. Second, both of the observability and the stability of the estimation error system are analyzed, then the derivation of the observer gain matrices is transformed into the calculation of linear matrix inequalities. Third, the obtained results are extended to the systems with output disturbances. Finally, two simulation examples are provided to show the validity and effectiveness of the proposed methods. 相似文献
945.
In this paper, a complete procedure for the study of the output regulation problem is established for a class of positive switched systems utilizing a multiple linear copositive Lyapunov functions scheme. The feature of the developed approach is that each subsystem is not required to has a solution to the problem. Moreover, two types of controllers and switching laws are devised. The first one depends on the state together with the external input and the other depends only the error. The conditions ensuring the solvability of the problem for positive switched systems are presented in the form of linear matrix equations plus linear inequalities under some mild constraints. Two examples are finally given to show the performance of the proposed control strategy. 相似文献
946.
Research and development (R&D) is often essential for firms’ profitability and growth. At the same time, R&D is long-term and risky. We show that innovation activities lead to information ambiguity about the future value of firms’ assets. This effect appears to be more pronounced for small and less reputed firms. Information ambiguity further lowers firms’ market value and, in particular, the market value of innovative assets. We further show that high quality patents mitigate the negative effect of information ambiguity to some extent. 相似文献
947.
Participation in and adding content to social tagging tools is important for these tools to achieve their purpose of classifying and organizing information. Users of social tagging tools are driven to participate and add tags by extrinsic and intrinsic motivation. Extrinsic motivation is dominating research as a main predictor of why users use information systems. Social tagging tools, as a subset of social media tools, are distinguished by their unique social aspect that makes intrinsic motivation a potential driver for users to add tags to content. Intrinsic motivation, when applied to social tagging tools, could entail many shades that represent different users’ motives for using such tools. In this paper, we add a rich concept of intrinsic motivation to include hedonism as a main predictor of users’ behavior on social tagging tools. We empirically validate a previously proposed theoretical model of three dimensional concepts of hedonism with three components describing individuals’ hedonic state when interacting with social tagging tools: explorability, curiosity, and enjoyment. After a robust and thorough data analysis using structured equation modeling, the results confirm our theoretical model and suggest using a richer concept of enjoyment to reflect a hedonic dimension when investigating intrinsic motivation with interactive social media tools. Our validated model could be the spark of new factors that have the potential to influence user acceptance of information systems in general and in social media tools. This research contributes to the development of attitude-behavior theories that could explain users’ acceptance of dynamic web 相似文献
948.
Smart cities employ information and communication technologies to improve: the quality of life for its citizens, the local economy, transport, traffic management, environment, and interaction with government. Due to the relevance of smart cities (also referred using other related terms such as Digital City, Information City, Intelligent City, Knowledge-based City, Ubiquitous City, Wired City) to various stakeholders and the benefits and challenges associated with its implementation, the concept of smart cities has attracted significant attention from researchers within multiple fields, including information systems. This study provides a valuable synthesis of the relevant literature by analysing and discussing the key findings from existing research on issues related to smart cities from an Information Systems perspective. The research analysed and discussed in this study focuses on number of aspects of smart cities: smart mobility, smart living, smart environment, smart citizens, smart government, and smart architecture as well as related technologies and concepts. The discussion also focusses on the alignment of smart cities with the UN sustainable development goals. This comprehensive review offers critical insight to the key underlying research themes within smart cities, highlighting the limitations of current developments and potential future directions. 相似文献
949.
950.