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861.
862.
本文介绍了目前高炉渣处理、回收利用的现状,提出了热量回收问题的新方法。高炉渣干法新技术有望解决其渣粒化及热量回收的问题,是高炉渣处理利用的发展趋势。 相似文献
863.
In this paper, the quadratic minimax optimal control of linear system with input-dependent uncertainty is studied. We show that it admits a unique solution and can be approximated by a sequence of finite-dimensional minimax optimal parameter selection problems. These finite-dimensional minimax optimal parameter selection problems are further reduced to scalar optimization problems which also admit unique solutions. Thus, the original minimax optimal control problem is solved via solving a sequence of simple scalar optimization problems. Numerical experiments are presented to illustrate the developed method. 相似文献
864.
The design problem of collocated feedback controllers is addressed in this paper for a class of semi-linear distributed parameter systems described by parabolic partial differential equation (PDE), where a finite number of local actuators and sensors are intermittently distributed in space. A Lyapunov direct method for the exponential stability analysis of the resulting closed-loop system is first presented for the system, in which the first mean value theorem for integration and the Wirtinger's inequality are employed. The corresponding stabilization condition is then derived through the analysis result. Finally, the proposed design method is implemented on the feedback control of a fisher equation and its effectiveness is evaluated through simulation results. 相似文献
865.
The dominant understanding of Internet censorship posits that blocking access to foreign-based websites creates isolated communities of Internet users. We question this discourse for its assumption that if given access people would use all websites. We develop a conceptual framework that integrates access blockage with social structures to explain Web users’ choices, and argue that users visit websites they find culturally proximate and that access blockage matters only when such sites are blocked. We examine the case of China, where online blockage is notoriously comprehensive, and compare Chinese Web usage patterns with those elsewhere. Analyzing audience traffic among the 1000 most visited websites, we find that websites cluster according to language and geography. Chinese websites constitute one cluster, which resembles other such geolinguistic clusters in terms of both its composition and its degree of isolation. Our sociological investigation reveals a greater role of cultural proximity than access blockage in explaining online behaviors. 相似文献
866.
This paper investigates the generalized matrix projective synchronization problem of general colored networks with different-dimensional node dynamics. A general colored network consists of colored nodes and edges, where the dimensions of colored node dynamics can be different in addition to the difference of the inner coupling matrices between any pair of nodes. For synchronizing a colored network onto a desired orbit with respect to the given matrices, open-plus-closed-loop controllers are designed. The closed-loop controllers are chosen as adaptive feedback and intermittent controllers, respectively. Based on the Lyapunov stability theory and mathematical induction, corresponding synchronization criteria are derived. Noticeably, many existing synchronization settings can be regarded as special cases of the present synchronization framework. Numerical simulations are provided to verify the theoretical results. 相似文献
867.
868.
文章概述了空间科学与空间科学卫星的特点,具体阐述了其在科学上的前沿性,在空间技术和相关高技术上的带动性,以及对国家政治、外交、国防和社会发展的重要作用,介绍了中科院正在实施的空间科学先导专项在科学前沿、技术带动和国际影响方面预计的成果产出,并对其后续发展提出了建议。 相似文献
869.
公私合营的PPP模式能有效解决政府项目资金不足,其融资模式选择和评价成为重要问题。本文根据财务评价方法,提出项目融资方案的评价指标——项目融资效益。从政府角度出发,建立特许经营项目BOT和BOO两种模式的融资效益模型和计算步骤,以煤矿项目为例进行验算,结论表明BOT模式更适合此类项目。两种模式融资效益存在差异的原因在于分析立场和计算时间。论文研究的融资效益模型为各种特许经营项目融资方案综合评价提供重要指标和方法。研究结论可用于此类项目融资模式的选择、设计与优化。 相似文献
870.