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101.
间歇过程多杂质用水网络的研究 总被引:1,自引:0,他引:1
对含有多个杂质的间歇用水网络进行综合研究,提出了用水周期的概念,基于不失问题的内在特性原则,提出了模型简化的基本假设,并通过增加中间储罐来跨过时间约束,提出了基于超结构的多杂质用水网络模型,建立了该超结构模型的数学规划模型;提出了该数学模型的分步求解策略:①不考虑时间约束,将看成1个拟连续过程,获得间歇用水的目标网络;②引入时间约束,调整间歇用水网络结构,优化未稳定用水单元,向目标网络逼进;③最终获得最优的间歇用水网络结构.实例研究表明,本文提出的方法是问歇过程多杂质用水网络结构设计的有效工具,可在较少周期后获得稳定的网络结构,新鲜水用量可节省34.9%. 相似文献
102.
无证书广义指定多个验证者有序多重签名 总被引:2,自引:0,他引:2
有序多重签名方案一般都是基于离散对数或身份的,存在着证书管理问题或是密钥托管问题。广义指定多个验证者签名体制允许签名的持有者指定多个签名的验证者,只有被指定的验证者可以验证签名的有效性。将无证书签名体制和广义指定多个验证者签名体制相结合,提出了无证书广义指定多个验证者有序多重签名方案及其安全模型。在随机预言模型下的安全性分析表明:该方案可以抵抗适应性选择消息攻击,其不可伪造性基于BDH困难假设。 相似文献
103.
Zhixue Wu 《Structural and Multidisciplinary Optimization》2009,37(6):625-634
The goal of this work is to obtain optimal hole shape for minimum stress concentration in two-dimensional finite plates using
parameterized geometry models. The boundary shape for a hole is described by two families of smooth curves: one is a “generalized
circular” function with powers as two parameters; the other one is a “generalized elliptic” function
a and b are ellipse axes) with powers as two parameters and one of the ellipse axes as the third parameter. Special attention is
devoted to the practicability of parameterized equations and the corresponding optimal results under the condition with and
without the curvature radius constraint. A number of cases were examined to test the effectiveness of the parameterized equations.
The numerical examples show that extremely good results can be obtained under the conditions with and without curvature radius
constraint, as compared to the known solutions in the literature. The geometries of the optimized holes are presented in a
form of compact parametric functions, which are suitable for use and test by designers. It is anticipated that the implementation
of the suggested parameterized equations would lead to considerable improvements in optimizing hole shape with high quality. 相似文献
104.
This paper investigates the theoretical justification of intelligent digital redesign (IDR) methods based on the approximate discrete-time models. Its main purpose is to design the digital fuzzy controller achieving the minimum norm distance between the trajectories of the approximate closed-loop systems under the analog and the digital controls. It is verified that, if there exist the digital gains such that the approximate norm distance is sufficiently small, the redesigned controller makes the trajectories of the exact closed-loop systems close, or, at least, asymptotically stabilizes the plant. 相似文献
105.
Surface reconstruction via geodesic interpolation 总被引:1,自引:0,他引:1
106.
107.
108.
海防视频监控系统中运动目标跟踪的设计与实现 总被引:2,自引:1,他引:1
针对海防视频监控系统中运动目标跟踪的问题,本文提出了利用上位机软件进行目标跟踪的设计与实现方案。文章首先介绍了海防视频监控系统的总体组成及工作流程;然后阐述了相关跟踪算法与金字塔分层搜索算法的实现,以及利用序贯相似检测算法与金字塔算法相结合的目标检测方法;最后描述了用目标偏移量对云台进行控制实现自动跟踪
踪的过程。通过在实际海防视频监控系统中的应用,对运动目标跟踪实现方案的有效性、实时性等特性进行了验证。 相似文献
踪的过程。通过在实际海防视频监控系统中的应用,对运动目标跟踪实现方案的有效性、实时性等特性进行了验证。 相似文献
109.
Mauro Bisiacco 《Multidimensional Systems and Signal Processing》1995,6(3):189-222
The infinite horizon optimal control problem is solved for 2D systems described by the Fornasini-Marchesini model. An 2-approach permits us to reduce the optimal control problem to a norm minimization one in Hilbert spaces. Both necessary and sufficient conditions for solvability and the structure of the solution are established. Moreover, a comparison with known results is presented, and the singularities of the 2D Riccati equation are examined in order to characterize suboptimal control laws that apply whenever the solvability conditions are not satisfied. 相似文献
110.
For networked sensor systems (NSSs) with hard and soft sensors including five uncertainties, two universal approaches of solving the robust fusion estimation problems are presented. It includes an integrated sequential covariance intersection (SCI) fusion minimax robust Kalman filtering approach with cross-covariance information and a generalized Lyapunov equation approach with four pairs of Lyapunov equations. Applying them, the robust local and SCI fused time-varying and steady-state Kalman filters are presented in the sense that their actual estimation error variances are guaranteed to have the corresponding minimal upper bounds. The equivalent batch SCI fusers are also presented. Their robustness and accuracy relations are proved, and the sensitivity of the SCI fuser with respect to the fused orders of sensors is analyzed. Applying the dynamic error system analysis method and the dynamic variance error system analysis method, a new convergence and absolute asymptotic stability theory of robust fusion Kalman filtering is presented. The classical Kalman filtering convergence and stability theory is developed. Compared with the original covariance intersection fuser, they significantly reduced the computational complexity and burden. Compared with the optimal and conservative SCI fusers, they significantly improved the robust accuracies. They are suitable to deal with asynchronous or random delayed data and are suitable for real-time applications. A simulation applied to the two-mass spring damper mechanical system shows their effectiveness. 相似文献