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991.
This paper presents a performance analysis of discrete time periodically time varying controllers for the rejection of lp specific and uniform disturbances. Earlier results on l2 performance are extended to l1 and l∞ performance to present a unified treatment of lp performance for all p ε [1, ∞]. For a given linear time varying periodic controller, a linear time invariant controller is constructed and necessary and sufficient conditions are presented under which the linear time invariant controller gives strictly better lp disturbance rejection performance than the time varying periodic controller. 相似文献
992.
The refinement calculus is a well-established theory for formal development of imperative program code and is supported by a number of automated tools. Via a detailed case study, this article shows how refinement theory and tool support can be extended for a program with real-time constraints. The approach adapts a timed variant of the refinement calculus and makes corresponding enhancements to a theorem-prover based refinement tool. 相似文献
993.
三对角对称矩阵逆特征问题 总被引:6,自引:0,他引:6
In this paper, four inverse eigenproblems with giventhree eigenvalues and corresponding eigenvectors are considered, somenecessary and sufficient conditions under which there exists a uniquesolution for these problems are given. Furthermore some numerical algorithmsand some numerical experiments are given. 相似文献
994.
Re-engineering of the design process for concurrent engineering 总被引:20,自引:0,他引:20
Dunbing Tang Li Zheng Zhizhong Li Dongbo Li Shiqi Zhang 《Computers & Industrial Engineering》2000,38(4):479-491
According to the requirements of concurrent engineering, three interdependency relationships (uncoupled relationship, coupled relationship and decoupled relationship) between design activities are presented in this paper. And the coupled relationship plays an important role in concurrent product design process. To represent the precedence relationships among design activities, a directed graph is used to describe the design process. And the interdependency relationship between activities is illustrated by a Design Structure Matrix which is the transpose of the accessibility matrix of the corresponding graph. Using the DSM, an algorithm of recognizing the coupled activities during the design process is presented. Moreover, an algorithm to figure out the order levels of activities during the design process is proposed. And both algorithms are illustrated with a die design example. 相似文献
995.
本文通过大量事例说明了方法论对完成大型工程项目的重要意义,总结了工程技术中方法论的一般原理,并以此为指导,提出了大型自动化系统开发中的新思路. 相似文献
996.
997.
To deal with the planarization problem widely used in many applications including routing very-large-scale integration (VLSI) circuits, this paper points out that only when its vertices are arranged in some specific order in a line can a planar graph be embedded on a line without any cross connections or cross edges. Energy function is proposed to meet the need of embedding a graph on a single line and route it correctly. A Hopfield network is designed according to the proposed energy function for such embedding and routing. The advantage of the proposed method is that it not only can detect if a graph is a planar one or not, but also can embed a planar graph or the maximal planar subgraph of a non-planar graph on a single line. In addition, simulated annealing is employed for helping the network to escape from local minima during the running of the Hopfield network. Experiments of the proposed method and its comparison with some existent conventional methods were performed and the results indicate that the proposed method is of great feasibility and effectiveness especially for the planarization problem of large graphs. 相似文献
998.
Ultra-thin membrane with nanoscale through hole has great potential in biomedical applications, where precise controllability of porosity, pore size and film thickness is urgently required. The present work proposed a cost-effective way to prepare the ultra-thin nanoporous film with a promising controllability. Monodispersed nanoparticle, rather than photoresist, is used as the sacrificial material for this new lift-off process. By releasing the particles, holes can be achieved with predeter-mined characters. A 110 nm-thick nanoporous aluminum film with well-controlled pore's diameter was successfully fabricated to validate the technique. The technique has wider process window and better applicability than other nanofabrication methods. 相似文献
999.
QST108为意法半导体公司生产的电容触摸传感器,具有功能强大且易操作等特点,非常适合应用在能够对用户触摸做出响应的智能控制界面中。本文重点介绍了QST108的工作方式及主要操作命令,给出了QST108与PIC单片机的接口设计以及部分程序代码。 相似文献
1000.
80C51原始IP核内部RAM的扩展方案 总被引:2,自引:0,他引:2
80C51系列单片机是一类经典的8位微处理器,其设计方法和体系结构一直是其他各类单片机设计的参考典范,自从20世纪80年代面世以后,得到了极大的发展与应用。直到今天,市场上还有一大部分单片机应用成品将其作为处理核心。基于80C51系列单片机无知识产权保护、市场应用广泛等优点,对其进行功能拓展,既有利于经济上节约成本,也有利于成果的推广使用。 相似文献