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61.
对基于IP网络的门禁控制系统整体设计方案及原理进行了简要的分析,提出了在系统框架上将B/S模式和C/S模式相结合的设计思想,同时通过引入通信模块,在管理软件和控制器之间架起了专用的TCP通道,给出了一种实现TCP/IP通信的新方法,并加入门禁控制器主动通信方式,测试证明该通信平台运行稳定,能够提高门禁控制系统的工作效率。 相似文献
62.
分析了现有的几种测试脚本生成技术,按照Mosley的同步数据驱动测试框架(CSDDT)框架设计并实现了一个针对面向对象程序的测试脚本生成器,通过实例验证了方法的可行性和工具的有效性,降低了产生测试脚本的工作量,对已知测试脚本产生过程中的弱点有很好的改进作用.生成脚本可以从单元测试开始应用,重用性良好,可同时测试多个类与方法,无须特定脚本开发语言. 相似文献
63.
64.
Changchun?Liu Michael?G.?Mauk Haim?H.?BauEmail author 《Microfluidics and nanofluidics》2011,11(2):209-220
An inexpensive, disposable, integrated, polymer-based cassette for loop-mediated isothermal amplification (LAMP) of target
nucleic acids was designed, fabricated, and tested. The LAMP chamber was equipped with single-use, thermally actuated valves
made with a composite consisting of a mixture of PDMS and expandable microspheres. The effect of the composite composition
on its expansion was investigated, and the valve’s performance was evaluated. In its closed state, the valve can hold pressures
as high as 200 kPa without any significant leakage. Both the LAMP chamber and the valves were actuated with thin film heaters.
The utility of the cassette was demonstrated by carrying out LAMP of Escherichia coli DNA target and reverse transcribed loop meditated isothermal amplification (RT-LAMP) of RNA targets. The amplicons were detected
in real time with a portable, compact detector. The system was capable of detecting as few as 10 target molecules per sample
in well under 1 h. The portable, integrated cassette system described here is particularly suited for applications at the
point of care and in resource-poor countries, where funds and trained personnel are in short supply. 相似文献
65.
66.
Changchun Hua Guopin Liu Zhenhua Bai Xinping Guan 《International journal of systems science》2016,47(16):3782-3791
In this paper, we focus on the problem of adaptive stabilisation for a class of interconnected uncertain switched stochastic nonlinear systems. Classical adaptive and backstepping technique are employed for control synthesis. Instead of estimating the switching parameters directly, we design the adaptive controller based on the estimations of bounds on switching time-varying parameters. A smooth function is introduced to deal with the difficulties caused by unknown interactions and tuning function approach is used to circumvent the overparameter problem. It is shown that under the action of the proposed controller all the signals of the overall closed-loop systems are globally uniformly bounded in probability under arbitrary switching. Simulation results are presented to illustrate the effectiveness of the proposed approach. 相似文献
67.
Xia Xu Changchun Hua Yinggan Tang Xinping Guan 《Neural computing & applications》2016,27(6):1451-1461
As a highly complex multi-input and multi-output system, blast furnace plays an important role in industrial development. Although much research has been done in the past few decades, there still exist many problems to be solved, such as the modeling problem. This paper adopts support vector regression (SVR) to construct the prediction model of blast furnace silicon content. To ensure a good generalization performance for the given datasets, it is important to select proper parameters for SVR. In view of this problem, a new particle swarm optimizer called DMS-PSO-CLS is presented to optimize the parameters of SVR. In DMS-PSO-CLS, a new cooperative learning strategy is hybridized with DMS-PSO, which makes particle information be used more effectively for generating better-quality solutions. DMS-PSO-CLS takes merits of the DMS-PSO and the cooperative learning strategy so that both the convergence speed and the convergence precision can be improved. Experimental results show that DMS-PSO-CLS can find the optimal parameters of SVR with high speed and the SVR model optimized by DMS-PSO-CLS can achieve a good regression precision on the predictive problem of blast furnace. 相似文献
68.
Distributed Adaptive Event‐Triggered Control for Leader‐Following Consensus of Multi‐Agent Systems
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This paper studies the leader‐following consensus problem for Lipschitz nonlinear multi‐agent systems using novel event‐triggered controllers. A distributed adaptive law is introduced for the event‐based control strategy design such that the proposed controllers are independent of system parameters and only use the relative states of neighboring agents, and hence are fully distributed. Due to the introduction of an event‐triggered control scheme, the controller of the agent is only triggered at it's own event times, and thus reduces the amount of communication between controller and actuator and lowers the frequency of controller updates in practice. Based on a quadratic Lyapunov function, the event condition which uses only neighbor information and local computation at trigger instants is established. Infinite triggers within a finite time are also verified to be impossible. The effectiveness of the theoretical results are illustrated through simulation examples. 相似文献
69.
MAO Wei ZHENG Fengtian MAO Jia School of Agricultural Economics Rural Development College of Transportation Renmin University of China Jilin University Beijing China Changchun Jilin Province China 《International Journal of Industrial Ergonomics》2006,(1)
I. INTRODUCTION Along with the economical rapid development and the living standard unceasing enhancement, the consumer request to food quality in a new stair, food consumption pattern has assumed multiplex development tendency, food demand pattern transforms into "the multi- varieties, guarantees safety". Food no longer only is essential item which satisfies life needs; the consumer attention to food from the quantity moves towards the credit level, food security problem appears. How doe… 相似文献
70.
本文心细介绍了基于无共享并行结构的并行嵌套环连接(PNLJ)算法的实现,旨在探索并行数据库系统的实现技术。 相似文献