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981.
982.
983.
阐述了无线传感器网络的组成及其主要特点,对其关键性问题进行了探讨。最后,介绍了无线传感器网络在军事和民用领域的应用情况。 相似文献
984.
Output feedback stabilization for time-delay nonlinear interconnected systems using neural networks. 总被引:1,自引:0,他引:1
In this paper, dynamic output feedback control problem is investigated for a class of nonlinear interconnected systems with time delays. Decentralized observer independent of the time delays is first designed. Then, we employ the bounds information of uncertain interconnections to construct the decentralized output feedback controller via backstepping design method. Based on Lyapunov stability theory, we show that the designed controller can render the closed-loop system asymptotically stable with the help of the changing supplying function idea. Furthermore, the corresponding decentralized control problem is considered under the case that the bounds of uncertain interconnections are not precisely known. By employing the neural network approximation theory, we construct the neural network output feedback controller with corresponding adaptive law. The resulting closed-loop system is stable in the sense of semiglobal boundedness. The observers and controllers constructed in this paper are independent of the time delays. Finally, simulations are done to verify the effectiveness of the theoretic results obtained. 相似文献
985.
986.
Wen Gao Bo Cao Shiguang Shan Xilin Chen Delong Zhou Xiaohua Zhang Debin Zhao 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2008,38(1):149-161
In this paper, we describe the acquisition and contents of a large-scale Chinese face database: the CAS-PEAL face database. The goals of creating the CAS-PEAL face database include the following: 1) providing the worldwide researchers of face recognition with different sources of variations, particularly pose, expression, accessories, and lighting (PEAL), and exhaustive ground-truth information in one uniform database; 2) advancing the state-of-the-art face recognition technologies aiming at practical applications by using off-the-shelf imaging equipment and by designing normal face variations in the database; and 3) providing a large-scale face database of Mongolian. Currently, the CAS-PEAL face database contains 99 594 images of 1040 individuals (595 males and 445 females). A total of nine cameras are mounted horizontally on an arc arm to simultaneously capture images across different poses. Each subject is asked to look straight ahead, up, and down to obtain 27 images in three shots. Five facial expressions, six accessories, and 15 lighting changes are also included in the database. A selected subset of the database (CAS-PEAL-R1, containing 30 863 images of the 1040 subjects) is available to other researchers now. We discuss the evaluation protocol based on the CAS-PEAL-R1 database and present the performance of four algorithms as a baseline to do the following: 1) elementarily assess the difficulty of the database for face recognition algorithms; 2) preference evaluation results for researchers using the database; and 3) identify the strengths and weaknesses of the commonly used algorithms. 相似文献
987.
Liu D Cao Y Kim KH Stanek S Doungratanaex-Chai B Lin K Tavanapong W Wong J Oh J de Groen PC 《Computer methods and programs in biomedicine》2007,88(2):152-163
Colonoscopy is an endoscopic technique that allows physicians to inspect the inside of the human colon. During a colonoscopic procedure, a tiny video camera at the tip of the endoscope generates a video signal of the internal mucosa of the colon. In current practice, the entire colonoscopic procedure is not routinely captured. Software tools providing easy access to important contents of videos that are digitally captured during colonoscopy are not available. Hence, it is very time consuming to review an entire video, locate important contents, annotate them, and extract the annotated contents for research, teaching, and training purposes. Arthemis, a software application, was developed to facilitate this process. For convenient data sharing, Arthemis allows annotation according to the European Gastrointestinal Society for Endoscopy (ESGE) Minimal Standard Terminology (MST), an internationally accepted standard for digestive endoscopy. Arthemis is part of our integrated capturing and content analysis system for colonoscopy called Endoscopic Multimedia Information System (EMIS). This paper presents Arthemis as a component of EMIS, the design and implementation of Arthemis, and key lessons learned from the development process. 相似文献
988.
利用近红外光谱法测定了烷烃分子的分子连接指数 ,并探讨了混合烃分子连接指数与单烃分子连接指数之间的关系。结果表明 :单烷烃分子连接指数具有可测性 ,而混合烃分子连接指数与单烃的分子连接指数之间存在线性加和的关系 相似文献
989.
针对带一类非线性参数系统的状态反馈自适应跟踪控制问题,通过设计一种新的李亚普诺夫函数--加权控制李亚普诺夫函数,由它作用于控制器和参数调整律,使之达到全局渐近跟踪从而满足控制指标。 相似文献
990.
基于微控制器的玻璃抗风压检测系统设计 总被引:1,自引:1,他引:0
本文介绍了用89C2051系列单片机设计的建筑玻璃抗风压检测系统。该系统能自动记录在不同风压作用下门窗受力构件测量点的位移量,其测量数据可直接读取,也可传送给上位机分析、处理、统计;上位机平台由VB语言设计完成。 相似文献