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51.
Bingyong Yan Zuohua Tian Songjiao Shi 《International Journal of Electrical Power & Energy Systems》2008,30(5):343-360
In this paper, we propose a novel distributed robust fault detection and identification (RFDI) scheme for a class of nonlinear systems. Firstly, a detection and identification estimator—robust fault tracking approximator (RFTA) is designed for online health monitoring. A novel feature of the RFTA is that it can simultaneously detect and accurately identify the shape and magnitude of the fault and disturbance. Moreover, it takes less online training time compared with the traditional neural network based fault diagnosis schemes. For some distributed systems, a network of distributed estimators is constructed where the RFTA is embedded into each estimator. Then we use consensus filter to filter the outputs of each estimator. One of the most important merits of the consensus filter is that its outputs can dramatically improve the accuracy of fault detection and identification. Next, the stability of the distributed RFDI scheme is rigorously investigated. Finally, two numerical examples are given to illustrate the feasibility and effectiveness of the proposed approach. 相似文献
52.
Chia-Jung Pai Author Vitae Author Vitae Yu-Ming Liang Author Vitae Author Vitae Sei-Wang Chen Author Vitae 《Pattern recognition》2004,37(5):1025-1034
This paper presents a system that can perform pedestrian detection and tracking using vision-based techniques. A very important issue in the field of intelligent transportation system is to prevent pedestrians from being hit by vehicles. Recently, a great number of vision-based techniques have been proposed for this purpose. In this paper, we propose a vision-based method, which combines the use of a pedestrian model as well as the walking rhythm of pedestrians to detect and track walking pedestrians. Through integrating some spatial and temporal information grabbed by a vision system, we are able to develop a reliable system that can be used to prevent traffic accidents happened at crossroads. In addition, the proposed system can deal with the occlusion problem. Experimental results obtained by executing some real world cases have demonstrated that the proposed system is indeed superb. 相似文献
53.
The embedding of a small but expressive language of multidimensional functional programming in a well known and widely used language of object‐oriented programming leads to the combination of two radically different programming models. In this paper, we formally define the syntax and semantics of GLU?, which can be thought of as the multidimensional core of Lucid and GLU, and we describe its implementation as a language embedded in C++. With the aid of a few examples, we argue that the marriage of the two programming models is not only compatible and natural, but also that it produces a new and interesting hybrid language. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
54.
K.D. Do Author Vitae Z.P. Jiang Author Vitae Author Vitae H. Nijmeijer Author Vitae 《Automatica》2004,40(1):117-124
This paper presents a method to design an output-feedback controller that simultaneously solves global asymptotic stabilization and tracking of an underactuated omni-directional intelligent navigator—a spherical underwater vehicle moving in a horizontal plane (i.e. at a constant depth). The vehicle does not have a sway actuator and has only position and orientation measurements available. The control development is based on Lyapunov's direct method, backstepping technique and use of interconnected structure of the vehicle dynamics. Numerical simulations demonstrate the results. 相似文献
55.
P. Zhao J. C. Heinrich D. R. Poirier 《International journal for numerical methods in engineering》2004,61(6):928-948
A direct front‐tracking method using an Eulerian–Lagrangian formulation is developed in two space dimensions. The front‐tracking method is general in that it can track any type of interface once its local velocity is specified or has been determined by calculation. The method uses marker points to describe the interface position and tracks the interface evolution on a fixed finite‐element mesh, including growth, contraction, splitting and merging. Interfacial conditions are applied directly at the interface position. The method is applied to three scenarios that involve different interface conditions and are based on energy and mass diffusion. The three calculations are for the dendritic solidification of a pure substance, the cellular growth of an alloy, and the Ostwald ripening of silica particles in silicon. Numerical results show that very complicated interface morphologies and topological changes can be simulated properly and efficiently. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
56.
These experiments explored the role of prior experience in 12- to 18-month-old infants' tool-directed actions. In Experiment 1, infants' use of a familiar tool (spoon) to accomplish a novel task (turning on lights inside a box) was examined. Infants tended to grasp the spoon by its handle even when doing so made solving the task impossible (the bowl did not fit through the hole in the box, but the handle did) and even though the experimenter demonstrated a bowl-grasp. In contrast, infants used a novel tool flexibly and grasped both sides equally often. In Experiment 2, infants received training using the novel tool for a particular function; 3 groups of infants were trained to use the tool differently. Later, infants' performance was facilitated on tasks that required infants to grasp the part of the tool they were trained to grasp. The results suggest that (a) infants' prior experiences with tools are important to understanding subsequent tool use, and (b) rather than learning about tool function (e.g., hammering), infants learn about which part of the tool is meant to be held, at least early in their exposure to a novel tool. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
NetLinx技术的发展,使得跟踪系统发生了划时代的飞跃,在制造业上的应用更加广泛。本文以一间显像管厂为例,详细介绍了跟踪系统在制造业上的应用。 相似文献
58.
Qing Li 《Computer Standards & Interfaces》1991,13(1-3):99-103
The term ‘object-oriented database’ has been used to refer to different characteristics and mechanisms supported by semantic databases and (behaviorally) object-oriented ones. While this indicates the current confusion due to the lack of a common model, it also suggests the potential desirability of combining these two kinds of modeling facilities into the same nutshell. This paper summarizes from these two paradigms the features common to both, the features influenced/adopted by each other, and the features which are presented in one paradigm but missing from the other. After a brief analysis and discussion of these features, we conclude this paper by proposing our major theme: a complete object data model should take the union of the facilities offered by these two kinds of models. 相似文献
59.
60.
本文提出了一种直接把红外前视传感器的输出作为测量值来跟踪红外目标的扩展型卡尔曼滤波跟踪算法。在滤波处理时,设置可变的测量矩阵,其目的在于提高运算速度和抑制噪声干扰。通过具体的实例,对所提跟踪算法的特点和有效性进行了细致的分析。 相似文献