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A New Method for the Detections of multiple faults Using Binary Decision Diagrams

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1943-1946页

作者： PAN Zhongliang CHEN Ling ZHANG Guangzhao School of Physics and Telecommunications Engineering South China Normal University Guangzhou 510631 Guangdong China Department of Electronics Sun Yat-sen University Guangzhou 510275 Guangdong China

With the complexity of integrated circuits is continually increasing, a local defect in circuits may cause multiple faults. The behavior of a digital circuit with a multiple fault may significantly differ from that of a single fault. A new method for the detection of multiple faults in digital circuits is presented in this paper, the method is based on binary decision diagram （BDD）. First of all, the BDDs for the normal circuit and faulty circuit are built respectively. Secondly, a test BDD is obtained by the XOR operation of the BDDs corresponds to normal circuit and faulty circuit. In the test BDD, each input assignment that leads to the leaf node labeled 1 is a test vector of multiple faults. Therefore, the test set of multiple faults is generated by searching for the type of input assignments in the test BDD. Experimental results on some digital circuits show the feasibility of the approach presented in this paper.

关键词： digital circuits multiple faults fault detection binary decision diagrams

Performance Analysis of Two RAIM Methods for multiple faults

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Performance Analysis of Two RAIM Methods for Multiple Faults

Robust Adaptive Diagnosis for multiple faults of Aeroengine Actuator

第三届中国卫星导航学术年会

作者： TONG Haibo, ZHAN Jianwei, ZHANG Guozhu, Ou Gang Satellite Navigation R&D Center, School of Electronic Science and Engineering, National University of Defense Technology Changsha, Hunan Province, China, 410073

As the development of Global Navigation Satellite System （GNSS）, fu- ture GNSS will be characterized with the diversity of constellations and frequen- cies. The performance integrity will be more concerned. Although the convention- al Receiver Autonomous Integrity Monitoring （RAIM） can provide one fault detection and exclusion. Two or more faults are still difficult to handle. Recently, various multi-fault RAIM methods are proposed. To evaluate the new method in the general way, an assessment model is presented and two typical methods are simulated in the model. The simulation results show that both the methods are ef- fective in LPV-200 when GPS and Galileo are fully operating. The improvement of VPL and the degraded position accuracy are analyzed quantitively. The pro- posed model provides a platform for the test and verification of the new multi- fault RAIM methods under development.

关键词： GNSS RAIM multiple faults vertical protection level assessment model

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Robust Adaptive Diagnosis for Multiple Faults of Aeroengine ...

multiple fault diagnosis of down-hole conditions of sucker-rod pumping wells based on Freeman chain code and DCA

第40届中国控制会议

作者： Jiang Yang Linfeng Gou Huihui Li Northwestern Polytechnical University School of Power and Energy

To solve the problems of low accuracy and poor robustness of the existing aeroengine multi fault diagnosis *** this paper,the actuator fault with high fault probability in aeroengine control system is taken as the research *** the parameter uncertainty and the existence of multiple multiplicative faults,the state space equation of the engine is established,and the adaptive robust diagnosis method is *** adaptive sliding mode observer is designed to detect the fault,and the adaptive observer is designed to estimate the multiplicative fault,System status tracking is *** results show that the proposed method is robust and adaptive while ensuring the accuracy of fault diagnosis and estimation.

关键词： Aeroengine multiple faults Fault diagnosis Fault estimation Adaptive SMO

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Petroleum Science 2013年第3期10卷 347-360页

作者： LI Kun GAO Xian-wen YANG Wei-bing DAI Ying-long TIAN Zhong-da College of Information Science and Engineering Northeastern University

It is important to achieve continuous, stable and efficient pumping well operation in actual oilfield operation. Down-hole pumping well working conditions can be monitored in real-time and a reasonable production scheme can be designed when computer diagnosis is used. However, it is difficult to make a comprehensive analysis to supply efficient technical guidance for operation of the pumping well with multiple faults of down-hole conditions, which cannot be effectively dealt with by the common methods. To solve this problem, a method based on designated component analysis （DCA） is used in this paper. Freeman chain code is used to represent the down-hole dynamometer card whose important characteristics are extracted to construct a designated mode set. A control chart is used as a basis for fault detection. The upper and lower control lines on the control chart are determined from standard samples in normal working conditions. In an incompletely orthogonal mode, the designated mode set could be divided into some subsets in which the modes are completely orthogonal. The observed data is projected into each designated mode to realize fault detection according to the upper and lower control lines. The examples show that the proposed method can effectively diagnose multiple faults of down-hole conditions.

关键词： Sucker-rod pumping wells multiple faults designated component analysis control chart Freeman chain code dynamometer card

FAULT DETECTION FOR multiple-VALUED LOGIC CIRCUITS WITH FANOUT-FREE

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Journal of Electronics(China) 2004年第5期21卷 376-383页

作者： PanZhongliang DeptofPhysics SouthChinaNormalUniversityGuangzhou510631

The single fault and multiple fault detections for multiple-valued logic circuits are studied in this paper. Firstly, it is shown that the cardinality of optimal single fault test set for fanout-free m-valued circuits with n primary inputs is not more than n + 1, for linear tree circuits is two, and for multiplication modulo circuits is two if n is an odd number or if n is an even number and m ＞ 3, where the optimal test set of a circuit has minimal number of test vectors. Secondly,it is indicated that the cardinality of optimal multiple fault test set for linear tree circuits with n primary inputs is 1 + [n/(m - 1)], for multiplication modulo circuits is n+ 1, for fanout-free circuits that consist of 2-input linear tree circuits and 2-input multiplication modulo circuits is not greater than n+ 1, where [x] denotes the smallest integer greater than or equal to x. Finally,the single fault location approaches of linear tree circuits and multiplication modulo circuits are presented, and all faults in the two types of circuits can be located by using a test set with n + 1 vectors.

关键词： multiple-valued logic Digital circuits Fault detection Single fault multiple faults