Although lots of valuable results for fault diagnosis based on model have been achieved in linear system, it is difficult to apply these results to non-linear system due to the difficulty of modeling the non-linear sy...Although lots of valuable results for fault diagnosis based on model have been achieved in linear system, it is difficult to apply these results to non-linear system due to the difficulty of modeling the non-linear system by analysis. Adaptive Fuzzy system provides a way for solving this problem because it can approximate any non-linear system at any accuracy. The key for adaptive Fuzzy system to solve problem is its learning ability, so the authors present a learning algorithm for Adaptive fuzzy system, which can build the system's model by learning from the measurement data as well as experience knowledge with high accuracy. Furthermore, the experiment using the learning algorithm to model a servo-mechanism and to construct the fault diagnosis system based on the model is carried out, the results is very good.展开更多
A new theory- the fuzzy probability logic theory is presented , This theory incorpo- rates the genterally-used fuzzy logic and the traditionally-used probability logic theory in attempt to emulate the rational fault d...A new theory- the fuzzy probability logic theory is presented , This theory incorpo- rates the genterally-used fuzzy logic and the traditionally-used probability logic theory in attempt to emulate the rational fault diagnosis under uncertainty. According to the theory , an inference model , named as FSL , is thus designed to be devoted to the building of a fault diagnosis expert system for rotating machinery (ROSLES) . The system is put into operation on a vibration simula- tor stand for 300 MW turbine generator set ( 1 : 1 0) and satisfactory results are gained.展开更多
A sequential diagnosis method is proposed based on a fuzzy neural network realized by "the partially-linearized neural network (PNN)", by which the fault types of rotating machinery can be precisely and effectivel...A sequential diagnosis method is proposed based on a fuzzy neural network realized by "the partially-linearized neural network (PNN)", by which the fault types of rotating machinery can be precisely and effectively distinguished at an early stage on the basis of the possibilities of symptom parameters. The non-dimensional symptom parameters in time domain are defined for reflecting the features of time signals measured for the fault diagnosis of rotating machinery. The synthetic detection index is also proposed to evaluate the sensitivity of non-dimensional symptom parameters for detecting faults. The practical example of condition diagnosis for detecting and distinguishing fault states of a centrifugal pump system, such as cavitation, impeller eccentricity which often occur in a centrifugal pump system, are shown to verify the efficiency of the method proposed in this paper.展开更多
A computer aided consultant system for mammogram diagnosis is proposed in this paper based on mammogram segmentation as an image mining technique, to aid radiologistis in X ray film interpretation. The general a...A computer aided consultant system for mammogram diagnosis is proposed in this paper based on mammogram segmentation as an image mining technique, to aid radiologistis in X ray film interpretation. The general architecture of the system is introduced first, followed by a discussion of mammogram segmentation using logic filter, an analysis of the statistical data to the diagnostics with respect to different clinical information, and a brief introduction to a fuzzy decision making subsystem. Finally some experimental results are given.展开更多
This article has selected useful diagnostic parameters according to the running condition of PZ12V190B diesel, and built fuzzy vectors of this parameter by using the subjection function to establish a technological co...This article has selected useful diagnostic parameters according to the running condition of PZ12V190B diesel, and built fuzzy vectors of this parameter by using the subjection function to establish a technological condition. By using a statistical method the standard vector has been obtained, so the diesel technological level can be determined by calculating the closing degree between the fuzzy vector and the standard fuzzy vector.展开更多
文摘Although lots of valuable results for fault diagnosis based on model have been achieved in linear system, it is difficult to apply these results to non-linear system due to the difficulty of modeling the non-linear system by analysis. Adaptive Fuzzy system provides a way for solving this problem because it can approximate any non-linear system at any accuracy. The key for adaptive Fuzzy system to solve problem is its learning ability, so the authors present a learning algorithm for Adaptive fuzzy system, which can build the system's model by learning from the measurement data as well as experience knowledge with high accuracy. Furthermore, the experiment using the learning algorithm to model a servo-mechanism and to construct the fault diagnosis system based on the model is carried out, the results is very good.
文摘A new theory- the fuzzy probability logic theory is presented , This theory incorpo- rates the genterally-used fuzzy logic and the traditionally-used probability logic theory in attempt to emulate the rational fault diagnosis under uncertainty. According to the theory , an inference model , named as FSL , is thus designed to be devoted to the building of a fault diagnosis expert system for rotating machinery (ROSLES) . The system is put into operation on a vibration simula- tor stand for 300 MW turbine generator set ( 1 : 1 0) and satisfactory results are gained.
基金Sci-Tech Planning Projects of Chongqing City,China(No.CSTC2007AA7003).
文摘A sequential diagnosis method is proposed based on a fuzzy neural network realized by "the partially-linearized neural network (PNN)", by which the fault types of rotating machinery can be precisely and effectively distinguished at an early stage on the basis of the possibilities of symptom parameters. The non-dimensional symptom parameters in time domain are defined for reflecting the features of time signals measured for the fault diagnosis of rotating machinery. The synthetic detection index is also proposed to evaluate the sensitivity of non-dimensional symptom parameters for detecting faults. The practical example of condition diagnosis for detecting and distinguishing fault states of a centrifugal pump system, such as cavitation, impeller eccentricity which often occur in a centrifugal pump system, are shown to verify the efficiency of the method proposed in this paper.
文摘A computer aided consultant system for mammogram diagnosis is proposed in this paper based on mammogram segmentation as an image mining technique, to aid radiologistis in X ray film interpretation. The general architecture of the system is introduced first, followed by a discussion of mammogram segmentation using logic filter, an analysis of the statistical data to the diagnostics with respect to different clinical information, and a brief introduction to a fuzzy decision making subsystem. Finally some experimental results are given.
文摘This article has selected useful diagnostic parameters according to the running condition of PZ12V190B diesel, and built fuzzy vectors of this parameter by using the subjection function to establish a technological condition. By using a statistical method the standard vector has been obtained, so the diesel technological level can be determined by calculating the closing degree between the fuzzy vector and the standard fuzzy vector.