The cone-shaped kernel distributions of vibration acceleration signals, whichwere acquired from the cylinder head in eight different states of a valve train, were calculatedand displayed in grey images. Probabilistic ...The cone-shaped kernel distributions of vibration acceleration signals, whichwere acquired from the cylinder head in eight different states of a valve train, were calculatedand displayed in grey images. Probabilistic Neural Networks ( PAW) was used to classify the imagesdirectly after the images were normalized. By this way, the problem of fault diagnosis for a valvetrain was transferred to the classification of time-frequency images. As there is no need to extractfeatures from time-frequency images before classification, the fault diagnosis process is highlysimplified. The experimental results show that the vibration signals can be classified accurately bythe proposed methods.展开更多
In view of the environmental and safety risks of hazardous chemical explosions in chemical enterprises,the fault tree analysis was used to establish a fault tree model of hazardous chemical explosions and comprehensiv...In view of the environmental and safety risks of hazardous chemical explosions in chemical enterprises,the fault tree analysis was used to establish a fault tree model of hazardous chemical explosions and comprehensively analyze the possibility of the explosions.The 34 basic events that caused hazardous chemical explosions were expounded,and the minimum cut and path sets were obtained.The structure importance of basic events were calculated.According to the minimum path sets,the basic events when the accident does not occur were determined,and combined with the sequence of structure importance,the preventive measures for hazardous chemical explosion accidents were proposed.The fault tree model intuitively clarified the correlation between the direct causes of hazardous chemical explosion accidents,and proposed directions for effectively reducing the probability of hazardous chemical explosion accidents in the chemical industry.展开更多
针对近几年气体绝缘金属封闭开关设备(gas insulated metal enclosed switchgear and controlgear,GIS)需求量增加,造成了组合电器质量下降,在运行中故障频发,暴露出GIS在变电站设计、设备选型、安装、投运、运行维护等方面存在安全隐...针对近几年气体绝缘金属封闭开关设备(gas insulated metal enclosed switchgear and controlgear,GIS)需求量增加,造成了组合电器质量下降,在运行中故障频发,暴露出GIS在变电站设计、设备选型、安装、投运、运行维护等方面存在安全隐患等问题。选取近年吉林省发生的典型GIS常见故障,对故障原因进行详细研究,归纳并分析了故障发生时的异同点,探究了其中的关键影响因素以及规律性原因,并且提出了相应的防范措施,提高了GIS安全运行的稳定性,减小故障对电气设备以及电力系统带来的负面影响。展开更多
文摘The cone-shaped kernel distributions of vibration acceleration signals, whichwere acquired from the cylinder head in eight different states of a valve train, were calculatedand displayed in grey images. Probabilistic Neural Networks ( PAW) was used to classify the imagesdirectly after the images were normalized. By this way, the problem of fault diagnosis for a valvetrain was transferred to the classification of time-frequency images. As there is no need to extractfeatures from time-frequency images before classification, the fault diagnosis process is highlysimplified. The experimental results show that the vibration signals can be classified accurately bythe proposed methods.
基金Supported by the Science and Technology Plan Project of Liaoning Province,China(2019JH8/10300102)。
文摘In view of the environmental and safety risks of hazardous chemical explosions in chemical enterprises,the fault tree analysis was used to establish a fault tree model of hazardous chemical explosions and comprehensively analyze the possibility of the explosions.The 34 basic events that caused hazardous chemical explosions were expounded,and the minimum cut and path sets were obtained.The structure importance of basic events were calculated.According to the minimum path sets,the basic events when the accident does not occur were determined,and combined with the sequence of structure importance,the preventive measures for hazardous chemical explosion accidents were proposed.The fault tree model intuitively clarified the correlation between the direct causes of hazardous chemical explosion accidents,and proposed directions for effectively reducing the probability of hazardous chemical explosion accidents in the chemical industry.
文摘针对近几年气体绝缘金属封闭开关设备(gas insulated metal enclosed switchgear and controlgear,GIS)需求量增加,造成了组合电器质量下降,在运行中故障频发,暴露出GIS在变电站设计、设备选型、安装、投运、运行维护等方面存在安全隐患等问题。选取近年吉林省发生的典型GIS常见故障,对故障原因进行详细研究,归纳并分析了故障发生时的异同点,探究了其中的关键影响因素以及规律性原因,并且提出了相应的防范措施,提高了GIS安全运行的稳定性,减小故障对电气设备以及电力系统带来的负面影响。
