基于粗糙集和D-S证据理论的设备技术状态评估

针对设备技术状态评估中存在着不确定性,建立了基于粗糙集理论和D-S证据理论的设备技术状态评估模型,以提高评估的准确度,降低不确定性。首先利用粗糙集理论的知识约简功能来优化设备技术状态评估指标,其次采用D-S证据理论来组合优化过的指标,最后采用基于基本可信度分配的决策来获得设备的技术状态类别。以汽轮鼓风机为研究对象,详细描述了基于粗糙集理论和D-S证据理论的设备技术状态评估方法,并进行实例计算。实例表明采用粗糙集理论,优化了评估指标,减少了数据收集;采用D-S证据理论,进一步综合各指标,并能计算出评估结果可能存在的不确定性量。

Technical condition evaluation for devices based on rough set theory and D-S evidence theory

On the basis of uncertainty in technical condition evaluation of devices, a kind of technical condition evaluation method for devices based on rough set theory and Dempster-Shafter (D-S) evidence theory is presented to enhance the nicety and reduce the uncertainty. Firstly, indexes of the device are optimized by rough set theory; secondly, the indexes optimized are combined by D-S evidence theory; lastly, the technical condition of the device can be gained by the decision-making method based on the basic probability number. The method is applied to the Steamer-fan. The instance shows that the application of rough set theory optimized the indexes, so data collection is reduced. The application of D-S evidence theory integrates the indexes and computed the value of the uncertainty.