To study the event importance and their role in the system fault evolution process (SFEP), and the possibility of fault mode, the analysis methods of event importance and possibility of fault mode are proposed. This paper is the series of research in related fields including four methods. The event importance in fault process to fault evolution is studied from fault mode. Change to Field theory is used to study the relationships between events in the fault process to judge the event importance. For the structure of space fault network (SFN), the possibility of fault mode is studied. Based on some events have occurred, the potential possibility of fault mode is studied. At the same time, some examples are given to illustrate the use and processes of these methods. These methods can study the event importance and the characteristics of fault occurrence in SFEP within the framework of SFN. The methods are suitable for computer information storage and data processing, and are suitable for intelligent analysis and data processing of SFEP, and enrich the theory of SFN

为了研究事件重要性及其在系统故障演化过程中的作用以及故障模式的可能性，提出了事件重要性和故障模式可能性的分析方法。本文是相关领域的一系列研究，包括四种方法。从故障模式研究了故障过程中事件对故障发展的重要性。变场理论用于研究故障过程中事件之间的关系，以判断事件的重要性。对于空间故障网络的结构，研究了故障模式的可能性。基于已发生的一些事件，研究了故障模式的潜在可能性。同时，给出了一些例子来说明这些方法的使用和过程。这些方法可以在SFN框架内研究SFEP中事件的重要性和故障发生的特征。该方法适用于计算机信息存储和数据处理，适用于SFEP的智能分析和数据处理，丰富了SFN的理论