Most of present workflow models lack formal definitions. So it is difficult to support the analysis on correctness and validity of process.
而且现有的工作流模型普遍缺乏严密的定义，很难支持对流程正确性、有效性的分析验证。
2
Validity of Participation: After receiving participation information, organizers will confirm the status of guests and send out formal invitation which will be used by guests to attend the meeting.
报名生效：收到报名信息后，组委会将进行来宾身份确认，并发出正式邀请函，凭邀请函入场。
3
In this paper, a singularly perturbed catalytic reaction problem is considered. The formal asymptotic solution is obtained and its uniform validity is proved.