Nusmv状态和转换

Question

我想在NuSMv中表达这个问题：

• 用户可以处于以下三种状态之一：U-需要，U-使用，U-悲伤（代表需要服务的用户，开始使用，他/她对此质量感到满意服务或开始使用，而他/她分别由于服务质量低劣而感到难过。

• 服务可以处于以下三种状态之一：S-offer，S-good，S-bad； ;（代表未使用的服务，指提供优质服务的服务 或质量分别较差的服务。）

• 一组事件：外观，使用，停止，监视，检测-p，补救-p，表示寻找服务，开始使用服务，停止使用服务，监视质量，检测问题维修并分别解决问题。

• 这是我的SMV代码：

   MODULE main
   VAR
  
  
   Service: {S-offer,S-good,S-bad};
   User:{U-need,U-using,U-sad};
   Event:{look,use,stop,monitor,detect-p,remedy-p};
  
    ASSIGN
  
        init(Event) := look; 
        init(User) := U-need;
        init(Service) := {S-offer,S-good};
  
  
      next(Event) := case
  
      (Event = look) &  (Service=S-offer) : look;
      (Event = look) &  (Service=S-good) : use;
      (Event = use) &  (Service=S-good) : monitor;
      (Event = monitor) &  (Service=S-good) : {monitor,stop,detect-p};
      (Event = detect-p)  : remedy-p;
      (Event = remedy-p)  : monitor;
  
      TRUE:Event;
  
               esac;
  
  
      next(User) := case
  
      (Event = look) &  next(Event)=look : U-need;
      (Event = look) &  next(Event)=use : U-using;
      (Event = use) &  next(Event)=monitor : U-using;
      (Event = monitor) &  next(Event)=monitor : U-using;
      (Event = monitor) &  next(Event)=stop : U-need;
      (Event = monitor) &  next(Event)=detect-p : U-sad;
      (Event = detect-p ) &  next(Event)=remedy-p :  U-using; 
  
                  TRUE:User;
  
               esac;
        next(Service) := case
  
      (Event = look) &  next(Event)=look : S-offer;
      (Event = look) &  next(Event)=use : S-good;
      (Event = use) &  next(Event)=monitor : S-good;
      (Event = monitor) &  next(Event)=monitor : S-good;
      (Event = monitor) &  next(Event)=stop : S-offer;
      (Event = monitor) &  next(Event)=detect-p : S-bad;
      (Event = detect-p ) &  next(Event)=remedy-p :  S-good; 
  
                  TRUE:Service;
  
               esac;
  

-我想确认此代码代表我上面描述的问题 -我将事件和服务以及用户的状态都表示为变量，对吗？