public void add(ThreadUnitWork work)
 {
     lock (workLockObject)
     {
         this.works.Add(work);
     }
 }
 public void Remove(string id)
 {
     lock (workLockObject){
         ThreadUnitWork _work = this.works.Where(c => c.Id == id) as ThreadUnitWork;
         _work.Stop();
         this.works.Remove(_work);
     }
 }