1. National Pilot School of Software, Yunnan University , Kunming, P. R. China
2. School of Transportation Science and Engineering, Beihang University , Beijing, P. R. China
3. Beijing Engineering Center for Clean Energy and High Efficient Power, Beihang University , Beijing, P. R. China
4. Laboratoire international associé, Beihang University , Beijing, P. R. China
5. Department of Mathematics, Beijing Jiaotong University , Beijing, P. R. China
6. CRIStAL, UMR CNRS 9189, Centrale Lille , Villeneuve d'Ascq, Lille, France