**11. Acknowledgments**

The author would like to thank Prof. Tang Tongyi (Ph.D. supervisor of the author) of Tsinghua University for his guidance in the investigation of the algorithm, as well as Profs. Zhang Zhonghua and Zhang Deshi of the NIM and Prof. Yang Fusheng of Tsinghua University for their guidance. Appreciation also goes to Mr. Wang Lei of the NIM for his work in the construction of the equipment, as well as Ms. Li Min, Ms. Liu Lijuan, and Mr. Zhou Hao for their contributions to the project. Special thanks to Dr. Eddy So of the National Research Council of Canada for his valuable advice.
