1. School of Mechanical and Aerospace Engineering; Nanyang Technological University; Singapore 639798 Singapore
2. School of Materials Science and Engineering; Nanyang Technological University; 50 Nanyang Avenue Singapore 639798 Singapore
3. Micro-Nano Manufacturing and System Integration Center; Chongqing Institute of Green and Intelligent Technology; Chinese Academy of Sciences; Chongqing 400714 P. R. China
4. Key Laboratory for Thin Film and Microfabrication Technology of Ministry of Education; Department of Instrument Science and Engineering; School of Electronic Information and Electrical Engineering; Shanghai Jiao Tong University; 800 Dongchuan Road Shanghai 200240 P. R. China
5. Shanghai Engineering Research Center for Intelligent Diagnosis and Treatment Instrument; 800 Dongchuan Road Shanghai 200240 P. R. China
6. Center for Environmental Sensing and Modeling (CENSAM); Singapore-MIT Alliance for Research and Technology (SMART) Centre; Singapore 117543 Singapore
7. Department of Architecture; Massachusetts Institute of Technology; Cambridge MA 02139 USA