[1] Univ Oulu, Optoelect & Measurement Tech, Oulu, Finland
[2] Chernivtsi Natl Univ, Opt & Publishing Dept, Chernovtsy, Ukraine
[3] Rivne State Med Ctr, Rivne, Ukraine
[4] Zhejiang Univ, Taizhou Res Inst, Coll Elect Engn, Hangzhou, Peoples R China
[5] Aston Univ, Coll Engn & Phys Sci, Birmingham, England