1. School of Mathematics, Hefei University of Technology 1 , Hefei, Anhui 230601, People’s Republic of China
2. Epic Systems Corporation 2 , 979 Milky Way, Verona, Wisconsin 53593, USA
3. Engineering Systems and Environment and Network Systems Science and Advanced Computing, University of Virginia 3 , P.O. Box 400298, Charlottesville, Virginia 22904, USA
4. Department of Physics, University of California, Irvine 4 , 4129H Frederick Reines Hall, Irvine, California 92697, USA
5. Department of Mathematics and Mathematical Biocomplexity Division, University of Virginia 5 , P.O. Box 400298, Charlottesville, Virginia 22904, USA