4Department of Mathematics;
University of Maine;
Orono;
USA;
American Physical Society;
Maryland;
USA;
Department of Astronautics Engineering;
Harbin Institute of Technology;
Harbin;
China;
Department of Physics;
University of Maine;
Orono;
USA;
Nearest; Neighbor; Distance; Nearest; Neighbor; Vector; Anisotropy; SDSS; DR5; Galaxy; Distribution;