\\Diamond\Users\itot\ipsj-grcad-2001cg103.prn.pdf1 ( ) E-mail: itot@computer.org An Improvement of Force-directed Graph Layout Method Takayuki ITOH Keisuke INOUE Jun DOI Yasumasa KAJINAGA Yuko IKEHATA IBM Research, Tokyo Research Laboratory Graph data visualization is a very vital research topic because it is very useful for analysis and arrangement for various data such as financial, traffic, communication, social, scientific, computer system,
