Ning Fu Shigetoshi Nakatake Yasuhiro Takashima Yoji Kajitani Abstraction and optimization of consistent floorplanning with pillar block constraints. 19-24 2004 conf/aspdac/2004 ASP-DAC http://doi.acm.org/10.1145/1015090.1015098 db/conf/aspdac/aspdac2004.html#FuNTK04