Hidenao Abe Shusaku Tsumoto Detecting Temporal Patterns of Importance Indices about Technical Phrases. 252-258 2009 KES (2) http://dx.doi.org/10.1007/978-3-642-04592-9_32 conf/kes/2009-2 db/conf/kes/kes2009-2.html#AbeT09