1997年世界超声会议(WCU)于8月24～27日在日本横浜市召开。与会代表有来自日本、法国、德国、英国、美国、意大利等20个国家的近千名代表。会议讲演专题有:超声基础,超声换能器与材料,光声学和声光,超声测量,物理声学,超声器件,功率超声,超声马达,无损检测,声化学,医用超声,水下声学等。会议邀请了(德国)Gerhard-Mercator University的Joachim Herbert教授就"Safety of Medical Ultrasound"(日)东北大学的Kazuhiko Yamanouchi教授就"Future Trend of Acoustic wave Device",(美国)Yale University的Robert Apfel教授就"Super Oscillations of Drops and Surfactant Studies in Microgravity"作了特邀报告。会议期间设有超声设备/仪器展览。以下就物理声学、无损检测、水下声学专题略作介绍。
Explicit expressions of n Bcklund\|Darboux (BD) transformations and corresponding symmetries for generalized KdV (GKdV) equation, were constructed by using factorization of Gelfand\|Dickey operator. This extends Lous recent result about the BD transformations and non\|local symmetries for KdV, Kadomtsev\|Petviashvilli equations. As a by\|product, we also derive a representation of Wronskian determinant for the GKdV solution. PACC:
