Ji Wu Kian-Lee Tan Yongluan Zhou QoS-Oriented Multi-query Scheduling over Data Streams. 215-229 2009 DASFAA http://dx.doi.org/10.1007/978-3-642-00887-0_17 conf/dasfaa/2009 db/conf/dasfaa/dasfaa2009.html#WuTZ09