systemfile系统文件systemn.系统；体系；身体；制度System Independent Data Format独立的数据格式系统system of diophantine equation不定方程组system of dormitory management宿舍管理系统system of broadcasting network广播网方式system of condition monitoring振动在线监测系统system of appraisal indicators评估指标体系system hard-core diagnostics系统核心硬件诊断程序system of changed circumstance情势变更制度system of economic cooperation经济合作制度system of biological treatment生物处理系统