restoring a log backup rolls forward the changes that were recorded in the transaction log to re-create the exact state of the database at the time the log backup operation started 如果丢失了日志备份,可能就无法将数据库还原到上次备份之后的某个时间点。microsoft建议您为一系列数据库备份存储一条日志备份链。
theoretically the varying contact rolling technology can increase the transverse stiffness of loaded roll gap, heighten the control effect of roll bending, improve the distribution of contact force between backup roll and work roll 从理论上分析了变接触轧制技术在提高承载辊缝横向刚度、增加弯辊力调控功效、改善辊间接触压力分布方面的作用。
parametric design makes interface between visual basic 6.0 and solidworks 2000 on the basis of program driving, and outputs three-dimensional parameterization model of work roll, backup roll, mill framework and finishing mill 参数化设计以程序驱动为基础,设计了visualbasic6.0和solidworks2000之间的接口,完成工作辊、支撑辊、机架和精轧机三维模型的输出。
a 2 dimensional varying thickness finite element model of roll system deformation was built to simulate and analyse rolling process, and then a vcr ( varying contact backup roll ) was designed for the rolling conditions of pl-tcm ( pickling line combined with tandem cold rolling mill ) and has been app-lied to 1700 tandem cold rolling mill at wisco after industrial test 采用二维变厚度有限元方法建立辊系弹性变形仿真模型,研制了酸轧联机条件下的vcr变接触支承辊,经过工业轧机现场轧制已成功投入1700冷连轧机实际应用。