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依题意，对于关系代数表达式πR.A,S.B,S.C(σR.A＞S.B(R×S))，是先进行关系R和关系S的笛卡尔积运算，再选取关系R中属性A分量值大于关系S中属性B分量值的元组，最后再投影出关系R中属性A、关系S中属性B和属性C的相关元组。其运算结果集为三元关系。该关系代数表达式与元组演算表达式{t|(u)(v)(R(u)∧S(v)∧u[1]＞v[2]∧t[1]=u[1]∧t[2]=v[2]∧t[3]=v[3])}等价。
The IT service manager resigns from a project that meets the scheduleand budget. After hiring an alternativenew manager, the team is opposed to the comments from the new manager. The team is at （） developmentstages。
（）is closet to Deming's definition of Quality。
The IT service manager has learned that a software canimprove the efficiency of current and future project tasks. Because the software is fresh to the Company. Theengineer is not familiar with the software. The lT service manager decides to send the highest level engineero attend the external training course. The proiect manager uses （） risk strategies。
The process control charts are used （）。
Any one or any group of activities utilizing resources totransfer input into output can be viewed as a （）。
（ ）是在工业和信息化部、国家标准化管理委负会的联合指导下研制的，是我国IT服务行业最佳实践的总结和提升。
国家标准的制定有一套正常程序，分为预阶段、立项阶段、（ ）阶段、征求意见阶段、审查阶段、批准阶段、（ ）阶段、复审阶段及废止阶段。
