设有关系模式只(C,P,S,G,T,W),各属性含义为:C课程,P老师,S学生,G成绩,T时间,W教室,其函数依赖集为:F=C→P,(S,C)→G,(T,W)→C,(T,P)→W,(T,S)→W则关系模式的关键字为 (35) ,R的规范化程度最高可达到 (36) 。若将R分解为关系模式组R1 (C,P),R2(S,C,G),R3(S,T,W,C),则R1,R2,R3的规范化程度最高分别可达到 (37) , (38) , (39) 。 (38)处填()。
A. 2NF
B. 3NF
C. BCNF
D. 4NF
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The grid computing is a new (66) technology connecting the distributed and (67) resources to the high-speed network and integrating a super-computer of processing capacity. The significance and architecture of the grid computing is explained. Several kernel technology such as OGSI, resource management, task management, task scheduling, high rate communication and security are described. Aiming at the particularity of the grid computing environment a mechanism similar to the technology of the search engine is designed to registry, discovery and (68) the resources in the grid. The whole model of the resource management is built by connecting task manager in the local resource management system to others with P2P model. The task may migrate among the task managers in order to (69) the load. The task users summit may be executed in relatively tight resource set, which will not only decrease the total communication overheads of the whole task but also (70) the performance of the system. (70)处填()。
A. decrease
B. enhance
C. keep
D. balance
物业管理绿化的基本要求有( )。
A. 保持植物正常生长
B. 保持环境生态系统良性循环的效果
C. 及时对妨碍业主、物业使用人活动的绿化植株进行改造,减少人为践踏对绿化造成的危害
D. 经常进行绿化改造,满足部分业主的特殊爱好
E. 加强枯枝黄叶的清理及绿化保洁工作
设有关系模式只(C,P,S,G,T,W),各属性含义为:C课程,P老师,S学生,G成绩,T时间,W教室,其函数依赖集为:F=C→P,(S,C)→G,(T,W)→C,(T,P)→W,(T,S)→W则关系模式的关键字为 (35) ,R的规范化程度最高可达到 (36) 。若将R分解为关系模式组R1 (C,P),R2(S,C,G),R3(S,T,W,C),则R1,R2,R3的规范化程度最高分别可达到 (37) , (38) , (39) 。 (36)处填()。
A. 2NF
B. 3NF
C. BCNF
D. 4NF
设有关系模式只(C,P,S,G,T,W),各属性含义为:C课程,P老师,S学生,G成绩,T时间,W教室,其函数依赖集为:F=C→P,(S,C)→G,(T,W)→C,(T,P)→W,(T,S)→W则关系模式的关键字为 (35) ,R的规范化程度最高可达到 (36) 。若将R分解为关系模式组R1 (C,P),R2(S,C,G),R3(S,T,W,C),则R1,R2,R3的规范化程度最高分别可达到 (37) , (38) , (39) 。 (35)处填()。
A. (T,R)
B. (J,C)
C. (T,W)
D. (T,S)