题目
Problem
A precedence table for a project is given below.
| Activity | Immediately preceding activities |
|---|---|
| A | _ |
| B | _ |
| C | _ |
| D | _ |
| E | A |
| F | A, B, C |
| G | C |
| H | C |
| I | D, H |
| J | E |
| K | E |
| L | F, G, I |
| M | G, I |
(a) Draw the activity network described in the precedence table, using activity on arc and exactly four dummies.
(5)
Given that there is a unique critical path for the network and that K is a critical activity,
(b) state the critical path for the network.
(1)
Given instead that all the activities shown in the precedence table have the same duration and K is not necessarily critical,
(c) state all the possible critical paths for the network.
(2)
(Total 8 marks)
题目中文翻译
下表给出了一个项目的优先级表。
| 活动 | 紧前活动 |
|---|---|
| A | _ |
| B | _ |
| C | _ |
| D | _ |
| E | A |
| F | A, B, C |
| G | C |
| H | C |
| I | D, H |
| J | E |
| K | E |
| L | F, G, I |
| M | G, I |
(a) 使用弧表示活动并恰好使用四个虚活动，画出优先级表描述的活动网络。
已知该网络存在唯一关键路径且 K 是关键活动，
(b) 说明该网络的关键路径。
改为已知优先级表中所有活动的持续时间相同且 K 不一定是关键活动，
(c) 说明该网络所有可能的关键路径。