题目
A project is modelled by the activity network shown in Figure 2. The activities are represented by the arcs. The number in brackets on each arc gives the time, in days, to complete the activity. Each activity requires one worker. The project is to be completed in the shortest possible time.
[The sum of the durations of all the activities is 133 days]
(a) Complete the precedence table in the answer book.
(b) Complete Diagram 1 in the answer book to show the early event times and the late event times.
(c) State the critical activities.
(d) Calculate the total float for activity J. You must make the numbers you use in your calculation clear.
(e) Calculate a lower bound for the number of workers needed to complete the project in the minimum time. You must show your working.
Diagram 2 in the answer book shows a partly completed scheduling diagram for this project.
(f) Complete the scheduling diagram, using the minimum number of workers, so that the project is completed in the minimum time.
题目中文翻译
一个项目由图 2 所示的活动网络模拟。活动由弧表示。每条弧上的括号内的数字表示完成活动所需的时间（单位：天）。每项活动需要一名工人。项目应在最短时间内完成。
[所有活动持续时间之和为 133 天]
(a) 完成答案本中的优先级表。
(b) 在答案本中完成图 1，显示最早事件时间和最迟事件时间。
(c) 写出关键活动。
(d) 计算活动 J 的总时差。必须清楚说明计算中使用的数字。
(e) 计算在最短时间内完成项目所需的工人数量的下界。必须展示计算过程。
答案本中的图 2 显示了此项目部分完成的调度图。
(f) 使用最少数量的工人完成调度图，使项目在最短时间内完成。