I. What
Critical Path Method (CPM), also known as the path method, is an arithmetic method used in planning project activities. [1] for effective plan management, the Key Path is a very important tool. Similar to project evaluation and reviewtechniqu, pert. The estimated job time used by the method is single or definite, while the planned evaluation is the estimated job time with probability. These two technologies are often used together, or cpm/PERT for short.
II. Key Path, earliest occurrence time
Key Path:
The minimum time for project completion is the longest path length from the starting point to the ending vertex. The longest path from the starting vertex to the ending vertex is the Key Path.
You can directly observe the longest path from the start point to the end point in the AOV network. The longest path is the key path, and the longest path is the length of the Key Path.
Earliest occurrence time:
Ve (K) = max {ve (j) Dut (<j, k>)} (1.1)
J
Where T is the set of header vertices of all arcs whose ends are vertex VK (2 ≤ k ≤ n ).
Last occurrence time:
VL (j) = min {VL (k)-Dut (<j, k> )}
Kε s
S is the tail vertex set of all the arcs in the header (1 ≤ j ≤ N-1 ).
Latest occurrence time:
L (I) = VL (k)-Dut (<j, k>)
For example, there are two key paths: 10.
Summary:
1. ve (j) is pushed back and forth to find the maximum value;
2. VL (j) pushes forward from the back and finds the smallest value;
3. Likewise, the reasoning for E (I) and L (I) is also true;
Key Path Method