CAE 471_Lecture 2

Recording Policy: All participants are formally notified that the meeting is recorded for documentation and review purposes.
Interaction Tools: Instructions provided for utilizing the chat feature for queries and the virtual board for visual demonstrations.
Visibility Assurance: Participants are encouraged to report any technical lag or visibility issues immediately to ensure no instructional content is missed.

Project Network Diagrams: Visual representations of the sequence and interdependencies of project activities.
Collective Competence: Assessment of student confidence levels regarding homework assignments involving predecessor and successor relationships.

Finish to Start (FS): The most common relationship. The predecessor must be completed before the successor can begin. Logic: FinishA+Lag=StartBFinishA+Lag=StartB.
Start to Start (SS): The successor cannot start until the predecessor has started. This is often used for fast-tracking activities. Logic: StartA+Lag=StartBStartA+Lag=StartB.
Finish to Finish (FF): The successor cannot finish until the predecessor has finished. This ensures the delivery of the predecessor happens before the successor wraps up. Logic: FinishA+Lag=FinishBFinishA+Lag=FinishB.
Start to Finish (SF): A rare relationship where the start of the predecessor dictates the finish of the successor.

Standard activity nodes (often represented as rectangles in the Precedence Diagramming Method, PDM) contain specific data points:

Definition: The longest sequence of activities in a network diagram that determines the shortest possible project duration.
Identifying the Critical Path: It is characterized by activities where the Total Float equals zero (TF=0TF=0).
Risk Factor: Any delay in a critical path activity directly delays the project completion date. Projects may have multiple critical paths, which increases overall project risk profile.

Objective: To determine the Earliest Start (ES) and Earliest Finish (EF) Dates.
Rules:
- Initial activities begin at Day 0 (or Day 1, depending on convention).
- EF=ES+extDurationEF=ES+extDuration.
- If an activity has multiple predecessors, its ESES is the maximum EFEF of all preceding activities.

Objective: To determine the Latest Start (LS) and Latest Finish (LF) Dates without delaying the project finish date.
Rules:
- Start from the project end date (where LF=EFLF=EF of the final activity).
- LS=LF−extDurationLS=LF−extDuration.
- If an activity has multiple successors, its LFLF is the minimum LSLS of all succeeding activities.

Total Float (TF): The total amount of time an activity can be delayed from its early start without delaying the project finish date.
- Formula: TF=LS−ESTF=LS−ES or TF=LF−EFTF=LF−EF.
Free Float (FF): The amount of time an activity can be delayed without delaying the early start of its immediate successor.
- Formula: FF=ESextsuccessor−EFextpredecessorFF=ESextsuccessor−EFextpredecessor.

Lag: A directed delay inserted between activities. It is a required waiting period (e.g., waiting 3 days for concrete to cure before building on it).
Lead: Often referred to as negative lag; it allows an acceleration of the successor activity where it starts before the predecessor is fully finished.
Distinction from Float: Float is a byproduct of the network's mathematical logic (slack), whereas Lag is a deliberate, planned constraint added by the project manager.

Primavera P6 / MS Project: Discussion on how these tools calculate floats automatically but require manual input of logical relationships (FS, SS, etc.) and constraints.
Critical Path Shifts: In dynamic environments, the critical path can shift if non-critical activities exceed their float values, transforming them into critical activities.

Calculations Requirement: All submitted diagrams must show both Forward and Backward Pass values clearly.
Support: Students are encouraged to use university library resources for advanced CPM case studies and to contact tutors for software-specific troubleshooting.