CPM/PERT
PERT is preferred over CPM as it reflects realistic scenario.
Earliest expected occurance time
- Time which event expected to occur earliest.
- When all activities leading to it are completed.
Latest allowable occurence time
- Time by which event must occur to keep project as schedule.
- Denoted by TL.
EOT
- forward pass
- merger point crucial
LOT
- backward pass
- burst point crucial
Stack: difference between LOT & EOT
- Positive slack : ahead of schedule
- Zero slack : on schedule
- Negative slack : behind schedule
Activity times:
- Earliest start time : earliest possible time at which event can be started.
- Earliest finish time : earliest time by which activity can be completed.
- Latest start time : latest time by which activity should be started without delaying the project.
- Latest finish time: latest time by which activity be completed.
- Path along which no activity has float.
- It represent path of longest duration in a network.
- It is shortest time taken to complete project.
In PERT , when there are more than one path with same expected duration , path with more uncertainity is considered critical path.
Floats:
Total float:
- Maximum delay possible without delaying project.
- Maximum available time - actual time required
- Takes away chance of delay from succeeding event.
Free float:
- Delay possible without affecting start of subsequent activity at its EST.
- Excess time available such that its successor also starts as early as possible.
Independent float:
- Delay possible such that it doesn't affect float of preceding as well as succeding activities.
Interference float:
- Difference of total float and free float.
Line balancing:
- To increase capacity of utilisation.
- Optimal utilisation of labour hours.
Production rate : determined by slowest station
Cycle time: established by bottleneck station.
Balance delay : measures line inefficiency.
- It is reducing project duration .
- Done along critical path.
- Done for activity of least cost slope.
- Cost slope = (crash cost - normal cost)/(normal time - crash time)
Cost funnel / progressive elaboration
- As project becomes more elaborate and detailed it has more accurate estimates.
- It is also called as rolling wave planning.
Risk
- Uncertain event
- Impact is positive for opportunity and negative for threat
- Probability and outcome both are known.
Risk register :it contains list of all identified risk and potential actions to be taken if they occur.
- Contains risk category ,risk description, risk impact , risk probability , risk severity, risk ownership, contingency plan.
- Risk score = probability x impact
Sensitivity analysis
- Changes are risk variable at a time.
- Output is TORANADD DIAGRAM which gives relative importance of variables
- If emv is positive then its for opportunity and negative for threat .
- Graphical method of selecting the best course.
- Interconnects event chronologically.
- Used Monte Carlo technique.
- Probability distribution is randomly assigned and may also use various input probability distribution.
Risk response : depending on threat or opportunity.
- Monitor : observe ,collect, record and report.
- Control : using data collected to bring actual program performance to planned performance.
- Helps identify project growth , project slippage and other problems.
Target S curve : reflect revised ambitions at an instant. 
Cost overrun : project spend more than its planned budget.
Cost under run: project is spending less than its planned budget.
Earned value analysis
Planned value or budgeted cost of work schedule
- Work schedule to be completed and value corresponding to it.
- Amount of work actually completed and value corresponding to it.
- Money actually spent in earning the earned value of money.
Note : EV always first , >1 is beneficial
CR = CPI x SPI
<1:Things are worse than planned
=1:things are as per plan
>1:things better than plan
In future : project completion after observation point .
- Estimate to completion
- Estimate at completion
- Budget at completion
- Variance at completion
EAC - new production for project based on performance and risk.
- VAC : value by project cost overruns or underarms
- Estimated CPI = (BAC/EAC)
- To complete CPI = (BAC-EV/BAC-AC) (when project is under budgeted).
- Resources must be utilised optimally to achieve highest productivity and avoid any under utilisation or over utilisation.
Resource levelling :
- Resources unlimited
- Duration constrained
- Resources limited
- Duration can be changed
- When changes are made in aspect of project.
- Frequent for short projects.
- Also when project approaches end of project.
- Activities are neither added nor deleted in it.
- Two popular techniques are fast tracking and crashing.
- Crashing : reduce project duration by increasing resources on activity.
- Fast-tracking : refers to carrying out activities concurrently.
Inventory : has idle resources which have economic value.
Types of system :
Classification :criteria ----- ABC analysis :usage value , XYZ analysis :investment / variability , HML analysis :unit price ,VED analysis: criticality of item , SDE analysis :procurement difficulty, GOLF analysis : source of requirement ,SOS analysis: seasonality ,FSN analysis : issues from store.
EOQ model
- Its quantity of material that minimise total annual cost for material in fixed order quantity inventory system.
- Demand constant
- Lead time constant
- Unit price constant
- Ordering cost per order constant
- Inventory carrying cost based on average inventory
- Where actual work occurs.
- Manage expectation of stakeholders while protecting the scope.
- Contract closure
- Lesson learnt documentation --- will form organisational process assets.
- Unbiased evaluation of work performed.
- Build up information base.
- Establish performance.
- Understand about problems.
- First phase : immediately after closing project
- Second phase: 2 to 3 years after closing.
Second phase : verify performance of projects deliverable.
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