Important Ones Flashcards
What is the Difference between Planning and Scheduling?
Planning refers to establishing a set of tasks that need to be completed to achieve a desired goal
Scheduling refers to the timing of what needs to be completed
A plan may or may not have a “timing” associated with it, but scheduling is always about timing
What are the 4 fundamentals of General Supply Chain Matrix in order?
1) Procurement
2) Production
3) Distribution
4) Sales
What is the concept of rolling horizons?
Updating last planning runs on a certain frequence, whilst the actual month’s plan is held frozen
For example:
Frequency of planning: monthly
Planning horizon: 12 month plan, 1 month actual
What makes the optimization problem hard to solve? Especially the TSP?
Increasing problem size (due to variables and constraints) often means increasing number of feasible solutions.
The 3rd constraint of TSP the elimination of sub-tours is a such constraint. This makes it hard to solve!
What is a Master Plan?
What is a Master Plan used for?
A representation of the projects schedule, typically in a Gantt Chart format.
High-level schedule for the project, including major activities and key milestones.
3 Components of Master Project Planning & Scheduling?
1) Planning
2) Scheduling
3) Controlling
What are the 4 Criteria of the CPM? What do these criteria mean for the network?
- The Critical Path is the Longest Path through the Network
- The Critical Path is the Shortest Time in which the project can be completed
- Any delay in Critical Path Activities, delays the project
- Critical Path Activities have no Slack Time
CPM Algorithm?
1) Pass Forward Scheduling
• Begin at starting event and work forwards
• ES Rule:
> If an activity has only a single immediate predecessor, then its ES = EF of the predecessor
> If an activity has multiple immediate predecessors, then its ES = max of all the EF of its predecessors
• EF Rule:
> EF = ES + Activity Time
2) Backward Pass
• Begin with the last event and work backwards
• LF Rule:
> If an activity is an immediate predecessor for a single activity, then its LF = LS of the activity that immediately follows it
> If an activity is an immediate predecessor for multiple activities, then its LF = mn of all the LS of its predecessors
• LS Rule:
> LS = LF – Activity Time
3) Computing the Slack Time: Create the Table
• After computing the ES, EF, LS & LF for all activities, compute the Slack Time or Free Time for each activity
• Slack Time: Length of time an activity can be delayed without delaying the entire project
> Slack = LS – ES, or
> Slack = LF – EF
• Where the Slack = 0, is the Critical Path
4) Summarise the Results
• Expected Completion time is LF of last activity
• # of Activities are on Critical Path
• # of Activities are not on CP and have slack time
What are the goals of MTA?
- Early detection of schedule deviations
- Timely initiation of countermeasures
- Graphic representation of date trends showing comparison of milestones vs actual
- Overview of being able to meet deadlines or not
What Are Tech Push and Market Pull in New Product Development? Give examples
Technology PUSHES by latest science and technology advancements in society.
Night vision in s class (mainly because they could)
Market PULLS by needs of society and the market place. Electric car (demanded by customers)
What is OEE?
Overall Equipment Efficiency is a KPI to monitor and improve performance of production processes.
Availability * Performance * Quality = OEE
What Are OEE related losses?
All Time = Planned Production Time + Schedule Loss
Planned Production Time = Run Time + Availability Loss
Run Time = Net Run Time + Performance Loss
Net Run Time = Fully Productive Time + Quality Loss
What are the elements of Break-Even Computations ?
Q: Quantity (Volume of Production and Sales in Units) P: Price F: Fixed Costs V: Variable Costs TC = F + VQ TR = PQ TC = TR F + VQ = PQ => Q@BEP = F / (P – V) :For any Q larger than Q@BEP, the considered manufacturing scheme is feasible
What are the 4 Agency Problems?
1) Adverse Selection
2) Hold-Up
3) Moral Hazard Expertise
4) Moral Hazard Effort
Why do Complete Contracts not exist? Give 4 reasons!
I. Bounded Rationality: Limits in collecting information
II. Bounded Rationality: Difficulty in accurate forecasting
III. Measuring performance: Who? How?
IV. Asymmetric Information: Hidden Information / Hidden Action
How can unbalanced demand and supply can lead to vicious cycles?
Starts with “Make Vehicles to Forecast”, then 2 ways:
1) Push based selling using discounts and incentives
2) Reduced margins but attempt to reach EoS
3) More volume needed
And
1) Long lead times for custom-built vehicles
2) Build-to-order discouraged
3) Distorted demand information
Both end up back at “Make Vehicles to Forecast”
What are the 3 steps to Full Operations?
1) Production tests = TESTING
2) Ramp-Up = INCREASING CAPACITY
3) Operations = STEADY STATE CAPACITY
What is the MULTIPLE Heuristic Algorithm?
X: Number of non-fixed Departments with 1 to X referring to the sequence
T: # of iteration
1) Set:
a. MIN = cmin (cost of the current layout)
b. T = T+1
2) Exchange Departments I & J:
a. I = 1 to X-1
b. J = I+1 to X
3) Calculate & Set cij = cost of layout with the I & J exchanged
4) Is cij < cmin?
a. If YES, then Set cmin = cij and go to 5
b. If NO, then go to 5
5) Is this the LAST exchange for T?
a. If YES, then go to 6
b. If NO, then go to 2
6) Is AT LEAST ONE exchange IMPROVING the current layout cost?
a. If YES, then go to 7
b. If NO, Then END = NO FURTHER IMPROVEMENTS POSSIBLE FOR CURRENT LAYOUT
7) Layout cost MIN becomes current layout for next iteration, go to 1
What is the objective of the QAP in Layout Planning?
Minimise the total transportation costs
occurring due to the chosen layout
What is the objective function in QAP?
Min sumh=1sumi=1sumj=1sumk=1 thi * djk * xhj * xik
What are the 3 constraints of QAP?
1) sumj=1 xhj = 1 for h = 1,…,n : each OE h on exactly 1 location j
2) sumh=1 xhj = 1 for j = 1,…,n : each location j gets exactly 1 OE h
3) xhj = {0,1} : Binary Decision Variable
What are the components of Launch and Changeover, namely Product Creation Processes and Production Processes in order?
1) Prototyping
2) Pre-Series
3) Null-Series
4) Ramp-Up
5) Serial Production