week 6

Question 1

What are the 3 planning horizons?

Answer 1

1. strategic planning
   long term planning; capacity planning
2. Tactical planning
   intermediate planning; aggregate planning and master requirement planning
3. Operational planning
   short term; short-term scheduling

Question 2

What is the bull-whip effect?

Answer 2

When one small disturbance downstream( sales), leads to major disturbances upstream (factory)
Smalll order changes may lead to large upstream order variations

Question 3

What is the lumpy-demand effect?

Answer 3

ROP system is not fit for unexpected high demands

Question 4

What is dependent demand?

Answer 4

When demand of an item is dependent on the demand of another product. The demand of a component of a product is dependent on the product.

Question 5

What is MRP based on?

Answer 5

It is based on dependent demand and focuses on raw materials and WIP

Question 6

What are the requirements for effective use of dependent demand?

Answer 6

1. Master production schedule (MPS)
2. Bills-of-material (BOM)
3. Inventory availability
4. Purchase orders outstanding

Question 7

What is the structure of the MRP system?

Answer 7

1. Requires a bill-of-material, lead times, inventory data, purchasing data, and the MPS

Question 8

What are bills of material?

Answer 8

BOM is the list of materials that is needed for the product

Question 9

What are parents and child in bom?

Answer 9

parent is the item consisting of components.
Child is the components of the product it is making

Question 10

What is low level coding?

Answer 10

Low level coding assigns the finished product or top product as level 0. The lower levels mean high level number. If some items occur at different levels, it is coded at the lowest level it occurs, meaning highest level number.

Question 11

What are the special BOM’s?

Answer 11

1. modular bills
   boms are made for modules, major subassemblies
2. Planning bills
   used to assign artificial parents (a kit). reduces number of items scheduled. this is like a box of screws and nails
3. phantom bills
   phantom bills are for assemblies that exist temporarily

Question 12

What is system nervousness

Answer 12

The frequent re-planning of production. Time fences means allowoing a segment of the master production schedule to be designated as not to be rescheduled

Question 13

Master production schedule or MPS?

Answer 13

The aggregate plan is disaggregated into individual end items.

Question 14

What are the time horizons of MPS?

Answer 14

1. Frozen period
   The schedule is frozen over an x amount of weeks.
2. Firm period
   products are confirmed by customers
3. full period
   full with plant products and cannot accept all orders
4. you can accept more orders

Question 15

What is available to promise?

Answer 15

The space between the forecast and firm orders. Forecast is replaced by orders

Question 16

where should MPS be put in Mto, AtO, MtS?

Answer 16

MPS should be put in beginning for mto, middle with modules for ato, and end for mts

Question 17

what is mrp II?

Answer 17

MRP II is called material resource planning when MRP I is already put in place. It contains feedback and uses overlapping, operations splitting, and lot splitting.

Question 18

What is RCCP?

Answer 18

rough cut capacity planning, which is done prior to MRP calculations. it checks for bottleneck capacities. If there are bottlenecks meaning the capacity is exceeded, the lots are moved around to fit it.

Question 19

What is CRP

Answer 19

capacity requirements planning

Question 20

What is a time bucket?

Answer 20

time bucket is the length of a period.

Question 21

What is Safety stock in MRP?

Answer 21

safety stock does not need to be considered when writing the actual MRP schedule. it is adjusted afterwards for using it when necessary

Question 22

What are exception messages and the types?

Answer 22

An exception message occurs when there is an error.
1. Reschedule out
means to reschedule the schedule receipts to a further period
2. reschedule in
means to reschedule the schedule reciepts closer
3. planned order past due
planned order does not arrive on due date as the lead time is longer

Question 23

What is the assumptions of the algorithm of Wagner Whitin

Answer 23

The algorithm has 3 assumptions:
1. demand during periods are known
2. stock at the end of last period is zero
3. setup/order cost are known

Question 24

what is the goal of wagner whitin

Answer 24

the goal is to find the optimal order quantity for each period.
So in the first period, do we only order for one period or do we order for 4 periods in that one order.
It is about trying to identify the best order options.

Question 25

What is the silver-meal approach?

Answer 25

The silver meal approach calculates the average cost per period. The goal is to calculate the average cost per period. once the average goes up again, that is when a new order should be placed

Question 26

What is the processes frequency calculation methods?

Answer 26

1. regeneration
   process all records of MRP in fixed time periods
2. net-change
   process records that were related to the incident when it occurs

Question 27

What is pegging

Answer 27

pegging is bottom-up planning. Pegging enables the planner to see products make use of which product.what

Question 28

what are the 2 types of pegging

Answer 28

1 single level pegging
looks only one level up in bom
2. full pegging
mrp looks for all orderes at all levels which will be affected by problems

Question 29

What is MPS or master production schedule?

Answer 29

MPS is a timetable that specifies what is to be made when. MPS is the schedule of main aspects.

Question 30

What is demand-driven MRP (DDMRP)?

Answer 30

DDMRP is strategically altering lead times and placing SS levels within bom structure to improve mrp performance. We want to decide how much and where to put SS in the bom

Question 31

What is capacity planning in MRP

Answer 31

load reports show the resource requirements in a work center