MANUFACTURING LEARNING RESOURCES PLANNING INTRODUCTION Manufacturing resources planning (MRP II) involves various time-phased calculations such as master production scheduling (MPS), material requirement planning (MRP), lot sizing, and capacity requirement planning (CRP). These functions include many data item definitions and formulas. Since a data item affects data in other periods or in other tables, traditional statement of formula may not provide a clear concept for the learners. Spreadsheet such as Microsoft Excel enables students without computer programming background to establish a system of formulas and facilitates their understanding of related concepts. We discuss the application of spreadsheet to learning master production scheduling and material requirement planning. The related definitions and formulas are discussed and sample tables are established. An experiment was conducted: The spreadsheet tables are used in teaching a group of students and are compared with another group taught with tradi tional approach. Both groups are required to write a test. The result is analyzed by statistical tests. Previous research applied spreadsheets in determining kanban size [3] and production planning [2]. An example is described in section 2. Fundamental data including bill of material (BOM), item master, and inventory files are established in spreadsheets. In section 3, MPS and MRP are formulated with spreadsheets and related definitions and formulas are discussed. The advantages of teaching MPS and MRP with spreadsheet are discussed in section 4. Section 5 concludes our research. FUNDAMENTAL DATA OF AN EXAMPLE Suppose we have two finished goods A and B. Product A consists of component C and D, and product B of E and C, as shown in Figure 1. The BOM is shown in Table 1. The attributes in item master file related to MRP calculation include part number, lead-time, safety stock, safety time, and low-level-code (LLC). LLC used in sequencing the MRP calculation can be automatically determined from BOM. The item master is shown in Table 2.
A
B
C
D
E
C
E
FE
C
E
F
E
F
Figure 1: Product Structures
Table1:BillofMaterial Parent Comp QP LLC
1
A A D D C C B B
C D E C E F E C
2 1 2 1 1 1 1 1
2 1 3 2 3 3 3 2
Table1, 2 and 3 are all spreadsheet tables. Quantity-per in BOM, lead time, safety time and safety stock in item master, and all the quantities in inventory file are adjustable. Whatever data are adjusted, the related MPS and MRP tables are changed. All these adjustable data in Table1, 2 and 3 are arbitrary determined.
Table2:ItemMaster PartNo LT A 1 B 1 C 1 D 1 E 2 F 2
ST 0 0 0 0 0 1
SS 25 20 5 5 50 100
LLC 0 0 2 1 3 3
LSR FOQ/LFL FOQ/LFL FOQ/LFL FOQ/LFL POQ/LFL POQ/LFL
LS 1 1 500 200 3 2
SUC 5 5 10 10 10 10
CC 0.05 0.05 0.01 0.01 0.01 0.01
Notes: FOQ:FixedOrderQuanity LSR:LotSizeRule LFL:LotForLot LS:LotSize LT:LeadTime ST:SafeTimeexInspectionTime SS:SafeStock LLC:LowLevelCode Table3:Inventory ScheduledReceipts(OnOrder) PNo A B C D E F Notes: AL:AllocateLot ( ) OH:OnHand OH 20 40 60 60 100 100 AL 0 0 0 20 0 0 0 1 100 50 200 1500 1000 2 100 150 3 4 5 6 7 8 9 10
0
0
2
OO:OnOrder
MPS AND MRP Independent demand is the demand for a product not related to the demand for any other product. Dependent demand for a product occurs where its demand is derived from the demand of other items [1] [2] [5]. In our example, A and B are independent demand items, and the others are dependent demand items. Master production scheduling is a time-phased order point (TPOP) procedure for independent demand items. Material requirement planning is a similar procedure for dependent demand items. MRP procedure differs from TPOP in that the gross requirements in MRP come from explosion and those in TPOP come from independent sources [1]. Time-Phased Order Point A TPOP procedure involves gross requirement, schedule receipt, projected on hand, projected available balance, net requirement, planned order receipt, and planned order release. A TPOP table for product A is shown in Table 4. The gross requirement consists of customer orders and forecasts as shown in Table 5.
TimePhasedOrderPoint(TPOP): ; * Table4:TPOPforProductA Part:A Past OH= 20 Period Due 1 2 GR 0 80 50 SR 0 100 0 POH X 40 10 PAB X 40 25 NR X 0 35 PORcpt 0 35 POR 0 35 100 GRSRNRPORcptPOR POHPAB Notes: GR:GrossRequestment SR:ScheduledReceipts p POH:ProjectedOnHand; PAB:projectedAvailableBalance; PORcpt:PlannedOrderReceipts;* POR:PlannedOrderReleases; *
PastDue:
AL= 0 3 4 100 60 0 0 75 35 25 25 100 60 100 60 60 100
LT= 1 5 6 100 70 0 0 75 45 25 25 100 70 100 70 70 100
ST= 0 7 8 100 60 0 0 75 35 25 25 100 60 100 60 60 100
SS= 25 LFL 9 10 11 100 50 100 0 0 0 75 25 75 25 25 25 100 50 100 100 50 100 50 100 50
1 12 50 0 25 25 50 50 0
)
PNo A A B B
Type SO FCST SO FCST
0
1
80 100 70 50
Table5:IndependentDemand 2 3 4 5 6 7 50 100 60 80 70 60 50 100 50 100 50 100 100 50 90 60 110 60 100 50 100 50 100 50
8
60 50 50 100
9
40 100 40 50
10 30 50 20 100
11 20 100 0 50
3
Notes: SO:SalesOrder FCST:Forecast DTF:DmandTimeFence PTF:PlanningTimeFence
onIn an MPS, the major sources of gross requirement include customer orders and forecasts. The gross requirements consist of actual customer orders in periods between current date and the demand time fence (DTF), the larger of the customer order and forecast in periods between DTF and the planning time fence (PTF), and the forecast only beyond PTF. The formulas are: GR(t) = CO(t), for 0 t DTF; GR(t) = MAX(CO(t),FCS(t)), for DTF<t PTF; GR(t) = FCS(t), for PTF<t T. (1)
In the above equations, T is the planning horizon, GR(t), CO(t), and FCS(t) are gross requirement, customer order, and forecast in period t, respectively. Period 1 is the current period. The quantity appears in period 0 (past due) represents the accumulated uncompleted activities whose due dates already past. Therefore, CO(0) is a backorder, and SR(0) is a delayed scheduled receipt. The formulas for projected on-hands are: POH(1) = OH + max(SR(0),0) + SR(1) AL max(GR(0),0) - GR(1), for t=1; POH(t) = PAB(t-1) + SR(t) GR(t), for 2 t T. In the above equations, POH is the projected on-hand, and SR is the scheduled receipt.Net requirement occurs when POH(t) is smaller than the safety stock, SS. That is NR(t) = IF(POH(t) SS, 0, SS-POH(t)), for 1 t T. (3) (2)
If the lot-sizing rule is lot-for-lot (LFL), the planned order receipt (PORcpt) equals the net requirement, as shown in equation (4). PORcpt(t) = NR(t), for 1 t T. (4)
Planned order release (POR) is the planned order receipt after lead-time (LT) and safety-time (ST) offsetting. Safety-time makes the order be released earlier and keep the lead-time unchanged, i.e., the due date of the order is prior to the actual require date. All the past-due planned order releases are summed in POR(0). We assume the longest lead-time is 3 and the longest safety-time is 1. The formula is shown in equation (5). POR(0) = OFFSET(PORcpt(0),0,LT+ST) + OFFSET(PORcpt(0),0,MAX(LT+ST-1,0) + OFFSET(PORcpt(0),0,MAX(LT+ST-2,0) + OFFSET(PORcpt(0),0,MAX(LT+ST-3,0) POR(t) = OFFSET(PORcpt(t),0,LT+ST), for 1 t T. 4 (5)
POR(0) = OFFSET(PORcpt(0),0,LT+ST) + OFFSET(PORcpt(0),0,MAX(LT+ST-1,0) + OFFSET(PORcpt(0),0,MAX(LT+ST-2,0) + OFFSET(PORcpt(0),0,MAX(LT+ST-3,0) POR(t) = OFFSET(PORcpt(t),0,LT+ST), for 1 t T. (5)
Projected available balance is a projection of future inventory balance. It is the projected on-hand plus the planned order receipt, as shown in equation (6). PAB(t) = POH(t) + PORcpt(t), for 1 t T. (6)
Suppose we have three choices for lot sizing rules: lot-fot-lot (LFL), fixed-order-quantity (FOQ), and period-order-quantity (POQ). FOQ causes the planned orders to be generated for a predetermined quantity or its multiple, if the net requirement exceeds the predetermined quantity. Let Q be the fixed lot size, the formula is shown in equation (7). PORcpt(t) = IF(NR(t)>0, Q*(INT((NR(t)-1)/Q)+1),0), for 1 t T. (7)
Under POQ, the lot size is equal to the net requirements for a given number of periods. Let P be the fixed number of periods, the formula is shown in equation (8). PORcpt(t) = IF(NR(t)>0,IF(P>1,NR(t)+SUM(GR(t+1):OFFSET(GR(t+1),0, MAX(P-2,0))),NR(t),0), for 1 t T. (8)
From (7) and (8), we know that when Q=1, the lot-sizing rule FOQ turns into LFL, and when P=1, POQ turns into LFL. This is why the lot sizing rules are named to FOQ/LFL and POQ/LFL in the item master file. Master Production Schedule In MPS function, there are two important information -- MPS and available-to-promise (ATP). MPS and ATP are frequently used by production schedulers and sales people. MPS shows the scheduled and planned receipts of the end products. ATP tells the sales people how many can be promised to the customers in each period. Table 6 shows an MPS/ATP calculation for product A. A typical MPS report is shown in Table 7.
In the MPS/ATP report, customer order and forecast are for scheduler and sales peoples reference. Scheduled receipts are the released orders for the end products. Planned order releases are the quantities suggested by the system but have not yet been released by the scheduler. In this paper, we defined MPS as the sum of scheduled receipt and planned order receipt. That is MPS(t) = SR(t) + PORcpt(t), for 1 t T. (9)
ATP is the uncommitted portion of a companys inventory and planned production, maintained in the master schedule to support customer order promising. In Table 6, rows of mps period, accumulated customer order and insufficient are used to calculate ATP. ATP appears only in the first period and those periods with positive MPS. The related formulas are mps_period(t) = IF(MPS(t)=0, 0, 1). for 1 t T, acc_co(T) = CO(T),
5
(10) (11)
master schedule to support customer order promising. In Table 6, rows of mps period, accumulated customer order and insufficient are used to calculate ATP. ATP appears only in the first period and those periods with positive MPS. The related formulas are mps_period(t) = IF(MPS(t)=0, 0, 1). for 1 t T, acc_co(T) = CO(T), (10) (11)
acc_co(t) = CO(t)+acc_co(t+1)*ABS(mps_period(t+1)-1)+insufficient(t+1), for 2 t T, (12) acc_co(1) = CO(0)+CO(1)+acc_co(2)*ABS(mps_period(2)-1)+insufficient(2) insufficient(1) = IF(mps_period(1)=0, 0, max(acc_co(1)-MPS(0)-MPS(1)-OH,0)) insufficient(t) = IF(mps_period(t)=0, 0, max(acc_co(t)-MPS(t),0)), for 1 t T. ATP(1) = OH + MPS(0) + MPS(1) acc_co(1), ATP(t) = IF(mps_period=0, , IF(insufficient(t) 0, MPS(t)-acc_co(t),0)), (13) (14) (15) (16) for 2 t T. (17)
Table6:MPS/ATPCalculationforProductA Period 0 1 2 3 4 SO 0 80 50 100 60 FCST 0 100 50 100 50 MPS( 1) mpsperiod( 2) acc.SO.( 3) insufficient ATP X X X X 0 100 1 95 0 25 35 1 50 15 0 100 1 100 0 0 60 1 60 0 0
5
80 100 100 1 80 0 20
6
70 50 70 1 70 0 0
7
60 100 100 1 60 0 40
8
60 50 60 1 60 0 0
9
40 100 100 1 40 0 60
10 30 50 50 1 30 0 20
11 20 100 100 1 20 0 80
12
0 50 50 1 0 0 50
MPS+OHmpsperiod(LT)acc.SO ( )insufficient ( )ATP Notes: 1MPS=PORcpt+SR( + ) 2mpsperiod=LT 3 + (LT)insufficient+ (LT)acc.SO
Table7:AtypicalMPSReportforProductA Period 0 1 2 3 4 CO 0 80 50 100 60 SR 0 100 0 0 0 PORcpt 0 0 35 100 60 MPS 0 100 35 100 60 ATP X 20 15 0 0
5
80 0 100 100 20
6
70 0 70 70 0
7
60 0 100 100 40
8
60 0 60 60 0
9
40 0 100 100 60
10 30 0 50 50 20
11 20 0 100 100 80
12
0 0 50 50 50
From the customer order and forecast data in Table 5, we derive the TPOP table, MPS/ATP calculation, and MPS report for product B, as shown in Table 8, 9, and 10, respectively.
Table8:TPOPforProductB Part:B Past OH= 40 AL= 0 LT= 1 ST= 0 SS= 20 LFL 1
6
Period Due 1 2 3 4 GR 0 70 100 50 90 SR 0 50 100 0 0 POH X 20 20 30 70 PAB X 20 20 20 20 NR X 0 0 50 90 PORcpt 0 0 50 90 POR 0 0 50 90 60 Table9:MPS/ATPCalculationforProductB Period 0 1 2 3 4 CO 0 70 100 50 90 FCS 0 50 100 50 100 MPS X 50 100 50 90 mpsperiod X 1 1 1 1 acc.co. X 70 100 50 90 insufficient X 0 0 0 0 ATP X 20 0 0 0 Table10:AtypicalMPSReportforProductB Period 0 1 2 3 CO 0 70 100 50 SR 0 50 100 0 PORcpt 0 0 0 50 MPS 0 50 100 50 ATP X 20 0 0 MaterialRequirementPlanning
5
60 0 40 20 60 60 110
6 110 0 90 20 110 110 60 6 110 100 110 1 110 0 0
7
60 0 40 20 60 60 100
8 100 0 80 20 100 100 50 8
9
50 0 30 20 50 50 100
10 100 0 80 20 100 100 50 10 20 100 100 1 20 0 80
11 50 0 30 20 50 50 100 11
12 100 0 80 20 100 100 0 12
5
60 50 60 1 60 0 0
7
60 50 60 1 60 0 0
50 100 100 1 50 0 50
9
40 50 50 1 40 0 10
0 50 50 1 0 0 50
0 100 100 1 0 0 100
4
90 0 90 90 0
5
60 0 60 60 0
6 110 0 110 110 0
7
60 0 60 60 0
8
50 0 100 100 50
9
40 0 50 50 10
10 20 0 100 100 80
11
0 0 50 50 50
12
0 0 100 100 100
The gross requirements of the dependent items come from the planned order releases of their parent items. Please notice that they do not come from the MPS for items beneath the end products. The MRP procedure is similar to TPOP except that the gross requirement comes from planned order releases of other items. MRP procedure starts with the POR of master scheduled items. Low-levelcodes (LLC) in the item master file are used to determine the sequence of MRP calculation. The items with smaller LLC are calculated first. The planned order releases are obtained with a similar procedure as TPOP. Bills of material are used to explode the planned order releases of the parents to obtain the gross requirements of the components. The gross requirement of a component is the sum of all its parents planned order releases multiplied by the quantity-per in BOM. Since the LLC of the end product is zero, the highest level dependent items LLC must be one. MRP starts from the items with LLC one. The algorithm for MRP calculation is: PROCEDURE MRP; BOM explosion for POR(t) of MPS items and add to GR(t) of components; LLC 1; WHILE there exist any item not processed DO WHILE there exist any item with current LLC not processed DO PAB(0) OH-AL; {SR(0)>0 has been re-balanced} FOR t=1 TO T DO IF t=1 THEN POH(1) PAB(0)+SR(1)-GR(1)-max(GR(0), 0) ELSE POH(t) PAB(t-1)+SR(t)-GR(t); IF POH(t)<SS THEN NR(t) SS POH(t); PORCPT(t) Lotsizing(POH(t), NR(t), GR(t)); ELSE NR(t) 0; PORCPT(t) 0 ; 7 ENDIF;
IF t=1 THEN POH(1) PAB(0)+SR(1)-GR(1)-max(GR(0), 0) ELSE POH(t) PAB(t-1)+SR(t)-GR(t); IF POH(t)<SS THEN NR(t) SS POH(t); PORCPT(t) Lotsizing(POH(t), NR(t), GR(t)); ELSE NR(t) 0; PORCPT(t) 0 ; ENDIF; PAB(t) POH(t) PORCPT(t); + POR(t-LT) PORCPT(t); BOM explosion for POR(t-LT) and add to GR(t) of components; ENDFOR; Print MRP report for current item; ENDWHILE; LLC LLC+1; ENDWHILE; ENDPROCEDURE. In our example, the item with the smallest LLC is D (LLC=1). The MRP of D is calculated first as in Table 11, then C, E, F, as shown in Table 12, 13 and 14.
Low-level code 000
A
B
Table1:BillofMaterial Parent Comp QP LLC A C 2 2 D A 1 1 E D 2 3 C D 1 2 E C 1 3 F C 1 3 E B 1 3 B C 1 2
Low-level code 001
D
Low-level code 002
C
Low-level code 003
E
F
Low Level Code Structure
Table11:MRPReportforD Part:D Past OH= 60 Period Due 1 2 GR 0 35 100 SR 0 0 0 POH X 5 95 PAB X 5 105 NR X 0 100 PORcpt 0 200 POR 0 200 0 Table12:MRPReportforC Part:C Past OH= 60 Period Due 1 2 GR 0 270 250 AL= 20 3 4 60 100 0 0 45 55 45 145 0 60 0 200 200 0 LT= 1 5 70 0 75 75 0 0 200 ST= 0 7 8 60 100 0 0 115 15 115 15 0 0 0 0 0 200 SS= 5 FOQ 200 9 10 11 12 50 100 50 0 0 0 0 0 35 65 15 15 165 65 15 15 40 0 0 0 200 0 0 0 0 0 0 0
6 100 0 25 175 30 200 0
AL= 0 3 4 410 260
LT= 1 5 6 450 260
ST= 0 7 8 220 450
SS= 5 FOQ 500 9 10 11 12 200 250 200 0
8
SR POH PAB NR PORcpt POR
X X X
0
500
200 10 490 15 500 0
150 390 390 0 0 500
0 20 480 25 500 0
0 220 220 0 0 500
0 230 270 235 500 0
0 10 10 0 0 500
0 210 290 215 500 500
0 160 340 165 500 0
0 140 140 0 0 500
0 110 390 115 500 0
0 190 190 0 0 0
0 190 190 0 0 0
Table13:MRPReportforE Part:E Past OH= 100 AL= 0 Period Due 1 2 3 4 GR 500 400 550 490 560 SR 0 1500 0 0 0 POH X 700 150 340 560 PAB X 700 150 1120 560 NR X 0 0 390 0 PORcpt 0 0 1460 0 POR 0 1460 0 0 1610 Table14:MRPReportforF Part:F Past OH= 100 AL= 0 Period Due 1 2 3 GR 500 0 500 0 SR 0 1000 0 0 POH X 600 100 100 PAB X 600 100 100 NR X 0 0 0 PORcpt 0 0 0 POR 0 500 0 1000
LT= 2 5 510 0 50 50 0 0 0
6 560 0 510 1100 560 1610 0
ST= 0 7 8 600 450 0 0 500 50 500 50 0 0 0 0 750 0
SS= 50 POQ 3 9 10 11 12 600 50 100 0 0 0 0 0 550 150 50 50 200 150 50 50 600 0 0 0 750 0 0 0 0 0 0 0
4 500 0 400 100 500 500 0
LT= 2 5 0 0 100 100 0 0 0
6 500 0 400 600 500 1000 500
ST= 1 7 8 500 0 0 0 100 100 100 100 0 0 0 0 0 0
SS= 100 POQ 2 9 10 11 12 500 0 0 0 0 0 0 0 400 100 100 100 100 100 100 100 500 0 0 0 500 0 0 0 0 0 0 0
ADVANTAGES After three years of teaching manufacturing resources planning by using spreadsheets in Taipei and Toronto, we observed that the advantages include better understanding of the relationship between fundamental data files and MPS/MRP procedures, the MPS/MRP logic, the system design concepts, and the sensitivity analysis. The students in Taipei are from MIS department and have programming experiences and those in Toronto are MBA students without programming background, however, the advantages observed from their performance in assignments, tests, and term papers are identical.
Input Data of MPS/MRP The input data for MPS/MRP include customer order, forecast, on-hand inventory, scheduled receipt, allocation, lead-time, safety stock, safety time, parent-component relationship, etc. These input data are fed into MPS/MRP procedure from item master file, BOM file, inventory file, and open-order file. Spreadsheets such as Table 1, 2, 3, and 4 display the contents of the related files. Spreadsheet clearly presents the relationships of input data and MPS/MRP procedures. MPS/MRP Logic
9
The exploding, netting, and offsetting logic for MPS/MRP procedures are clearly defined by the
are fed into MPS/MRP procedure from item master file, BOM file, inventory file, and open-order file. Spreadsheets such as Table 1, 2, 3, and 4 display the contents of the related files. Spreadsheet clearly presents the relationships of input data and MPS/MRP procedures. MPS/MRP Logic The exploding, netting, and offsetting logic for MPS/MRP procedures are clearly defined by the formulas of the spreadsheet. Learners can understand the logic of MPS/MRP better by studying the formulas. System Design Concepts Learners without computer programming background can develop MPS/MRP systems with spreadsheets. By spreadsheet programming, their understanding of related subjects is ensured. Sensitivity Analysis Learners can understand the impacts of the change of input data to the MPS/MRP results by modifying the input data and observing the results immediately.
CONCLUSION MPS/MRP procedures along with the input data are standard operations planning approaches to most industries. Traditional ways of learning these topics are not effective for the related data and procedures are complicated. We define the data files and formulas in spreadsheets. Observing the results of teaching students of different backgrounds for three years, we found some advantages. The advantages include better understanding of the relationship between fundamental data files and MPS/MRP procedures, the MPS/MRP logic, the system design concepts, and the sensitivity analysis. Similar approach has also been applied to other areas such as capacity requirement planning, lot sizing rules, and distribution requirement planning.
REFERENCES 1. Apics, APICS Dictionary, Eighth Ed., Edited by J.F. Cox III, J.H. Blackstone Jr., and M.S. Spencer, American Production and Inventory Control Society, 1995. 2. Arnold, J.R.T., Introduction to Materials Management, Third Ed., Prentice-Hall, 1998. 3. Crandall, R.E., Production Planning in a Variable Demand Environment, Production and Inventory Management Journal, First Quarter, 1998. Pp. 34-41. 4. Hall, J.D., Bowden, R.O., Grant, R.S., and Hadley, W.H., An Optimizer for the Kanban Sizing Problem: A Spreadsheet Application for Whirlpool Corporation, Production and Inventory Management Journal, First Quarter, 1998. Pp. 17-22. 5. Plossl, G.W., Orlickys Material Requirement Planning, Second Ed., 1994.
10
5. Plossl, G.W., Orlickys Material Requirement Planning, Second Ed., 1994.
11
12
ScheduledReceipts(OnOrder) 11 12
13
12
0 50 0 100
14
15
16
5, we derive the TPOP table, MPS/ATP calculation, , 9, and 10, respectively.
17
18
19
20
21
22
RoughcutCapacity&CapacityRequirementPlanning
Endproduct A B BOM Parent A A B B D D C C Child C D C E C E E F 1 80 70 QtyPer 2 1 1 1 1 2 1 1 Opr 1/1 1/1 1/2 2/2 1/1 1/1 1/1 W/C 100 100 200 300 200 300 300 SetupTime 1.0 1.0 1.0 1.0 2.0 2.0 2.0 UnitSetupTime 0.025 0.050 0.025 0.025 0.033 0.020 0.020 UnitRunTime 0.025 1.250 0.575 0.175 0.067 0.080 0.0425 UnitTotalTime 0.05 1.30 0.60 0.20 0.10 0.10 0.0625 2 50 100 3 100 50 4 60 90 5 80 60 6 70 110 7 60 60 8 60 50 9 40 40 10 30 20 11 20 0 12 0 0 13 35 30 Total 685 680
RountingandStandardTimeData Endproduct LotSizes A 40 B 20 Components C 40 40 D 60 E 100 F 100
WithoutBOMandLeadTimeOffset OverallResourceCapacityRequiredbyOneUnitofEndProduct: Endproduct CapacityRequired/Unit
Low-level code 000
A
B
Low-level code 001 23
D
Low-level code 000
A B 1.91 2.26
A
B
BillofResourcesforEndProduct Workcenter A 0.05 1.30 0.56 1.91 B 1.30 0.60 0.36 2.26
Low-level code 001
D
100 200 300 Totaltime/Unit
Low-level code 002
C
Low-level code 003
E
F
11 12.37 17.41 8.48 38.26 12 0.00 0.00 0.00 0.00 13 43.59 61.36 29.87 134.82
PlannedCapacityRequirementsUsingOverallFactors W/C % 100 32.33 200 45.51 300 22.15 CapaRequired: 1 2 3 4 100.68 104.08 98.42 102.95 141.73 146.50 138.55 144.91 68.99 71.31 67.44 70.54 311.40 321.89 304.41 318.40
Low Level Code Structure
5 6 7 8 9 10 93.37 123.76 81.00 73.68 54.00 33.18 131.43 174.21 114.02 103.72 76.01 46.71 63.98 84.80 55.50 50.49 37.00 22.74 288.78 382.77 250.52 227.90 167.01 102.64
WithBOMbutwithoutLeadTimeOffset&YieldRate PlannedCapacityRequirementsUsingBillofResources WorkCenter 100 200 300 1 2 3 4 95.00 132.50 70.00 120.00 146.03 125.02 160.03 132.02 70.38 64.38 74.38 66.38 5 6 7 8 82.00 146.50 81.00 68.00 140.03 157.02 114.02 108.02 66.75 79.25 55.50 51.88 9 54.00 76.01 37.00 10 27.50 51.01 24.13 11 1.00 26.01 11.25 12 0.00 0.00 0.00 13 40.75 63.51 30.56
24
Total
311.40 321.89 304.41 318.40
288.78 382.77 250.52 227.90 167.01 102.64
38.26
0.00
134.82
WithBOMandLeadTimeOffsetbutwithoutYieldRate ProductLoadProfile 3 0.16 TimeOffset 2 1 1.20 0.40 0.06 0.10 0.80 0.10 Totaltime/Unit
EndproductA Workcenter100 Workcenter200 Workcenter300 EndproductB Workcenter100 Workcenter200 Workcenter300
0 0.05 1.30
0.05 1.30 0.56 1.30 0.80 0.16
1.91
2.26
PlannedCapacityRequirementsUsingProductLoadProfile(ProductA&B) W/C 100 200 300 Total Pastdue 0.00 220.03 49.50 269.53 1 2 3 4 95.00 132.50 70.00 120.00 205.02 122.03 174.02 140.03 62.88 47.63 56.13 50.63 362.89 302.16 300.15 310.65 5 6 7 8 9 82.00 146.50 81.00 68.00 54.00 167.02 126.02 94.02 72.01 43.01 48.50 39.63 28.38 20.50 10.00 297.52 312.15 203.40 160.51 107.01 10 27.50 2.01 5.69 35.19 11 1.00 42.00 15.88 58.88 12 0.00 27.51 3.00 30.51 13 40.75 0.00 0.00 40.75
Conflict
WithBOM&YieldRateandLeadTimeOffset PlannedCapacityRequirementsUsingConflictManagementMTO Endproduct 1 2 3 4 5 6 7 8 9 10 11 12 13 Total
25
A B MPSForEndproduct A B W/C 100 200 300 Total Pastdue 0.00 237.70 52.92 290.62
80 70 1 85 32
50 100 2 85 32
100 50 3 85 32
60 90 4 85 32
80 60 5 85 32
70 110 6 85 32
60 60 7 85 32
60 50 8 85 32
40 40 9 85 32
30 20 10 85 32
20 0 11 85 32
0 0 12 85 32
35 30 13 100 49 13 68.70 0.00 0.00 68.70
685 680 Total 1118 433
1 2 3 4 45.84 45.84 45.84 45.84 161.81 161.81 161.81 161.81 18.98 18.98 18.98 18.98 226.63 226.63 226.63 226.63
5 6 7 8 9 10 11 12 45.84 45.84 45.84 45.84 45.84 45.84 45.84 45.84 161.81 161.81 161.81 161.81 161.81 161.81 180.01 81.12 18.98 18.98 18.98 18.98 18.98 21.45 6.26 4.90 226.63 226.63 226.63 226.63 226.63 229.10 232.12 131.86
PlannedCapacityRequirementsUsingConflictManagementMTS MPSForEndproduct 1 2 3 4 5 A 65 65 65 65 65 B 65 65 65 65 65 W/C 100 200 300 Total Pastdue 0.00 214.52 47.13 261.65 1 2 3 4 87.75 87.75 87.75 87.75 161.23 161.23 161.23 161.23 47.13 47.13 47.13 47.13 296.10 296.10 296.10 296.10
6 65 65
7 65 65
8 65 65
9 65 65
10 65 65
11 65 65
12 65 65
13 65 65 13 87.75 0.00 0.00 87.75
Total 845 845
5 6 7 8 9 10 11 12 87.75 87.75 87.75 87.75 87.75 87.75 87.75 87.75 161.23 161.23 161.23 161.23 161.23 161.23 161.23 83.23 47.13 47.13 47.13 47.13 47.13 47.13 36.56 6.50 296.10 296.10 296.10 296.10 296.10 296.10 285.54 177.48
26
27
28
Conflict Managt.
29
30
ConflictManagement
CommonSense Sales=TotalCost TotalCost=MarginalCost+FixedCost What'sthepoints? BEP(S) BEP(Q) BEP(T) Parent A A D D C C B B Comp A B C D E C E F E C QP 1 1 2 1 2 1 1 1 1 1 LLC 0 0 2 1 3 2 3 3 3 2 FC/unit 17 5 5 7 0 5 0 0 0 5 acc.FC 17 5 10 7 0 5 0 0 0 5 MC/unit 8 3 2 4 1 2 1 1 1 2 BOM.MC 8 3 4 4 2 2 1 1 1 2 TotalCost/unit 25 8 ASP/unit 40 15
Note:TotalCoste V + Workcenter 100 200 300 Totaltime/unit TotalCost/unit ASP/unit YIELDRATE A 0.05 1.30 0.56 1.91 25 40 200 80% B 1.30 0.60 0.36 2.26 8 15 100 85% Limit168hr/Week
Capacity=1.91xQ(A)+2.26xQ(B) Sales=40xQ(A)+15xQ(B) TC(A)=200+25xQ TC(B)=100+8xQ
MaxProfit
31
TC(A)=200+25xQ TC(B)=100+8xQ
WithBOM&YieldRatebutwithoutLeadTimeOffset
Q 0 10 20 30 40 50 60 70 80 90 A TC(A) 200 513 825 1138 1450 1763 2075 2388 2700 3013 MFG.GP(A) 200.00 112.50 25.00 62.50 150.00 237.50 325.00 412.50 500.00 587.50 Capacity(A) 0 19 38 57 77 96 115 134 153 172 TC(B) 100 194 288 382 476 571 665 759 853 947 B MFG.GP(B) 100 44 12 68 124 179 235 291 347 403 Capcaity(B) 0 23 45 68 91 113 136 158 181 204 Total Capacity/Week 0 42 84 125 167 209 251 292 334 376 MPS(Q) 0 24 49 73 97 121 146 170 194 218
626
313.15
$ 600 500 400 300 200 100 0 100 200 300 0 10
CONCLUSION
MFG.GP(A)
MFG.GP(B)
1.BEP(Q) A:40Q(200+Q(25/(1(10.8))))=0 24.8 B:15Q(100+Q(8/(1(10.85))))=0 18.78 A&B:40Q(200+Q(25/(1(10.8))))=15Q(100+ Q(8/(1(10.85)))) Q=32 2.BEP(S) 24.8*40+18.78*15=$1,273.7
3.BEP(T)
Q 20 30 40 50
( A
24.8*1.91+18.78*2.26=89.8
60
80% B
70
80
A:60
32 x B 32 x A x * ( x 48 ) B:37 ( x 32 ) MaxProfit=240+71=311
85%) MPS
32
CONCLUSION : 6 32 h B 32 h A h * ( h 48 ) B:37 ( h 32 ) MaxProfit=240+71=311 ( A 80% B 85%) MPS A:60
WithBOM&YieldRateandLeadTimeOffset(Bottleneck)
Q 0 10 20 30 32 40 50 60 65 70 80 85 TC(A) 200 513 825 1138 1200 1450 1763 2075 2231 2388 2700 2856 A MFG.GP(A) Capacity(W200) 200.00 112.50 25.00 62.50 80.00 150.00 237.50 325.00 368.75 412.50 500.00 543.75 0 16 33 49 52 65 81 98 106 114 130 138 TC(B) 100 194 288 382 401 476 571 665 712 759 853 900
B MFG.GP(B) 100 44 12 68 79 124 179 235 263 291 347 375
Capcaity(W200) 0 9 19 28 30 38 47 56 61 66 75 80
Total Capacity/Week 0 26 51 77 82 103 128 154 167 180 205 218
MPS(Q) 0 24 49 73 78 97 121 146 158 170 194 206
MFG.GP(A)
MFG.GP(B)
1.BEP(Q) A:40Q(200+Q(25/(1(10.8))))=0 24.8 B:15Q(100+Q(8/(1(10.85))))=0 18.78 A&B:40Q(200+Q(25/(1(10.8))))=15Q(100+ Q(8/(1(10.85)))) Q=32 MTO MTS B= 32 A= 85 2.BEP(S) 24.8*40+18.78*15=$1,273.7 3.BEP(T) 24.8*1.91+18.78*2.26=89.8 A= 65 B= 65
600 400 200 $ 0 200 400 0 10 20 30 32 40 Q
50
60
65
33
70
80
85
200 400 0 10 20 30 32 40 Q
CONCLUSION MPS A:110 B:32
50
60
65
70
80
85
3.BEP(T) 24.8*1.91+18.78*2.26=89.8
34
35
1.BEP(Q) A:40Q(200+Q(25/(1(10.8))))=0 24.8 B:15Q(100+Q(8/(1(10.85))))=0 18.78 A&B:40Q(200+Q(25/(1(10.8))))=15Q(100+ Q(8/(1(10.85)))) Q=32 2.BEP(S) 24.8*40+18.78*15=$1,273.7
3.BEP(T) 24.8*1.91+18.78*2.26=89.8
36
1.BEP(Q) A:40Q(200+Q(25/(1(10.8))))=0 24.8 B:15Q(100+Q(8/(1(10.85))))=0 18.78 A&B:40Q(200+Q(25/(1(10.8))))=15Q(100+ Q(8/(1(10.85)))) Q=32
MTSH 0n * +1.63 1.00 1.00 +0.62
2.BEP(S) 24.8*40+18.78*15=$1,273.7 3.BEP(T) 24.8*1.91+18.78*2.26=89.8
37
3.BEP(T) 24.8*1.91+18.78*2.26=89.8
38
(T ) T/T T (1. T * 2.T ) 2.T 3.. 4.. )
(1.T
TAC PVA T T T T T T T T T T T T T T T T -T -T -T -T -T -T -T -T -T -T -T
T T T T T T T T T T T T T T T T T T
0 0 0 0 0 0 0 0 0 0 0 0 0 0 100 100 100 100
-T T T T T T T T T T T T T T T T T T T: 1. 2. 3.( ; * ; * : 4/1 eV+ 1 @ VF A -T -T T T T T T T T T T T T T T T T T T
100 20 20 20 0 100 100 0 100 0 100 0 0 0 0 100 0 0
4.T & ( T1 : T:
100 pcs $10/pcs
T (1) 80 pcs 80
T (2) 800
20 pcs 8*
--
100 100 100 100 100 100 100 100 100 100 100 100 100 100 0 T 0 0 0 +T *T +T *T
*T *T
T
*T +T
*T +T
0 80 80 80 100 0 0 100 0 100 0 100 100 100 100 0 100 100
*T T *
*T T T (5)+(6) 12.50
T (3) --
T (5)=(2)/(1) 10.00
T (6)=(4)/(2)-(5) --
(4)=(2)+(3) 1000
200
1000
--
2.50
12.50