Ejercicios EXCEL Capítulo 11 Chopra

Ex 11.1

Evaluating Cycle Service Level Given a Replenishment Policy(Example 11.1)Inputs

2,500 2

500 10,000

Reorder Point Increment = 10

Reorder Safety Average AverageInventory Flow Time

5000 0 5000 2.005010 10 5010 2.005020 20 5020 2.015030 30 5030 2.015040 40 5040 2.025050 50 5050 2.025060 60 5060 2.025070 70 5070 2.035080 80 5080 2.035090 90 5090 2.045100 100 5100 2.045110 110 5110 2.045120 120 5120 2.055130 130 5130 2.055140 140 5140 2.065150 150 5150 2.065160 160 5160 2.065170 170 5170 2.075180 180 5180 2.075190 190 5190 2.085200 200 5200 2.085210 210 5210 2.085220 220 5220 2.095230 230 5230 2.095240 240 5240 2.105250 250 5250 2.105260 260 5260 2.105270 270 5270 2.115280 280 5280 2.115290 290 5290 2.125300 300 5300 2.12

Average demand per unit time Lead time, L =SD of demand per unit time

Lot size Q =

Point ROP Inventory ss

Ex 11.1

Reorder Safety Average AverageInventory Flow TimePoint ROP Inventory ss

5310 310 5310 2.125320 320 5320 2.135330 330 5330 2.135340 340 5340 2.145350 350 5350 2.145360 360 5360 2.145370 370 5370 2.155380 380 5380 2.155390 390 5390 2.165400 400 5400 2.165410 410 5410 2.165420 420 5420 2.175430 430 5430 2.175440 440 5440 2.185450 450 5450 2.185460 460 5460 2.185470 470 5470 2.195480 480 5480 2.195490 490 5490 2.205500 500 5500 2.205510 510 5510 2.205520 520 5520 2.215530 530 5530 2.215540 540 5540 2.225550 550 5550 2.225560 560 5560 2.225570 570 5570 2.235580 580 5580 2.235590 590 5590 2.245600 600 5600 2.245610 610 5610 2.245620 620 5620 2.255630 630 5630 2.255640 640 5640 2.265650 650 5650 2.265660 660 5660 2.265670 670 5670 2.275680 680 5680 2.275690 690 5690 2.285700 700 5700 2.285710 710 5710 2.28

Ex 11.1


5720 720 5720 2.295730 730 5730 2.295740 740 5740 2.305750 750 5750 2.305760 760 5760 2.305770 770 5770 2.315780 780 5780 2.315790 790 5790 2.325800 800 5800 2.325810 810 5810 2.325820 820 5820 2.335830 830 5830 2.335840 840 5840 2.345850 850 5850 2.345860 860 5860 2.345870 870 5870 2.355880 880 5880 2.355890 890 5890 2.365900 900 5900 2.365910 910 5910 2.365920 920 5920 2.375930 930 5930 2.375940 940 5940 2.385950 950 5950 2.385960 960 5960 2.385970 970 5970 2.395980 980 5980 2.395990 990 5990 2.406000 1000 6000 2.406010 1010 6010 2.406020 1020 6020 2.416030 1030 6030 2.416040 1040 6040 2.426050 1050 6050 2.426060 1060 6060 2.426070 1070 6070 2.436080 1080 6080 2.436090 1090 6090 2.446100 1100 6100 2.446110 1110 6110 2.446120 1120 6120 2.45

Ex 11.1


6130 1130 6130 2.456140 1140 6140 2.466150 1150 6150 2.466160 1160 6160 2.466170 1170 6170 2.476180 1180 6180 2.476190 1190 6190 2.486200 1200 6200 2.486210 1210 6210 2.486220 1220 6220 2.496230 1230 6230 2.496240 1240 6240 2.506250 1250 6250 2.506260 1260 6260 2.506270 1270 6270 2.516280 1280 6280 2.516290 1290 6290 2.526300 1300 6300 2.526310 1310 6310 2.526320 1320 6320 2.536330 1330 6330 2.536340 1340 6340 2.546350 1350 6350 2.546360 1360 6360 2.546370 1370 6370 2.556380 1380 6380 2.556390 1390 6390 2.566400 1400 6400 2.566410 1410 6410 2.566420 1420 6420 2.576430 1430 6430 2.576440 1440 6440 2.586450 1450 6450 2.586460 1460 6460 2.586470 1470 6470 2.596480 1480 6480 2.596490 1490 6490 2.606500 1500 6500 2.606510 1510 6510 2.606520 1520 6520 2.616530 1530 6530 2.61

Ex 11.1


6540 1540 6540 2.626550 1550 6550 2.626560 1560 6560 2.626570 1570 6570 2.636580 1580 6580 2.636590 1590 6590 2.646600 1600 6600 2.646610 1610 6610 2.646620 1620 6620 2.656630 1630 6630 2.656640 1640 6640 2.666650 1650 6650 2.666660 1660 6660 2.666670 1670 6670 2.676680 1680 6680 2.676690 1690 6690 2.686700 1700 6700 2.686710 1710 6710 2.686720 1720 6720 2.696730 1730 6730 2.696740 1740 6740 2.706750 1750 6750 2.706760 1760 6760 2.706770 1770 6770 2.716780 1780 6780 2.716790 1790 6790 2.726800 1800 6800 2.726810 1810 6810 2.726820 1820 6820 2.736830 1830 6830 2.736840 1840 6840 2.746850 1850 6850 2.746860 1860 6860 2.746870 1870 6870 2.756880 1880 6880 2.756890 1890 6890 2.76

Ex 11.2

Evaluating Cycle Service Level Given a Replenishment Policy(Example 11.2)Inputs

2,500 2

500 10,000

Intermediate calculation 5,000 707


Reorder Safety Cycle Service Average AverageInventory Flow Time

5000 0 0.500 5000 2.005010 10 0.506 5010 2.005020 20 0.511 5020 2.015030 30 0.517 5030 2.015040 40 0.523 5040 2.025050 50 0.528 5050 2.025060 60 0.534 5060 2.025070 70 0.539 5070 2.035080 80 0.545 5080 2.035090 90 0.551 5090 2.045100 100 0.556 5100 2.045110 110 0.562 5110 2.045120 120 0.567 5120 2.055130 130 0.573 5130 2.055140 140 0.578 5140 2.065150 150 0.584 5150 2.065160 160 0.590 5160 2.065170 170 0.595 5170 2.075180 180 0.600 5180 2.075190 190 0.606 5190 2.085200 200 0.611 5200 2.085210 210 0.617 5210 2.085220 220 0.622 5220 2.095230 230 0.628 5230 2.095240 240 0.633 5240 2.105250 250 0.638 5250 2.105260 260 0.643 5260 2.10

Average demand per unit time R =Lead time, L =SD of demand per unit time R =

Lot size Q =

Mean demand during lead time RL =SD of demand during lead time L =

Point ROP Inventory ss Level (CSL)

Ex 11.2

Reorder Safety Cycle Service Average AverageInventory Flow TimePoint ROP Inventory ss Level (CSL)

5270 270 0.649 5270 2.115280 280 0.654 5280 2.115290 290 0.659 5290 2.125300 300 0.664 5300 2.125310 310 0.669 5310 2.125320 320 0.675 5320 2.135330 330 0.680 5330 2.135340 340 0.685 5340 2.145350 350 0.690 5350 2.145360 360 0.695 5360 2.145370 370 0.700 5370 2.155380 380 0.705 5380 2.155390 390 0.709 5390 2.165400 400 0.714 5400 2.165410 410 0.719 5410 2.165420 420 0.724 5420 2.175430 430 0.728 5430 2.175440 440 0.733 5440 2.185450 450 0.738 5450 2.185460 460 0.742 5460 2.185470 470 0.747 5470 2.195480 480 0.751 5480 2.195490 490 0.756 5490 2.205500 500 0.760 5500 2.205510 510 0.765 5510 2.205520 520 0.769 5520 2.215530 530 0.773 5530 2.215540 540 0.777 5540 2.225550 550 0.782 5550 2.225560 560 0.786 5560 2.225570 570 0.790 5570 2.235580 580 0.794 5580 2.235590 590 0.798 5590 2.245600 600 0.802 5600 2.245610 610 0.806 5610 2.245620 620 0.810 5620 2.255630 630 0.814 5630 2.255640 640 0.817 5640 2.265650 650 0.821 5650 2.265660 660 0.825 5660 2.265670 670 0.828 5670 2.27

Ex 11.2


5680 680 0.832 5680 2.275690 690 0.835 5690 2.285700 700 0.839 5700 2.285710 710 0.842 5710 2.285720 720 0.846 5720 2.295730 730 0.849 5730 2.295740 740 0.852 5740 2.305750 750 0.856 5750 2.305760 760 0.859 5760 2.305770 770 0.862 5770 2.315780 780 0.865 5780 2.315790 790 0.868 5790 2.325800 800 0.871 5800 2.325810 810 0.874 5810 2.325820 820 0.877 5820 2.335830 830 0.880 5830 2.335840 840 0.883 5840 2.345850 850 0.885 5850 2.345860 860 0.888 5860 2.345870 870 0.891 5870 2.355880 880 0.893 5880 2.355890 890 0.896 5890 2.365900 900 0.898 5900 2.365910 910 0.901 5910 2.365920 920 0.903 5920 2.375930 930 0.906 5930 2.375940 940 0.908 5940 2.385950 950 0.910 5950 2.385960 960 0.913 5960 2.385970 970 0.915 5970 2.395980 980 0.917 5980 2.395990 990 0.919 5990 2.406000 1000 0.921 6000 2.406010 1010 0.923 6010 2.406020 1020 0.925 6020 2.416030 1030 0.927 6030 2.416040 1040 0.929 6040 2.426050 1050 0.931 6050 2.426060 1060 0.933 6060 2.426070 1070 0.935 6070 2.436080 1080 0.937 6080 2.43

Ex 11.2


6090 1090 0.938 6090 2.446100 1100 0.940 6100 2.446110 1110 0.942 6110 2.446120 1120 0.943 6120 2.456130 1130 0.945 6130 2.456140 1140 0.947 6140 2.466150 1150 0.948 6150 2.466160 1160 0.950 6160 2.466170 1170 0.951 6170 2.476180 1180 0.952 6180 2.476190 1190 0.954 6190 2.486200 1200 0.955 6200 2.486210 1210 0.956 6210 2.486220 1220 0.958 6220 2.496230 1230 0.959 6230 2.496240 1240 0.960 6240 2.506250 1250 0.961 6250 2.506260 1260 0.963 6260 2.506270 1270 0.964 6270 2.516280 1280 0.965 6280 2.516290 1290 0.966 6290 2.526300 1300 0.967 6300 2.526310 1310 0.968 6310 2.526320 1320 0.969 6320 2.536330 1330 0.970 6330 2.536340 1340 0.971 6340 2.546350 1350 0.972 6350 2.546360 1360 0.973 6360 2.546370 1370 0.974 6370 2.556380 1380 0.975 6380 2.556390 1390 0.975 6390 2.566400 1400 0.976 6400 2.566410 1410 0.977 6410 2.566420 1420 0.978 6420 2.576430 1430 0.978 6430 2.576440 1440 0.979 6440 2.586450 1450 0.980 6450 2.586460 1460 0.981 6460 2.586470 1470 0.981 6470 2.596480 1480 0.982 6480 2.596490 1490 0.982 6490 2.60

Ex 11.2


6500 1500 0.983 6500 2.606510 1510 0.984 6510 2.606520 1520 0.984 6520 2.616530 1530 0.985 6530 2.616540 1540 0.985 6540 2.626550 1550 0.986 6550 2.626560 1560 0.986 6560 2.626570 1570 0.987 6570 2.636580 1580 0.987 6580 2.636590 1590 0.988 6590 2.646600 1600 0.988 6600 2.646610 1610 0.989 6610 2.646620 1620 0.989 6620 2.656630 1630 0.989 6630 2.656640 1640 0.990 6640 2.666650 1650 0.990 6650 2.666660 1660 0.991 6660 2.666670 1670 0.991 6670 2.676680 1680 0.991 6680 2.676690 1690 0.992 6690 2.686700 1700 0.992 6700 2.686710 1710 0.992 6710 2.686720 1720 0.993 6720 2.696730 1730 0.993 6730 2.696740 1740 0.993 6740 2.706750 1750 0.993 6750 2.706760 1760 0.994 6760 2.706770 1770 0.994 6770 2.716780 1780 0.994 6780 2.716790 1790 0.994 6790 2.726800 1800 0.995 6800 2.726810 1810 0.995 6810 2.726820 1820 0.995 6820 2.736830 1830 0.995 6830 2.736840 1840 0.995 6840 2.746850 1850 0.996 6850 2.746860 1860 0.996 6860 2.746870 1870 0.996 6870 2.756880 1880 0.996 6880 2.756890 1890 0.996 6890 2.76

Ex 11.3

Page 11

Evaluating Service Level Given Safety Inventory(Example 11.3)Inputs

2,500 2

500 10,000

Intermediate calculation5000

707


Reorder Safety Cycle Service Average Average Fill RateInventory Flow Time ESC fr

5000 0 0.500 5000 2 282.09 0.97185010 10 0.506 5010 2.004 277.12 0.97235020 20 0.511 5020 2.008 272.21 0.97285030 30 0.517 5030 2.012 267.35 0.97335040 40 0.523 5040 2.016 262.55 0.97375050 50 0.528 5050 2.02 257.80 0.97425060 60 0.534 5060 2.024 253.11 0.97475070 70 0.539 5070 2.028 248.48 0.97525080 80 0.545 5080 2.032 243.90 0.97565090 90 0.551 5090 2.036 239.38 0.97615100 100 0.556 5100 2.04 234.91 0.97655110 110 0.562 5110 2.044 230.50 0.97695120 120 0.567 5120 2.048 226.15 0.97745130 130 0.573 5130 2.052 221.85 0.97785140 140 0.578 5140 2.056 217.61 0.97825150 150 0.584 5150 2.06 213.42 0.97875160 160 0.590 5160 2.064 209.29 0.97915170 170 0.595 5170 2.068 205.21 0.97955180 180 0.600 5180 2.072 201.19 0.97995190 190 0.606 5190 2.076 197.22 0.98035200 200 0.611 5200 2.08 193.30 0.98075210 210 0.617 5210 2.084 189.44 0.98115220 220 0.622 5220 2.088 185.64 0.98145230 230 0.628 5230 2.092 181.89 0.98185240 240 0.633 5240 2.096 178.19 0.98225250 250 0.638 5250 2.1 174.54 0.98255260 260 0.643 5260 2.104 170.95 0.9829

Average demand per unit time R =Lead time, L =SD of demand per unit time R =

Lot size Q =


Point ROP Inventory ss Level (CSL)

Ex 11.3

Page 12

Reorder Safety Cycle Service Average Average Fill RateInventory Flow Time ESC frPoint ROP Inventory ss Level (CSL)

5270 270 0.649 5270 2.108 167.41 0.98335280 280 0.654 5280 2.112 163.93 0.98365290 290 0.659 5290 2.116 160.49 0.98405300 300 0.664 5300 2.12 157.11 0.98435310 310 0.669 5310 2.124 153.78 0.98465320 320 0.675 5320 2.128 150.50 0.98505330 330 0.680 5330 2.132 147.27 0.98535340 340 0.685 5340 2.136 144.09 0.98565350 350 0.690 5350 2.14 140.96 0.98595360 360 0.695 5360 2.144 137.88 0.98625370 370 0.700 5370 2.148 134.86 0.98655380 380 0.705 5380 2.152 131.88 0.98685390 390 0.709 5390 2.156 128.95 0.98715400 400 0.714 5400 2.16 126.06 0.98745410 410 0.719 5410 2.164 123.23 0.98775420 420 0.724 5420 2.168 120.44 0.98805430 430 0.728 5430 2.172 117.70 0.98825440 440 0.733 5440 2.176 115.01 0.98855450 450 0.738 5450 2.18 112.37 0.98885460 460 0.742 5460 2.184 109.77 0.98905470 470 0.747 5470 2.188 107.21 0.98935480 480 0.751 5480 2.192 104.70 0.98955490 490 0.756 5490 2.196 102.24 0.98985500 500 0.760 5500 2.2 99.82 0.99005510 510 0.765 5510 2.204 97.45 0.99035520 520 0.769 5520 2.208 95.11 0.99055530 530 0.773 5530 2.212 92.82 0.99075540 540 0.777 5540 2.216 90.58 0.99095550 550 0.782 5550 2.22 88.37 0.99125560 560 0.786 5560 2.224 86.21 0.99145570 570 0.790 5570 2.228 84.09 0.99165580 580 0.794 5580 2.232 82.01 0.99185590 590 0.798 5590 2.236 79.97 0.99205600 600 0.802 5600 2.24 77.97 0.99225610 610 0.806 5610 2.244 76.01 0.99245620 620 0.810 5620 2.248 74.08 0.99265630 630 0.814 5630 2.252 72.20 0.99285640 640 0.817 5640 2.256 70.35 0.99305650 650 0.821 5650 2.26 68.55 0.99315660 660 0.825 5660 2.264 66.77 0.9933

Ex 11.3

Page 13


5670 670 0.828 5670 2.268 65.04 0.99355680 680 0.832 5680 2.272 63.34 0.99375690 690 0.835 5690 2.276 61.68 0.99385700 700 0.839 5700 2.28 60.05 0.99405710 710 0.842 5710 2.284 58.46 0.99425720 720 0.846 5720 2.288 56.90 0.99435730 730 0.849 5730 2.292 55.37 0.99455740 740 0.852 5740 2.296 53.88 0.99465750 750 0.856 5750 2.3 52.42 0.99485760 760 0.859 5760 2.304 50.99 0.99495770 770 0.862 5770 2.308 49.59 0.99505780 780 0.865 5780 2.312 48.23 0.99525790 790 0.868 5790 2.316 46.89 0.99535800 800 0.871 5800 2.32 45.59 0.99545810 810 0.874 5810 2.324 44.31 0.99565820 820 0.877 5820 2.328 43.07 0.99575830 830 0.880 5830 2.332 41.85 0.99585840 840 0.883 5840 2.336 40.66 0.99595850 850 0.885 5850 2.34 39.50 0.99605860 860 0.888 5860 2.344 38.37 0.99625870 870 0.891 5870 2.348 37.26 0.99635880 880 0.893 5880 2.352 36.18 0.99645890 890 0.896 5890 2.356 35.13 0.99655900 900 0.898 5900 2.36 34.10 0.99665910 910 0.901 5910 2.364 33.10 0.99675920 920 0.903 5920 2.368 32.12 0.99685930 930 0.906 5930 2.372 31.17 0.99695940 940 0.908 5940 2.376 30.24 0.99705950 950 0.910 5950 2.38 29.33 0.99715960 960 0.913 5960 2.384 28.44 0.99725970 970 0.915 5970 2.388 27.58 0.99725980 980 0.917 5980 2.392 26.74 0.99735990 990 0.919 5990 2.396 25.92 0.99746000 1000 0.921 6000 2.4 25.13 0.99756010 1010 0.923 6010 2.404 24.35 0.99766020 1020 0.925 6020 2.408 23.60 0.99766030 1030 0.927 6030 2.412 22.86 0.99776040 1040 0.929 6040 2.416 22.14 0.99786050 1050 0.931 6050 2.42 21.45 0.99796060 1060 0.933 6060 2.424 20.77 0.9979

Ex 11.3

Page 14


6070 1070 0.935 6070 2.428 20.11 0.99806080 1080 0.937 6080 2.432 19.46 0.99816090 1090 0.938 6090 2.436 18.84 0.99816100 1100 0.940 6100 2.44 18.23 0.99826110 1110 0.942 6110 2.444 17.64 0.99826120 1120 0.943 6120 2.448 17.07 0.99836130 1130 0.945 6130 2.452 16.51 0.99836140 1140 0.947 6140 2.456 15.97 0.99846150 1150 0.948 6150 2.46 15.44 0.99856160 1160 0.950 6160 2.464 14.93 0.99856170 1170 0.951 6170 2.468 14.43 0.99866180 1180 0.952 6180 2.472 13.95 0.99866190 1190 0.954 6190 2.476 13.48 0.99876200 1200 0.955 6200 2.48 13.02 0.99876210 1210 0.956 6210 2.484 12.58 0.99876220 1220 0.958 6220 2.488 12.15 0.99886230 1230 0.959 6230 2.492 11.74 0.99886240 1240 0.960 6240 2.496 11.33 0.99896250 1250 0.961 6250 2.5 10.94 0.99896260 1260 0.963 6260 2.504 10.56 0.99896270 1270 0.964 6270 2.508 10.20 0.99906280 1280 0.965 6280 2.512 9.84 0.99906290 1290 0.966 6290 2.516 9.49 0.99916300 1300 0.967 6300 2.52 9.16 0.99916310 1310 0.968 6310 2.524 8.83 0.99916320 1320 0.969 6320 2.528 8.52 0.99916330 1330 0.970 6330 2.532 8.21 0.99926340 1340 0.971 6340 2.536 7.92 0.99926350 1350 0.972 6350 2.54 7.63 0.99926360 1360 0.973 6360 2.544 7.36 0.99936370 1370 0.974 6370 2.548 7.09 0.99936380 1380 0.975 6380 2.552 6.83 0.99936390 1390 0.975 6390 2.556 6.58 0.99936400 1400 0.976 6400 2.56 6.34 0.99946410 1410 0.977 6410 2.564 6.10 0.99946420 1420 0.978 6420 2.568 5.87 0.99946430 1430 0.978 6430 2.572 5.65 0.99946440 1440 0.979 6440 2.576 5.44 0.99956450 1450 0.980 6450 2.58 5.24 0.99956460 1460 0.981 6460 2.584 5.04 0.9995

Ex 11.3

Page 15


6470 1470 0.981 6470 2.588 4.85 0.99956480 1480 0.982 6480 2.592 4.66 0.99956490 1490 0.982 6490 2.596 4.48 0.99966500 1500 0.983 6500 2.6 4.31 0.99966510 1510 0.984 6510 2.604 4.14 0.99966520 1520 0.984 6520 2.608 3.98 0.99966530 1530 0.985 6530 2.612 3.83 0.99966540 1540 0.985 6540 2.616 3.68 0.99966550 1550 0.986 6550 2.62 3.53 0.99966560 1560 0.986 6560 2.624 3.40 0.99976570 1570 0.987 6570 2.628 3.26 0.99976580 1580 0.987 6580 2.632 3.13 0.99976590 1590 0.988 6590 2.636 3.01 0.99976600 1600 0.988 6600 2.64 2.89 0.99976610 1610 0.989 6610 2.644 2.77 0.99976620 1620 0.989 6620 2.648 2.66 0.99976630 1630 0.989 6630 2.652 2.55 0.99976640 1640 0.990 6640 2.656 2.45 0.99986650 1650 0.990 6650 2.66 2.35 0.99986660 1660 0.991 6660 2.664 2.25 0.99986670 1670 0.991 6670 2.668 2.16 0.99986680 1680 0.991 6680 2.672 2.07 0.99986690 1690 0.992 6690 2.676 1.98 0.99986700 1700 0.992 6700 2.68 1.90 0.99986710 1710 0.992 6710 2.684 1.82 0.99986720 1720 0.993 6720 2.688 1.74 0.99986730 1730 0.993 6730 2.692 1.67 0.99986740 1740 0.993 6740 2.696 1.60 0.99986750 1750 0.993 6750 2.7 1.53 0.99986760 1760 0.994 6760 2.704 1.47 0.99996770 1770 0.994 6770 2.708 1.40 0.99996780 1780 0.994 6780 2.712 1.34 0.99996790 1790 0.994 6790 2.716 1.29 0.99996800 1800 0.995 6800 2.72 1.23 0.99996810 1810 0.995 6810 2.724 1.18 0.99996820 1820 0.995 6820 2.728 1.12 0.99996830 1830 0.995 6830 2.732 1.08 0.99996840 1840 0.995 6840 2.736 1.03 0.99996850 1850 0.996 6850 2.74 0.98 0.99996860 1860 0.996 6860 2.744 0.94 0.9999

Ex 11.3

Page 16


6870 1870 0.996 6870 2.748 0.90 0.99996880 1880 0.996 6880 2.752 0.86 0.99996890 1890 0.996 6890 2.756 0.82 0.9999

ss-chart

Page 17

0 60

120

180

240

300

360

420

480

540

600

660

720

780

840

900

960

1020

10

80

1140

12

00

1260

13

20

1380

14

40

1500

15

60

1620

16

80

1740

18

00

1860

-

0.200

0.400

0.600

0.800

1.000

1.200

Service Level vs. Safety Inventory

Cycle Service Level (CSL)

Safety Inventory

Serv

ice

Leve

l

Ex 11.4

Evaluating Safety Inventory Given Cycle Service Level (Example 11.4)Input

2500 boxes500

2 weeksDesired cycle service level = 0.9

VariableEstimated safety inventory = 0

50005000

707ResultImplied Service Level = 0.5000

Evaluating Safety Inventory Given Cycle Service Level (Example 8.4)Input

2500 boxes500

2 weeksDesired cycle service level = 0.9

SolutionIntermediate calculation

5000 707

Result

Demand per period (week), R =Standard deviation of demand, R =Replenishment lead time, L =

Reorder point, ROP=Mean demand during lead time RL =SD of demand during lead time L =



Ex 11.4

Required safety inventory = 906

Ex 11.5

Evaluating Safety Inventory Given Fill Rate (Example 11.5)Input

2500 boxes500

2 weeksDesired fill rate = 0.975

VariableEstimated safety inventory = 67

5067 5000

###10000

250ResultImplied Fill Rate = 0.9750


Reorder point, ROP =Mean demand during lead time RL =SD of demand during lead time L =Lot size, Q =Expected shortage per cycle, ESC =

Ex 11.5

Evaluating Safety Inventory Given Fill Rate (Example 8.5)Input

2500 boxes500

2 weeksDesired fill rate = 0.975

ESC Goal (from fill rate) = 250 (equation 8.5)

Input Variablefr Q ss

0.9750 707 10,000 67Formula

ESC250


L

Adjust ss to achieve desired ESC.

Check based on desired fill rate and safety inventory level.

Ex 11.5

Ex 11.6

Evaluating the impact of Lead Time Uncertainty on Safety Inventory (Example 11.6)Input

2500 drives500

7 days7 days

Desired cycle service level, CSL = 0.90

SolutionIntermediate calculation

17500 17,550

Resulting Safety Inventory LevelEstimated safety inventory (units) = 22,491 # of days' demand = 9.00

Demand per period (day), R =Standard deviation of demand, R =Avg. replenishment lead time, L =Standard deviation of lead time, sL =


Ex. 11.7

Value of Aggregation (Example 11.7)25 5 2 0

Desired cycle service level, CSL = 0.90 0.00

Number of retail outlets 4.00 Cost per Vehicle $ 20,000 Inventory Holding Cost 0.20

Intermediate calculation100

10 50 200

7.07 14.14

Resulting Safety Inventory Level at Each Retail OutletEstimated safety inventory (units) = 9.06 0 # of weeks' demand = 0.36 0

Total Safety Inventory RequiredTotal Safety Inventory Required 36.25 18.12# of weeks' demand = 1.45 0.72

Safety Inventory Savings through AggregationUnit Savings 18.12Inventory Savings $ 362,478 Annual Holding Cost Savings $ 72,496

Demand per period (weekly) per location, Ri (cars)=Standard deviation of demand, R =Ave replensihment lead time, L (weeks)=Standard deviation of lead time, sL (weeks)=

Correlation Coefficient,

without aggregation

with aggregation

Mean Weekly Demand, RC

Standard Deviation of demand, RC


ex. 11.10

Page 26

Evaluating Safety inventory for periodic review policies (Example 11.10)Input

2500 500

2 4

Desired cycle service level = 0.90

Intermediate calculation Periodic 15,000 1,225

ResultDesired safety inventory = 1,570

16,570

Demand per period (week), R (boxes) =Standard deviation of demand, R =Replenishment lead time, L (weeks)=Review interval, T (weeks)=

Mean demand during time T+L, RT+L =SD of demand during time T+L, T+L =

Order up to level, OUL =

Ex 11.1Ex 11.2Ex 11.3ss-chartEx 11.4Ex 11.5Ex 11.6Ex. 11.7ex. 11.10

Ejercicios EXCEL Capítulo 11 Chopra

Documents