Research Article

A Two-Stage Simulated Annealing Algorithm for the Many-to-Many Milk-Run Routing Problem with Pipeline Inventory Cost

Table 2

Results obtained for the three algorithms (TSSALSS, TSSA, and SA).

InstancesTSSALSSTSSASA
AverageMinimumStdNIAverageMinimumStdGap 1NIAverageMinimumStdGap 1NI

S1304.901 297.15 4.41 1.73 30988 302.645 295.69 3.65 1.96 5−0.74%37414 303.769 298.92 2.46 3.12 6−0.37%56618
S2456.536 449.86 3.98 1.88 30988 452.370 444.21 4.83 2.04 6−0.91%37414 455.791 448.72 4.04 3.16 7−0.16%56618
S3602.408 585.28 8.14 5.67 72306 602.332 587.65 9.84 6.83 6−0.01%99770 598.319 584.15 7.82 8.89 4−0.68%152817
S4879.412 848.56 18.20 5.70 72306 876.568 837.68 27.13 7.29 5−0.32%99770 875.906 846.73 19.89 8.61 6−0.40%152817
S5501.301 493.02 5.18 3.59 51647 503.956 490.13 8.55 4.11 30.53%74828 502.876 493.48 5.24 6.02 30.31%114613
S6629.063 612.58 10.24 3.43 51647 630.897 620.04 7.24 4.34 40.29%74828 629.803 614.61 9.64 6.14 30.12%114613
S7934.877 902.45 19.29 4.05 92965 929.226 893.19 24.96 7.62 5−0.60%149655 936.248 906.73 20.39 13.16 20.15%235956
S81239.98 1192.3 27.04 4.47 92965 1244.04 1217.4 19.98 7.31 30.33%149655 1247.59 1216.6 20.09 13.82 30.61%235956
M11788.32 1748.3 33.93 9.44 206589 1790.89 1768.9 12.69 19.35 10.14%374138 1789.84 1760.8 15.76 34.67 20.08%602942
M23056.33 2961.1 46.96 10.38 206589 3099.02 3067.3 20.22 19.58 01.40%374138 3100.79 3047.8 36.31 36.12 11.45%619767
M33362.66 3316.6 34.38 23.01 413178 3423.01 3371.1 32.18 47.55 01.79%872990 3403.08 3351.0 37.11 83.74 11.20%1446124
M44304.45 4244.3 42.61 24.32 413178 4400.65 4343.8 43.99 46.28 02.23%872990 4393.82 4311.3 51.87 84.20 02.08%1459131
M56668.53 6596.3 48.92 73.86 1239535 6757.88 6669.6 55.29 134.65 01.34%2244830 6803.68 6673.4 80.34 233.27 02.03%3810673
M610201.1 1010760.24 76.35 1239535 10415.9 1033886.07 135.77 02.11%2244830 10426.8 1030293.99 239.09 02.21%3796910
M75933.78 5880.7 59.37 74.02 1239535 6025.07 5928.7 60.39 127.23 11.54%2244830 6034.00 5941.9 62.11 226.57 01.69%3796910
M89039.82 8905.8 84.22 79.19 1239535 9192.46 9040.1 122.74 137.51 01.69%2244830 9212.56 9086.4 100.60 256.14 01.91%3860891
M910582.9 10396132.05 160.04 2582364 10790.7 10561173.01 320.22 01.96%4988511 10805.6 10536222.69 570.52 02.10%8804100
M1013712.1 13523137.71 184.77 2788953 14000.7 13810151.68 395.58 02.10%5237937 14005.5 13834133.30 672.36 02.14%9244305
L19829.9 9766.5 58.41 83.20 1342829 9972.3 9813.0 87.24 151.05 01.45%2494256 10033.1 9917.0 88.39 275.78 02.07%4327041
L218127.8 17930119.90 203.29 2995542 18621.3 18342186.38 411.13 02.72%5487363 18809.6 18477273.08 728.70 03.76%9785545
L325307.3 25023170.72 358.27 3098836 26132.2 25663283.87 722.54 03.26%5612075 26134.0 25733209.27 1103.96 03.27%10100378
L444704.2 44276319.65 1532.21 8712249 46402.4 45235730.92 3212.35 03.80%16941776 46353.9 45637503.28 5932.82 03.69%30370067
L520877.3 20651143.83 224.84 3098836 21468.2 21039308.38 423.63 02.83%5612075 21518.3 21356273.78 743.19 03.07%10100378
L639325.9 38912251.02 824.93 8712249 40496.4 40076296.43 1564.54 02.98%16941776 40566.8 40233219.51 2688.31 03.16%30370067
L738951.6 38327389.55 1675.24 10759079 40706.9 391241266.30 3973.80 04.51%19527397 40560.1 39646495.65 7432.02 04.13%34207264
L877932.8 77134472.58 5708.22 29953307 >1000056492589 >1000096608294
L921374.5 21195144.58 259.16 3615309 21933.1 21573271.82 488.21 02.61%6235639 21954.4 21373365.09 882.13 12.71%11222642
L1039113.6 38850210.16 867.88 9801280 40401.4 39762430.52 1631.88 03.29%18244990 40463.4 39831354.59 2982.57 03.45%32706226
L1154512.3 54081373.65 1787.21 11680795 56645.6 548831122.00 4209.09 03.91%20733929 57025.3 56219617.77 8397.48 04.61%35694937
L12110389.7 109834765.05 6045.78 34276626 >1000071917382 >10000121540613