Research Article

Presenting a Multi-Start Hybrid Heuristic for Solving the Problem of Two-Echelon Location-Routing Problem with Simultaneous Pickup and Delivery (2E-LRPSPD)

Table 4

Comparison of proposed heuristic and B&C on Barreto’s LRPSPD instances.

InstanceDSSB&C [34]MHH-PR
Gap (%)CPUGap (%)CPU

Srivastava86_82625.430.000.38625.430.001.09
625.430.000.26625.430.001.03
Perl83_122242.410.000.60242.410.003.05
242.410.000.55242.410.002.21
Gaskell67_215454.480.0013.34454.480.007.51
454.480.008.98454.480.006.08
Gaskell67_225629.510.00109.62629.510.005.17
629.510.0064.99629.510.005.04
Min92_2752998.800.0091.872998.800.004.95
2998.800.00190.622998.800.006.61
Gaskell67_295490.340.006.63490.340.004.65
490.340.006.57490.340.005.99
Gaskell67_325_1563.470.0018.77563.470.006.83
563.470.0027.31563.470.006.98
Gaskell67_325_2507.030.0013.72507.030.005.88
507.030.007.87507.030.005.30
Gaskell67_365494.860.0018.36503.161.687.20
494.860.0018.13501.051.2513.62
Ghristofides69_505576.692.4014400.00612.586.2215.38
578.972.6914400.00600.253.6716.42
Perl83_5515985.562.9414400.00999.061.3757.50
988.063.1414400.001002.171.4355.07
Christofides69_7510888.1610.3314400.00896.510.9447.96
884.008.9014400.00890.800.7762.06
Perl83_8571381.575.8814400.001386.520.36131.55
1368.644.9614400.001412.783.22114.98
Daskin95_888399.1711.2014400.00406.681.88109.69
401.980.0014068.40419.604.38134.31
Christofides69_10010880.187.4514400.00884.160.45151.00
880.896.1714400.00902.042.40115.67

Average2.205768.90814.681.0037.03

In this table, the first column represents the names of the LRPSPD instances. The name of each instance is represented by the coding structure of the author, Author, who generated the instance; year of the instance, Year; the number of customers, ; and the number of depots, (i.e., Author–Year-). The names of instances can not be set in bold.