## 7 Discussion  
It is well known that the feasibility of results can be confirmed by the applied evaluation method. In this subsection, an evaluation was performed with the TOPSIS to validate the rationality and accuracy of the proposed GRA-TOPSIS method. Table 4 indicates the comparison results of the two different methods. Figure 7: Topological map of location of consolidation centers. It can be seen that Wuhan, Chongqing, Guangzhou, Tianjin, Shanghai, and Yantai were always the best candidate cities for consolidation centers in the integrated transportation network. In contrast, Zhengzhou, Urumqi, Shijiazhuang, Yinchuan, Changchun, Taiyuan, and Hohhot were all the least suitable locations for consolidation centers as indicated by the comparison of the two methods. Moreover, some cities such as Xi'an, Harbin, Lanzhou, Kunming, Xiamen, Dongguan, Xining, Shenzhen, Chengdu, and others showed significant changes when their results were compared. The reasons for the above situation are the limited transportation modes or routes, and the results could be reflected by the core ideas of these two methods. Specifically, the GRA-TOPSIS approach focuses on the distance \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Number**} & \multirow{2}{*}{**City**} & \multicolumn{2}{c}{**GRA-TOPSIS**} & \multicolumn{2}{c}{**TOPSIS**} \\ \cline{3-6}  & & **Value** & **Ranking** & **Value** & **Ranking** \\ \hline
1 & Chongqing & 0.537127 & 2 & 0.457012 & 3 \\
2 & Wuhan & 0.545447 & 1 & 0.486452 & 1 \\
3 & Zhengzhou & 0.401084 & 34 & 0.27509 & 37 \\
4 & Suzhou & 0.450306 & 24 & 0.306019 & 29 \\
5 & Guangzhou & 0.515681 & 5 & 0.453044 & 4 \\
6 & Xi’an & 0.468879 & 19 & 0.428785 & 6 \\
7 & Hefei & 0.495783 & 9 & 0.380365 & 11 \\
8 & Shenyang & 0.395705 & 37 & 0.303452 & 30 \\
9 & Ningbo & 0.47054 & 18 & 0.320886 & 24 \\
10 & Changsha & 0.454045 & 23 & 0.306945 & 28 \\
11 & Lianyungang & 0.497178 & 8 & 0.374032 & 13 \\
12 & Urumqi & 0.37025 & 44 & 0.23912 & 42 \\
13 & Harbin & 0.394531 & 38 & 0.32307 & 22 \\
14 & Lanzhou & 0.42458 & 32 & 0.319028 & 25 \\
15 & Qingdao & 0.473226 & 16 & 0.321006 & 23 \\
16 & Kunming & 0.4357 & 28 & 0.343287 & 17 \\
17 & Xiamen & 0.449684 & 25 & 0.284713 & 35 \\
18 & Changchun & 0.38529 & 41 & 0.275626 & 36 \\
19 & Nanchang & 0.478111 & 15 & 0.329265 & 20 \\
20 & Dalian & 0.494194 & 10 & 0.404388 & 8 \\
21 & Dongguan & 0.435441 & 29 & 0.350229 & 16 \\
22 & Nanjing & 0.492293 & 11 & 0.356334 & 15 \\
23 & Xining & 0.394515 & 39 & 0.319023 & 26 \\
24 & Tianjin & 0.537 & 3 & 0.465946 & 2 \\
25 & Taiyuan & 0.39277 & 40 & 0.252404 & 41 \\
26 & Shenzhen & 0.465798 & 20 & 0.299306 & 31 \\
27 & Jinan & 0.39833 & 36 & 0.290313 & 33 \\
28 & Shanghai & 0.52019 & 4 & 0.437888 & 5 \\
29 & Tangshan & 0.487521 & 12 & 0.386399 & 9 \\
30 & Shijiazhuang & 0.374376 & 43 & 0.219985 & 44 \\
31 & Chengdu & 0.434533 & 30 & 0.361857 & 14 \\
32 & Yinchuan & 0.398694 & 35 & 0.271357 & 39 \\
33 & Nanning & 0.484117 & 14 & 0.340074 & 18 \\
34 & Hohhot & 0.378585 & 42 & 0.225792 & 43 \\
35 & Hangzhou & 0.504626 & 7 & 0.381728 & 10 \\
36 & Fuzhou & 0.463257 & 21 & 0.29892 & 32 \\
37 & Guiyang & 0.429311 & 31 & 0.32843 & 21 \\
38 & Beijing & 0.416231 & 33 & 0.314666 & 27 \\
39 & Xuzhou & 0.458418 & 22 & 0.286317 & 34 \\
40 & Quanzhou & 0.443887 & 27 & 0.274308 & 38 \\
41 & Jiujiang & 0.485931 & 13 & 0.337719 & 19 \\
42 & Yantai & 0.507155 & 6 & 0.419587 & 7 \\
43 & Liuzhou & 0.473085 & 17 & 0.378515 & 12 \\
44 & Wuxi & 0.445269 & 26 & 0.260848 & 40 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Ranking results for different methods. between alternative solutions and the connection between standards. The TOPSIS mainly considers the distance between alternative reference schemes and the best reference scheme. Additionally, to compare the result obtained using the two methods, [PERSON]'s tau correlation coefficient (KTC) was applied to study the difference in accuracy between the two methods [39]. The value of the calculated KTC of the two methods was 0.661734.