## 5 Conclusions  
In this paper, a time-varying global reliability analysis method for in-service transmission towers based on the HM-IMEM is proposed and verified by an actual engineering example. The main conclusions can be drawn as follows:  
Figure 5: Time-varying reliability index of the in-service transmission tower. Figure 6: PDF for different tr. 1. The time-varying equivalent performance function of the in-service transmission tower is established based on the resistance degradation model of steel members and the random equivalent static wind loads;
2. A high-order moments-based improved maximum entropy method for time-varying global reliability analysis of the in-service transmission tower is developed;
3. The MCS is used to calculate the reliability index at a typical time as the standard solution. The relative error of the reliability results of the proposed method is just 0.11%, which demonstrates that the proposed method can provide fairly high accuracy for reliability results;
4. The proposed method has high computational efficiency and much lower computational cost than MCS;
5. The reliability index of the in-service transmission tower is significantly reduced after a certain period of time, and it is necessary to analyze the time-varying reliability of the in-service transmission tower to evaluate its safety status. Conceptualization, C.L. and T.W. ; Methodology, C.L. and T.W. ; Software, Z.T. ; Data curation, Z.T. ; Writing--Original draft preparation, C.L. ; Writing--Review and editing, C.L. and T.W. ; Supervision, T.W. ; Project administration, Z.L. ; Funding acquisition, Z.L. All authors have read and agreed to the published version of the manuscript. This research was funded by [NSFC-JSPS China-Japan Scientific Cooperation Project] grant number [No. 51611140123], and was funded by [Special Postdoctoral Support Project of Chongqing Research Institute of HIT (Life-cycle reliability assessment of the power transmission tower in the mountainous area under the wind-ice disaster)]. Not applicable. The data used to support the findings of this study are included in the article. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. * (14) [PERSON]; [PERSON]; [PERSON]; [PERSON] A unified approach for time-invariant and time-variant reliability-based design optimization with multiple most probable points. _Mech. Syst. Signal Process._**2022**, _177_, 109176. [CrossRef]
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