## 5 Conclusions  
1. A high negative correlation was found between the rate of change of humidity and rate of change of temperature of the bay. The ratio of the slope of the relational expression of the rate of change of temperature and humidity \(q_{i}\) of a particular bay to rate of change associated with the thermometer shelter \(q_{0}\) is a fixed value \(p_{i}\), called the bay humidity characteristic coefficient. This value reflects the dimensionless response of the local humidity of the bay to local temperature changes.  
\begin{table}
\begin{tabular}{l c c c c c c} \hline \hline \multicolumn{1}{c}{\multirow{2}{*}{**Statistical Objects**}} & \multicolumn{3}{c}{**Humidity/\% RH**} & \multicolumn{3}{c}{**Deviation/\% RH**} & \multicolumn{1}{c}{**Correlation**} \\ \cline{2-7}  & **Maximum** & **Minimum** & **Average** & **Maximum** & **Average** & **Coefficient** \\ \hline
**Measured humidity value of kerosene tank** & 68.35 & 39.11 & 54.96 & / & / & / \\ \hline
**Predicted humidity value of kerosene tank** & 71.96 & 39.12 & 58.17 & 10.3 & 4.0 & 0.878 \\ \hline
**Predicted humidity value of kerosene tank** & 68.53 & 37.05 & 55.77 & 9.4 & 3.2 & 0.925 \\ \hline
**Measured humidity value of tail bottom** & 75.08 & 28.68 & 53.10 & / & / & / \\ \hline
**Predicted humidity value of tail bottom** & 75.79 & 30.81 & 53.56 & 15.2 & 4.4 & 0.905 \\ \hline
**Predicted humidity value of tail bottom** & 65.88 & 28.76 & 50.71 & 17.6 & 4.2 & 0.882 \\ \hline
**Measured humidity value of exhaust nozzle** & 71.54 & 34.78 & 53.95 & / & / & / \\ \hline
**Predicted humidity value of exhaust nozzle** & 75.65 & 28.88 & 56.30 & 12.5 & 7.3 & 0.851 \\ \hline
**Predicted humidity value of exhaust nozzle** & 72.56 & 27.02 & 54.01 & 12.2 & 7.1 & 0.872 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Statistics of measured and predicted humidity values.  
2. Different aircraft bays in the open/closed state may differ in terms of humidity, however, sealing has a major influence on local humidity. Better sealing of the bay will result in lower values of the corresponding HCC \(p_{i}\) and the overall humidity level will also be lower.
3. Two bay local humidity models were established by using the ambient humidity and temperature (measured at the thermometer shelter) as independent variables and incorporating a number of influential parameters such as the structural coefficient \(m_{i}\), illumination coefficient \(s_{i}\), and HCC \(p_{i}\).
4. Values of HCCs of different bays were determined through statistical analysis and, based on this, the aircraft bays were classified into three types. A comparison between measured data and model data suggests the average deviation of the model proposed in this paper is less than or equal to 7.3% RH.  
Conceptualization, T.Z. and Y.H.; Methodology, T.Z.; Validation, T.Z., X.D. and B.M.; Formal Analysis, T.Z. and S.Z.; Investigation, T.Z.; Writing-Original Draft Preparation, T.Z.; Writing-Review & Editing, T.Z. and S.Z.; Project Administration, T.Z.  
This research was funded by National Natural Science Foundation of China grant number 51475470, China Postdoctoral Science Foundation grant number 2017M623418 and Basic Research Project of Natural Science in Shaanxi Province grant number 2018 JC5012.  
The authors declare no conflicts of interest.