## 3 The Objective Electromagnetic Environmental Effects Assessment
### Grey Theory and the Analytical Hierarchy Process
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Main Method**} & \multicolumn{2}{c}{**Evaluation Indexes**} & \multicolumn{2}{c}{**Complexity Grade and Evaluation Criteria**} & \multirow{2}{*}{**Weighting**} \\ \cline{2-3} \cline{5-6}  & **Macro Aspect** & & & & \\ \hline \multirow{6}{*}{Method 1 [24]} & \multirow{6}{*}{TO, FO, SO, AP} & \multirow{6}{*}{WE} & C = TO \(\times\) FO \(\times\) SO & \multirow{6}{*}{Slightly: \(\text{C}\leq 0.1\) and AP} & \multirow{6}{*}{Slightly: \(\text{WE}\in[0,0.1)\)} \\  & & & & \(0.1<\text{C}\leq 0.3\) and & Mildly: \(\text{WE}\in[0.1,0.4)\) \\ \cline{1-1} \cline{4-6}  & & & \(0.5\text{S}\cup\text{AP}\leq\text{S}_{0}\) & Moderately: \(\text{WE}\in[0.4,\) \\ \cline{1-1} \cline{4-6}  & & & Moderately: \(\text{0.3}<\text{C}\leq 0.5\) & 0.8) & \\ \cline{1-1} \cline{4-6}  & & & \(\text{and}\text{S}_{0}<\text{AP}\leq 2\text{S}_{0}\) & Severely: \(\text{WE}\in[0.8,1.0)\) & \\ \cline{1-1} \cline{4-6}  & & & Severely: \(\text{C}>0.5\) and AP \(>\) & & \\ \cline{1-1} \cline{4-6}  & & & \(2\text{S}_{0}\) & & \\ \hline \multirow{6}{*}{Method 2 [26]} & \multirow{6}{*}{TO, FO, SO, AE, SD, SK} & \multirow{6}{*}{RV, AV, MV} & C = 0.4 (TO \(\times\) FO \(\times\) SO) + 0.1 AE + 0.1 SD + 0.1 SK + 0.1 & \multirow{6}{*}{V} \\  & & & & RV + 0.1 AV + 0.1 MV & & \\ \cline{1-1} \cline{4-6}  & & & & \(\text{RV}\), AV, MV & Slightly: \(0\leq\text{C}<1\) & \\ \cline{1-1} \cline{4-6}  & & & & Mildly: \(1\leq\text{C}<4\) & & \\ \cline{1-1} \cline{4-6}  & & & & Moderately: \(4\leq\text{C}<7\) & & \\ \cline{1-1} \cline{4-6}  & & & & Severely: \(7\leq\text{C}\leq 10\) & & \\ \hline \multirow{6}{*}{Method 4 [27]} & \multirow{6}{*}{TO, FO, SO, AP} & \multirow{6}{*}{TR, SR, FR, ER} & C = \((TO\times FO\times SO)^{\frac{1}{3}}\) & \multirow{6}{*}{T = \(f(TR\bullet S\bullet F\bullet F\bullet ER)\)} \\  & & & & Slightly: \(0<\text{C}\leq 0.1\) or AP & & \\ \cline{1-1} \cline{4-6}  & & & \(\text{S}_{1}\text{S}_{0}\) & & Slightly: \(\text{T}\leq\text{S}_{0}\) & \\ \cline{1-1} \cline{4-6}  & & & Mildly: \(0.1<\text{C}\leq 0.4\) or & Mildly: \(\text{S}_{0}\leq\text{T}\leq\text{a}_{1}\text{S}_{0}\) & & \\ \cline{1-1} \cline{4-6}  & & & \(\text{b}_{1}\text{S}_{0}<\text{AP}\leq\text{b}_{2}\text{S}_{0}\) & Moderately: \(\text{a}_{1}\text{S}_{0}\leq\text{T}\leq\text{a}_{1}\) & & \\ \cline{1-1} \cline{4-6}  & & & & Moderately: \(0.4<\text{C}\leq 0.7\) & & \\ \cline{1-1} \cline{4-6}  & & & & or \(\text{b}_{2}\text{S}_{0}<\text{AP}\leq\text{b}_{3}\text{S}_{0}\) & Severely: \(\text{a}_{2}\text{S}_{0}\leq\text{T}\leq\text{a}_{3}\text{S}_{0}\) & & \\ \cline{1-1} \cline{4-6}  & & & & Severely: \(0.7<\text{C}\leq 1.0\) or & Work damage: \(\text{T}\geq\text{S}_{\text{max}}\) & \\ \cline{1-1} \cline{4-6}  & & & & \(\text{AP}\geq\text{b}_{3}\text{S}_{0}\) & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Typical comprehensive evaluation based on the basic four-domain method. Figure 3: The research design for the electromagnetic environmental effect evaluation is based on grey theory and AHP. adaptability of a certain type of equipment to reflect the electromagnetic environmental complexity. As a result, they built a comprehensive evaluation model through the weighting method in the same manner as [30]. Additionally, more and more attention is paid to the fusion research [32] of the interference signal characteristics and work efficiency of the equipment in an electromagnetic environment. [PERSON] et al. [33] evaluated the comprehensive electromagnetic environment's complexity from the perspective of different objects in that environment. Then, the basic evaluation indexes are determined according to each object. They also used the grey and AHP methods to assess the complexity of the electromagnetic environment, which actualized or realized the unification of qualitative and quantitative assessments. [PERSON] et al.