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A\widetilde{T}P_1 =\dfrac{D_c}{p_mT_s+D_R}[0(c_m−c_s)p_mT_s−h_s(\dfrac{p_st^{2}_{s}}{p_m}−p_st^{2}_{s})−\widetilde{id}_s(T_R+p_st_s(\dfrac{1}{D_c}−\dfrac{1}{p_m})) \\ \begin{aligned} &-A_{s}+\left(c_{r}-c_{m}\right) p_{m} T_{s}-h_{m}\left(n p_{m} T_{s} T_{R}-\frac{n^{2}+n-2 r-2}{2} T_{R} D_{R}-\frac{p_{s}^{2} t_{s}^{2}}{2 p_{m}}\right) \\ &-A_{m}+\left(c_{r_{1}}-c_{r}\right) p_{m} T_{s}-\frac{h_{r}}{2}\left(\frac{p_{m}^{2} T_{s}^{2}}{D_{c}}-2 n p_{m} T_{s} T_{R}-(2 n+1) T_{R} D_{R}\right) \\ &\left.-\widetilde{i d}_{m}\left(\frac{p_{m} T_{m}-n D_{R}}{D_{c}}\right)+\frac{(n+1) c_{r_{1}} \widetilde{I}_{r e} D_{c} M^{2}}{2}-\widetilde{i d}_{r} T_{R}-A_{r}\right] \end{aligned}