 is defined as follows: <span class="math display">\[\begin{equation}
    \mu_{\triangle_{\downarrow}}(x_{jk}):=
    \begin{cases}
        \displaystyle\frac{x_{jk}-\mathrm{min}}{\mathrm{max}-\mathrm{min}},&amp;\mathrm{min}\leq x_{jk}\leq\mathrm{max}\\
        0,&amp;\mathrm{otherwise}
    \end{cases}
\end{equation}\]</span> where <span class="math inline">\(\mathrm{min}:= v_0:= v_1-\gamma\)</span>, <span class="math inline">\(\mathrm{max}:= v_p:= v_{p-1}+\gamma\)</span>, and <span class="math inline">\(\ga