Figure4

Figure 4. The equivalent form of the set $$ \mathbf{D}^{(t)}_{\begin{matrix} b \lhd u\\ v \lhd 0 \end{matrix}}||\mathbf{D}^{(n-t)}_{\begin{matrix} u \lhd 0\\ a \lhd v \end{matrix}}(\alpha,\beta) $$.