918252.fig.0027a
(a) and are active
918252.fig.0027b
(b) and are active
918252.fig.0027c
(c) and are active. Note that the tiny uncovered region is located between and . For example, cannot be covered
918252.fig.0027d
(d) and are active
Figure 27: cannot be fully unit-disk covered by two opposite polar nodes from , even if all the nodes in and are active. The shaded regions indicate the uncovered regions.