
160
Wireless Ad Hoc and Sensor Networks
P(W
i
)=[(1 −
ω
1
)(1 −
ω
2
)···(1 −
ω
k
i
)(1 −
ω
i
)]
τ
≤ (1 −W )
τ
≤ (1 −min{
ω
∗
i
|v
i
∈
V,
ω
∗
i
> 0})
τ
≤ (e
−min{
ω
∗
i
|v
i
∈V,
ω
∗
i
>0}
)
τ
= e
−
7min{
ω
∗
i
|v
i
∈V,
ω
∗
i
>0}ln(n)
min{
ω
∗
i
|v
i
∈V,
ω
∗
i
>0}
≤ e
−7ln(n)
=
1
n
7
.
Thus, according to the Borel-Cantelli lemma, P(W
i
) ∼0, which implies that there
exists one independent node in the set N
1
(v
i
)
{v
i
} almost surely, i.e., it is almost
sure that the set M = {v
i
|
ω
i
= 1,0 ≤i ≤n}derived from Algorithm 9 is a DS. Then,
it is reasonable that we consider M is a DS of G in the following.
2
2
Based on Lemma 7.1 and Lemma 7.2, the following theorem can be obtained.
Theorem 7.1
The set M = {v
i
|
ω
i
= 1,0 ≤ i ≤ n},where
ω
i
is