t
i
m
e
0
.
0
0
1
r
e
g
i
o
n
l
e
n
g
t
h
L
1
s
o
u
r
c
e
p
o
i
n
t
x
o
0
.
2
b
o
u
n
d
a
r
y
c
o
e
f
f
i
c
i
e
n
t
s
b
1
a
t
x
=
0
0
b
2
a
t
x
=
L
2
0
0
0