X
1
= X
2
X
1
= −X
2
u = (x
1
−x
2
)/2, v = (y
1
−y
2
)/2, w = (z
1
−z
2
)/2, u
1
= (x
1
+x
2
)/2, v
1
=
(y
1
+ y
2
)/2, w
1
= (z
1
+ z
2
)/2
˙u = α [v − u − c(u)] ,
˙v = u − v + w −2γ [u − v + w] ,
˙w = −βv,
˙u
1
= α [v
1
− u
1
− c(u
1
)] ,
˙v
1
= u
1
− v
1
+ w
1
,
˙w
1
= −βv
1
,
c(u) = [h(x
1
) − h(x
2
)] /2, c(u
1
) = [h(x
1
) + h(x
2
)] /2
X
1
= X
2
X
1
= −X
2
X
1
=
X
2
F (u) =
ru
r u = v = w = 0
X
1
= X
2