( ,1978 )( ,1978 )( ,1978 )( ,1978 )
44
4
4
433
3
3
4
2 3
3
2
4
12
111
0
1
2
3
4
5
(S40 )
0
10
20
30
40
50
60
70
80
90
0
1
2
3
4
5
6
7
0
5
10
15
20
25
30
cm/s
Vg/Vw 1/3.316cm/s > 12.9cm/s
54cm/s > 42.3cm/s
30mm
D
°
[ No.2][ No.1]