Biomedical Engineering Reference
In-Depth Information
B
B
(
a
)
A
(
b
)
A
(
c
)
B
0.0
1.5
1.5
C
C
C
0.5
1.0
1.0
D
D
D
-1.0
-1.0
E
E
-1.0
B
B
(
d
)
(
f
)
A
B
A
(
e
)
A
C
C
C
D
D
D
E
E
E
Fig. 3.47.
An example of drawing a contour map.
a
A set of data at five observation
points was given.
b
Triangular meshes were produced.
c
A segment of a contour
was determined on one of the triangular meshes.
d
A contour was formed after
examining all the triangles.
e
The same procedure was repeated, with different
values of the contours.
f
The whole contour was obtained
(
a
)
(
b
)
Fig. 3.48.
A field contour map with an ideal single current dipole.
a
An example
of a contour map with a dipole-like pattern. Black lines represent an upward field.
Gray lines represent a downward field.
b
The estimation of a magnetic source. The
arrow represents the estimated current dipole
After examining the contour for all the triangles, a whole connected con-
tour is represented. Furthermore, a whole contour map is obtained by repea-
tingthesameprocedurewithdifferentvaluesforthecontours.
In Fig. 3.47, an example of making a contour map from a set of data
at five observation points is shown. The contour map in the figure is very
angular because only a few observation points are used for simplicity. More
observation points located at narrower intervals can provide a smoother con-
