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Computerized tomography (CT), ultrasound sector scan and X-ray
images are extensively used in medical diagnoses and industrial
non-destructive test for positioning structures inside objects.
However, there are some defects in the use of computerized
tomography, including the high cost of the CT equipment and the
over-exposure of radiation on patients. Though there is no
radiation in using ultrasound sector scan, but it can not
provide precise positioning. In contrary, using X-ray images in
determining positThis research attempts to proceed the 3-D
position of lineear features using X-ray images taken at
multiple angles. The space intersection method was applied to
determine the spatial positions of the central lines of the
linear features. Meanwhile, sources of errors in 3-D positioning
using X-ray images were analyzed for reference in positioning of
blood vessels, fissure, defects in material and so on. Empirical
results of this research show that the precision of X-ray image
positioning reaches the same level as that of positioning using
precise theodolite. In the results, measured central lines of
the features show some distortions. The magnitude of distortion
highly depends on the angle between the X-ray films, the angle
between the object and X-ray film, the quality of the digitized
X-ray image, and the density and distribution of measured
points.
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