• Korean Journal of Digital Imaging in Medicine
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• v.10 no.1
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• pp.35-40
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• 2008

I.objective The composition method with acquiring 2${\sim}$5 image not only lack perfection in compensating the geometrical distortion but could also cause inaccurate connection problem of compensating the geometrical distortion but could also cause inaccurate connection problem of continuing bone structure due to the enlargement ratio difference of ruller and bone, density difference in image composition process. This paper studies those mentioned problems through the experiments. II. Object and method Experiment 1 After attaching 3 step wedge(Pb) on detector and 2 ruller on upper, lower part of the step wedge, we have exposed them to create density difference between 1st image and 2nd image, then examined if there were any errors. Experiment 2 1st 100cm ruller was attached on the center of detector, and by escalating the distance between 2nd 100cm ruller and detector 5cm, 10cm, 15cm respectively, we investigated if there any errors caused by enlargement ratio. Experiment 3 The ruller was placed on detector, a joint photographing was performed through spot photographing after fully operating the electric field photographing to include hip joint ${\sim}$ ankle joint part and we have compared the values from two methods. III. Result : A horizontal axis error was caused when photopraphing is not poerated in equal density since the image shifted horizontally in accordance with the difference of Pb step wedge 1 due to the density difference, as the result of Epperiment 1.

• Journal of Korean Ophthalmic Optics Society
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• v.3 no.1
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• pp.209-216
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• 1998

The purpose of this study was to compare the right and left eye size, distance between two eyes, interpupillary distance on growth stage aging changes in Korean. The author divided into 5 groups according to subject's age(group A : 7~12 years, group B : 13~15 years, group C : 16~18 years, group D : 19~24 years, group E : 25~30 years). The high values of inter outer canthal distance(T) and distance between two eyes(G) were 94.30 mm, 36.66 mm at group B respectively. The ratio of identical eye size was about 10.0% in A, B, C group but 22.7% in E group. P[T-(right eye size + left eye size) / 2] was wider than IPD. Data showed that the difference was 5.72 mm in group B and 1.13 mm in group E. The reason for this is that the pupils are displaced nasally from the center of the limbal ring. This has significant meaning in ophthalmic procedures.