• Proceedings of the Korean Society of Medical Physics Conference
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• 1999.11a
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• pp.238-239
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• 1999

• Journal of radiological science and technology
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• v.21 no.1
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• pp.35-39
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• 1998

We analyzed image factors to determine the characteristic factors that need for intelligent replenishment system of the auto film processor. We processed the serial 300 sheets of radiographic films of chest phantom without replenishment of developing and fixation replenisher. We took the digital data by using film digitizer which scaned the films and automatically summed up the pixel values of the films. We analyzed characteristic curves, average gradients and relative speeds of individual film using densitometer and step densitometry. We also evaluated the pH of developer, fixer, and washer fluid with digital pH meter. Fixer residual rate and washing effect were measured by densitometer using the reagent methods. There was no significant reduction of the digital density numbers of the serial films without replenishment of developer and fixer. The average gradients were gradually decreased by 0.02 and relative speeds were also gradually decreased by 6.96% relative to initial standard step-densitometric measurement. The pHs of developer and fixer were reflected the inactivation of each fluid. The fixer residual rates and washing effects after processing each 25 sheets of films were in the normal range. We suggest that the digital data are not reliable due to limitation of the hardware and software of the film digitizer. We conclude that average gradient and relative speed which mean the film's contrast and sensitivity respectively are reliable factors for determining the need for the replenishment of the auto film processor. We need more study of simpler equations and programming for more intelligent replenishment system of the auto film processor.

• Journal of The Korean Radiological Technologist Association
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• v.25 no.1
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• pp.33-34
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• 1999

As a result of execution of study through questionaries conerning the actual status of working being done by radiologises of the diagnostic radiation department, making 171 radioists who responded mon 200 radiogists City as of October 1998, as the subject

• Journal of The Korean Radiological Technologist Association
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• v.25 no.1
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• pp.264-274
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• 1999

As a result of execution of study through questionaires conerning the actual status of working being done by radiotechnologists of the diagnostic radiation department, making 171 radiotechnologists who responded among 200 radiotechnologists City as of Oct

• Journal of The Korean Radiological Technologist Association
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• v.28 no.1
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• pp.120-144
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• 2002

Purpose The quality assurance in a computed tomography gives a definition to be all the activity so as to optimize the performance of the device and keep an invariable quality of image, and it is to raise a high diagnostic efficiency to obtain a much info

• Journal of The Korean Radiological Technologist Association
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• v.28 no.1
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• pp.74-82
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• 2002

1. Purpose Presently, the service areas of those who we engaged in radiation works are being specialized. Thus, in this study, we propose a way for efficiently improving mutual relationship between the works of the radiation technicians(radiologists) and

• Imaging Science in Dentistry
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• v.34 no.1
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• pp.19-23
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• 2004

Purpose: To compare the diagnostic accuracy of Kodak Insight film with other intra-oral films in the detection of dental caries. Materials and Methods : Periapical radiographs of 99 extracted human teeth with sound proximal surfaces and interproximal artificial cavities were made on Kodak Ultra speed, Ektaspeed, Agfa Ektaspeed and Kodak Insight films and automatically processed. Six dentists examined the presence of dental caries using a five-point confidence rating scale and compared the diagnostic accuracy by ROC (Receiver Operating Characteristic) analysis and ANOVA test. Results: The sensitivity of Kodak Ultra speed, Ektaspeed, Agfa Ektaspeed and Insight film were 0.84, 0.77, 0.75 and 0.79 respectively. The specificity of Kodak Ultra speed, Ektaspeed, Agfa Ektaspeed and Insight film were 0.97. 0.95. 0.96 and 0.94 respectively. The mean ROC areas (Az) of Kodak Ultra speed, Ektaspeed, Agfa Ektaspeed and Insight film were 0.917, 0.910, 0.894, 0.909 respectively. There was no significant differences between Az of Insight film and other films (p = 0.178). Conclusion: Theses results suggested that Kodak Insight film have the comparative diagnostic accuracy of dental caries with Ultraspeed and Ektaspeed films.

• Korean Journal of Radiology
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• v.23 no.8
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• pp.777-784
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• 2022

• Journal of radiological science and technology
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• v.15 no.1
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• pp.99-105
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• 1992

Visual evaluation of rib shadow and lung marking during high voltage chest radiography. The Purpose of this study is to improvement of visual discrimination of pulmonary structures on the conventional chest radiogram. The author prepared an artificial lung using an acryl plate, 8 cm in thickness, which is nearly equivalent to human lung, and 0.6 cm thickness of an aluminum plate for an artificial rib, and 0.5 cm of an acryl plate as a pulmonary vessel as well. And they were used as objects for experimental radiograms. This study performed with gradual increasing densities of film bases in the sequences of densities of 0.6, 0.9, 1.1 and 1.3. We made two combinations of images after multiple and regular cuts, with width of 1 cm, of 4 radiograms at the above mentioned densities of film bases. One image consisted of alternative combination of radiograms taken at densities of 0.6 and 1.3, and the other did at 0.9 and 1.1. The latter image provided better visual perception of pulmonary structures than the former. Experimental radiograms were also taken with 60 kV and 120 kV respectively. After careful evaluation and comparison to images taken on varieties of different densities with combinations and kV, the author had a conclusion that it is advisable to use a high kV X-ray which makes rib shadow subtle, for better visual delineation of pulmonary structures behind ribcage, eventhough contrast of pulmonary structures are decreased at high kV radiogram.

• Journal of Yeungnam Medical Science
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• v.13 no.1
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• pp.134-140
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• 1996

Recently many studies have shown the usefulness of computed tomogram in diagnosing abdominal mass when clinical and conventional radiologic examinations fail to reveal the nature of abdominal mass or the cause of abdominal distension. To evaluate the usefulness of CT in diagnosing neuroblastoma, we retrospectively analyzed computed tomographic findings of 16 neuroblastoma patients, who pathologically proved in Yeungnam University Hospital from 1986 to 1995. The age range of the patients studied were from 8months to 18years. The most frequent sith of origin was adrenal gland and the next was retroperitioneum. The presenting symptoms were palpable mass, abdominal distension, and abdominal pain. The viewpoints of this analysis were turnoral calcifications, midline cross, shape, margin, internal structure, contrast enhancement patterns, major vessel involvement, and lymph node involvement. Characteristic CT findings were as follows: Fine dense curvillinear calcification within the tumor(56%), midline cross(50%), lobulation(75%), well-circumscribed margin(56%), cystic degeneration(56%), heterogeneous contrast enhancement(69%). encasement of major vessels such as aorta, IVC and celiac trunk(50%), and paraaortic lymphadenopathy(87%). We conclude that these CT findings were very common and could be helpful in diagnosting and differentiation neuroblastoma in infant and children.