• Progress in Medical Physics
• /
• v.18 no.2
• /
• pp.98-106
• /
• 2007

In June 2005, Yonsei University Medical Center, Severance Hospital upgraded a full-PACS system by adding twenty (5 mega pixels) Totoku ME511L flat panel LCD display devices for diagnostic interpretation purposes. Here we report upon the quantitative (or visual) acceptance testing of the twenty Totoku ME511L display devices for reflection, luminance response, luminance spatial dependency, resolution, noise, veiling glare, and display chromaticity based on AAPM TG 18 report. The tools used in the tests included a telescopic photometer, which was used as a colorimeter, illuminance meter, light sources for reflection assessment, light-blocking devices, and digital TG18 test patterns. For selected 8 flat panel displays, mean diffuse reflection coefficient ($R_d$) was $0.019{\pm}0.02sr^{-1}$. In the luminance response test, luminance ratio (LR), maximum luminance difference ($L_{max}$), and deviation of contrast response were $550{\pm}100,\;2.0{\pm}1.9%\;and\;5.8{\pm}1.8%$, respectively. In the luminance uniformity test, maximum luminance deviation was $14.3{\pm}5.5%$ for the 10% luminance of the TG18-UNL10 test pattern. In the resolution test with luminance measurement method, percent luminance (${\Dalta}L$) at the center was $0.94{\pm}0.64%$. In all cases of noise testing, rectangular target In every square in the three quadrants was visible and all 15 targets except the smallest one in the every corner pattern and the center pattern. The glare ratio (GR) was $12,346{\pm}1,995$. The color uniformity, (u',v'), was $0.0025{\pm}0.0008$. Also, the research results of qualify control guideline of primary disply devices suitable for domestic circumstance are presented All test results are in-line with the criteria recommended by AAPM TG18 report and are thus fully acceptable for diagnostic image interpretation. As a result, the acceptance testing schedule described provides not only an acceptance standard but also guidelines for quality control, optimized viewing conditions, and a means for determining the upgrading time of LCD display devices for diagnostic interpretation.

• Korean Journal of Heritage: History & Science
• /
• v.55 no.3
• /
• pp.120-129
• /
• 2022

The purpose of this study is to analyze the chemical composition of smalt pigments used in 10 large Buddhist paintings in the Joseon Dynasty using energy dispersive X-ray spectroscopy, and to clarify the material and characteristics by observing morphological characteristics using polarized light microscopy and a scanning electron microscope. Through chemical composition analysis, the smalt of all 10 large Buddhist paintings is judged to be potash glass using SiO₂ as a former and K₂O as a flux. In addition to the components related to cobalt ore used as a colorant, the paintings were found to contain high levels of As₂O₃, BaO, and PbO. The smalt particles did not have specific forms, and were blue in color, with various chromaticity. In some particles, conchoidal fracture, spherical bubbles, and impurities were observed. Through backscattered electron images, it was found that the smalt from paintings produced in the early 18th century AD had a high level of As, but the smalt from paintings produced from the mid-18th century AD onwards exhibited various contrast differences from particle to particle, and there was smalt with high levels of As, Ba, and Pb. Through the above results, the large Buddhist paintings in the Joseon Dynasty are divided into three smalt types. Type A is a type with high As₂O₃, type B is a type with high BaO, and type C is a type with high PbO. Looking at the three types of smalt pigments by the period of production, although some in-between periods were not detected, type A was confirmed to have been used from 1705 to 1808, while type B and type C were shown to have appeared in 1750 and used until 1808. This reveals that only one type of smalt was used until the early 18th century AD, and from the middle of the 18th century AD, several types of smalt were mixed and used in one large Buddhist painting. Studies such as this research are expected to provide insights into the characteristics of the smalt pigments used to produce large Buddhist paintings at the time.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.18 no.1
• /
• pp.79-91
• /
• 2016

Quality factors which characterize 11 kinds of farm-manufactured apple Jangachi and commercial Jangachi, have been studied in order to provide a guideline to improve the quality and marketing strategy of farm-manufactured pickled apples. Moisture content ranged from 74% to 84% and 81% to 91% in Doenjang Jangachi and vinegar Jangachi, respectively; 38% to 64% in Kochujang Jangachi; 57% to 64% in radish Kochujang Jangachi. Moisture content was 89% in Doenjang Jangachi. Even though moisture content of apple Kochujang Jangachi indicated 48% which is lower than that of radish Jangachi, it was higher than that of a persimmon pickled in Kochujang (38%) and that of Japanese apricot Jangachi (49%). pH and titratable acidity, two indicators used to determine the appropriate ripening period of Jangachi, were pH 3.4~5.6, 0.03~0.14%, respectively. The pH ranged from 5.2 to 5.6 in radish Jangachi; 3.4 to 4.1 in Cucumber Jangachi. pH of persimmon Jangachi, Japanese apricot Jangachi and apple Jangachi showed 4.1, 3.5 and 4.1, respectively. Compared with the pH of traditional Jangachi (3.03~5.36), pH of all of the above Jangachi fall into an appropriate range. The brix of apple Jangachi (30%) was 12% to 18% higher than that of Kochujang radish Jangachi, but it was relatively lower than that of persimmon Jangachi (39%) and that of Japanese apricot Jangachi (49%). Salinity of Jangachi varied depending on which marinating material was used. Salinity in the descending order according to each marinating material demonstrated Kanjang (6% to 13%), Doenjang (7%), Kochujang (3% to 4%). Salinity of apple Jangachi was 3.28% which was relatively lower than that of commercial Jangachi which used either Kanjang or Doenjang as its marinating material. Chromaticity test shows that the brightness value of apple Jangachi (54.70) was similar to that of cucumber Jangachi (50.86, 56.02); the redness value and yellowness of apple Jangachi (16.21 and 26.78) were higher than the redness value (7.27 to 11.23) and the yellowness value (10.62 to 14.69) of radish Kochujang Jangachi. Sensory Characteristics value of apple Jangachi, along with radish and cucumber Jangachi in its color, odor and taste (7.00, 7.50, 7.00, respectively) placed high on the list implying higher preference. However, overall preference value of apple Jangachi was 6.83 which was lower than that of Japanese apricot Jangachi or that of radish Jangachi. The result can be explained by the tendency of people preferring crispy Jangachi and points out that the texture of apple Jangachi needs to be improved to gain popularity. Furthermore, for increased sales of apple Jangachi as a niche product, more rigorous market testing is required.