• Journal of the Korean Professional Engineers Association
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• v.28 no.5
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• pp.12-19
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• 1995

Korean fresh elephant -foot (Amorphophalus Konjak K. Koch) and its powder were analyzed and compared with foreign samples for the purpose of investigating the physico -chemical characteristics of Korean konjak. The Korean fresh konjak contains 80.64% of moisture and most of the solid component comprises sugar, protein and trace of fat and fibre. The mannan content of Korean konjak powder is far smaller than those of Japanese and Chinese konjak powder. The analysis of the korean konjak protein tells that 45% of glutamic acid, aspartic acid and argi-nine is included other remaining amino acid is larger with the order of valine, serine, leucine, and gly-cine. The Korean konjak contains a moderate amount of K component and other inorganic component increases with the order of P Na and Ca. The yield of konjak refined powder from dried chip was 61% and 51.5% of korean and chinese re-spectively. The whiteness degree of chinese konjak powder was slightly higher than that of korean product but the difference could not be recognized by the naked eye.

• Food Science and Preservation
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• v.22 no.4
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• pp.498-504
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• 2015

The purpose of the present study is to provide preliminary data for turning sweetpotato leaves into dehydrated vegetables. To achieve this goal, we have gone through the process of hot-air drying the leaves of sweetpotato that are usually thrown away and examined the drying speed and rehydration resilience, then made a comparative analysis of the general ingredients, lutein, $\beta$-carotene and chromaticity. The drying speed reached the peak at a temperature of $70^{\circ}C$. As for other general ingredients, there was no significant difference according to temperature. The content of lutein, which is a functional ingredient, was large in Shinmi with $171.59{\mu}g/g$ at a temperature of $40^{\circ}C$; small in Hayanmi with $73.75{\mu}g/g$ at a temperature of $70^{\circ}C$. The content of $\beta$-carotene was large in Shinmi with $379.59{\mu}g/g$ at a temperature of $40^{\circ}C$; small in Hayanmi with $170.78{\mu}g/g$ at a temperature of $70^{\circ}C$. The content of functional materials was the largest at a temperature of $40^{\circ}C$, and decreased in the order of temperatures at $50^{\circ}C$, $60^{\circ}C$, and $70^{\circ}C$. As for rehydration stability, rehydration rate in both Shinmi and Hayanmi was the highest at a temperature of $40^{\circ}C$ with 233.93% and 223.47% respectively. To summarize, the quality of dried sweet potato leaf was more affected by temperature than by drying time, and low temperature drying resulted in better product value.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.2
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• pp.168-179
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• 2002

The purpose of this study was to find a method for improving the children's behavior during dental treatment in relation with dentist's attire. For this study 150 children, visiting a dental clinic, were asked to participate in a survey on the attire of the dentist. The results of the survey were as follows: 1. In the survey for the preference between gown and ordinary clothes according to sex(P<0.05), age(P<0.05), residence (P<0.05) and number of visits(P<0.05), there was more preference for gown(65.3%). 2. The preference for the type of gown and attire under the gown was a long gown and white shirt (30.7%), followed by a suit-like gown (18.7%) and white shirt, and long gown and polo shirt(17.3%). 3. The preference for the color of gown was white(34.7%), followed by pink (18.7%), green(18.0%), blue(15.3%) and yellow(13.3%). 4. The preference for the pattern on the gown was cartoon characters(49.3%), followed by hospital logo(28.7%) and no pattern(14.7%). 5. The preference for ordinary clothes of female dentists was polo shirt(37.3%), followed by striped shirt(28.7%), round T-shirt(18.7%), and everyday Korean traditional dress(15.3%). 6. The preference for ordinary clothes of male dentists was pattern necktie and no pattern Y-shirt(28.0%), followed by no pattern necktie and Y-shirt(21.3%) or pattern shirt with no necktie, and no pattern Y-shirt with no necktie(14.7%). 7. The preference on the protective equipment worn was mask and glove(28.7%), followed by no protective equipment(26.7%), mask, glove and protective glasses(22.7%) at)d only mask(22.0%). Based on the above results, it seems that parting with the traditional white gown and wearing multi-color and pattern attire will provide psychological stability and help improve children's behavior during treatment.

• Restorative Dentistry and Endodontics
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• v.32 no.2
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• pp.138-150
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• 2007

The purpose of this study was to evaluate the difference of surface roughness of composite resin according to composite resin type, polishing methods, and use of resin sealant. Two hundred rectangular specimens, sized $8{\times}3{\times}2mm$, were made of Micro-new (Bisco, Inc., Schaumburg, IL, U.S.A) and Filtek Supreme (3M ESPE Dental Products, St. Paul, MN, U.S.A.), and divided into two groups; Micronew-M group, Filtek Supreme-S group. Specimens for each composite group were subdivided into five groups by finishing and polishing instruments used; M1 & S1(polyester strip), M2 & S2 (Sof-Lex disc), M3 & S3 (Enhance disc and polishing paste), M4 & S4(Astropol) and M5 & S5 (finishing bur), Polished groups were added letter B after the application of resin surface sealant (Biscover), eg, M1B and S1B. After specimens were stored with distilled water for 24hr, average surface roughness (Ra) was taken using a surface roughness tester. Representative specimens of each group were examined by FE-SEM (S-4700: Hitachi High Technologies Co., Tokyo, Japan). The data were analysed using paired t-test, ANOVA and Duncan's tests at the 0.05 probability level. The results of this study were as follows ; 1. The lowest Ra was achieved in all groups using polyester strip and the highest Ra was achieved in M5, S5 and M5B groups using finishing bur. On FE-SEM, M1 and S1 groups provided the smoothest surfaces, M5 and S5 groups were presented the roughest surfaces and voids by debonding of filler on the polished specimens. 2. There was no significant difference in Ra between Micronew and Filtek Supreme before the application of resin sealant, but Micronew was smoother than Filek Supreme after the application of resin sealant. 3. There was significant corelation between Ra of type of composite resin and polishing methods before the application of resin sealant (p=0.000), but no significant interaction between them after the application of resin sealant. On FE-SEM, most of composite resin surfaces were smooth after the application of resin sealant on the polished specimens. 4. Compared with before and after the application of resin sealant in group treated in the same composite and polishing methods, Ra of M4B and M5B was statistically lower than that of M4 and M5, and S5B was lower than that of S5, respectively (p<0.05). In conclusion, surface roughness by polishing instruments was different according to type of composite resin. Overall, polyester strip produced the smoothest surface, but finishing bur produced the roughest surface. Application of resin sealant provided the smooth surfaces in specimens polished with Enhance, Astropol and finishing bur, but not provided them in specimens polished with Sof-Lex disc.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.4
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• pp.277-284
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• 1998

Random amplified polymorphic DNA (RAPD) analysis was used to detect the genetic diversity of soybean (Glycine max (L.) Merr.) varieties and field bean (Glycine soza Sieb. and Zucc.) Five soybean varieties and one field bean were analysed with random primers using the polymerase chain reaction (PCR). Nine primers of a total twenty random primer were selected to amplify DNA segments. A total of 74 PCR products were amplified and 67.6% of which were polymorphic. The size of DNA molecule is ranged 0.13~2.0Kb and typically generated four to eight major bands. Specific genetic marker were revealed in primer sequence 5'-CAG GCC CIT C-3', 5'-TGC TCT GCC C-3' and 5'-GTC CAC ACG G-3', respectively. Genetic similarity between each of the varieties were calculated from the pair-wise comparisons of amplification products and a dendrogram was constructed by an unweighted pair-group method with arithmethical means (UPGMA). The results indicate that intervarietal relationships of soybean have a narrow genetic base and between the varieties, Hwanggum-kong and Seckryang-bootkong is more closely related than the rest of varieties, and field bean is related quite distant.

• Archives of design research
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• v.15 no.4
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• pp.263-274
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• 2002

This study aims to analyze the image of long-span structures. For the intention, it analyzes the relationship between images and physical attributions of elements such as materials, stresses, configurations, compositions and shapes of structures. The image of structures can represent following 5 factors; friendly-unfriendly, strong-weak, dynamic-calm, superior-inferior, and regular-irregular. The friendly-unfriendly in the image of structure mostly determines on a finished material and partly with a structural shape. The strong-weak in the image of structure determines on configuration of the structural members. The dynamic-calm in the image of structure determines on the structural shape. Hence the structure has dynamic forms when it seems to be open and sharp, namely when it receives the flow of forces in the structural shape, and it has a (-) gauss curved rate or an diagonal appearance. The superior-inferior in the image of structure determines on composition of structural elements. The structure seems to be superior is contributed not simply to support load but positively to create design as a tectonic element. From now on, this study can provide the useful information on the long-span structure design through the more appropriate analysis of the image.

• Journal of Conservation Science
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• v.35 no.5
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• pp.518-527
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• 2019

This investion studies the manufacturing techniques of chimi(ridge-end roof tiles based on the) fragments excavated from the Wonju Beopcheonsa temple site(Historic site No. 466) and aids in the conservation of the fragments. The results of the investigation are categorized into the production of the body parts, the wing and the feather attachment, the production of the decorative parts, the scratches in the upper and lower part, the perforations connecting the upper and lower parts, and the formative features(bending phenomenon). The procedures in the conservation treatment of the chimi was performed in a sequential order beginning with a preliminary examination, followed by the removal of foreign substances, coating, joining and restoration, and color retouching. A three-dimensional scanning data was employed to restore the missing parts after adhesion to determine the location, size, and angle of the original shape. The restored chimi measures 118 cm in height and weighs 121 kg, which makes it the fifth largest in size among any chimi(including restored) in Korea. We expect that the pointed feathers will make the chimi from the Beopcheonsa temple site a rare reference as no specimens with these features have been found in Korea until now.

• Journal of the Korean Chemical Society
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• v.38 no.5
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• pp.351-358
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• 1994

The spectrophotometric determination of trace selenium(Ⅳ) using its catalytic reaction has been studied in aqueous solutions. The catalytic reaction of phenylhydrazine hydrochloride with selenium(Ⅳ) in an acidic aqueous medium produces benzenediazonium ion which will be converted into a red-coloured azo dye by coupling with H-acid(8-amino-1-naphtol-3,6-disulfonic acid disodium salt). For the reaction, the experimental conditions such as amounts of the reagents and pH of the sample solutions were optimized. After 15 ml of the sample solution was treated with 1 ml of 0.1 M EDTA solution to mask $Fe^{3+}$, etc., 1 ml of 0.06 M phenylhydrazine hydrochloride, 1 ml of 0.02 M H-acid, and 3 ml of 0.3 M-$KClO_3$ were added into the solution, sequentially. The solution was adjusted to pH 1.4 with HCl. After it was heated in a steam bath for 30 minutes, the solution was cooled down to a room temperature and then diluted to 25 ml with deionized distilled water. A blank solution for the absorbance measurement was prepared from the deionized water. The absorbance was measured at 527 nm. Using the above procedure, the trace amount of selenium was determined in natural waters such as tap, river and pond waters by a standard curve method and recoveries of Se spiked to samples were also obtained. From the recoveries of 104 to 111%, it could be concluded that this method was applicable to the quantitative determination of ng/ml level of selenium in natural waters.

• Economic and Environmental Geology
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• v.53 no.1
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• pp.87-98
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• 2020

The bird track fossil site in Haman Formation is divided into seven sedimental layers by the sedimentary structures, lithofacies and sequences. The bird tracks top on the highest layer, which includes ripple marks and suncracks. The layer has lithofacies with reddish grey siltstone and dark grey mudstone, alternately. As an analysis for the same rocks of the fossil site, physical properties show on mean values for 0.62% of absorption rate, 1.64% of porosity and 2.63 of specific gravity. Rock-forming minerals composed mainly of plagioclase, quartz, calcite, chlorite and mica. Meanwhile, we executed an experiments based on the petrography and weatherings to find a proper consolidants. In the experiments, the OH 100 reagent proved stable aspect and the lowest transition rate in terms of weight and chromaticity. Also, it showed the highest increase in ultrasonic velocity, improving the physical properties of the rocks. In the case of applying the OH 100 with antihygro, an swelling inhibitors on the sedimentary rocks, the chromaticity indicated an stable transition aspect. When it comes to the physical properties, the antihygro also decreases the porosity effectively. Thus, the most proper method for the fossil site of Haman Formation is to apply antihygro and OH 100 reagents since the rocks includes clay minerals that show swelling characteristics. However, this result is deduced from an indoor application experiments, leaving the necessity of verification how these reagents would affect the bird tracks site under the field condition.

• Korean journal of food and cookery science
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• v.29 no.6
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• pp.691-697
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• 2013

This study determines the processing suitability of pumpkin powder by assessing, the physicochemical properties of pumpkin powder subjected to different treatments: steaming, freezing and roasting. Pumpkin powder containing 13.61-16.05% moisture, 39.40-9.53% protein, 1.35-1.43% lipid, 0.26-0.50% ash, 5.01-5.65% yield, and 9.40-10.50 mg% sugar was used. In terms of color values, the L-value of control, a-value of the steamed sample, and b-value of the roasted sample waere the highest. The steamed sampled had the highest DPPH radical-scavenging activity. Reduction in sugar concentration varied significantly by treatments conditions (p < 0.05). Carotenoid concentration was the highest in control (19.75 mg%), followed by steamed sample (17.91 mg%), frozen sample (15.17 mg%), and the roasted sample (14.04 mg%). On the basis of these results, steamed pumpkin powder was identified as the most suited for instant processing.