• Korean Journal of Remote Sensing
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• v.39 no.6_2
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• pp.1605-1613
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• 2023

The physical properties of the ocean interior are determined by temperature and salinity. To observe them, we rely on satellite observations for broad regions of oceans. However, the satellite for salinity measurement, Soil Moisture Active Passive (SMAP), has low temporal and spatial resolutions; thus, more is needed to resolve the fast-changing coastal environment. To overcome these limitations, the algorithm to use the Geostationary Ocean Color Imager-II (GOCI-II) of the Geo-Kompsat-2B (GK-2B) was developed as the inputs for a Multi-layer Perceptron Neural Network (MPNN). The result shows that coefficient of determination (R²), root mean square error (RMSE), and relative root mean square error (RRMSE) between GOCI-II based sea surface salinity (SSS) (GOCI-II SSS) and SMAP was 0.94, 0.58 psu, and 1.87%, respectively. Furthermore, the spatial variation of GOCI-II SSS was also very uniform, with over 0.8 of R² and less than 1 psu of RMSE. In addition, GOCI-II SSS was also compared with SSS of Ieodo Ocean Research Station (I-ORS), suggesting that the result was slightly low, which was further analyzed for the following reasons. We further illustrated the valuable information of high spatial and temporal variation of GOCI-II SSS to analyze SSS variation by the 11th typhoon, Hinnamnor, in 2022. We used the mean and standard deviation (STD) of one day of GOCI-II SSS, revealing the high spatial and temporal changes. Thus, this study will shed light on the research for monitoring the highly changing marine environment.

• The Korean Journal of Food And Nutrition
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• v.19 no.3
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• pp.279-287
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• 2006

This study was carried out to investigate the influences of modified starches on suppression of retrogradation in Korean rice cake for their optimization, Garaeduk. Based upon studying Avrami equation, the Avrami exponent n value of all the experiment samples was found to be 1.03 ${\sim}$ 1.37 in the influence of modified starches on retrogradation of the rice cake. This means that the retrogradation of the Korean rice cake occurred instantly after the crystallization of starch particles in the Korean rice cake formulated by modified starches. The highest Avrami exponent n value was indicated in the control sample. The rate constant k of retrogradation in the Korean rice cake formulated by modified starches showed comparatively low and appeared to be the lowest in the Korean rice cake formulated by SHPP. This tendency was shown well in the time constant(1/k) of retrogradation velocity. According to the DSC analysis, the onset temperature of gelatinization in thermal characteristics showed somewhat high in case of addition of modified starch into the Korean rice cake on storage time and the SHPP was slowly gone up. In peak temperature of gelatinization in thermal characteristics of the DSC analysis, SSOS and ASA were increased a little in comparison with the control. The control was comparatively high increase. Melting enthalphy of all samples added with modified starches (SSOS: 21.1${\rightarrow}$23.7${\rightarrow}$24.1, ASA: 21.1${\rightarrow}$24.8${\rightarrow}$25.4) appeared to be lower than that of the Korean rice cake without modified starches(21.2${\rightarrow}$26.1${\rightarrow}$27.1). The Korean rice cake added with SHPP was shown to be the lowest in the increasing rate of melting enthalpy(20.9${\rightarrow}$21.4${\rightarrow}$22.1). Heat spreadability of all the samples in Martin melting diameter was revealed to be good in order of control, ASA, SSOS, SHPP and especially the Korean rice cake added with SHPP was shown to be the best in heat spreadability. In color, sensory examination and textural characteristic of the Korean rice cake added with modified starches, the L$^*$value was not changed practically with the storage time and seemed to be stable. The a$^*$ value of the samples was followed by control(2.21${\rightarrow}$5.34: 141.6%), ASA (2.01${\rightarrow}$4.22: 110.0%), SSOS (2.78${\rightarrow}$4.87: 75.2%) and SHPP (2.12${\rightarrow}$3.40: 60.4%) in order of color change. Also the b$^*$ value of the samples was followed by control(4.32${\rightarrow}$6.35: 47.0%), ASA (4.66${\rightarrow}$5.73: 23.0%), SSOS (4.90${\rightarrow}$5.89: 20.2%) and SHPP (4.89${\rightarrow}$5.12: 4.7%) and there was the least (or no) color change with the SHPP. Textural characteristics of samples was shown to be the highest in case of modified starch addition and especially SHPP appeared to be the best in texture.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.1
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• pp.1-11
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• 2008

Statement of problem: Over the past decade, increased demand for esthetically pleasing restorations has led to the development of all-ceramic systems. Recent reports suggest that the all-ceramic crowns have excellent physical properties, wear resistance, and color stability. In addition, numerous ceramics have excellent biocompatibility, a natural appearance, and improved physical bonding with resin composite luting agents. However, the brittle nature of ceramics has been a major factor in their restriction for universal usage. Functional occlusal loading can generate stress in the luting agent, and the stress distribution may be affected by the marginal geometry at the finish line. Tooth preparation for fixed prosthodontics requires a decision regarding the marginal configuration. The design dictates the shape and bulk of the all ceramic crowns and influences the fit at the margin. Purpose: The purpose of this study was to evaluate the stress distribution within marginal configurations of all- ceramic crowns (90-degree shoulder, 110-degree shoulder, 135-degree shoulder). Material and methods: The force is applied from a direction of 45 degrees to the vertical tooth axis. Three-dimensional finite element analysis was selected to determine stress levels and distributions. Results and conclusion: The result of stress level for the shoulder marginal configuration was more effective on stress distribution at 135-degree shoulder margin. But the stresses concentrated around at 135-degree shoulder margin. The stress decreased apically at the surface between cements and alumina core, and increased apically at the surface between alumina core and veneering porcelain.

• Korean Journal of Heritage: History & Science
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• v.48 no.2
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• pp.142-157
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• 2015

This study examines how traditional knowledge functions in the specific techniques to make pottery in terms of the traditional knowledge on the pottery techniques of Onggi potters. It focuses on how traditional pottery manufacturing skills are categorized and what aspects are observed with regard to the techniques. The pottery manufacturing process is divided into the preparation step of raw material, the molding step of pottery, and the final plasticity step. Each step involves unique traditional knowledge. The preparation step mainly comprises the knowledge on different kinds of mud. The knowledge is about the colors and properties of mud, the information on the regional distribution of quality mud, and the techniques to optimize mud for pottery manufacturing. The molding step mainly involves the structure and shape of spinning wheels, the techniques to accumulate mud, ways to use different kinds of tools, the techniques to dry processed pottery. The plasticity step involves the knowledge on kilns and the scheme to build kilns, the skills to stack pottery inside of the kilns, the knowledge on firewood and efficient ways of wood burning, the discrimination of different kinds of fire and the techniques to stoke the kilns. These different kinds of knowledge may be roughly divided into three categories : the preparation of raw material, molding, and plasticity. They are closely connected with one another, which is because it becomes difficult to manufacture quality pottery even with only one incorrect factor. The contents of knowledge involved in the manufacturing process of pottery focused are mainly about raw material, color, shape, distribution aspect, fusion point, durability, physical property, etc, which are all about science. They are rather obtained through the experimental learning process of apprenticeship, not through the official education. It is not easy to categorize the knowledge involved. Most of the knowledge can be understood in the category of ethnoscience. In terms of the UNESCO world heritage of intangible cultural assets, the knowledge is mainly about 'the knowledge on nature and universe'. Unique knowledge and skills are, however, identified in the molding step. They can be referred to 'body techniques', which unify the physical stance of potters, tools they employ, and the conceived pottery. Potters themselves find it difficult to articulate the knowledge. In case stated, it cannot be easily understood without the experience and knowledge on the field. From the preparation of raw material to the complete products, the techniques and traditional knowledge involved in the process of manufacturing pottery are closely connected, employing numerous categories and levels. Such an aspect can be referred to as a 'techniques chain'. Here the techniques mean not only the scientific techniques but also, in addition to the skills, the knowledge of various techniques and levels including habitual, unconscious behaviors of potters.

• Korean Journal of Poultry Science
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• v.36 no.2
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• pp.149-155
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• 2009

The present study was conducted to compare the carcass yields and meat characteristics of three types of commercial male chicks White mini broilers, Ross broilers and Hy-Line brown chicks under the identical feeding condition. One-hundred 1-d chicks of each type were randomly placed into four pens per group (25 chicks per pen) and fed corn-soybean meal based commercial diets for 35d, 18d or 49d, respectively. At the end of the feeding trial, the birds were sacrificed and subjected to carcass measurements. The dressing percentages of White mini broilers and Ross broilers were significantly higher (P<0.05) than that of Hy-Line brown cockerels. The rate of breast meat of Hy-Line brown cockerels was significantly lower (P<0.05) than those of White mini broilers and Ross broilers. However, Hy-Line brown cockerels showed higher (P<0.05) leg meats than the others. There were no significant differences in serum total cholesterol and the activities of glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase among the groups. The breast meats of White mini broilers presented highest lightness value. The yellowness of breast and redness of leg meats of White mini broilers and Ross broilers were significantly higher (P<0.05) than those of Hy-Line brown cockerels. There were no significant differences in the SOD-like activity and change of pH in edible meats among the groups. The meat color in White mini broilers was significantly higher than that of Hy-Line brown cockerels. No significant differences were observed in term of flavor, tenderness and overall acceptability. In conclusion, the physico-chemical properties and sensory characteristics of edible meats were not greatly affected by genotype if they were similar body weights and kept under the identical feeding condition. But the Hy-Line brown cockerels were less desirable as a meat-type strain due to lower carcass yields and inferior growth and feed conversion ratio.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.112-118
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• 1978

Four domestic frying oils (soybean, corn, rapeseed and rice bran oil) were studied on their changing properties according to thermal oxidation by means of chemical analysis of their compositions and measurements of various physical and chemical properties. The content of linoleic acid which is an essential unsaturated fatty acid and the total amount of unsaturated fatty acids were highest in soybean oil (53.2% and 80.3% respectively) among the unheated frying oils and the degree of its thermal degradation was lowest during the continuous heating period for 48 hours at $180^{\circ}C$. However in general, the contents of unsaturated fatty acids were sharply decreased by thermal oxidation whereas the saturated fatty acid contents ranging 10-17% were not changed considerably, which largely agreed with the results of iodine value measurements. The free acid and peroxide values were also lowest in soybean oil (0.09 and 5.6 respectively) among the unheated oils whereas an anomalously high free acid value was observed in rapeseed oil (54.8) which was packed in unleveled glass bottles. Such a high value is probably ascribed to the photo-catalyzed oxidation during storage. The viscosity measurements have shown similar values before heating, but after thermal oxidation for 32 hours the rapeseed and rice bran oils became too thick to measure viscosity by capillary flow method with heavy darkening in color.

• Economic and Environmental Geology
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• v.47 no.2
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• pp.87-96
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• 2014

The objectives of this study were to characterize the physicochemical properties and mineralogy of Hwangto (yellow residual soils) from the southwestern part of Korea and to understand the soil-forming processes of the residual soils from their parent rocks. Both the yellowish residual soils as well as the unweathered and weathered parent rocks were obtained from Jangdong-ri, Donggang-myun, Naju, Jeollanam-do, Korea. The soil samples were examined to analyze the said soil's physicochemical properties such as color, pH, and particle size distribution. A scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis were performed in order to understand the mineralogy, chemical composition, and morphology of the soils. Two thin sections of a parent rock were analyzed to study its mineral composition. A particle size analysis of the soils indicates that the residual soil consists of mainly silt and clay (approximately 95%) and that soil textures are silty clay or silt clay loam. The soil colors of the residual soil are dark brown (7.5YR 3/4) through yellowish red (5YR 4/6). The pH of the residual soil ranges from 4.3 to 5.1. The major minerals of the parent rocks were quartz, biotite, chlorite, and plagioclase. The mineralogy of the sand fraction of the residual soil was quartz, biotite, muscovite and sanidine. The mineralogy of the silt fraction of the residual soil was quartz, biotite, muscovite, Na-feldspar, K-feldspar, and sanidine. The clay mineralogy of the soil was goethite, kaolinite, ilite, hydroxy-interlayed vermiculite(HIV), vermiculite, mica, K-feldspar and quartz. The mineral composition of the residual soil and the parent rock indicates that feldspar and mica in the parent rock weathered into illite, vermiculite and hydroxy-interlayed vermiculite(HIV), and finally changed into kaolinite and halloysite in the yellowish residual soils.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.242-256
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• 1997

The physico-chemical properties and possible biological functionalities of commercially available persimmon vinegars were studied by measuring the specific gravity, turbidity, color, pH, total acidity, reducing sugars, alcohols, total nitrogen content, composition of organic acids and amino acids, soluble pectin, soluble tannin, ascorbic acid, acetoinic compounds, electron donating ability and nitrite scavenging ability. Persimmon vinegars had low specific gravity(1.005-1.0200) and lightness(40.03-54.95), but high turbidity (0.12-1.311, absorptivity at 660 nm), redness(1.65--0.64) and yellowness(4.54-8.14) compared to the other fruit vinegars reported. These physical property values of the individiual product differed greatly. The tested persimmon vinegars contained relatively large amount of reducing sugars(0.45-0.84%, w/v), alcohol(0.16-3.18%, w/v) and total nitrogen(30-60mg%, w/v). The pH values (average 3.70) of products were relatively high and the total acidities(average 3.04%, w/v) of the tested persimmon vinegars were lower than that($TA{\geq}4.0%$) specified by the Korean standard for fruit vinegar. The major organic acids identified in the tested products were acetic acid(17.6-72.9%) and lactic acid(25.1-74.1%). The acetic acid contents in the 5 products out of the 7 tested persimmon vinegars were lower than lactic acid content. The level of free amino acids of the persimmon vinegars were relatively high in arginine, methionine and threonine. Persimmon vinegars contained relatively large amount of soluble pectin(91.8-232.8mg%, w/v), soluble tannin(49.0-161.7mg%, w/v) and ascorbic acid(12.8-29.6mg%, w/v). The persimmon vinegars were high in 2,3-butanediol (average 166.90ppm) and acetoin(average 111.43ppm). The persimmon vinegars showed strong electron donating ability and nitrite scavenging ability.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.87-102
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• 1980

In order to investigate the utilization probability of two years old laying hen for W.L. and R.I.R. breeds, carcass weight and percentage were examined and dried old chicken meat products were manufactured for experiments. The results obtained are as follows. 1. Average living body weight were 1,635.40g for the W.L. breeds and 2,289.29g for the R.I.R. breeds and percentage carcass and lean meat for the W.L. were 58.73% and 43.95%, for the R.I.R. 60.34%, 41.98%, respectively. 2. In constitution percentage of carcass on different parts for W.L. and R.I.R. breeds, head were 4.13% and 3.94%, wing 9.97% and 8.62%, breast 32.54% and 20.94%, back 11.35% and 9.75%, thigh 30.75% and 31.34%, hypordermic fat 11.37% and 17.34%, respectively. 3. In constitution percentage of lean meat on different parts for W.L. and R.I.R. breeds, head were 4.03% and 3.95%, wing 9.47% and 9.79%, breast 39.37% and 38.14%, back 11.24% and 9.40%, thigh 36.16% and 38.74%, respectively. 4. In chemical composition of old chicken meat for W.L. breed, moisture was 68.18%, crude protein 22.80%, crude fat 2.70%, extract 5.15% and crude ash 1.18% and for R.I.R. breed, moisture was 68.04%, crude protein 22.18%, crude fat 3.13%, extract 5.45% and crude ash 1.21%. 5. Weight loss in steaming for W.L. at $121^{\circ}C$ for 30min., 60min., and 90min. were 54.91, 56.43 and 58.42%, respectively, and for R.I.R. were 45.23, 47.68 and 49.68%, respectively. 6. The yield of old chicken meat product per a hen were 253.01g for W.L. and 368.64g for R.I.R., the ratio for fresh meat weight and for carcass weight were 35.47% and 26.34% for W.L. breed and 38.25 and 26.83% for R.I.R. breed. 7. In chemical composition of old chicken meat product for W.L., moisture was 16.69%, crude protein 66.16%, crude fat 12.81%, crude ash 4.35%, and R.I.R., moisture 16.11%, crude protein 65.95%, crude fat 13.78% and crude ash 4.57%. 8. To investigate the physical properties which was main factor affecting the product quality, tensile strength, tear strength and elongation rate were measured. The adhesive force of the product made under pressure of $70kg/cm^2$ was similar to those of chipo which was the control product. 9. When measured the color of each protein product, lightness of the product pressed at $70kg/cm^2$ was better than that at $35kg/cm^2$, and the lightness of breast muscle product at $70kg/cm^2$ and chipo was not significant as 16.7% and 16.4%, respectively. Dominant wavelength of product pressed at $70kg/cm^2$ was very similar to chipo which was yellowish orange. 10. In the results of sensory evaluation test containing taste, color, chewing texture and oder of the meat product, when index of chipo as control product was 100, index of breast meat product was higher than that as 118.4, but miscellaneous product was 99.7 and thigh product was 96.2. 11. Summing up the results written above, the meat product utilizing two years old laying hen was compared favorably with its similar food such as chipo on the point of nutrition and physical properties as high protein food, therefore, it was thought that industrialization must be highly appropriate.

• Applied Chemistry for Engineering
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• v.31 no.1
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• pp.43-48
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• 2020

Fe₂O₃ nanoparticles with the mixed structure of cubic and nanorod were synthesized by precipitation, hydrothermal, sol-gel method, etching process and heat treatment. Fe₂O₃/TiO₂ core-shell (CS) of type Fe₂O₃@TiO₂ composite was fabricated on a 20 nm nanolayer of TiO₂ coated on the surface of Fe₂O₃ nanoparticles. Fe₂O₃/TiO₂ yolk-shell (YS) composite was prepared by chemical etching and heat treatment of Fe₂O₃/TiO₂ CS nanoparticles. Physical properties of Fe₂O₃, Fe₂O₃@TiO₂ CS and Fe₂O₃@TiO₂ YS nanoparticles were characterized by FE-SEM, HR-TEM and X-ray diffraction. The solar reflectance, commission internationale de l'Elcairage (CIE) color coordinate and heat shield temperatures of Fe₂O₃, CS and YS type Fe₂O₃@TiO₂ pigments filled with poly acrylate (PA) paints were investigated by UV-Vis-NIR spectrometer and homemade heat shield temperature measuring device. The Fe₂O₃@TiO₂ YS red pigment filled PA composite exhibited excellent near infrared light reflecting performance and also reduced the heat shield temperature of 13 ℃ than that of Fe₂O₃ filled counterparts.