• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.466-473
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• 2018

An analytical method of sodium polyacrylate in processed food products was developed and monitored by using size-exclusion chromatography. GF-7M HQ column and UV/VIS detector were selected based on peak shape and linearity. Flow rate, column oven temperature, and mobile phase were selected as 0.6 mL/min, $45^{\circ}C$, and 50 mM sodium phosphate buffer of pH 9.0, respectively. Samples for analysis of sodium polyacrylate were extracted with 50 mM sodium phosphate buffer of pH 7.0 for 3 hr at $20^{\circ}C$ and 150 rpm. Analytical method validation revealed proper selectivity and calibration curve was selected in the range of 50-500 mg/L, and correlation coefficient of calibration curve was more than 0.9985. Limit of detection of sodium polyacrylate was 10.95 mg/kg and limit of quantification was 33.19 mg/kg. Accuracy and coefficient of variation for sodium polyacrylate analysis was 99.6-127.6%, 3.0-8.3% for intra-day and 94.3-121.9%, 1.3-2.6% for inter-day, respectively. Sodium polyacrylate was detected in 40 samples among monitored 125 processed food products. Detected contents were less than 0.2%, limited by the Food Additives Code. Results suggest the established size-exclusion chromatography method could be used to analyze sodium polyacrylate in processed food products.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.620-631
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• 2019

Be an important competitive appearance for both boys and girls in modern society, and highlight the importance of enhancing their appearance. Administrative activity is considered traditionally feminine behavior and appearance, almost all female is subject of a consumer market is continuing, and recognition, but since the 1990s.Gender role stereotypes and women's social activity due to changes in status and role of men and women affected. Accordingly, the men in the realm of women than it used to be a glass half full and inclusive attitude began to improve her appearance are also men, and well in yourself. Investing a lot of time and money to their appearance to describe behavior. Furthermore, workers men to appearance factor for the career achievement, such as promotion or salary competitiveness is gradually spreading awareness of social life on whose behalf the men. The halo effect for a positive image formation and desirable looks to be. A Study on the self-wor Second, the higher the self-esteem of psychologically stable social approval of the important aesthetic of clothing, is less dependent on increased manageability and clothing. The study by analysis of the self respect persimmon and appearance for his own body satisfaction and a high correlation study and OK. Interpersonal and that a significant impact on the formation.Be an important competitive appearance for both boys and girls in modern society, and highlight the importance of enhancing their appearance. Administrative activity is considered traditionally feminine behavior and appearance, almost all female is subject of a consumer market is continuing, and recognition, but since the 1990s.Gender role stereotypes and women's social activity due to changes in status and role of men and women affected. Accordingly, the men in the realm of women than it used to be a glass half full and inclusive attitude began to improve her appearance are also men, and well in yourself. Investing a lot of time and money to their appearance to describe behavior. Furthermore, workers men to appearance factor for the career achievement, such as promotion or salary competitiveness is gradually spreading awareness of social life on whose behalf the men. The halo effect for a positive image formation and desirable looks to be. A Study on the self-wor Second, the higher the self-esteem of psychologically stable social approval of the important aesthetic of clothing, is less dependent on increased manageability and clothing. The study by analysis of the self respect persimmon and appearance for his own body satisfaction and a high correlation study and OK. Interpersonal and that a significant impact on the formation.

• Korean Journal of Heritage: History & Science
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• v.47 no.3
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• pp.24-41
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• 2014

Since the celadons excavated from the Son-gok 2-ri 4th kiln site are located in the Beopcheon temple site and at close range, the similarity to the celadons excavated from the Beopcheon temple site is being raised. Thus, this study examined the correlation using a natural-scientific method. In this study, historical ceramic properties of total 19 celadons were examined and they were scientifically analyzed. First of all, according to the scientific analysis, chemical compositions of celadon clay showed a dispersed distribution at RO2 3.79-7.77mole and RO+R2O 0.33-0.49mole. When the microstructure was analyzed, most celadons excavated from the Beopcheon temple site, Wonju, which are estimated to be used in real life, had a favorable state, and some celadons from the Son-gok 2-ri 4th kiln site were found not to be glazed and sintered properly. When analyzing body crystalline phases of the celadons using the XRD method, quartz and mullite were extracted from all of the samples. And corundum was extracted from sg4 sample. Though firing temperature of each sample was different, they were mostly fired to temperatures between 1150 and $1200^{\circ}C$ and some of them experienced a low temperature of $1100^{\circ}C$ or a high temperature above $1200^{\circ}C$. Various chemical compositions and producing techniques were observed in the celadons from the Beopcheon temple site and Son-gok 2-ri 4th kiln site and it is hard to assure that the Son-gok 2-ri 4th kiln site was the production kiln site of the celadons used in the Beopcheon temple site. But according to the analysis of rare earth elements, some of the celadons from the Beopcheon temple site and Son-gok 2-ri 4th kiln site displayed a distribution pattern with certain regularity and this implies there is a possibility that the raw materials used in producing the ceramics might have come from the same origin. From the perspective of ceramic history, the celadons excavated from the Beopcheon temple site and Son-gok 2-ri 4th kiln site were produced using the same molding and sintering technique. Also, it is estimated that they were produced in the 12th or 13th century, judging from the overall shapes and patterns of the celadons.

• Korean Journal of Heritage: History & Science
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• v.47 no.4
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• pp.224-243
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• 2014

This study examined the materials and casting technology(cast, alloy, etc.) used in the manufacturing of bronze artifacts based on old literature such as Yongjae Chonghwa, Cheongong Geamul, and The Korea Review. In the casting experiment for restoration of Sangpyong Tongbo, a bronze and brass mother coin mold was made using the sand mold casting method described in The Korea Review. The cast was comprised of the original mold plate frame, wooden frame, and molding sand. Depending on the material of the outer frame, which contains the molding sand, the original mold plate frame can be either a wooden frame or steel frame. For the molding sand, light yellow-colored sand of the Jeonbuk Iri region was used. Next, the composition of the mother alloy used in the restoration of Sangpyong Tongbo was studied. In consideration of the evaporation of tin and lead during actual restoration, the composition of Cu 60%, Zn 30%, and Pb 10% for brass as stated in The Korea Review was modified to Cu 60%, Zn 35%, and Pb 15%. For bronze, based on the composition of Cu 80%, Sn 6%, and Pb 14% used for Haedong Tongbo, the composition was set as Cu 80%, Sn 11%, and Pb 19%. The mother coin mold was restored by first creating a wooden father coin, making a cast from the wooden frame and basic steel frame, alloying, casting, and making a mother coin. Component analysis was conducted on the mother alloy of the restored Sangpyong Tongbo, and its primary and secondary casts. The bronze mother alloy saw a 5% increase in copper and 4% reduction in lead. The brass parent alloy had a 5% increase in copper, but a 4% and 12% decrease in lead and tin respectively. Analysis of the primary and secondary mother coin molds using an energy dispersive spectrometer showed that the bronze mother coin mold had a reduced amount of lead, while the brass mother coin mold had less tin. This can be explained by the evaporation of lead and tin in the melting of the primary mother coin mold. In addition, the ${\alpha}$-phase and lead particles were found in the mother alloy of bronze and brass, as well as the microstructure of the primary and secondary coin molds. Impurities such as Al and Si were observed only in the brass mother coin mold.

• Korean Journal of Heritage: History & Science
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• v.50 no.4
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• pp.198-221
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• 2017

The Jjoksaem site is the eastern sector of Daereungwon Ancient Tomb Complex, Gyeongju(the 512th Historic site) called Wolseong North Burial Ground in academic community. The excavation and research of this site was conducted from 2007 to 2015, with the purpose of basic data offering for the restoration of Silla tumuli and development of ancient tomb park. As a result of the investigation, more than 700 new tombs were discovered except the 155 tumuli founded in the Japanese colonial era. Moreover, more than 70 percent of the smaller tombs, such as outer coffin tombs, were discovered here. There are four characteristics of outer coffin tombs in Jjoksaem site. First, it is recognized the Gyeongju-styled outer coffin tombs have a long rectangular shape, distinct from Gimhae-styled outer coffin tombs in a rectangular shape. Second, they are divided into three groups by the size of the grave area. This is indirectly related to the rank and the status of the buried person. Third, these tombs began to be constructed at the end of the 3rd century before the time of wooden chamber tombs covered by stone and earthen mound. They were ruined because of the new tombs constructed at the period of Maripgan. This reflects that the identity of the former tombs was not respected by the communities in the later generations. Outer coffin tombs were consistently made to the end of the era of wooden chamber tombs covered by stone and earthen mound. Lastly, the area of burial ground of outer coffin tombs is limited by wooden chamber tombs covered by stone and wooden mounds. Otherwise, the location of the burial ground for the deceased is limited by the status of the deceased. The idea that wooden chamber tombs covered by stone and earthen mound are located on the above ground turns out to be incorrect. In Jjoksaem site, there is little difference between the height of the circular burial protection stone and the height of the digging lines of the other tombs. In the case of No.44 tumulus, the lowest step of the circular burial protection stones is lower than those of the other tombs and tumuli. Research of outer coffin tombs at Jjoksaem site will be to suggest important academic data about the changing period from Saroguk, as the head of chiefdom union, to Silla, as state.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.2
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• pp.61-67
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• 2019

This study was conducted to investigate the effect of supplementary feeding levels on livestck and forage productivity and grazing intensity in Elk stags (Cervus canadensis). A fifteen 2-year-old Elk stags about 195 kg were randomly assigned to one of three dietary treatments (five animals per treatment). The dietary treatments consisted of a feeding concentrate of 1.0% of body weight (T1), 1.5% of body weight (T2) and 2.0% of body weight. Total dry matter intake (TDMI) was increased with increased with an increasing supplementary feeding levels. Average daily gain (ADG) were significantly increased with an increasing supplementary feeding levels (p<0.05) and reached a maximum on July and was lower in spring than autumn. The velvet antler production was no differences among treatment groups. Forage productivity of pasture and crude protein content were highest on May and decreased thereafter, however, crude fiber content was the reversed. The grazing intensity of Elk stags was increased in spring (38 to 59 head per ha) than summer and autumn (13 to 32 head per ha). The average grazing intensity of Elk stags ranged from 21 to 34 head per ha, which is affected by supplementary feeding levels. This result suggests that feeding supplementary diet at 1.5 % of body weight was needed to maintain the stable wight gain in antler growing periods and control the proper grazing intensity of Elk deer stags.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.255-264
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• 2019

In this study, we conducted the hot box tests to compare the changes in thermal insulation for the four types of multi-layer thermal screens by the used period after collecting them from the greenhouses in the field when they were replaced at the end of their usage. The main materials for these four types of multi-layer thermal screens were matt georgette, non-woven fabrics, polyethylene (PE) foam, chemical cotton, etc. These materials were differently combined for each multi-layer thermal screen. We built specimens ($70{\times}70cm$) for each of these multi-layer thermal screens and measured the temperature descending rate, heat transmission coefficient, and thermal resistance for each specimen through the hot box tests. With regard to the material combinations of multi-layer thermal screens, thermal insulation can be increased by applying a multi-layered PE foam. However, it is considered that the multi-layered PE foam significantly less contributes to heat-retaining than chemical wool that forms an air-insulating layer inside multi-layer thermal screens. For the suitable heat-retaining performance of multi-layer thermal screens, basically, materials with the function of forming an air-insulating layer such as chemical cotton should be contained in multi-layer thermal screens. The temperature descending rate, heat transmission coefficient, and thermal resistance of multi-layer thermal screens were appropriately measured through the hot box tests designed in this study. However, in this study, we took into consideration only the four kinds of multi-layer thermal screens due to difficulties in collecting used multi-layer thermal screens. This is the results obtained with relatively few examples and it is the limit of this study. In the future, more cases should be investigated and supplemented through related research.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.243-254
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• 2019

With the recent accelerated policy-making and interests in new renewable energy, plans to develop and supply the new renewable energy have been devised across multiple regions in Korea. Solar energy, in particular, is being applied to small-scale power supply in provincial areas, as solar cells are used to convert solar energy into electric energy to produce electric power. Nonetheless, in the case of solar power plants, the need for a large stretch of land and considerable sum of financial support implies that the planning step should take into consideration the most suitable meteorological and geographical factors. In this study, the proxy variables of meteorological and geographical factors associated with solar energy were considered in analyzing the vulnerable areas regarding the photovoltaic power generation facility across the nation. GIS was used in the spatial analysis to develop a map for assessing the optimal location for photovoltaic power generation facility. The final vulnerability map developed in this study did not reveal any areas that exhibit vulnerability level 5 (very high) or 1 (very low). Jeollanam-do showed the largest value of vulnerability level 4 (high), while a large value of vulnerability level 3 (moderate) was shown by several administrative districts including Gwangju metropolitan city, Jeollabuk-do, Chungcheongbuk-do, and Gangwon-do. A value of vulnerability level 2 (low) was shown by the metropolitan cities including Daegu, Ulsan, and Incheon. When the 30 currently operating solar power plants were compared and reviewed, most were found to be in an area of vulnerability level 2 or 3, indicating that the locations were relatively suitable for solar energy. However, the limited data quantity for solar power plants, which is the limitation of this study, prevents the accuracy of the findings to be clearly established. Nevertheless, the significance of this study lies in that an attempt has been made to assess the vulnerability map for photovoltaic power generation facility targeting various regions across the nation, through the use of the GIS-based spatial analysis technique that takes into account the diverse meteorological and geographical factors. Furthermore, by presenting the data obtained for all regions across the nation, the findings of this study are likely to prove useful as the basic data in fields related to the photovoltaic power generation.

• Korean Journal of Heritage: History & Science
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• v.50 no.1
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• pp.18-41
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• 2017

The Gangjin WolnamSaji(月南寺址) is a small site where three-story pagodas and a destroyed tombstone remained. In 1973, it was discovered that the destroyed tombstone was that of the second master of Susunsa, Hye shim(慧諶), who had a special relationship with the military regime in Goryeo, and it once again attracted attention as a result of the recent excavation of the Rooftile of Yeonhwamun(蓮花文). In particular, the Windchime excavated in 2012 is a large-sized one group with a length of 23cm, and a relatively large Sanskrit character was decorated on four sides of the body. In addition, it was also confirmed in preservation process that the word 'gaecheon(盖天)' was engraved. The Sanskrit characters(梵字) om( , oṃ), a( , a), hum( , hūṃ), brum( , bhrūṃ) were decorated on the body of the Wind-chime excavated in WolnamSaji. Om( , oṃ), a( , a), hum( , hūṃ) are known as the Sammiljineon(三密眞言) and brum( , bhrūṃ) has the meaning of having the highest honor. In addition, the Sammiljineon(三密眞言) allows us to understand the truth by responding to the principle of universe, which is the Vairocana Buddha(毘盧遮那佛), and brum( , bhrūṃ) has the meaning of unity. In the end, the meaning of the Sanskrit decorating the four sides of the Wind-chime, of WolnamSaji(月南寺址), can be interpreted as the expression of the Buddha's doctrine, or the willingness to be combined with Buddha, the highest existence in itself. It is possible that the word 'gaecheon(盖天)' carved on the body can be regarded as the name of the master craftsman related to the making of the Wind-chime, but it is unlikely that it is the name of the master craftsman, considering that it is a place where the location is not easily seen. If so, you can think of the original function that the Wind-chime has. In other words, it can be interpreted symbolically and implicitly that the wish of the sound of the airwaves symbolized by the words of the Buddha covers the sky and spreads all over the place. It is thought that the Wind-chime excavated in WolnamSaji(月南寺址) was made in the mid to late 13th century considering the comparisons with another wind-chime excavated from the temple site, the historical situation in the late Goryeo, the publication date of the scriptures(經典) of Esoteric Buddhism(密敎).

• Journal of Life Science
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• v.29 no.6
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• pp.679-687
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• 2019

Litsea populifolia, a plant species of the Lauraceae family, is widely distributed in the tropical and subtropical areas of Asia. The phylogenetic relationships and botanical characteristics of L. populifolia have been reported; however, its anti-oxidative and anti-cancer activities remain unclear. In this study, we evaluated the anti-oxidative and anti-cancer effects of ethanol extracts of L. populifolia (EELP) together with the molecular mechanism of its anti-cancer activity in human lung adenocarcinoma A549 cells. EELP showed significant anti-oxidative effects with a 50% inhibitory concentration at $11.71{\mu}g/ml$, which was measured by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay. EELP exhibited cytotoxic activity and induced cell cycle arrest at the G1 phase in A549 cells in a dose-dependent manner, whereas EELP did not have the cytotoxic effect on the normal human lung cell line IMR90. Treatment with EELP also resulted in a decreased expression of G1/S transition-related molecules-including cyclin-dependent kinase (CDK) 2, CDK6, cyclin D1, and cyclin E-both for the transcription and translation levels. EELP-induced G1 arrest was associated with the phosphorylation of checkpoint kinase 2 (CHK2), p53, cell division cycle 25 homolog A (CDC25A), and the reduction of CDC25A expression in A549 cells. Collectively, these results suggest that EELP may exert an anti-cancer effect by cell cycle arrest at the G1 phase through both p53-dependent and p53-independent (ATM/CHK2/CDC25A/CDK2) pathways in A549 cells.