• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.414-419
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• 2010

Plants extracts are good resources to find functional compounds for human health. The following eight plants were collected and total phenolic contents were determined. Acer psedo-siebolianum showed the highest phenolic contents, 16.4 mg/g, whereas Cercidiphyllum japonica showed the lowest contents, 1.9 mg/g. The DPPH free radical scavenging capacities of the plant extracts showed high activity in following order : Acer ginnala ($21.3\;{\mu}g/mL$) > Cornus walteri ($23.9\;{\mu}g/mL$) > Distylum racemosum ($29.2\;{\mu}g/mL$) > Castanopsis cuspidata var. Thunbergii ($31.7\;{\mu}g/mL$) > Acer psedo-siebolianum ($34.6\;{\mu}g/mL$) > Thuijopsis dolabrata cv. Aurea ($53.1\;{\mu}g/mL$) > Cercidiphyllum Japonica ($115.2\;{\mu}g/mL$). Also the mushroom tyrosinase inhibitory activities of total extracts were determined at different concentration. D. racemosum extract showed highest (49.1% at 1,000 mg) in inhibitory activity than other seven extracts. The ethanol fraction $IC_{50}$ value: $118.1\;{\mu}g/mL$) from D. racemosum showed more inhibitory activity than ethyl acetate fraction ($IC_{50}$ value: $203\;{\mu}g/mL$). The ethanol fraction on showed no significant cytotoxicity in B16/F1 cells line up to $60\;{\mu}g/mL$. Over $80\;{\mu}g/mL$ of ethanol fraction showed cytotoxicity in B16/F1 cells. The melanin contents of cells were significantly attenuated by ethanol fraction in a dose-dependent manner. The $IC_{50}$ value of ethanol fraction was $75.4\;{\mu}g/mL$.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.179-187
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• 2016

This study was conducted to determine the impact of elevated temperature and $CO_2$ concentration based on climate change scenario on growth and fruit quality of pepper (Capsicum annuum L. cv. Muhanjilju) with SPAR (Soil Plant Atmosphere Research) chamber. The intraday temperatures of climate normal years fixed by $20.8^{\circ}C$ during the growing season (May 1~October 30) of climatic normal years (1971~2000) in Andong region. There were treated with 4 groups such like a control group (ambient temperature and 400ppm $CO_2$), an elevated $CO_2$ group (ambient temperature and 800ppm $CO_2$), an elevated temperature group (ambient temperature+$6^{\circ}C$ and 400ppm $CO_2$) and an elevated temperature/$CO_2$ group (ambient temperature+$6^{\circ}C$ and 800ppm $CO_2$). Compared with the control, plant height, branch number and leaf number increased under the elevated temperature and elevated temperature/$CO_2$ group. However, leaf area and chlorophyll content showed a tendency of decreasing in the elevated temperature group and elevated temperature/$CO_2$ group. The number of flower and bud were decreased in the elevated temperature and elevated temperature/$CO_2$ group (mean temperature at $26.8^{\circ}C$) during the growth period. The total number and the weight of fruits were decreased in the elevated temperature group and elevated temperature/$CO_2$ group more than the control group. While the weight, length and diameter of fruit decreased more than those of control as the temperature and $CO_2$ concentration increased gradually. This result suggests that the fruit yield could be decreased under the elevated temperature/$CO_2$ ($6^{\circ}C$ higher than atmospheric temperature/2-fold higher than atmospheric $CO_2$ concentration), whereas the percentage of ripen fruits after 100 days of planting was increased, and showed earlier harvest time than the control.

• Journal of Conservation Science
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• v.34 no.6
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• pp.595-604
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• 2018

In this study, in a bid to develop natural bioadhesives for paper craft, the hanji industry, and preserving cultural assets, complex polysaccharides were extracted from brown and red algae and used as an ingredient in adhesives. Brown algae include sea trumpet, kelp, sea oak, and sea mustard, whereas red algae include Pachymeniopsis elliptica agar-agar weed, Gloiopeltis tenax, and hunori. The polysaccharides were extracted after transforming them from non-aqueous Ca complexes contained in each of the brown and red algae into water-soluble polysaccharides containing alkali metals with a solubility level of 1. and extracted Subsequently, only the polysaccharides were extracted using alcohol precipitation. The adhesion tensile strengths of kelp, a brown algae, and Pachymeniopsis elliptica, a red algae, were 21.58 and 32.99 kgf, respectively. They thus demonstrated better adhesion than that of solid glue products such as water plants (18.45 kgf) and glue sticks (20.45 kgf). The extraction yield of these polysaccharides is supposed to be determined according to their extracted environments; however, no difference in adhesion strength was seen. Further, it was found that the shapes of polysaccharides were determined by their growing environment instead of extraction environment. Use of multi-step alcohol precipitation method during extraction enabled the removal of the constituents except protein and other polysaccharides, thereby demonstrating a stable outcome without cultivation of mold. Furthermore, there was no occurrence of mold even after production of the adhesives by the simple solution method, which demonstrates the adhesive's potential as an environment-friendly adhesive material.

• Journal of the Daesoon Academy of Sciences
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• v.37
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• pp.297-328
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• 2021

This paper aims to find out from what perspective Joseon Dynasty Confucian scholars evaluated and understood Yang Xiong's guiding principles and literature at the micro level and to reveal the academic trends of Joseon Dynasty Confucian scholars. This topic is approached as follows: first, an evaluation of Yang Xiong's way of living as a 'senior state official of Wang Mang (the controversial Emperor of the short-lived Xin Dynasty)'; second, Yang Xiong's literary character and his literary works; third, Yang Xiong's writing style; and fourth, Yang Xiong's view of good and evil. These can be summarized in three main ways: One is to agree with Zhu Xi's criticism of Yang Xiong as a 'senior state official of Wang Mang' and dismiss his guiding principles, academic achievements, literature, and other accomplishments. Most of these negatives have been found in Confucian scholars who are especially enthusiastic about theology. Examples include Hong Jikpil, Wi Baekgyu, Kim Wonhaeng, and Lee Sangjeong. In the case of kings such as King Yeong-Jo, the assessment of Yang Xiong is quite similar. The following assessments of Yang Xiong are positive though. Positive assessments are presented from two different views. One is a balanced approach that covers both the positive and negative aspects of Yang Xiong. For example, Heo-Kyun's understanding. Another positive view can be analyzed from three perspectives. The first case is when the scholars assessing Yang Xiong were not deeply influenced by Zhu Xi's criticism of him. Seo Geojeong and Seong-Hyeon are examples. The second case are those that broke away from theology or adhered to Silhak [Practical Studies]. Yi-Ik is an example. Third, assessments from scholars who posited that truth was of a pluralistic nature. Jang-Yu is an example of such scholars. Regarding theories of human nature; however, there was consensus among Confucian scholars that Mengzi held that human nature is good, and thereby it was common to criticize Yang Xiong's theory that human nature was a mixture of good and evil. From an ideal micro perspective, Joseon Dynasty Confucian scholars' different assessments of Yang Xiong show that their understanding and evaluation of Yang Xiong differed in accordance with their own differing worldviews and ideas.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.125-132
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• 2014

Objectives : Suryeon-hwan (SRH) exhibits potent anti-inflammatory activity with an unknown mechanism. However, there has been a lack of studies regarding the effects of SRH on the inflammatory activities and effector inflammatory disease mechanism about macrophage before is not known. So, the investigation focused on whether SRH inhibited nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) productions, as well as the expressions of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and mitogen-activated protein kinases (MAPKs) in LPS-stimulated RAW 264.7 cells. Methods : Cells were treated with 200 ng/mL of LPS 30 min prior to the addition of SRH. Cell viability was measured by MTS assay. The production of nitric oxide (NO) was determined by reacting cultured medium with Griess reagent. The content of level of cytokines (PGE, IL-6) in media from LPS-stimulated Raw 264.7 cells was analyed by ELISA kit. The expression of COX-2, iNOS and MAPKs was investigated by Western blot, RT-PCR. Results : We found that SRH inhibited LPS-induced NO, $PGE_2$ and IL-6 productions as well as the expressions of iNOS and COX-2. Furthermore, SRH suppressed the LPS-induced phosphorylation of MAPK and extracellular signal-regulated kinase 1/2 (ERK 1/2) activation. Conclusions : These results suggest that SRH has inhibitory effects on LPS-induced $PGE_2$, NO, and IL-6 production, as well as the expressions of iNOS and COX-2 in the murine macrophage. These inhibitory effects occur through blockades on the phosphorylation of MAPKs following activation.

• Korean Security Journal
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• no.36
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• pp.139-176
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• 2013

It is believed that the Koryo dynasty era is the period which has very special meaning with regard to the history of the VIP guard system. The guard system in the early Koryo dynasty time focused on the official protection for kings and their families with absolute royal authority. On the contrary, the guard system in the late Koryo dynasty time, especially military regime period, conducted providing private protection for military rulers and increasing their power. The official guard troops named 2Gun6Wii became just perfunctory organizations at that time. That is the reason why this study develops the discussion only about the guard system of the early Koryo time. The official VIP guard organizations under the government structure of the early Koryo period were Naegoonbu, Byeongbu and Joongchoowon. This study particularly reviewed the Joongchoowon with thorough research. In the meantime, the guard organizations under the military chart of the early Koryo period were 2Gun6Wii, Gonghakgoon, Geonryonggun and so on. 2Gun consisted of ungyanggun and yonghogun. They were the royal bodyguards. This study especially tried to review the substance of the Gonghakgoon, Geonryonggun with different point of view from other theories. The Gumowwii, one of 6 Wii, conducted many official duties such as royal palace protection, capital city Gaesung defence, area patrols, criminal apprehension and disturbance prevention. It also accomplished crowd control and convoy mission at the streets to respond emergency cases while carrying out VIP protection roles for kings and Chinese diplomats. Many bibliographies verified that the Chunwoowii was the royal bodyguards which helped kings during state ceremonies and grand meetings held by kings. Consequentially, it is true that this study discovered, analyzed and evaluated various references and research materials related with the guard system. It is meaningful that this study newly reviewed the organizations and functions of the guard system as one structure.

• Conservation Science in Museum
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• v.13
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• pp.23-31
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• 2012

The object artifacts of this study are the iron artifacts owned by the Kyunghee University Central Museum. The surfaces of the iron artifacts are opaque due to the coated materials which are presumed to be paraffin or bee's wax while they are plate-shaped and exist in thickly exfoliated condition caused by severe corrosion developed on the overall surfaces. Therefore, in order to remove the coated materials away from the surfaces of the artifacts rather safely, reversibility tests have been carried out and the conservation treatment was performed upon the basis of and in application of the experimental results. The study methodologies are that: first, the FT-IR analysis was carried out to determine the ingredients of the coating-treated material on the surface; second, by applying various kinds of organic solvents, the kinds of agents that allow the artifact's surface-coating material to be reversible have been identified through experiments; third, the most suitable agent for removing coating material was selected and applied to the real artifacts on the basis of the results of the reversibility tests. Results from the study: first, as a result of the FT-IR analysis, the coating agent used on the artifacts was identified to be of the same ingredients as those of paraffin; second, among organic solvents, xylene, toluene, trichloroethylene and methyl alcohol were identified to be usable for dissolving paraffin whereas toluene was judged to be the most suitable for removing the coating agent; third, when applying the selected agents on the real artifacts, due to the fact that removing the whole paraffin might cause the artifact to disintegrate, the paraffin of only the part that covered the surfaces opaquely was removed using cotton swab or gauze, thus completing the conservation treatment.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.863-870
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• 2016

We investigated the physical/chemical phenomena that a slow loss of $CO_2$ inventory into sodium after the sodium-$CO_2$ boundary failure in printed circuit heat exchangers (PCHEs), which is considered for the supercritical $CO_2$ Brayton cycle power conversion system of a sodium-cooled fast reactor (SFR). The first phenomenon is plugging inside narrow sodium channels by micro cracks and the other one is damage propagation referred to as wastage combined with the corrosion/erosion effect. Experimental results of plugging shows that sodium flow immediately stopped as $CO_2$ was injected through the nozzle at $300{\sim}400^{\circ}C$ in 3 mmID sodium channels, whereas sodium flow stopped about 60 min after $CO_2$ injection in 5 mmID sodium channels. These results imply that if pressure boundary of sodium-$CO_2$ fails a narrow sodium channel would be plugged by reaction products in a short time whereas a relatively wider sodium channel would be plugged with higher concentration of reaction products. Wastage by the erosion effect of $CO_2$ (200~250 bar) hardly occurred regardless of the kinds of materials (stainless steel 316, Inconel 600, and 9Cr-1Mo steel), temperature ($400{\sim}500^{\circ}C$), or the diameter of the $CO_2$ nozzle (0.2~0.8 mm). Velocities at the $CO_2$ nozzle were specified as Mach 0.4~0.7. Our experimental results are expected to be used for determining the design parameters of PCHEs for their safeties.

• Journal of IKEEE
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• v.23 no.4
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• pp.1461-1464
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• 2019

In this paper, we propose the development of embedded board for integrated radiation exposure protection fireman's life-saving alarm capable of location tracking and radiation measurement. The proposed techniques consist of signal processing unit, communication unit, power unit, main control unit. Signal processing units apply shielding design, noise reduction technology and electromagnetic wave subtraction technology. The communication unit is designed to communicate using the wifi method. In the main control unit, power consumption is reduced to a minimum, and a high performance system is formed through small, high density and low heat generation. The proposed techniques are equipment operated by exposure to poor conditions, such as disaster and fire sites, so they are designed and manufactured for external appearance considering waterproof and thermal endurance. The proposed techniques were tested by an authorized testing agency to determine the effectiveness of embedded board. The waterproof grade has achieved the IP67 rating, which can maintain stable performance even when flooded with water at the disaster site due to the nature of the fireman's equipment. The operating temperature was measured in the range of -10℃ to 50℃ to cope with a wide range of environmental changes at the disaster site. The battery life was measured to be available 144 hours after a single charge to cope with emergency disasters such as a collapse accident. The maximum communication distance, including the PCB, was measured to operate at 54.2 meters, a range wider than the existing 50 meters, at a straight line with the command-and-control vehicle in the event of a disaster. Therefore, the effectiveness of embedded board for embedded board for integrated radiation exposure protection fireman's life-saving alarm has been demonstrated.

• Korea journal of population studies
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• v.11 no.1
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• pp.159-184
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• 1988

Race and ethnicity are important factors which influence the elderIy's residential adjustment behaviors, although it is unclear whether this reflects influences unrelated to race and ethnlcity. Culturally, the norm of family supportoften obseved among various minority ethnic groups is likely to provide flexible family suppof for the elderIy. Economically, the life-long hardship ofminority groups is likely to force them to maintain extended family living arrangements simply to reduce expenses via economies of scale. Thecontroversy about the economic need versus the cultural prescription forextended living arrangements remains unresoIved because it fails to articulatethe meaning of family supports among many disadvantaged groups.This study aims to test previous economic and cultural arguments, byexamining ethnic differences iu the eiderIy's responsiveness to their health andeconomic problems. Two hypotheses about cultural influences on the elderly's resideutiai adjustment are examined. First, do elderly minorities receive famiiysupporis for longer periods when they are poor if economic and health status\ulcorner Second, do elderiy minorities receive family supports more often when their health status declines\ulcorner Using the Longitudinal Suvey on Aging from 1984 to 1990. this study employs Markovian multi-state life tables, and discrete and contonuous competing hazard analyses for the transition in living arrangements. The main results provide substantial evidence against the cultural resource thesis. Elderly minorities experience more frequent transition between living alone and living with relatives than white elderly persons when group differences in the extent of mortality and insititutionalization are controlled. The shorter timf of living alone among elderly monorities stems from their greater likehood of joining relatives as well as greater mortality and attrition rates than elderly whites. Coresidence of elderly whites with their relatives is more likely to occur in response to their needs for health care than of elderly whites. it implies that instability. not flezibility. characterrizes elderly minorities living arrangements.