• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.176-182
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• 2018

The purpose of this study was to investigate the safety and rationality of buckling strength and length coefficient by comparing with the design standards of domestic and foreign compression materials based on the buckling test results of circular steel pipe with ball joints. The types of round steel pipes selected for buckling performance evaluation were ø$48.6{\times}2.8t$, ø$60.5{\times}3.2t$ and ø$76.3{\times}3.2t$. For the design of domestic and foreign compression materials, Korea 's Load Resistance and Factor Design, Japan' s Limit State Design, and British Standard BS5950 standard were applied. In this study, we compared and analyzed the buckling performance between the experimental results of the previous research and the domestic and foreign design standards. The results were summarized as follows. As a result of applying the full length of the member to the buckling length in the compression materials design standards of each country, it was 64-89% of the buckling strength by the experiment. Therefore, it is deemed desirable to perform the member design according to the current design standard formula for safety. Experimental results show that the measured buckling strength was 1.02-1.43 times higher than the buckling strength of pure cylindrical steel tubes in the design standards of Korea, Japan and the United Kingdom compression materials. Consequently, it seemed that the buckling strength of individual member in the design of space frame structure should be considered buckling coefficient as the length of pure round steel pipe rather than the length of inter-node.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.4
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• pp.141-147
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• 2010

Liquefied natural gas(LNG) is natural gas that has been converted temporarily to liquid form for ease of storage and transport it. Natural gas is the worlds cleanest burning fossil fuel and it has emerged as the environmentally preferred fuel of choice. In Korea, the demand of this has been increased since the first import from the Indonesia in 1986. LNG takes up about 1/600th the volume of natural gas in the gaseous state by cooling it to approximately $-162^{\circ}C(-260^{\circ}F)$. The reduction in volume therefore makes it much more cost efficient to transport and store it. Modern LNG storage tanks are typically the full containment type, which is a double-wall construction with reinforced concrete outer wall and a high-nickel steel inner tank, with extremely efficient insulation between the walls. The insulation will be installed to LNG outer tank for the isolation of cryogenic temperature. The insulation will be installed in the base slab, wall and at the roof. According to the insulation's arrangement, the different aspects of temperature transmission is shown around the outer tank. As the result of the thermal & stress analysis, by the installing cellular glass underneath the perlite concrete, the temperature difference is greatly reduced between the ambient temperature and inside of concrete wall, also reducing section force according to temperature load.

• Journal of Life Science
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• v.23 no.10
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• pp.1223-1229
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• 2013

Ursolic acid (UA) a bio-active ingredient found in a variety of fruits and vegetables, and it has potent antioxidant activity. However, the role of UA in mouse embryonic stem (ES) cells is poorly understood. This study investigated the functional role of UA in regulating the development of mouse ES cells under hypoxia. Hypoxia did not exert a significant effect on the undifferentiated state of mouse ES cells. However, it induced reactive oxygen species (ROS) generation and increased the level of lactate dehydrogenase (LDH) production at 48 h of hypoxic exposure. Conversely, oxidative stress induced by hypoxia was significantly inhibited by UA ($30{\mu}M$) pretreatment. Hypoxia significantly decreased cell survival and the level of [$^3H$] thymidine incorporation, both of which recovered following pretreatment of UA. In addition, UA decreased the apoptotic effect of hypoxia by attenuating caspase-3 cleavage or by recovering cellular inhibition of the apoptotic protein (cIAP)-2 and Bcl-2 expression. We further found that UA decreased senescence-associated beta-galactosidase activity. We suggest that UA is a natural antioxidant and one of the functional modulators of hypoxia-induced survival, apoptosis, proliferation, and aging in mouse ES cells.

• Microbiology and Biotechnology Letters
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• v.35 no.3
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• pp.203-209
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• 2007

Soybean milk cake (SMC) was used for the solid-state fermentation by Bacillus subtilis PUL-A isolated from soybean milk cake. In the presence of 5% glutamate the maximum production of biopolymer (59.9 g/kg) was performed by fermentation at $42^{\circ}C$ for 24 hr. The recovered biopolymer was consisted of 87% $\gamma$-polyglutamic acid with molecular weight of $1.3{\times}10^6$ dalton and other biopolymer. The biopolymer solution showed the great decrease in consistency below pH 6.0, regardless of the molecular weight of PGA. Biopolymer solution has a typical pseudoplastic flow behavior and yield stress. The consistency of biopolymer solution was greatly decreased by increasing heating time and temperature in acidic condition compared to the alkaline condition. In kaolin clay suspension, the flocculating activity of biopolymer was the highest value with 15 mg/L biopolymer and 4.5 mM $CaCl_2$, but decreased greatly with $FeCl_3$. The flocculating activity of biopolymer was maximum at pH5, but decreased drastically by heating at $60{\sim}100^{\circ}C$. In particular, biopolymer with native PGA showed the efficient flocculating activity compared to that of modified biopolymer containing low molecular weight of PGA.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.6
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• pp.126-134
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• 2015

A sleep disorder is being recognized as one of the major health issues related to high levels of stress. At the same time, interests about quality of sleep are rapidly increasing. However, diagnosing sleep disorder is not a simple task because patients should undergo polysomnography test, which requires a long time and high cost. To solve this problem, an accelerometer embedded wrist-worn device is being considered as a simple and low cost solution. However, conventional methods determine a state of user to "sleep" or "wake" according to whether values of individual section's accelerometer data exceed a certain threshold or not. As a result, a high miss-classification rate is observed due to user's intermittent movements while sleeping and tiny movements while awake. In this paper, we propose a novel method that resolves the above problems by employing a dynamic classifier which evaluates a similarity between the neighboring data scores obtained from SVM classifier. A performance of the proposed method is evaluated using 50 data sets and its superiority is verified by achieving 88.9% accuracy, 88.9% sensitivity, and 88.5% specificity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.483-493
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• 2013

The high strength materials have been more widely used in a large reinforced concrete structures. It is known that the use of high strength material in RC structures give the benefits of the mechanical and durable properties, but the ductility decreases with an increase in the strength of the materials. In the design of a reinforced concrete beam, both the flexural strength and ductility need to be considered. So, it is necessary to assess accurately the ductility of the beam with high strength materials in order to ensure the ductility requirement in design. In this study, the effects of the material strength on the flexural behavior and curvature ductility factor of reinforcement concrete beam sections with various reinforcement conditions have been evaluated and a newly prediction formula for curvature ductility factor of RC beam has been developed considering the stress of compression reinforcement at ultimate state. The proposed predictions for the curvature ductility factor which is applicable to both singly and doubly reinforced concrete beam are verified by comparisons with other prediction formulas and the proposed formula offers fairly accurate within 9% error and consistent predictions for curvature ductility factor of reinforced concrete beam.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.425-431
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• 2015

LNG (liquefied natural gas) is considered the best alternative eco-fuel, and many studies on the LNG fuel system have been performed to use LNG as the fuel for ships. For the LNG fuel supply system, natural gas transfers from the vaporizer to the engine in the gaseous state with a temperature of $50^{\circ}C$ and a pressure of 35MPa. Therefore, a structural safety evaluation of the double-walled pipelines considering thermal load is essential. In this article, an uniaxial tensile test for super duplex stainless steel, material for double-walled pipe, according to the annealing time was carried out to analyze the thermal effect. In addition, thermo-structural analysis of the high temperature-high pressure double-walled pipe with fixed supports that are now used widely was carried out to evaluate the structural safety. To minimize stress concentration of the connection point between the support and inner pipe, the shapes of the new type support that can slip through inner pipe were proposed, and the supports which has best structural performance was selected using the results from the thermo-structural analyses of new supports and an analysis of the whole double-walled pipeline was performed to ensure structural safety. These results can be used as a database for the design of double-walled pipelines and sliding support.

• Journal of Acupuncture Research
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• v.27 no.1
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• pp.87-100
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• 2010

Background : Recently a discussion about Qi including a study about the effect or the theory of acupuncture is getting prevailing in various angles. In most of studies about acupuncture stimulus, 'Filiform acupuncture'(毫鍼) is used. A study about Nine kinds of acupuncture(九鍼), except 'Filiform acupuncture'(毫鍼) has not been reported yet, and there is no study about using a special acupuncture made for controling Qi either. Objectives : 'Dong Chu Gold Chim(DCG-chim, 東樞金鍼)' can be used for patients who are scared of a pain because it is a medical Qi-gong tool and non-invasive stimulus one. To assess a effect of Qi-gong operation using DCG-chim objectively Methods : The present study was performed to elucidate the effects of DCG-chim stimulation of an acupuncture point Baihui($GV_{20}$) on the Electroencephalogram(EEG). Twenty healthy subject were treated with DCG-chim one time accompanied by the light and vertical pressure and EEG were measured during five minutes for three times (before, during and after treatment). The EEG results of DCG-chim treatment were compared with those of 'Filiform acupuncture(毫鍼)'. Results : EEG power spectra changed significantly after both kind of acupuncture stimulation. Significant increase of $\alpha$ wave and decrease of $\beta$ wave were observed but interestingly, Mid-$\beta$ and SMR of $\beta$ wave which mean the state of concentration were increased with statistically significant. According to these results, DCG-chim stimulation of Baihui($GV_{20}$) seems to lead to relaxation with antianxietic effect and improvement of concentration at the same time. Conclusions : It would be expected that the doctor can apply DCG-chim for treating anxiety, tension, symptom caused by stress and also can use it clinically for patients who have needlphopia or children as a non-invasive procedure. It is suggested that additional studies about the effect of DCG-chim on other acupuncture points and comparison study about the effect of DCG-chim with those of the finger-pressure treatment using other tool should be done in the future.

• The Research Journal of the Costume Culture
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• v.6 no.3
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• pp.185-200
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• 1998

The eldest son of the crown prince is very important social status next to the crown prince deciding fundamentals of a state in Chosun dynasty which laying stress royal authority. Accordingly, Chakbong(冊封) of the eldest son of the crown prince has been done independently like as Chakrei(冊禮) of the crown prince. The existig record of Chakrei(冊禮) of the eldest son of the crown prince. The existing record of Charkrei(冊禮) of the eldest son of the crown prince are Hyunjongwangseon(顯宗王世孫), Euisoseson(懿昭世孫), Youngjowangseson(英祖王世孫), Hungjongwangseson(憲宗王世孫) of 4 books for Chakreidogameuigue(冊禮都監儀軌) being preserved in Kyujangkak(奎章閣). The transition of classified clothes are stated on Wangse sonchakreidogameuiguebanchado(王世孫冊禮都監儀軌班次圖) for Chakrei(冊禮) of the eldest son of the crown prince. Its details are as below. Finally, there is no changes in constitution of the costume of the eldest son of the crown prince Chakrei(冊禮) called as Ssanggodong(雙童髮)·Gongjungchak(空頂 )·Ojangbok(五章服) on documentary records depsitefo no explanation of Banchado(班次圖). Secondly, The classified clothes of the eldes sion of the crown prince Hcakreibanchado(冊禮班次圖) are on . We have acknowledged that Kwanmo(冠帽) of Dangbukwanwon(堂部官院) has been changed from Heugrib(黑笠) to Samo(紗帽) since Youngjowangseson(英祖王世孫), Euibok(衣服) from Chungpo(靑袍) to Nokdanryung(綠團領), the costume of Euijangsu(儀仗手) from Chunggun(靑巾) to Whangchorib(黃草笠) and changed again to Hongpimoja(紅皮帽子), Chungeui(靑衣) changed to Hongeui(紅衣). Also we know that Kwanmo(冠帽) of Kyogun(轎軍) has been changed to Pimoja(皮帽子) with high top, Chungeui(靑衣) changed to Hongeui(紅衣). The costume of Byulgam(別監) has been changed from Nokgun(綠巾) to Jogun( 巾), Nokpo(綠袍) changed to Pimoja(皮帽子) with high top, Chungeui(靑衣) changed to Hongeui(紅衣). The costume of Byulgam(別監) has been changed from Nokgun(綠巾) to Jogun( 巾), Nokpo(綠袍) changed to Hongpo(紅袍), that of Suri(書吏) changed from Chungeui(靑衣) to Huekeui(黑衣). Accordingly, the transition of costume color to red stands for the briliance. Thirdly, regarding the constitution of the eldest son of the crown prince Chakrei(冊禮), that of Euisoseson(懿昭世孫) & Youngjowangseson(英祖王世孫) are same for Unggolta(態骨朶), Youngjagi(令字旗), Keumdungja(金 子), Eundungja(銀 子), Mojul( 節), Jaksun(雀扇), Chungkae(靑蓋), Chungyangsol(靑陽率). In case of Hunjongseson(懿昭世孫), Baktakgi(白澤旗) is added. On Youngjowangseson(英祖王世孫), Chungilsol(靑日率) and Kiringi(麒麟旗) are added. However, we know that the constitution of the eldestson of the crown prince Hunjong(憲宗) Chakrei(冊禮) is quite different that of previous constitution. i.e. : Hongae(紅蓋), Baktakgi(白澤旗), Samkaggi(三角旗), Kagdangi(角端旗), Byukbonggi(碧鳳旗), Jujakgi(朱雀旗), Kuemdungja(金 子), Eundungja(銀 子), Eunribgwa(銀立瓜), Kuemhwanggwa(金 瓜), Eunhwhanggwa(銀 瓜), Kuemwolbu(金鉞斧), Bongsun(鳳扇), Huegkae(黑蓋). Also the kinds of Eujanggi(儀仗旗) are various which are similar to the constitution of The Crown Prince(世子) Chakrei(冊禮).

• Korea Journal of Hospital Management
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• v.9 no.4
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• pp.87-100
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• 2004

The main objective of this paper is to investigate the burnout state, coping types, and their relationship with organizational citizenship behavior, and based on the investigation, to provide some reference materials for effective management of burnout and appropriate methods of coping. For this purpose, employees of Korean Red Cross Blood Center were selected as the subject of the research. Data for empirical analysis were obtained through mail survey using structured and self-administered questionnaire for 282 employees of five Red Cross Blood Centers across the nation. Following is the summary of the results: 1) Degree of organizational citizenship behavior was higher among the married, the forties in age, and the employees whose major reason for choosing to work at the Center was 'to help other people.' On the other hand, degree of burnout was higher among the single but lower among the forties in age and the employees who chose to work at the Center because of suitable abilities and interests. As for the types of coping, problem-oriented coping method was more frequently used by the married, older, relatively more-educated and higher-grade employees. 2) Among the three kinds of burnout, 'achievement burnout' was found to have the greatest influence on the organizational citizenship behavior, negatively affecting organizational citizenship behavior as a whole and all of its components except for 'sportsmanship.' Next was 'impersonality burnout,' which also had negative effect on organizational citizenship behavior as a whole, and altruism, conscientiousness and sportsmanship among the components. Finally, 'emotion burnout' appeared to have positive effect on altruism and courtesy but negative effect on sportsmanship. 3) Among the various types of coping, 'problem-oriented' and 'positive perspective' coping methods were found to positively influence overall organizational citizenship behavior, whereas 'stress dissolution' had negative effect. These results imply that special management, counselling and education are needed for sociodemographic groups with high burnout to utilize problem-oriented and positive perspective coping methods which are considered to have desirable effects in coping with burnout problems. In addition, some methods should be devised to prevent and manage the 'achievement burnout' that was found to have great negative influence on organizational citizenship behavior.