• Korean Journal of Optics and Photonics
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• v.24 no.5
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• pp.217-223
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• 2013

White light MTF(Modulation Transter Function)s of biconvex trial lenses from 10 to 20 diopter (D) were represented as a function of angular frequency and visual acuity, and then they were compared with AIM(Aerial Image Modulation) curves. All of the biconvex trial lenses evaluated in on-axis mode had MTF performance that could resolve Landolt's ring up to visual acuity 2.0. However, in a half field angle of five degrees, the trial lens of 10 diopters was able to resolve Landolt's ring up to visual acuity 0.9, and that of 20 diopter only up to visual acuity 0.8. This means that the trial lenses in the case of a half field angle of five degrees do not have sufficient resolution to measure visual acuity by 1.0.

• The Journal of the Convergence on Culture Technology
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• v.4 no.1
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• pp.315-323
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• 2018

Rapid increase of diabetic population is a major health concern in Korea. In a trial to develop food components which can prevent and/or cure diabetes, we investigated the anti-diabetic activity of curcumin in high fat diet (HFD)-induced type 2 diabetes mellitus (T2DM) animal model. C57BL/6 mice were divided into three groups: normal diet (ND), high fat diet (HFD), and curcumin (CUR, HFD+0.02% curcumin). Mice were fed each diet for 16 weeks. CUR significantly reduced body weight gain, the levels of plasma glucose, insulin, total-cholesterol (T-C), and LDL-C, whereas increased HDL-C compared to those of HFD group. Notably, insulin signaling pathway was activated by CUR. This suggests that CUR improves obesity-associated T2DM by overcoming insulin resistance in part.

• Korean Journal of Social Welfare
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• v.68 no.3
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• pp.181-201
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• 2016

Using a nationally representative sample from three recent waves of the Korean Welfare Panel Study, this study examined the association between experiencing material hardship and suicidal ideation among low-income households in South Korea. Overall, we found that experiencing material hardship was associated with a higher likelihood of having suicidal ideation. We also found that, among individual items of material hardship, experiencing food insecurity or credit problems was associated with a higher likelihood of having suicidal ideation. Furthermore, we found that the association of experiencing material hardship with having suicidal ideation was more pronounced for male-headed or elderly-headed households. Policy implications to improve living condition among low-income households and reduce their suicide-related behavior were discussed.

• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.14-18
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• 2010

Rosmarinic acid, an ester of caffeic acid with 3,4-dihydroxyphenyl lactic acid, is one of the main active constituents of Agastache rugosa Kuntze and has an astringent property, antioxidant capacity, anti-inflammatory activity, antimutagenic ability, antimicrobial capacity, and an antiviral property. Five different strains of Agrobacterium rhizogenes differed in their ability to induce Korean mint (Agastache rugosa Kuntze) hairy roots and also showed varying effects on the growth and rosmarinic acid production in hairy root cultures. A. rhizogenes R1601 is the most effective strain for the induction (72.90%), growth (13.50 g/l) and rosmarinic acid production (22.60 mg/g) in hairy root of Korean mint. Our results demonstrate that use of suitable strains of A. rhizogenes may allow study of the regulation of rosmarinic acid biosynthesis in hairy root cultures of Agastache rugosa.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1243-1249
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• 2006

Volatile flavor compounds in commercial crab-like flavorants were compared by mean of solid phase microextraction(SPME) and liquid continuous extraction (LLCE)/GC/MSD methods. A total of 86 volatile flavor compounds were detected. Of these, 71 were positively identified consisting mainly of sulfur-containing compounds (13), aldehydes (3), ketones (2), esters (26), alcohols (5), aromatic compounds (3), terpenes (8), acids (2) and miscellaneous compounds (9). SPME method was more effective than LLCE method in detection of volatile components in commercial crab-like flavorants. Eight S-, N-containing compounds such as dimethyl sulfide, dimethyl disulfide, dipropyl disulfide, 3-(methylthio)propyl acetate, 3-(methylthio) propanal, 3-(methylthio) propanol, 2-methyl-3-(methylthio) pyrazine and 2-methyl-5-(methylthio) pyrazine, 8 esters such as styrallyl acetate, ethyl acetate, isoamyl acetate, benzyl acetate, ethyl pentanoate, butyl pentanoate, isoamyl pentanoate and furfuryl acetate were considered as major components in crab-like flavorants.

• Journal of the Korean Data and Information Science Society
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• v.22 no.6
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• pp.1065-1074
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• 2011

During several decades, many researchers in the field of finance have studied Value at Risk (VaR) to measure the market risk. VaR indicates the worst loss over a target horizon such that there is a low, pre-specified probability that the actual loss will be larger (Jorion, 2006, p.106). In this paper, we compare conditional copula method with two conventional VaR forecasting methods based on simple moving average and exponentially weighted moving average for measuring the risk of the portfolio, consisting of two domestic stock indices. Through real data analysis, we conclude that the conditional copula method can improve the accuracy of portfolio VaR forecasting in the presence of high kurtosis and strong correlation in the data.

• Polymer(Korea)
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• v.29 no.5
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• pp.481-485
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• 2005

In this work, the thermal and mechanical properties of vapor grown carbon nanofibers (VGCNFs)-reinforced difunctional epoxy (EP) composites were investigated in the presence of the 0, 0.1, 0.5, 1.0, and $2wt\%$ VGCNFs. The thermal properties of the VGCNFs/EP composites were studied by thermo-mechanical analysis (TMA) and dynamic mechanical analysis (DMA). The mechanical properties of the VGCNFs/EP composites were also examined by universal testing machine (UTM), falling impact test, and the friction and wear tests. From experimental results, the thermal and mechanical properties of the VGCNFs/EP composites were improved with increasing the VGCNFs contents. This was due to the increase of crosslinking structure of the composites, resulting in improving the mechanical interlockings between VGCNFs and epoxy resins in the present composite system.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1174-1179
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• 2006

In order to study auricular acupuncture and treadmill exercise involved in high fat diet-induced obesity rats. Thirty Sprague-Dawley rats which were divided into five group. Group I : Normal diet-induced group, Group II : high fat diet-induced group, Group III: high fat diet-induced group and auricular acupuncture, Group IV : high fat diet-induced group and treadmill exercise, Group V : high fat diet-induced group and auricular acupuncture and treadmill exercise. In each group, body weight, serum lipid, histologic obserations, and fat tissue were observed and analyzed. The following results were obtained. Body weights were significantly increase in group II than group I. The level of total cholesterol, LDL-C and TG were significantly lower in experimental groups than group I. Only auricular acupuncture was tended to body weight change but not significantly different between experimental group. The above result suggest that auricular acupuncture and treadmill exercise effectively repressed in obesity. It would be considered that auricular acupuncture and treadmill exercise have an effects on relieving obesity.

• Food Industry And Nutrition
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• v.10 no.3
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• pp.37-42
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• 2005

홍경천의 간보호 효과를 알아보고자 사염화탄소를 투여하여 간손상을 유발시킨 흰쥐에 홍경천 물추출물을 투여한 후 간독성 보호효과를 알아본 결과, 혈청중 ALT, AST, LDH, ALP 활성도는 사염화탄소 투여에 의해 증가하였으나, 사염화탄소 투여 후 홍경천 물추출물의 투여로 유의적인 감소를 나타내었다. Total cholesterol, total lipid, triglyceride는 사염화탄소 투여에 의해 증가하였으나, 사염화탄소 투여 후 홍경천 물추출물의 투여로 유의적인 감소를 나타내었다. 한편 phospholipid는 사염화탄소만 투여한 CCL군과 사염화탄소 투여 후 홍경천 물추출물을 투여 한 군 모두 유의성 차이는 없었으나 홍경천 물추출물을 투여함으로 증가함을 알 수 있었다. HDL-cholesterol의 함량은 사염화탄소만 투여한 CCL군에 비해 사염화탄소 투여 후 홍경천 물추출물을 투여 한 RSLIII군에서 유의적으로 높은 수치를 보였다. LDL-cholesterol은 사염화탄소만 투여 한 군과 사염화탄소를 투여후 홍경천 물추출물을 투여한 군간 유의적 차이를 확인할 수 없었다 이상의 결과에서 사염화탄소 투여로 각종 효소 활성도 및 지질의 함량이 증가되었는데 이는 사염화탄소 투여로 간세포에 손상이 유발되었음을 알 수 있었고, 사염화탄소 투여 후 홍경천 물추출물을 투여한 군에서 사염화탄소 투여로 증가된 각종 효소 활성도 및 각종 지질의 함량을 저하시키므로서 홍경천 물추출물이 손상된 간기능을 회복시킬 수 있을 것으로 사료된다.

• The Journal of Korean Medicine
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• v.42 no.1
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• pp.75-98
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• 2021

Objectives: The purpose of this study is to investigate the characteristics, validity, and reliability of non-radiological assessment tools of scoliosis that have been studied so far. Methods: Electronic databases including Pubmed, Cochrane Library, CNKI, Science On, RISS, OASIS were searched by keywords including 'scoliosis assessment', 'scoliosis screening', 'physical examination', 'functional measurement', 'photography', and 'smartphone'. Results: 32 articles using radiation-free assessments were identified from 1,011 records. The mostly used non-radiological methods were Surface topography, Scoliometer, Ultrasound, Digital Infrared Thermal Imaging, and Photography. The other methods were Gait analysis, 3D depth sensor imaging, and Low intensity electromagnetic scan. Conclusions: It was found that non-radiological assessment tools might reduce the number of radiographs taken in scoliosis patients. To increase the reliability and validity, further research on the measurement tools of scoliosis will be needed.