• 대한수학회논문집
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• 제37권2호
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• pp.385-397
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• 2022

Let (M, [ , ]) be a finite dimensional Malcev algebra over an algebraically closed field 𝔽 of characteristic 0. We first prove that, (M, [ , ]) (with [M, M] ≠ 0) is simple if and only if ind(M) = 1 (i.e., M admits a unique (up to a scalar multiple) invariant scalar product). Further, we characterize the form of skew-symmetric biderivations on simple Malcev algebras. In particular, we prove that the simple seven dimensional non-Lie Malcev algebra has no nontrivial skew-symmetric biderivation.

• 한국산업융합학회 논문집
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• 제5권3호
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• pp.201-208
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• 2002

The machine tool which operates by hand is replacing by CNC machine tool to improve the quality of the product and the productivity in modem mechanic industry. The precision of machine part is influenced greatly the surface roughness by cutting condition of machine tool. So this study was performed to examine the aluminium surface roughness of section according to change of strength rating, nose radius, cutting speed, using live center. The results of this study are as follows; 1. In the case of 56mm diameter of test piece(length is below triple of diameter), whether establish the live center or not, doesn't influence to the surface roughness, and it is possible to make product without the live center. 2. The average surface roughness of 42mm diameter(length is quadruple of diameter) is similar to the 56mm diameter in the cutting condition of nose radius 0.8mm and cutting speed 140mm/min, but there are increases and differences in other cutting conditions. 3. In the case of test piece length more 70m/min(140m/mm) and nose radius improved greatly using the live center. 4. In the case of test piece length is quintuple of diameter, the nose radius must choose big tool and increase the cutting speed in preference live center establishment availability to improve that is surface roughness. Conclusively, if aluminum test piece length is fewer than triple of diameter, can process without establishing live center. If aluminum test piece length is more than quintuple of diameter, cutting conditions to improve surface roughness are (1) cutting speed (2) nose radius (3) whether the live center uses or not.

• Mass Spectrometry Letters
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• 제10권2호
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• pp.61-65
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• 2019

Korean ginseng (Panax ginseng Meyer) is a traditional herb used across the world to treat various diseases. Although, red ginseng is this herb's most famous product and has demonstrated diverse pharmacological activities, white ginseng (WG) is another ginseng product that is made fresh and individually regulated in Eastern Asia. Red and white ginseng show different characteristics due to distinct processing steps despite originating from the same plant, and the drug interactions induced by WG have not been well documented. Selegiline is a selective monoamine oxidase (MAO) inhibitor used as an antidyskinetic and antiparkinsonian agent. Here we developed a quantification method for selegiline in mouse plasma using a C8 stationary phase in triple quadrupole-mass spectrometry (LC-MS/MS) with multiple reaction monitoring (MRM). The validated LC-MS/MS method was successfully applied to determine the potential interaction with WG extract (0.1 g/kg/day) pre-administered for 4 weeks. The $AUC_{0-240min}$ of selegiline was altered due to a decrease in the absorption of selegiline with repeated administration of WG extract.

• 패션비즈니스
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• 제21권1호
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• pp.45-57
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• 2017

This study explored the current implementation status of corporate social responsibility (CSR) among textiles and apparel manufacturers and retailers in Korea, based on the Triple Bottom Line (TBL). We also investigated the provision of information related to CSR practices on the websites of companies. A quantitative content analysis was conducted to analyze the website disclosures of 61 listed companies categorized in the textiles, apparel, shoes, and luxury industry. Analysis was focused on the presence, accessibility, and the level of CSR website disclosure. Seven themes emerged by applying the constant comparison analysis. Using Scott's formula for pi, a high level of inter-coder reliability was achieved, ranging from 0.91 to 0.97. Regarding the three dimensions of CSR suggested in TBL, economic dimension was relatively more emphasized in the website disclosures of most companies, compared to social and environment dimensions. Website disclosures were further investigated, based on the product categories of each company. Limitations of this study and suggestions for future studies are discussed.

• 대한기계학회논문집
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• 제19권3호
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• pp.846-857
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• 1995

An experimental study is made of turbulent shear flows in a nearly two-dimensional 90.deg. curved duct by using the hot-wire anemometer. The Reynolds normal and shear stresses, triple velocity products, integral length scales, Taylor micro length scales and dissipation length scales are measured and analyzed. For a positive shear at the inlet, the afore-mentioned turbulence quantities are all suppressed. However, when the inlet shear flow is negative, they are augmented, i.e., the convex curvature suppresses the turbulence whereas the concave curvature augments it. It is found that the curvature effects are rather sensitive to the triple velocity products than the Reynolds stresses. The evolution of turbulence under the curvature with the different shear conditions is well described by the modified curvature parameter S' and the non-dimensional development time ${\tau}$.'

• 대한기계학회논문집
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• 제9권4호
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• pp.403-413
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• 1985

본 논문에서는 수직벽 하류에 형성되는 박이 전단층의 발전과 재부착 그리고 재발전 경계층에 대해 평균 속도, 벽면의 압력 분포, 난류 강도, 레이놀즈 전단 압력 및 아직 수직벽에 대해서는 보고된바 없는 난류 떨림 속도 성분들의 3승곱 통계치를 측정하여 난류 구조의 변화를 분석하고 이를 수치적 계산 모델개발의 자 료로 제공하고자 함이 이 연구의 목적이다.

• 복식문화연구
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• 제27권1호
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• pp.64-71
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• 2019

Climate change and global warming are the biggest challenges of the current generation. Every industry has contributed to the climate change and global warming. Even the apparel industry cannot avoid the criticism regarding fast fashion and its contribution to the pollution. The transition to the decarbonized economy is in progress. All aspects of business functions are influenced by climate change. Sustainable development and climate change are closely linked, and business plays the key role in addressing and finding solutions to the challenges of climate change. Luxury brands are the trendsetters and tastemakers. They are the leaders in the fashion industry and therefore responsible for improving on sustainability as well. Even luxury business cannot avoid environmental issues. The relation between luxury and sustainability is explored with the Burberry case based on the Triple Bottom Line (TBL) framework. There are various ways for luxury brands to excel in sustainability and affect other companies' practices. The companies can incorporate the concept of sustainability in their brand stories as part of the branding process. They can also improve demand planning accuracy and produce upcycled goods. Centering on Burberry's case, this paper aims to explore the current sustainable practices of luxury business along with its future direction toward sustainable development. Its contribution and directions for both researchers and business practitioners are discussed.

• Bulletin of the Korean Chemical Society
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• 제28권7호
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• pp.1127-1134
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• 2007

It was demonstrated that Y[N(TMS)2]3, the neutral yttrium-diamine complex 13 and yttrium-NPS complexes 15 are efficient precatalysts for intramolecular hydroamination of aminoalkynes involving primary amines. Complex 13 and 15 were quantitatively prepared in situ by direct metalation of the ligands 4 and 9 with 1 equiv of Y[N(TMS)2]3 in benzene-d6 at 120 oC for 5 days and 10 days, respectively, via elimination of (TMS)2NH. 5-Exo- and 6-exo-dig intramolecular hydroamination of aminoalkynes using catalyst 12 and 13 proceeded smoothly to give nitrogen-contained cyclic products in good to excellent yields in all cases. In the case of 7- exo-dig intramolecular hydroamination, the desired product was produced in 41% and 48% yields despite the gem-dimethyl effect. However, treatment of catalyst 15 with aminoalkynes (19 and 22) having a methyl substituent at the carbon adjacent to triple bond and 6-exo-dig intramolecular hydroamination of 21 failed to give the desired products. Zirconium-catalyzed intramolecular hydroamination of aminoallenes (25, 27, and 31) with 5 mol% 16 afforded 2-(trans-1-propenyl)pyrrolidine, 2-isopropylenepyrrolidine, and 2-(trans-1- propenyl)piperidine in 96%, 95%, and 93% yield, respectively. However, subjecting 25 to 5 mol% 15 was unsuccessful to produce the desired product.

• 한국대기환경학회지
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• 제9권2호
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• pp.154-159
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• 1993

Theoretical prediction of the equilibrium of temperature and relative humidity dependance involving $HNO_{3(g)}-NH_{3(g)}$ and $NH_4NH_{3(s, aq)}$ was compared with atmospheric measurement of particulate nitrate$(NO_3^-)$, Ammonia-Nitric Acid partial pressure product $([$NH_{3(g)}][HNO_{3(g)}]ppb^2$) by a triple filter pack sampler from Oct 1991 to July 1992. The measured $HNO_3NH_3$ concentration product K was greater than equilibrium constant $K_p$ calculated from thermodynamic data of $NH_4NO_{3(s, aq)}-HNO_{3(g)}-NH_{3(g)}$ during fall, winter and spring. But K was lower than $K_p$ in summer. K was greater than $K_p$ as the result of supersaturation by air pollution, particularly anthropogenic $NH_3$.The reason of $K < K_p$ was due to removal of particulate nitrate$(NO_3^-)$ by rainout and washout. $NH_4NO_3$ which consists mainly of particulate nitrate is formed by reaction between $HNO_3$ and $NH_3$. As a result of the removal of particulate nitrate$(NO_3^-)$ by rainout and washout, concentrations of $HNO_3$ and $NH_3$ are decreased by equilibrium transfer(Le Chatelier's Law) in atmosphere.

• 대한간호학회지
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• 제53권2호
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• pp.155-166
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• 2023

Purpose: Although heated tobacco product (HTP) use among adolescents is an emerging public health problem, little is known about the frequency and quantity of HTP use. Thus, we investigated the associations between the frequency and quantity of HTP use and smoking characteristics (i.e., combustible cigarette [CC] and electronic cigarette [EC] use, and attempts to quit smoking) among CC-smoking adolescents. Methods: We analyzed nationally representative data from 2,470 Korean adolescents who were current CC smokers. To investigate our aim, we conducted multinomial logistic and logistic regression analyses. Results: We found that daily and heavier CC users had greater likelihoods of more frequent and heavier HTP use. In addition, dual users of CCs and ECs were more likely to use HTPs more frequently and heavily than CC users who did not use ECs. Moreover, daily EC users had the highest risk of frequent and heavy HTP use. The frequency and quantity of HTP use were not associated with attempts to quit smoking. Compared to CC-only use, dual use of CCs and HTPs was not associated with quitting attempts, and triple use of CCs, ECs, and HTPs was associated with a lower likelihood of quitting attempts. Conclusion: HTP use was less likely to displace CC use and promote attempts to quit smoking. Thus, strict regulations are required to prevent the promotion of HTPs as a substitute for CCs or as a means of quitting smoking. Additionally, health professionals should consider preventive interventions for HTP, as well as CC and EC use among adolescents.