• 한국환경보건학회지
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• 제22권2호
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• pp.124-129
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• 1996

In order to investigate the deposition chara.cteristics of water-soluble ionic components in dustfall in Kwangju city, dustfall samples were collected by deposit jar for one year from December 1992 to November 1993. The depositjon amount of dustfall and water-soluble ionic components ($SO_4^{2-}, NO_3^-, Cl^-, NH_4^+, Na^+, Ca^{2+}, Mg^{2+}, K^+$) were measured. The total deposition amount of dustfall was 10.0 ton/$km^2$/month and showed seasonal trend of Summer and Spring > Fall and Winter. The total deposition amounts of water-soluble components showed 2.41 ton/$km^2$/month and seasonal trend of Summer > Fall > Spring > Winter. Deposition amount of $SO_4^{2-}$ was 0.99 ton/$km^2$/month which makes up 41% of water-soluble components. The deposition amounts of dustfall and watersoluble components according to the sampling points were approximately similar to each other. From this result, it can be estimated that the deposition amounts of dustfall and water-soluble components in dustfall were more influenced by the seasonal variation than the regional emission characteristics of pollution source. The content of each ionic component to the deposition amount of water-soluble components showed in order of $SO_4^{2-} > Cl^- > NH_4^+ > Na^+ > Ca^{2+} = K^+ > NO_3^- > Mg^{2+}$ respectively.

• 한국환경복원기술학회지
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• 제9권4호
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• pp.52-59
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• 2006

This study was conducted to find end-members and tracers which are effective to be applied in the End Member Mixing Analysis (EMMA) model for runoff separation at the Gwangneung coniferous forest catchment (13.6ha), Gyeonggido, Korea. We monitored three successive rainfall events during two weeks from June 26, 2005 to July 10, 2005, and analysed chemical properties of rainfall, throughfall, stemflow, groundwater and soil water considered as main components of storm runoff. The followings are the results of analyses of each component and tracer. Groundwater, soil water and rainfall (or throughfall) were dominant runoff components. Rainfall and groundwater were selected as main components for the two components-one tracer mixing model, and groundwater, soilwater and throughfall were selected as main components for the three components-two tracers mixing model. Tracers were selected from anion ($Cl^-$ and ${SO_4}^{2-}$), cation ($Na^+$, $K^+$, $Mg^{2+}$, and $Ca^{2+}$) and Acid Neutralizing Capacity (ANC) in event 1, 2, and 3. $Na^+$, $Ca^{2+}$ and ANC were selected in the two components-one tracer mixing model and ${SO_4}^{2-}-K^+$, ${SO_4}^{2-}-Na^+$, ${SO_4}^{2-}-Ca^{2+}$, ${SO_4}^{2-}$-ANC, and $Ca^{2+}$-ANC were selected in the three components-two tracers mixing model. Selected main runoff components and tracers can provide basic information to determine the contribution rate of each runoff component and identify the runoff process in a forest watershed.

• 한국산림과학회지
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• 제108권1호
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• pp.21-28
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• 2019

This study was conducted to determine the carbon (C) and nitrogen (N) response of litterfall components as affected by N addition in compound fertilizer in a Korean red pine (Pinus densiflora S. et Z.) stand in southern Korea. Litterfall in a mature red pine stand was collected for two years following compound fertilizer application ($N_3P_4K_1$; $P_4K_1$) and no fertilization (control). The C concentration of litterfall components was not significantly (P > 0.05) different between the $N_3P_4K_1$ and the control plots, whereas the N concentration of the litterfall components was significantly higher in the $N_3P_4K_1$ plot than in the control plot. The $N_3P_4K_1$ and $P_4K_1$ additions induced a lower C/N ratio of litterfall components compared with the control plot. Annual C and N fluxes via litterfall components were not affected by the $N_3P_4K_1$ addition over the study period, except for reproduction litter. Annual N fluxes via reproduction litter were significantly higher in the $N_3P_4K_1$ plot than in the control plot. Thus, the $N_3P_4K_1$ and $P_4K_1$ additions could modify differently nutrient distribution of the forest floor and mineral soils in a red pine stand. These results indicate that N concentration and C/N ratio in litterfall components are more susceptible to fertilizer application than the C response in litterfall components.

• ETRI Journal
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• 제29권4호
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• pp.452-456
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• 2007

Very compact 4-channel 200-GHz-spacing external cavity lasers (ECLs) were fabricated by hybrid integration of reflection gratings and superluminescent laser diodes on a planar lightwave circuit chip. The fifth-order gratings as reflection gratings were formed using a conventional contact-mask photo-lithography process to achieve low-cost fabrication. The lasing wavelength of the fabricated ECLs matched the ITU grid with an accuracy of ${\pm}0.1$ nm, and optical powers were more than 0.4 mW at the injection current of 80 mA for all channels. The ECLs showed single mode operations with more than 30 dB side lobe suppression.

• 복식문화연구
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• 제28권6호
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• pp.801-814
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• 2020

The purpose of this study was to explore the importance level, the present level, and the educational need for 21 business ethics components among 2-year and 4-year college students majoring in fashion. Survey data of 364 students (128 students of 2-year colleges and 238 students of 4-year colleges) were analyzed through descriptive statistics, Borich's needs assessment for education, The Locus for Focus model, exploratory factor analysis, and t-test. The results showed five business ethics components ranked highly as educational needs among college students: 'reducing waste', 'using vegan materials', 'using human-friendly materials', 'strengthening sustainable technologies', and 'promoting workers' rights'. Those components should be integrated into curricula of fashion majors in colleges. Students in 4-year colleges considered most of 21 business ethics components as more important than did students at 2-year colleges. More needs for education were observed by 4-year college students in eight business ethics components than by 2-year college students. In addition, a positive attitude toward business ethics education and the suitability of business ethics education were higher among 4-year college students than 2-year college students. Results provide a guideline for business ethics education by indicating a list of business ethics components that urgently needed to be adapted to fashion curricula according to each college type.

• 환경위생공학
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• 제14권3호
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• pp.139-149
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• 1999

This study was performed to investigate components of organic solvents and present statues of environmental measurements with official records of working environmental measurements of 4,181 workplaces in 3,280 workshops used airborne organic solvents. 1. The mean working hour of 4,181 workplace producing airborne organic solvents in 3,280 workshops was 437±28.7min, but the mean sampling time for measurement of airborne organic solvents was identified to be 254±28.8min. In 73.0% of 4,181 samples the sampling frequencys were Full-period, single sample measurement. 2. The total 54 components of organic solvents were measured in total airborne samples of 4,181 workplace in 3,280 workshops in both of first and second half-year. These were divided into 38 components, Group 1 substances (5 components), Group 2 substances (31 components) and Group 3 substances (2 components), regulated by the Industrial Safety and Health Law, and other 16 components without legal duty of working environment measurement. The most common component in each half-year was Toluene (84.8%, 88.2%), which was followed by Xylene (464.4%, 51.7%), Methyl ethyl ketone (31.1%, 34.4%), n-Hexane (22.7%, 27.8%) and Benzene (20.4%, 21.5%) in frequency. Of legal duty free components, Ethyl benzen, Trimethyl benzene and Pentane were frequently detected. In conclusion, these results show that the present legal classification system of organic solvents needs to revise. Also these results suggest that it must be necessary to analyze the component of airborne organic solvents mixture and to evaluate their effects on workers' health for the effective management of working environment in workshops treating with organic solvents.

• 한국식품과학회지
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• 제26권4호
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• pp.359-364
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• 1994

야생식용식물인 메꽃의 식용부위에 따른 휘발성 풍미성분을 분석하기 위하여 SDE방법으로 정유성분을 분리한 다음 GC 및 GC-MS를 이용하여 성분을 확인하였다. 잎에서는 탄화수소류 21종, 알데히드류 1종, 케톤류 4종, 알콜류 7종, 에스테르류 4종, 유기산류 1종 및 기타 1종이 확인되었다. 줄기에서는 탄화수소류 16종, 알데히드류 2종, 케톤류 3종 및 알콜류 5종이 확인되었으며, 뿌리에서는 탄화수소류 26종, 알데히드류 2종, 케톤류 5종, 알콜류 13종, 에스테르류 1종, 유기산류 1종 및 기타 4종이 확인되었다. 잎과 중기에서보다 뿌리에서 확인된 휘발성 풍미성분의 종류가 더 다양하였고 잎과 줄기는 탄화수소류가 다량 함유된 반면 뿌리에는 신선한 풀내음과 달콤한 향을 부여하는 알데히드류, 케톤류 및 알콜류가 다른 부위보다 수(數)적으로나 양(量)적으로 다량 함유되어 있었다.

• ETRI Journal
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• 제33권6호
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• pp.969-972
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• 2011

This letter presents a CMOS RF front-end operating in a subthreshold region for low-power Band-III mobile TV applications. The performance and feasibility of the RF front-end are verified by integrating with a low-IF RF tuner fabricated in a 0.13-${\mu}m$ CMOS technology. The RF front-end achieves the measured noise figure of 4.4 dB and a wide gain control range of 68.7 dB with a maximum gain of 54.7 dB. The power consumption of the RF front-end is 13.8 mW from a 1.2 V supply.

• 한국식품과학회지
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• 제27권4호
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• pp.464-470
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• 1995

야생식용식물인 닭의장풀의 식용부위에 따른 휘발성 향기성분을 분석하기 위해 SDE방법으로 정유성분을 추출한 다음 GC 및 GC-MS를 이용하여 성분을 확인하였다. 전초에서는 탄화수소류 33종 알데히드류 4종, 케톤류 9종, 알코올류 23종, 에스테르류 6종, 유기산류 10종 및 기타 4종이 확인되었고, 잎에서는 탄화수소류 14종 및 알코올류 7종및 에스테르류 2종, 주기에서는 탄화수소류 3종 및 알코올류 3종, 뿌리에서는 탄화수소류 13종, 케톤류 1종, 알코올류 3종 및 유기산류 1종이 확인되었다. 닭의장풀 잎의 경우 줄기 및 뿌리부위보다 탄화수소류가 차지하는 비율이 높았고 다른 부위보다 알코올류의 함량은 적었으나 그 수는 더욱 다양하였다. 줄기 부위는 다른 부위에 비하여 가장 적은 수의 휘발성 향기성분이 확인되었으나 알코올류가 차지하는 비율은 월등히 높았다.

• 한국지역사회생활과학회지
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• 제16권4호
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• pp.15-24
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• 2005

We investigated the changes of volatile flavor components from Codonopsis lanceolata, which were packed in woven polypropylene(WP) film or low density polyethylene(LDPE) film and stored for 15 and 30 days at refrigerated($2{\∼}4^{\circ}C$ ) or room($18{\∼}20^{\circ}C$) temperature. A hundred and sixty seven volatile flavor components in the fresh C. lanceolata were identified by GC/MS analysis. When determining the flavor components from C. lanceolata cultivated on a wild hill and stored at 4 conditions for 30days, six volatile components such as 1-hexadecene, 2,6-dimethyl-2-octanol, 2-methyl-2-dodecanol, $\alpha$-guaiene, $\delta$-cadinene and trans-2-hexen-1-ol were detected as common components of all stored samples, and The types of common flavor components of C. lanceolata were different according to storage conditions. The numbers were 16 from refrigerated, 7 from room temperature stored, and 10 components from WP or LDPE packed conditions, respectively. The total peak area ratio of the major 10 compounds were $52.0{\∼}86.8\%$, and the percentage of trans-2-hexen-1-ol, which was the only common compound among the major 10 components, was the highest as $26.4{\∼}68.1\%$ The major flavor profile, describe by highly trained panel, were green, aldehydic, earthy and camphoreous. As the result from sensory evaluation, the freshness of C. lanceolata was maintained better by controlling storage temperature rather than selection of package materials. The best condition for characteristic flavor of C. lanceolata was packing with LDPE and chilling.