• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.578-589
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• 2003

The fuzzy rat that expresses hypersecretion of sebum and hyperplastic sebaceous glands is a genetic mutant for the study of many pharmacological aspects especially human acne. Through this model, we examined the effects of several phospholipids on the secretion of sebum after topical application. The phospholipid derivatives were phosphatidylcholine (PC), hydrogenated phosphatidylcholine (HPC), phosphati dylserine (PS) and hydrogenated phosphatidylserine(HPS). All agents were dissolved into the vehicle (1, 3-Butanediol, ethanol and water) at 0.5％ weight volume and applied on the dorsal area of the fuzzy rat. To observe histological changes, the skin biopsies were stained with Oil Red O and the size and morphology of sebaceous gland was observed under microscope. Topical treatment with PC and/or HPC showed a marked decrease in sebum excretion. Especially hydrogenated PC (HPC) appeared to have more predominant sebosuppressive function than any other treatment. The other agents such as PS and HPS showed a marginal effect on sebum secretion. With the sebosuppressive activity, HPC and PC seem to have a good potential application on acne treatment. In order to obtain more insights into possible mechanisms behind the above observations, effects of each phospholipid on the expression of peroxisome proliferator-activated receptor (PPAR) genes were investigated. Recently, it has been demonstrated that expression and activation of PPAR subtypes appear to modulate the accumulation of cytoplasmic fat droplets that characterizes the sebocyte differentiation(1). It was also previously suggested that PPAR${\gamma}$ antagonist would seem possible to interfere sebum production without side effects (2). In this study we examined the diverse effects of the tested phospholipids on the expression of several PPAR genes based on reverse transcription-polymerase chain reaction (RT-PCR) from the topically treated skin of fuzzy rats. The results and possible implications are discussed.

• Applied Microscopy
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• v.52
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• pp.5.1-5.10
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• 2022

The use of Pipelines for long-distance transportation of crude oil, natural gas and similar applications is increasing and has pivotal importance in recent times. High specific strength plays a crucial role in improving transport efficiency through increased pressure and improved laying efficiency through reduced diameter and weight of line pipes. TRIP-based high-strength and high-ductility alloys comprise a mixture of ferrite, bainite, and retained austenite that provide excellent mechanical properties such as dimensional stability, fatigue strength, and impact toughness. This study performs microstructure analysis using both Nital etching and LePera etching methods. At the time of Nital etching, it is difficult to distinctly observe second phase. However, using LePera etching conditions it is possible to distinctly measure the M/A phase and ferrite matrix. The fraction measurement was done using OM and SEM images which give similar results for the average volume fraction of the phases. Although it is possible to distinguish the M/A phase from the SEM image of the sample subjected to LePera etching. However, using Nital etching is nearly impossible. Nital etching is good at specific phase analysis than LePera etching when using SEM images.

• Clean Technology
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• v.16 no.3
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• pp.229-237
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• 2010

The industrial ecology indicators(IEI) for Yeosu Industrial Park were developed using eco-efficiency indicator(EEI). The key factors for the creation of IEI were two parts. One part is the value of the products which is selected as the total production value, the amount of ethylene production, the amount of light oil production instead of the total sales volume for Yeosu Industrial Park, since the currency exchange and the price of raw materials varied every year. The other part is the environmental burden. The electric consumption, the industrial water consumption, and the amount of discharged waste water are all officially opened to the public, were used in the calculation. Based on the value for the year of 2004, the IEI value for 2006 became worse to 0.954, but, was expected to be 1.153, a 15% improvement, for 2015 if the current EIP project is successfully performed.

• Korea Trade Review
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• v.41 no.4
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• pp.221-243
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• 2016

This study examined the trade of the Central Asian CIS countries and the Daegu-Gyeongbuk region. These countries are rich in resources such as oil, natural gas and aluminum. These countries were switched to capitalist market economy after independence from the Soviet Union. So, these countries are considered as new emerging markets. This study analyzed the current status of trade between Daegu-Gyeongbuk region and Central Asian CIS countries. The result of analysis of the trade structure between the Daegu-Gyeongbuk and Central Asian CIS countries, and of the Daegu-Gyeongbuk region exports to Central Asian CIS countries showed insufficience when compared with the total export of korea. In this study, we used the gravity model to analyze the trade volume of the Daegu-Gyeongbuk region and Central Asian CIS countries. The result of analysis is that the globalization of Central Asian CIS countries appeared to be effective in increasing trade. In order to increase trade, Korea and CIS countries should strengthen their economic cooperation. Especially, these countries should try to implement FTAs for economic integration. The Central Asian CIS countries have an industrial structure that relies on resource exports. So, they have a blueprint for diversification of industries through national long-term plans. The Daegu-Gyeongbuk region's economy has been going through long-term stagnation. If the Daegu-Gyeongbuk companies can enter the Central Asian CIS countries, it can be a solution for the local economy.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.353-359
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• 2004

The extent of silica flocculation can be modified by varying the silica concentration, aqueous phase pH, salt and polvmer concentration. High volume fraction W/O emulsion stabilized by hydrophobic silica was established with various aqueous phase conditions for cosmetic application. By increasing the silica concentration up to $1.0\;wt\%,$ the size of droplet decreased. A high silica concentration increased the viscosity of continuous oil phase by network formation, which resulted in target size of droplet. The stability of W/O emulsion is improved as increasing the aqueous phase pH. At low and intermediate pH, the emulsions became more stable by adding salt $(0.083\;mol\;dm^{-3}\;MgSO_4).$ At high PH, the presence of salt caused significant destabilization. The gelation behavior of the emulsion indicates that the effect of salt on silica-stabilized emulsion is derived from an electrostatic attraction. The addition of xanthan gum in aqueous phase increased the mono-dispersity of the W/O emulsion by making water more hydrophobic and hindering the recombination of droplets. In conclusion, these results indicate that very stable emulsifier-free, finely dispersed W/O emulsion can be achieved for cosmetic application by changing the aqueous phase composition.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.5
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• pp.538-555
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• 2012

The purpose of this study was to understand $PM_{2.5}$ chemical characteristics on the Suwon/Yongin area and further to quantitatively estimate $PM_{2.5}$ source contributions. The $PM_{2.5}$ sampling was carried out by a high-volume air sampler at the Kyung Hee University-Global Campus from November, 2010 to October, 2011. The 40 chemical species were then analyzed by using ICP-AES(Ag, Ba, Cr, Cu, Fe, Mn, Ni, Pb, Si, Ti, V and Zn), IC ($Na^+$, $K^+$, $NH_4{^+}$, $Mg^{2+}$, $Ca^{2+}$, $NO_3{^-}$, ${SO_4}^{2-}$ and $Cl^-$), DRI/OGC (OC1, OC2, OC3, OC4, OP, EC1, EC2 and EC3) and GC-FID (acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[a] pyrene, indeno[1,2,3-cd] pyrene, benzo[g,h,i]perylene and dibenzo[a,h,]anthracene). When applying PMF model after performing proper data treatment, a total of 10 sources was identified and their contributions were quantitatively estimated. The average contribution to $PM_{2.5}$ emitted from each source was determined as follows; 26.3% from secondary aerosol source, 15.5% from soil and road dust emission, 15.3% from vehicle emission, 15.3% from illegal biomass burning, 12.2% from incineration, 7.2% from oil combustion source, 4.9% from industrial related source, and finally 3.2% from coal combustion source. In this study we used the ratios of PAHs concentration as markers to double check whether the sources were reasonably classified or not. Finally we provided basic information on the major $PM_{2.5}$ sources in order to improve the air quality in the study area.

• Journal of Distribution Science
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• v.11 no.8
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• pp.5-14
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• 2013

Purpose - We live in a world of constant change and competition. Many airports have specific competitiveness goals and strategies for achieving and maintaining them. The global economic recession, financial crises, and rising oil prices have resulted in an increasingly important role for facility investment and renewal and the implementation of appropriate policies in ensuring the competitive advantage for airports. It is thus important to analyze the factors that enhance efficiency and productivity for an airport. This study aims to determine the efficiency levels of 20 major airports in East Asia, Europe, and North America. Further, this study also suggests suitable policies and strategies for their development. Research design, data, and methodology - This paper employs the DEA-CCR, DEA-BCC, and DEA-Malmquist production index analysis models to determine airport efficiency. The study uses data on the efficiency and productivity of the world's leading airports between 2006 and 2010. The input variables include the airport size, the number of runways, the size of passenger terminals, and the size of cargo terminals. The output variables include the annual number of passengers and the annual cargo volume. The study uses basic data from the 2010 World Airport Traffic Report (ACI). The world's top 20 airports (as rated by the ACI report) are investigated. The study uses the expanded DEA Model and the Super Efficiency Model to identify the most effective airports among the top 20. The Malmquist productivity index analysis is used to measure airport effectiveness. Results - This study analyzes longitudinal and cross-sectional data on the world's top 20 airports covering 2006 to 2010. A CCR analysis shows that the most efficient airports in 2010 were Gatwick Airport (LGW), Zurich Airport (ZRH), Vienna Airport (VIE), Leonardo da Vinci Fiumicino Airport (FCO), Los Angeles International Airport (LAX), Seattle-Tacoma Airport (SEA), San Francisco Airport (SFO), HongKong Airport (HKG), Beijing Capital International Airport (PEK), and Shanghai Pudong Airport (PVG). We find that changes in airport productivity are affected more by technical factors than by airport efficiency. Conclusions - Based on the study results, we offer four airport development proposals. First, a benchmark airport needs to be identified. Second, inefficiency must be reduced and high-cost factors need to be managed. Third, airport operations should be enhanced through technical innovation. Finally, scientific demand forecasting and facility preparation must become the focus of attention. This paper has some limitations. Because the Malmquist productivity index is based on the hypothesis of the, the identified production change could be over- or under-estimated. Further, as DEA estimates the relative efficiency. It also cannot generalize to include all airport conditions because the variables are limited. To measure airport productivity more accurately, other input variables and environmental variables such as financial and policy factors should be included.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.704-708
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• 1994

This study was performed to compare quality of citron juice as affected by the extraction method. The yield of citron juice was 24.49% by method I (rotary-crushing and screening), 18.09% by method II (pressing) and 12.60% by method III (belt-pressing), respectively. Juices by methods I and II had more soluble solid contents and essential oil and pulp volume than that by method III. Method III was higher in titratable acidity than methods I and II. The contents of fructose, glucose and sucrose in method III were 0.54%, 0.37% and 1.11%, respectively, which were lower values than those in other methods. But there was no siginificant difference in the contents of total sugar by the extraction method. For fatty acids composition, the contents of oleic acid in method I, palmitic acid, linoleic acid and linolenic acid in method II, and stearic acid in method III, respectively, were highest when compared with other methods. The contents of free amino acids detected in method III were smaller than those in methods I and II. Threonin was detected only in method I, methionine and cystine were not detected in methods I. II and III. But the contents of the total amino acids in method III were $1.3{\sim}1.6$ times as large as those in methods I and II.

• Journal of Plant Biotechnology
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• v.42 no.2
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• pp.117-122
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• 2015

Canola is a crop globally used for production of oil and biofuel. Cultivation area and import volume of living modified (LM) canola have been increasing every year. As canola import dependence has reached 100% in Korea, efforts have been made for safety management of LM canola and ecological risk assessment. We developed a set of multiplex PCR method for simultaneous detection of 5 LM canola events (Topas 19/2, Rf3, Ms8, RT73 and T45) approved in Korea. The multiplex PCR assay developed allows amplification of estimated products of 5 LM canolas from event specific primer sets. Primer extension time was skipped for a time-consuming process and two annealing steps (20 cycles at $55^{\circ}C$ and 20 cycles at $60^{\circ}C$) were performed for yielding the best result which was sufficient to distinguish five LM canolas. Our results suggest that multiplex PCR method provides a cost and time-effective approach for LM canola detection.

• Journal of Korea Soil Environment Society
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• v.5 no.1
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• pp.13-23
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• 2000

The effects of operating condition of soil vapor extraction system and the characteristics of site on the remediation of oil contaminated soil were investigated. Thorough investigation showed that the site was contaminated with gasoline leaked from underground storage tank and the maximum concentration of BTEX and TPH were 1,081 ppm and 5,548 ppm respectively. The leaked gasoline were diffused to 6m deep and the area and volume of the polluted soil were assumed to 170$m^2$ and 1,000$\textrm{m}^3$respectively. The site were consisted of three different vertitical layers, the top reclaimed sandy soil between the earth surface and 3~4m deep, middle silty sand between 3~4m and 6m deep, and the bottom bedrock below the 6m deep. The air pemeability of soil was measured to 1.058-1.077$\times$10$^{-6}$ $\textrm{mm}^2$ by vacuum pump tests. The groundwater which level was 3~4m deep was observed in some areas of this site. The soil vapor extraction system which had 7.5 HP vacuum pump and 8 extraction wells was constructed in this site and operated at 8 hrs/day for 100 days. The BTEX was removed with above 90% efficiency where no groundwater and silty sand were observed. On the contrary, the efficiency of BTEX and TPH were dramatically decreased where groundwater and silty sand were observed. The flow rate of soil air induced by soil vapor extraction system was reduced in deeper soil.