• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.1-6
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• 1983

The results of COLE(Coefficient of Linear Extensibility) measurement on various paddy soils in Korea are summarized as follows; 1. The COLE values of paddy soil in Korea varied from 0.024 to 0.094 in the surface soil while in the sub-surface soils those were ranging from 0.022 to 0.115. The poorer the relative drainage and the finer the texture caused, the greater the COLE values. 2. The matured clayey soils on fluvio-marine plains and local alluvium derived from the Tertiary materials have COLE values more than 0.09 which is demonstrated that the necessity of COLE measurement throughout profiles so that could be considered the characteristic in the characteristic of those soils. 3. The clay content has the highest positive correlation (r=0.81~0.76) values. The content of organic matter, water content at 1/3 bar, Atterberg limits, water stable aggregate etc. also have significant positive correlation with COLE values while the context of sand and silt show negative correlation. 4. Although the COLE values measured on horizontal linear bases were slightly greater than those measured on volume bases practicability was for granted. For more accurate measurement of COLE, it is reasonable to have the average values of COLE calculated from the horizontal and vertical bases.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.2
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• pp.62-69
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• 2009

This study aimed to analyze citizen awareness of the transforming of a former military site in the city into use as an urban park, and to determine the direction of park creation in the context of urban regeneration. The study focused on the city of Uijungbu, so-called "representative military city" of Korea, which has over eight US military army corps in CBD and which islocated on the northside of Seoul. The questionnaire survey was carried out in the year of 2006, during two months from 1 June till 30 July. The research was carried out by book review as a theoretical base and a questionnaire survey to analyze citizen awareness. The conclusions of this study were as follows. 1. Areas that have been transformed from a former military site to large urban parks for the promotion of economic, social, environmental, and aesthetical value in the context of urban regeneration include Downsview Park(Toronto, Canada), and Great Park(Irvine, CA U.S.A). 2. The citizens of Euijungbu emphasized having casual rest and recreational functions in an urban park, but were also concerned with the promotion of cultural image, activation of the city's economy, etc. 3. The citizens preferred to use the former military site for a park instead of for residential and commercial purposes to introduce cultural facilities and encourage economic activation. 4. All results of this study proposed to use the former military site for encouraging and activating the urban economy, cultural promotion, social reconciliation and aesthetic value by the transforming the site into a large, multi-use park in the context of urban regeneration.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.202.1-202.1
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• 2015

탄소의 $sp^2$ 혼성으로 이루어진 2차원 단일시트(two-dimensional single sheet)인 그래핀은 기계적, 열역학적, 전기적 특성이 매우 우수하며 특히 고유연성과 투명성을 가진다는 장점 때문에 오랜 기간 주목 받으며 다양한 분야에서 연구되어 왔다. 이러한 그래핀을 만드는 방법에는 화학적 증기 증착법 및 흑연으로부터의 물리적, 화학적 박리 방법이 있다. 양질의 그래핀을 대면적에서 획득 할 수 있는 화학적 증기 증착법의 경우 높은 공정 비용과 함께 수반되어야 하는 전사과정의 어려움으로 인하여 실제 상용화에 어려움이 있다. 이러한 단점의 극복을 위해 대량의 그래핀을 저렴하게 확보 할 수 있는 화학적 박리 방법이 주목을 받고 있다. 화학적 박리 방법의 경우 박리 과정에서 수반되는 산화 그래핀의 환원과정이 필요하였으며, 이를 위해 강력한 환원제를 이용한 화학적 환원 방법, 고온에서의 열처리를 이용한 열역학적 환원 방법, 및 빛을 노광시켜 산화 그래핀을 환원시키는 광학적 방법이 시도되었다. 화학적 및 열역학적 환원방법의 경우 고품질의 환원된 산화 그래핀을 획득 할 수 있으나, 강한 환원제 및 높은 열처리 온도로 인하여 유연 기판의 사용이 제한되는 단점이 있다. 이러한 단점을 극복하기 위해 빛을 이용한 광학적 방법이 제시되었으나, 환원과정에 사용되는 단파장의 자외선 광원의 높은 가격으로 인하여 경제성의 확보가 제한된다. 본 논문에서는 우수한 광학적 특성을 보이는 란타넘족 이온을 사용하여 선택적 파장 대에서 높은 광흡수도를 가지는 산화 그래핀-란타넘 이온 혼합용액을 만들었으며, 가시광선대역의 파장을 가지는 레이저를 사용하여 우수한 품질을 가지는 환원된 산화 그래핀을 제작하였다. 구체적으로 산화 그래핀은 modified hummer's method를 이용하여 만들어졌으며, 자외선 대역을 흡수하는 $Gd_{3+}$, 녹색 레이저를 흡수하는 $Tb_{3+}$, 적색 레이저를 흡수하는 $Eu^{3+}$를 1 mM 섞어주었다. 그 후, 300~800 nm의 파장을 가지는 레이저를 $1mW/cm^2$를 노광시켜 산화 그래핀을 환원시켰다. 환원된 산화 그래핀의 특성은 FT-IR, UV-Vis, 저온 PL, SEM, XPS 및 전기측정을 이용해 측정하여 재현성 및 반복성을 확인하였다.

• Transactions of the KSME C: Technology and Education
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• v.1 no.1
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• pp.69-73
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• 2013

This study is about the secondary concentration technology using electrodialysis process for minimum discharge and maximize recovery ratio from seawater desalination by reverse osmosis process. The experimental method adopted the constant voltage driving method and, concentrated/desalination volume capacity ratio changes, voltage changes and electrolyte types. Multi-ion membrane is used, aiming to derive conditions to minimize the TDS concentration of desalination water, to minimize the volumes of secnodary concentraion water and minimizing the power efficiency. The results of this study are as follows. The optimal ratio of concentraion/desalination volume is 1:5, the final TDS concentration of desalinated water is 5.32g/l, the final secnodary concentrated water salinity is 17.07% and electric energy demands of desalinated water is $16.74kWh/m^3$.

• Polymer(Korea)
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• v.38 no.5
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• pp.573-579
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• 2014

The effect of synthesis conditions such as carbon nanotube (CNT), 2,2,2-trifluoroethylmethacrylate (3FMA), and composition of organic-inorganic material in ozone resistance and surface characteristics of ultraviolet cured organic-inorganic hybrid coating film has been investigated. Coating solution was prepared using tetraethoxysilane (TEOS), silane coupling agent methacryloyloxypropyltrimethoxysilane (MPTMS), 3FMA, various organic materials with acrylate group, and CNT, then bar-coated on substrates using applicator, and densified by UV-curing. It was found that ozone resistance and adhesion of the coating film were strongly dependent upon contents of TEOS, 3FMA, and CNT. Especially, ozone resistance, adhesion, and surface hardness of coating film with CNT were improved, relatively. Ozone resistance of coating film with a high TEOS content was increased, but adhesion was decreased. In addition, it was also found that ozone resistance of coating film was increased with contents of 3FMA. On the other hand, surface hardness was decreased with increase of 3FMA.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.421-426
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• 2012

The effect of synthesis conditions such as various organic material and composition of organic-inorganic material in ozone resistance and surface characteristic of ultraviolet cured organic-inorganic hybrid coating film has been investigated. Organic-inorganic hybrid coating solution was prepared using tetraethoxysilane (TEOS), silane coupling agent methacryloyloxypropyltrimethoxysilane (MPTMS), 2,2,2-trifluoroethylmethacrylate, and various organic materials with acrylate group, bar-coated on substrates using applicator and densified by UV-curing. It was found that ozone resistance and surface hardness of the coating film was increased with contents of TEOS. It was also found that ozone resistance of coating film was increased with contents of 2,2,2-trifluoroethylmethacrylate. On the other hand, surface hardness was decreased with increase of 2,2,2-trifluoroethylmethacrylate. In addition, Surface hardness of coating film was increased with the addition of aliphatic urethane acrylate. It was also found that the transmittance of coating films was not influenced by content of TEOS and 2,2,2-trifluoroethylmethacrylate. In addition, the coating film exhibited high transmittance of above 90%.

• Cross-Cultural Studies
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• v.40
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• pp.41-60
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• 2015

This article aims at exploring the convergence and sharing of cultural tastes among Northeast Asian countries by analyzing TV drama "Boys over flower", based on the original Japanese manga and produced in Korea, China, Japan and Taiwan in the $21^{st}$ century. It explores the expectation and desire of the mass who have taken pleasure in watching it in each country as well. This article argues that the sharing of the sensitivities and tastes of young women, the main consumer of the drama, by the mass of the four countries, are an important cultural phenomenon in that it reveals the emergence of "girl" as an active cultural consumer, who had been the object of a restraint and strict protection of the bourgeois family structure.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.102-102
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• 2021

광양만의 해수교환은 주로 여수해만을 통해 이루어지고, 만의 동측에는 노량수로를 통해 진주만으로의 해수교환이 일어나고 있으며, 만의 북측에는 섬진강을 끼고 있다. 광양항 건설 전 만내의 수심은 약 10 m 이내로 얕았으며, 만의 입구인 여수해만과 노량수로에서의 수심은 약 20 m 이상이었다. 광양만은 1982년 광양제철소의 건설을 시점으로 하여 광양항의 확장 개발, 폐기물처리장 건설 등으로 인한 매립이 진행되었다. 특히, 섬진강 하구는 광양만 개발 전에는 넓은 조간대 퇴적층의 발달로 다양한 생태계환경을 유지하고 있었으나, 광양항 건설 및 하구에서 모래 준설 등으로 인해 근래에 와서는 해수의 역류가 심각한 상태이다. 1982년 광양제철소 건설이후 계속적으로 광양만을 개발함으로써 해양환경에 큰 변화가 발생하였다. 따라서, 본 연구에서는 광양만 개발 전·후의 조석 및 해수유동의 변화특성을 해석하기 위해 조석 및 조류에 대한 현장관측과 3차원 해수유동 수치모형실험을 수행한 후 남해도를 둘러싸고 있는 광양만, 진주만 등의 조석 및 조류의 변동특성을 해석하였다. 광양만 개발 전·후의 해수유동의 변동특성을 해석하기 위해 김 등(1999)에 의해 개발된 3차원 layer·level 혼성 해수유동 모델을 광양만, 진주만을 포함하는 남해도 주변해역에 적용하여 30일간의 수치계산결과를 이용하여 해수유동의 변동특성을 해석하였다. 모델에서 격자간격은 동서-남북방향 동일하게 200 m, 시간간격은 20 sec, 계산영역은 동서방향으로 52 km, 남북방향으로 65 km인 260×325 격자체계로 구성 운영하였다. 외해 개방경계에서 조위는 수로국에서 관측한 조위와 본 연구에서 관측한 조위를 보간하여 사용하였다. 광양만 개발전·후의 조류의 변동특성을 수치해석한 결과 여수해만에서는 광만만 개발전이 개발 후보다 유속이 강하게 나타났으나, 노량수로에서는 개발 후가 개발전보다 유속이 훨씬 강하게 나타났다. 이와 같은 현상은 광양만 개발로 광양만으로 유입되는 조량이 감소함으로 인해 여수해만에서는 유속이 감소한 것으로 생각된다. 노량수로에서 개발 후가 개발전보다 유속이 증가한 것은 여수해만을 통해 유입한 해수가 개발 후에는 광양만의 해수면적 감소로 광양만의 서측으로 유입하는 조량이 감소한 반면에 광양만의 북측(섬진강 하구) 또는 동측(노량수로)으로 유입하는 조량이 많기 때문인 것으로 사료된다.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.3
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• pp.153-158
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• 1973

This report was presented to explain the relationships between various soil pH based on the present land use, nodes of depositions, and pH measurement methods ($H_2O$ and KCl extract). The samples were collected from 160 soil series in Korea. The results were summarized as follows. 1. The average pH ($H_2O$) of surface soil were $5.3{\pm}0.6$ for paddy soils, $5.5{\pm}0.9$ for upland, $5.4{\pm}0.5$ for forest soils, $5.3{\pm}0.6$ for grassland and $5.4{\pm}0.7$ for country average. 2. The average pH (KCl) of surface soil were $4.2{\pm}0.6$ for representative soils. Paddy soils had $4.2{\pm}0.6$; upland $4.2{\pm}0.8$; forest soils, $4.0{\pm}0.6$; and grassland, $4.3{\pm}0.6$. 3. The soil pH in B and C horizons were generally higher than that of A horizons. 4. The soil pH in field were correlated with lab. soil pH ($H_2O$) and pH (KCl). Field soil pH measured by pH kit could be highly accepted in accuracy compared with lab. pH of upland, grassland, forest and paddy soils. 5. Soil pH ($H_2O$) of surface based on mode of depositions was generally higher in residuum of mountainous and hilly land than those of Fluvio-marine deposits and old alluvium, however soil pH (KCl) was higher in fiuvio-marine deposits than those of mountainous and hilly land. It was shown that soil pH (KCl) was more reasonable than that of soil pH ($H_2O$) in practical use.

• Economic and Environmental Geology
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• v.49 no.4
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• pp.315-323
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• 2016

This study reports a gneiss dome in the Hongseong area, southwestern margin of the Gyeonggi massif. This gneiss dome, named here as 'Oseosan dome' because it is located around the Oseosan, the highest peak along the western coastal area, is composed mainly of the Neoproterozoic to Paleozoic ortho- and paragneiss, mafic metavolcanic rock, and metadolerite. Migmatization affected these rock units, in which leucocratic(granitic) materials derived from anatexis frequently occur as patch and vein parallel to or cutting through internal foliation. The Oseosan dome shows overall concentric geometry and outward-dipping internal foliation, but also partly complicatedly changeable or inward-dipping foliation. Taking available petrological and geochronological data into account, the Oseosan dome is interpreted to be exhumed quickly into the upper crustal level during the Late Triassic, accompanied in part with anatexis and granite intrusion. In addition, extensional shear zone intruded by the Late Triassic synkinematic granite and sedimentary basin have been reported around the Oseosan dome. These evidences possibly suggest that the Oseosan dome formed in closely associated with the Late Triassic extensional movement and diapiric flow. Alternatively, 1) thrust- or reverse fault-related doming or 2) interference between independent folds during structural inversion of the Late Traissic to Middle Jurassic sedimentary basin can be also considered as dome-forming process. However, considering the northern limb of the Oseosan dome, cutting by the Late Traissic granite, and the southern limb, cutting by contractional fault reactivated after the Middle Jurassic, it is likely that the domal structure formed during or prior to the Late Triassic.