• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.651-651
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• 2015

The Because reduction facilities of existing non-point pollution source weren't balanced with each element technologies, most of case were what damaged scene nature of river, neutralized pollution sources and reduction effect. Therefore it's necessary to find a solution by integrating the operation system. Based on the comparative analysis that we have ran, we examined the capacity at individual operation's water purification and linked the treatment to detention pond, wetland and revetment.

• Korea journal of population studies
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• v.35 no.2
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• pp.1-28
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• 2012

In this study, labor force projections are made in order to examine the process and magnitude of labor shortage caused by population ageing in Korea. Starting from theoretical review and analysis of population projection data, this study presents that serious transitions of labor market are expected to begin between 2020 and 2030. This study shows even in case of encouraging higher labor participation, labor shortage cannot be offset but only delay and alleviate effects of population ageing. Finally, this study points out some important implications of labor policy including sensitive social and political issues which should be considered.

• Journal of the Korean Chemical Society
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• v.37 no.5
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• pp.503-512
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• 1993

The purpose of this study was to investigate the retention behavior of phenols and to predict their retention in RPLC. The retention data of twenty-five phenols were measured on a $\mu-{Bondapak}\;C_{18}$ and a polymeric $C_{18}$ columns with methanol-water and acetonitrile-water as a mobile phase. From the observation of enthalpy-entropy compensation phenomenon, the following conclusions are drawn with regard to the retention mechanism: 1) the retention mechanism of nitrophenols in different from that of metheyl-and chlorophenols in both mobile phase; 2) in methanol-water mobile phase, the retention mechanism of methyl-and chlorophenols is consistent in the range of methanol-water composition; 3) on the other hand, in the case of acetonitrile-water mobile phase, the retention mechanism depends on the volume fraction of acetonitrile. It means that the retention mechanism can not be explained only by a simple interaction. Based on retention data as compared with two columns, it may be said that the hydrophobic interaction of phenols with polymeric $C_{18}$ column was greater than that with monomeric $C_{18}$ column. The equations for predicting the retention of phenols were derived by using hydrophobic substituent constant $(\pi)$ and the sum of Hammett's constant $(\sigma)$ and Taft's steric constant $(E_s)$.

• Journal of Life Science
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• v.22 no.1
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• pp.87-91
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• 2012

Phorbol 12-myristate 13-acetate (PMA), a known tumor-promoting phorbol ester, activates the signal transduction enzyme protein kinase C (PKC) in animal cells. We investigated the effect of PMA on the regulation of gravitropism via ethylene production in primary roots of maize. PMA stimulated root growth and the gravitropic response in a concentration-dependent manner at $10^{-6}$ M and $10^{-4}$ M over 8 hrs. These effects were prevented by treatment with staurosporine (STA), a potent inhibitor of PKC. These results support the possibility that the gravitropic response might be regulated through protein kinases that are involved in the signal transduction system. Ethylene is known to play a role in the regulation of root growth and gravitropism. Ethylene production was increased by about 26% and 37% of the control rate in response to $10^{-6}$ M and $10^{-4}$ M PMA, respectively. PMA also stimulated the activity of ACC synthase (ACS), which converts the S-adenosyl-L-methionine (AdoMet) to 1-aminocyclopropane-1-carboxylic acid (ACC) in the ethylene production pathway. These effects on ethylene production were also prevented by STA treatment. These results suggest that the root gravitropic response in maize is regulated through protein kinases via ethylene production.

• Environmental and Resource Economics Review
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• v.18 no.4
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• pp.557-586
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• 2009

Although energy demand management policy attracts attention internationally and domestically, the importance of local government in this policy is not so much as central government. But local government can do a role with regard to this policy because it is close to energy consumers not like central government. So local energy plan should be based on the understanding local energy consumption characteristics to activate local energy demand management policy. This paper tries to analyze energy characteristics of 16 local governments by decomposing energy consumption into population, production and intensity factors. The result of index decomposition analysis shows that energy intensity improvement has offset the increase of energy consumption caused by economic growth in the metropolitan cities, while it couldn't offset in the other provinces because of industrialization based on the manufacturing. In conclusion, this paper suggests that it will be necessary to switch to low energy society by carrying out concrete energy efficiency improvement projects in the metropolitan cities while it will be helpful to make a local development plan for low energy intensive industrialization in the other provinces.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.665-677
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• 2021

This study analyzed the optimization method of forest management to enhance economic and public functions, as well as the interrelationship among timber production, carbon storage, and water conservation functions in Mt.Gari leading forest management zone. For these purposes, a forest management planning model was developed using Multi-Objective Linear Programming. The model had an objective function to maximize the total NPV (Net Present Value) of weighted timber production, carbon storage, water conservation, and constraints to limit the rate of change in timber production, percentage of each age-class and tree species area, percentage of conifers and broad-leaved trees area in each management zone, minimum timber production and timber sales amount. Based on the description of forest inventory and the comprehensive plan of Mt.Gari, we analyzed stand information and management constraints of the study area. We compared management alternatives using different weights in the objective function. Therefore, the total NPV was maximized in the alternative considering the three functions in equal proportion, rather than the alternatives of maximizing only one function. When all three functions were considered simultaneously, timber production offset the carbon storage and water conservation, and carbon storage and water conservation interacted synergistically. However, when considering only two of the three functions, all combinations of functions demonstrated tradeoffs with one other. Therefore, we discovered that by considering all three functions equally, rather than only one or two functions, the economic and public values of the study area can be maximized.

• Korean System Dynamics Review
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• v.12 no.2
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• pp.127-151
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• 2011

The purpose of this study is to examine measures to improve government's supply oriented housing policy in population declining cities. For this purpose, system dynamics simulation method was used to build urban-housing model and different sets of housing policies were tested to see their impact on local housing problems. Simulation result shows that there is no best set of housing policies that can solve all housing problems in population declining cities. It also indicates that housing policy that solve one type of problems can worsen other type of problems. Housing policy that increases population size has negative effect of housing oversupply. It also increases proportion of old houses in population declining cities. However, housing policy that makes city younger with newer houses tends to increase housing shortage and housing price. So, policy choice needs to be made with clear understanding of trade off between different policies. The result also shows it is difficult to expect a full scale effect of housing policy on local housing problems unless it is executed with regional economic development policy because local housing problems are so closely related with local economic problem in population declining local cities.

• The Korean Journal of Financial Management
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• v.20 no.2
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• pp.263-291
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• 2003

The purpose of this paper is to analyse the change in the productivity of Korean life insurance industry by Generalized Malmquist productivity indices. Generalized Malmquist indices will be decomposed into three components such as pure efficiency change, scale efficiency change, and technical change. The principal findings indicate an overall increase in productivity driven more by technical progress than pure technical efficiency and scale efficiency.

• Journal of Labour Economics
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• v.31 no.2
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• pp.1-34
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• 2008

This study estimates what fraction of the rise in household income inequality in Korean between 1996 and 2000 is accounted for by the change in each of the household income components, such as wages, employment, hours of work of household heads and spouses, household structure, and other incomes. The increased disparities of household heads' wages and labor supply explain, respectively, 70% and 34% of the rise in the difference in incomes between the top 10% and bottom 10% households. Changing labor supply of spouses, in contrast, was a strong countervailing force that diminished the measure of household income inequality by 21%.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.691-691
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• 2013

최근 휴대용 전자기기의 전원으로서 가장 널리 사용되고 있는 리튬 이차 전지는 우수한 에너지 밀도, 낮은 자가방전 속도로 인한 비 메모리 효과, 높은 작동전압으로 다양한 전자기기뿐만 아니라 미래형 자동차산업 및 항공산업 분야에서도 점차 사용 빈도가 증가하고 있다. 현재 리튬 이차 전지의 음극물질로 널리 사용되고 있는 흑연의 경우 초기 용량 감소가 크고 이론적인 최대용량(372 mAhg-1, LiC6)이 낮다는 문제가 있어 다양한 대체물질의 연구가 진행되고 있다. 그 중에서도 Si는 Li과 반응하여 Li4.4Si합금을 형성하며 높은 이론용량을 갖고 상용화된 전지의 전압(~3.7 V)보다 0.3 V정도 밖에 낮지 않기때문에 재료의 개발과 함께 바로 사용화 할 수 있다는 장점이 있다. 그러나 Si의 경우 금속 자체로 사용되는 경우 Li 이온이 삽입되어 Li4.4Si형성 시에 310%의 부피 팽창을 일으키게 되어 분쇄반응(pulverization)을 일으키고 충 방전에 따라 급격한 용량 감소를 야기한다. 본 연구에서는 이러한 문제점을 해결하기 위하여 RF 마그네트론 스퍼터링을 이용하여 보다 간단한 방법으로 Si층 사이에 수 나노의 Al층을 삽입하여 Si 입자의 부피 팽창으로부터 오는 응력을 상쇄시켜 높은 방전 용량 특성과 우수한 수명 특성을 동시에 구현하였다.