• Journal of Climate Change Research
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• v.5 no.1
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• pp.83-94
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• 2014

Gangnam-gu, where the survey of residents' consciousness has been made in this study, is the district shows the highest rate of the energy consumption and greenhouse gas emission per unit area except some industrial districts such as Gwangyang, Ulsan, and Pohang. The greenhouse gas emission amount of Gangnam-gu is 4,863,765 $tCO_2$ which accounts for 10 % of the total discharging amount of Seoul, 50,330,356 $tCO_2$, which is ranked the top greenhouse gas emission rate in the commercial category and the 2nd place in the household category. The average recognition rate for the 5 subjects of the global warming phenomenons has indicated to be 83.58%. A survey questioning about the main agent to reduce the greenhouse gas, in all age groups except 20s have replied that it should be done by themselves, the residents of Gangnam-gu. For the question of the role of local government to respond to the climate change, the necessity of establishing infrastructure which is suitable for walking and biking. For the other question about the educational facilities to cope with the climate change, many answered the relevant education should be processed from the middle and high schools. For the practical activities in daily life to respond to the climate change, many replies have shown that the energy and resource conservation has been practiced pretty well broadly, but the ecomileage (former carbon mileage) has not been practiced well. Also, many replies have pointed that there were no benefits or rewards for the people who practiced the eco-mileage in their daily lives, which indicates that a kind of incentive is necessary for the efforts to respond to the climate change from the local government to execute the policy substantially and effectively. This study has the purpose to search the political countermeasures to improve the potentiality to reduce the green house gas emission rate through the residents conscious survey about climate change and the political solution by the local government to improve the certain items which showed the lower awareness rate.

• Korean Chemical Engineering Research
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• v.52 no.6
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• pp.720-726
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• 2014

PEM fuel cell vehicles have been getting much attraction due to a sort of highly clean and effective transportation. The onboard fuel processor, however, is inevitably required to supply the hydrogen by conversion from some fuels since there are not enough available hydrogen stations nearby. A lot of studies have been focused on analyses of ATR reactor under the assumption of thermo-neutral condition and those of the optimized process for the minimization of energy consumption using thermal efficiency as an objective function, which doesn't guarantee the maximum hydrogen production. In this study, the analysis of optimization for 100 kW PEMFC onboard fuel processor was conducted targeting various fuels such as gasoline, LPG, diesel using newly defined hydrogen efficiency and keeping simply synthesized heat exchanger network regardless of external utilities leading to compactness and integration. Optimal result of gasoline case shows 9.43% reduction compared to previous study, which shows the newly defined objective function leads to better performance than thermal efficiency in terms of hydrogen production. The sensitivity analysis was also done for hydrogen efficiency, heat recovery of each heat exchanger, and the cost of each fuel. Finally, LPG was estimated as the most economical fuel in Korean market.

• Journal of Environmental Policy
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• v.5 no.4
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• pp.1-18
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• 2006

Recently, the damage by fresh flood increases in Gangwon-do and Gyeongsangbuk-do of the north-eastern area of Korea. Even though the recent pattern of rain fall keeps changing, there is no strategy to mitigate damage by disaster. For the appropriate measure and policy for decreasing damage, an index for vulnerability is necessary to provide evidence of local climate change. The present work analyzes the flooding damage cost during the past 20 years. During 80's, the southern area of Korea was seriously damaged by over-floods on the agricultural ground. After that time, the loss and damage has decreased in the southern area but the middle part has shown slight but distinct increases of damage. The absolute coast of damage in the northern part has kept constant. However, the relative regional damage to the total country damage has kept increasing over 20 years in the same area. The surface area of floods is strongly correlated with the regional damage cost in the southern part but the north-eastern part has weak correlation between flooded area and cost. It implies that the recent damage in the north-eastern mountain area was not caused by flood itself but the other factors such as avalanches. The present work expects that the damage cost can be a good proxy value for index for climate change impact assessment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.577-586
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• 2018

In Korea, sustainability is mandatory in every field. University campuses are educational facilities that consume considerable amounts of energy. Therefore, many universities have tried to take advantage of the last opportunity to prepare students with sustainability and leadership. This study compared the green campus policy and evaluation criteria among Korea, US AASHE, UNEP, and ISCN-GULF to vitalize the green campus movement and suggest recent research data for the Korea green campus accreditation. The results are as follows: 1. new evaluation criteria need to be added to the certified green building total floor area ratio instead of adapting the G-SEED system in the Campus Resource & Environments category; 2. Korean Green Campus Evaluations need to be improved when expressing the campus individuality by choosing an increased number of credits and criteria; and 3. new evaluation criteria are required to secure the result, feedback, and products from curriculum updates in the Campus Education category.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.599-608
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• 2017

This paper proposed a methodology to analyze the economic and quantitative effects of lifting the import ban on Japanese pears by applying a price gap approach in the absence of any preference for either type of pear. Assuming that Korea will allow Japanese pear imports in 2018, the simulation results show that an annual average of 50,000 tons will flow into the domestic market from Japan. These imports will cause a decrease in the price and production of domestic pears, which would have a direct effect on the domestic pear industry, leading to an annual average reduction of 93 billion won. The cultivation area and production quantity are projected to be decreased by 0.7% and 1.4%, respectively, compared to the baseline. Also, the annual average reduction in the overall agriculture sector is predicted to be about 209 billion won, which is a 0.4% reduction compared to the baseline. This research is expected to improve the methodologies available for proactive analysis, with the existing analysis focused on customs tariffs when Korea considers joining mega-FTAs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.1
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• pp.257-263
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• 2010

We studied about the difference of division public announcements by corporation size and ownership structure from 1999 to 2005. The results is as follow : First, we found most positive numbers in division corporation's CAR. This supports the existing research that corporation division is evaluated positively in the market. We found CAR as largest shareholders' holding more than 40%, which is greater than 0-20% & 20-40%, that shows relatively more negative CAR. So, the exceeded largest shareholders' holding rate (i.e., over 40%) can be a factor for decreasing corporations' value. Also, most positive CAR shows relatively small variation regarding corporation size knowing that big sized corporations have relatively small variation than small sized corporations. Second, we studied about relationship between corporate ownership structure and division public effects and found relatively a little effect by large shareholders, foreign investors' holding variables on division public.

• Journal of Korea Port Economic Association
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• v.32 no.4
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• pp.127-147
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• 2016

This study proposes the improvement scheme of the current lease rate assessment system (2003~2014), as a major problem solving area, for the Terminal Operating Company (TOC)'s wharf since the introduction of the TOC system in 1997. The study considers the reform system using three criteria: standardization, simplification, and fairness. The final alternative presented by the study adopts the lease rate assessment system, which newly reflects changes of facilities' property values for aprons, combining it with the related fees of the Korean seaport dues for open storage yards, warehouses (shed), passages, buildings and lands within leased facilities. The proposal anticipates that the new system will not only minimize stakeholders' confusion, but also resolve the main problems within the current system. The study, further, introduces the adjustment ratio, which will make the new lease rate of the apron equal to the current lease rate of a berth, for the individual TOC's wharf, in order to prevent a sharp increment in the lease rate of the apron. This is because the government or port authorities as lessors, need to give priority to lightening the burden of TOC's costs under the deteriorating business environment such as the slowdown in port throughputs' growth. This study makes a contribution by suggesting a new lease rate assessment system for the TOC's wharf, reflecting the value of property as well as leading to its simplification and standardization. Additionally, it may lead to the improvement of fairness by applying the same rate to all leased wharfs for the lease rates of open storage yards, warehouses (shed) and passages. However, it has a limitation that hinders the fairness: the lease rate for the apron cannot be imposed in proportion to the leased area, by applying the individual adjustment ratios. In the future, those adjustment ratios should be, gradually, rationalized to be the same target ratio (0.5) for each wharf, following an improvement in the terminal operating business environment.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.158-158
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• 2016

최근 화석연료의 고갈과 환경 보전 및 에너지 절약에 대한 관심이 높아짐에 따라 화석연료의 소비를 최소화하고 실내조건을 쾌적하게 유지하려는 연구가 진행되고 있다. 국내의 경우 전체 에너지 소비의 30%이상을 차지하고 있는 건물부문에서의 에너지 소비를 줄이기 위한 활발한 연구가 진행되고 있으며 이에 따른 에너지절약 소재개발이 활발하게 진행되고 있다. 1975년 이후 여러 차례에 걸친 단열강화 조치를 통해 건물에서의 에너지 소모를 줄이고 있었으나 건물의 외벽에 대한 사항으로 한정되어있었고, 또한 건물의 창 면적이 증가함에 따라 창을 통한 열손실량과 열획득량이 더욱 증가하게 되었다. 이러한 문제를 해결하기 위해 열반사유리에 대한 많은 연구가 진행되고 있다. 열반사유리는 근적외선(열선)영역의 빛을 반사시켜 실내의 열손실량 및 외부에서의 열획득량을 감소시켜 에너지의 소비를 줄일 수 있는 유리을 말한다. 이러한 열반사유리은 fresnel 방정식을 통해 빛의 파장대에 따른 반사율 및 투과도를 예측할 수 있는데, 다층박막구조인 Oxide-Metal-Oxide(OMO)구조는 Oxide의 높은 굴절률과 Metal의 낮은 굴절률을 통해 가시광영역대의 높은 투과도와 근적외선 영역의 높은 반사율을 얻을 수 있다. 또한 Metal층을 삽입함으로서 flexible한 코팅이 가능하고, 높은 carrier density와 mobility로 표면 플라즈몬 공명을 통해 특정 파장대의 반사율을 높일 수 있으므로 많은 연구가 진행되고 있다. $TiO_2$는 고굴절률 및 낮은 광흡수성의 특성을 가지는 산화물반도체로 기존의 $In_2O_3$계 산화물에 비해 값이 싸고 높은 안정성과 광촉매특성을 보이므로 외부에 노출된 환경에 적합한 재료이다. Ag는 저굴절률과 낮은 광흡수성을 가지는 재료로 금속층에 적합하다. 본 연구에서는 fresnel 방정식을 통해 반사도 및 투과도를 예측하고 마그네트론 스퍼터링법으로 다층박막을 열선인 적외선 영역에서의 반사율 및 반사 효율을 평가하였다. Index-matching 시뮬레이션을 통해 $TiO_2/Ag/TiO_2$ 다층박막의 투과도와 반사도를 이론적으로 검토하였다. 시뮬레이션 프로그램은 Macleod프로그램을 이용하였고 재료 각각의 굴절률은 Ellipsometry를 이용하여 측정하였다. 두께 40 nm 와 8 ~ 16 nm를 가지는 $TiO_2$층과 Ag층을 각각 RF/DC 마그네트론 스퍼터링법을 이용하여 Glass기판 위에 증착하였다. 직경 3 in 의 $TiO_2$, Ag 소결체 타깃을 이용하였고 스퍼터링 파워는 각각 200 W, 50 W로 설정하였고, 스퍼터링 가스는 Ar가스의 유량을 20 sccm으로 설정하였다. 작업압력은 모두 1 Pa로 설정하였고 타깃 표면의 불순물 및 이물질 제거를 위해 Pre-sputtering을 10분 진행하였다. 박막의 두께는 reflectometer와 Alphastep을 이용하여 측정하였고 Hall effect measurement를 이용하여 비저항, carrier density, mobility등 전기적 특성을 측정하였다. 또한 UV-VIS spectrometer와 USPM-RU-W NIR Micro-Spectrophotometer를 통해 광학적 특성을 측정하였고 계산 값과 비교분석하였다. 또한 열반사 특성을 평가하기 위해 직접 set-up한 장비를 이용하였다. 단열 박스에 샘플을 장착해 적외선 램프를 조사하였을 때의 열 반사효율을 평가하였고, IR Camera를 이용하여 단열 박스 내부의 온도 변화를 관찰하였다.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.202-208
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• 2020

The objective of this study was to select the right species among Agastache in the family Lamiaceae as the result of growth analysis and functional substance analysis. Among 22 species of Agastache, five species (Agastache cana, Agastache foeniculum, Agastache rugosa 'Spike Blue', Agastache rugosa 'Spike Snow', Agastache rupestris) were selected by referring to United States Department of Agriculture (USDA)'s plant hardiness zone area and Korea's one based on USDAs. These plants were cultured at 24 ± 1℃ and 18 ± 1℃ (day and night temperatures, respectively) and 65 ~ 75% relative humidity in a hydroponic culture system for 4 weeks. In terms of growth analysis experiment, stem length, root length, leaf width, leaf area, leaf number, SPAD value, and fresh and dry weights of shoots and roots were measured. The results showed that A. rugosa SS and A. rugosa SB have a higher overall balance value than other species. When compared functional substance value (rosmarinic acid, tilianin, and acacetin) of five species, A. rugosa SS and A. rugosa SB are significantly higher than other species in Agastache. It seems to be directly proportional to the growth analysis results. When considering the growth and functional substance part comprehensively, A. rugosa SS and A. rugosa SB are the most optimal high-value species among Agastache.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.2
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• pp.269-288
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• 1999

현재 골 유착성 임플랜트는 안전하고 유용한 보철 수복 분야의 하나로 자리잡아 가고있다. 과거 완전 무치악 환자에게 있어서 저작 기능의 회복이란 면에 중점을 두었던 경향에서 현재 골유착 임플랜트의 높은 성공률에 의해 부문 무치악, 단일치 수복에 까지 다양하게 사용되고 있다. 특히 심미성과 인접치의 손상을 가하지 않는다는 면에서 단일치 수복에서 골유착 임플랜트 치료에 관심이 모아지고 있다. 단일치 수복에 있어서 심미성이 중요한 문제로 대두되면서 이런 수복에 사용될 수 있는 다양한 계통의 임플랜트들이 개발되어 사용되고 있다. 이중 가장 기본적인 Branemark 계통의 CeraOne 지대주, 최근에 개발된 전부도재 지대주인 CerAdapt 전부주조 지대주인 UCLA 계통등은 높은 성공률을 보이며 많이 사용되고 있다. 임상가들에 의해 나사유지형 보철물이 착탈성이란 관점에서 선호되고 있다. 시멘트유지형 보철물에서는 나사공이 없는 온전한 교합면을 유지한다는 면과 교합력을 받는 면적에 있어서 더 넓은 면을 가진다는 점등 더 많은 장점을 가진다고 주장하는 사람도 있다. 임상가들의 기호에 의해 선택되어지는 나사 유지형과 시멘트 유지형에 있어서 교합력이 야기하는 하중하에서 각각의 응력 분포를 분석할 필요성이 요구되었다. 이 연구는 단일치 수복에 사용되는 CeraOne, CerAdapt UCLA 계통에서 각각의 나사 유지형과 시멘트유지형에서의 응력분포를 삼차원 유한요소법으로 분석하고 상부 구조물에 가해지는 수직하중, 수평 하중, 경사 하중에 의해 야기되는 응력을 비교 분석한 것이다. 본 연구의 연구 결과는 다음과 같다. 1. CeraOne, CerAdapt, UCLA 지대주 모두 시멘트유지형보다 나사유지형에서 응력집중이 컸다. 2. CeraOne 시멘트유지형인 1번 모델에서 응력분산이 유리하였고, UCLA 나사 유지형인 6번 모델에서 가장 불리하였다. 3. 모든 모델에서 고정체 경부에서 가장 큰 응력 집중이 있었고 이것은 UCLA 지대주에서 가장 컸다. 4. 상부 구조물에서 주된 응력의 집중은 교합면에서 일어났다. 5. 골은 상부 피질골, 즉 고정체경부와 만나는 부위에서 가장 큰 응력의 집중이 일어났으며 수평, 경사 하중시 응력집중 양상은 힘을 가한 쪽의 반대쪽 고정체 경부에 응력이 집중되는 양상을 보였다. 6. 전체 모델과 골, 고정체 모두에서 수평 하중과 경사 하중시 보다는 수직 하중시 더 적은 응력값을 보였다.