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The Yellow Sea Ecoregion Conservation Project : the Present Situation and its Implications (황해생태지역 보전사업 추진현황 및 시사점)

  • Kim, Gwang Tae;Choi, Young Rae;Jang, Ji Young;Kim, Woong-Seo
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.4
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    • pp.337-348
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    • 2012
  • The Yellow Sea Ecoregion Conservation Project is a joint international project which is carried out under the purposes of conserving the habitats in the Yellow Sea Ecoregion and biodiversity from various threats that damage ecosystems, informing the importance and value of the Yellow Sea Ecoregion, and promoting the understanding and interests of Korea, China and Japan. Subsequent to the Yellow Sea Ecoregion Planning Programme which had been performed during the period from 2002 to 2006, the Yellow Sea Ecoregion Support Project has been performed over 7 years in total from 2007 to 2014. Panasonic is sponsoring the financing of the project, and the organizations in charge of the project by country are Korea Institute of Ocean Science & Technology for Korea and World Wide Fund for Nature branches for China and Japan. While the Yellow Sea Ecoregion Planning Programme was focused on the biological assessment and the selection of potential priority area by scientific review, the Yellow Sea Ecoregion Support Project is oriented toward practical activities targeting more diversified stakeholder. Especially, this project plans to support direct conservation activities in the region and participation and cooperation from local residents. The project plan is comprised of 3 phases. During the first period from 2008 to 2009, small grant projects were operated targeting 16 institutions of Korea and China, and for the second period from 2010 to 2012, one place each was selected as demonstration site for habitat conservation in Korea and China respectively and supported for three years to introduce the conservation method based on international standards such as the management of marine protected areas, ecosystem-based management and community-based management and simultaneously to develop habitat conservation activities suitable for national and regional characteristics. During the period from 2013 to 2014 which is the last phase, the project plans to distribute the performance of small grant projects and demonstration site activities through a series of forums among stakeholder. Through the activities described above, the recognition of general public on the conservation of the Yellow Sea Ecoregion was changed positively, and community-based management began to be reflected in the policies for the marine protected areas of central and local government.

A Study on Characteristics of Lincomycin Degradation by Optimized TiO2/HAP/Ge Composite using Mixture Analysis (혼합물분석을 통해 최적화된 TiO2/HAP/Ge 촉매를 이용한 Lincomycin 제거특성 연구)

  • Kim, Dongwoo;Chang, Soonwoong
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.1
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    • pp.63-68
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    • 2014
  • In this study, it was found that determined the photocatalytic degradation of antibiotics (lincomycin, LM) with various catalyst composite of titanium dioxide ($TiO_2$), hydroxyapatite (HAP) and germanium (Ge) under UV-A irradiation. At first, various type of complex catalysts were investigated to compare the enhanced photocatalytic potential. It was observed that in order to obtain the removal efficiencies were $TiO_2/HAP/Ge$ > $TiO_2/Ge$ > $TiO_2/HAP$. The composition of $TiO_2/HAP/Ge$ using a statistical approach based on mixture analysis design, one of response surface method was investigated. The independent variables of $TiO_2$ ($X_1$), HAP ($X_2$) and Ge ($X_3$) which consisted of 6 condition in each variables was set up to determine the effects on LM ($Y_1$) and TOC ($Y_2$) degradation. Regression analysis on analysis of variance (ANOVA) showed significant p-value (p < 0.05) and high coefficients for determination value ($R^2$ of $Y_1=99.28%$ and $R^2$ of $Y_2=98.91%$). Contour plot and response curve showed that the effects of $TiO_2/HAP/Ge$ composition for LM degradation under UV-A irradiation. And the estimated optimal composition for TOC removal ($Y_2$) were $X_1=0.6913$, $X_2=0.2313$ and $X_3=0.0756$ by coded value. By comparison with actual applications, the experimental results were found to be in good agreement with the model's predictions, with mean results for LM and TOC removal of 99.2% and 49.3%, respectively.

Efficient Red-Color Emission of InGaN/GaN Double Hetero-Structure Formed on Nano-Pyramid Structure

  • Go, Yeong-Ho;Kim, Je-Hyeong;Gong, Su-Hyeon;Kim, Ju-Seong;Kim, Taek;Jo, Yong-Hun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.174-175
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    • 2012
  • (In, Ga) N-based III-nitride semiconductor materials have been viewed as the most promising materials for the applications of blue and green light emitting devices such as light-emitting diodes (LEDs) and laser diodes. Although the InGaN alloy can have wide range of visible wavelength by changing the In composition, it is very hard to grow high quality epilayers of In-rich InGaN because of the thermal instability as well as the large lattice and thermal mismatches. In order to avoid phase separation of InGaN, various kinds of structures of InGaN have been studied. If high-quality In-rich InGaN/GaN multiple quantum well (MQW) structures are available, it is expected to achieve highly efficient phosphor-free white LEDs. In this study, we proposed a novel InGaN double hetero-structure grown on GaN nano-pyramids to generate broad-band red-color emission with high quantum efficiency. In this work, we systematically studied the optical properties of the InGaN pyramid structures. The nano-sized hexagonal pyramid structures were grown on the n-type GaN template by metalorganic chemical vapor deposition. SiNx mask was formed on the n-type GaN template with uniformly patterned circle pattern by laser holography. GaN pyramid structures were selectively grown on the opening area of mask by lateral over-growth followed by growth of InGaN/GaN double hetero-structure. The bird's eye-view scanning electron microscope (SEM) image shows that uniform hexagonal pyramid structures are well arranged. We showed that the pyramid structures have high crystal quality and the thickness of InGaN is varied along the height of pyramids via transmission electron microscope. Because the InGaN/GaN double hetero-structure was grown on the nano-pyramid GaN and on the planar GaN, simultaneously, we investigated the comparative study of the optical properties. Photoluminescence (PL) spectra of nano-pyramid sample and planar sample measured at 10 K. Although the growth condition were exactly the same for two samples, the nano-pyramid sample have much lower energy emission centered at 615 nm, compared to 438 nm for planar sample. Moreover, nano-pyramid sample shows broad-band spectrum, which is originate from structural properties of nano-pyramid structure. To study thermal activation energy and potential fluctuation, we measured PL with changing temperature from 10 K to 300 K. We also measured PL with changing the excitation power from 48 ${\mu}W$ to 48 mW. We can discriminate the origin of the broad-band spectra from the defect-related yellow luminescence of GaN by carrying out PL excitation experiments. The nano-pyramid structure provided highly efficient broad-band red-color emission for the future applications of phosphor-free white LEDs.

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Optical Absorption and Polarogram of Macrocyclic Nickel (II) Complexes in Polar Solvents (극성용매에서 거대고리 Ni (II) 착물의 광흡수와 폴라로그램)

  • Park Yuj-Chul;Jong-Chul Byun
    • Journal of the Korean Chemical Society
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    • v.31 no.2
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    • pp.168-177
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    • 1987
  • The equilibria of chemical reaction between $\alpha$-Ni(rac-[14]-decane)$^{2+}$ and polar solvents(L; ANT, MFA, DMSO, DMF, and DMA) have been investigated by the spectrophotometric method at $25^{\circ}C$. (The equilibrium constants($K_1$) of) the first step in ANT, MFA, DMSO, DMF, and DMA were 31.0, 27.5, 21.3 15.9, and 6.4, respectively. The smallness of equilibrium constants ($K_2$) of the second step compared with $K_1$, was observed. $\alpha$-Ni(rac-[14]-dacane)$^{2+}$ + L $\leftrightharpoons$ [$\alpha$-Ni(rac-[14]-decane){\cdot}L]$^{2+}$ : $K_1$.[$\alpha$-Ni(rac-[14]-decane){\cdot}L)$^{2+}$+ L $\leftrightharpoons$ [$\alpha$-Ni(rac-[14]-decane){\cdot}$L_2$)$^{2+}$ :$K_2$. The relationship between d-d absorption energy and half-wave potential of complex ions at ACT was considered. Macrocyclic ligands increasing d-d transition energy caused half-wave potentials of Ni(II)-macrocycle to be shifted more positively. The half-wave potentials for Ni(rac-1[14]7-diene)$^{2+}$, Ni(meso-1[14]7-diene)$^{2+}$, Ni(1[14]4-diene)$^{2+}$, $\alpha$-Ni(rac-[14]-decane)$^{2+}$, ${\beta}-Ni(rac-[14]-decane)$^{2+}$, and Ni(meso-[14]-decane)$^{2+}$ reductions were -1.419, -1.431, -1.450, -1.473, and -1.480 (V vs. SCE), respectively. The d-d transition energies ($\nu_{max},\;cm^{-1}$) of the Ni(meso-[14]-decane)$^{2+}$ isomer were discussed with the dielectric constant (${\varepsilon}/{\varepsilon}_0$) of the various solvents, $\nu_{max}(cm^{-1})$ increased with increasing ${\varepsilon}/{\varepsilon}_0$.

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Strategy for Development of HSE Management Framework for Offshore CCS Project in Korea (국내 해양 CCS 사업의 HSE 관리 프레임워크 구축 전략)

  • Noh, Hyonjeong;Kang, Kwangu;Kang, Seong-Gil;Lee, Jong-Gap
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.20 no.1
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    • pp.26-36
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    • 2017
  • Korea is preparing an offshore carbon capture, transport and storage (CCS) demonstration project which is recognized as one of important $CO_2$ reduction technologies to mitigate climate change. The offshore CCS project aims to transport, inject and store large amount of $CO_2$ into offshore geologic formation, and has a potential risk of leakage which might cause disastrous damage to human health, environment and property. Therefore, in order to ensure the safety of the offshore CCS project, a strict HSE (health, safety and environment) management plan and its implementation are required throughout the project life cycle. However, there are no HSE domestic laws or regulations applicable to CCS projects, and the related research is insufficient in Korea. For the derivation of the essential and urgent requirement in HSE management framework applicable to the offshore CCS project in Korea, we analysed the HSE management methodologies and foreign CCS HSE management guidelines and cases. First, this paper has analyzed ISO 31000, a generalized risk management principles. Second, we have investigated the HSE management practices of CCS projects in Norway and UK. Based on the analyses, we suggested the necessity of developing the HSE Philosophy and the HSE management process through the whole life cycle. Application of HSE management in early phase of an offshore CCS project will promote systematic and successful project implementation in a cost-effective and safe way.

Manganese and Iron Interaction: a Mechanism of Manganese-Induced Parkinsonism

  • Zheng, Wei
    • Proceedings of the Korea Environmental Mutagen Society Conference
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    • 2003.10a
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    • pp.34-63
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    • 2003
  • Occupational and environmental exposure to manganese continue to represent a realistic public health problem in both developed and developing countries. Increased utility of MMT as a replacement for lead in gasoline creates a new source of environmental exposure to manganese. It is, therefore, imperative that further attention be directed at molecular neurotoxicology of manganese. A Need for a more complete understanding of manganese functions both in health and disease, and for a better defined role of manganese in iron metabolism is well substantiated. The in-depth studies in this area should provide novel information on the potential public health risk associated with manganese exposure. It will also explore novel mechanism(s) of manganese-induced neurotoxicity from the angle of Mn-Fe interaction at both systemic and cellular levels. More importantly, the result of these studies will offer clues to the etiology of IPD and its associated abnormal iron and energy metabolism. To achieve these goals, however, a number of outstanding questions remain to be resolved. First, one must understand what species of manganese in the biological matrices plays critical role in the induction of neurotoxicity, Mn(II) or Mn(III)? In our own studies with aconitase, Cpx-I, and Cpx-II, manganese was added to the buffers as the divalent salt, i.e., $MnCl_2$. While it is quite reasonable to suggest that the effect on aconitase and/or Cpx-I activites was associated with the divalent species of manganese, the experimental design does not preclude the possibility that a manganese species of higher oxidation state, such as Mn(III), is required for the induction of these effects. The ionic radius of Mn(III) is 65 ppm, which is similar to the ionic size to Fe(III) (65 ppm at the high spin state) in aconitase (Nieboer and Fletcher, 1996; Sneed et al., 1953). Thus it is plausible that the higher oxidation state of manganese optimally fits into the geometric space of aconitase, serving as the active species in this enzymatic reaction. In the current literature, most of the studies on manganese toxicity have used Mn(II) as $MnCl_2$ rather than Mn(III). The obvious advantage of Mn(II) is its good water solubility, which allows effortless preparation in either in vivo or in vitro investigation, whereas almost all of the Mn(III) salt products on the comparison between two valent manganese species nearly infeasible. Thus a more intimate collaboration with physiochemists to develop a better way to study Mn(III) species in biological matrices is pressingly needed. Second, In spite of the special affinity of manganese for mitochondria and its similar chemical properties to iron, there is a sound reason to postulate that manganese may act as an iron surrogate in certain iron-requiring enzymes. It is, therefore, imperative to design the physiochemical studies to determine whether manganese can indeed exchange with iron in proteins, and to understand how manganese interacts with tertiary structure of proteins. The studies on binding properties (such as affinity constant, dissociation parameter, etc.) of manganese and iron to key enzymes associated with iron and energy regulation would add additional information to our knowledge of Mn-Fe neurotoxicity. Third, manganese exposure, either in vivo or in vitro, promotes cellular overload of iron. It is still unclear, however, how exactly manganese interacts with cellular iron regulatory processes and what is the mechanism underlying this cellular iron overload. As discussed above, the binding of IRP-I to TfR mRNA leads to the expression of TfR, thereby increasing cellular iron uptake. The sequence encoding TfR mRNA, in particular IRE fragments, has been well-documented in literature. It is therefore possible to use molecular technique to elaborate whether manganese cytotoxicity influences the mRNA expression of iron regulatory proteins and how manganese exposure alters the binding activity of IPRs to TfR mRNA. Finally, the current manganese investigation has largely focused on the issues ranging from disposition/toxicity study to the characterization of clinical symptoms. Much less has been done regarding the risk assessment of environmenta/occupational exposure. One of the unsolved, pressing puzzles is the lack of reliable biomarker(s) for manganese-induced neurologic lesions in long-term, low-level exposure situation. Lack of such a diagnostic means renders it impossible to assess the human health risk and long-term social impact associated with potentially elevated manganese in environment. The biochemical interaction between manganese and iron, particularly the ensuing subtle changes of certain relevant proteins, provides the opportunity to identify and develop such a specific biomarker for manganese-induced neuronal damage. By learning the molecular mechanism of cytotoxicity, one will be able to find a better way for prediction and treatment of manganese-initiated neurodegenerative diseases.

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A Study on the Effect of the Urban Regeneration Project on the Reduction of Carbon Emission - A Case Study of Jeonju Test-Bed - (도시재생사업 적용에 따른 탄소저감 효과 - 전주TB지역을 대상으로 -)

  • Park, Kiyong;Lee, Sangeun;Park, Heekyung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.1
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    • pp.65-74
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    • 2016
  • This study mainly focuses on urban regeneration project as a countermeasure to resolve climate change issues by analyzing the carbon-reduction effect of Jeonju test-bed cases. First, an urban regeneration project is designed for city, Jeonju by analyzing its environmental problems and potential improvement. Then, carbon emission and reduction amounts are evaluated for different businesses and scenarios. Carbon emission sources are classified according to a standard suggested by IPCC, and the emissions are calculated by various standard methods. The result shows that carbon emission amount in Jeonju test-bed is 102,149 tCO2eq. The fact that 70% of the emission from energy sector originates from buildings implies that urban regeneration projects can concentrate on building portions to effectively reduce carbon emission. It is also projected carbon emission will decrease by 3,826tCo2eq in 2020 compared to 2011, reduction mainly based on overall population and industry shrinkage. When urban regeneration projects are applied to 5 urban sectors (urban environment, land use, green transportation, low carbon energy, and green buildings) total of 10,628tCO2eq is reduced and 4,857tCO2 (=15.47%) when only applied to the green building sector. Moreover, different carbon reduction scenarios are set up to meet each goal of different sectors. The result shows that scenario A, B, and C each has 5%, 11%, and 15% of carbon reduction, respectively. It is recommended to apply scenario B to achieve 11% reduction goal in a long term. Therefore, this research can be a valuable guideline for planning future urban regeneration projects and relative policies by analyzing the present urban issues and suggesting improvement directions.

Current Status and Prospects of Community Nutrition in Korea (한국 지역사회영양의 현황과 전망)

  • 채범석;한정호
    • Korean Journal of Community Nutrition
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    • v.1 no.1
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    • pp.9-27
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    • 1996
  • The nutritional status is strictly related with flood production, flood processing, and distribution along with habits, education and technological achievement, adapted and adjusted to socio-economic conditions. All these factors are independently affecting the nutritional status of populations. In addition to the above mentioned factors launch of it is useful to consider two points ; unification of the South and the North Korea and WTO. The present study gives and overview of basic knowledge about nutritional status of Korean by using availab1e data in relation to nutrition. The basic characteristics of Korean diet with proportions high in carbohydrate and low in fat, have been relatively constant for the past two decades. The average daily flood intake in terms of weight of flood per person is relatively constant throughout the years. Although the proportion of animal food intake tends to increase recently, the Korean diet is still insufficient in meat, eggs, milk, and fish. Moreover because milk has not been accustomed flood with the general population and not much used in traditional flood preparation in Korea, milk consumption was especially low in comparison with western countries. The total energy intake was relatively constant throughout the years from 1969 to 1993. However, changes in the composition have occurred in the past two decades. The amount and proportions of fat have been s1ightly increasing while the total amount of carbohydrate has been decreasing. The nutrition preblems of Korea have changed over the past severa1 decades. The general adequacy of protein and energy existing after Korean War(1950) was resolved now. Since then the average diet appears to be nearly desirable in terms of rapid rates of growth during childhood and attainment of progressively stature and body weight at maturity. The dietary habits of some young people in these days seem to be taking a more western style diets. This trends if established by habit may lead to a marked change in the traditional diet and health. I think Korean nutritional experiences have potential values for tole other countries in Asia and in western countries. Korean diet illustrates a high level of nutritional status and health attainable will a largely vegetable diet : high in complex carbohydrates, and dietary fibre, and low in tat, and reasonable amount of total protein. This is significant for developing and developed countries that must select specific goals fir adequate nutrition for the people. Compared to the western countries, Koreas different incidence of coronary heart disease and malignancy demonstrates the significance of environment and probably the prominent role of diet in the development of these diseases. The changes occurring in the Korean diet of fir the unusual opportunity to assess the effect of diet upon chronic degenerative disease. In the future, the Korean diet might be continue to change significantly These changes are being influenced by socioeconomic factors that have been emerging and growing stronger since mid-l980 and that probably continue to be potent. The expanded purchasing power of the consumer results in increased discretionary purchases. In the case of foodstuffs, the consumer demands appear to be directed toward items of higher protein content, which, being primarily animal products, are inevitably accompanied by an increased consumption of fat. The continued availability of these more expensive flood items depends upon the balance of foreign trade favouring their importation and domestic production. A regression of foreign trade could result in a decreased supply for the consumer, whereas continued growth of trade iou]d provide freedom for increasing availability to the consumer. In this latter situation the exact choice of foodstuffs is depending upon comsumer tastes and the pressures that may influence it.

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Reduction of Carbon-Dioxide Emission Applying Carbon Capture and Storage(CCS) Technology to Power Generation and Industry Sectors in Korea (국내 전력 발전 및 산업 부문에서 탄소 포집 및 저장(CCS) 기술을 이용한 이산화탄소 배출 저감)

  • Wee, Jung-Ho;Kim, Jeong-In;Song, In-Sung;Song, Bo-Yun;Choi, Kyoung-Sik
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.9
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    • pp.961-972
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    • 2008
  • In 2004, total emissions of Greenhouse Gases(GHGs) in Korea was estimated to be about 590 million metric tons, which is the world's 10th largest emissions. Considering the much amount of nation's GHG emissions and growing nation's position in the world, GHG emissions in Korea should be reduced in near future. The CO$_2$ emissions from two sub-sections of energy sector in Korea, such as thermal power plant and industry section(including manufacturing and construction industries), was about 300 million metric tons in 2004 and this is 53.3% of total GHG emissions in Korea. So, the mitigation of CO$_2$ emissions in these two section is more important and more effective to reduce the nation's total GHGs than any other fields. In addition, these two section have high potential to qualitatively and effectively apply the CCS(Carbon Capture and Storage) technologies due to the nature of their process. There are several CCS technologies applied to these two section. In short term, the chemical absorption technology using amine as a absorbent could be the most effectively used. In middle or long term, pre-combustion technology equipped with ATR(Autothermal reforming), or MSR-$H_2$(Methane steam reformer with hydrogen separation membrane reactor) unit and oxyfuel combustion such as SOFC+GT(Solid oxide fuel cell-Gas turbine) process would be the promising technologies to reduce the CO$_2$ emissions in two areas. It is expected that these advanced CCS technologies can reduce the CO$_2$ avoidance cost to $US 8.5-43.5/tCO$_2$. Using the CCS technologies, if the CO$_2$ emissions from two sub-sections of energy sector could be reduced to even 10% of total emissions, the amount of 30 million metric tons of CO$_2$ could be mitigated.

The Latest Progress on the Development of Technologies for $CO_2$ Storage in Marine Geological Structure and its Application in Republic of Korea (해저 지질구조내 $CO_2$ 저장기술의 연구개발 동향 및 향후 국내 실용화 방안)

  • Kang, Seong-Gil;Huh, Cheol
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.11 no.1
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    • pp.24-34
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    • 2008
  • To mitigate the climate change and global warming, various technologies have been internationally proposed for reducing greenhouse gas emissions. Especially, in recent, carbon dioxide capture and storage (CCS) technology is regarded as one of the most promising emission reduction options that $CO_2$ be captured from major point sources (eg., power plant) and transported for storage into the marine geological structure such as deep sea saline aquifer. The purpose of this paper is to review the latest progress on the development of technologies for $CO_2$ storage in marine geological structure and its perspective in republic of Korea. To develop the technologies for $CO_2$ storage in marine geological structure, we carried out relevant R&D project, which cover the initial survey of potentially suitable marine geological structure fur $CO_2$ storage site and monitoring of the stored $CO_2$ behavior, basic design for $CO_2$ transport and storage process including onshore/offshore plant and assessment of potential environmental risk related to $CO_2$ storage in geological structure in republic of Korea. By using the results of the present researches, we can contribute to understanding not only how commercial scale (about 1 $MtCO_2$) deployment of $CO_2$ storage in the marine geological structure of East Sea, Korea, is realized but also how more reliable and safe CCS is achieved. The present study also suggests that it is possible to reduce environmental cost (about 2 trillion Won per year) with developed technology for $CO_2$ storage in marine geological structure until 2050.

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