• Title/Summary/Keyword: Environmental issue

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Designation of fuel oil scrubber nozzle positioning using CFD analysis and PIV methods (CFD 해석 및 PIV 실험을 통한 연료유 스크러버의 노즐 위치선정)

  • Kim, In-Cheol;Kim, Chang-Goo;Park, Sung-Jin;Cho, Dong-Yeon;Lee, Young-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.7
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    • pp.773-778
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    • 2015
  • Global warming has recently become an issue that has resulted in a growing trend to minimize environmental pollution. The International Maritime Organization (IMO) has shown that the majority of marine atmospheric pollution occurs as a result of emissions from marine vessels. Therefore, the environmental regulations and emission standards regarding marine vessels have gradually become stricter, and the research and development in this area is experiencing significant progress. In this study, a nozzle for a fuel oil scrubber was investigated using computational fluid dynamics (CFD) and particle imaging velocimetry (PIV). Experiments were conducted on scaled-down model of the scrubber to determine its performance, which was then compared with CFD results. Based on the experimental results, it was found that at a spray angle of $66^{\circ}$, the spray velocity at the nozzle was 20.1 m/s. From this comparison, a full-scale scrubber model was analyzed using CFD, and the effect of the positioning of the nozzle was studied.

An Empirical Test for CVM Calibration Factor through Combining Revealed and Stated Preferences Data (현시선호와 진술선호 자료의 결합을 통한 조건부 가치측정법 소득조정계수의 추정)

  • Eom, Young Sook;Larson, Douglas M.
    • Environmental and Resource Economics Review
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    • v.13 no.3
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    • pp.337-366
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    • 2004
  • Contingent Valuation Method (CVM), as non-market valuation approach, has been criticized on that respondents may not realistically reflect their budget constraints in answering willingness to pay (WTP) for hypothetical CV questions. This paper empirically estimates the income calibration factor associated with CV responses through combining travel cost method and contingent valuation method in a utility-theoretic framework. The joint model of recreation demand function and contingent WTP function was applied to an important case study on the Man Kyoung River system, whose water quality is at issue because of the Sae Alan Kum reclamation project. Relevant economic variables such as price, income and water quality had significant influence as anticipated by the economic theory. Equally important, the income calibration factor was not significantly different from one, suggesting that the systematic discrepancies of CV responses relative to the actual behavior was not detected at least in terms of budget exaggeration. Overall, this study supports the notion that carefully designed CVM studies can provide informative data on individuals' willingness to pay for environmental quality changes.

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A Valuation for Gas Hydrate R&D Project Using Fuzzy Real Options Model (퍼지실물옵션모형을 이용한 가스하이드레이트 R&D 사업의 가치평가)

  • Yun, Ga-Hye;Heo, Eunnyeong
    • Environmental and Resource Economics Review
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    • v.18 no.2
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    • pp.217-239
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    • 2009
  • As gas hydrate is recently emerging as a new energy source to solve environmental and exhaustion problems caused by fossil energy, Korea is working on a gas hydrate development project under a 10-year plan from 2005 to 2014. Gas hydrate is expected to have a big effect on the economy and society of Korea, which is largely depending on energy imports besides water energy and atomic energy. However, it is uncertain whether the project will produce successful results. Thus, it is very important to improve its validity and to propose effective execution strategies by evaluating the value of the project in advance. Thus, this study intended to include new information, which had not been evaluated in existing methods, and to reduce biases or errors in value evaluation results by applying a fuzzy risk analysis to the real option model in order to evaluate the value of a gas hydrate development project. It is advantageous that the real option model based on the fuzzy risk analysis modelizes the vagueness and inexactness of intangible element judgment into an appropriate language scale so as to evaluate these elements clearly and integrate them with estimated financial performance results. The application of the fuzzy risk analysis makes it possible to conduct an analysis by dissolving a decision-making issue with complicated and various attributes into several simplified problems. With the continuing high oil prices and today's demand of clean energy, the necessity of energy resources and technology development projects keeps growing. Amid this situation, it is expected that these study results will contribute to proposing a guideline not only for gas hydrate projects but also for policy decision-making related to future energy industries.

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Feasibility Study for Tidal Power Plant Site in Garolim Bay Using EFDC Model (EFDC모형을 이용한 가로림만의 조력발전 위치 타당성 검토)

  • Shin, Bum-Shick;Kim, Kyu-Han;Kim, Jong-Hyun;Baek, Seung-Hwa
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.23 no.6
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    • pp.489-495
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    • 2011
  • Fossil fuel energy has become a worldwide environmental issue due to its effect on global warming and depletion in its supply. Therefore, the interest in developing alternative energy source has been rising. Ocean energy, especially, has gained strength as an alternative energy source for its unlimited supply with low secondary risks. Among all the ocean energy, the west coast of Korea holds the field of large-scale energy development because of its distinctive tidal range. Tidal power plant construction at the sea may expedite multi development effects such as bridge roles, tourism resource effects and adjustability of flood inundation at the inner bay. This study introduces the validity of tidal power plant construction at Garilim Bay in west coast of Korea by examining anticipated hydraulic characteristics using EFDC model. Through EFDC numerical simulations, the feasibility of Garolim Bay as a tidal power plant field has been proved. And the most effective tidal power plant construction would be to install hydraulic turbine in the west side of bay entrance where ebb current is stronger, and install water gate in the east side of bay entrance where the flood current is superior.

A Basic Study on the features of LID-related Ordinance Enactment conducted by Local Government - mainly on Seoul City, Suwon City and Namangju City - (LID관련 지방정부 조례제정 특성 기초연구 - 서울시, 수원시, 남양주시를 중심으로 -)

  • Lee, Mihong;Han, Yanghui;Hyun, Kyounghak;Lim, Seokhwa
    • Journal of Environmental Impact Assessment
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    • v.25 no.1
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    • pp.25-40
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    • 2016
  • This study suggests direction of new ordinance establishment for the future national application of Low Impact Development(LID) by analyzing current LID-related regulations of local governments, substantial agents to install and maintain a facility, through qualitative and quantitative methodologies. Four key words related to LID were derived from advisory conference and then ninety nine ordinances as the LID-related regulations were extracted to analyze. The study shows that rainwater-related ordinance passed in the middle of 2000s are being merely converted to the law on the promotion and support of water reuse. Regulations on water cycle and LID exist only in three cities nationwide(Seoul City, Suwon City and Namangju City). Interview with administrators of three cities to have LID-related regulations revealed following results. First, both rainwater and water reuse related regulations have not considered regional characteristics such as rainfall intensity, effects of impervious and merely followed guidelines by Ministry of Government Administration and Home Affairs. Second, existing ordinance is confined to specific facilities and thus cannot include the concept of LID which covers land and space utilization. Therefore, for proper application of LID, this study proposes issue of ordinance that resembles Seoul City ordinance and a new guideline that can reflect regional characteristics such as rainfall and location.

Analysis of Domestic and Foreign Local Biodiversity Strategies and Action Plan (LBSAP) using Semantic Network Analysis (언어네트워크 분석을 이용한 국내·외 지역생물다양성 전략 분석)

  • Lee, Hyeon-jae;Sung, Kijune
    • Journal of Environmental Impact Assessment
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    • v.27 no.1
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    • pp.92-104
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    • 2018
  • The loss of biodiversity has become a global issue. In order to cope with this problem, national biodiversity strategies and action plan (NBSAP) at national level as well as local biodiversity strategies and action plan (LBSAP) at local level have been established in many countries. In this study, we analyzed 8 domestic LBSAPs and 41 foreign LBSAPs through semantic network analysis to investigate the characteristics of domestic and foreign LBSAPs. The results showed that conservation and management were the most used keywords in both domestic and foreign LBSAPs but the ranking of other keywords used in vision, goal, strategy, and action plan sector was different. Thus, it has been found that there is a difference between domestic and foreign practical approaches to conservation and management of biodiversity. Results of the network analysis showed that the domestic network has a more detailed distributed network, while the foreign network has a more comprehensive and integrally configured dense network. These differences may be due to differences of threats to biodiversity, problem recognition, or differences in local circumstances. These results are expected to help establish LBSAP in other region or to assess the local roles to achieve the strategic goals of the Convention on Biological Diversity.

Micro-Geopolitics against the U.S. Forces in S. Korea: Local Problems Caused by the U.S. Military Bases and Strategies for their Resolution (주한미군의 미시적 지정학 - 미군기지로 인한 지역사회의 범죄 및 환경 문제의 발생과 해결방안 -)

  • Choi, Byung-Doo
    • Journal of the Korean association of regional geographers
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    • v.9 no.3
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    • pp.297-313
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    • 2003
  • Problems caused by the U.S. military bases have attracted little attention until recently due to the national security of S.Korea and the peace of North-Eastern Asia, emphasized from the perspective of macro-geopolitics. However, since the political regime has been democratized and political discourses have been liberalized from the 1990s, those problems become a nation-widely serious social issue, though they have been brought about on the local areas. Thus, it can be suggested that micro-geopolitics is highly relevant and significant in approaching the local problems caused by the U.S. military bases, and ultimately resolving the macro-geopolitical problem of longstanding unfair relations in the SOFA and the withdrawal of U.S. troops. This paper aims to consider local problems caused by the U.S. military bases and resolving strategies from the perspective of micro-geopolitics. First of all, it discusses some significance of the micro-geopolitical perspective, as it has been recently emphasized in political geography in considering local problems and politics of life on the basis of place, then looks on empirically criminal and environmental problems caused by the U.S. military bases, analyses the questionnaire date on the perception of local dwellers around the military camps in Nam-gu Daegu, and finally suggests strategies to resolve those problems, which level up from the micro to the macro-scale of geopolitics.

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Community Structure and Understory Vegetation Distribution Pattern of Fagus engleriana Stand in Is. Ulleung (울릉도 너도밤나무림의 군집구조와 하층식생의 분포특성)

  • Cheon, Kwang-Il;Jung, Sung-Cheol;Lee, Chang-Woo;Byeon, Jun-Gi;Joo, Sung-Hyun;You, Ju-Han;Lee, Seul-Gi;Choi, Cheol-Hyun;Park, In-Hwan
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.4
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    • pp.81-95
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    • 2012
  • This study was intended for Fagus engleriana stand in Is. Ulleung where the disturbance of vegetation has been caused by the exploitation and the increase of tourists. For the effective conservation and management on this issue, this study was conducted provide basic data. The sixteen study sites ($20{\times}20m$) were installed in the dominant Fagus engleriana stand and the base environment and vegetation were investigated. The Fagus engleriana stand was classified into two groups, The Fagus engleriana stand was classified into two groups, community A is Fagus engleriana-Sorbus amurensis and community B is Fagus engleriana-Acer pictum subsp. Mono by cluster analysis and community A were nothing signigicant by indicator species analysis. Community B were Eight species (Tsuga sieboldii, Camellia japonica, Dystaenia takesimana ect.) significant by indicator species analysis. The diameter class of 16cm to 25cm was 53.7% in population structure of Fagus engleriana, which was the highest and showed inverse J-distribution. Species diversity index (H') of investigated woody layer group ranged from 0.99 to 2.05 and that of under layer group ranged from 1.75~2.59. According to Non-metric Multidimensional Scaling (NMS) analysis, the woody layer was divided into community A developed in the region having relatively high sand content at high altitudes and community B formed at the place having relatively high clay content at low altitudes. Then this classification was significant through Multi-Response Permutation Procedures (MRPP) analysis. The distribution of understory vegetation through Detrended Correspondence Analysis (DCA) was induced by the silt content and cover degree of vegetation layer.

A Survey of Consumer's Consumption Characteristics of Environmental-Friendly Agricultural Products (EFAP) -Focused on Consumers in Discount Stores- (친환경농산물 소비행태 조사 -대형할인마트 고객을 중심으로-)

  • Lee, Yu-Si;Hong, Mi-Hyun;Ryu, Kyung;Kim, Ae-Jung;Ha, Sang-Do
    • Journal of Food Hygiene and Safety
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    • v.24 no.2
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    • pp.111-123
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    • 2009
  • We investigated the consumption inclinations of consumers for environmentally-friendly agricultural products (EFAP) for better production and distribution of EFAP. Consumer inclinations in large supermarkets from April 7th to 30th, 2008 were surveyed. Data were analyzed using the SPSSWIN 12.0 program. Results showed that 90.4% of consumers recognized EFAP and 76.4% of those who recognized the products had actually bought the products. Members of the "have purchased group" bought EFAP once a week because they believed these products were safe from hazards, such as pesticide. The amount spent on EFAP was less than 20% of the total food budget and the major consumed items were green vegetables and fruits. The sale location was mainly large supermarkets and agricultural cooperation outlets. Although many people were satisfied with EFAP from the viewpoint of nutritional and sensory qualities and safety compared with general agricultural products, they were notsatisfied with the price. Many consumers trusted that EFAP were safe and nutritional. Members of the "not purchased group" also trusted the nutritional and sensory qualities of EFAP and recognized the safety issue, but they were not satisfied with the price, compared with general agricultural products. Consequently, to succeed in the market, EFAP should maintain the confidence of the consumer while decreasing in price.

Moment Magnitude Determination Using P wave of Broadband Data (광대역 지진자료의 P파를 이용한 모멘트 규모 결정)

  • Hwang, Eui-Hong;Lee, Woo-Dong;Jo, Bong-Gon;Jo, Beom-Jun
    • Journal of the Korean Geophysical Society
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    • v.10 no.1
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    • pp.1-12
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    • 2007
  • A method to quickly estimate broadband moment magnitudes (Mwp) to warn regional and teleseismic tsunamigenic earthquakes is tested for application of the method to the different seismic observation environment. In this study, the Mwp is calculated by integrating far-field P-wave or pP-wave of vertical component of displacement seismograms in time domain from earthquakes, having magnitude greater than 5.0 and occurred in and around the Korean peninsula from 2000 to 2006. We carefully set up the size of the time window for the computations to exclude S wave phases and other phases following after the P wave phase. The P wave velocities and the densities from the averaged Korean crustal model are used in the computations. Instrumental correction was performed to remove dependency on the seismograph. The Mwp after the instrumental correction is about 0.1 greater than the Mwp before the correction. The comparison of our results to the those of foreign agencies such as JMA and Havard CMT catalogues shows a higher degree of similarity. Thus our results provide an effective tool to estimate the earthquake size, as well as to issue the necessary information to a tsunami warning system when the effective earthquake occurs around the peninsula.

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