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Water Balance and Pollutant Load Analyses according to LID Techniques for a Town Development (도시 개발 전·후 LID 기법 적용에 따른 물수지 및 오염부하 변동 특성)

  • Park, Ji-Young;Lim, Hyun-Man;Lee, Hae-In;Yoon, Young-Han;Oh, Hyun-Je;Kim, Weon-Jae
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.11
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    • pp.795-802
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    • 2013
  • According to the increase of impervious area due to the town development, the rate of infiltration generally lessens and that of runoff rises during wet weather events. And it is concerned that its impacts on water quality for the downstream water bodies due to the change of rainfall runoff patterns may also increase. To cope with these issues, LID (Low Impact Development) techniques which try to maintain the characteristics of rainfall runoff regardless of the town development have been introduced actively. However, the behaviors of each LID technique for rainfall runoff and pollutant loads is not understood sufficiently. In this study, considering the applications of some LID techniques, several sets of simulations using a distributed rainfall runoff model, SWMM-LID, have been conducted for D town whose development is progressing. As the results of the simulations, the rates of infiltration/storage have been decreased from 78% in the case before the town development to 15% after the development and increased again by 24% with LID techniques such as porous pavement, rain barrel and rain garden. The rates of runoff have been increased more than three times from 20% in the case before the development to 74% after the development, and they have also been decreased to 66% by the adoption of LID techniques. It has been simulated that porous pavement is more effective than others in the view point of the reduction of runoff and rain barrel is more attractive for the management of pollutant loads (TSS, BOD, COD, T-N and T-P). Therefore, if some LID techniques should be selected for the a new town, it could be concluded that some techniques with better infiltration functions are recommendable for the control of runoff, and ones with larger storage functions for the management of pollutant loads.

Economic Impact of the Tariff Reform : A General Equilibrium Approach (관세율(關稅率) 조정(調整) 경제적(經濟的) 효과분석(效果分析) : 일반균형적(一般均衡的) 접근(接近))

  • Lee, Won-yong
    • KDI Journal of Economic Policy
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    • v.12 no.1
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    • pp.69-91
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    • 1990
  • A major change in tariff rates was made in January 1989 in Korea. The benchmark tariff rate, which applies to about two thirds of all commodity items, was lowered to 15 percent from 20 percent. In addition, the variation in tariff rates among different types of commodities was reduced. This paper examines the economic impact of the tariff reform using a multisectoral general equilibrium model of the Korean economy which was introduced by Lee and Chang(1988), and by Lee(1988). More specifically, this paper attempts to find the changes in imports, exports, domestic production, consumption, prices, and employment in 31 different sectors of the economy induced by the reform in tariff rates. The policy simulations are made according to three different methods. First, tariff changes in industries are calculated strictly according to the change in legal tariff rates, which tend to over-estimate the size of the tariff reduction given the tariff-drawback system and tariff exemption applied to various import items. Second, tariff changes in industries are obtained by dividing the estimated tariff revenues of each industry by the estimated imports for that industry, which are often called actual tariff rates. According to the first method, the import-weighted average tariff rate is lowered from 15.2% to 10.2%, while the second method changes the average tariff rate from 6.2% to 4.2%. In the third method, the tariff-drawback system is internalized in the model. This paper reports the results of the policy simulation according to all three methods, comparing them with one another. It is argued that the second method yields the most realistic estimate of the changes in macro-economic variables, while the third method is useful in delineating the differences in impact across industries. The findings, according to the second method, show that the tariff reform induces more imports in most sectors. Garments, leather products, and wood products are those industries in which imports increase by more than 5 percent. On the other hand, imports in agricultural, mining and service sectors are least affected. Domestic production increases in all sectors except the following: leather products, non-metalic products, chemicals, paper and paper products, and wood-product industries. The increase in production and employment is largest in export industries, followed by service industries. An impact on macroeconomic variables is also simulated. The tariff reform increases nominal GNP by 0.26 percent, lowers the consumer price index by 0.49 percent, increases employment by 0.24 percent, and worsens the trade balance by 480 million US dollars, through a rise in exports of 540 million US dollars and a rise in imports of 1.02 billion US dollars.

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Seismic Data Processing and Inversion for Characterization of CO2 Storage Prospect in Ulleung Basin, East Sea (동해 울릉분지 CO2 저장소 특성 분석을 위한 탄성파 자료처리 및 역산)

  • Lee, Ho Yong;Kim, Min Jun;Park, Myong-Ho
    • Economic and Environmental Geology
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    • v.48 no.1
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    • pp.25-39
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    • 2015
  • $CO_2$ geological storage plays an important role in reduction of greenhouse gas emissions, but there is a lack of research for CCS demonstration. To achieve the goal of CCS, storing $CO_2$ safely and permanently in underground geological formations, it is essential to understand the characteristics of them, such as total storage capacity, stability, etc. and establish an injection strategy. We perform the impedance inversion for the seismic data acquired from the Ulleung Basin in 2012. To review the possibility of $CO_2$ storage, we also construct porosity models and extract attributes of the prospects from the seismic data. To improve the quality of seismic data, amplitude preserved processing methods, SWD(Shallow Water Demultiple), SRME(Surface Related Multiple Elimination) and Radon Demultiple, are applied. Three well log data are also analysed, and the log correlations of each well are 0.648, 0.574 and 0.342, respectively. All wells are used in building the low-frequency model to generate more robust initial model. Simultaneous pre-stack inversion is performed on all of the 2D profiles and inverted P-impedance, S-impedance and Vp/Vs ratio are generated from the inversion process. With the porosity profiles generated from the seismic inversion process, the porous and non-porous zones can be identified for the purpose of the $CO_2$ sequestration initiative. More detailed characterization of the geological storage and the simulation of $CO_2$ migration might be an essential for the CCS demonstration.

The PRISM-based Rainfall Mapping at an Enhanced Grid Cell Resolution in Complex Terrain (복잡지형 고해상도 격자망에서의 PRISM 기반 강수추정법)

  • Chung, U-Ran;Yun, Kyung-Dahm;Cho, Kyung-Sook;Yi, Jae-Hyun;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.2
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    • pp.72-78
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    • 2009
  • The demand for rainfall data in gridded digital formats has increased in recent years due to the close linkage between hydrological models and decision support systems using the geographic information system. One of the most widely used tools for digital rainfall mapping is the PRISM (parameter-elevation regressions on independent slopes model) which uses point data (rain gauge stations), a digital elevation model (DEM), and other spatial datasets to generate repeatable estimates of monthly and annual precipitation. In the PRISM, rain gauge stations are assigned with weights that account for other climatically important factors besides elevation, and aspects and the topographic exposure are simulated by dividing the terrain into topographic facets. The size of facet or grid cell resolution is determined by the density of rain gauge stations and a $5{\times}5km$ grid cell is considered as the lowest limit under the situation in Korea. The PRISM algorithms using a 270m DEM for South Korea were implemented in a script language environment (Python) and relevant weights for each 270m grid cell were derived from the monthly data from 432 official rain gauge stations. Weighted monthly precipitation data from at least 5 nearby stations for each grid cell were regressed to the elevation and the selected linear regression equations with the 270m DEM were used to generate a digital precipitation map of South Korea at 270m resolution. Among 1.25 million grid cells, precipitation estimates at 166 cells, where the measurements were made by the Korea Water Corporation rain gauge network, were extracted and the monthly estimation errors were evaluated. An average of 10% reduction in the root mean square error (RMSE) was found for any months with more than 100mm monthly precipitation compared to the RMSE associated with the original 5km PRISM estimates. This modified PRISM may be used for rainfall mapping in rainy season (May to September) at much higher spatial resolution than the original PRISM without losing the data accuracy.

Change of Carbon Fixation and Economic Assessment according to the Implementation of the Sunset Provision (도시공원 일몰제에 의한 탄소고정량과 경제성 분석에 대한 연구)

  • Choi, Jiyoung;Lee, Sangdon
    • Ecology and Resilient Infrastructure
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    • v.7 no.2
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    • pp.126-133
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    • 2020
  • In accordance with the implementation of the sunset provision to cancel the designations of urban park sites that remained unexecuted for a prolonged period until 2020, the park sites in the city center, which account for 90% of the long-term unexecuted urban facilities subjected to the provision, are currently on the verge of development. The total area of the 204 park sites that will disappear in Seoul as a result of this provision is 95 ㎢; moreover, 116 of these are privately-owned. It is expected that the possible changes in the use of these park sites could result in reckless development and reduction of green space, which would ultimately affect the ecosystem. This study applied the InVEST model to calculate the changes in the fixed carbon amount before and after the implementation of the sunset provision to estimate the economic value of these changes. The study focused on Jongno-gu in Seoul because it has the most unexecuted park sites subjected to the lifting of the designation. The research findings show that the fixed carbon amount provided by the unexecuted park sites in Jongno-gu was 374,448 mg, prior to the implementation of the sunset provision; however, the amount was estimated to decrease by 18% to 305,564 mg after its execution. When calculated in terms of average value of the real carbon price, this translated into a loss of approximately 700 million won. In addition, considering the social costs including both climate change and the impact on the ecosystem, an economic loss of approximately 98 billion won was projected. This study is meaningful because its predictions are based on the estimation of fixed carbon amount according to the implementation of the sunset provision in Jongno-gu and scientifically calculates the value of ecological services provided by the parks in the city. This study can serve not only as a basis during the decision-making process for policies related to ecosystem conservation and development, but also as an evidentiary material for the compensation of privately-owned land that is designated as urban park sites and was unexecuted for a prolonged period.

External Gravity Field in the Korean Peninsula Area (한반도 지역에서의 상층중력장)

  • Jung, Ae Young;Choi, Kwang-Sun;Lee, Young-Cheol;Lee, Jung Mo
    • Economic and Environmental Geology
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    • v.48 no.6
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    • pp.451-465
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    • 2015
  • The free-air anomalies are computed using a data set from various types of gravity measurements in the Korean Peninsula area. The gravity values extracted from the Earth Gravitational Model 2008 are used in the surrounding region. The upward continuation technique suggested by Dragomir is used in the computation of the external free-air anomalies at various altitudes. The integration radius 10 times the altitude is used in order to keep the accuracy of results and computational resources. The direct geodesic formula developed by Bowring is employed in integration. At the 1-km altitude, the free-air anomalies vary from -41.315 to 189.327 mgal with the standard deviation of 22.612 mgal. At the 3-km altitude, they vary from -36.478 to 156.209 mgal with the standard deviation of 20.641 mgal. At the 1,000-km altitude, they vary from 3.170 to 5.864 mgal with the standard deviation of 0.670 mgal. The predicted free-air anomalies at 3-km altitude are compared to the published free-air anomalies reduced from the airborne gravity measurements at the same altitude. The rms difference is 3.88 mgal. Considering the reported 2.21-mgal airborne gravity cross-over accuracy, this rms difference is not serious. Possible causes in the difference appear to be external free-air anomaly simulation errors in this work and/or the gravity reduction errors of the other. The external gravity field is predicted by adding the external free-air anomaly to the normal gravity computed using the closed form formula for the gravity above and below the surface of the ellipsoid. The predicted external gravity field in this work is expected to reasonably present the real external gravity field. This work seems to be the first structured research on the external free-air anomaly in the Korean Peninsula area, and the external gravity field can be used to improve the accuracy of the inertial navigation system.

A Study on the ICAO international aviation safety policy, a change of paradigm and the government response to the direction (ICAO 국제항공안전정책 패러다임의 변화 분석과 우리나라 신국제항공안전정책 검토)

  • Chang, Man-Heui;Hwang, Ho-Won
    • The Korean Journal of Air & Space Law and Policy
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    • v.28 no.1
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    • pp.73-96
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    • 2013
  • ICAO's Universal Safety Oversight Audit Programme (USOAP) was initially launched in January 1995, in response to widespread concerns about the adequacy of aviation safety oversight around the world. The recent reduction in aircraft accidents and effective role that is evaluated on the basis of these results, and in 2013 the existing 'snapshot approach' to 'regular monitoring system (USOAP-Continuous Monitoring Approach)' was converted to. ICAO aviation safety assessment of the state in today's international community 'aviation safety credibility' as objective indicators to judge the enormous impact on the aviation industry, the state is not satisfactory, especially if the results of the evaluation and expansion of code-share airline ban, reduced international air transit passengers, including premium increases business and economic penalties should. In addition, ICAO implementation of the existing laws and regulations(Prescriptive Approach), but based on the Risk-based prevention model, Proactive Approach introduced the concept of aviation safety system, including international aviation safety policy has been to switch paradigms. This new ICAO international aviation safety policy also applies to the Government of the Republic of Korea in line with the aviation safey policies have changed. In particular, the systematic implementation of safety management for the existing laws and regulations in the center of the safety oversight system of risk-based introduction of the concept of proactive safety management, and According to international standards ICAO aviation service providers operate their own Safety Management System was set out in Aviation Law ever. In addition, the aviation safety is at the center of the field of the safety of aircraft operations and maintenance for the promotion is promoting various safety policies. This new paradigm shift in the international aviation safety policy in line with our state in the international community with the most exemplary aviation safety system firmly established itself as a model, the Government will strengthen the competitiveness of our aviation plans to support. To do this, the government, airlines, aviation officials try all the practical effect would be expected.

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Anti-inflammatory effects of Ishige sinicola ethanol extract in LPS-induced RAW 264.7 cell and mouse model (LPS로 유도된 RAW 264.7 Cell과 마우스 모델에 대한 넓패(Ishige sinicola) 에탄올 추출물의 항염증 효과)

  • Kim, Ji-Hye;Kim, Min-Ji;Kim, Koth-Bong-Woo-Ri;Park, Sun-Hee;Cho, Kwang-Su;Kim, Go-Eun;XU, Xiaotong;Lee, Da-Hye;Park, Ga-Ryeong;Ahn, Dong-Hyun
    • Food Science and Preservation
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    • v.24 no.8
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    • pp.1149-1157
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    • 2017
  • Inflammation is the first response of the immune system to infection or irritation in our body. The use of medicinal plants has been widely applied as an alternative source for drug development. One of marine natural resources, the anti-inflammatory effect of Ishige sinicola ethanol extract (ISEE), was evaluated by using LPS-induced RAW 264.7 cell and mice model. As a result, the production of nitric oxide (NO) and pro-inflammatory cytokines (IL-6, IL-$1{\beta}$, TNF-${\alpha}$) were inhibited with increasing concentration of ISEE without any cytotoxicity. Furthermore, ISEE suppressed the expression of not only inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor-kappa B (NF-${\kappa}B$) p65, and mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK) 1/2, p38, and c-Jun N-terminal kinase (JNK) in a dose-dependent manner. In mice ear edema test, the formation of edema was reduced at the highest dosage of ISEE and the reduction of the number of infiltrated mast cells was observed in histological analysis. These results indicate that ISEE has a potent anti-inflammatory activity and can be used as a pharmaceutical material for many kinds of inflammatory disease.

Analysis of Climate Change Researches Related to Water Resources in the Korean Peninsula (한반도 수자원분야 기후변화 연구동향 분석)

  • Lee, Jae-Kyoung;Kim, Young-Oh;Kang, Noel
    • Journal of Climate Change Research
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    • v.3 no.1
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    • pp.71-88
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    • 2012
  • The global warming is probably the most significant issue of concern all over the world and according to the report published by the Intergovernmental Panel on Climate Change (IPCC), the average temperature and extent of global warming around the globe have been on the rise and so have the uncertainty for the future. Such effects of global warming have adverse effects on basic foundation of the mankind in numerous ways and water resource is no exception. The researches on water resources assessment for climate change are significant enough to be used as the preliminary data for researches in other fields. In this research, a total of 124 peer-reviewed publications and 57 reports on the subject of research on climate change related to water resources, that has been carried out so far in Korea has been reviewed. The research on climate change in Korea (inclusive of the peer-reviewed articles and reports) has mainly focused on the future projection and assessment. In the fields of hydrometeorology tendency and projection, the analysis has been carried out with focus on surface water, flood, etc. for hydrological variables and precipitation, temperature, etc. for meteorological variables. This can be attributed to the large, seasonal deviation in the amount of rainfall and the difficulty of water resources management, which is why, the analysis and research have been carried out with focus on those variables such as precipitation, temperature, surface water, flood, etc. which are directly related to water resources. The future projection of water resources in Korea may differ from region to region; however, variables such as precipitation, temperature, surface water, etc. have shown a tendency for increase; especially, it has been shown that whereas the number of casualties due to flood or drought decreases, property damage has been shown to increase. Despite the fact that the intensity of rainfall, temperature, and discharge amount are anticipated to rise, appropriate measures to address such vulnerabilities in water resources or management of drainage area of future water resources have not been implemented as yet. Moreover, it has been found that the research results on climate change that have been carried out by different bodies in Korea diverge significantly, which goes to show that many inherent uncertainties exist in the various stage of researches. Regarding the strategy in response to climate change, the voluntary response by an individual or a corporate entity has been found to be inadequate owing to the low level of awareness by the citizens and the weak social infrastructure for responding to climate change. Further, legal or systematic measures such as the governmental campaign on the awareness of climate change or the policy to offer incentives for voluntary reduction of greenhouse gas emissions have been found to be insufficient. Lastly, there has been no case of any research whatsoever on the anticipated effects on the economy brought about by climate change, however, there are a few cases of on-going researches. In order to establish the strategy to prepare for and respond to the anticipated lack of water resources resulting from climate change, there is no doubt that a standardized analysis on the effects on the economy should be carried out first and foremost.

Examining the Relationship Among Restaurant Brand Relationship Quality, Attribution, and Emotional Response After Service Failure Experience (서비스 실패 경험 후 레스토랑 브랜드 품질, 귀인 및 감정반응 관계분석)

  • Jang, Gi-Hwa;Song, Soo-Ik;Oh, Sung-Cheon
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.1120-1133
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    • 2018
  • The purpose of this study is to validate the failure attribution factors affecting emotional changes after a failed service by local restaurant users, and the relapse effects of the perceived failure of a customer's brand relationship. In this study, the implications of this study can be divided into the null theory and the homogenous theory, in which the study of the relationship between individual belief that influences the null theory and the post-gender emotional response is minimal. The independence of the crash response (angerous VS compassion) has been equally validated as building a belief-gathering-emotion three-step model. First, emotional BRQ (intimate and love) has a reduction effect on controllable geeks, and behavioral BRQ (relative existence) has an extended effect on controllable geeks. From a management perspective, restaurant managers should be less aware of the repeatability of a customer's service failure and call for customer sympathy. Integratedly, restaurant managers must control the customer's perception of service failure and restore the impact of the customer's BRQ on emotional reactions. A variety of service recovery measures should be established and the cerumen should be controlled. In addition, since BRQs have different effects on anger and sympathy (extended VS), different service failure recovery plans should be presented depending on the characteristics of the customer BRQ. For example, measures such as monetary compensation or fair dealing, emotional distribution to close and loving customers, and persuasion of reciprocal benefits to interdependent customers should be developed according to circumstances. This study explored the effectiveness of the geeks after a service failure and has limitations that do not take into account the various regulatory factors in the BRQ-return-Empression process. Thus, in further studies, the effects of adjusting service failure strength should be considered and a more complete model should be built.