• Title/Summary/Keyword: Environmental flows

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An Analysis of the Impacts of FDI Types on CO2 Emissions - Focus on Scale Effects and Technique Effects - (FDI 유형별 CO2 배출량에 미치는 영향 분석 - 규모효과와 기술효과를 중심으로 -)

  • Hwang, Yun-Seop;Park, Junghoon;Lee, Sang Whi
    • International Commerce and Information Review
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    • v.17 no.3
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    • pp.379-402
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    • 2015
  • The purpose of this study is to determine whether there is a significant difference in impacts decomposed into scale effects and technique effects on $CO_2$ emissions between Greenfield FDI and M&A FDI flows into Korean manufacturing sectors, ultimately leading to clarify the relationship between FDI and environmental pollution. To this end, the research constructed a simultaneous model to analyze coincidental relationship of influence and interactions between each variable. Archival data, spanning the 15 years period from 1995 to 2009, is industry-level panel data on 13 Korean manufacturing sectors, and it is empirically analyzed with three-stage least squares (3SLS) method. Key findings can be summarized into two parts. First of all, Greenfield FDI has a greater impact on increasing industrial gross output, resulting in more $CO_2$ emissions than M&A FDI through scale effects. Secondly, technique effects of FDI have a bigger impact on $CO_2$ emissions than scale effects, implying that this inflow of FDI into Korea contributes positively to the reduction of $CO_2$ emissions. These findings are expected to play a meaningful role in establishing FDI policies with consideration of the environment by giving the implication that different incentives for each FDI type should be considered to maximize the effect of environmental protection.

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Development and Assessment of Laboratory Testing Apparatus on Grouting Injection Performance (그라우팅 주입성능 실내실험 장비 개발 및 신뢰도 평가)

  • Jin, Hyunwoo;Ryu, Byunghyun;Lee, Jangguen
    • Journal of the Korean GEO-environmental Society
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    • v.17 no.10
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    • pp.23-31
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    • 2016
  • Grout is generally operated with low viscous material similar to water, but grout for micro crack with high viscous materials and high injection pressure is gradually increased under the development of underground and subsea space. In order to estimate grouting injection performance considering crack width, viscosity of grouting materials, and injection pressure, there should be a reliable standard laboratory testing method. In this paper, theoretical injection mechanisms of grouting materials are presented as radial and linear flows, and laboratory testing apparatus are introduced to simulate each flow case. Radial flow is simulated by using acrylic disk plates which are able to spread grouting material radially from the center of the disk plates, and linear flow is simulated by using stainless parallel plane plates which are able to spread grouting material linearly. Apparatus are consist of upper and lower plates and industrial films with different thickness are placed between plates in order to simulate various crack widths. Laboratory verification tests with these apparatus were conducted with tap water (1cP at $20^{\circ}C$) as an injection material. Through the laboratory testing results, the best laboratory testing method is recommended in order to estimate grouting injection performance.

Numerical Simulation on the Wind Ventilation Lane and Air Pollutants Transport due to Local Circulation Winds in Daegu Districts (대구지역의 국지순환풍의 환기경로 및 대기오염수송에 관한 수치모의)

  • Koo, Hyun-Suk;Kim, Hae-Dong
    • Journal of the Korean earth science society
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    • v.25 no.6
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    • pp.418-427
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    • 2004
  • Recently, urban planning with consideration of urban climate, represented by the concept of urban ventilation lane is widely practiced in many countries. The concept of urban ventilation lane is mainly aimed to improve the thermal comfort within urban area in summer season. It has also the aim to reduce the urban air pollution by natural cold air drainage flows which are to be intensified by a suitable alignment of buildings as well as use zonings based on scientific reasons. In this study, the prevailing wind ventilation lane of a local wind circulation and around Daegu for a typical summer days was investigated by using a numerical simulation. The transport of air pollutants by the local circulation winds was also investigated by using the numerical simulation model, the RAMS (Reasonal Atmospheric Model System).The domain of interest is the vicinity of Daegu metropolitan city (about 900 km2). The horizontal scale of the area is about 30 km. The simulations were conducted under a late spring synoptic condition with weak gradient wind and almost clear sky. From the numerical experiment, the following three conclusions were obtained: (1) The major wind passages of the local circulation wind generated by radiative cooling over the representative mountains of Daegu (Mt. Palgong and Mt. Ap) were found. The winds blow down along the valley axis over the eastern part of Daegu as a gravity flow during nighttime. (2) At the flatland, the winds blow toward the western part of Daegu through the city center. (3) As the results, the air pollutants were transported toward the western part of Daegu by the winds during nighttime.

The Spatial Inequalities in Education, Seoul (교육의 공간 불평등 연구)

  • Jung, Jae-Hun;Kim, Kyung-Min
    • Journal of the Economic Geographical Society of Korea
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    • v.17 no.2
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    • pp.385-401
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    • 2014
  • This research analyses spatial and temporal characteristics of the academic performances of high school students by using all 2,065,166 SAT scores for 3 years. The spatial inequalities in Seoul are analysed by DBMS and GIS. Based on three-year raw data of Korean SAT scores, the spatial and temporal characteristics of academic performances are scrutinized: 868,029 SAT scores cases of 2000 academic year on Novemver 17, 1999, 609,258 cases in 2005 academic year on November 17, 2004 and 587,890 cases in 2009 on November 13. The result shows that there are significant spatial disparities of the level of academic performance in Seoul by Gu level, also indicating that the disparities are getting wider over the course of time. The widening disparities by Gu level means that educational spatial inequality is intensified in spite of the increasing overall trend of academic performance of Seoul. It is also notable that disparities between regions are distinctive, while those in regions are not significant and sustained constant as time flows.

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Mesozooplankton Community Dynamics in Watan Stream, Yeonggwang, Korea (영광 와탄천의 중형동물플랑크톤 군집동태)

  • Lee, Dong-Ju;Kim, Say-Wa;Lee, Won-Choel
    • Korean Journal of Environmental Biology
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    • v.27 no.4
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    • pp.425-432
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    • 2009
  • Mesozooplankton dynamics were studied in Watan stream which flows into the Yellow Sea in Yeonggwang, Korea. Samples were collected at eight stations bimonthly during April 2006~February 2007. Mesozooplankton community was consisted of 45 taxa (8 cladocerans and 29 cope-pods). The abundance varied between the highest one ($31{\sim}127,587\;indiv.m^{-3}$) in October, and the lowest ($12{\sim}233\;indiv.m^-3$) in December. Diversity index showed to be the highest value in July (0.671) and the lowest one in August (0.368). A euryhaline species, Acartia hongi was dominant in brackish water stations (the highest abundance at $13.4^{\circ}C$ and 14.1 psu). In freshwater stations of the upstream, two cladoceran species of Polyphemus pediculus and Moina weismani occurred in high abundance in August. Dominant taxa of copepod were clustered to two or three groups mainly due to the difference of salinity gradients. Spatial distribution of mesozooplankton revealed to be determined by salinity gradients which were affected by opening and closing of the artificial dam in Watan stream.

A GRAVITY STUDY OF THE TRIASSIC VALLEY IN SOUTHERN CONNECTICUT

  • Chang, Chung Chin
    • Economic and Environmental Geology
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    • v.2 no.2
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    • pp.1-35
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    • 1969
  • The structure and geologic history of the Triassic basin in southern Connecticut have been interpreted by using gravimetric data. A gravity survey of 800 gravity stations was made by the U.S. Geological Survey in the southern Connecticut area. The resulting data were reduced by the Bouguer method and then plotted and contoured along with the generalized geology. Residual gravity maps were prepared by different methods to obtain the most plausible agreement with the known geology of the area. Seven gravity profiles across the basin are presented to show the distribution of the Triassic deposits that could produce the measured anomalies. It is concluded that the basin was formed by successive step faulting in the late Triassic period and that the sediments accumulated progressively in this basin. The deepest portion of the basin is located in the middle of the present Triassic belt and reaches a depth of about 2 miles below the surface. The data also appear to indicate the possible source areas for the basalt which at present forms the lava flows, sills, and dikes exposed in the Cheshire and Gaillard regions. The information concerning the tectonic history of the Connecticut Triassic Valley aids considerably in establishing the geologic history of the Appalachians in late Triassic time.

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Improvement of Building-Construction Algorithm for Using GIS data and Analysis of Flow and Dispersion around Buildings (GIS 자료사용을 위한 건물 구축 알고리즘 개선 및 건물 주변 흐름과 확산 분석)

  • Kwon, A-Rum;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
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    • v.30 no.6
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    • pp.731-742
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    • 2014
  • In this study, we developed a new algorithm which can construct model buildings used as a surface boundary in numerical models using GIS with latitudinal and longitudinal information of building vertices. The algorithm established the outer boundary of a building first, by finding segments passing neighboring two vertices of the building and connecting the segments. Then, the algorithm determined the region inside the outer boundary as the building. The new algorithm overcame the limit that the algorithm developed in the previous study had in constructing concave buildings. In addition, the new algorithm successfully constructed a building with complicated shape. To investigate effects of the modification in building shape caused by the building-construction algorithm on flows and pollutant dispersion around buildings, a computational fluid dynamics model was used and three kinds of building type were considered. In the downwind region, patterns in flow and pollutant dispersion were little affected by the modification in building shape caused. However, because of reduction in air space resulted from the building-shape modification, vortex structure was not resolved or smaller vortex was resolved near the buildings. The changes in flow pattern affected dispersion patterns of scalar pollutants emitted around the buildings.

Evaluation of the Safty for the Disposal of High-level Nuclear Waste in the Granite (화강암지역에 고준위 원자력 폐기물 처리에 대한 안정성 평가)

  • Oh, Chang Whan
    • Economic and Environmental Geology
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    • v.29 no.2
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    • pp.215-225
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    • 1996
  • All the radionuclides in high-level nuclear waste will decay to harmless levels eventually but for some radionuclides decay is so slow that their radiation remains dangerous for times on the order of tens or hundreds of thousands of years. At the present time, the most favorite disposal plan for high-level radioactive waste is a mined geological disposal in which canister enclosing stable solid form of radioactive waste is placed in mined cavities locating hundred meters below the surface. The chief hazard in such disposal is dissolution of radionuclides from the waste in the groundwater that will eventually carry the dissolved radionuclides to surface environments. The hazard from possible escape of the radionuclides through groundwater can be delayed by engineered and geologic barriers. The engineered barriers can become useless by unexpected geologic catastrophe such as volcanism, earthquake, and tectonic movement and by fraudulent work such as careless construction, improperly welded canisters within the first few decades or centuries. As a result, dangerously radioactive waste which is still intensively radioactive is directly exposed to attack by moving groundwater. All the more, it is almost impossible to control repositories for times more than 10,000 years. Therefore, naturally controlled geologic, barriers whose properties will not be changed within 10,000 years are important to guarantee the safety of repositories of high-level radioactive waste. In Sweden and France, the suitability of granite for the mined geological disposal of high-level waste has been studied intensively. According to the research in Sweden and France, granites has the following physio-chemical characteristics which can delay the transportation of radionuclide by groundwater. First, the permeabilities of granites decreases as the depth increases and is $10^{-8}{\sim}10^{-12}m/s$ at depth below 300 m. Second, groundwater at depth below 300 m has pH=7-9 and reducing condition (Eh=-0.1~0.4). This geochemical condition is desirable to prevent both canister and solid waste from corrosion. Third most radionuclides are not transported by low solubilities and some radionuclide with high solubility such as Cs and Sr are retarded by absorption of geologic media through which ground water flows. Therefore, if high-level waste is disposed at depth below 300 m in the granite body which has a low permeability and is geologically stable more than 10,000 years, the safety of repositories from the hazard due to radionuclide escape can guaranteed for more than 10,000 years.

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Analyses on Environment-friendliness of Waterproof Materials Based on Fish Toxicity Test (어독성 실험에 따른 방수재 친환경 특성 분석)

  • Kim, Sung-Kyun;Woo, Ji-Keun;Lee, Im-Gyu;Yoo, Hy-Ein;Jeong, Jae-Wook
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.1
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    • pp.57-68
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    • 2010
  • The purpose of this study is to analyze the characteristics of environment-friendliness of waterproof materials based on comprehensive experiments on waterproofness in terms of coefficients of permeability, harmfulness of waterproof materials and fish toxicity of Oryzias latipes mortality to verify eco-toxicity of each method of construction and waterproof material, which are to be applied by taking eco-toxicity into account when building ecological flows in upper areas on natural and artificial grounds. As a result, the following conclusions have been reached in this study: 1. In regard of the harmfulness analyzed, each material showed a different result of analytical value in each lab tank. Compared to input water, pH, COD, SS, T-P, and T-N values increased a little, but DO value decreased. The value of turbidity analyzed independent of the water quality standard of aquatic ecosystem set forth by the Ministry of Environment increased a little compared to the value in input water. 2. In the experiment of fish toxicity, compacted quicklime, cement fluid waterproof material, cement mortar waterproof material and bentonite powder were found to have 100% of fish mortality, respectively, and membrane waterproof material showed 83.3% of mortality, indicating strong fish toxicity. Improved asphalt sheet (63.3%) and synthetic rubber sheet (53.3%) were analyzed to have medium fish toxicity, while bentonite sheet (6.7%), Hwang-toh (6.7%) and clay (3.3%) showed relatively lower mortality and fish toxicity. 3. Regarding the analysis on waterproofness in terms of the coefficient of permeability of each waterproof material, improved asphalt sheet, synthetic rubber sheet, membrane waterproof material, cement fluid and mortar waterproof material and bentonite sheet were found impervious in case no leakage takes place in construction. Bentonite powder was found practically impervious based on the analytical results from the experiment done in compliance with weight ratios. So were the clay and Hwang-toh from the experimental results. To sum up such results as found in the experiment mentioned so far, the values of harmfulness and waterproofness analyzed were different in each lab tank, but there was absolutely little correlation with the mortality gained from the experiment on fish toxicity. In the experiment of fish toxicity, environment-friendly waterproof materials were analyzed, and it was found that clay, Hwang-toh and bentonite sheet are highly environment-friendly. In contrast, synthetic rubber and improved asphalt sheets were found to have medium-level environment-friendliness. Also, membrane water-proof materials, compacted quicklime, cement fluid and mortar waterproof material and bentonite powder were analyzed to have low environment-friendliness.

The Effects of Mixer Geometry on Hydraulic Turbulence : Computational Modeling (3-D 전산유체를 이용한 급속혼화조 형상에 따른 난류 유동장 연구)

  • Park, No-Suk;Kim, Sung-Hoon;Park, Heekyung
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.7
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    • pp.1173-1182
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    • 2000
  • The rapid mixing process has been considered as an important step in water treatment. Since the coagulant dispersion into raw water by rapid mixer can influence on the flocculation and filtration efficiency, many researchers have developed various devices and mixing methodologies. Until now, they focused attention on only coagulant dose, pH. rotating velocity and G value but overlooked the real turbulent flow and mixer geometry in rapid mixer. Therefore this paper questions the significance of turbulent flows in rapid mixer and focuses on the analysis of turbulent fluid in various mixer geometry with CFD(Computational Fluid Dynamics). The results of the jar-tests using various geometries indicate that the turbidity removal rate in a circular jar without baffle is higher than that of a circular with baffle. And the turbidity removal rate in Hudson jar is also founded to be higher than in the circular jar with baffle. The CFD simulation of velocity fields in jar demonstrates that the differences of removal rates among the various geometries are largely due to the formation of the different turbulent fluids fields with different geometries.

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