• Title/Summary/Keyword: ozone depletion

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Effects of Enhanced Ultraviolet-B Radiation on Plants (오존층 파괴에 의한 자외선 증가가 식물에 미치는 영향)

  • Hak Yoon Kim;Moon Soo Cho
    • Journal of Bio-Environment Control
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    • v.10 no.3
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    • pp.197-206
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    • 2001
  • The depletion of stratospheric ozone is regarded as a major environmental threat to plant growth and ecosystem. The ozone depletion has caused plants to be exposed to an increased penetration of solar ultraviolet-B (UV-B) radiation in the 280-320 nm wavelength range. Enhanced UV-B radiation may have influence on plants biological functions in many aspects including inhibition of photosynthesis, DNA damage, lipid peroxidation, changes in morphology, phenology, and biomass accumulation. To cope with the damage by UV radiation, plants have evolved to have protective mechanisms, such as photorepair, accumulation of UV-absorbing compounds, leaf thickening and activation of antioxidative enzymes. The objective of this review is to address the effects of enhanced UV-B on plant growth, UV-B action mechanisms and protection and protection mechanisms in plants.

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Development of the Assessment Framework for the Environmental Impacts in Construction

  • Hong, Tahoon;Ji, Changwoon;Jeong, Kwangbok;Park, Joowan
    • Journal of Construction Engineering and Project Management
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    • v.3 no.3
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    • pp.1-9
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    • 2013
  • Environmental problems like global warming have now become important issues that should be considered in all industries, including construction. In South Korea, many studies have been conducted to achieve the government's goals of reduction in environmental impacts. However, the research on buildings has only focused on CO2 emission as a research target despite the fact that other environmental impacts resulting from ozone depletion and acidification should also be considered, in addition to global warming. In this regard, this study attempted to propose assessment criteria and methods to evaluate the environmental performance of the structures from various aspects. The environmental impact category can be divided into global impacts, regional impacts, and local impacts. First, global impacts include global warming, ozone layer depletion, and abiotic resource depletion, while regional impacts include acidification, eutrophication, and photochemical oxidation. In addition, noise and vibration occurring in the building construction phase are defined as local impacts. The evaluation methods on the eight environmental impacts will be proposed after analyzing existing studies, and the methods representing each environmental load as monetary value will be presented. The methods presented in this study will present benefits that can be obtained through green buildings with a clear quantitative assessment on structures. Ultimately, it is expected that if the effects of green buildings are clearly presented through the findings of this study, the greening of structures will be actively expanded.

Updated Trends of Stratospheric Ozone over Seoul (서울 상공의 최신 성층권 오전 변화 경향)

  • Kim, Jhoon;Cho, Hi-Ku;Lee, Yun-Gon;Oh, Sung Nam;Baek, Seon-Kyun
    • Atmosphere
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    • v.15 no.2
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    • pp.101-118
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    • 2005
  • Atmospheric ozone changes temporally and spatially according to both anthropogenic and natural causes. It is essential to quantify the natural contributions to total ozone variations for the estimation of trend caused by anthropogenic processes. The aims of this study are to understand the intrinsic natural variability of long-term total ozone changes and to estimate more reliable ozone trend caused by anthropogenic ozone-depleting materials. For doing that, long-term time series for Seoul of monthly total ozone which were measured from both ground-based Dobson Spectrophotometer (Beck #124)(1985-2004) and satellite TOMS (1979-1984) are analyzed for selected period, after dividing the whole period (1979~2004) into two periods; the former period (1979~1991) and the latter period (1992~2004). In this study, ozone trends for the time series are calculated using multiple regression models with explanatory natural oscillations for the Arctic Oscillation(AO), North Atlantic Oscillation(NAO), North Pacific Oscillation(NPO), Pacific Decadal Oscillation(PDO), Quasi Biennial Oscillation(QBO), Southern Oscillation(SO), and Solar Cycle(SC) including tropopause pressure(TROPP). Using the developed models, more reliable anthropogenic ozone trend is estimated than previous studies that considered only QBO and SC as natural oscillations (eg; WMO, 1999). The quasi-anthropogenic ozone trend in Seoul is estimated to -0.12 %/decade during the whole period, -2.39 %/decade during the former period, and +0.10 %/decade during the latter period, respectively. Consequently, the net forcing mechanism of the natural oscillations on the ozone variability might be noticeably different in two time intervals with positive forcing for the former period (1979-1991) and negative forcing for the latter period (1992-2004). These results are also found to be consistent with those analyzed from the data observed at ground stations (Sapporo, Tateno) of Japan. In addition, the recent trend analyses for Seoul show positive change-in-trend estimates of +0.75 %/decade since 1997 relative to negative trend of -1.49 %/decade existing prior to 1997, showing -0.74 %/decade for the recent 8-year period since 1997. Also, additional supporting evidence for a slowdown in ozone depletion in the upper stratosphere has been obtained by Newchurch et al.(2003).

Relationship between Atmospheric Transmissivity and Air Pollution in Korea (우리나라의 대기투과율과 대기오염과의 관계)

  • Lee, Hyup-Hee;Kim, Young-Seop;Han, Young-Ho
    • Journal of Environmental Science International
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    • v.4 no.5
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    • pp.52-52
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    • 1995
  • The temporal and spatial distribution of atmospheric transmissivity and depletion rate of solar radiation are investigated, and are compared to the concentration of several components of air pollution. The length of the data span is 11 years from 1983 to 1993. The data of radiation and sunshine rate recorded at 20 meteorological standard stations were used, and in order to investigate a relationship between the depletion rate of solar radiation and air pollution, the concentration data of air pollution observed in Seoul, Pusan, Taegu, Taejon and Kwangju were compiled from 1991 to 1993. Regression coefficient a and b vary from 0.100 to 0.209, from 0.464 to 0.691, and their means are 0.163 and 0.533, respectively. Climatological atmospheric transmissivity is ranged from 0.68 to 0.83, and its mean is 0.75. Atmospheric transmissivity is relatively low in Pusan, Taejon, Kwangju and Inchon which have large population and are highly industrialized. However, that in Chinju, Mokpo, Cheju and Sosan appears to be large compared to the aforementioned stations. Insolation rate of clear days varies from 0.71 to 0.58, and its mean is 0.63. Insolation rate of Kangnung and Chinju are higher than those of Seoul and Pusan by 5%. From the correlation coefficients between depletion rate of solar radiation and air pollution concentration, the most significant factors related to the depletion rate of solar radiation is appeared to be TSP followed by $SO_2$. Ozone shows a negative correlation, End $NO_2$ does not show a obvious correlation with the depletion rate of solar radiation.

Relationship between Atmospheric Transmissivity and Air Pollution in Korea (우리나라의 대기투과율과 대기오염과의 관계)

  • Lee, Hyup-Hee;Kim, Young-Seop;Han, Young-Ho
    • Journal of Environmental Science International
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    • v.4 no.5
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    • pp.437-446
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    • 1995
  • The temporal and spatial distribution of atmospheric transmissivity and depletion rate of solar radiation are investigated, and are compared to the concentration of several components of air pollution. The length of the data span is 11 years from 1983 to 1993. The data of radiation and sunshine rate recorded at 20 meteorological standard stations were used, and in order to investigate a relationship between the depletion rate of solar radiation and air pollution, the concentration data of air pollution observed in Seoul, Pusan, Taegu, Taejon and Kwangju were compiled from 1991 to 1993. Regression coefficient a and b vary from 0.100 to 0.209, from 0.464 to 0.691, and their means are 0.163 and 0.533, respectively. Climatological atmospheric transmissivity is ranged from 0.68 to 0.83, and its mean is 0.75. Atmospheric transmissivity is relatively low in Pusan, Taejon, Kwangju and Inchon which have large population and are highly industrialized. However, that in Chinju, Mokpo, Cheju and Sosan appears to be large compared to the aforementioned stations. Insolation rate of clear days varies from 0.71 to 0.58, and its mean is 0.63. Insolation rate of Kangnung and Chinju are higher than those of Seoul and Pusan by 5%. From the correlation coefficients between depletion rate of solar radiation and air pollution concentration, the most significant factors related to the depletion rate of solar radiation is appeared to be TSP followed by $SO_2$. Ozone shows a negative correlation, End $NO_2$ does not show a obvious correlation with the depletion rate of solar radiation.

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A Study on Characteristics of HFC-l34a and OS-l2a Refrigerant in Automobile Air-Conditioning System (자동차 에어컨용 냉매인 HFC-134a와 OS-12a의 성능 특성에 관한 연구)

  • 이종인;하옥남
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.3
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    • pp.136-142
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    • 2002
  • HFC-134a is currently used as the refrigerant in automobile air-conditioner, replacing the ozone depleting refrigerant CFC-12. Although HFC-l34a has no ozone depletion potential, it has a relatively high global warming potential, approximately 1300 tins that of CO$_2$ over a 100 year time horizon. Therefore, HFC- l34a does not seem to be a perfect alternative refrigerant due to high GWP. For this reason, non-azeotrope refrigerant mixture have been proposed as a long-term and drop-in alternative to HFC-l34a in the automobile air-conditioning system which has variable operating conditions with changes in RPM and pressure ratio. In this study,OS-l2a of which thermodynamic properties are similar to those of HFC-l34a is selected among the mixed refrigerant. HFC-l34a and OS-l2a are examined experimently by the performance test in the same automobile air-conditioning system.

The Survey for the alternate refrigerants of a train HVAC considering the restriction for "Environment-Friendly" (친환경 규제에 따른 철도차량 에어컨 냉매선정 및 특성에 대한 고찰)

  • Cho, Yong-Sung;Park, Jae-Hong;Yeom, Gyu-Hak
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.1336-1343
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    • 2007
  • The HVAC takes the most important role in the Electric Multiple Unit for maintaining the healthy and comfortable indoor environment, however we also should consider the outdoor environment in terms of "environment's friendly" because the refrigerant used for the HVAC system is strongly related with the issues of "the Protection of environment" such as "the Global Warming" and "The Ozone layer Depletion". Therefore we survey (1)the potentially harmful impact on human health and the environment through modification of the ozone layer and the Green house effect, and (2)the international and the domestic environment's policies and (3)the potential alternative refrigerants usable for the EMU HVAC in terms of "the environment friendly properties", "the performance" and (4) "the applicabilities of the refrigerant for the EMU HVAC".

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Halon 규제에 대한 대응 방안

  • Kim, Yeong-Bae
    • Fire Protection Technology
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    • s.10
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    • pp.13-18
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    • 1991
  • It seems that the use of one of the major fire-fighting agents-halon-is going to be denied to the fire protection community at the end of the century. It is now being widely accepted that the CFC and halons released into the atomosphere are contributing to both the depletion of the ozone layer green house effect. Therefore, we should research to determine suitable alternative(gaseous) fire extinguishings agents to the halons and improve or develop other extinguishing systems.

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Evaporating heat transfer characteristics of natural gas refrigerants (천연 가스 냉매의 증발 열전달 특성)

  • 김종수
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.28 no.5
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    • pp.359-367
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    • 1999
  • 최근 10년 동안 우리들은 성층권의 오존층 고갈(depletion of ozone layer), 지구온난화(global warming) 및 산성비(acid rain) 등을 포함하는 지구환경문제를 해결하여야 하는 많은 도전을 받고 있다. 몬트리올조약과 Montreal Protocol)이 수정되어 특정 CFC계 냉매들의 생산삭감계획이 앞당겨짐에 따라 우리들은 조속히 이들 문제를 해결해야될 심각한 국면에 직면하고 있다.

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Life Cycle Assessment(LCA) of Rubber Recycling Process in Waste Tire (폐타이어 고무 재활용 공정의 전과정평가 연구)

  • Ahn, Joong Woo;Kim, Jin Kuk
    • Resources Recycling
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    • v.27 no.1
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    • pp.74-83
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    • 2018
  • This study conducted the Life Cycle Assessment(LCA) on waste rubber recycling technology for recovering rubber product from the waste tires. Environmental impacts were assessed for the five categories of impacts: global warming, resource depletion, acidification, eutrophication, photochemical oxide production, and ozone layer depletion. When recycling 1ton of waste tire containing rubber, global warming impact was 1.77E+02 kg $CO_2-eq.$, resource depletion impact was 1.23E+00 kg Sb-eq., acidification impact was 5.92E-01 kg $SO_2-eq.$, eutrophication impact was 1.23E-01 kg $PO{_4}^{3-}-eq.$, photochemical oxide production impact was 3.42E-01 kg $C_2H_4-eq.$, and ozone layer depletion impact was 1.87E-04 kg CFC11-eq. In terms of overall environmental impacts, carbon, softener and electricity the greatest impact, so it is necessary to compare the environmental impacts of the raw materials to replace carbon and softener, and a method to reduce the filler usage in the process is needed. In addition, it is necessary to improve energy efficiency, change to low-energy sources, and apply renewable energy.