• Title/Summary/Keyword: 지표침적

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A Simulation for Dry Depositon Velocity of Air Pollutants over various surfaces. (지표 부근에서의 대기오염물질 건성 침적속도에 관한 모수화)

  • 이화운;박종길
    • Journal of Environmental Science International
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    • v.3 no.4
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    • pp.367-372
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    • 1994
  • A predictive model is demonstrated for gas removal rates from the aklosphere by dw deposition. Typical deposition velocities are complex functions of surface types, atmospheric stabilities, friction velocities, air pollutants, and so on. In this paper we simulated the calculation of dry deposition velocities near the earth surfaces, simultaneously we estimated real dry deposition velocities using the previous simulation. The measurement taken over a deciduous forest by Padro et d.(1988) were used to verify this model. In the comparison of the value of deposition velocity between numerical computation and observation, there are partially overestimations and underestimations between them, but we can speak that they are in a good accordance.

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A Study on the Estimation of the Intensity and Total Mass of Asian Dust Passed through Korea (한반도에 유입된 황사의 강도 및 통과량 추정에 관한 연구)

  • 송상근;김유근;정주희
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.249-250
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    • 2003
  • 최근 동아시아의 발원지에서부터 편서풍을 따라 이동해 오는 황사는 중국의 북동부 공업지대에서 방출되는 중금속 오염물질까지 함께 섞여 수송되므로 그 피해는 훨씬 심각하다. 지난 20년 동안 황사에 대한 많은 연구가 발원지의 기원, 수송 및 침적 메카니즘, 그리고 황사의 광학적 특성과 물리적 특성의 정성분석을 중심으로 이루어져 왔다. 이들 연구는 주로 위성, 라이다. 원격탐사 그리고 기타 지표관측 자료를 이용하여 황사의 광학적 두께 및 화학성분 분석, 일기도를 이용한 기상장 분석, 그리고 중규모 기상 모델과 황사의 장거리 수송에 집중되어 있었다(정관영과 박순웅, 1997; Murayama et al., 2001). (중략)

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Analysis on the contaminant transport in subsurface soil at Daeduk site (대덕부지 토양내 오염물 이동 해석)

  • Suh, Kyung-Suk;Kim, Eun-Han;Hwang, Won-Tae;Jeong, Hyo-Joon;Han, Moon-Hee;Lee, Chang-Woo
    • Journal of Radiation Protection and Research
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    • v.28 no.3
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    • pp.155-163
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    • 2003
  • The groundwater flow and contaminant transport numerical models have been established for analyzing the movements of pollutants in subsurface soil at Daeduk site. The groundwater flow and concentration of U-234 using the numerical models were simulated around Daeduk nuclear facilities. The computed groundwater flow was mainly advected toward the direction of east and southeast around HANARO in the site. The radioactive material entered into the subsurface soil was transported along the same direction with groundwater flow. The radioactive material deposited on the surface from the calculated concentration distributions was not affected by surrounding environment of the site.

Variation of Microfibril Angle Within Stems of Three Commercial Softwoods Grown in Korea (국내산 주요 침엽수 3종의 수간 내 마이크로피브릴 경사각의 변이)

  • Eun, Dong-Jin;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.36 no.4
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    • pp.77-83
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    • 2008
  • Radial and axial variations of microfibril angle (MFA) within stems of three commercial softwoods (Pinus densiflora, Pinus koraiensis and Pinus rigida) grown in Korea were examined by iodine crystal deposition method. The average MFA were $16.4^{\circ}$ in Pinus densiflora, 14.4, in Pinus koraiensis, and $26.2^{\circ}$ in Pinus rigida, respectively. The MFA in earlywood and latewood decreased with age to about 15~20 years, and then remained almost constant. The MFA of latewood was slightly smaller than that of earlywood. The MFA in the three species was a little smaller at the base of stem and decreased slightly with increasing tree height, but no significant difference by height was identified only in earlywood of Pinus rigida. Consequently, it was considered that the MFA could be an useful index for identifying juvenile wood and adult wood of Pinus densiflora, Pinus. koraiensis and Pinus rigida.

A Practical Methodology for Determination of Derived Intervention Levels on Relocation Following a Nuclear Accident (원자력 사고후 주민의 이주를 위한 유도개입준위 산정의 실용적 방법론)

  • Hwang, Won-Tae;Kim, Eun-Han;Suh, Kyung-Suk;Jeong, Hyo-Joon;Han, Moon-Hee;Lee, Chang-Woo
    • Journal of Radiation Protection and Research
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    • v.29 no.2
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    • pp.91-96
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    • 2004
  • A practical methodology for the determination of derived intervention levels (DILs) on relocation following an accidental release of radionuclides was designed based on dose rate on the ground. The influence of DILs was investigated with respect to the change of parameter values, which are dependent on socio-environmental characteristics in distinction from temporary and permanent relocations. The DILs on relocation showed a distinct difference depending on effective removal half-life of radionuclides following a deposition, delay time in measurement and residential characteristics. In particular, the delay time. In measurement was an important factor in determination of DILs in the case of an assumption that dose rate on the ground declines in a power function, not in an exponential function. The DILs showed lower numerical values as longer effective half-life, longer delay time In measurement and longer exposure time.

A Comparative Analysis of Fishery and Marine Environment-related Policies on Estimated Amount of Fishery Debris Caused by Fishing (조업기인 어업쓰레기 발생추정량에 대한 어업 및 해양환경 관련 정책 비교분석)

  • Seong, Eun-hye;Kim, Kyung-shin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.906-917
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    • 2022
  • This study aimed to compare differences according to categories of fishery and marine environmental policies for the (estimated) amount of fishery waste generated by fishing, and to analyze the correlation between associated independent and dependent variables. The independent variables were divided into three dif erent sectors. The first sector included precautionary policies that observed eco-friendly fishing support program, institutional prevention activities, and physical barriers installation. The second sector with the current management policies included the relevant vessel operations, establishment of fishery order, fishery restructuring, and fishery ground clean-up. Thirdly, post-response policies comprised the litter purification from river to shoreline, the collection and removal of marine, sedimentary, and floating debris, purchasing salvaged debris generated while fishing, fishery waste disposal, and repairing damage caused by marine litter. The indicator used was the settlement amount by each program. The dependent variable was the estimated amount of fishery waste and the indicator was the sum of the loss of traps and gill nets and the loss of their appendages. According to the results of Kruskal-Wallis Test, the estimated amount of fishery waste was highest in the East Sea in terms of sea area and the highest in the Si(city) according to basic local municipality. The settlement amount related to the marine environment services was largest in the Gun(county). Further, there were significant differences between Gun(county) and the other regions(Si(city) and Gu(autonomous district)) with respect to most variables. The variables related to the estimated amount of fishery debris were the project purchasing salvaged debris generated while fishing and fishery waste disposal program in the post-response policies.