• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.162-164
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• 2000

The numerical simulation of air movement in a room using CFD (Computational Fluid Dynamics) requires a complicated set of input data, This includes physical data, such as space geometry, characteristics of supply air flow and contaminant source, etc. as well as computational domain. Among the input data, the boundary conditions related to the inlet are particularly crucial in order to achieve accurate computation results, although there are many other parameters which may also affect the results. (omitted)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.10a
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• pp.241-242
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• 2006

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.97-98
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• 2001

폐기물 소각로는 주입 폐기물의 성상이 균일하지 못하므로 폐기물의 불완전 연소에 의한 유해중간 생성물들이 생성되므로 논란이 되어왔다. 이를 제어하기 위해서는 공기량, 공기 주입방법, 공기 예열온도등에 운전조건들의 선정이 매우 중요하다. 이를 위해 진행되어온 연구는 크게 실험적 방법과 수치 해석적 방법의 두 범주로 나뉘어진다. 이에 본 연구에서는 수치해석적 방법으로 광주 상무신도심에 설치 가동중인 200톤/일 용량의 소각로내의 열유동 현상을 해석하기 위하여 고체 폐기물이 매우 빠르게 탈휘(devolatilization)되는 것으로 가정, 메탄가스로 단순화(Chen et al, 1999)하였다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.309-310
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• 2002

싸이클론은 제작 및 운전이 간단하고 비용이 적게 늘기 때문에 대기오염물질의 샘플링과 여러 산업 공정에서 분진을 제어, 분리하는데 널리 사용되고 있다 하지만 자은 입자에 대한 분리효율이 낮기 때문에 싸이클론의 구조 및 형태를 변화시키거나 싸이클론내에 전기장을 형성시키는 등의 운전조건을 변화시켜 높은 분리효율을 얻으려는 연구가 수행되어 왔다. (Plucinski et al., 1990) 본 연구에서는 싸이클론 입구측의 구조를 변화시켜 싸이클론에 유입되는 기체의 조건을 다르게 하여 분리효율 특성을 알아본다. (중략)

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.1
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• pp.55-62
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• 2003

Leachate generated from landfill material flows through soil gravitationally downward and. continues to flow until it encounters groundwater, posing the thread of pollution. So selection of liner material having a low permeability and testing method are required. The study was performed to find bentonite content of soil-bentonite mixtures for using as liner and cover of waste landfills. This paper includes results of consolidation tests and permeability tests and evaluates suitability and properties of soil-bentonite mixtures as impervious materials.

• 연구논문집
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• s.28
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• pp.137-143
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• 1998

In the case of a boiler, scale is made in the tube by the chemical reactions of Ca and Mg ions contained in the water, and heat transfer rate is reduced because of increasement of heat resistance in the pipe of the heat flow. Thus it brings to reduce the energy efficiency and to make environmental pollution by the use of chemicals for the prevention and removement of scale. In this paper, we discussed the design of electronic generator for dual ultrasonic transmitters and analyzed the effect of scale prevention by ultrasound.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.65-67
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• 2002

대기 중 오염물질의 측정은 크게 채취와 분석의 단계로 구분할 수 있다. 오염물질의 측정과 관련된 정도관리도 당연히 이들 2개의 분야에 대한 각각의 가치를 동일하게 비교하여야 한다. 그러나 아직까지 많은 연구주체들에 의해 시도된 대기관측과 관련된 연구분석의 결과들은 분석의 정도관리에 대해 많은 가치를 부여함에도 불구하고, 채취의 정도관리에 대해서는 나름대로 충분한 검정이 이루어지지 않은 경우를 빈번하게 목격할 수 있다 (Kim and Lindberg, 1994). (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.105-106
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• 2002

대기 중으로 배출된 오염물질의 확산을 예측하기 위해서는 대기의 흐름과 배출원의 특성이 가장 중요한 자료이다. 최근 많이 사용하는 대기확산 모델의 기상자료는 단일 측정기상자료를 입력자료로 이용하고 있지만, 이런 방법은 모델링 영역 전체를 동시간대에서는 같은 풍향과 같은 풍속이라고 가정하여 모델링을 수행하는 것이다. (중략)

• Journal of Korea Water Resources Association
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• v.54 no.7
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• pp.495-507
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• 2021

With the recent industrial development, accidental pollution in riverine environments has frequently occurred. It is thus necessary to simulate pollutant transport and dispersion using water quality models for predicting pollutant residence times. In this study, we conducted a field experiment in a meandering reach of the Sum River, South Korea, to validate the field applicability and prediction accuracy of RAMS+ (River Analysis and Modeling System+), which is a two-dimensional (2D) stream flow/water quality analysis program. As a result of the simulation, the flow analysis model HDM-2Di and the water quality analysis model CTM-2D-TX accurately simulated the 2D flow characteristics, and transport and mixing behaviors of the pollutant tracer, respectively. In particular, CTM-2D-TX adequately reproduced the elongation of the pollutant cloud, caused by the storage effect associated with local low-velocity zones. Furthermore, the transport model effectively simulated the secondary flow-driven lateral mixing at the meander bend via 2D dispersion coefficients. We calculated the residence time for the critical concentration, and it was elucidated that the calculated residence times are spatially heterogeneous, even in the channel-width direction. The findings of this study suggest that the 2D water quality model could be the accidental pollution analysis tool more efficient and accurate than one-dimensional models, which cannot produce the 2D information such as the 2D residence time distribution.

• Resources Recycling
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• v.30 no.3
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• pp.63-69
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• 2021

Supply deficit of lead commodities and environmental pollution can be simultaneously resolved through the recovery and recycling of waste lead. The recent recovery of lead through recycling of the lead battery waste is a positive development. To maximize the effect of lead recovery and recycling in the future, the updated status of the lead material flow should be recognized. However, such an analysis at the preliminary stages may be cumbersome owing to the complexity and diversity of emission sources and material streams. At this stage, a preliminary screening by domestic lead flow using public information should be feasible. Therefore, in this study, using the data from the UN Comtrade and domestic PRTR (Pollutant Release and Transfer Register) databases, the amounts of lead import, emission, and transfer were identified and cross-checked with the domestic lead flow described in the National Material Flow Analysis database. The lead flow for major categories such as waste lead-acid batteries showed a rough consistency between the databases.