• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 춘계학술발표대회 논문집
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• pp.172-175
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• 2005

The numerical simulation is performed for the acoustic emission and the wave propagation due to fiber breakage in single fiber composite plates by the finite element transient analysis. The acoustic emission and the following wave motions from a fiber breakage under a static loading is simulated to investigate the applicability of the explicit finite element method and the equivalent volume force model as a simulation tool of wave propagation and a modeling technique of an acoustic emission. For such a simple case of the damage event under static loading, various parameters affecting the wave motion are investigated for reliable simulations of the impact damage event. The high velocity and the small wave length of the acoustic emission require a refined analysis with dense distribution of the finite element and a small time step. In order to fulfill the requirement for capturing the exact wave propagation and to cover the 3-D simulation, we utilize the parallel FE transient analysis code and the parallel computing technology.

• 전기학회논문지
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• 제60권6호
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• pp.1091-1096
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• 2011

Currently, the concern about the environment is the issue all over the world, and in particular, carbon emissions of the power plants will not be able to disregard from the respect of generation cost. This paper proposes DR (demand response) as a method of reducing carbon emissions and therefore, carbon emissions cost. There are a number of studies considering DR, and in this paper, the effect of DR is focused on the side of carbon emission reduction effect considering Time-Of-Use (TOU) program, which is one of the most important economic methods in DSM. Demand-price elasticity matrix is used in this paper to model and analyze DR effect. Carbon emissions is calculated by using the carbon emission coefficient provided by IPCC (Intergovernmental Panel on Climate Change), and generator's input-output characteristic coefficients are also used to estimate carbon emission cost as well as the amount of carbon emissions. Case study is conducted on the RBTS IEEE with six buses. For the TOU program, it is assumed that parameters of time period partition consist of three time periods (peak, flat, off-peak time period).

• 부모자녀건강학회지
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• 제16권1호
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• pp.27-36
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• 2013

Purpose: The purpose of this study was to develop a nocturnal emission and menstruation education program using CAI for Korean elementary school children. Methods: The research design was methodological study a ISD model 4 fields into sub contents in each field of the nocturnal emission and menstruation by CD titles. And to verify the effect of the education program, performance evaluation of the educational program for structured questionnaire was conducted on 120 late school-age children on June, 2010. Results: The results of this study were as follows; Through this, developed program was proved its effectiveness in enhancing knowledge level on nocturnal emission and menstruation in late school-age children(t=14.03, p<.001, t=11.52, p<.001). Conclusion : Accordingly, this program is expected to be an educational program to be used in various educational institutes, communities, and home as well as self-study that allows children themselves to study repeatedly, choosing the contents they want, whenever they hope as an educational program on nocturnal emission and menstruation in school-age children. In addition, it is suggested that various fields of programs should develop in consideration of early sexual maturity.

• 설비공학논문집
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• 제17권12호
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• pp.1123-1131
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• 2005

The floor material is known as the most influential emission source of the residential building, because most floor material is made of wood compound and adhesive like a plywood flooring. Moreover, floor heating system keeps the inside temperature of the material high. As the emission of hazardous chemical compound from the construction material is influenced by many factors, it is necessary to analyze the emission characteristics of the floor material to improve IAQ. In this study, numerical analysis is performed to investigate the emission characteristics of the floor material affected by several factors such as temperature, air exchange rate, initial concentration, and internal diffusion coefficient. A simulation program is also written based on the mass transfer theory. The simulation results show that there is some level of difference on the TVOC concentration when each of the factors is variable.

• The Journal of Asian Finance, Economics and Business
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• 제9권10호
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• pp.15-27
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• 2022

Recently, as carbon dioxide (CO₂) emissions have increased overall and contributed to air pollution, and awareness of environmental degradation has grown. This study examines the impacts and causalities of economic globalization, economic growth, energy consumption, and capital formation on CO₂ emissions in China over the period 1971-2014. The vector error correction model (VECM) and Granger causality test on time-series data are employed to observe the interactions between CO₂ emission, economic globalization, and various economic factors, including economic growth, energy consumption, and capital formation, since China's early stage of globalization. The empirical results indicate the existence of bidirectional causalities from economic growth, gross capital formation, economic globalization, and CO₂ emission to energy consumption, and bidirectional casualty from energy consumption to CO₂ emission relationships in the short run. The findings of this study suggest that indirect bidirectional causalities from economic growth, economic globalization, and capital formation to CO₂ emission through energy consumption are observed. Moreover, economic globalization accelerates CO₂ emission in the short run but decreases it in the long run. To reduce CO₂ emissions, and to ensure sustainable economic growth and economic globalization progress, some crucial energy-saving and energy-efficiency policies, regulatory rules, and laws are recommended.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.365-370
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• 2000

This study represents effect to attain to the exhaust gas and the exhaust noise by the inner shapes of automobile muffler, and obtained optimization-data for the inner muffler shapes by the temperature variation of the exhaust gas in muffler. The results of noise show to decrease in order of model-1, 2 and 3 under that the engine speed is 3500 R.P.M and similar values beyond it. CO represented good the model-2 at low engine speed and model-1 at high engine speed. The model-3 was show to tiny variation difference by the variables. HC decrease mostly by increase of the engine speed and expressed low values the model-2 at 3,000 R.P.M and the model-1 at high speed. Wholly, the model-2 expressed stable results. The temperature distributions expressed high distributions by increase of the engine speed, and the model-3 was express most good among three models.

• 환경영향평가
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• 제14권6호
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• pp.427-441
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• 2005

In order to choose proper dispersion model and emission factors suitable in Korea in evaluating the effect of pollutants emitted by the vehicles in highway on nearby area, various road dispersion models and vehicle emission factors were reviewed. With theoretical inter-comparisons of the exiting models for line source, CALINE 3 and CALINE 4 models which were suggested by US EPA were selected as the road dispersion models for further evaluation with the measurement. The emission factors suggested by Korean Ministry of Environment was turned out to be appropriate since the classification of vehicle kinds was simple and easy to apply in Korea. The comparisons of predicted concentrations by CALINE 3 and 4 models with the measurements in flat, fill and bridge road types showed that CO and PM-10 were in good agreements with experiments and the differences between CALINE 3 and 4 models are negligible. The model concentrations of $NO_2$ by CALINE 4 were also in good agreement with the measurement but those by CALINE 3 were over-predicted. The discrepancies in CALINE 3 model were due to rapid decay reaction of $NO_2$ near the highway, which was not included in CALINE 3 model. For the road type with one & two side cutting grounds, the similar patterns as the flat & fill road type for CO, PM10, & $NO_2$ were observed but the number of data for comparison in these cases were not enough to draw the conclusion. These results lead to the conclusion that CALINE4 model is proper in road environmental impact assessment near the highway in flat, fill and bridge road types.

• 한국ITS학회 논문지
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• 제14권6호
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• pp.14-20
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• 2015

국토교통부는 2020년까지 수송부문 온실가스 배출량의 감축목표를 34.3%로 설정하였다. 목표달성을 위해 에코드라이빙 교육 및 정보를 제공하고 있으나 배출량 감축효과가 미비하다. 따라서 본 연구는 연료 효율적인 최적주행전략 모형의 개발을 목적으로 하였다. 종단경사도 및 길이가 다양한 도로지형을 생성하고 주행모드를 바탕으로 하는 시나리오별 속도 프로파일을 Comprehensive Modal Emission Model에 적용하여 연료소모량을 산정하였다. 연료소모량이 최소가 되는 시나리오와 속도변화량을 도출하였다. 도출된 시나리오와 속도변화량을 기반으로 최적주행전략 모형을 개발하였다. 개발된 모형을 검증하고자 실차테스트를 수행하여 일반 운전자의 속도 데이터를 수집하였다. 개발된 모형에 의해 생성된 속도 프로파일과 일반운전에 생성된 속도 프로파일을 분석하고 각각 연료소모량을 산정하였다. 최적주행 시 소모된 연료소모량이 일반운전보다 평균 11.8% 감축하는 것으로 분석되었다.

• 한국환경과학회지
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• 제20권12호
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• pp.1647-1661
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• 2011

The Government had devised legislation of Special Act and drew up guidelines for improving air quality in Seoul Metropolitan area. In 2007 local government of Seoul, Incheon and Gyeonggi conducted the results of application policy by reduced air pollutants emission for the first time. Although there was reduction of air pollutant emission in each local government, it was ineffective as expected using air pollution monitoring database. Therefore we worked out a way to prepare modeling input data using the results of enforcement plan. And we simulated surface $NO_2$ and PM10 before and after decrease in air pollutants emission and examine reduction effects of air pollution according to enforcement regulation except other influence, by using MM5-SMOKE-CMAQ system. Each local government calculated the amount of emission reduction under application policy, and we developed to prepare input data so as to apply to SMOKE system using emission reduction of enforcement plan. Distribution factor of emission reduction were classified into detailed source and fuel codes using code mapping method in order to allocate the decreased emission. The code mapping method also included a way to allocate spatial distribution by CAPSS distribution. According to predicted result using the reduction of NOx emission, $NO_2$ concentration was decreased from 19.1 ppb to 18.0 ppb in Seoul. In Gyeonggi and Incheon $NO^2$ concentrations were down to 0.65 ppb and 0.68 ppb after application of enforcement plan. PM10 concentration was reduced from 18.2 ${\mu}g/m^3$ to 17.5 ${\mu}g/m^3$ in Seoul. In Gyeonggi PM10 concentration was down to 0.51 ${\mu}g/m^3$ and in Incheon PM10 concentration was decreased about 0.47 ${\mu}g/m^3$ which was the lower concentration than any other cities.

• 대한교통학회지
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• 제27권6호
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• pp.139-146
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• 2009

대기오염 물질배출량 중 도로이동오염원에 의한 배출량은 다른 오염원에 비해 월등히 높은 편이나 관련연구가 미흡한 실정이다. 본 연구에서는 교통량, 속도 및 기타기상 조건의 실시간 자료와 도로기하구조와 같은 도로특성인자를 반영하여, 대기오염 물질 배출에 도로환경요인이 미치는 영향을 분석하였다. 서울시의 실시간 대기오염 데이터와 교통량, 도로관련 데이터를 수집하여 대기오염 물질별 오염배출량 예측 회귀모형식을 구축하였다. 본 연구에서 얻어진 결과를 요약하면 다음과 같다. 첫째, 교통량이 증가할수록 오염물질의 측정량은 증가하며, 속도가 증가할수록 측정량은 감소한다. 둘째, 풍속, 온도, 습도가 증가할수록 측정량은 감소한다. 셋째, 교차로 형태가 복잡할수록 측정량은 감소한다. 예측모형을 검증하기 위하여 예측치와 실측치 데이터를 비교 분석한 결과 총 7곳의 도로변대기오염 측정망 중 실측치와 예측치가 가장 부합하는 측정망은 청계 4가 측정망인 것으로 나타났다. 본 연구는 실시간 대기오염배출량 데이터와 교통량 데이터, 도로환경 특성데이터를 이용하여 예측모형을 구축하여 현실적인 도로환경요인이 대기질에 미치는 영향을 설명하였다는 데 의의가 있다.