• 한국전자파학회지:전자파기술
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• 제2권4호
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• pp.3-9
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• 1991

This paper presents the characteristics of antenna factors of half-wave resonance dipole antennas above a ground plane. The current distributions on a horizontal and vertical dipole antennas were analyzed by the Galerkin's method of moments, and these solutions are used for calculating the horizontal and vertical antenna factors above the ground plane. It is shown that accurate antenna factors of the horizontal and vertical dipole above the ground plane are required of the radiated emission test.

• Journal of Biosystems Engineering
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• 제35권3호
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• pp.151-157
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• 2010

The objective of this study was to analyze the factors affecting on fuel consumption of agricultural tractor. According to the statistical analysis, fuel consumption of agricultural tractor was considerably influenced by kind of operation, throttle engine speed and gear steps of tractor but much less by kind of soil. Specific fuel consumption of the tractor in plowing, dry paddy tilling, wet paddy tilling and wet paddy levelling was 0.33~0.36, 0.30~0.45, 0.19~0.34, 0.28~0.39 L/$kW{\cdot}h$, respectively, and $CO_2$ emission was 0.36~0.45, 0.35~0.58, 0.22~0.42, 0.24~0.37 kg/$kW{\cdot}h$, respectively. Specific fuel consumption and $CO_2$ emission increased as throttle engine speed increased but reversely proportional with gear step of tractor, by which one can reduce fuel consumption and $CO_2$ emission with practicing of "Gear up & Throttle Down" technique in paddy operations.

• 한국환경보건학회지
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• 제32권5호
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• pp.398-403
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• 2006

Indoor air quality can be affected by indoor sources, ventilation, decay and outdoor levels. Understanding the effectiveness of indoor air quality control depends on knowledge of the characteristics of air pollutants in indoor air, especially their quantities and persistence, and the relevance of indoor sources to these factors. Toluene within new and established houses has been determined and factors significant to its presence have been identified. A total of 30 selected houses in Seoul, Asan and Daegu areas that were constructed within 4 years and over 4 years of construction were measured the concentration of toluene from July to September in 2004. Toluene emission decay of double-exponential model exhibited good fit of $Y=276.37e^{-1.21x}(R^{2}=0.34,\;P=0.06)$ for 2 years and then $Y=51.54e^{-0.11x}(R^{2}=0.40,\;P=0.0)$ from 23 years in new houses. In case of living in new houses, noncarcinogenic health effects of exposure to toluene was 1.38 of hazard quotient (HQ) comparing to toluene reference dose of 0.13 mg/kg-day.

• Journal of Microbiology and Biotechnology
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• 제31권1호
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• pp.104-114
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• 2021

Petroleum-contaminated soil is considered among the most important potential anthropogenic atmospheric methane sources. Additionally, various rhizoremediation factors can affect methane emissions by altering soil ecosystem carbon cycles. Nonetheless, greenhouse gas emissions from soil have not been given due importance as a potentially relevant parameter in rhizoremediation techniques. Therefore, in this study we sought to investigate the effects of different plant and soil amendments on both remediation efficiencies and methane emission characteristics in diesel-contaminated soil. An indoor pot experiment consisting of three plant treatments (control, maize, tall fescue) and two soil amendments (chemical nutrient, compost) was performed for 95 days. Total petroleum hydrocarbon (TPH) removal efficiency, dehydrogenase activity, and alkB (i.e., an alkane compound-degrading enzyme) gene abundance were the highest in the tall fescue and maize soil system amended with compost. Compost addition enhanced both the overall remediation efficiencies, as well as pmoA (i.e., a methane-oxidizing enzyme) gene abundance in soils. Moreover, the potential methane emission of diesel-contaminated soil was relatively low when maize was introduced to the soil system. After microbial community analysis, various TPH-degrading microorganisms (Nocardioides, Marinobacter, Immitisolibacter, Acinetobacter, Kocuria, Mycobacterium, Pseudomonas, Alcanivorax) and methane-oxidizing microorganisms (Methylocapsa, Methylosarcina) were observed in the rhizosphere soil. The effects of major rhizoremediation factors on soil remediation efficiency and greenhouse gas emissions discussed herein are expected to contribute to the development of sustainable biological remediation technologies in response to global climate change.

• 4차산업연구
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• 제3권2호
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• pp.1-10
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• 2023

Purpose - The main purpose of the paper is to examine the variables affecting carbon emissions in different nations around the world. Research design, data, and methodology - To measure its impact on carbon emissions, secondary data has data of the top 50 Countries have been taken. The stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT) model have been used to quantify the factors that affect carbon emissions. A modified version using Industry 4.0 and region in fundamental STIRPAT model has been applied with the ordinary least square approach. The outcome has been measured using both the basic and extended STIRPAT models. Result - Technology found a positive determinant as well as statistically significant at the alpha level of 0.001models indicating that technological innovation helps reduce carbon emissions. In total, 4 models have been derived to test the best fit and find the highest explaining capacity of variance. Model 3 is found best fit in explanatory power with the highest adjusted R2 (97.95%). Conclusion - It can be concluded that the selected explanatory variables population and Industry 4.0 are found important indicators and causal factors for carbon emission and found constant with all four models for total CO2 and Co2 per capita.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.155-156
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• 2023

This study aims to analyze the factors that cause differences in the evaluation results of the life cycle carbon emissions assessment of buildings in both Korea and China as part of the methodology research of building life cycle assessment for Chinese buildings to promote building life cycle assessment in China. Specifically, it examines the building LCA standards of Korea and the standard for building carbon emission calculation in China as mentioned in the green building certification systems of both countries. Based on the investigation of the two standards, the life cycle carbon emissions of the evaluation target building were evaluated using the building life cycle assessment methods of both countries, and the influencing factors that cause differences in the life cycle carbon emission assessment results of the two countries were analyzed.

• 에너지공학
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• 제23권3호
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• pp.72-81
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• 2014

기후변화에 관한 정부 간 패널기구(IPCC)는 온실가스 배출통계 작성과 관련한 국제적 기준을 정한 보고서에 따라 온실가스 배출통계의 정밀도 및 난이도를 고려하여 Tier 1/2/3의 세 가지의 방법론을 제시하였다. 국내의 경우 기존의 인벤토리 구축은 우리나라 전체 에너지소비량을 교통수단별 배출계수를 적용하여 산출하는 Top-down 방식으로 이루어 졌었고, 배출계수는 승용차의 계속적인 증가와 도로 구간 변화가 반영되지 못한 국내 교통상황에서 진행되었다. 온실가스 배출량 산정에 있어 $CO_2$의 배출량은 연료에 따른 탄소 함량으로 산정 하는 것이 보다 정확한 배출량 산정을 할 수 있다고 IPCC에서 제시함에 따라 정확한 배출량 산정을 위해 수송용 연료에 대하여 국가 고유 탄소 함량을 월별 또는 계절별 분석을 통하여, 국가 온실가스 통계의 정확도 제고와 최신 배출통계를 통해 앞선 기후변화 대응 대책 수립을 가능하게 할 것이다.

• 한국대기환경학회지
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• 제22권4호
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• pp.451-458
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• 2006

Automotive exhaust is suspected to be one of the major reasons of the rapid increase in greenhouse effect gases in ambient air. As the concerns regarding global worming were increased, the pressure on mobile source greenhouse gas (GHG) emission were also increased. Carbon Dioxides contribute over 90% of total GHG emission and the mobile source occupies about 20% of this $CO_2$ emission. In this study, in order to investigate $CO_2$ emission characteristics from gasoline and LPG passenger cars (PC), which is the most dominant vehicle type in Korea, 53 vehicles were tested on the chassis dynamometer. $CO_2$ emissions and fuel consumption efficiency were measured. The emission characteristics by fuel type, model year, mileage, vehicle speed and transmission type were also discussed. Test modes used in this study were NIER 10 modes and CVS-75 mode, which have been used for developing emission factors and testing new vehicles respectively. The results of this study showed that the main factors which have significant influences on the $CO_2$ emissions are fuel type, transmission type, displacement of vehicle and mileage. The correlation between $CO_2$ emission and FE was also determined by comparing $CO_2$ emission and fuel consumption efficiency. The overall results of this study will greatly contribute to domestic greenhouse gas emissions calculation and designing national strategies for climate change.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2009년도 정기총회 및 추계학술대회 논문집
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• pp.117-119
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• 2009

This paper presents a simulation model based on support vector regression (SVR) for flicker emission estimation from wind turbines. Training patterns are developed by varying the wind speed and network parameters that might affect the expected flicker levels. A comparison is done to the fixed speed wind turbine (WT), which leads to a conclusion that the factors mentioned above have different influences on flicker emission. The simulation results have shown that the flicker estimation is performed accurately.

• 비파괴검사학회지
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• 제7권1호
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• pp.7-17
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• 1987

Leak detection testing for the pipeline system was performed by the acoustic emission method. It was found that the detected signal spectrum was influenced by the frequency response of sensors and pressure changes. AE parameters and frequency spectrum distributions were used to analyze the leak signals. The slope rise time of AE parameters were the important factors for distinguishing leak signals. The amplitude of leak signal was more affected by the changes of leak, rate and pressure than those of leak type.