• 한국철도학회논문집
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• 제14권1호
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• pp.1-5
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• 2011

지하철 객실은 고농도의 이산화탄소로 오염되기 쉬운데, 이로 인하여 지하철 승객의 졸림, 두통, 무력감 등을 야기하기 쉽다. 이 때문에 환경부에서는 2007년에서는 열차와 지하철 객실의 이산화탄소 농도에 대한 가이드라인을 정한 바 있다. 본 연구에서는 지하철 객차용 이산화탄소 저감 시스템을 개발하고 실험용 객차를 이용하여 성능시험을 수행하였다. 다양한 종류의 개질 제올라이트를 이산화탄소 흡착제로 사용하여 지하철 객실 내부의 이산화탄소 농도를 저감할 수 있었다.

• 한국환경과학회지
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• 제31권11호
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• pp.951-958
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• 2022

The aim of this study was to determine the optimum level of carbon dioxide to maximize the quality and yields of strawberries cultivated in a greenhouse. Specifically, two strawberry cultivars, namely, 'Seolhyang' and 'Maehyang', were subjected to varying concentrations of carbon dioxide and patterns linked to their productivity were noted. Both cultivars showed improvements across various physical variables (i.e., leaf area, crown diameter, plant height, fresh weight, and dry weight) when carbon dioxide concentrations were at 1,500 ppm. The optimum carbon dioxide concentration for increased fruit yields and quality was 1,000 ppm. When carbon dioxide was at 1,000 ppm the yields of 'Seolhyang' and 'Maehyang' increased by 1.99 and 1.78 times, respectively, compared to control plants. The influence of carbon dioxide on fruit color was negligible. However, the carbon dioxide increased the sugar content and sugar-acid ratio of the experimental fruits compared to control plants. Specifically, the sugar-acid ratio, which is directly related to taste, was at its highest when the concentration of carbon dioxide was at 1,000 ppm (i.e., for both 'Seolhyang' and 'Maehyang'). Overall, the application of carbon dioxide culminated in improved yields and fruit quality for both cultivars of interest.

• 한국대기환경학회지
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• 제16권4호
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• pp.389-398
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• 2000

Photocatalytic removal of benzene from air was examined using titanium dioxide photocatalyst films prepared on soda lime glass(50$\times$50$\times$2 mm) by spin coating and chemical vapor deposition. For the measurement of photocatalytic reactivity titanium dioxide coated glass was placed into a batch reactor and concentration of benzene in the reactor was set to abuot 100 ppm, and then illuminated with UV. It was found that catalytic reactivity of titanium dioxide films increased with the increase of titanium dioxide film thickness and then level off beyond a certain film thickness. UV absorption by the films showed the similar trend. The formation of stoichiometric amount of carbon dioxide was confirmed by measurement of carbon dioxide concentration in the reactor. In general spin coated films revealed better photocatalytic reactivity than chemically deposited one within the experimental ranges covered in this study. Morphology and crystal structure of prepared films were investigated by XRD and SEM and they showed significant difference between spin coated films and CVD films. Highest quantum efficiency of prepared titanium dioxide photocatalyst was close to 50%.

• Journal of Construction Engineering and Project Management
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• 제1권1호
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• pp.11-17
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• 2011

According to the United Nations Framework Convention on Climate Change (UNFCCC), many countries around the world have been concerned with reducing Greenhouse Gas (GHG) emissions. Reducing the level of building energy consumption is particularly important in bringing GHG down. Because of this, many countries including the US and the EU are enforcing energy-related policies. However, these policies are focused on management of single types of buildings such as public buildings and office buildings, instead of management on a national level. Thus, although various policies have been enforced in many countries, $CO_2$ management on a national level is still not an area of focus. Therefore, this study proposed a community-based $CO_2$ management process that allows government-led GHG management. The minimum unit of the community in this study is a plot, and the process consists of three steps. First, the current condition of the GHG emission was identified by plot. Second, based on the identified results, the GHG emission reduction target was distributed per plot by reflecting the weighted value according to (i) the target $CO_2$ reduction in the buildings in the standard year, (ii) region, and (iii) building usage and size. Finally, to achieve the allocated target reduction, building energy management was executed according to the properties of the building located on each plot. It can be expected that the proposed community-based $CO_2$ management process will enable government-level GHG management, through which environment-friendly building construction can be promoted.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.262-268
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• 2011

According to the United Nations Framework Convention on Climate Change (UNFCCC), many countries around the world have been concerned with reducing Greenhouse Gas (GHG) emissions. Reducing the level of building energy consumption is particularly important in bringing GHG down. Because of this, many countries including the US and the EU are enforcing energy-related policies. However, these policies are focused on management of single types of buildings such as public buildings and office buildings, instead of management on a national level. Thus, although various policies have been enforced in many countries, CO₂ management on a national level is still not an area of focus. Therefore, this study proposed a community-based CO₂ management process that allows government-led GHG management. The minimum unit of the community in this study is a plot, and the process consists of three steps. First, the current condition of the GHG emission was identified by plot. Second, based on the identified results, the GHG emission reduction target was distributed per plot by reflecting the weighted value according to (i) the target CO₂ reduction in the buildings in the standard year, (ii) region, and (iii) building usage and size. Finally, to achieve the allocated target reduction, building energy management was executed according to the properties of the building located on each plot. It can be expected that the proposed community-based CO₂ management process will enable government-level GHG management, through which environment-friendly building construction can be promoted.

• 한국안전학회지
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• 제11권3호
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• pp.119-125
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• 1996

The experimental work is performed to obtain content levels and characteristics of flue gas in infrared mobile heaters for butane gas with varying the chamber size and its room temperature. The results showed that the oxygen depletion sensor device is operated at 18.3% of oxygen content. And the relation of oxygen content and carbon dioxide content in an enclosed space show linear aspect, but the content rate of carbon monoxide occurs at random without the level of oxygen content and carbon dioxide content.

• 한국산학기술학회논문지
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• 제18권6호
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• pp.478-485
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• 2017

본 연구는 레드키위 과실의 수확 후 숙성반응에 미치는 이산화탄소와 외부 에틸렌처리 효과를 구명하기 위하여 수행되었다. 저장온도 $10^{\circ}C$에 75일 저장 기간 중 레드키위의 숙성과정에 영향을 미치는 이산화탄소와 에틸렌 처리 효과를 구명하기 위하여 과실의 생체 중, 경도, 가용성 당 함량, 유기산 및 시장성 품질 등 물리 화학적 특성을 분석하였다. 레드키위의 생체중은 이산화탄소 처리로 저장 75일후 까지 무 처리와 에틸렌 처리에 비하여 가장 적게 감소된 반면 에틸렌 처리된 과실은 가장 빠르게 감소되었다. 에틸렌 처리과실의 경도는 $10^{\circ}C$ 저온저장 27일 후 4.2kg에서 1.2kg으로 감소된 반면, 이산화탄소 처리된 레드키위 과실은 저장 54일 후까지 1.8kg을 유지하였다. 가용성 당 함량(%)은 에틸렌처리로 $10^{\circ}C$ 저장 27일 후 가장 높은 값을 보인 반면 이산화탄소 처리된 과실에서는 64일 저장 후 가장 높게 나타났다. 레드 키위 과실의 유기산함량은 이산화탄소 처리에서 대조 구와 에틸렌 처리된 과실에 비하여 $10^{\circ}C$에 41일 저장 동안 통계적으로 유의성 있는 높은 값을 유지하였다. 당산 비는 75일 저장 기간 동안 대조 구와 에틸렌 처리된 과일에 비하여 이산화탄소 처리된 키위 과실이 가장 낮은 값을 보였다. 본 연구에서 이산화탄소 처리가 수확 후 레드 키위 과실의 숙성지연과 시장성 품질유지에 매우 효과적으로 나타나 향후 키위 산업에 상업적인 목적으로 이용 가능할 것으로 밝혀졌다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.1153-1158
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• 2005

The passenger cabin of train is generally insulated from exterior environment to ensure the safety of passengers and to enhance the heating and cooling efficiency. Therefore, the IAQ management of passenger cabin is very important in aspect of amenity and health of passengers. In this study, we measured some IAQ factors influencing on the indoor air quality of passenger cabin. The measurement was carried out to investigate the PM-10, PM-2.5, PM-1.0, temperature, relative humidity, carbon monoxide, carbon dioxide leves of KTX. The results showed that the air quality of the cabin was largely satisfactory, but carbon dioxide level was relatively higher. The control of carbon dioxide levels need the extensive research in the future.

• 센서학회지
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• 제26권3호
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• pp.179-185
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• 2017

This article describes the characteristics of nondispersive infrared carbon dioxide gas sensor according to the temperatures and humidifies. In this researches, a thermopile sensor that included application-specific integrated circuit (ASIC) was used and the White-cell structure was implemented as an optical waveguide. The developed sensor modules were installed in gas chamber and then the temperature of gas chamber has been increased from 283 K to 313 K with 10K temperature step. In order to analyze the effects of humidity levels, the relative humidity levels were changed from 30 to 80%R.H. with small humidifier. Then, the characteristics of sensor modules were acquired with the increment of carbon dioxide concentrations from 0 to 2,000 ppm. When the initial voltages of sensors were compared before and after humidifying the chamber at constant temperature, the decrements of the output voltages of sensors are like these: 9mV (reference infrared sensor), 41 mV (carbon dioxide sensor), 2 mV (temperature sensor). With the increment of ambient temperature, the averaged output voltage of carbon dioxide sensor was increased 19 mV, however, when the humidity level was increased, it was decreased 14mV. Based upon the experimental results, the humidity effect could be alleviated by the increment of temperature, so the effects of humidity and temperature could be only compensated by the ambient temperature itself. The estimated carbon dioxide concentrations showed 10% large errors below 200 ppm, however, the errors of the estimations of carbon dioxide concentrations were less than ${\pm}5%$ from 400 to 2,000 ppm.

• 한국항해항만학회지
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• 제43권2호
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• pp.79-85
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• 2019

Climate change is a very vital issue that can be no longer avoided. Korea has been a top-level country Iin dealing with carbon dioxide emissions since 1960. Many studies have been conducted to suppress or eliminate carbon dioxide emissions, which account for a large portion of greenhouse gases. Carbon Capture and Storage (CCS), the most practical method of them, plays a significant role. However, these methods have the disadvantage of the limits of geographical distribution and high possibility of re-emission into the atmosphere. Recently, ocean storage has been studied using Accelerated Weathering of Limestone (AWL), a technique for storing carbon dioxide in the ocean as an alternative to CCS, an underground storage. AWL is a method of converting carbon dioxide into concentrated water in the form of bicarbonate ion and discharging it to the ocean to dilute and store it. It does not cause re-emission to the atmosphere, and the discharged concentrated water increases the alkalinity of the ocean to prevent marine acidification. The objective of this study was to understand the behavior of DIC (Dissolved Inorganic Carbon) including carbon dioxide during the ocean discharge of bicarbonate ion concentrated water in AWL method. This study area was set near Ulleung-do where sufficient water depth and operational efficiency were secured. CORMIX model was used to calculate the material diffusion by submerged discharge using ship.