• 한국태양에너지학회:학술대회논문집
• /
• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
• /
• pp.259-264
• /
• 2009

Most of the fossil power plants firing lower grade coals are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. The poor combustion conditions are directly related to the gas flow deviation in upper furnace and convection tube-bank but a less reported issue related to in large-scale oppose wall fired boilers. In order to develop a on-line combustion monitoring system and suggest an alternative heat flux estimation method at tube bank, which is very useful information for boiler design tool and blower optimizing system, field test was conducted at operating power boiler. During the field test the exhaust gases' temperature and tube metal temperature were monitored by using a spatially distributed sensors grid which located in the boiler's high temperature vestibule region. At these locations. the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. Test results showed that the flue gas monitoring method is more proper than metal temperature distribution monitoring for real time combustion monitoring because tube metal temp. distribution monitoring method is related to so many variables such as flue gas, internal flow unbalance, spray etc., Heat flux estimation at the tube bank with flue gas temp. and metal temp. data can be alternative method when tube drilling type sensor can't able to use.

• 한국항해항만학회지
• /
• 제35권5호
• /
• pp.387-392
• /
• 2011

태양광발전은 독립전원으로써의 가치는 미미하나 도시전체의 탄소발생량 저감 및 화석연료 사용 저감을 위한 분산전원으로써 가치가 매우 높은 전력원이다. 하지만 태양광발전의 경우 기상조건에 따른 발전량 변동이 심하기에 분산전원으로써 효율적으로 사용하기 위해서는 큰 변동폭을 효과적으로 제어하기 위한 실시간 모니터링이 이루어져야 한다. 하지만 태양광발전량을 좌우하는 일사량은 예측치가 존재하지 않기에 이를 예측해야 하고 본 연구에서는 과거의 일사량을 직산분리 하여 구름의 짙은 정도나 두께 등을 유추할 수 있는 대기투과율을 일기예보에서 발표하는 날씨별로 대푯값을 산정하고 이를 일사량 예측식에 대입하여 일사량을 예측하였다. 그리고 실측 일사량 및 CRM(Cloud Cover Radiation Model)기법인 Kasten and Czeplak의 식을 통해 계산된 예측일사량과의 비교를 통해 검증하였다.

• 전기학회논문지
• /
• 제64권5호
• /
• pp.667-679
• /
• 2015

The bearer of the power sector's ETS compliance cost is power consumer for the following reasons. Firstly, power companies are constrained in establishing appropriate strategies to comply with ETS regulations due to the structural differences between the domestic power market and emission trading system. In other words, because power companies do not have a right to determine price and production of electricity, they have to compete with other companies under disadvantaged conditions in the emission trading market. Secondly, because ETS compliance cost is part of power production costs as it is also clearly written in the national greenhouse gas reduction road-map and the second energy supply plan, the cost should be included in power price following the power market operation rule. Thirdly, the most effective method to reduce carbon emissions in power sector is to reduce power demand, which is efficiently achieved through raising power price to a realistic level. Low power price in Korea is the major cause of rising power demand which is also the major cause of rising GHG emission. Therefore, power sector's ETS compliance cost should be included in power price to encourage power consumers' actions on reducing power consumption. Fourthly, when externality cost occurs in the process of delivering public services, usually beneficiary pay principle is applied to identify the cost bearer. Since electricity is one representative public good, the bearer of power sector's ETS compliance cost is power consumer.

• 한국산학기술학회논문지
• /
• 제18권8호
• /
• pp.338-343
• /
• 2017

본 논문은 이산화탄소 배출저감 및 산업폐기물을 재활용하기 위한 일환으로 산업부산물인 고로슬래그 미분말을 사용하였다. 고로슬래그 미분말은 선철의 제련 시 부산물로서 발생하는 고온 용융상태의 고로슬래그를 물로 급냉 시켜 유리화한 것으로 반응성이 높아 시멘트 및 콘크리트용 혼화재료로 다양하게 사용되고 있다. 고로슬래그 미분말을 치환한 콘크리트는 수화발열속도 저감, 온도상승 억제, 장기강도 향상, 수밀성 증대에 의한 내구성 향상 및 염화물 이온 침투억제에 의한 철근의 발청 억제 등의 다양한 효과를 기대할 수 있다. 그러나, 재령 초기 낮은 압축강도로 인해 사용량이 적은 실정이다. 따라서, 본 연구에서는 고로슬래그 미분말을 치환할 경우 낮은 압축강도를 보완하기 위해 증기양생이 초기 강도 발현에 미치는 영향을 평가하였고, 압축강도, SEM, EDS, XRD와의 관계를 분석하여 콘크리트의 압축강도 발현특성을 검토하였다. 그 결과 고로슬래그 미분말을 30% 치환한 콘크리트가 가장 우수하였으며, 이는 증기양생에 의해 고로슬래그 미분말의 피막을 파괴하여 ettringite 및 C-S-H겔 등의 수화물을 생성함으로 압축강도에 영향을 마친 것으로 판단된다.

• KIEAE Journal
• /
• 제7권5호
• /
• pp.93-98
• /
• 2007

Effort has been performed for latest 20 years to improve resident's comfort and indoor environment in building. And interest and effort to improve indoor air environment among various indoor environment elements have continuously increased since 1990s, because it is examined scientifically that various contaminants generated indoor affect human body. Specially, indoor air contaminants generated from apartments are those exhausted from resident's indoor environment, closing materials and household. Indoor air environment in buildings is different according to pollution degree, existence availability of pollution source, ventilation amount, and meteorology. It is known that other contaminants more than about 900 kinds generate according to a kind of work or action in a room. Specially, nowadays buildings are well insulated and confidentiality-centered for environment protection and economical side. So indoor air contaminants are generated from indoor air pollution sauces of unprepared ventilation, human body carbon dioxide emissions, and various building materials. when these are accumulated in long term human body, it is harmful to resident's health, but awareness for this is very insufficient. Because bedroom is space that people inhabit for a long time by unconscious state and indoor environment occupies important part for resident's health and quality of life at sleep, the actual condition of air quality is investigated, improvement countermeasure is considered, and ventilation amount is analyzed. In this study, putting case that the most longest stayed time is sleeping time when people inhabit in the apartment, the air quality according to volume of bedroom space at sleep was measured and analyzed, and the data acquired will be the basis for improvement on this.

• 농촌계획
• /
• 제20권4호
• /
• pp.145-155
• /
• 2014

Since greenhouse gas emissions increase continuously, the authorities have needed climate change countermeasure for adapting the acceleration of climate change damages. According to "Framework Act on Low Carbon, Green Growth", Korean local governments should have established the implementation plan of climate change adaptation. These guidelines which is the implementation plan of climate change adaptation should be established countermeasure in 7 fields such as Health, Digester/Catastrophe, Agriculture, Forest, Ecosystem, Water Management and Marine/Fisheries. Basically the Korean local governments expose vulnerable financial condition, therefore the authorities might be assessed the vulnerability by local regions and fields, in order to establish an efficient implementation plan of climate change adaptation. Based on this concepts, this research used 3 methods which are LCCGIS, questionnaire survey analysis and analysis of existing data for the multiphasic vulnerable assessment. This study was verified the correlation among 7 elements of climate change vulnerability by 3 analysis methods, in order to respond climate change vulnerability in rural areas, Seocheon-gun. If the regions were evaluated as a vulnerable area by two or more evaluation methods in the results of 3 methods' comparison and evaluation, those areas were selected by vulnerable area. As a result, the vulnerable area of heavy rain and flood was Janghang-eup and Maseo-myeon, the vulnerable area of typhoon was Janghang-eup, Masan-myeon and Seo-myeon. 3 regions (i.e. Janghang-eup, Biin-myeon, Seo-myeon) were vulnerable to coastal flooding, moreover Masan-myeon, Pangyo-myeon and Biin-myeon exposed to vulnerability of landslide. In addition, Pangyo-myeon, Biin-myeon and Masan-myeon was evaluated vulnerable to forest fire, as well as the 3 sites; Masan-myeon, Masan-myeon and Pangyo-myeon was identified vulnerable to ecosystem. Lastly, 3 regions (i.e. Janghang-eup, Masan-myeon and Masan-myeon) showed vulnerable to flood control, additionally Janghang-eup and Seo-myeon was vulnerable to water supply. However, all region was evaluated vulnerable to water quality separately. In a nutshell this paper aims at deriving regions which expose climate change vulnerabilities by multiphasic vulnerable assessment of climate change, and comparing-evaluating the assessments.

• 한국산학기술학회논문지
• /
• 제12권11호
• /
• pp.5321-5329
• /
• 2011

공간배치는 총 에너지 사용량의 20% 이상을 차지하는 교통 부분에서의 탄산가스 배출량을 결정하는 중요한 이슈이다. 교통 부분에서 사용하는 에너지 사용량을 줄이는 방법으로서 고효율의 교통수단 개발과 함께 도시에서의 이동량을 효과적으로 감소시킬수 있는 공간배치의 중요성이 더욱 증가하고 있는 실정이다. 이러한 맥락에서 본 연구에서는 도시계획 초기 단계에서 토지이용계획 및 교통계획을 기반으로 해당 도시에서의 이동 발생량을 추정할 수 있는 방법론을 제안한다. 본 연구에서는 토지이용계획 및 교통계획에서 획득할 수 있는 정보, 즉 단위 기능 용도 지역의 위치, 면적, 연면적, 도로체계와 같은 정보만을 이용하여 이동량을 추정할 수 있는 방법을 제시한다.

• 융복합기술연구소 논문집
• /
• 제2권1호
• /
• pp.24-30
• /
• 2012

In this study, the trucks(2.9-liter) have been developed to use DME as fuel, and performance test of the vehicle's DME engine, power, emissions, fuel economy and vehicle aspects was conducted. For experiments, the fuel system(common-rail injectors and high-pressure pump included) and the engine control logic was developed, and ECU mapping was performed. As a result, the rail pressure from 40MPa to approximately 65% increase compared to the base injector has been confirmed that. Also, the pump discharge flow is 15.5 kg/h when the fuel rail pressure is 400rpm(40 MPa), and the pump discharge flow is 92.1 kg/h when the fuel rail pressure is 2,000rpm(40MPa). The maximum value of full-load torque capability is 25.5kgfm(based on 2,000rpm), and more than 90% compared to the level of the diesel engine were obtained. The DME vehicle was developed in this study, 120 km/h can drive to the stable, and calculated in accordance with the carbon-balance method of fuel consumptions is 5.7 km/L.

• 자원리싸이클링
• /
• 제20권2호
• /
• pp.3-15
• /
• 2011

현재 CDM사업 등록은 대부분 에너지, 화학공정, 제조공정 분야에서 이루어지고 있다. 그러나, 무기질 자원재활용을 통한 CDM사업 등록은 그렇게 많지 않은 실정이다. 본 논문에서는 국내 무기질 폐기물의 재자원화를 통한 CDM사업 등록 가능성을 알아보기 위하여 국내외 CDM사업 현황 분석 및 적용사례를 조사하였다. 조사결과 CDM사업 등록 사례는 대량으로 활용할 수 있는 산업 중의 하나인 시멘트산업의 원료 대체화 분야에서 다수의 등록이 이루어진 것으로 조사되었다. 우리나라에서의 CDM사업 적용 전망은 산업의 규모, 무기질 자원 활용 산업 및 온실가스 배출량을 분석하고 대량으로 활용할 수 있을 정도로 지속적으로 발생되는 우기질 폐가물의 현황 등을 면밀히 검토해야 할 것으로 판단된다.

• Smart Structures and Systems
• /
• 제24권4호
• /
• pp.541-552
• /
• 2019

Construction development and greenhouse gas emissions have globally required a strategic management to take some steps to stain and maintain the environment. Nowadays, recycled aggregates, in particular ceramic waste, have been widely used in concrete structures due to the economic and environmentally friendly solution, requiring the knowledge of recycled concrete. Also, one of the materials used as a substitute for concrete cement is wollastonite mineral to decrease carbon dioxide (CO2) from the cement production process by reducing the concrete consumption in concrete. The purpose of this study is to investigate the effect of wollastonite on the mechanical properties and durability of conventional composite concrete, containing recycled aggregates such as compressive strength, tensile strength (Brazilian test), and durability to acidic environment. On the other hand, in order to determine the strength and durability of the concrete, 5 mixing designs including different wollastonite values and recovered aggregates including constant values have been compared to the water - cement ratio (w/c) constant in all designs. The experimental results have shown that design 5 (containing 40% wollastonite) shows only 6.1% decrease in compressive strength and 4.9% decrease in tensile strength compared to the control plane. Consequently, the use of wollastonite powder to the manufacturing of conventional structural concrete containing recycled ceramic aggregates, in addition to improving some of the properties of concrete are environmentally friendly solutions, providing natural recycling of materials.