• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.34 no.4
• /
• pp.1053-1063
• /
• 2014

This study presents a sustainable design method that optimizes the embodied energy of concrete beam based on the concept of sustainable development that effectively utilizes natural resource and energy within the range that our succeeding generation can afford to utilize. In order to get the flexural strength carrying the ultimate load, concrete beam sections are designed by optimization that consists of the embodied energy as a objective function and the requirements of design code as constrained conditions. The sustainable design can be used to minimize the embodied energy consumed in material production, construction, operation, demolition of the infrastructure. As a result of comparison of the cost and the embodied energy optimizations based on practical beam sections, it is shown that 20% embodied energy saving and 35% $CO_2$ emission saving are achieved by sacrificing 10% cost increase. The sustainable design method provides a new effective methodology that manages the strength design concept based on cost minimization together with economic feasibility and sustainability. In addition, the method is expected to be applied to more various structural design practices.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.30 no.3
• /
• pp.265-274
• /
• 2017

This study presents a sustainable design method to optimize the embodied energy and $CO_2$ emission complying with the design code for reinforced concrete column. The sustainable design method effectively achieves the minimization of the environmental load and energy consumption whereas the conventional design method has been mostly focused on the cost saving. Failure of reinforced concrete column exhibits compressive or tensile failure mode against an external force such as flexure and compression; thus, optimization analyses are conducted for both failure modes. For the given sections and reinforcement ratios, the optimized sections are determined by optimizing cost, embodied energy, and $CO_2$ emission and various aspects of the sections are thoroughly investigated. The optimization analysis results show that 25% embodied energy and 55% $CO_2$ emission can be approximately reduced by 10% increase in cost. In particular, the embodied energy and $CO_2$ emission were more effectively reduced in the tensile failure mode rather than in the compressive failure mode. Consequently, it was proved that the sustainable design method effectively implements the concept of sustainable development in the design of reinforced concrete structure by optimizing embodied energy consumption and $CO_2$ emission.

• Korean Journal of Construction Engineering and Management
• /
• v.17 no.3
• /
• pp.52-60
• /
• 2016

This study investigates and analyzes the total amount of energy consumption and $CO_2$ emission during the material manufacturing, transportation, construction, operation, and disposal phases of eight elementary school buildings in South Korea. Toward this ends, the hybrid LCA model is proposed. The life cycle energy consumption and $CO_2$ emission of eight case buildings are assessed using the hybrid LCA model with an assumption that the operation period is 40 years. As a result, the embodied(sum of the energy consumption in the material manufacturing, transportation and construction phases), operational and disposal energy were 2,279, 11,182, $228Mcal/m^2$, respectively, on average. The average embodied, operational, and disposal $CO_2$ emission were 604, 2,708, 60 kg-$CO_2/m^2$, respectively, on average. This result indicates that about 17% of life cycle energy (or $CO_2$ emission) is consumed in the material manufacturing, transportation and construction phases. Thus, it is necessary to consider the embodied energy and $CO_2$ emission to reduce the life cycle energy and $CO_2$ emission of school buildings. In addition, while the insulation standard of building have been provided based on the climate zone, energy consumption in operation phase still varied depending on the regions in this study. Thus, the insulation standard of building needs to be improved through considering the climate of regions in detail.

• 에너지협의회보
• /
• s.19
• /
• pp.10-15
• /
• 1991

• Journal of Energy Engineering
• /
• v.2 no.3
• /
• pp.237-238
• /
• 1993

몇년 안으로 다가오는 21세기에는 정보화사회의 정착이 예견되고 있다. 정보화사회가 되면 노동조직은 단순반복적인 노동을 컴퓨터화된 제어장치가 대행하게되고, 산업구조는 대량생산에서 다양한 소비자의 욕구를 충족시켜 줄 수 있는 다품종소량체제로 변환될 것이며, 정보가 경쟁력의 원천으로 부각될 것이다. 정보화사회의 구축에는 에너지 다소비요소가 내재되어 있다. 예컨대 다품종 소량체계는 대량생산체계보다 에너지다소비형이고, 다양한 정보유통을 위하여는 대용량·고속정보통신망의 구축이 필요하게 될 것이다.

• Journal of Energy Engineering
• /
• v.2 no.2
• /
• pp.133-138
• /
• 1993

환경(Environment)이라는 단어는 인간을 중심으로 한 유형, 무형의 주위 사방을 총체적으로 포괄하는 뜻을 지닌다. 만물의 주인은 인간이라는 인간중심주의적(anthropolatric) 의미를 내재하고 있기 때문에 진정한 환경운동가들은 환경이라는 단어의 사용을 배척하고 있으며 생태중심주의적(ecocentric) 단어인 상태(ecology)를 선호한다.

• Journal of Korea Water Resources Association
• /
• v.49 no.3
• /
• pp.197-205
• /
• 2016

Recently, natural hazards have occurred frequently due to climate change. The research need for predicting variability and tendency of precipitation and temperature has been increased. However, it is difficult to determine the characteristics of precipitation and temperature within a confidence range since they change due to complex factors with choppy and too many components. If their characteristics having more than one component are decomposed, then it can be useful for determining the variation of such characteristics more accurately. In this study, Korean precipitation and temperature were decomposed and their Intrinsic Mode Function (IMF) were extracted from Empirical Mode Decomposition (EMD). Finally, the characteristics of Korean precipitation and temperature data were analyzed in terms of periodicity and tendency.

• Information and Communications Magazine
• /
• v.29 no.6
• /
• pp.41-46
• /
• 2012

전 세계적으로 에너지 소모량 절감 및 온실가스 배출 감소가 중요한 문제로 대두되고 있으며, 온실가스 배출 절감을 목표로 다양한 노력을 기울이고 있다. 우리나라도 2020년까지 국가 온실가스 감축목표를 2005년 대비 4% 감축하는 것으로 설정하고 정책입안, 기술개발 등 다양한 노력을 경주하고 있다. 연구결과에 따르면 ICT 산업은 세계 온실가스 배출량의 2%를 차지하고 있으며, 지속적으로 증가추세에 있는 것으로 조사되었다. 또한, ICT 산업이 세계 온실가스 배출량의 최대 30%를 절감할 수 있는 가능성을 내재하고 있는 것으로 조사됨에 따라, ICT 산업, 특히 네트워크 분야에서의 에너지 절감을 위한 노력의 필요성이 크게 부각되고 있다. 그린 네트워킹 기술은 ICT 분야의 핵심인 네트워킹 분야 중 에너지 효율적인 네트워킹 기술 개발을 위한 분야로, 기존 네트워킹 기술과 동일한 성능을 나타내지만 에너지를 더 적게 사용하는 네트워킹 기술을 개발하는 것을 목표로 한다. 그린 네트워킹 기술은 단말 기술, 액세스 망 기술, 백본 망 기술로 세분화 될 수 있다. 본 논문에서는 네트워크 에너지 사용량의 많은 비중을 차지하는 가입자 네트워크와 가입자 네트워크와 데이터 센터의 에너지 효율을 향상시키기 위한 기술 동향에 대해 살펴보고 국내외의 관련 표준화 기구의 표준개발 동향을 살펴본다.

• Journal of Energy Engineering
• /
• v.9 no.4
• /
• pp.309-318
• /
• 2000

핀-관 열교환기의 효율을 증대시키기 위하여는 열저항을 결정하는 데 있어서 중요한 역할을 하는 공기측 열전달 특성의 향상이 필요하다. 본 연구에서는 핀-관 열교환기의 공리측 성능을 해석하기 위해서 3차원 비압축성 Navier-Stokes 코드를 개발하였으며 이 코드는 시간항에 스칼라 내재적 근사분해법(scalar implicit approximate factorization)절차, 공간항에 유한체적법과 2차의 풍상차분법(upwind differencing)을 사용한다. 서로 다른 3개의 핀형상(평판핀, 슬릿핀, 파형핀)을 고려하였고 이들의 유동 및 열전달 특성을 연구하였다.

• Journal of Energy Engineering
• /
• v.12 no.4
• /
• pp.328-338
• /
• 2003

A study is perfomed on the difference between the volume of gas purchased from Korea Gas Corporation (KGC) and that of measured gas deliveries including total sales, pipeline inventory, and other usage by gas companies at Seoul and Kyunggi area. Actual data md information from 1996 to 2001 on gas purchase from KGC, sales, loss and own company use and pipeline status of each gas company are used to identify net inventory change in pipeline, unaccounted inventory estimates based on billing cycle and their net changes. A framework to be used for the analysis of such differences and an empirical test result are being provided. As a conclusion, the hypothesis that each gas company purchased more than the volume of gas accounted-for by all the possible factors is shown to be rejected.