• Journal of the Korean Society for Advanced Composite Structures
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• v.4 no.2
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• pp.15-24
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• 2013

This project is mainly related to evaluation of total energy consumption of low energy house, the exterior envelope of which was wholly composed of structural insulated panels(SIP). The U-value of applied SIP was in the range of 0.189 to $0.269W/m^2{\cdot}K$ and the U-value of pair glass from 0.78 to $1.298W/m^2{\cdot}K$ was applied for window dependent to its function respectively. For comparison of total energy performance, the energy simulation for pilot house was performed to compare with the control house having insulation criteria of Korean building regulation in 2009. Based on simulation of dynamic energy performance, the pilot house saved 48.3% of annual energy consumption while the control house in 2009 consumed as 85.7GJ/y. In case of heating, the result showed that the energy saving ratio amounted to 76.7%. For $CO_2$ emission, the pilot house diminished approximately 35.4% from $6,208.4kgCO_2$ to $4,009.2kgCO_2$. In payback period to early investment, it was analyzed the pilot house took 7.8 years, when the low energy house built by other insulation method with same thermal perfusion took 11.5 years. From this result, it is considered that the SIP is more effective, economic to Green Home application.

• Journal of Climate Change Research
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• v.2 no.2
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• pp.115-131
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• 2011

Out of all the possible actions that can be taken to respond to greenhouse gas reduction, including development of greenhouse gas reduction technology, infrastructure, actions to improve energy saving and efficiency, and offset with carbon emission reductions (CERs), this study shall focus on the investment on CERs. This study will take a look at risks involved with investing in CERs such as UN registration refusal risk and CERs price fluctuation, and will design risk management model which shall be verified. The goal of this paper is to provide optimized CERs investment strategies for different types of investors, such as general trading companies seeking for investment opportunities and financial companies with plans for green products development and investment by preparation for carbon market. It is expected that the global competitiveness of domestic financial companies shall be improved by taking actions on carbon market instead of previous passive response to climate change and that Korea, the number two Carbon Emissions supplier and number one derivatives market in terms of volume, shall be able to lead the worldwide carbon market.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.6
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• pp.109-113
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• 2020

Against the backdrop of low-carbon, green growth, many attention is focused on a sustainable society where humans and nature coexist. Carbon emissions increase with energy consumption, which is 40 percent of the world's energy consumption by buildings. Korea has a plan to make zero-energy houses mandatory only for new buildings in 2025, but it is relying on private technology investment for its technology. The reality is that the current technology costs more than 1.5 times more than general buildings, and private companies do not have many zero-energy house complexes other than experimental houses. This study aims to study the new model of zero energy house by introducing IOT system that efficiently observes and controls energy in zero energy house, monitoring pleasant environment on the web and introducing resident proper temperature maintenance system.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1259-1264
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• 1990

During the past two decades, a lot of researches have been done on the synthesis of grassroot heat exchanger networks(HEN). However, few have been dedicated to retrofit of existing heat exchanger networks, which usually use more amount of utilities (i.e. steam and/or cooling water) than the minimum requirements. This excess gives motivation of trades-off between energy saving and rearranging investment. In this paper, an algorithmic-evolutionary synthesis procedure for retrofitting heat exchanger networks is proposed. It consists of two stages. First, after the amount of maximum energy recovery(MER) is computed, a grass-root network featuring minimum number of units(MNU) is synthesized. In this stage, a systematic procedure of synthesizing MNU networks is presented. It is based upon the concept of pinch, from which networks are synthesized in a logical way by the heuristics verified by the pinch technology. In the second stage, since an initial feasible network is synthesized based on the pre-analysis result of MER and must-matches, an assignment problem between new and existing units is solved to minimize total required additional areas. After the existing units are assigned, the network can be improved by switching some units. For this purpose, an improvement problem is formulated and solved to utilize the areas of existing units as much as possible. An example is used to demonstrate the effectiveness of the proposed method.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.927-939
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• 2012

Cool roofs are currently being emerged as one of important mechanism to save energy in relation to the building. Although green roof has already gained nation-wide recognition as a typical method of energy saving in the roof, this approach did not provide a realistic evidence that is economically feasible in terms of installation cost. This research is primarily intended to compare installation cost between the two techniques. This research proposes a comparative evaluation framework in a more objective and quantitative way for an installation cost between the two techniques. Kyungpook National University (KNU) was selected as a survey objective and an exhaustive and realistic comparison of installation cost between the two techniques was conducted, based on Life Cycle Cost analysis (initial investment cost, maintenance cost, dismantling and waste disposal expense). It was possible to identify that installation cost of cool roofs is 4.7 times cheaper than that of green roof. Also present value based on probabilistic approach was identified as 0.25 (4.95) higher than the installation cost on the assumption of constant price and interest. It is expected that much more installation cost for the large scale green roof will be required since small-size green roof selected as a survey objective in this study could be operated under less initial installation and maintenance condition.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1036-1041
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• 2008

Double facade systems are often paid attention of as an effective energy saving measure for curtain wall buildings. However, it is not easy to install the system in existing buildings and requires substantial investment. An innovative double window system is proposed in this study which can be installed with exiting window systems in a cost effective way. the proposed system is connected to existing return ducts to make airflow between the existing window and the newly installed window. To ensure the best performance of the proposed system, simulation-based analysis was implemented in which airflow characteristics of inside double window were examined according to air pressures of return duct and window material by using computer simulation ESP-r. the overview of the proposed system and the results of the simulation-based analysis are presented in this paper.

• Korean Journal of Organic Agriculture
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• v.20 no.3
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• pp.267-282
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• 2012

In this study, RPS system, one of the renewable energy support systems, is utilized for economic analysis of solar generation equipment and the fuel cost savings plan for controlled horticulture farms with high fuel-cost dependency and facility applicability were evaluated. On the exterior of the upper layer of glass greenhouse (9917$m^2$) of controlled horticulture farms using bunker C oil, half of the area (4958$m^2$) was utilized for theoretical installation and operation of 450kW-level solar power generator, and as the result, first, the effect of investment cost only of solar generation system was found to be quite excellent, but it was analyzed that there were limits to saving the fuel costs of the controlled horticulture farms. Second, when geothermal system was first introduced in the farm and solar system was additionally introduced, it was analyzed that the effect of introducing solar system was excellent. In order to apply such effects to the sites of farming, partial supplementation of RPS system which is being uniformly applied regardless of the purpose of renewable energy is necessary. When the subject of use directly install facilities where it is directly connected to national added-value such as food security created by the farming industry, it is necessary to introduce appropriate system that corresponds to such. Moreover, it was studied that the quick development of demonstrative complex that can practically evaluate the applicability of renewable energy in farming industry and interest and preparation of related institutions in financial support structure for its site application would lead to success.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.294-301
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• 2018

In winter, thermal screens are widely used to reduce heat loss from greenhouse to save energy. Unfortunately, not much data are available to the farmer to compare thermal screens while selecting the one that meets their specific requirements. Thus, there is a need to investigate the thermal performance of thermal screens. To address this issue, the Building Energy Simulation (BES) model of a hot box was used to calculate the overall heat transfer coefficient (U-value) of the thermal screens. To validate the model, computed and experimental U-values of single-and double-layered polyethylene (PE) material were compared. This validated model was used to predict the U-values of the selected thermal screens under defined weather conditions. We quantified the U-values of each selected material and significant changes in their U-values were noted in response to different weather conditions. Notably, the thermal properties of the tested screens were taken from the previous literature to calculate U-values using the BES model. The U-values of the thermal screens can help researchers and farmers evaluate their screens and make pre-design decisions that suit their investment capabilities.

• Clean Technology
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• v.7 no.1
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• pp.43-49
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• 2001

To meet $CO_2$ emission regulation, this study describes the present state of $CO_2$ reduction technology and the effect of the regulation on power industry. In Japan, R&D investment is actively continuing through a long-term R&D project, along with trying to meet the reduction demand by the ways of energy saving and abroad business. EU has made a lot of investments in increasing the efficiency of power generation and developing alternative energy sources. The US is making provision of the portion of reduction by using energy saving program and emission trading, and the current DOE-driven program is addressing the development of cost-effective power systems. In the country, the research to reduce $CO_2$ emission has been mainly driven by the government and research institute supported by the government. Meanwhile, if the reduction obligation imposed on Portugal which is the least strict condition will be enforced in Korea, it is likely that about 50 running power plants should be stopped or shut down after 2015, in spite of voluntary reduction efforts such as conversion to clean fuels, etc. according to the government's long-term electric power need and supply plan.

• Journal of the Korean Institute of Gas
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• v.24 no.1
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• pp.17-22
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• 2020

Light Naphtha is distillated from crude oil unit and separated into the methane, ethylene and propylene by boiling point difference in sequence. This separation is conducted using a series of binary-like columns. This separation method is known that the energy consumed in the reboiler is used to separate the heaviest components and most of this energy is discarded as vapor condensation in the overhead cooler. In this study, the first two columns of the separation process are replaced with the Petlyuk column. A structural design was exercised by the stage computation with ideal tray efficiency in equilibrium condition. Compared with the performance of a conventional system of 3-column model, The design outcome shows that the procedure is simple and efficient because the composition of the liquid component in the column tray was designed to be similar to the equilibrium distillation curve. The performance of the new process indicates that an energy saving of 12.1% is obtained and the cost savings of 44 million won per day based on gross domestic product is reduced under same total number of trays and the initial investment cost is saved.