• Earthquakes and Structures
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• v.23 no.2
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• pp.139-150
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• 2022

In most self-center braces, decreasing residual deformation is possible only by increasing pretension force, which results in lower energy dissipation capacity. On the other hand, increasing energy dissipation capacity means higher values of residual deformation. The goal of this research was to find the best design for a self-centering buckling restrained brace (SC-BRB) system by balancing self-centering capability and energy dissipation. Three, six, and nine-story structures were investigated using OpenSees software and the TCL programming language to achieve this goal. For each height, 62 different SC-BRBs were considered using different values for the pretension force of cables, the area of the buckling restrained brace (BRB) core plate, and the yield stress of the core plate. The residual deformation and dissipated energy of all the models were calculated using nonlinear analyses after cyclic loading was applied. The optimum design for each height was determined among all the models and was compared to the structure equipped with the usual BRB. The residual deformation of the framed buildings was significantly reduced, according to the findings. Also the reduction of the energy dissipation was acceptable. The optimum design of SC-BRB in 6-story building has the most reduction percent in residual deformation, it can reduce residual deformation of building 83% while causing only a 57% of reduction in dissipated energy. The greatest reduction in residual deformation versus dissipated energy reduction was for the optimum SC-BRB design of 9-story building, results indicated that it can reduce residual deformation of building 69% while causing only a 42% of reduction in dissipated energy.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.115-120
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• 2009

The studies for mechanical performance development have been examined to reduce energy consumption in building construction field. However, The energy consumption using in building for heating is impacted by not only system performance but also PMV particularly at temperature and clo. Most energy using in building part is mainly consumed for heating and cooling to keep comfort temperature. Heating energy consumption is bigger than cooling energy in Korea because of temperature difference in winter in comparison with summer at apartment building. This means that energy consumption can be changed by occupancy's comfort setting temperature in apartment building. This study evaluate actual comfort temperature range by clo and examined heating energy consumption by Esp-r and CO2 reduction possibility. The results show that keeping ASHRAE standards can reduce heating energy up to 23%; also, wearing underclothes with ASHRAE standard can reduce heating energy up to 47.8%. Option 4 showing Maximum CO2 emission reduction indicates that kerosene. LNG and electricity can reduce 1.5t, 1.7t, 2.46t respectively in comparison with option 2.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.422-430
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• 2018

Increase in oil prices and building energy consumption has been a great burden for Korea which has significant energy dependence on foreign energy sources. In this context, reduction of building energy consumption, which comprises 40% of total energy consumption, is a very important issue. This research therefore empirically analyzed a hospital "P" that implemented ICT-based energy consumption and cost reduction initiative. The hospital first replaced existing water absorber for heating/cooling air and boiler for heating water with water heat storage heat pump system. This was accompanied by subscribing to different electricity price plans to maximize cost reduction. Secondly, the hospital additionally applied ICT-based optimized control algorithm that considers surrounding factors (external temperature, changes in energy demand). The analysis of these mechanisms indicate that the ICT-based energy consumption and cost reduction initiative for hospitals can reduce energy consumption by 53.6% with replacement of low-efficiency equipment and additionally by 18.2% with optimized control algorithm. The mechanisms will provide energy consumption reduction opportunities for other hospitals and buildings with high energy consumption.

• KIEAE Journal
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• v.15 no.4
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• pp.37-43
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• 2015

Purpose : The study applied control strategy to reduce through optimal control and operation of pump by applying control on variable speed to the circulation pump of HVAC system in the office building. The study has the purpose to review validity of control on variable speed as ESMs(Energy Saving Measures) and establish the control technology on variable speed pump. The study performed reduction analysis of building energy and economic evaluation of pump through energy effectiveness control strategy of HVAC system. Method: The study sought possible reduction through energy control strategy which can provide proper flow fitting to building load by applying control on variable speed pump. The study applied control strategy to reduce through pressure differential set-point control and operation of pump by applying control on variable speed to the circulation pump of HVAC system in the office building. Result : The results showed that about 16-35% of pump energy could be saved by using these optimal control strategies. In the result of analysis on 10 years life cycle cost of analysis on payback period of initial investment pump, variable speed pump control showed 5.1 years.

• Journal of the Korean Solar Energy Society
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• v.33 no.2
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• pp.28-34
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• 2013

It is essential to reduce building energy consumption in office building because government enact policy which encourages building energy certification from 2013. Office building has high cooling energy demand due to large glazed area of facade in these days. Shading devices can be an alternative of reducing high cooling energy demand. So, this study simulated a variety of exterior venetian blinds to know how much building energy be affected by orientation and reflectance of slat. The results of this study are based on Seoul weather data. The following is a summary of this study. 1) As a slat of venetian blinds has the lower reflectance, the more building energy reduced. Reflectance is usually affected by color and material of slat. In case reflectance is 0.2 reduce 4% of building energy than reflectance is 0.8. 2) Horizontal exterior venetian blinds are more effective than vertical exterior venetian blinds in all of orientation. Horizontal shape is average 16% more effective in shading effect than vertical shape. 3) In this case study, the most effective shading device is low reflectance horizontal exterior venetian blinds that result about 18% building energy reduction than no shade model. The results of this research can be used to plan shading devices for energy conservative office building.

• Architectural research
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• v.19 no.4
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• pp.89-94
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• 2017

In Korea, it is necessary to improve the performance of buildings with respect to the energy efficiency while improving the quality of occupants' lives through a sustainable built environment. During the design and development process, building projects must have a comprehensive, integrated perspective that seeks to reduce heating, cooling and lighting loads through climate-responsive designs. The aim of this study is to assess the optimal window-to-wall ratio of multi-rise residential units in the early design phase in Korea. The study analyzed the variation of annual heating and cooling energy load in two apartment prototype units located in Seoul city using different WWRs. The analysis was conducted using Autodesk Ecotect Analysis 2011 tool. The study found for total annual building load reductions WWR on the south and north face should be studied independently based on the room function. It also found reducing the WWR for bedrooms and windows on the northern façade resulted in reduced total annual building load.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.3
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• pp.104-117
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• 1998

Rising concern about climate change has evoked interest in the potential for urban vegetation to help reduce the level of atmospheric CO\sub 2\, a major heat-trapping gas. This study quantified the functio of home energy savings and carbon emission reduction by shading, evapotranspiration and windspeed reduction of urban vegetatioin in Chuncheon. Tree and shrub cover averaged approximately 13% in residential land. The effects of shading, evapotranspiration and windspeed reduction annually saved heating energy by 2.2% and cooling energy by 8.8%. The heating and cooling energy savings reduced carbon emissions by 3.0% annually. These avoided emissions equaled the amount of carbon emitted annually from fossil fuel consumption by a population of about 1,230. Carbon emission reduction per residential building was 55kg for detached buildings and 872 kg for multifamily buildings. Urban vegetation annually decreased heating and cooling energy cost by ￦1.1 billions, which were equivalent to annual savings of ￦10,000 savings and carbon emission reduction due to tree plantings in the wrong locations, while windspeed reduction had a great effect. Plantings fo large trees close to the west and east wall of buildings, full tree plantings on the north, and avoidance of shade-tree plantings or selection of solar-friendlytrees on the south were recommended to improve the function of building energy savings and carbon emission reduction by urban vegetation.

• KIEAE Journal
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• v.15 no.3
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• pp.37-42
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• 2015

Purpose: Apartment is a typical residential type in Korea. In the past, apartment types were very monotonous. But today, the types of complex are changed because personal needs have been diversified and personalized. In order to meet those needs, construction companies are constructing various types of apartments. The more apartment types are diverse, the more the energy problems are taken place. So, the purpose of this study is to solve the problem of energy gap in the same complex through improving the thermal transmittance of wall. Method: Heating energy consumption of Building Energy Efficiency Rating System and heating energy usage of apartment show a similar trend on the graph. In order to identify the best position of heating energy consumption difference reduction, we change the building's U-value of front, back, side walls. Result: In the A complex, maximum and minimum heating energy consumption building's shapes are flat. the best efficiency is side U-value change and the worst is front change. In the E complex, maximum heating energy consumption building's shape is tower and minimum building shape is flat. Consequently, the front and back wall performance change was little effect to reduce energy gap, while the change of side wall's U-value show the great reduction between building's energy consumptions.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.813-818
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• 2008

In order to reduce energy consumption, this study presents a way to energy reduction through energy-feedback which enables a household to self-recognize the need for energy reduction and respond to. The effect of this energy-feedback has been reported as $10{\sim}15%$ in average, and been actively investigated in abroad from 1970's while study in korea has been in its first step. In this study, examination on the cases of abroad study is made as it shows the effectiveness and applicability of energy feedback. And paradigms to consider for application to korea will be suggested anticipating the change of actions through energy feedback.

• Journal of Construction Engineering and Project Management
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• v.1 no.1
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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.