• Journal of the Korean Solar Energy Society
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• v.23 no.1
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• pp.57-67
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• 2003

This study aims to presents Evaluation Method of Green Remodeling that analyze the value of environment through expense, using the method of life cycle cost and life cycle assessment simultaneously. The results of this study are summarized as follows. Evaluation Model developed in this study can convert economical value of environment into cost by integrating. In addition, the model can apply as a useful tool to estimation of economical design alternative as well as quantification of environmental loads and costs. Evaluation Model presented In this study observe energy consumption and the environmental load emission with qualification, it can forecast effect of environmental cost that cost estimation is expected to be added to energy cost rate by being possible. Synthetically, when Estimation Model and computer program that developed in this study is applies to the construction industry; reasonable management of environmental load is convenient at each step of Green Remodeling. In addition, at preliminary design phase, practical use may be possible by reasonable yardstick about various alternatives and improvement of design alternatives likewise by grasping environmental effect.

• KIEAE Journal
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• v.16 no.4
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• pp.21-30
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• 2016

Purpose: Energy saving in the built facilities is getting important due to energy crisis. The Korea government has been implemented several energy and green building policies and practices. The both of government and industry also developed green building strategies ant technologies to reduce energy consumption and carbon emission. The purpose of this research is to identify applicable green building strategies and technologies for that can be cost effective and applicable to a multiplex house. Method: This research identified appropriate green building strategies from analysing green building strategies from G-SEED certified apartment projects and popular green building strategies. This study also adopted a survey research method to find out the applicable green building strategies for a multiplex housing. In addition, this research also conduct cost estimating to identify initial cost premium of green building strategies. Results: The research outcomes in this study guide a building owner to know about initial cost premiums of green building strategies and technologies and an architect and contractor to identify appropriate and cost effective green building strategies that can be applicable to a multiplex house.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.1
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• pp.80-90
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• 2016

Thanks to superior leakage energy efficiency compared to SRAM cells, STTRAM cells are considered as a promising alternative for a memory element in on-chip caches. However, the main disadvantage of STTRAM cells is high write energy and latency. In this paper, we propose a low-cost write filter (WF) cache which resides between the load/store queue and STTRAM-based L1 data cache. To maximize efficiency of the WF cache, the line allocation and access policies are optimized for reducing energy consumption of STTRAM-based L1 data cache. By efficiently filtering the write operations in the STTRAM-based L1 data cache, our proposed WF cache reduces energy consumption of the STTRAM-based L1 data cache by up to 43.0% compared to the case without the WF cache. In addition, thanks to the fast hit latency of the WF cache, it slightly improves performance by 0.2%.

• Journal of Biosystems Engineering
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• v.24 no.4
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• pp.351-358
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• 1999

In these days, we are faced to a couple of difficult problems, the one is the unstable price of the energy due to the shortage of fossil fuel resources and the other is the serious environmental pollution from the excessive consumption of fossil fuel. In order to save the thermal energy for the house heating, in this study the heat pump using the natural thermal energy resources was provided for Ondol heating and the thermal energy consumption of the heat was compared to that of oil boiler. The results could be summarized as follows: 1. In the Ondol room the temperature difference between the Ondol surface and room air was about 5∼$10^{\circ}C$ in accordance with the ambient temperature. 2. The Ondol room heating efficiency of the heat pump with compressor of 2PS was the highest at the water flow rate of 200 l/h. 3. The energy saving rate of the heat pump to the oil boiler for heating the Ondol system was 19.3%. 4. The Ondol heating cost of the heat pump was less 20.6% than that of oil boiler when oil price was 478 won/l.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.2
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• pp.33-41
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• 2019

The purpose of this study is to provide a basic data for energy efficient apartment designs by analyzing electricity and gas usage according to horizontal locations of dwelling units in apartment buildings. The data for this research are collected from J-apartment complex, located at 'Wolbae' district in Daegu City. The data are sorted into several groups according to inner and outer locations, East-West locations, and the size of units. By the performance efficiency analysis, the study derives the result as follows: 1) generally inner units are more efficient than outer units. 2) West units are more efficient than East units. 3) The group that is most efficient in overall energy consumption is West-inner units (Group-D) and the least efficient group is East-outer units (Group-A1). 4) However, as units are getting bigger, inner units consumes more energy than outer units because of the gas usage patterns. The study also established cost analysis that shows the cost differences of usages for 30, 40, 50 years between each group. The result says Inner-outer location with East-West location affects a significant amount of the management costs. In terms of economic and social life of an apartment building, energy design standards need to be tuned and make the least efficient units perform as efficient as the most efficient units to optimize the social life of an apartment building.

• Journal of ILASS-Korea
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• v.27 no.4
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• pp.195-202
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• 2022

Recently, the global automobile market is rapidly changing from internal combustion engine vehicles to eco-friendly vehicles including electric vehicles. Among eco-friendly vehicles, LPG vehicles are low in fine dust and are suggested as a realistic way to replace diesel vehicles. In addition, it is more economical than gasoline in its class, showing a cost-saving effect. In Korea, the business of converting gasoline into LPG is active. Research is being conducted to apply this to hybrid vehicles. In this study, the difference in energy consumption efficiency was analyzed when LPG fuel was applied by selecting a 2-liter GDI hybrid electric vehicle. The operation of the hybrid system according to various driving characteristics was confirmed by selecting the WLTC mode. As a result, it was confirmed that the BSFC was about 5% lower than that of gasoline fuel when using LPG fuel. This is due to the active operation of the motor while driving. Optimization is required as battery consumption increases from an energy perspective.

• New & Renewable Energy
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• v.3 no.4
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• pp.31-37
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• 2007

Because of their low operating and maintaining costs, ground-source heat pump(GSHP) systems are an increasingly popular choice for providing heating, cooling and water heating to public and commercial buildings. Despite these advantages and the growing awareness, GSHP systems to residential sectors have not been adopted in Korea until recently. A feasibility study of a residential GSHP system was therefore conducted using the traditional life cycle cost(LCC) analysis within the current electricity price framework and potential scenarios of that framework. As a result, when the current residential electricity costs for running the GSHP system are applied, the GSHP system has weak competitiveness to conventional HV AC systems considered. However, when the operating costs are calculated in the modified price frameworks of electricity, the residential GSHP system has the lower LCC than the existing cooling and heating equipments. The calculation results also show that the residential GSHP system has lower annual prime energy consumption and total pollutant emissions than the alternative HVAC systems considered in this work.

• Journal of Korean Physical Therapy Science
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• v.15 no.1
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• pp.39-45
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• 2008

This study was undertaken to identify the influence which affect on gait speed and energy consumption regarding putting on arm sling during gait of the 40 hemiplegic patients selected from University Hospital and rehabilitation center in seoul during two months. The analysis of data was performed using the paired samples ttest to compare the differences of gait velocity, heart rate, oxygen consumption and oxygen cost in gait of preand post－ arm sling. The results of this study were as follows; 1. When comparing the result before putting on arm sling in the gait of hemiplegic patient, gait velocity after putting on arm sling was statistically significantly increased(p<.05). 2. When comparing the result before putting on arm sling in the gait of hemiplegic patient, heart rate after putting on arm sling was statistically significantly decreased(p<.05). 3. When comparing the result before putting on arm sling in the gait of hemiplegic patient, oxygen consumption per weight after putting on arm sling was statistically significantly decreased(p<.05). 4. When comparing the result before putting on arm sling in the gait of hemiplegic patient, oxygen consumption rate per weight after putting on arm sling was statistically significantly decreased(p<.05). When putting together the above result, the gait with arm sling in comparison with the gait without arm sling was to increase gait velocity, decrease heart rate, decrease oxygen consumption and was finally to decrease energy consumption in the gait of hemiplegic patient.

• Journal of Bio-Environment Control
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• v.1 no.1
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• pp.14-20
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• 1992

For the high quality and low cost agricultural crops in greenhouse cultivation, it is necessary to use natural energy as much as possible. In order to reduce the fossil fuel consumption and maximize the solar energy utilization in greenhouse heating, a latent heat storage material was developed as a relatively highly concentrative solar energy storage medium. And a solar energy-latent heat storage system was designed and constructed. The experimental research on greenhouse heating effect of the system was performed.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.05a
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• pp.83-125
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• 2007

Increasing energy costs have caused profitability problems for paper suppliers. Therefore unprofitable lines are being closed down. The actions aiming for improved profits are focused either on cost savings or on increasing the capacity of the remaining machines. The runnability of a paper machine and its total efficiency have a significant effect on energy consumption. Producing one ton of waste paper consumes at least as much energy as producing the same amount of sellable end product. New automation solutions enable significant cost-effective improvements to the total efficiency of a line without large investment projects. The measures focus on minimizing changes, interruptions, interruption recovery times and grade change times. Newest actuators, online quality measurements and wet end analysators create an improvement potential, which can be optimally implemented with the latest machine direction control solutions, based on model predictive control concepts. Equally, drying management is significant to the energy consumption. The newest control strategies optimize the use of various drying actuators for different situations; either by responding to changes as efficiently as possible or by using only the cheapest energy sources in stable situations. An even steam supply, which is vital for paper machines, is achieved with control for the power plant steam network. This makes possible to avoid the delays upon starting the paper machine and assure an even steam supply for the drying section and the actuators. This document describes means which have brought significant energy and raw material savings for paper machines. Metso Automation has provided efficiency improvement packages, which are usually based on optimized control of dry weight and drying in all running conditions. The solutions are based on performance analysis, on which the estimations for improvement potential and the necessary actions are based on. Typically benefits on an annual level have been from hundreds of thousands of euros to over one million euro. For example, variations in dry weight have been decreased more than 50%. The results are presented with a few examples. Additionally, the analysis models, adjustment solutions and the changes in running methods with which the results were achieved, are presented.