• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.5
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• pp.72-76
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• 2012

In this paper, the capacity criteria have been proposed in order to select a cooperative relay node in WSNs, under the environment where direct path has a poor link gain. This process may ensure the efficiency improvement of signal transfer between source and destination and reduction of energy consumption as well. Two criteria are incorporated to select a cooperative relay node. Firstly, calculate the energy gain ratio between the relay path and the direct path. Secondly, investigate the effects of relay node's usage in WSNs through the simulation in terms of energy consumption. In the simulation, the relationship between energy consumption and direct path gain, uniformly generated in the certain range and its positive effects have been identified.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.282-287
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• 2011

Of school buildings, university building requires various case analysis unlike buildings in the elementary, middle and high schools in accordance with its characteristic for variables such as characteristic of department, construction structure and material, the number of persons admitted and schedule. Through the case research on the 'D' university located in Daejeon, this study made a comparison on the monthly and yearly consumption of gas and electricity of the most recent 3 years and implemented analysis on the usage pattern and standby power of air conditioning and heating by the hour and month using PCCS(Power Consumption Consulting System) as respects electricity that is considered to have a possibility of energy-saving. The result of analysis showed that enormous amount of electric power was used during the night time for freeze protection and burst in winter season and standby power was increased in winter season as a result.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.270-276
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• 2012

In this study, thermally coupled distillation system and conventional two-column process were investigated for extractive distillation. The two processes were simulated and optimized using Aspen plus. Objective function for the optimization was energy consumption and optimization results to reduce energy consumption were used to get guidelines for design and operation for the two extractive distillation processes. Comparison of these two processes showed that thermally coupled distillation system provided better energy efficiency and lower capital cost than conventional distillation system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4253-4259
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• 2015

In this study, the effects of various control methods of outdoor air cooling control system on control characteristics and energy consumption in building are researched by simulation. The system analysis modelling is done by using TRNSYS program package, and the control performances with existing outdoor air cooling methods are compared with the control ones without outdoor air cooling. As a result, appropriate operating temperature conditions of outdoor air cooling system according to outdoor temperature changes are required, and the outdoor air/return air dry bulb temperature comparison control method among the control methods shows best responses in energy savings.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.368-374
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• 2019

Objectives: To examine the associations of borg's scale with actual heart rates of workers and energy consumption during their physical work. Methods: A total of 72 workers performing physical activities in postal service, ceramic manufacturing, and metal manufacturing participated in heart rate measurement for 1 work shift using the activity meter(A360) and responded to a borg's scale questionnaire. Results: In consistent with previous findings, we presented high correlation between borg's scale and energy consumption measures among workers performing physical activities(r=0.89) while post-work average heart rate showed nearly no correlation with post-work borg's scale (r=0.09). We proposed a set of adjustments when using borg's scale to estimate physical workload for those workers engaged in physical activities during the majority of their work shift. Conclusions: Our findings suggest that a caution should be paid to when using Borg's scale to estimate heart rates during physical activities as well as energy consumption as the product of heart rate measurements.

• Environmental and Resource Economics Review
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• v.24 no.1
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• pp.109-139
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• 2015

Referring to many previous research on the statistical differences in the figures of energy balance table between that of KEEI and IEA, a study is conducted to provide with a framework for proper comparison, followed by the actual calculation of the differences. Major differences are found for energy oil with its size of over 32% differences in primary energy supply and in energy transformation sectors. In final energy consumption sector, naptha consumption for petro-chemical industry shows 14.58% differences. Overall final energy consumption figure of KEEI after its adjustment to net calorific value as is the case of that of IEA is 3.58% larger than that of IEA. Considering the fact that energy balance table provides the basic information for the understanding of energy sector, further studies seem to be necessary for proper adjustment of current status.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.5
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• pp.315-327
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• 2013

Wireless Body Area Network (WBAN) is a network around a human body within 3~5m which consists of medical or non-medical device. WBAN has to satisfy many kinds of demands such as low-power, a variety of data rate and a data priority. Especially, it is hard for the nodes for monitoring vital signs to replace battery. Thus energy and channel efficiency is important because the battery power is limited. In this thesis, a novel algorithm for reducing the energy consumption is proposed. The proposed algorithm adjusts transmission period according to traffic. by means of determining transmission period by amount of data, the node can reduce energy consumption. Energy detection is performed in order to guarantee data priority before attempting to transmit. In case of failing to transmit, it is proposed that energy consumption is reduced through avoiding collision by changing priority. The comparison result shows that the proposed algorithm reduces power consumption and increasing maximum channel efficiency by avoiding collision.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.33-42
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• 2018

The aim of this study was to examine the association between egg consumption and the risk of chronic disease in Korean adult females using the 2013 Korea National Health and Nutrition Examination Survey. A total of 1,230 subjects aged 40~64 were classified into the 4 groups according to the number of egg consumed per week: <1, 1~2.9, 3~5, ${\geq}5.1$ As egg consumption increased, the intake of energy, protein, fiber, cholesterol, calcium, potassium, riboflavin, and vitamin C increased. The percentage of the subjects with lower intake of energy, protein, calcium, iron, vitamin A, riboflavin, niacin, and vitamin C than the estimated average requirement in the <1 group were the highest among the groups. The blood lipid profile including total cholesterol and LDL-cholesterol was not significantly different among the 4 egg groups. The higher egg consumption was inversely related to a lower odds ratio of metabolic syndrome, hypertriglycemia, hyperglycemia, hypoHDL-cholesterolemia, and hypertension. This result indicates that egg consumption does not elevate the plasma cholesterol level and has a beneficial effect of decreasing the risk of chronic disease. (175)

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.749-752
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• 2012

Recent social issues is energy issues, green computing has attracted attention. Active research on the power consumption of computer profiling is one of the various approaches for green computing. As a representative tool PowerAPI, PowerTop, JouleMeter, pTop, and EnergyChecker. These studies can be used to measure the power consumption of each computer device because it is based on a pure software. Based on this profiling process at the level of power consumption by performing the power consumption of each program can be analyzed. Therefore to identify the processes that consume a lot of power and control the total power consumption by reducing, also when designing the program, based on data profiling power enables the design of low-power programs, and ultimately can be oriented green computing. In this paper, by comparing and analyzing the associated representative studies, the ideal process level will draw on the characteristics of the power consumption profiler.

• 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.