• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.6
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• pp.793-798
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• 2010

In this paper we propose a low-power walking compensation method for biped robot based on consumption energy analysis. Firstly, basic walking motions that can reduce energy consumption of robot movements are implemented based on consumption energy analysis according to robot axes. We define knee bent motion as a basic walking motion. It can improve energy consumption and motion stability by lowering center of gravity of the biped robot. We analyze consumption energy of left and right leg of the robot using motor currents and propose a compensation method of walking motions to reduce unbalance of consumption energy between left leg and right leg. It can also improve energy consumption and walking stability of the robot. The proposed low-power compensation method based on consumption energy analysis is verified by walking experiments of a small biped robot with an embedded system.

• Journal of Family Resource Management and Policy Review
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• v.14 no.3
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• pp.53-68
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• 2010

This study tried to develop the theoretical backgrounds, explaining consumers energy consumption behavior and analyzed its effects. In other words, this study investigated the factors influencing the amount of electronic energy consumption. In this study, we used 678 questionnaires which were selected a quota sampling by living area who were above 20 years old and married. Summary of results of this study follows. First, attitude for energy saving was positively related with female, high school graduated large size of family members, elderly, and middle-class consumers. In addition, consumers' search for energy saving were appeared passively in young consumers under 30 years old, and the family with the highest household income. Consumers' purchasing energy-efficient products was presented in large size of family members, and young consumers. Second, consumers' environmental oriented behavior, action-directed behavior, healthseeking behavior were significantly related with energy saving behavior, and active information search for energy saving, but not with purchasing energy-efficient products and consuming behavior of electrical energy. Third, the quantity of electric energy consumption was affected by the size of family members, the living size of house related with high energy demand, the attitude for energy saving, and searching information for energy-saving.

• Journal of the Korean Solar Energy Society
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• v.34 no.4
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• pp.75-81
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• 2014

In this paper we made energy consumption units of glass curtain wall type apartment and general apartment in Busan metropolitan city and compared energy consumption characteristics by building envelope. The monthly electricity consumption units of general apartment were shown in the range of $1.16{\sim}1.51kWh/m^2{\cdot}mon$ which were indicated higher value in January, February, August and September with little variation. On the other hand, in case of glass curtain wall type apartment, monthly electricity consumption units were represented in the range of $1.91{\sim}7.07kWh/m^2{\cdot}mon$ with significant fluctuations monthly, which were outstandingly high in July, August and September. The monthly city gas consumption units of general apartment were found to be in the range of $1.79{\sim}18.07MJ/m^2{\cdot}mon$, while glass curtain wall type apartment were within $0.94{\sim}19.91MJ/m^2{\cdot}mon$. City gas consumption units from December to March were shown highly in both type apartments. The monthly energy consumption units of general apartment were found to be within $14.23{\sim}30.69MJ/m^2{\cdot}mon$, while glass curtain wall type apartment were within $24.49{\sim}68.9MJ/m^2{\cdot}mon$. Energy consumption units of glass curtain wall type apartment were suggested 4.84 times higher than those of general apartment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.2
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• pp.17-23
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• 2004

The effects of refining consistency and plate gap on the specific energy consumption and physical properties of liner were investigated. Higher refining consistency and narrower plate gap brought about the reduction of specific energy consumption to decrease the freeness. Refining consistency and plate gap did not affect the bulk, Taber stiffness and compression index. The reduction of freeness and/or the increase of specific energy consumption caused the decrease of bulk and Taber stiffness, but increased the compression index. The effect of grammage on bulk was not observed, but Taber stiffness and compression index were increased with grammage. The bulk was decreased with the reduction of freeness rapidly at the above 400 mL CSF, and then levelled off. It is expected that the reduction of energy consumption could be obtained from the application of higher refining consistency and narrower plate gap during refining.

• Journal of Korea Planning Association
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• v.53 no.6
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• pp.101-116
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• 2018

Paying an attention to the issue of energy poverty of low-income households and ensuing regressivity of energy consumption, this study empirically analyzes the effects of both household and housing characteristics on heating energy consumption in an integrated way and identifies their causal structure based on the 2016 Korea Housing Survey data provided by the Korean government. Multiple regression analysis shows that household income and deteriorated level of housing, such as age and degree of cracks have positive effects and floor area of housing has a negative effect on the heating energy consumption per unit area of housing (HECPUH). Path analyses further reveal that the direct effect of household income on HECPUH is offset by the indirect effects that are mediated by deteriorated level and floor area of housing, making the total effect statistically insignificant. As a result, there is no significant difference in HECPUH across all income strata, implying that low-income (high-income) households pay more (less) heating costs relative to their income level, since they reside in the houses with relatively low (high) energy efficiency. To deal with this regressive causal structure of energy consumption, a policy option is recommended to improve energy efficiency of low-income housing through the government assistance in its maintenance and repair.

• Asian Journal of Atmospheric Environment
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• v.8 no.1
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• pp.48-58
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• 2014

Energy efficiency is vital to improve energy security, environmental and social sustainability, and economic performance. Improved energy efficiency also mitigates climate change by lowering greenhouse gas (GHG) emissions. Buildings are the single largest industrial consumer of energy and are therefore key to understanding and analyzing energy consumption patterns and the opportunities for saving energy at the district level in urban environments. This study focused on two representative boroughs in the major metropolitan area of Seoul, South Korea as a case study: Gandong-gu, a typical residential district, and Jung-gu, a typical commercial district. The sources of the energy supplied to the boroughs were determined and consumption patterns in different industry sectors in Seoul used to identify current patterns of energy consumption. The study analyzed the energy consumption patterns for five different building categories and four different sectors in the building using a bottom-up energy modeling approach. Electricity and gas consumption patterns were recorded for different building categories and monthly ambient temperatures in the two boroughs. Finally, a logarithmic equation was developed to describe the correlation between commercial activity and cooling energy intensity in Jung-gu, the commercial district. Based on these results, recommendations are made regarding the current energy consumption patterns at the district level and government energy policies are suggested to reduce energy consumption and, hence, greenhouse gas emissions, in both commercial and residential buildings.

• Journal of Korean Public Health Nursing
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• v.29 no.1
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• pp.102-114
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• 2015

Purpose: This study was conducted in order to identify consumption status, risk awareness and experience of adverse effects of high caffeine energy drink among university students. Methods: This study was a descriptive survey including 270 students in 2 universities and 7 colleges in D metropolitan city. Consumption Status, Risk Awareness and Experience of Adverse Effects of High-Caffeine Energy Drink tools were developed by literature review. Data analyzed using descriptive statistics and $x^2$-test. Results: In the results, 86.7% of the students had previous experience of energy drink consumption and male students and smokers had more experience of energy drink consumption than female students and nonsmokers. The reason of energy drink consumption was increasing alertness for studying. 45.7% of the students were aware of the risk of high caffeine energy drink and the first risk was sleep disturbance. 51.1% of students were experienced adverse effects, mainly palpitation and sleeplessness. Conclusion: The results suggest a need to increase awareness of adverse effects and potential risks of high caffeine energy drink consumption in university students. In addition, university and government should provide education and campaigns to prevent excessive high caffeine energy drink consumption.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.4
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• pp.459-469
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• 2016

Gas hydrate desalination process is based on a liquid to solid (Gas Hydrate, GH) phase change followed by a physical process to separate the GH from the remaining salty water. The GH based desalination process show 60.5-90% of salt rejection, post treatment like reverse osmosis (RO) process is needed to finally meet the product water quality. In this study, the energy consumption of the GH and RO hybrid system was investigated. The energy consumption of the GH process is based on the cooling and heating of seawater and the heat of GH formation reaction while RO energy consumption is calculated using the product of pressure and flow rate of high pressure pumps used in the process. The relation between minimum energy consumption of RO process and RO recovery depending on GH salt rejection, and (2) energy consumption of electric based GH process can be calculated from the simulation. As a result, energy consumption of GH-RO hybrid system and conventional seawater RO process (with/without enregy recovery device) is compared. Since the energy consumption of GH process is too high, other solution used seawater heat and heat exchanger instead of electric energy is suggested.

• The Korean Journal of Food And Nutrition
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• v.29 no.6
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• pp.899-910
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• 2016

The purpose of this study was to determine factors related to the consumption of energy drinks among male and female high school students in Daejeon. The research data, derived from the self-administered questionnaire method, was collected from 664 students in fifteen high schools during the spring of 2016. A total of 542 complete questionnaires were analyzed (response rate: 79.8%). Approximately 73% of the students self-reported having consumed energy drinks, with a greater percentage of male (as opposed to female) students self-reporting as having done so. The most common reasons given for the consumption of energy drinks were to stay awake (54.8%), the good taste of the drink (28.0%), to concentrate during studying (17.2%), and to relieve fatigue (16.9%). The adverse effects were palpitation (59.3%), insomnia (35.6%), and experiencing difficulty in waking up (30.5%). More than two in three (67.8%) students who experienced adverse effects still consumed energy drinks. The average level of health consciousness was lower than 3 out of 5 points. The results of the logistic regression analyses indicated a positive relationship between monthly allowance (OR=1.01 for male and female students) and the consumption of energy drinks by both male and female students. Among the male students, freshmen (OR=0.23) were less likely to have consumed energy drinks than juniors. Male students' sleeping hours (OR=0.65) and perceived school life satisfaction scores (OR=0.63) were negatively associated with the consumption of energy drinks. In the case of female students, study hours (OR=0.83) and energy drinks consumption were negatively related. These factors affecting energy drinks consumption could be considered in the development of dietary education programs aimed at protecting high school students from the adverse health impacts of energy drinks.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.4
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• pp.626-648
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• 2011

Energy consumption of wireless access networks is in permanent increase, which necessitates development of more energy-efficient network management approaches. Such management schemes must result with adaptation of network energy consumption in accordance with daily variations in user activity. In this paper, we consider possible energy savings of wireless local area networks (WLANs) through development of a few integer linear programming (ILP) models. Effectiveness of ILP models providing energy-efficient management of network resources have been tested on several WLAN instances of different sizes. To cope with the problem of high computational time characteristic for some ILP models, we further develop several heuristic algorithms that are based on greedy methods and local search. Although heuristics obtains somewhat higher results of energy consumption in comparison with the ones of corresponding ILP models, heuristic algorithms ensures minimization of network energy consumption in an amount of time that is acceptable for practical implementations. This confirms that network management algorithms will play a significant role in practical realization of future energy-efficient network management systems.