• Journal of the Korean Solar Energy Society
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• v.39 no.2
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• pp.57-69
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• 2019

Because the hospital building operates 24 hours a day, 365 days a year for treatment and restoration of patients, it has a different pattern of energy use than that of ordinary buildings. Hospitals contribute to energy consumption and have a negative environmental impact. This study aims to find how meaningful energy performance, reflecting good energy management and ECMs, can be operated for hospital buildings, a category encompassing complex buildings with different systems and large differences between them. In this study, we proposed the energy diagnosis & evaluation method and energy management process to verify energy saving through operation data based on system & facility characteristics, operation pattern and energy consumption characteristics of hospital building. Energy consumption structures were surveyed throughout 4 reference hospital in Seoul, Korea. Findings confirm that different hospital departments have hugely different energy-demand profiles. Energy efficiency and energy saving potentials are presented. The energy performance analysis can be applied to a wide range of problems in energy-system operation.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.1
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• pp.37-46
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• 2019

The energy of the building is influenced by the user 's activity due to the population, society, and economic characteristics of the building user. In order to obtain accurate energy information, the difference in the amount of energy consumption by the activities and characteristics of building users should be identified. The purpose of the study is to identify the difference in the amount of energy consumption by the user's activities in the same building, and to analyse the relationship between user's activities and demographic, social and economic characteristics. For research, energy simulation is performed based on actual user activity schedule. The results of the simulation were clustered by using K-Means clustering, a machine learning technique. As a result, four types of users were derived based on the amount of energy consumption. The more energy used in a cluster, the lower the user's income level and older. The longer a user's indoor activity times, the higher the energy use, and these activities relate to the user's characteristics. There is more than twice the difference between the group that uses the least energy consumption and the group that uses the most energy consumption.

• 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 Energy Engineering
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• v.23 no.3
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• pp.66-71
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• 2014

Oil is obviously vital for economic growth and industry development. This paper attempts to explore whether or not there is a inverted-U relationship between oil consumption and economic growth. To this end, we employ a panel data analysis with fixed effect or random effect models using the set of data from 61 countries for the year 1990-2008. In conclusion, a statistically significant inverted-U relationship between per capita consumption of oil and per capita GDP is found. However, the level of per capita GDP at the peak point of per capita oil consumption is estimated to be 65,072 in 2005 international constant dollars, which is much larger than economic scales of sampled countries. Thus, as per capita GDP grows, per capita oil consumption is predicted to increase until eventually reaching the peak.

• 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.

• KIEAE Journal
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• v.10 no.6
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• pp.21-26
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• 2010

This study is to suggest basic data for the policy on the energy demand and management of an U-based city compliant with characteristics of regions and districts in future city by conducting research on the energy consumption and management of an U-based city, considering city energy demand characteristics focused on the center district of Daegu metropolitan city. U-based city energy consumption and management solution is considered to be effective in establishing the guideline of environment-friendly urban architecture planning as well as the assessment of energy consumption characteristics in a city.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.6
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• pp.338-345
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• 2013

The purpose of this study is to analyze the correlation between the 'Fenestration Energy Consumption Efficiency Rating System' (hereafter referred to as FECERS) and building energy consumption. 'EnergyPlus' was used for the calculation of energy consumption in apartments and office buildings, according to FECERS's rating and SHGC. The result indicates that the FECERS has high correlation with apartments, but has low correlation with office buildings. Also, it indicates that office buildings have a large impact from SHGC, which is not reflected in the FECERS. Consequently, the FECERS needs to be improved, by adding optical properties to assessment items. Additional study is required to establish the fenestration rating system, which, on the basis of this work, has high relevance to building energy consumption.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.11a
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• pp.261-265
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• 2008

To solve the lack of housing, our country has supplied an enormous volume of apartments, and these days it occupies 75% of our buildings. As apartments occupy most of our housings, the rate of energy usage from them are also high. On this, setting apartment energy reduction as a target, by researching the actual conditions of energy consumption and drawing a basis data, we can apply this as a way of saving energy, rationalization of the scale of energy supply facilities and a standard when planning facilities. To grasp the present condition of energy usage of the urban rental apartment, this research analysed the use of electricity, gas and water monthly and annually of a rental apartment that is located in Daegu. The results showed that in 2003 the electricity usage was 1,198MWh but 1,315MWh in 2007, which means 9% of electricity usage increases every year. The average of water usage was $85,072m^2$ per year and they used $604.2MJ/m^2$ Typical energy consumption unit on $74.4m^2$ of area and $448.8MJ/m^2$ on $105.8m^2$. By showing the usage of energy and water of the urban rental apartment, understanding the tendency and preparing an Typical energy consumption unit standard through this research, apartments should use energy more efficiently.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.8
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• pp.432-439
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• 2015

Current building procedures seek to minimize external air supplies to reduce the energy consumption of air conditioning, resulting in a high dependency on mechanical ventilation. We therefore studied an economizer-cycle system, whereby the introduction of external air saves energy. We analyzed different economizer-control methods, addressing mixed-air temperatures and outdoor-air fractions according to outdoor-air temperatures; also, we analyzed the energy consumption of the three economizer-cycle control types using detailed EnergyPlus simulation modeling. A differential enthalpy control method showed a lower energy consumption range from 5.8% to 6.2% than that of other methods during the simulated period. A differential dry-bulb control method showed a 12.7% lower energy consumption than the no-economizer method in the intermediate period, but also showed 7.1% more energy consumption during the summer period. When latent heat was not removed due to high summer humidity, we found a significant level of resultant energy consumption.

• Architectural research
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• v.19 no.1
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• pp.7-11
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• 2017

Energy consumption in university building has steadily increased over the last decade, and a strong upward trend in recent years. This study was undertaken to analyze the relationship between energy consumption and their affecting factors, six academic buildings were considered. The factors limited to heating and cooling, which is the main end use (nearly 60 per cent of total energy consumption in university buildings), encompassing system and operating schedules (user activity) and area use. To understand how to building is used, operated and managed, walk-through assessment was conducted as well as interview with university staff. The results show that the energy consumption of the humanities building was somewhat smaller than the consumption of the science and engineering building, and its range was from $31.26kgoe/m^2$ to $23.52kgoe/m^2$, depending on heating and cooling system and area use. And the energy consumption of the science and engineering building was related to operating schedules (user activity) as well as laboratory equipment characteristics. More analysis on a larger number of buildings is required in the future, including building form and material performance level to generalize the significant factors influencing building energy consumption.