• Journal of the Korean Solar Energy Society
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• v.34 no.6
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• pp.93-102
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• 2014

The aim of this study is to analyze the influence of various factors on energy consumption of apartment buildings. Energy consumption data of the Green Together, integrated building energy management system maintained by the government were used, and end-use and primary energy consumption data of 2012 were analyzed for 181 apartment complexes completed between 2004 and 2011 in Seoul. Energy consumption by use, source and heating type were analyzed. Then, energy consumption trends were analyzed and suggested according to energy efficiency ratings, number of households, areas for exclusive use, number of floors, core types, building types, orientations and completion years.

• Advances in Energy Research
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• v.3 no.2
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• pp.71-80
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• 2015

This paper describes nuclear energy technologies for the solution of long term energy problem with better reliability. A short overview about nuclear energy applications are explained with a basic analysis of energy. Furthermore, industrial application, space application of nuclear systems and ship propulsion in nuclear energy application are demonstrated in more detail. This report also includes some examples of the experienced nuclear power plant to identify energy production. The general purpose of the article is to understand how efficiently nuclear systems generates energy, and solve the world's increasing energy demand in our century.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.7
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• pp.27-34
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• 2018

The energy consumption of apartment houses is affected by various factors. The criteria for assessing current energy usage are area, region and purpose. The purpose of this study is to obtain the reliability of the method of evaluating the existing energy consumption certificate and to derive usable evaluation factors according to the correlation of factors affecting energy consumption. The research process collects energy usage data for apartment houses in Daegu and calculates statistical results through correlation analysis and multiple regression analysis. As a result, it was found that the power energy is influenced by the yearly factor of physical characteristics, and the heat energy and total energy usage are influenced by the energy source which is energy characteristic factor.

• Journal of the Korean Data and Information Science Society
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• v.19 no.4
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• pp.1091-1100
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• 2008

The purpose of this study is to find out how energy substrate's utilizations in the maximal exercise-cardiorespiratory function and the energy metabolic variation- have the effect on before and after the supplements of coenzyme Q10(100mg per day for 8 weeks) based on the male students(CoQ10=8, placebo=8) of high school. The results of this study are as follows: Maximal oxygen uptake and maximal oxygen per weight are found to have the significant increase respectively in supplement group. Glucose is found to have the significant decrease after the supplement of CoQ10. And then FFA is found to have the significant increase. In the above results, the supplements of CoQ10 and cardiorespiratory function in the maximal exercise are found to have the improvement. CoQ10 in the anaerobic exercise spares the energy's utilization of Glucose and then is found to have the increase of the utilization of FFA. CoQ10 in the aerobic exercise is reported to have the increase of the utilization of FFA and then CoQ10 in the maximal exercise is also recognized to have the increase of the utilization of FFA, or energy substrates.

• Journal of the Korean Solar Energy Society
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• v.39 no.5
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• pp.29-40
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• 2019

In response to the rapid climate change, in order to save energy in the field of buildings, the country is planning not only zero energy buildings but also zero energy cities. In the Urban Development Project, the Energy Use Plan Report is prepared and submitted by predicting the amount of energy demand at the planning stage. However, due to the activation of zero-energy buildings and the increase in the supply of new and renewable energy facilities, the energy consumption behavior of buildings in the city is changing from the previous ones. In this study, to estimate urban energy demand of Zero Energy City, building energy demand forecasts based on "Passive plans for use of energy based primary energy consumption", "Actual building energy usage data from Korea Appraisal Board" and "data from Certification of Building Energy Efficiency Rating" as well as demand forecast according to existing "Consultation about Energy Use Plan Code" were calculated and then applied to Multifunctional Administrative City 5-1 zone to compare urban total energy demand forecasts.

• Solar Energy
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• v.19 no.1
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• pp.37-45
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• 1999

As polymer added in flow, the phenomenon of drag reduction effect was found by many experiments and studies. We divided polymer into three molecular weight($2{\times}10^5,\;4{\times}10^5,\;5{\times}10^5$) and into four concentration(1, 5, 10, 20wppm), then we measured the drag reduction effect in the range Reynolds Number with $30000{\sim}60000$. Finally we found that the most effect drag reduction was that molecular weight is $2{\times}10^5$ with 10wppm concentration. Then the concentration was according to PEO molecular weight, and in general DR increase according to Reynolds Number.

• Progress in Superconductivity
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• v.13 no.1
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• pp.40-46
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• 2011

A superconductor flywheel energy storage system (SFES) is an electro-mechanical battery which transforms electrical energy into mechanical energy for storage, and vice versa. A 10 kWh class flywheel energy storage system (FESS) has been developed to evaluate the feasibility of a 35 kWh class SFES with a flywheel $I_p/I_t$ ratio larger than 1. The 10 kWh class FESS is composed of a main frame, a composite flywheel, active magnetic dampers (AMDs), a permanent magnet bearing, and a motor/generator. The flywheel of the FESS rotates at a very high speed to store energy, while being levitated by a permanent magnetic bearing and a pair of thrust AMDs. The 10 kWh class flywheel is mainly composed of a composite rotor assembly, where most of the energy is stored, two radial and two thrust AMD rotors, which dissipate vibration at critical speeds, a permanent magnet rotor, which supports most of the flywheel weight, a motor rotor, which spins the flywheel, and a central hollow shaft, where the parts are assembled and aligned to. The stators of each of the main components are assembled on to housings, which are assembled and aligned to the main frame. Many factors have been considered while designing each part of the flywheel, stator and frame. In this study, a 10 kWh class flywheel energy storage system has been designed and constructed for test operation.

• 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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.10
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• pp.551-557
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• 2017

Most European economies, Japan, and many governments have made it a major policy to expand the green business by disseminating heat pump technology, which has a large $CO_2$ reduction effect. The heat pump of all heat sources has been recognized as renewable energy and the policy to encourage has been implemented. In the recently revised Renewable Energy Law, the hydrothermal source (surface sea water) heat pump was newly included in renewable energy. In addition, the scope of application of heat pumps has expanded in the mandatory installation of renewable energy for new buildings, remodeling buildings, and reconstructed buildings based on this law. However application to heat pumps using all natural energy as heat source has been put off. In this revision, the ratio of renewable energy to the total energy produced by the heat pump was fixed at 73%, which depends on coefficient of performance of heat pump. The ratio of renewable energy is $1-1.8/COP_H$, and should be calculated including the coefficient of performance of the heat pump. Using a high efficiency heat pump or a high-temperature heat source increases the coefficient of performance and also reduces $CO_2$ emissions. It is necessary to expand the application of heat pumps as renewable energy equipment and to improve the correct calculation of renewable energy production.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.5
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• pp.531-538
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• 1993

A 4-week energy balance study was conducted to estimate the energy expenditure (EE) of 16 primary school age boys and girls, 8 to 12 year age, by measurement of energy intakes and changes in body energy (BE) content (intake / balance technique), keeping their normal living pattern and eating behavior. Gross energy intake (GE) and fecal energy (FE) loss was measured by bomb calorimetry. Urinary energy (UE) loss was calculated from nitrogen excreted. Fat mass (FM) was determined from body density estimated from skinfold thickness. Mean constitutional ratio of carbohydrate, protein and fat for the total energy intake was 10.1 $\pm$1.8%, 12.2$\pm$0.1% and 17.1$\pm$2.0% for the boys and 74.0$\pm$1.7%, 10.7$\pm$0.3% and 15.3$\pm$0.5% for the girls, respectively. Fecal energy loss was 5.1% and 4.5% proportion of the gross energy intake for the boys and girls, respectively. Mean daily metabolizable energy estimated by subtract feral and urinary energy loss was 1862$\pm$15kcal for the boys and 1627$\pm$20kcal for the girls. Total body energy change estimated from body composition change over 28 days was increased 1524$\pm$539kcal for the boys and 3622$\pm$718kcal for the girls. Mean daily energy expenditure was 1812$\pm$37kcal(52 $\pm$2kcal/kg of body weight) for the boys and 1487$\pm$25kca1 (52$\pm$2kcal/kg of body weight) for the girls.