• Proceeding of Spring/Autumn Annual Conference of KHA
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• 1994.05a
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• pp.45-50
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• 1994

The energy consumption in apartment houses is investigated according to the heating systems, that is, district, central, and individual heating systems. And, operating conditions of intermittent heating are surveryed and analysed in the central heating systems. As a result, each annual energy consumption of district, central and individual heating system is 143.56 Mcal/m2year, 216.78 Mcal/m2year and 150.68 Mcal/m2year, Also, the heating is generlly started at 04:00 and 17:00 of each day, and the heating system is operated for 2~3 hours per each time.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.463-468
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• 2005

An experimental study on the optimal control algorithm for central heating system for minimizing energy consumption while maintaining the comfort of indoor thermal en vironment in terms of the environmental variables such as loads and weather. experimental study has been done by one using the prototype of central heating system. As a result the optimal control algorithm shows good energy performance in comparison with conventional control one.

• Journal of the Korean housing association
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• v.14 no.3
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• pp.85-92
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• 2003

Considering the present development situation of rental apartment since 1982, the supply of homeless housing for low-income dwellers has contributed a amount of quantities, but has been deficient qualities in housing policy. To propose the energy policy for low-income dwellers, this study investigated the energy consumption and the degree of heating satisfaction by heating system through questionaries in permanent rental apartment and 50 year period rental apartment complexes. The results of this study were as follows; The annual energy consumption of heating and hot water supply is 267.2 Mca1/$\textrm{m}^2$ㆍyr in central heating system, is 163.9 Mca1/$\textrm{m}^2$ㆍyr in unit heating system. But from the view of annual energy cost and the degree of heating satisfaction, central heating system were better than unit heating system in rental apartment.

• Journal of the Korean housing association
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• v.15 no.1
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• pp.33-40
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• 2004

Considering the present development situation of rental apartment since 1982, the supply of rental housing for low-income dwellers has contributed a amount of quantities, but has been deficient qualities in housing policy. To propose the device of remodeling for low-income dwellers in deteriorated apartment, this study investigated the energy consumption of central heating system and the characteristics of maintenance cost in permanent rental apartment. The results of evaluation of alternative heating systems by Life Cycle Costing in permanent rental apartment were as follows; From Life Cycle 15∼20 years by Present Worth Method, the economic heating system of remodeling is central heating system (heat source: B-C oil), unit heating system(natural gas), central heating system(natural gas) in order.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.5
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• pp.459-466
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• 2004

In order to save the energy in apartment houses, it is essential that the energy amount consumed in heating per household should be surveyed and analyzed according to heating method, which can be classified into unit, central and district methods. As a basis, we selected the household with nominal area of 32 py. because it accounts for the most percentage in Korea. It is estimated that the gas amount for cooking is 90 ㎥ and the energy amount for hot water supply is 11.41 GJ for a year, which is necessary to calculate the heating energy. Through the survey of actual energy consumption in Seoul and Gyeonggi, the energy amount used in heating can be obtained according to the heating type: 26.02 GJ/year for the unit heating, 28.09 GJ/year for the central heating and 40.61 GJ/year for the district heating.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.2
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• pp.140-146
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• 2005

The on-line optimal control algorithm for central heating system has been researched for minimizing energy consumption while maintaining the comfort of indoor thermal environment in terms of the environmental variables such as indoor heating load and outdoor temperature variation. This study has been done by using TRNSYS Program in order to analyze the central heating system. The optimal control algorithm shows good energy Performances in comparison with the conventional one.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.7 no.1
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• pp.38-44
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• 2011

In this study, heating performance and energy consumption characteristics with control strategies for central heating system were researched by the simulation. The simulation analysis is made by TRNSYS ver. 15 with the actual data. The parametric study on proportional factor, control time interval and outdoor air temperatures changes were done to compare control characteristics and energy performance, respectively. As a result, the simulation results with various parameter changes show good heating performance and energy saving.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.7 no.1
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• pp.32-37
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• 2011

In this study, control characteristics and energy performance with flow rate control methods were reviewed with the simulation. The heating system is classified such as fan coil unit and HVAC system currently used in buildings with valve control and pump inverter control. The simulation analysis program is made by TRNSYS ver. 15 with the actual data. As a result of this study, the central heating system with pump inverter control decreases electricity energy and reduces gas consumption. Inverter control method shows better performance in comparison with valve control one for energy saving.

• The Korean Journal of Food And Nutrition
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• v.33 no.4
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• pp.440-446
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• 2020

The purpose of this study was to derive the conditions for manufacturing rice porridge with optimum properties after reheating. The characteristics of rice porridge according to the soaking time, water addition rate, heating temperature, heating time, and cooling conditions were compared using the 'Samkwang' cultivar. In Step I, as the heating temperature increased, the weight change decreased and the viscosity increased, and the temperature known as the main factor of the gelatinization also appeared to affect the viscosity increase. In Step II, the viscosity and the texture properties was not significantly different as the soaking time was reduced, and 10 minutes was suitable because of due to the shortening effect of the total process time. In Step III, the residual heat was lowered by cooling after the rice porridge production, so the viscosity could be greatly reduced. Also, it was confirmed that the water addition rate of 900% and the heating temperature of 15 minutes were optimal manufacturing conditions. The next study will investigate the porridge processability of rice cultivars using these results.

• The Journal of Sustainable Design and Educational Environment Research
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• v.11 no.2
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• pp.19-27
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• 2012

This study was carried out in order to establish the estimation equation for school power consumption using regression analysis based on collected power consumption for two years of weather data and schools are located in Central Changwon and Masan district in Changwon city. (1) The power consumption estimation equation for Heating and cooling is calculated using power consumption per unit volume, the difference between actual power consumption and results of estimation equations is 4.1%. (2) The power consumption estimation equation for heating load is showed 2.6% difference compared to actual power consumption in Central Changwon and is expressed 2.9% difference compared to that in Masan district. Therefore, the power consumption prediction for each school using the power consumption estimation equation is possible. (3) The power consumption estimation equation for cooling load is showed 8.0% difference compared to actual power consumption in Central Changwon and is expressed 2.9% compared to that in Masan district. As the power consumption estimation equation for cooling load is expressed difference compared to heating load, it needs to investigate influence for cooling load.