• KIEAE Journal
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• v.12 no.6
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• pp.29-38
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• 2012

The current building energy efficiency rating certification regulation on apartment houses evaluates only the saving rate of energy consumed during operation, i.e. use, of a building, but doesn't consider the energy consumptions and environmental load($CO_2$) emissions occurring during the whole lifetime of a building. So this study calculated the energy consumptions and environmental load emissions occurring during the whole lifetime of a building, selected reference schemes and alternative items by design variables to present a design draft considering energy efficiency and environmental performance, and evaluated the total cost by combining and calculating its direct cost(material and heating cost) and indirect cost(environmental cost), for an existing apartment house as an evaluation object. As a result of analysis, the change of heating cost by alternative items of design variables showed a 4~8% change rate compared to the reference scheme, and the material cost of design variable 7 showed a maximum 4.4 times change rate in the alternative plan 6 compared to the reference scheme. The environmental cost showed a similar change rate to the material cost change rate in general, but showed a similar environmental cost change rate to the heating cost change rate in case of design variables 4-1, 4-2, 7.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.4
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• pp.245-251
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• 2008

The cooling load in winter is significant in buildings and hotels because of the usage of office equipments and the high efficiency of wall insulation. Hence, the development of a multi-heat pump that can cover heating and cooling simultaneously for each indoor unit is required. In this study, the operating characteristics and performance of a simultaneous heating and cooling heat pump in the heating-main operating mode were investigated experimentally. The system adopted a variable speed compressor with four indoor units and one outdoor unit with R-410A. In the heating-main mode, the cooling capacity was lower than the design cooling capacity due to the reduction of the flow rate in the indoor unit for the cooling, with the increase of the heating capacity. To solve these problems, the performance characteristics of the simultaneous heating and cooling heat pump in the heating-main mode were investigated by varying the flow rate to the indoor unit for the cooling and the compressor rotating speed. In addition, the adequate control methods were suggested to improve the system efficiency.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.678-681
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• 1999

The objective of this study was to evaluate the effect of different heating rates on the thermal properties of pork loin muscle by DSC. Pork loin muscle was subjected to programmed heating at the following heating rate: 5, 10, 20, 30 and $40^{\circ}C/min$. Peaks were progressively shifted to right side as the heating rate was increased. $T_0$ was $50.39^{\circ}C$ at $5^{\circ}C/min$ and it was increased to $57.45^{\circ}C$ at $40^{\circ}C/min$ (p<0.05). Total enthalpy was 3.52 J/g at $5^{\circ}C/min$ and total enthalpy was increased to 3.60, 4.14, 4.54 and 4.61 J/g by degrees at heating rate 10, 20, 30 and $40^{\circ}C/min$ respectively.

• Journal of Korean Clinical Nursing Research
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• v.14 no.2
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• pp.47-57
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• 2008

Purpose: The purpose of this study was to examine the effects of an electric heating pad on abdominal pain and anxiety during the colonoscopy procedure. Method: Data were collected from 70 adult patients (experimental group (35), control group (35)) who underwent colonoscopy in a general hospital in Seoul, South Korea between January 6 and May 4 2006. For the experimental group the electric heating pad was applied from 20 minutes before the test through the whole procedure. Objective pain was measured during the test, and subjective pain, state anxiety, blood pressure and pulse rate were measured after the procedure. Results: The experimental group with the electric heating pad reported significantly lower subjective pain and anxiety than did the control group. There were no significant differences in objective pain between experimental and control groups. Patients with an electric heating pad showed significantly lower systolic and diastolic pressure than did those in the control group. There was no significant difference in pulse rate between the groups. Conclusion: Use of an electric heating pad was efficient in reducing subjective pain and anxiety among patients undergoing colonoscopy. This is a convenient and useful nursing intervention to reduce anxiety and pain among patients having a colonoscopy.

• Journal of Biosystems Engineering
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• v.24 no.4
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• pp.351-358
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• 1999

In these days, we are faced to a couple of difficult problems, the one is the unstable price of the energy due to the shortage of fossil fuel resources and the other is the serious environmental pollution from the excessive consumption of fossil fuel. In order to save the thermal energy for the house heating, in this study the heat pump using the natural thermal energy resources was provided for Ondol heating and the thermal energy consumption of the heat was compared to that of oil boiler. The results could be summarized as follows: 1. In the Ondol room the temperature difference between the Ondol surface and room air was about 5∼$10^{\circ}C$ in accordance with the ambient temperature. 2. The Ondol room heating efficiency of the heat pump with compressor of 2PS was the highest at the water flow rate of 200 l/h. 3. The energy saving rate of the heat pump to the oil boiler for heating the Ondol system was 19.3%. 4. The Ondol heating cost of the heat pump was less 20.6% than that of oil boiler when oil price was 478 won/l.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.3
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• pp.131-136
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• 2013

The present study has conducted cycle design and control technology of a water source VRF heat pump system. Previously, study of a simultaneous heating and cooling in an air source VRF heat pump system has been conducted. However, performance data and design methods for simultaneous heating and cooling in a water source VRF heat pump system are limited in the literature, due to various system parameters and operating conditions. In this study, the operating characteristics and performances of a simultaneous heating and cooling heat pump system are carried out, in simultaneous operation modes. Control logics of an EEV are developed for flow rate control to the outdoor unit, and are verified. When the control logics are applied, the simultaneous cooling and heating performances are sufficiently achieved, and system COPs are increased by up to 23.4%.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.109-113
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• 2003

Low pressure or vacuum carburizing(LPC) has undergone major further developments since 1980 and now it has achieved industrial maturity. The advantage of low pressure vacuum carburizing over gas carburizing is not only the creation of surface entirely free of oxide and environmentally friendly but also a reduction in batch times, lower gas and energy consumption and the prevention of soot. In this study the experiment was carried out to investigate the effects of vacuum atmosphere in the heating furnace. Heat transfer rate and uniformity of temperatures of test samples in the pressure range of a few 0.1torr was examined on a test charge of 100kg. It is found that the fuel saving rate due to decreasing heating time reach to 20% in the vacuum heating mode as compared with atmospheric heating mode. Also the uniformity of temperatures in the samples was improved significantly in the vacuum heating mode. Also the effects of the RC fan for stirring atmosphere inside furnace was examined. Results shows RC fan appears to provide a reasonable tool for improving uniformity of temperature in the atmospheric heating mode.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.10
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• pp.235-243
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• 2019

In South Korea, millions of poultry have died due to repeated heat waves every year. The purpose of this study is to analyze the characteristics of heating and cooling loads of chicken houses in Korea and to present an effective insulation and ventilation measures to minimize the damage of poultry due to summer heat wave and to save energy in chicken houses in winter. The heating and cooling loads of standard chicken house were calculated. As a result of the calculation of maximum heating load based on the minimum ventilation rate in winter, the outdoor air temperature requiring heating was $6{\sim}7^{\circ}C$ to keep the indoor air temperature of chicken houses as $24^{\circ}C$. The peak cooling load of chicken houses was mostly taken by the heat generated by chickens and the heat gain due to ventilation. The heat gain through building envelopes was as small as neglectable. Most of chicken houses is usually cooled by gigantic forced ventilation in summer in Korea. When the chicken houses are cooled by electric cooling machine such as cooler or air conditioner, it is more effective to keep minimum ventilation rate to reduce the maximum cooling load. To lower the temperature of supplying water to cooling pad, it is recommended to use the underground water below 10 meters from the ground if there is abundant underground water.

• Analytical Science and Technology
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• v.28 no.5
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• pp.353-360
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• 2015

Boiling is an efficient removal method to reduce radon in groundwater when ventilating indoor air. 13 groundwater samples with various radon concentrations were used to evaluate the reduction rate of radon with heating temperature and time. The groundwater samples were obtained by Bladder pump and on-situ measurements such as dissolved oxygen (DO) and hydrogen concentration (pH) and so on were carried out by a flow cell system isolated from the ambient atmosphere environment. All samples for measuring radon in groundwater were analyzed by liquid scintillation counter (LSC). The experiment result showed that increasing groundwater temperature enhanced radon removal rate but the initial radon concentration with high level lowered the removal rate. This means that radon reduction in groundwater by heating needs more heating energy and longer heating time with radon concentrations. Radon removal rate in groundwater, therefore, mainly depends on the initial radon concentration, heating temperature, and heating time.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.5
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• pp.71-79
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• 2016

The effects of spot heating for growing the strawberry cultivated in a plastic greenhouse during the winter that were estimated in Nonsan strawberry experiment station located in Chungnam. The temperature of water for heating was controlled by a electric hot water boiler and kept at the range of $22{\sim}24^{\circ}C$. Heating pipes were set up in root zone for root zone heating and very close to crown for crown heating. Spot heating effects were estimated by applying spot heating system in three test factors of heating root zone, crown only and crown plus root zone. The material for crown heating pipe was white low density polyethylene and the nominal diameter of that pipe was 16 mm. The material for root zone heating pipe was flexible stainless steel and the nominal diameter of that pipe was 15A. The flow rate of heating water circulation was 480 L/h and water circulation lasted for all day long. Temperatures, harvest yield by test beds were surveyed from Nov. 10, 2013 to Apr. 29, 2014. The temperature of crown spot for crown heating bed was at the range of $13.0{\sim}17.0^{\circ}C$ during the night and that of crown spot in control bed was at the range of $8.0{\sim}14.0^{\circ}C$. Also, the temperature of root zone for root zone heating bed was at the range of $18{\sim}21.0^{\circ}C$ and that of root zone in control bed was at the range of $13.0{\sim}15.0^{\circ}C$. The cumulative yield growth rate in earlier harvest period (from Dec. 20 to Mar. 15) of crown heating bed was 43% compared with that of control bed and the cumulative yield of crown plus root zone heating bed was 39 % and that of root zone heating bed was 39 %.