• Journal of the Korean Solar Energy Society
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• v.27 no.3
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• pp.55-61
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• 2007

This paper has been conducted to estimate cooling capacity of the dehumidification tower using hot water from a solar water heating system as a energy source of regeneration process when the dehumidification and drying system is applied to room cooling. A solar water heating system was operated and indoor temperature distributions were simulated according to weather conditions when the concerned solution was used to dehumidify room air in the dehumidification tower. Through this simulation researches we found th following results ; It was found that air velocity through supply and return diffusers should be controlled because it can cause uncomfort in dwelling area. It was found that in the sunny morning temperatures of dwelling area 1 and 2 are higher than those of dwelling area 3 and 4. In this research all the calculation results of heating and cooling system supported by solar water heater have confirmed that its cooling capacity could not reach PMV 0, thermal comfort.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.8
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• pp.19-27
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• 2018

In this study, annual site and primary energy use intensities (EUIs) and $CO_2$ emission intensities (CEIs) per area by end use were estimated based on the measurement data from June 2016 to May 2017 of 19 sample office buildings in Seoul. In addition, the estimated site EUIs by end use were compared to the U.S. Commercial Buildings Energy Consumption Survey (CBECS) 2012 data. Average site EUIs by end use were found to be in the order of electric appliance (typical floors) > heating > cooling > lighting > air movement > domestic hot water > vertical transportation > city water supply. In the case of primary EUIs and CEIs by end use, electric appliance was found to be the largest. As results of comparison with the CBECS 2012 data, it was found that the site EUIs were similar for heating, cooling, domestic hot water, and electric appliance, etc., but slightly different for lighting and air movement. The number of sample office buildings will continue to increase until 2020 (total number of samples 85) and intensities data by end use will be continuously updated through continuous collection of measurement data.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.776-781
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• 2001

To enhance thermal efficiency of thermal facility through recovery of low and medium temperature waste heat, 1MW organic Rankine cycle system was designed and developed. The exhaust gases of $175^{\circ}C$ at two 100MW power plants in pohang steel works were selected as the representative of low and medium temperature waste heat in industrial process for the heat source of the organic Rankine cycle system. HCFC-123, a kind of harmless refrigerant, was chosen as the working fluid for Rankine cycle. The organic Rankine cycle system with selected exhaust gases and working fluid was designed and constructed. From the operation, it was confirmed that the organic Rankine cycle system is available for low and medium temperature waste heat recovery in industrial process. The optimum operating manuals, such as heat-up of hot water, turbine start-up, and the process of electric power generation, were derived. However, electric power generated was not 1MW as designed but only 670kW. It is due to deficiency of pump capacity for supply of HCFC-123. So it is necessary to increase the pump capacity or to decrease the pressure loss in pipe for more improved HCFC-123 supply.

• Journal of Hydrogen and New Energy
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• v.33 no.5
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• pp.541-549
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• 2022

This study investigates anti-icing design by conjugate heat transfer analysis in lab-scale printed circuit heat exchanger (PCHE) for supply of cryogenic high pressure liquid hydrogen. The conjugate heat transfer analysis by using computational dynamics (CFD) provided various temperature distributions at important locations in PCHE heat exchanger and predicted the possibility of freezing in hot channel. And, the effect of inlet temperature of glycol water was analyzed in order to resolve the freezing problem in PCHE.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.11
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• pp.585-594
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• 2013

In this study, we developed a heat supply control algorithm that minimizes the heat loss in the heat distribution pipelines used for supplying heat energy to shared group housing. Controlling the temperature and flow rate of the hot water supplied to the heat exchanger for shared group housing enables us to develop a heat supply control technique that meets the heating load required by each household in a shared apartment building in accordance with changes in the outdoor air temperature, and that minimizes the heat loss occurring in the heat distribution pipeline. A one-year study in 2008 on a 1,473-household D-apartment building in Hwaseong, Gyeonggi-do, South Korea, compared the heat capacity used by each household, as well as the heat capacity supplied to the heat exchanger room of the apartment housing building, to calculate the amount of heat loss in the heat distribution pipeline. The results confirmed that 24.1% of the heat supplied was lost in the piping.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.12
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• pp.1779-1787
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• 2000

Southern and south-western Australia is a typical mediterranean environment, characterised by wet, cold winters and dry, hot summers. The evaporation rate varies significantly in summer, resulting in a high salinity of drinking water for grazing animals. In addition, a large amount of land in the cropping areas is affected by salt. Puccinellia, tall wheat grass and saltbushes have been planted to improve the soil condition and to supply feed for grazing animals. Animals grazing these areas often ingest an excessive amount of salt from soil, forage and drinking water which can reduce feed intake, increase the water requirement, depress growth and affect body composition as demonstrated in sheep. While the deer industry has been successfully developed in these regions, the potential impact of excessive salt intake on deer production is unknown. The salt tolerance has been well defined for sheep, cattle and other livestock species, but the variation between animal species, breeds within species, maturity status and grazing environments makes it impossible to apply these values directly to deer. To optimise deer production and effectively use natural resources, it is essential to understand the salt status of grazing deer and the impact of excessive salt intake on growth and reproduction of deer.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.18 no.4
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• pp.33-44
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• 2022

In this study, we analyze the existing heating and cooling operation method for an office-type complex building with a central heating and cooling system, and examine the effects of applying various EMS that can be applied according to the load size to save energy in the building. For this purpose, simulation analysis was performed. As a control method, reset control of chilled water, hot water, cooling water and supply air temperatures, optimal start/stop of heat source, and number of heat source control were applied according to the load size, and energy consumption was analyzed accordingly. In addition, when all of these control methods were applied, the overlapping energy saving effect was finally confirmed. As a result, it was possible to confirm the energy saving effect when EMS for reset control and heat source control were applied compared to the existing control method of the heating and cooling system, and the effect for the case of using all these control methods in combination was also confirmed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.6
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• pp.669-674
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• 2012

D-Cube City is a recently completed multi purpose building consisting of four types of facilities; offices, a department store, a hotel, and congregation spaces. A community energy supply system(CES) has been installed to supply this building with electricity, steam, heat, and cold water. The BEMS, building energy management system, is currently being designed to reduce building energy consumption through the efficient operation of the various pieces of building service equipment. In this study the optimal methods for operating the CES of D-Cube City were considered. This system includes three combined heat and power systems, seven steam boilers, two hot water boilers, two absorption chillers, and four turbo chillers, and various other pieces of equipment. In result, the optimal methods of operating the CES for various energy demand levels were obtained along with the seasonal effects on the economic efficiency of the operation. The effect of the amount of energy demanded by the various facility areas on the total energy consumption was also analyzed.

• Korean Journal of Veterinary Service
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• v.33 no.4
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• pp.393-399
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• 2010

We analyzed the HACCP prerequisite of National Veterinary Research and Quarantine Service (NVRQS) and the Food Establishment Inspection Report of US Food and Drug Administration (FDA) to recommend contents and ranges to be complemented and used for preparation of guidelines for more effective application of HACCP prerequisites. We used the HACCP inspection reports implemented by Korea Livestock Products HACCP Accreditation Service from 2007 to 2009, FDA Food Code 2009 Guide 3-B Instructions for Marking the Food Establishment Inspection Report, and Retail Food Establishment Sanitation Requirements of 410 Indiana Administrative Code. Major non-compliance items were open doors and windows, insanitary cleaning of in-use utensil, inadequate record of warehousing, and improper storage, transportation, and labelling. Hot water supply, personal hygiene, and regular product testing were additional week points which should be more strongly controlled by detailed operating guidelines. Also, current prerequisite items were required revision into more precise contents to enhanced the effective evaluation and practical application in meat markets.

• Journal of the Korean Solar Energy Society
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• v.32 no.3
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• pp.59-67
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• 2012

In this paper, performances of solar hot water supply systems are parametrically analyzed with the variations of solar collector area, slope of collector and volume of storage. All simulations are conducted by using TRNSYS computer program. Average solar fractions, collector efficiencies and temperatures of storage are investigated monthly as well as annually. For system analysis, the maximum value of monthly average solar fractions has a limitation of 90 percent. As a result, the designed solar thermal system with $6m^2$ collector area, $50^{\circ}$ slope and $0.36m^2$ storage volume could provide almost an annual average solar fraction of 72 percent. By increasing the storage volume to $0.42m^2$, the annual solar fraction of system increases up to 73 percent.