• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.1
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• pp.88-93
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• 2005

In this study, the operational characteristics on heating performance and energy consumption for intermittent hot water heating system in apartment buildings were research by simulation. The effects of apartment inlet hot water temperature and operation time per day on energy consumption and indoor thermal environment are investigated. The strategy of energy saving and thermal environment improvement is suggested in comparison with the existing ones.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.6
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• pp.55-62
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• 2007

Actual states of energy utilizations were investigated and analyzed on three representative rural villages in Chungcheongnam-Do. Rural residents were almost using the ondol boiler as a heating facility and oil(diesel, kerosene) and electricity(night thermal-storage power service) as a heating energy. There were a few households using briquette or firewood in a fuel hole with Korean hypocaust. Most of their cooking facilities were gas ranges using LPG. The most popular hot-water supply system was an oil boiler and the next was an electricity boiler. The amount of energy use in a rural household generally showed 20,000 to 40,000 won/month of the electric power rate, 400 to 800 liter/year of the oil and 60 to 120 kg/year of the LPG. Prompt measures should be taken to promote the spread of new and renewable energy such as solar heat, biomass and wind power, etc.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.5
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• pp.218-223
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• 2014

Korea District heating corp. recently give an attention to combine the district heating and supply pipes as a two pipe system that are in the present system separated with room heating and warm water supply pipe, and the two pipe system is commonly applied for heating service in European countries. In the new two pipe system, only one heat source is supplied to a house and partitioned into room heating and warm water supply by household substation. So the effective distribution of supplied heat source in accordance to user intention is very important. This paper presents the development and performance test of three-way proportional control valve for a combined heat source system in district heating. The proposed valve is controlled to partition heat source into two different directions : hot water distributor for space heating and household substation for warm water supply in response to the pressure drops of tap water caused by the user. The performance investigation is shown within 3% of error compared to the theoretical model of the three-way proportional valve and its controllability is verified.

• Culinary science and hospitality research
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• v.20 no.2
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• pp.89-99
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• 2014

This study aims to make stock using cod bones with the hot water extraction method. Moisture content, chromaticity, pH, salinity, sugar content, mineral contents, quantitative analysis, and overall acceptance were studied to determine the standard formula. The results are as follows. The moisture content decreased (p < 0.001) and color value increased as heating time increased. The pH was highest in CS5 which was heated for 30 minutes and lowest in CS1. The salinity and sugar content significantly increased with more heating time (p < 0.001). In terms of mineral contents, sodium was highest in 138.87~154.17 mg, magnesium and iron showed proportion difference with increased heating time. The mineral analysis test result revealed that sodium, magnesium and iron showed proportional difference with increased heating time, while potassium and calcium did not change. The result of quantitative analysis test showed transparency, fishy smell, delicate flavor, savory flavor, salt taste and umami taste became stronger as high-pressure heating time increased. From these result, CS4 was evaluated to be the best in appearance, flavor, taste, aftertest and overall acceptance. Also, 60 minute high-pressure heating time is the most desirable to produce stock using cod bones as a main ingredient.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.116-123
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• 2010

The Study of the Railway-saving electric water heaters to replace electric heaters when combined, Separate bathroom with hot water in winter, as coaches, without the need to warm up with hot water may be.To improve passenger service can tell. High-efficiency energy saving energy from furnace. Due to fuel cost savings and business improvements come true. Can prevent pollution.Heating the room next to railway vehicle utilization is expected to nopeulgeot.Is expected to expand gradually.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.4
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• pp.163-168
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• 2014

The plate heat exchanger has been widely used in water heating systems due to high efficiency, simple structure, and easy maintenance. However, the studies on the effects of fouling on the heat transfer performance under various operation and maintenance conditions are very limited in the open literature. The objective of this study is to investigate the effects of fouling with calcium carbonate ($CaCO_3$) on the heat transfer characteristics of the plate heat exchanger under various operating and geometric conditions. The heat transfer coefficient and pressure drop in the plate heat exchangers were measured under accelerated fouling conditions with $CaCO_3$ by varying geometric and operational parameters. The fouling resistance increased with the decrease in the flow rate, and the increase in the chevron angle and the concentration.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2148-2153
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• 2007

The electricity conversion-efficiency of solar cell for commercial application is about 6-15%. More than 85% of the incoming solar energy is either reflected or absorbed as heat energy. Consequently, the working temperature of the photovoltaic cells increases considerably after prolonged operations and the cell's efficiency drops significantly. PV/T refers to the integration of a PV module and a solar thermal collector in a single piece of equipment. By cooling the PV module with a fluid steam like air or water, the electricity yield can be improved. At the same time, the heat pick-up by the fluid can be to support space heating or service hot-water systems. In this study, a pulsating heat pipe solar heat collector was combined with single-crystal silicon photovoltaic cell in hybrid energy-generating unit that simultaneously produced low temperature heat and heat and electricity. This experiment was investigating thermal and electrical efficiency for evaluation of a PV/T system.

• Journal of Society of Preventive Korean Medicine
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• v.22 no.1
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• pp.45-59
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• 2018

Objectives : The purpose of this study is to present trends and contents of herbal Korean Medicine patches by analyzing the herbal patches in Korean patents. Methods : Electronic search for herbal patch patents was conducted in KIPRIS (Korea Intellectual Property Rights Information Service). Korean patents that were registered by January 1, 2018 were selected in study. Patents that were not using herbal medicine or not related to patch were excluded in this study. The applicant, application date, International Patent Classification (IPC), contents and adhesive site of patches, target diseases, model of experiment and extraction methods were analyzed. Results : A total of 17 patents were included in this study. In applicant analysis, 61.5% of applicants were corporations. All IPCs in patents were involved in Section A (Human necessities & Agriculture) and 66.7% of IPCs were A61K (Preparations formedical, dental, ortoiletpurposes). In types of patch, 8 patents were hydrogel patches (47.1%), followed by 3 heating patches (17.6%). Skin related symptoms were the most targeted diseases (52.9%), Human was the most used model in experiments. Solvent extraction and hot water extraction were used frequently, and some patents had no limit for extraction were also existed. Conclusions : The study results will be helpful to diversify formulation of herbal medicine, to expand market scale of patent and to develop new application using Korean medicine. In order to establish sufficient data for utilizing patent technologies, more patent studies providing analyzed patent information are needed.

• Food Science and Preservation
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• v.11 no.2
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• pp.195-200
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• 2004

Microbial lethal value and nutrient retention of sous vide processed spinach were evaluated with mathematical model prediction and experimental trial for different package sizes and pasteurization temperatures. The package size covers 500 g, 1 kg and 2 kg, while the pasteurization temperature includes 80, 90 and 97$^{\circ}C$. The basic process scheme consists of filling blanched spinach into barrier plastic film pouch, sealing under vacuum, pasteurization in hot water with over pressure and final cooling to 3$^{\circ}C$. Pasteurization condition was designed based on attainment of 6 decimal inactivation of Listeria monocytogenes at geometric center of the pouch package by heating cycle, which was determined by general method. Heat penetration property of the package and thermal destruction kinetics were combined to estimate the retention of ascorbic acid and chlorophyll. Smaller packages with shorter pasteurization time gave better nutrient retention, physical and chemical qualities. Larger package size was estimated and confirmed experimentally to give higher pasteurization value at center, lower ascorbic acid and chlorophyll contents caused by longer heat process time. Lower pasteurization temperature with longer process time was predicted to give lower pasteurization value at center and lower ascorbic acid, while chlorophyll content was affected little by the temperature. Experimental trial showed better retention of ascorbic acid and chlorophyll for smaller package and higher pasteurization temperature with shorter heating time. The beneficial effect of smaller package and higher pasteurization temperature was also observed in texture, color retention and drip production.