• 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.

• KIEAE Journal
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• v.13 no.3
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• pp.61-69
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• 2013

The experiment on thermal characteristics of on-dol systems were carried out to apply to New Han-ok's heating system. Change of surface temperature varied with heating times, distribution of surface temperature, radiation property were surveid on four on-dol system in laboratory conditions. Followings are results. 1) "Hwang-to unit" was most favorable condition of the distribution of floor surface temperature. And the results from reaching time to thermal comfort temperature of on-dol system showed that "Hwang-to unit" was the most favorable to continuance of floor temperature. 2) There were a little difference in surface floor radiations of $30^{\circ}C$ for three wet on dol-systems. 3) It was suggested that "Hwang-to unit" is the most appropriate to floor heating system of new han-ok considering eco-friendship and continuance of floor temperature in intermittent heating condition.

• Journal of Welding and Joining
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• v.25 no.4
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• pp.58-64
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• 2007

Recently, the electro-magnetic induction process has been utilizing to substitute the flame heating process in shipyard. However, few studies have been performed to exactly analyze the deformation mechanism of the heating process with mathematical model. This is mainly due to the difficulty of modeling the inductor travelling on plate during the process. In this study, heat flux distribution of the process is firstly numerically analysed with the assumption that the process has a quasi-stationary state and also with the consideration that the heat source itself highly depends on the temperature of base plate. With the heat flux, the thermal and deformation analyses are then performed with a commercial program for 34 combinations of heating parameters. The deformations obtained and heating parameters are synthesized with a statistical method to produce simplified formulas, which easily give the relation between the heating parameters and deformations. The formulas are well compared with results of experiment.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.5
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• pp.419-425
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• 2016

A powder spreading phenomenon is one of disadvantageous characteristics of the powder bed fusion process using electron beams. The powder spreading phenomenon can be controlled using a pre-heating process of metallic powders. The aim of this paper was to investigate the preheating process of Stellite21 powder using electron beams. Powder spreading experiments were performed to examine the influence of process parameters on the spreading behaviors of Stellite21 powder. Powder heating experiments were carried to investigate the effects of the focusing current of the electron beam on the quality of the heated region. Using the results of the powder spreading and heating experiments, an appropriate combination of process parameters was obtained. The pre-heating experiment of Stellite21 was performed using the estimated combination of process parameters. The results of preheating experiments showed that the preheated Stelllite21 layer with desired characteristics can be created when the estimated combination of process parameters is applied.

• Journal of Institute of Convergence Technology
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• v.6 no.1
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• pp.7-11
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• 2016

An experiment was performed to show the bio-signal characteristics of the Stuckyi when was heated. To measure the bio-signal of the plant, this study used the electrode with copper(+) and constantan(-). The electrode was directly inserted into the Stuckyi stems. And used T-type thermocouple to measure the inside temperature of the Stuckyi. During the experiments, room temperature also measured with T-type thermocouple. Heating was made with hair dryer periodically that 3 times turned on for heating 5 min and off for non-heating 25 min. Under the situation, the responses of the Stuckyi including voltage potential and inside temperature were measured using data logger(HP-34970A) according to the distances(15cm, 30cm, 45cm) between hair dryer and the plant. Through the experiments, We knew that the inside temperature has similar level and behavior with the room temperature at normal state. And during heating period, the inside temperature and the potential were also simultaneously increased sharply. From the experiments, we revealed that the measuring system of bio-signal of the plant being proposed in this study can be useful to show the Characteristics of the plants.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.8
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• pp.375-380
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• 2014

The purpose of this paper is to investigate the cooling and heating performance of a standalone-type thermoelectric system equipped with a thermoelectric module. The system consists of a blower and two thermoelectric modules with a fin, which is soldered onto both sides of the thermoelectric module and a courtesy light. The thermoelectric system experiment is conducted with the intake voltage to find the optimum cooling and heating performance of each. The results showed that the cooling capacity and coefficient of performance (COP) were 22 W and 0.31, and the heating capacity and COP were 147 W and 1.1, respectively. In the vehicle cooling and heating performance test in a climate wind tunnel, the results showed that the standalone thermoelectric system's cooling performance was slightly better than the base system; and the heating performance of the standalone thermoelectric system was $54.1^{\circ}C$ and the COP was 1.3, compared to the base system.

• The Journal of Internal Korean Medicine
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• v.35 no.1
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• pp.59-69
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• 2014

Objectives : This study was designed to test the effect of heating condition and Panax ginseng on body temperature, hematologicala changes, and immune response. Methods : The extract from Panax ginseng was made by the pharmacy department of Kyung Hee Oriental Medical Hospital. The animals were divided into four groups; control, room temperature Panax ginseng (G), $28^{\circ}C$ heating, and $28^{\circ}C$ heating Panax ginseng (heating G). Each group has 8 Sprague-Dawley rats. We measured body weight & temperature twice a week. After 2 weeks of experiment, serum lipid level, WBC, differential count, lymphocyte proliferation and immune cytokine concentration were measured. Results : 1. Simultaneous application of heating condition and Panax ginseng induced decreased body weight and increased body temperature. 2. Simultaneous application of heating condition and Panax ginseng induced decreased AST, ALT and BUN. 3. Simultaneous application of heating condition and Panax ginseng tended to decrease TNF-${\alpha}$ concentration, while application of room temperature and Panax ginseng tended to increase TNF-${\alpha}$ concentration. Conclusions : Simultaneous application of heating condition and Panax ginseng decreseas body weight, increases, body temperature and has a tendency to decrease TNF-${\alpha}$ concentration.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.3
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• pp.655-663
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• 2024

In order to meet the technological demand for indoor heating systems that ensure winter thermal comfort during the transition from internal combustion engines to electrification, a localized proximity heating module using surface heating elements was developed. The operational performance of heating module was tested in the low temperature chamber. The experiment conditions were varied by changing the chamber temperature (-10, 0℃), the air flow rate (6.2, 6.0, 4.2m³/h), the heater power (100, 80, 60, 40W). Thermal comfort model was confirmed using the CBE Thermal Comfort Tool applying ASHRAE standard 55. Under -10℃ condition, thermal comfort was satisfied at 23.4, 23.2℃ at power of 100W and air flow rate 6.0, 4.6m³/h. Under 0℃ condition, at power of 80W, air flow rate 6.2, 6.0m³/h, and at power of 60W, air flow rate 4.6m³/h showed results of 25.7, 26.1, 23.0℃, respectively, satisfying thermal comfort. This study analyzed the operating performance of the local proximity heating module in the low temperature chamber and applied thermal comfort model to prove applicability of local proximity heating module using surface heating elements and how to utilize the thermal comfort model.

• Korean Journal of Environmental Agriculture
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• v.2 no.2
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• pp.114-119
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• 1983

Several supplementary heating methods were investigated to find their effects on night air temperature, injury in plant, growth and yield with Hokowase strawberry(Fragaria grandiflora) under greenhouse, during early spring season in 1981 and 1982. Kerosene lamp as a supplementary heating was not suitable because of its severe injury on strawberry plants, danger of accidental fire and bad smell. Paraffine candle and electric wire heating did not injure on strawberry plant, raised the minimum air temperature in greenhouse at night, enhanced growth, flowering and harvesting time of strawberry. Paraffine candle was effective as a supplementary heating method for short period growing under greenhouse, whereas electric wire heating was suitable for long period cultivation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.4
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• pp.72-80
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• 2009

The main purpose of this study is as follows : Finding a solution for fresh wood chips to be used as an alternative growing-media through a study of the formation method of a compost base that is applicable on both construction site and composting factory to ferment fresh wood chips produced from construction site as well as a study on adjuvant or secondary materials. The result from the experiment plot using wood chips sized 50mm or less, manure and fertilizer mixed manure as a source of nitrogen to compost fresh wood chips has shown that the temperatures 9days and 3days after the beginning of the experiment reached to $49.0^{\circ}C$ and $40.4^{\circ}C$ respectively, the heating duration was 7days and 4days respectively, and the C/N ratio was 26.5 and 25.3, each satisfying the standard for composted manure (25.0~40.0). Also, the other result from another experiment plot using mixture of sandy soil and microorganism as an inoculation source of microorganism has shown that the temperature 10days after the beginning of the experiment reached to $67.6^{\circ}C$ and lasted 16days. The experiment plot using sandy soil has shown the highest figure of $5.3{\sim}108$ CFU/g in terms of number of microorganism. The result from the experiment plots for on-site composting of fresh wood chips have shown that the experiment plot that used sandy soil with fertilizer due to supply restriction of manure as a nitrogen source in construction site reached the high temperature of $54.7^{\circ}C$ after 3days of experiment beginning and maintained heating state for 17days and reached 30.6 of C/N ratio, satisfying the standard for composted manure.