• Proceedings of the KWS Conference
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• 2003.05a
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• pp.111-113
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• 2003

The existing heating unit is indirect-heating method that make use or the nichrome wire or halogen lamp. The indirect-heating method has the demerits of long warming time, high power consumption and many organization parts. In this study, the heating unit of direct-heating method manufactured as being the thermal spray coating of conductive heating material on the surface of heating unit in order to improve the demerits of indirect-heating method. And YSZ added Ni-20Cr that had moderate electrical resistivity was chosen of the conductive heating material.

• Journal of Acupuncture Research
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• v.21 no.4
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• pp.31-51
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• 2004

Objective: The propose of this study is to investigate the characteristics of combustion in indirect moxibustion with garlic. Methods: We observed the characteristics of combustion by the variations of the thickness(3mm, 4mm, 5mm) of a slice for indirect moxibustion with garlic and mass(80mg, 100mg, 120mg) of moxa cone and existence of holes. The temperature of indirect moxibustion for garlic insulation with holes was higher than temperature of indirect moxibustion for garlic insulation without holes. Combustions time in the preheating period is about 1 minute, it varies by the existence of holes, the thickness of a slice for indirect moxibustion with garlic, and the density of moxa cone. Results: Maximum temperature of heating period was $38.7{\sim}46.2^{\circ}C$, combustion time in the heating period was 118~164sec and maximum ascending temperature gradient was $0.102{\sim}0.264^{\circ}C/sec$. Retaining period was shorter than heating period and stimulus of heating retains more, because it is higher than body temperature. By this report, indirect moxibustion with garlic is more effective with holes and the appropriate thickness of a slice for indirect moxibustion with garlic is 3.5~4mm. It is appropriate that the diameter of moxa cone is 8mm and height of that is 10mm. With this condition, effective combustion period is 120sec, maximum temperature is $42{\sim}44^{\circ}C$, maximum ascending temperature gradient is $0.14{\sim}0.16^{\circ}C/sec$. It is necessary to study clinical correlations for more accurate quantitative standard.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.6
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• pp.288-291
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• 2002

We developed a new RF indirect-heating LPE furnace. The thermal gradient of our newly developed furnace is less than that of direct heating, and is as gentle as that of the resistance-heating LPE furnace. With this new furnace, the heating and/or cooling is faster than that of the resistance-heating furnace. Impurity-doped YIG film was grown from a $PbO-B_{2}O_{3}$, based flux on a (111) GGG substrate. To study the effect of the impurities on the MSSW threshold power and the saturation response time, we used two microstrip lines to excite and propagate the MSSW at 1.9 GHz. The MSSW threshold power and saturation response time was found to be related to the $\Delta$H.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.1
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• pp.37-42
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• 2009

This paper describes the fuel oil characteristics of mulching waste vinyl by indirect heating emulsion system. For the emulsion experiment of waste vinyl, the system is composed of melting furnace, the 1th pyrolysis furnace, and the 2nd pyrolysis furnace. The mulching waste vinyl is used for the fuel oil characteristics analysis of mulching waste vinyl. The refined oil, gasoline, and diesel oil are extracted and quantified to analysis the fuel oil characteristics. From the results of experiments, it has been shown that the production of fuel oil from mulching waste vinyl is possible using the emulsion system.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.69-74
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• 2001

In this Paper are described the indirect induction heated boiler and induction heated hot air producer using the voltage-fed series resonant high-frequency inverter which can operate in the frequency range from 20kHz to 50kHz. A specially designed induction heater, which is composed of laminated stainless assembly with many tiny holes and interconnected spot welding points between stainless plates, is inserted into the ceramic type vessel with external working coil. This working coil is connected to the inverter and turbulence fluid through this induction heater to moving fluid generates in the vessel. The operating performances of this unique appliance in next generation and its effectiveness are evaluated and discussed from a practical point of view.

• Journal of Korean Society of Water and Wastewater
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• v.38 no.3
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• pp.155-164
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• 2024

There are two primary sludge drying methods such as the direct heating microwave method and the indirect heating steam one. In this study, the drying treatment facility at sewage treatment plant A applied both of these drying methods. The research aimed to investigate the optimal operation approach for the drying facility, considering the input sludge and the moisture content data after the drying process. Moisture content and removal rate data were executed at the research facility from January 2016 to December 2018. First, the microwave, a direct heating drying method, performed intensive drying only on the outer surface of the sludge by directly applying heat to the sludge using far infrared rays, so effective sludge drying was not achieved. On the other hand, the steam method of the indirect heating method used steam from a gas boiler to maximize the utilization of the heat transfer area and reduce energy of the dryer, resulting in an effective sludge drying efficiency. The sludge moisture content brought into the sludge drying facility was about 80%, but the moisture content of the sludge that went through the drying facility was less than 10% of the design standard. Therefore, the steam method of the indirect heating method is more effective than the microwave method of the previous direct heating method and is more effective for maintenance It has proven that it is an efficient method of operating construction facilities.

• Journal of Acupuncture Research
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• v.27 no.3
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• pp.35-45
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• 2010

Backgrounds : Recently, commercial indirect moxibustion has been widely used as a substitute for traditional indirect moxibustion by clinicians due to its convenience in using. But, there has been lack of studies about the similarity of thermal stimulation between commercial indirect moxibustion and traditional indirect moxibustion. Objectives : To demonstrate commercial indirect moxibustion can substitute for traditional indirect moxibustion by comparing thermal stimulation between the two. Methods : We measured bottom temperature of commercial indirect moxibustion and traditional indirect moxibustion with various thicknesses of ginger and garlic. A clinical trial was performed on 18 healthy subjects to evaluate thermal stimualtion. The subjects were randomly assigned into two groups, traditional indirect moxibustion with ginger and garlic. The skin temperature and heating time were measured. They received moxibustion therapy with commercial indirect moxibustion and traditional indirect moxibustion according to their groups. Acupoint Chogcoe($LU_6$), Zusanli($ST_{36}$) and Tianshu($ST_{25}$) were used in each group for 3 times. Results : There was no difference in bottom temperature among commercial indirect moxibustion, traditional indirect moxibustion with 2mm ginger and 3mm garlic. No major difference was detected in the subjects' baseline data. There was no difference in skin temperature and heating time among these 3 type of moxibustions. Also, No major difference was detected in VAS score of thermal stimulation and frequency of burns among these 3 type of moxibustions. But, most subjects regarded their sensation weren't identical because of its own distinct characteristics. Conclusions : Commercial indirect moxibustion, traditional indirect moxibustion with 2mm ginger and 3mm garlic have same thermal stimulation. Thus, commercial indirect moxibustion can substitute for traditional indirect moxibustion.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.5
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• pp.594-600
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• 2007

Rapid mold heating has been recent issue to enable the injection molding of thin-walled parts or micro/nano structures. Induction heating is an efficient way to heat a conductive workpiece by means of high-frequency electric current caused by electromagnetic induction. Because the induction heating is a convenient and efficient way of indirect heating, it has various applications such as heat treatment, brazing, welding, melting, and mold heating. The present study covers an experimental investigation on the rapid heating using the induction heating and rapid cooling using a vortex tube in order to eliminate an excessive cycle time increase. Experiments are performed in the case of a steel cup mold core with various heating and cooling conditions. Temperature is measured during heating and cooling time, from which appropriate mold heating and cooling conditions can be obtained.

• New & Renewable Energy
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• v.17 no.2
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• pp.40-49
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• 2021

This paper explains the development process of methane decomposition to hydrogen and carbon black using solar thermal energy. It also demonstrates the advantages and disadvantages of five different reactors for each development stage, including the reactor's experimental results. Starting with the initial direct heating type reactor, the indirect heating type reactor was developed through five modifications. The 40-kWth solar furnace installed at the Korea Institute of Energy Research was used for the experiment. In the experiment using the developed indirect heating reactor, an 89.0% methane to hydrogen conversion rate was achieved at a methane flow rate of 40 L/min, obtained at about twice the flow rate compared to previous advanced studies.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.1
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• pp.48-54
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• 2002

This paper is described the indirect induction heated boiler and induction heated hot air producer using the voltage-fed series resonant high-frequency inverter which can operate in the frequency range from 20 kHz to 50 kHz. A specially designed induction heater is composed of laminated stainless plates, which have many tiny holes and are interconnected by spot welding. This heater is inserted into the ceramic type vessel with external working coil. This working coil is connected to the inverter and turbulence fluid through this induction heater to moving fluid generates in the vessel. The operating performances of this unique appliance in next generation and its effectiveness are evaluated and discussed from a practical point of view.