• Title/Summary/Keyword: Heating Device

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Unusual Angular Arrangement of Electrodes in Capacitive Heating Device -Thermal Distribution and Clinical Application- (유전 가열장치에서 전극의 각도 배열 -온도 분포의 특성 및 임상 적용-)

  • Seong, Jin-Sil;Chu, Sung-Sil;Kim, Gwi-Eon;John, Juhn-Kyu;Yang, Sung-Wha
    • Radiation Oncology Journal
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    • v.7 no.2
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    • pp.313-320
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    • 1989
  • In capacitive heating device, which considered efficient for deep heating, parallel arrangement of the electrodes is a serious limiting factor in heating for eccentrically located lesions because it causes overheating of the exposed ipsilateral skin surface, the heating pattern is also frequently inappropriate, and the arrangement tends to be unstable due to the patient's gravity. Therefore we attempted an angular arrangement of the electordes to achieve more homogenous and efficient heating for such lesions. In phantom study, both the thermal profile and thermogram established the heating pattern in this unusual angular arrangement of the electrodes at $60^{\circ},\;90^{\circ}\; and\;120^{\circ}$ angles, respectively. An angular arrangement was also clinically applied to 3 patients. The patients' tolerance was good without significant complication and the thermal distribution was satisfactory. In conclusion, this unusual arrangement of electrodes appears to be promising in the clinical application to the eccentrically located lesions.

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A Study on the Warpage of Injection Molded Parts for the rapid Cooling and Heating Device (급속냉각·가열장치에 따른 사출성형품의 휨에 관한 연구)

  • Lee, Min;Kim, Tae-Wan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.8
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    • pp.5074-5081
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    • 2015
  • A method for improving the warpage of the plastic part is a method of removing residual stress of the plastic product. that a non-uniform cooling are appeared in the injection molding process make uniform cooling. this study was developed the Rapid heating and cooling device used peltier module for uniform cooling. Make the Rapid heating and cooling device(RCHD), for Traditional water cooling device(TWCD) method and the Rapid heating and cooling method warpage were compared and were analyzed and the materials used amorphous ABS polymer. various warpage were compared for the process parameters such as packing pressure, packing time, resin temperature, mold temperature, In the amorphous ABS polymer, TWCD method has higher warpage than RCHD method and show the result to be a bit more uniform cooling. The distribution state of the ABS polymer was confirmed Through the Scanning electron microscope. In the TWCD method the distribution state of the polymer be densely distributed, and RCHS method be distributed wider than TWCD method. this is that injection molded parts be seen that cooling was made uniformly, As the temperature of the mold is gradually progress, Particles of the polymer is increased this is that internal stress was reduced.

Structure Optimization of ESD Diodes for Input Protection of CMOS RF ICs

  • Choi, Jin-Young
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.17 no.3
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    • pp.401-410
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    • 2017
  • In this work, we show that the excessive lattice heating problem due to parasitic pnp transistor action in the diode electrostatic discharge (ESD) protection device in the diode input protection circuit, which is favorably used in CMOS RF ICs, can be solved by adopting a symmetrical cathode structure. To explain how the recipe works, we construct an equivalent circuit for input human-body model (HBM) test environment of a CMOS chip equipped with the diode protection circuit, and execute mixed-mode transient simulations utilizing a 2-dimensional device simulator. We attempt an in-depth comparison study by varying device structures to suggest valuable design guidelines in designing the protection diodes connected to the $V_{DD}$ and $V_{SS}$ buses. Even though this work is based on mixed-mode simulations utilizing device and circuit simulators, the analysis given in this work clearly explain the mechanism involved, which cannot be done by measurements.

Development and Thermal Distribution of An RF Capacitive Heating Device (유전가열장치의 개발과 온열분포)

  • Chu, Sung-Sil;Suh, Chang-Ok;Kim, Gwi-Eon;Loh, John-Kyu;Kim, Byung-Soo
    • Radiation Oncology Journal
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    • v.5 no.1
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    • pp.49-58
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    • 1987
  • Hypertermia for the treatment of cancer has been introduced for a long time and the biological effect for the use of hyperthermia to treat malignant tumors has been well established and encouraging clinical results have been obserbed. Unfortunately, however, the engineering or technical aspects of hyperthermia for the deep seated tumors has not been satisfactory. We developed the radiofrequency capactive hyperthermia device (Greenytherm-GY8) in cooperation with Yonsei Cancer Center and Green Cross Medical Corporation. It was composed with $8{\sim}10MHz$ RF generator, capacitive electrode, matching system, cooling system, temperature measuring system and control PC computer. The thermal profile was investigated in agar phantom, animals and in human tumors, heated with capactivie RF device. Deep and homogeneous heating could be achieved in a large phantom of 25cm diameter and 19cm thick when heated with a pair of 23cm diameter electrodes, coupled to both bases of the phantom, when the size of the two electrodes was not the same, the region near the smaller electrode was preferentially heated. It was, therefore, possible to control the depth of heating by choosing proper size of electrodes. Therapeutic temperature $(42^{\circ}C{\sim}43^{\circ}C)$ could be obtained in the living animal experiments. Indications are that deep heating of humn tumors might be achieved with the capacitive method, provided that subcutaenous fat layer is cooled by temperature controlled bolus and large size of electrodes.

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Study on Self-Heating Effects in AlGaN/GaN-on-Si Power Transistors (AlGaN/GaN-on-Si 전력스위칭소자의 자체발열 현상에 관한 연구)

  • Kim, Shin Young;Cha, Ho-Young
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.2
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    • pp.91-97
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    • 2013
  • Self-heating effects during operation of high current AlGaN/GaN power transistors degrade the current-voltage characteristics. In particular, this problem becomes serious when a low thermal conductivity Si substrate is used. In this work, AlGaN/GaN-on-Si devices were fabricated with various channel widths and Si substrate thicknesses in which the structure dependent self-heating effects were investigated by temperature dependent measurements as well as thermal simulation. Accordingly, a device structure that can effectively dissipate the heat was proposed in order to achieve the maximum current in a multi-channel, large area device. Employing via-holes and common electrodes with a 100 ${\mu}m$ Si substrate thickness improved the current level by 75% reducing the channel temperature by 68%.

A Study on Analysis for Energy Demand of the Heating, Cooling and Lighting in Office Building with Transparent Thin-film a-Si BIPV Window (투광형 박막 BIPV 창호 적용에 따른 냉난방 및 조명 부하 저감에 관한 연구)

  • Yoon, Jong-Ho;An, Young-Sub;Park, Jang-Woo;Kim, Bit-Na
    • KIEAE Journal
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    • v.13 no.3
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    • pp.91-96
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    • 2013
  • The purpose of this study was to analyze the annual energy demand including heating, cooling and lighting according to kind of windows with transparent thin-film a-Si Building Integrated Photovoltaic(a-Si BIPV) for office building. The analysis results of the annual energy demand indicated that the a-si BIPV window was reduced by 8.4% than the clear gazing window. The base model A was combinate with a-Si BIPV window area of 67% and clear window area of 33% among the total exterior area. The model B is to be applied with low-e clear glass instead of clear glass of the base model A. The model B was reduced to annual energy demand of 1% more than the model A. Therefore, By using a-si BIPV solar module, the cooling energy demand can be reduced by 53%(3.4MWh) and the heating energy demand can be increase by 58%(2.4MWh) than clear glazing window in office building. Also, Model C applied to the high efficient lighting device to the model B was reduced to annual energy demand of 14.4% more than the Model D applied to the high efficient lighting device to the model A. The Model E applied with daylight dimming control system to the Model C was reduced to annual energy demand of 5.9% more than Model C.

Basic Study on the IoT Micro Boiler (IoT 마이크로 보일러에 대한 기초 연구)

  • Jang, Sung-Cheol
    • Journal of Internet of Things and Convergence
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    • v.8 no.1
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    • pp.23-29
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    • 2022
  • The product to be developed in this study is a heat recovery device which generates steam or hot water at high temperature and high pressure by heating water using exhaust gas from diesel engine, gas engine, gas turbine, etc. as an exhaust gas boiler off heat boiler(EGB) type for ship and power generation. The steam vapor or the created warm water is used as the power source required for the steerage heating and hot water facility or the HFO heating of the ship, and the turbine drive. The principle of waste heat boilers serves to heat water as high temperature exhaust gas with heat pass through the tube of the boiler. The heated water is a structure that is sent to a cabin or turbine device in the form of steam. In this study, the objective of this study is to maximize the efficiency by increasing the heat transfer surface by replacing the tube which is the heat transfer part of EGB with the plate tube.

The Effect of the Heating Conditions on the Warm Hydro-Formability of the Alumium Alloys (알루미늄합금의 열간 액압성형법 성형성에 대한 가열조건의 영향도 분석)

  • Kim, Bong-Joon;Park, Kwang-Su;Ryu, Jong-Soo;Son, Sung-Man;Moon, Young-Hoon
    • Journal of the Korean Society for Heat Treatment
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    • v.18 no.3
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    • pp.172-176
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    • 2005
  • Modern automobiles are built with a steadily increasing variety of materials and semifinished products. The traditional composition of steel sheet and cast iron is being replaced with other materials such as aluminum and magnesium. But low formability of these materials has prevented the application of the automotive components. The formability can be enhanced by conducting the warm hydroforming using induction heating device which can raise the temperature of the specimen very quickly. The specimen applied to the test is A6061, A7075 extruded tubes which belong to the age-hardenable aluminum alloys. But in the case of A6061 age hardening occurs at room temperature or at elevated temperatures before and after the forming process. In this study the effects of the heating condition such as heating time, preset temperature, holding time during die closing and forming time on the hydroformability are analyzed to evaluate the phenomena such as dynamic strain hardening and ageing hardening at high temperatures after the hydroforming process.

Experimental Study on the Heating Performance Improvement of R134a Heat Pump System for Zero Emission Vehicles (무공해자동차용 R134a 히트펌프 시스템의 난방성능 향상에 관한 실험적 연구)

  • Lee, Dae-Woong
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.6
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    • pp.257-262
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    • 2014
  • This paper describes an experimental study for heating performance that can be used in R-134a automobile heat pump systems. The heat pump system is widely studied for heating system in zero-emission vehicles to attain both the small power consumption and the effective heating of the cabin. This paper presents the experimental results of the influence on heating capacity and coefficient of performance of heat pump system. Tests were performed with different sizes of internal and external heat exchangers, and refrigerant flow rate was also considered in two-way flow devices. In addition, the heat, air, and water sources with the heat pump system were examined. The experimental results with the heat pump system were used to analyze the impact on performances. The best combination of performance was A-inside heat exchanger, B-outside heat exchanger, and B-flow device, respectively. In addition, a water heat-source was found to give roughly 40% of better performance than an air heat-source heat pump system.

A Study on the Effect of Envelope Factors on Cooling, Heating and Lighting Energy Consumption in Office Building (사무소 건물의 외피요소가 냉난방 및 조명에너지 소비에 미치는 영향에 관한 연구)

  • Son, Chang-Hee;Yang, In-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.2
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    • pp.8-17
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    • 2012
  • The objective of this study is to perform an analysis of the heat(heating and cooling) and lighting energy consumption according to the window area ratio and the application of horizontal louver, which is external shading device installed for the purpose of energy savings in office buildings. For this, a building was chosen as a typical example, and the heat and lighting energy consumption was calculated by using the daylight and building energy analysis simulation. The results showed that the total energy consumption, when the lighting control was applied, was reduced by an average of 11.49[%] compared to when there was no lighting control. The smaller the glazing ratio is, the less the total energy consumption is. Also, the application of the horizontal louver increases the total energy consumption under the same condition of glazing ratio.