• Title/Summary/Keyword: heating elements

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SMA를 이용한 공구홀더의 자동공구교환장치 개발 (Development of Automatic Tool Changer of SMA Tool Holder)

  • 이성철;노승국;박종권
    • 한국생산제조학회지
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    • 제25권1호
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    • pp.1-6
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    • 2016
  • Micromanufacturing is a useful system for reducing energy consumption. For micromanufacturing, tool clamping and workpiece clamping are important components to realize the machining process. Therefore, a shape memory alloy (SMA) ring type tool holder is developed. In addition, this holder needs cooling and heating processes to execute the tool clamping process. This study suggests a cooling/heating device based on peltier elements. The device will be applied to the heating/cooling process of an automatic tool changer (ATC) for the SMA tool holder. This study introduces the configuration and operating principle of the proposed ATC system. The description and prototype evaluation of this system were given. Plastic bolt and aluminum block were selected to enhance the cooling performance, and the installed tool was changed in 17 s during the experiments.

공동주택의 주동 유형별 냉난방부하 분석 (Cooling and Heating Load Analysis According to Building Type of Apartment House)

  • 윤성민;이경희;안영철;김용태
    • 동력기계공학회지
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    • 제18권1호
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    • pp.45-50
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    • 2014
  • This study focuses on the analysis of the cooling and heating load in accordance with apartment houses arrangement type using Ecotect Analysis. Korea have to reduce energy consumption part of building except in industry and transport because the rate of dependence on imports amounts to 94%, Apartment houses built in various forms in order to reduce energy are modelled in each window area ratio, shape, orientation, and climate through simulation. Through this study, we can analyze the cooling and heating load by form, window area ratio, orientation, and climate change and know the optimal elements by the form. In particular, although there have been done research on the window area ratio and the arrangement form, the research of the regional climate characteristics and the direction are hardly carried out. To supplement those problem, adding to seven direction and climatic element of southern region is characteristic(L Type, Y Type, - Type) of this study. The form of apartment houses built 10 years ago is modelled for simulation.

갈색 육수의 이화학적 및 관능적 특성 분석 - 전통 방식과 고압 가열 방식 비교 - (The Analysis of Physicochemical and Sensory Characteristics in Brown Stock - Comparison of Traditional Method and High-Pressure Extracted Method -)

  • 최수근;장혁래;나영아
    • 한국조리학회지
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    • 제14권3호
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    • pp.196-209
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    • 2008
  • This study was conducted to mass-produce brown stock optimized by using a high-pressure heating extractor and to use brown stock as a material for developing various products. For these purposes, we attempted to produce standardized brown stock by extracting brown stock using a high-pressure heating extractor and compared it with brown stock extracted by the traditional method in terms of general elements and mechanical and sensory characteristics. With regard to how to prepare optimal brown stock, the best brown stock was that extracted seven times repeatedly by the traditional method, but the method had a large economic loss in terms of material consumption and took a long time in extraction. Thus, considering time and labor, it was concluded that extraction at 120$^{\circ}C$ for 15 hours using a high-pressure heating extractor is the optimal extraction condition in terms of economic efficiency and quality. The results of this study are expected to be useful as a practical material for making brown stock production process more convenient, applying cooks' traditional cooking techniques to mass production, maintaining standardized superior quality and taste, and improving shelf life.

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마이크로웨이브와 고온발열체를 이용한 연속식 공정의 유류오염토양 처리에 관한 연구 (A Study on Treatment of a Contaminated Soil by Oil using Continuous System of High Temperature Heating Element and Microwave)

  • 하상안;유미영
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제17권1호
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    • pp.8-12
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    • 2012
  • This study is maintains the condition of high temperature (above $600^{\circ}C$) within a short time using on microwave and high temperature heating elements. And removal characteristics according to changes in soil moisture, microwave power and temperature through the decomposition of the contaminated soil by oil. The difficulty resolvability material was sort of lubricating oil having long carbocyclic (C18-C50) and TPH removal rate reached 85.2% at 6 kW and $700^{\circ}C$ and thus the contaminant was removed 1,788 mg/kg within a process time of 40 minutes. In the case of light oil, gasoline contaminated soil, the removal amount showed 567 mg/kg and the treatment rate reached 98.4% at 6 kW, $500^{\circ}C$ and 20 minute. In the case of non-resolvability reached TPH concentrations on 2,000 mg/kg of worrisome level of soil contamination in the 3 zones at 6 kW, $700^{\circ}C$ and 30 minute. At the time, showed up processing costs 8,173 won per ton.

가열시간을 달리하여 제조한 홍합육수의 품질특성 (Quality Characteristics of Mussel Stock with Different Heating Times)

  • 유수현;신경은;최수근;서윤원
    • 한국조리학회지
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    • 제19권3호
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    • pp.209-217
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    • 2013
  • 본 연구에서는 소스나 수프 등의 기본재료가 되는 홍합 육수를 제조함에 있어서 홍합의 각종 영양 성분을 적절하게 이용하여 홍합 육수를 만들고자 하였다. 수분함량은 가열시간이 증가함에 따라 유의적(p < 0.05)으로 낮아졌다. 색도측정 결과, L값은 MS1(35.48)이 가장 높았고, a값도 MS1(-2.39)이 가장 높았으며, b값은 MS5(-9.49)가 가장 높았다. pH는 MS5가 6.56으로 가장 낮아 가열시간이 증가 시 시료 간의 유의적(p < 0.001)인 차이를 보이며 낮아졌다. 당도는 MS3이 $4.03^{\circ}Brix$로 가장 높았고, MS1이 $3.37^{\circ}Brix$로 가장 낮았다. 염도는 MS1이 0.71%로 가장 낮았고, 가열시간이 증가 시 시료간의의 유의적인(p < 0.001) 차이를 보이며 염도가 높아졌다. 홍합육수의 특성차이검사 결과, 육수의 외관, 투명도, 비린냄새, 비린맛, 짠맛은 가열시간 증가 시 강하게 평가되었다. 감칠맛은 MS4가 4.33으로 가장 강하게 평가되었다. 홍합육수의 기호도 검사 결과, 맛, 전체적인 기호도 항목에서는 MS3이 가장 좋게 평가되었다. 이상의 결과로 볼 때, 가열시간 증가로 홍합육수의 기호도가 대체적으로 좋게 평가되었으며, 홍합육수 제조 시 가열시간이 15분일 때 기호도가 상승되는 것을 알 수 있었다.

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콘크리트 폭렬발생 메카니즘에 관한 이론적 고찰 (An Theoretical study on Spalling Mechanism of Concrete)

  • 김형준;김흥열;김경옥
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 2008년도 추계학술논문발표회 논문집
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    • pp.422-427
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    • 2008
  • The major cause of Concrete Spalling at high temperatures can be divided into the Vapor Pressure Rising, caused by the increase in free water temperature within the concrete, and Pore Pressure Rising induced by the vapor moving into dense pores within the concrete. Although the occurrence of spalling within concrete caused by these pressure increases can be assessed experimentally, a close examination into Mechanistic influence against various spalling factors shall be carried out first by using Mathematical Modeling and Theoretical Equations. The Spalling Prospect Process by theoretical mechanism is expedited in order of the following; selection of heating condition (fire strength and flame heating direction), a selection of constituent elements, an analysis of heat transmission, an analysis of moisture movement, distribution of water content, an analysis of pore/vapor pressure, and assessment of spalling occurrence.

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대형 하이브리드 트럭용 열전 무시동 공조시스템 성능 연구 (Performance of Non-starting Conditioning System using Thermoelectric Modules for Hybrid Heavy Trucks)

  • 박경민
    • Tribology and Lubricants
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    • 제29권5호
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    • pp.310-317
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    • 2013
  • To reduce vehicle fuel consumption due to not only driving but also air conditioning, battery-operated non-starting conditioning systems with thermoelectric modules and without mechanical elements like compressors are being manufactured for use by hybrid heavy trucks in the near future. In this study, the voltage and current consumed by a thermoelectric module were measured to determine the required battery power, and the performance of the conditioning system with air temperature, and humidity of the inlet/outlet modules and inside/outside the cabin for a truck, was evaluated using experimental apparatus under actual conditions. The results showed that, the thermoelectric module can be continously operated for about 1.5 h using existing 24 V batteries. The coefficent of performance(COP) of the cooling and heating modes was calculated to be an average 0.8-1.32. As expected, the heating performance was 30% more efficient than the cooling performance, which is general characteristic of thermoelectric modules.

김해에서 관측한 접지역전층의 특성에 관한 연구 (A Study on the Characteristics of Inversion Layer Observed at Kimhae)

  • 박종길;원경미
    • 한국환경과학회지
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    • 제3권4호
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    • pp.305-315
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    • 1994
  • The field observation was carried out to investigate the characteristics of surface inversion layer at Kimhae using the feild observed date and upper layer meteorological data during 4-5 February 1993. The results of the study can be summarized as follows : The maximum height of surface inversion layer observed at Kimhae is 193m and the height of upper level inversion layer ranges from 2nm to 300m. The surface weather elements was influenced the formation of surface inversion layer. According to the pasquill stability and time variation of temperature with height, both the surface heating from insolation and the disturbance of upper level of inversion layer was influenced the disappearance of inversion layer. And the stability of surface temperature inversion layer generally belongs to the class of F, that of upper level temperature inversion layer commonly to the class of E.

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급속 금형가열에 의한 박육 사출성형의 유동특성 개선에 관한 연구 (A Study on Improvement of Flow Characteristics for Thin-Wall Injection Molding by Rapid Mold Heating)

  • 박근;김병훈
    • 소성∙가공
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    • 제15권1호
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    • pp.15-20
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    • 2006
  • The rapid thermal response (RTR) molding is a novel process developed to raise the temperature of mold surface rapidly to the polymer melt temperature prior to the injection stage and then cool rapidly to the ejection temperature. The resulting filling process is achieved inside a hot mold cavity by prohibiting formation of frozen layer so as to enable thin wall injection molding without filling difficulty. The present work covers flow simulation of thin wall injection molding using the RTR molding process. In order to take into account the effects of thermal boundary conditions of the RTR mold, coupled analysis with transient heat transfer simulation is suggested and compared with conventional isothermal analysis. The proposed coupled simulation approach based on solid elements provides reliable thin wall flow estimation for both the conventional molding and the RTR molding processes.

AZ31 Mg 합금의 고온 변형 시의 동적 연화 현상 (Flow Softening Behavior during the High Temperature Deformation of AZ31 Mg alloy)

  • 이병호;;염종택;이종수
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2006년도 춘계학술대회 논문집
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    • pp.70-73
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    • 2006
  • In the present study, the flow-softening behavior occurring during high temperature deformation of AZ31 Mg alloy was investigated. Flow softening of AZ31 Mg alloy was attributed to (1) thermal softening by deformation heating and (2) microstructural softening by dynamic recrystallization. Artificial neural networks method was used to derive the accurate amounts of thermal softening by deformation heating. A series of mechanical tests (High temperature compression and load relaxation tests) was conducted at various temperatures ($250^{\circ}C{\sim}500^{\circ}C$) and strain rates ($10^{-4}/s{\sim}100/s$) to formulate the recrystallization kinetics and grain size relation. The effect of DRX kinetics on microstructure evolution (fraction of recrystallization) was evaluated by the unified SRX/DRX (static recrystallization/dynamic recrystallization) approaches

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