• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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• pp.209-213
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• 2008

Recently, it increases in use of CFT(Concrete filled steel tube, below CFT) because material and method are required to be diversification and High-Performance according to increase the super-high structure. But, CFT column lose bearing capacity under fire because steel tube is exposed to outside. As a result, structure is collapsed and then it cause much damage. In case of the Europe, Japan and America, they have studied the fire-resistance performance of CFT under fire for a long time. However, it would have hardly studied it in domestic because it is much difficulty about experiment machine and cost. So it is needed base on fire-resist performance of CFT under fire. Therefore, this study dynamic specificity of stub column which made tester of stub column based on facts of strength and mixing fiber evaluated used heating and load testing machine. As a result, it is willing to propose fundamental data for quick and accurate diagnosis of deteriorated concrete structure by fire damage with experiment according to the design high strength concrete.

• 대한기계학회논문집B
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• 제28권11호
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• pp.1289-1301
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• 2004

Direct numerical simulation (DNS) of strongly-heated air flows moving upward in a vertical tube has been conducted to investigate the effect of gas property variations on turbulence modification. Three heating conditions(q$_1$$^{+}$=0.0045, 0.0035 and 0.0018) are selected to reflect the experiment of Shehata and McEligot (1998) at the inlet bulk Reynolds numbers of 4300 and 6000. At these conditions, the flow inside the heated tube remains turbululent or undergoes a transition to subturbulent or laminarizing flow. Consequently, a significant impairment of heat transfer occurs due to the reduction of flow turbulence. The predictions of integral parameters and mean profiles such as velocity and temperature distributions are in excellent agreement with the experiment. The computed turbulence data indicate that a reduction of flow turbulence occurs mainly due to strong flow acceleration effects for strongly-heated internal gas flows. Thus, buoyancy influences are secondary but not negligible especially for turbulent flow at low heating condition. Digital flow visualization also shows that vortical structures rapidly decay as the heating increases.s.

• 한국농공학회논문집
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• 제58권5호
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• pp.71-79
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• 2016

The effects of spot heating for growing the strawberry cultivated in a plastic greenhouse during the winter that were estimated in Nonsan strawberry experiment station located in Chungnam. The temperature of water for heating was controlled by a electric hot water boiler and kept at the range of $22{\sim}24^{\circ}C$. Heating pipes were set up in root zone for root zone heating and very close to crown for crown heating. Spot heating effects were estimated by applying spot heating system in three test factors of heating root zone, crown only and crown plus root zone. The material for crown heating pipe was white low density polyethylene and the nominal diameter of that pipe was 16 mm. The material for root zone heating pipe was flexible stainless steel and the nominal diameter of that pipe was 15A. The flow rate of heating water circulation was 480 L/h and water circulation lasted for all day long. Temperatures, harvest yield by test beds were surveyed from Nov. 10, 2013 to Apr. 29, 2014. The temperature of crown spot for crown heating bed was at the range of $13.0{\sim}17.0^{\circ}C$ during the night and that of crown spot in control bed was at the range of $8.0{\sim}14.0^{\circ}C$. Also, the temperature of root zone for root zone heating bed was at the range of $18{\sim}21.0^{\circ}C$ and that of root zone in control bed was at the range of $13.0{\sim}15.0^{\circ}C$. The cumulative yield growth rate in earlier harvest period (from Dec. 20 to Mar. 15) of crown heating bed was 43% compared with that of control bed and the cumulative yield of crown plus root zone heating bed was 39 % and that of root zone heating bed was 39 %.

• 한국식품조리과학회지
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• 제1권1호
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• pp.8-17
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• 1985

Followings are the obtained results from the experiment of changes in content of proximate composition, free amino acid and nucleotides in soup prepared from beef brisket, leg bone, tripe and small intestine according to the diverse heating times-3, 6, 12, 18, 24, 30 hrs. The content of moisture in each sample is decreased from 97∼99％ in 8 hours heating to 95∼97% after heating 30 hours. On the contrary, the content of crude protein and crude fat are gradually increased in proportion to the length of heating times and it showed a rapid increasement when it was boiled 6∼12 hours long. We can extract the most protein from the soup stock of tripe among all samples ana the most crude fat from the leg bone. The contents of free amino acids is gradually increased in proportion to the length of heating times. Especially after being boiled longer than 18 hours it is increased obviously. In the soup stock prepared from the brisket, the lysine and alanine were contained the most. In leg bone soup stock, glutamic acid and histidine were extracted the most but bone soup stock, glutamic acid contents were decreased a little in longer heating. In the soup stock of tripe, glutamic acid which is contained very little in a raw material was extracted more as increasing times. In the soup stock of small intestine, lysine and glutamic acid were extracted the most. The least content in free amino acid from each sample was cystine which is sulphur-containing amino acid. These result suggest that, in order to get enough extraction of amino acid, crude fat, 18 hours heating is the most useful while 5’-IMP, which is the taste compound of meat, is extracted at 3 hours heating.

• Elastomers and Composites
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• 제44권4호
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• pp.358-365
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• 2009

고주파 유도가열은 전자기 유도현상을 이용하여 금형표면을 비접촉 형태로 급속 가열할 수 있는 기술이다. 본 연구에서는 고주파 유도가열을 사용하여 사출금형의 표면을 급속으로 가열함으로써 휴대폰 사출성형품의 웰드라인을 제거하기 위한 연구를 수행하였다. 고주파 유도가열 실험을 통해 3초간의 가열로 금형 표면온도를 $143^{\circ}C$까지 가열함으로써 고분자수지의 유리전이온도 이상으로 급속 가열할 수 있음을 확인하였으며, 상기 고주파 유도가열을 적용하여 휴대폰 외장부의 사출성형을 실시하여 기존에 발생되었던 웰드라인을 성공적으로 제거할 수 있었다. 또한 유도가열시 가열조건(고주파 유도가열기 출력 및 가열시간)의 변화에 따른 웰드부 표면특성의 변화를 고찰하였다.

• 한국산학기술학회논문지
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• 제14권9호
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• pp.4197-4203
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• 2013

본 실험연구는 인버터 압축기를 적용한 실내기 3실을 가진 멀티형 열펌프 시스템의 난방운전 시 열펌프의 난방성능을 연구하였다. 멀티형 열펌프의 운전특성은 항온항습 기능을 가진 공기엔탈피방식의 멀티형 칼로리미터를 이용하여 측정되었다. 난방표준 및 난방저온 온도조건에서 실내기 운전조합에 따른 실험을 수행하여 난방성능 변화를 관찰하였다. 실내기 3실을 가진 열펌프의 실내기 운전조합에 따른 난방표준 및 난방저온 운전에서 난방능력, 난방 COP, P-h선도로부터, 3실을 가진 열펌프의 운전특성과 냉매 사이클의 거동을 조사하였다. 열펌프의 운전부하와 성능은 실내기 조합에 의한 부분부하에 의존하므로 열펌프의 난방능력과 사이클의 거동은 다르게 관찰되었다. 표준온도 시험조건 대비 저온 시험조건의 난방능력과 난방 COP는 감소하였다. 또한 실내기 조합에 대한 냉매사이클은 P-h 선도를 사용하여 분석되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1146_1147
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• 2009

This experiment is significant because we can provide information by measuring effect of energy saving for whom plan to install a geothermal heat & cooling system. The result shows geothemal system can save about 50% of energy(heating : 35%, cooling : 60%) and we verified that when using curtain can help saving 4~12% of energy additionally.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 춘계학술대회 논문집
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• pp.399-400
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• 2008

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.365-368
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• 2008

This experiment is significant because we can provide information by measuring effect of energy saving for whom plan to install a geothermal heat & cooling system. The result shows geothemal system can save about 50% of energy(heating : 35%, cooling : 60%) and we verified that when using curtain can help saving $4{\sim}12%$ of energy additionally

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.153-154
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• 2019

This study is a mock-up experiment prior to field application of insulated gang form. In order to investigate concrete Heating cost in winter, pre-comparison was made before application.