• Title/Summary/Keyword: 냉기

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Changes in Compression Strength of Corrugated Paperboard Box for (콜드체인용 골판지 상자의 냉기공에 따른 압축강도 변화)

  • 김윤호;박형우;김병삼;차환수;홍석인
    • Food Science and Preservation
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    • v.10 no.4
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    • pp.466-469
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    • 2003
  • To develope corrugated paperboard box for cold chain system, it was investigated to compression strength and size of air hole. The size of air holes of the side tested box were designed as six groups, 4, 7, 10% and two kind of air hole, 2, 3 hole per the side. Compression strength of box(440${\times}$330${\times}$170 mm(length${\times}$width${\times}$height))was tested by compression tester UM-20Y, DaeSin Co., Korea, speed is 12.5 mm/min), it was stored 4 week at room temperature, RH 70${\times}$5%. Compression strength was high the mort narrow, the longer of air hole. Compression strength of box of the side, 4% was 10% higher among 4, 7, 10%, but differentiate of compression strength owing to the number of air hole was below 10%. for improving the compression strength of box, paper board box for cold chain system was made of the narrow of width and of the long length of air hole.

Effects of skin temperature change, cold pain and muscle activity by Cold Air Application type on the induced delayed onset muscle soreness (지연성 근육통 유발 후 냉기 적용 방법이 피부온도의 변화, 냉각 통과 근육 기능에 미치는 효과)

  • Choi, Yoorim;Jung, Bongjae;Hwang, Byeongjun
    • Journal of the Korean Society of Radiology
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    • v.7 no.1
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    • pp.99-106
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    • 2013
  • The purpose of this study was to after induced delayed onset muscle soreness, the purpose of this study is to present the effective way on skin temperature changes and cold pain for 14 subjects during to applied with only Cold-jet stream and Cold-jet stream with infra red. 14 healthy men and women who delayed onset muscle soreness eccentric contractions induced by exercise and then the biceps alone was applied to the Cold-jet stream. We measured the time that skin temperature fall from room temperature to $10^{\circ}C$(first period), the time rewarmed from $10^{\circ}C$ to $20^{\circ}C$(second period), the time fall again to $10^{\circ}C$(third period) and the time rewarmed again to $20^{\circ}C$(fourth period). Cold-jet stream with infrared combination therapy was performed with the same method. Results of this study were 1st and 2nd experimental cooling experiments in the to fall to $10^{\circ}C$ Cold-jet stream with infrared combination therapy than in the Cold-jet stream was longer(p<.05). At second period, It took longer in Cold-jet stream with infrared rewarmed than Cold-jet stream to rewarm skin(p<.05). Cold-jet stream with infrared combination therapy than Cold-jet stream had less incidence of cold pain(p<.05). Thickness of biceps brachii were found significant difference related measurment each group was consistent. In this study, Cold-jet stream with infrared combination therapy more effective than Cold-jet stream in reduced cold pain and lowering skin temperature. This work was supported by education capacity building project fund of Taegu Science University, 2012.

Refriferator Temperature Control Using Fuzzy Adaptive Temperature Model (퍼지적응온도모델을 이용한 냉기집중제어)

  • 김지관;이정용;이홍원
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1997.11a
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    • pp.93-97
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    • 1997
  • 본 연구는 새로운 부하(고온의 저장물)가 냉장실 내부에 인입됨에 따라 발생하는 온도불균형을 해소하기 위해 채택된 집중냉각 방식에 있어서의 회전날개의 정지각도 결정 알고리즘 관한 것으로, 특히 냉장실내의 온도에 직접적인 영향을 미치는 압축기 (Compressor) 및 냉기팬(냉기를 냉장실내에 불어넣기 위한 팬)의 운전상황을 입력으로 냉장실내 여러 영역에서의 온도를 추정하는 퍼지적응모델을 이용하여 온도불균형 영역을 검지하고, 이에 따라 회전날개의 각도를 제어함으로서 냉장실 내부의 온도평형을 신속히 이루게하는 특징을 가지고 있다.

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Development of New Model(Dome Type) Cold Storage Facility Using 3-D CFD Simulation (3차원 CFD 시뮬레이션을 이용한 신모델(돔형) 저온저장고 개발)

  • 양길모;고학균;홍지향
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2002.07a
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    • pp.182-187
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    • 2002
  • 국내 저온저장고의 주류를 이루고 있는 컨테이너 박스형 저온저장고의 문제점은 재래식 제어방식으로 인한 성능저하 외에도 자체 구조적인 설계상의 문제점을 가지고 있다 이러한 구조적인 문제점을 열거하면 다음과 같다. 첫째, 한 축 방향에 설치되어있는 유니트 쿨러에서 토출되는 냉기에 의해 저장고 내의 공기를 냉각하는 형태이기 때문에 냉기의 분포가 고르지 못하여 균일한 온도 분포를 이루기 어렵다는 단점을 가지고있다. 둘째, 한 축 방향에서 토출되는 냉기가 맞은 편 벽면까지 도달해야 하기 때문에 풍속이 강해야 하며 이로 인해 저장 청과물이 냉해를 쉽게 입고 심한 증산작용에 의해 쉽게 표면건조나 중량감소를 가져온다. 셋째, 천장부와 측벽부가 90$^{\circ}$의 경사각을 가지고 있어 공기의 유동이 원활하지 못하여 에디현상으로 인한 온도나 풍속의 불균일 구간을 피해서 청과물을 저장해야 하기 때문에 그만큼 버려지는 공간이 많아 비경제적이다. 넷째, 위와 같은 문제점들 때문에 중ㆍ대형의 저온저장고를 컨테이너 박스형으로 설비 할 경우 보다 심한 온도 불균일과 냉기유동 분포를 보여 경제적인 손실이 더 커지게 되는 악순환을 낳게된다. 이에 따라 본 연구에서는 국내 저온저장고의 구조적인 설계상의 문제점을 인식하고 이를 해결하고자 3차원 CFD 시뮬레이션을 이용하여 저온저장고의 새로운 모델을 설계하였다. 이론 바탕으로 직접 저온저장고의 시작기를 개발하여 저장고 내부의 역 유동과 난류유통을 해석하였다. (중략)

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Effect of whole body cryotherapy with spinal decompression on lumbar disc herniation by functional assessment measures (기능적 평가 측정을 통하여 전신냉기치료와 척추 감압기 적용이 요추 추간판 탈출증 환자에게 미치는 효과)

  • Ma, Sang-Yeol
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.6
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    • pp.1101-1108
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    • 2010
  • This study was conducted to investigate whether whole body cryotherapy and spinal decompression have effectiveness on the pain, lumbar flexion range of motion, and global perceived effect scale in patients with lumbar disc herniation. Thirty subjects were participated in this study. And they were all randomly divided into whole body cryotherapy and spinal decompression group. To evaluate the effects of whole body cryotherapy and spinal decompression, subjects were evaluated by using visual analogue scale, lumbar flexion range of motion, and global perceived effect scale. The assessment parameters were evaluated before, after 2 weeks treatments. And we received a consent form whole body cryotherapy subjects. The results of paired t-test, independent t-test, and ANCOVA analysis of variance showed that pain, lumbar flexion range of motion, global perceived effect scale were significantly improved after than before therapy in whole body cryotherapy group. So we conclude that whole body cryotherapy has effectiveness on the pain, lumbar flexion range of motion, and global perceived effect scale in patients with lumbar disc herniation.

Wind Effect on the Distribution of Daily Minimum Temperature Across a Cold Pooling Catchment (냉기호 형성 집수역의 일 최저기온 분포에 미치는 바람효과)

  • Kim, Soo-Ock;Kim, Jin-Hee;Kim, Dae-Jun;Yun, Jin I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.14 no.4
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    • pp.277-282
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    • 2012
  • When wind speed exceeds a certain threshold, daily minimum temperature does not drop as predicted by the geospatial model in a cold pooling catchment. A linear regression equation was derived to explain the warming effect of wind speed on daily minimum temperature by analyzing observations at a low lying location within an enclosed catchment. The equation, Y=2X+0.4 ($R^2$=0.76) where Y stands for the warming ($^{\circ}C$) and X for the mean horizontal wind speed (m/s) at 2m height, was combined to an existing model to predict daily minimum temperature across an enclosed catchment on cold pooling days. The adjusted model was applied to 3 locations submerged in a cold air pool to predict daily minimum temperature on 25 cold pooling days with the input of simulated wind speed at each location. Results showed that bias (mean error) was reduced from -1.33 to -0.37 and estimation error (RMSE) from 1.72 to 1.20, respectively, in comparison with those from the unadjusted model.

An Experimental Study on Heat Flow Characteristics of Inflowing Cool Air in the Room (실내(室內) 유입(流入) 냉기(冷氣)의 열유동(熱流動) 특성(特性)에 관한 실험적(實驗的) 연구(硏究))

  • Jang, Y.G.;Pak, J.W.;Pak, E.T.
    • Solar Energy
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    • v.18 no.1
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    • pp.57-67
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    • 1998
  • A study on a buoyancy effect by the temperature difference between a inner room air and a inflowing cool air and also by Inlet velocity can contribute greatly to enhance performance of air conditioning system, so the study on the distribution characteristics of inflowed cool air is important to analyze the cool air storage in a room. For this study, in the real-sized model room, the temperature differences between inflowing cool air and inner room air are 10, 20, $30^{\circ}C$, and the inlet velocities of inflowing cool air are 1, 2, 3m/s respectively as dynamic parameters. Also, a anemos and a vane type diffuser are used as inlet geometric conditions. Following conclusions have been obtained through this study. 1) In case of the anemos type diffuser, it is found that a dimensionless temperature profile is low and the distribution of the inflowed cool air is uniform. and also, all diffuusers have a low temperature of the inner room as increasing the inlet velocity. 2) A mixing takes place rapidly in case of the anemos type diffuser when the temperature difference is low ${\Delta}T=10^{\circ}C$ and the inletvelocity is high V=3m/s. and the mixing degree is higher with the anemos type diffuser than the vane.

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