• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.7
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• pp.975-980
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• 2001

The thermal analysis of the hot roller in a dry film laminator is studied numerically by steady-state two-dimensional heat transfer. In the laminating process for PDP glass or PCB, the temperature distributions in a hot roller are presented considering the effects of the roller rotation speed and the inner and outer radii of the roller. The results show that the temperature distributions are strongly dependent on Peclet number. If Pe number becomes larger, the iso-thermal lines are more concentric about the rotating axis and the temperature difference on the hot roller surface decreases exponentially. It also shows that if the contact angle between the roller and the film becomes smaller the temperature difference becomes smaller. However, the changes of the rollers inner or outer radius have little effect on the temperature difference.

• Journal of Mechanical Science and Technology
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• v.20 no.3
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• pp.382-390
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• 2006

The present study proposes a modified temperature-dependent non-Newtonian viscosity model and investigates the flow characteristics and heat transfer enhancement of the viscoelastic non-Newtonian fluid in a 2:1 rectangular duct. The combined effects of temperature dependent viscosity, buoyancy, and secondary flow caused by the second normal stress difference are considered. Calculated Nusselt numbers by the modified temperature-dependent viscosity model give good agreement with the experimental results. The heat transfer enhancement of viscoelastic fluid in a rectangular duct is highly dependent on the secondary flow caused by the magnitude of second normal stress difference.

• Korean Journal of Optics and Photonics
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• v.4 no.3
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• pp.354-358
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• 1993

The temperature distribution inside a zigzag slab laser glass was measured using a Mach-Zehnder interferometer. The temperature difference between the center and the surface of the slab caused the fracture of the slab glass. Two laser glasses were fractured at a temperature difference ${\Delta}T_0$of TEX>$110^{\circ}C$, $62^{\circ}C$ respectively. For the design of high-average power glass laser, it is recommended that the limit of the temperature difference ${\Delta}T_0$ inside the slab glass should be smaller than $50^{\circ}C$ for safe operation.ration.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.274-277
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• 2003

Critical current(Ic) degradation of HTS tapes after bending is one of the hottest issues in HTS development and application studies. Many people are measuring Ic degradations for effect of bending radius. However even if the bending radius is larger than the breaking radius a HTS tapes can be damaged by repetitive bending, which is unavoidable in the winding processes. Therefore, We studied the Ic degradation after repetitive bending. at 77K with self-field, of Bi-2223 tapes processed by "Powder-in-Tube" technique, which was made by America Superconductor Corporation(AMSC) and superconductiing tapes that strain is imposed measured critical current by temperature difference of L$N_2$ and normal temperature. Like this, critical current could measure that degradation about 1~3％ by temperature difference. These results will amount the most important basis data in power electric machine of superconductivity cable, magnet, etc that winding work is require.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.481-484
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• 2004

A form of measured temperature distribution to estimate condition of a electrical apparatus is a absolute reference for condition of the apparatus, time rate of transition, and difference between reference and currently temperature. Because passive thermography which has not injection of external thermal stimulation shows difference of temperature being on surface of a structure and temperature difference between the structure and back ground, the result could apply only to estimation or monitor for condition of terminal relaxation and overload related with temperature rising. However, a thermal flow in active thermography is differently generated by structure and condition of surface and subsurface. This paper presents the nondestructive testing using the properties and includes the results by heat injection and cooling to the apparatus. The buried discontinuity of subsurface could be detected by these techniques.

• Journal of the Korean Institute of Rural Architecture
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• v.19 no.4
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• pp.57-65
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• 2017

Life quality in farming areas is declining these days on account of decrease in population with the outflow of young generations, advent of aging society, and also lack of social and physical infrastructure. To reverse this, the central and local governments have been devising policies in many ways; however, the vulnerable class in farming area suffering from financial difficulty is not supported with that properly. The results of applying insulation materials applicable to rural houses, EPS, e-board, and glass wool, actually to rural houses are summed as follows. EPS is the most inexpensive among the three installations in terms of material cost and expenses. The indoor and outdoor temperature difference increased from $0.9^{\circ}C$ to $2.5^{\circ}C$, and the temperature change reduced as $0.04^{\circ}C$. With e-board, the indoor and outdoor temperature difference increased from $3.3^{\circ}C$ to $7.5^{\circ}C$; however, the temperature change increased as $0.09^{\circ}C$. Unlike the other two methods, glass wool requires the additional installation of wooden frames. The material cost is highest, and the indoor and outdoor temperature difference increased from $1.1^{\circ}C$ to $8.0^{\circ}C$, and the temperature change reduced as $0.01^{\circ}C$. According to the results of measuring temperature, glass wool's temperature difference is measured to be the highest, but temperature change is found to be the most effective in EPS. Among the three insulation methods, EPS is the most economically advantageous as the material supply is easy and the cost is low. The material is easily processible, so ordinary town residents can install it easily, and it is effective at improving insulation performance, too. But this method cannot be applied when the house has walls that are not even. Also, as the insulator is thick, after the installation, the living space may be narrower as a result.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.6
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• pp.1493-1499
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• 2003

This study was examined for effects of acupuncture of Chok-Samni(ST36) on the facial thermography in health subjects, The volunteers who participating in this study had taken rest for 15 mins in room temperature (19-21 ℃) before the examination and informed them what to prohibit smoking, drinking and administration of drug for the previous day, The thermography of face was taken using Digital Infrared Thermographic Imaging (D.I.T.I. : Dorex, DTI-16UT1, U.S.A.) by time interval of 35 minutes at 15 min before and 20 min after acupuncture stimulation. Thermal temperature of Yangbaek(GB14), Myon-koryo(ST3) and Chichang(ST4) was measured and compared, The results showed that acupuncture of Chok-Samni(ST36) decreased the Absolute difference of temperature between Myon-koryo(ST3) and Chichang(ST4) (p<0,05, Data were represented mean±S,E.M.(n=33)), But, acupuncture of Chok-Samni(ST36) particularly decreased the absolute difference of temperature between Yangbaek(GB14) and Chichang(ST4) and particularly decreased the absolute difference of temperature between Vangbaek(GB14) and Myon-koryo(ST3) (p<0,05, Data were represented mean±S,E.M.(n=33)). Also, it was observed that acupuncture of Chok-Samni(ST36) decreased variety of the color tone of thermographic contour line and decreased thermal distribution. The results showed that acupuncture of Chok-5amni(ST36) significantly decreased the absolute difference of temperature of partial facial surface. Hereafter, study about if acupuncture of Chok-Samni(ST36) significantly decrease the absolute difference of temperature of all the areas of facial surface is requested. Also, continued study of effects of acupuncture of other meridian on the facial thermography is requested.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.2
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• pp.129-138
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• 2010

Technical ceramics, due to their unique physical properties, are excellent candidate materials for engineering applications involving extreme thermal and chemical environments. When ceramics are rapidly cooled, they receive thermal shock. The thermal shock parameter is defined as the critical temperature difference. The critical temperature difference for ceramic parts is influenced by its size, the convective heat transfer coefficient, etc. The thermal shock for a component is analyzed by using the transient thermal stress. If the transient thermal stress exceeds the modulus of rupture (MOR), cracking by thermal shock is initiated. The critical temperature difference for water is less than the critical temperature difference for air. The three-way catalyst substrate used in this study has an adequate performance against thermal shock because its radial and axial temperature differences existed below the critical temperature differences.

• Journal of Veterinary Clinics
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• v.19 no.1
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• pp.37-42
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• 2002

To develop an automatic detecting system of body temperature of dairy cattle while milking, measurement of the temperature of mammary skin using three thermometers attached into the lining of teat cup was carried out for 23 dairy cattle, whereas measurement of the temperature of milk while milking was also performed for 263 animals. For the latter experiment, three thermometers were attached at 10cm(left and right) and 20 cm away from an individual milk collector on the milk transporting hose. Taking the rectal temperature was accompanied all the time for the experiments. The measurement of the temperature of mammary skin using teat cup was successful for 11 of 23 dairy cattle(47.8%) and the mean temperature was $33.5^{\circ}C$ with the mean difference of $5.2^{\circ}C$ from the mean rectal temperature. The measurement of the temperature of milk using the thermometers onto the milk transporting hose while milking was very successful , From 37.3 to $38.4^{\circ}C$ of rectal temperature, the temperature of milk was almost the same and from 38.5 to $39.5^{\circ}C$ of rectal temperature, the temperature of milk tended to be low with the difference of 0.1$^{\circ}C$. From 39.6 to $41^{\circ}C$ of rectal temperature, the temperature of milk tended to be low with the difference of $0.2-0.6^{\circ}C$. These results indicated that automatic detection of body temperature whether low or high can be possible if the temperature of milk is taken while milking and if it is connected to the integration system by on-line.

• Journal of Bio-Environment Control
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• v.23 no.1
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• pp.11-18
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• 2014

To investigate the influence of surrounding environment on the plant temperature and examine the effect of plant temperature control by fogging and airflow, plant temperature of tomato, inside and outside air temperature and relative humidity, solar radiation and wind speed were measured and analyzed under various experimental conditions in plastic greenhouse with two-fluid fogging systems and air circulation fans. According to the analysis of plant temperature and the change of inside and outside air temperature in each condition, inside air temperature and plant temperature were significantly higher than outside air temperature in the control and shading condition. However, in the fogging condition, inside air temperature was lower or slightly higher than outside air temperature. It showed that plant temperature could be kept with the temperature similar to or lower than inside air temperature in fogging and airflow condition. To derive the relationship between surrounding environmental factor and plant temperature, we did multiple regression analysis. The optimum regression equation for the temperature difference between plant and air included solar radiation, wind speed and vapor pressure deficit and RMS error was $0.8^{\circ}C$. To investigate whether the fogging and airflow contribute to reduce high temperature stress of plant, photosynthetic rate of tomato leaf was measured under the experimental conditions. Photosynthetic rate was the highest when using both fogging and airflow, and then fogging, airflow and lastly the control. So, we could assume that fogging and airflow can make better effect of plant temperature control to reduce high temperature stress of plant which can increase photosynthetic rate. It showed that the temperature difference between plant and air was highly affected by surrounding environment. Also, we could estimate plant temperature by measuring the surrounding environment, and use it for environment control to reduce the high temperature stress of plant. In addition, by using fogging and airflow, we can decrease temperature difference between plant and air, increase photosynthetic rate, and make proper environment for plants. We could conclude that both fogging and airflow are effective to reduce the high temperature stress of plant.