• The Transactions of the Korean Institute of Electrical Engineers P
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• v.56 no.3
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• pp.142-147
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• 2007

Infrared thermography is one of the most valuable and cost-effective diagnostic techniques for predictive maintenance on electrical systems. For the electric installations, the thermographies can identify major problems, which if left unattended could lead to breakdowns. The result thermal images depend upon operator skills, inspection technique, and load and weather conditions. When the thermographer is applied to remote monitoring, the conditions of the systems are not perfectly analyzed because operators are hard to know the weather's effects of the installed place. Therefore, this paper defines the effects by weather conditions which will influence the final results. The purpose of this paper is to define the weather effects that a thermographer needs to consider for successful condition analysis.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1991.10a
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• pp.18-22
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• 1991

Far Infrared radiators should have functionality to convert thermal energy into electron wave. In order to apply the Far Infrared to the substance, the absorption characteristics of the substance should be considered. In this paper, interrelation of emissivity with emission energy according to temperature in the range of 2.5$\mu$m to 25$\mu$m after the transition element oxides (MnO2, Fe2O3, CuO, Co3O4) of first grade reagent were molded in press, then they were calcinated in 1050˚C, and they were used as samples.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.9 no.6
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• pp.32-40
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• 1995

Far Infrared radiators should have functionality to convert thermal energy into an electromagnetic wave. In order to apply the Far Infrared to the substance, the absorption characteristics of the substance should be considered. In this paper, interrelation of emissivity with emission energy according to temperature in the range of [$2.5\mu\textrm{m}$] to 25[$\mu\textrm{m}$] after the transition element oxides (MnO2, Fe2O3, CuO, Co3O4) of first grade reagent were molded in press, then they were sintered in [$1050^{\circ}C$], and they were used as samples.

• Journal of Mechanical Science and Technology
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• v.19 no.10
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• pp.1950-1956
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• 2005

An analysis has been carried out to investigate the effect of the reflectivity on the temperature distribution of a glass panel by infrared radiant heating. Halogen lamps are used to heat the panel, located near the top and bottom of the rectangular chamber. The thermal energy is transferred from the lamps to the panel only by radiation and it is considered by using view factor. The conductive transfer is limited inside the panel. The results show that the uniformity of the temperature distribution of the panel is improved and, at the same time, the time for heating increases as the wall reflectivity increases. The temperature difference between the center and the corner reaches a maximum in the early stage of the heating process and then decreases until it reaches a uniform steady-state value.

• Journal of Korea Multimedia Society
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• v.17 no.11
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• pp.1270-1278
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• 2014

The modern infrared (IR) imaging systems use mainly one or more wavelength bands among short wavelength IR (SWIR), middle wavelength IR (MWIR), and long wavelength IR (LWIR) bands. In the process of IR image synthesis and modeling, IR image wavelength-band conversion which transforms arbitrary band image to other band one is required. The wavelength-band conversion procedure includes a temperature estimation process of an object surface. However, in this procedure, an approximated Planck's radiation equation causes errors in estimated temperature. In this paper, we propose an estimation temperature error attenuation method in IR image band conversion procedure. The estimated temperature is corrected with a slope information of radiance according to it. The corrected temperature is used for generation of the other band IR image. The verification of proposed method is demonstrated through the simulation.

• Journal of Astronomy and Space Sciences
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• v.9 no.2
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• pp.183-192
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• 1992

We have investigated the properties of dust grains in the envelopes of infrared carbon stars by testing various radiative transfer model spectra with different stellar and enveloped parameters. We have deduced a new opacity pattern for the dust grains reflecting both the experimental data and the model fitting with recent infrared observations. The best pattern we find is very similar to amorphous carbon with a slight modification that could be attributed to some unknown dust grain materials. Unlike oxygen-rich dust grains, the optical properties of carbon grains do not show any reasonable tendency of temperature dependence. We find that the Planck mean values of radiation pressure efficiency factors for the modified amorphous carbon are much larger than those for graphite.

• Journal of the Korean Society for Nondestructive Testing
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• v.14 no.4
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• pp.244-249
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• 1995

Infrared(IR) thermography method was developed as a result of an investigation into a means of deriving a more visual method of temperature analysis. It recently provides an excellant nondestructive testing(NDT) technique in a variety of industries such as nuclear power plant, fossil plants, etc.. This paper offers a basic principles of infrared radiation, the nature of instruments used for measurement and the applications.

• Journal of The Korean Astronomical Society
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• v.43 no.6
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• pp.213-223
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• 2010

Young Stellar Objects (YSOs) in the early evolutionary stages are very embedded, and thus they emit most of their energy at long wavelengths such as far-infrared (FIR) and submillimeter (Submm). Therefore, the FIR observational data are very important to classify the accurate evolutionary stages of these embedded YSOs, and to better constrain their physical parameters in the dust continuum modeling. We selected 28 YSOs, which were detected in the AKARI Far-Infrared Surveyor (FIS), from the Spitzer c2d legacy YSO catalogs to test the effect of FIR fluxes on the classification of their evolutionary stages and on the constraining of envelope properties, internal luminosity, and UV strength of the Interstellar Radiation Field (ISRF). According to our test, one can mis-classify the evolutionary stages of YSOs, especially the very embedded ones if the FIR fluxes are not included. In addition, the total amount of heating of YSOs can be underestimated without the FIR observational data.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.08a
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• pp.27-30
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• 2003

In order to get the infrared ray radiator with high efficiency emission, the starting raw material $Fe_2O_3$ powder is heat-treated under the oxygen pressure log[$PO_2$] = -13~15 at $800^{\circ}C$ for 2hours. It has shown that the radiation rate was larger than 0.85 at the relatively high temperature($400^{\circ}C$), and decreased slowly with increasing the temperature from 50 to $400^{\circ}C$.

• Journal of Sensor Science and Technology
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• v.29 no.6
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• pp.433-439
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• 2020

Recently, the need for IoT-based intelligent systems is increasing in various fields. In this study, we implemented the system that automatically measures the sugar content of fruits without damage to fruit's marketability using near-infrared radiation and machine learning. The spectrums were measured several times by passing a broadband near-infrared light through a fruit, and the average value for them was used as the input raw data of the machine-learned DNN(Deep Neural Network). Using this system, he sugar content value of fruits could be predicted within 5 s, and the prediction accuracy was about 93.86%. The proposed non-destructive sugar content measurement system can predict a relatively accurate sugar content value within a short period of time, so it is considered to have sufficient potential for practical use.