• Korean Journal of Organic Agriculture
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• v.5 no.1
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• pp.101-110
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• 1996

Inorder to minimize the daily intake amount of nitrate by chinese cabbage, the favorate vegetable for Korean, the influences of storage conditions at different temperature and light or dark treatments after post-harvest and effects of cooking temperature and infrared rays on changes of nitrate contents in edible parts of chinese cabbage were determined. The nitrate contents on midrib and leaf blade in chinese cabbage during post-harvest were decreased steeply in 2 days and decreased slowly again in 5 days. The temperature treatment to decrease the nitrate contents in midrib and leaf blade of chinese cabbage were effective as the following of $25^{\circ}C$> $15^{\circ}C$ > $-4^{\circ}C$ > $-10^{\circ}C$. The nitrate contents of midrib and leaf blade were decreased in the timecourse of post-harvest. It is more effective to store in $4^{\circ}C$ than in $15^{\circ}C$, and is more effective in transparent vinyl package than in black vinyl package, but the treatment of light is more effective than the treatment of temperature. The nitrate contents of midrib decreased rapidly by 17.9% in the treatment of 5 days at$ 15^{\circ}C$. By treatment of $80^{\circ}C$, $90^{\circ}C$, $100^{\circ}C$ water, the nitrate contents of midrib were increased slightly, but decreased in leaf blade. It reached 68.5%, 50.6%, 45.9% in the leaf blade respectively by treatment of 80%, 90%, 100% water at 1 min. By infrared rays treatment, the nitrate contents of midrib did not change in 3 min but increased rapidly after 6 min, and in the leaf blade it increased continually after 1 min.

• Journal of Sensor Science and Technology
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• v.30 no.5
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• pp.331-336
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• 2021

The Non-dispersive Infrared (NDIR) gas sensor has high selectivity, measurement reliability, and long lifespan. Thus, even though the NDIR gas sensor is expensive, it is still widely used for carbon dioxide (CO₂) detection. In this study, to reduce the cost of the NDIR CO₂ gas sensor, we proposed the new optical waveguide structure design based on ready-made gas pipes that can improve the sensitivity by increasing the initial light intensity. The new optical waveguide design is a structure in which a part of the optical waveguide filter is inclined to increase the transmittance of the filter, and a parabolic mirror is installed at the rear end of the filter to focus the infrared rays passing through the filter to the detector. In order to examine the output characteristics of the new optical waveguide structure design, optical simulation was performed for two types of IR-source. As a result, the new optical waveguide structure can improve the sensitivity of the NDIR CO₂ gas sensor by making the infrared rays perpendicular to the filter, increasing the filter transmittance.

• Korean Journal of Optics and Photonics
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• v.34 no.3
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• pp.106-116
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• 2023

In this paper, we designed a coaxial dual camera incorporating two optical systems-one for the visible rays and the other for far-infrared ones-with the aim of capturing images in both wavelength ranges. The far-infrared system, which uses an uncooled detector, has a sensor array of 640×480 pixels. The visible ray system has 1,945×1,097 pixels. The coaxial dual optical system was designed using a hot mirror beam splitter to minimize heat transfer caused by infrared rays in the visible ray optical system. The optimization process revealed that the final version of the dual camera system reached more than 90% of the fusion performance between two separate images from dual systems. Multiple rigorous testing processes confirmed that the coaxial dual camera we designed demonstrates meaningful design efficiency and improved image conformity degree compared to existing dual cameras.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.239-245
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• 2000

Sintered $Al_2TiO_5$ has a very low thermal expansion and an infrared radiative selectively emitting large amounts of far infrared rays. However, it is week in mechanical strength. Spectral infrared emittance, thermal expansion coefficient, and mechanical strength of $Al_2TiO_5$-clay composites were studied to develop a material for far infrared radiators. The composites containing 10~50 mass% Jungsan clay had high emittance in the range of 2,000~500cm-1. The bending strength of the $Al_2TiO_5$-clay composites increased with increasing clay content. The $Al_2TiO_5$-clay composites with a clay content of 50mass% and heat-treated at $1,200^{\circ}C$ had a large strength for infrared radiators ; 86MPa. The average linear thermal expansion coefficient from $200{\sim}1,000^{\circ}C$ of the 50mass% jungsan clay containing compo sited heat-treated at $1,200^{\circ}C$ was lower than $3.87{\times}10-6/^{\circ}C$.

• Journal of The Korean Digital Architecture Interior Association
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• v.12 no.1
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• pp.45-51
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• 2012

To see sunlight condition around in storage room, this study analyzers the scope both of sunlight and of the shade of sun into upper and lower window according to seasons. For this, this study investigates sun's seasonal changes, its effect of sunlight and notes antinomic conditions for ventilation and draft performance. In this, Architects of Jangkyunggak tride to block discoloration and fading due to ultraviolet rays and visible rays and block deterioration drying of the surface of Kyung-Pan due to infrared rays by oppressing sunlight flowing by means of narrowing the area of the upper window at front face that has a direct influence of Pan-Ga to avoid the exposure to direct sunlight.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.6
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• pp.21-31
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• 2018

The result of examination of diagnostic method, which is composed of a combination of a thermal camera and a drone that visually shows the temperature of the object by detecting the infrared rays, for detecting the leakage of earth dam was driven in this research. The drone infrared thermography method was suggested to precise safety diagnosis through direct comparing the two method results of electrical resistivity survey and thermal image survey. The important advantage of the thermal leakage detection method was the simplicity of the application, the quickness of the results, and the effectiveness of the work in combination with the existing diagnosis method.

• International journal of advanced smart convergence
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• v.9 no.4
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• pp.203-208
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• 2020

In this paper, we propose the design and implementation of a desktop LED stand and smart app that automatically adjusts color temperature and illuminance for optimal brightness and eye health by improving the structural problem of the LED stand. It is a tabletop LED stand that supports optimal brightness through color temperature control and heat transfer through infrared LED to relieve eye strain through blood circulation and muscle movement. The LED stand works with the smartphone to automatically adjust the optimal brightness and color temperature for the user's environment. In addition, the brightness of the infrared LED is adjusted to a living frequency of 4Hz to relax the eye muscles and reduce eye strain. This study implemented an effective measured data-based system of previous studies through the color temperature and illumination of LED lighting, and near-infrared rays, and presented meaningful results by conducting an experiment to prove the effect through subjects.

• Fire Science and Engineering
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• v.22 no.2
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• pp.91-96
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• 2008

This research studied about the cause analysis of fire that was occurred in far infrared rays heater to base on the fire examples. Fire of electric heater was apt to commit error that handled an over-heating accident by judged molten mark in heat ray. Molten mark which was attached in heat ray was appeared to the form of layer short circuit by other metal material, but other metal material was not found beside the ingredient of heat wire which was mixed to an alloy of Fe-Cr-Al according to result of ingredient distribution by SEM/EDX. Also, the result of overheating experiment by layer short circuit and overvoltage showed higher febrility than normal, but there was no possibility of fire occurrence. This paper will be contributed to science for cause analysis of electric fire through analyzing physical, chemical and flame features of burnout heater on the basis of diagnosis of fire that was happened in infrared rays heater.

• Journal of Conservation Science
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• v.29 no.1
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• pp.35-45
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• 2013

The Clay Statues of Donggwanwangmyo Shrine (Treasure No. 142) are highly damaged physical weathering which are crack, exfoliation. Pigment of surface are discolored by chemical weathering like dust. The result of ultrasonic velocity measurement, low velocity zone was measured the lowest part of Woojanggun Statue. Deficiency condition of pigment layer was evaluated quantitatively through infrared Thermography. As a result, exfoliation part was detected at high temperature. Making techniques of the Clay statues were identified by gamma rays, infrared TV, SEM. All Clay Statues were founded on wood base and joints of wood were fixed using thin iron wires. After wood base was twisted a straw rope, it was made by clay. Clay was blended with rice straw to prevention of crack and exfoliation. The upper side of clay layer was coated with Hanji(Korean handmade paper) and cotton in order to isolate the pigment layer.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.33-34
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• 2012