• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.6
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• pp.111-117
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• 2002

The high quality and a nearly stoichometric growth of $Cd_{1-y} Zn_y$/Te(y＝0.04) epilayers have been successfully grown on GaAs substrate by hot wall epitaxy (HWE) by optimizing the growth condition including the preheating treatment and Cd reservoir temperature. The relationship between quality and thickness was examined and best value of FWHM from X-ray rocking curve of 121 arcsec are obtained. Also, emission peaks related to the recombination of free excitons such as the ground state and the first excited state were observed in the PL spectrum at 4.2K. The ($A^0$, X) emission related to Cd vacancy and deep level emission was not measured. These results indicated that the grown CZT/GaAs epilayer was high qualify and purity.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.28.4-28
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• 2001

This paper proposes an IR camera system that performs the task of removing mines for humanitarian purposes. Because of the high risks involved, it is necessary to conduct mine detection from the most remote endeavoring. By mating use of infrared ray (IR) cameras, scattered mines can be detected from remote locations. In the case of mines buried in the ground, detection is possible if the peripheral temperature difference is large enough between the ground and mine weapon. As one of the world´s advanced nations in sensor technology, Japan should promote surveys and studies for detecting mines safely by using its advanced remote sensing technologies.

• Journal of Aerospace System Engineering
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• v.14 no.6
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• pp.79-84
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• 2020

Cooler driver electronics (CDE) for maintaining low temperature of the satellite payload IR sensor consists of a compressor that has a pulsation current load condition when it is operated. This pulsation current produces large voltage fluctuation, which affects both load and regulated bus stability. Thus, CDE power conditioning system consists of a primary bus, infrared power distribution unit for battery charging and protection, reverse current protection diode, and battery, which is used as a buffer. In this study, the operational mode analysis is performed by each part with equivalent impedance modeling verified through system level simulation. From this mode analysis, the safety margin for state of charge and open circuit voltage of the battery is determined for satisfying the minimum operational voltage of the CDE load.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.4
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• pp.223-233
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• 2021

Systematic and continuous monitoring and management of the energy consumption of buildings are important for estimating building energy efficiency, and ultimately aim to cope with climate change and establish effective policies for environment, and energy supply and demand policies. Globally, buildings consume 36% of total energy and account for 39% of carbon dioxide emissions. The purpose of this study is to generate three-dimensional thermo-spatial building models with photogrammetric technique using drone TIR (Thermal Infrared) images to measure the temperature emitted from a building, that is essential for the building energy rating system. The aerial triangulation was performed with both optical and TIR images taken from the sensor mounted on the drone, and the accuracy of the models was analyzed. In addition, the thermo-spatial models of temperature distribution of the buildings in three-dimension were visualized. Although shape of the objects 3D building modeling is relatively inaccurate as the spatial and radiometric resolution of the TIR images are lower than that of optical images, TIR imagery could be used effectively to measure the thermal energy of the buildings based on spatial information. This paper could be meaningful to present extension of photogrammetry to various application. The energy consumption could be quantitatively estimated using the temperature emitted from the individual buildings that eventually would be uses as essential information for building energy efficiency rating system.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.2
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• pp.143-150
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• 2013

Recently, environmental issues such as climate warming, ozone layer depletion, reduction of tropical forests and desertification are emerging as global environmental problems beyond national problems. And international attention and effort have been carried out in many ways to solve these problems. In this study, the growth of green was calculated quantitatively using the technique of remote sensing and temperature change was figured out through temperature extraction in the city. The land-cover changes and thermal changes for research areas were analyzed using Landsat TM images on May 2002 and May 2009. Surface temperature distribution was calculated using spectral degree of brightness of Band 6 that was Landsat TM thermal infrared sensor to extract the ground surface temperature in the city. As a result of research, the area of urban green belt was increased by $2.87km^2$ and the ground surface temperature decreased by $0.6^{\circ}C{\sim}0.8^{\circ}C$ before and after tree planting projects. Henceforth, if the additional study about temperature of downtown is performed based on remote sensing and measurement data, it will contribute to solve the problems about the urban environment.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.2
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• pp.208-214
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• 2012

The spectral radiance received by a remote sensor is consisted of the self-emitted component directly from the target surface, the reflected component of the solar irradiance at the target surface, and the scattered component by the atmosphere without ever reaching the object surface. In general, the self-emitted component is the most important part in the infrared signatures from the target. We measured the solar irradiation, sky irradiation, air temperature, wind velocity, wind direction, relative humidity, and atmospheric pressure together with the surface temperatures of rectangular parallelepiped targets. The measured diurnal surface temperature variations on the three different rectangular parallelepiped targets constructed by the steel, aluminum and bakelite are obtained at the same time intervals. The measured surface temperature results show that the top surface temperature of bakelite recorded up tp $7.6^{\circ}C$ higher than that of aluminium and $6.1^{\circ}C$ higher than that of steel at 11 AM on the sunny condition. A complete set of measured data including the surface temperature of rectangular parallelepiped targets together with the detailed weather information can be a valuable reference for future study.

• Journal of Biomedical Engineering Research
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• v.28 no.2
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• pp.169-173
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• 2007

During laser irradiation, mechanically deformed cartilage undergoes a temperature dependent phase transformation resulting in accelerated stress relaxation. Clinically, laser-assisted cartilage reshaping may be used to recreate the underlying cartilaginous framework in structures such as ear, larynx, trachea, and nose. Therefore, research and identification of the biophysical transformations in cartilage accompanying laser heating are valuable to identify critical laser dosimetry and phase transformation of cartilage for many clinical applications. quasi-elastic light scattering was investigated using Ho : YAG laser $(\lambda=2.12{\mu}m\;;\;t_p\sim450{\mu}s)$ and Nd:YAG Laser $(\lambda=1.32{\mu}m\;;\;t_p\sim700{\mu}s)$ for heating sources and He : Ne $(\lambda=632.8nm)$ laser, high-power diode pumped laser $(\lambda=532nm)$, and Ti : $Al_2O_3$ femtosecond laser $(\lambda=850nm)$ for light scattering sources. A spectrometer and infrared radiometric sensor were used to monitor the backscattered light spectrum and transient temperature changes from cartilage following laser irradiation. Analysis of the optical, thermal, and quasi-elastic light scattering properties may indicate internal dynamics of proteoglycan movement within the cartilage framework during laser irradiation.

• Journal of the Korean institute of surface engineering
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• v.35 no.5
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• pp.305-311
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• 2002

Optical measurements have been used to study the biaxial tensile strain in heteroeptaxial ZnTe epilayers on the (100) GaAs substrate by hot wall epitaxy (HWE) with Zn reservoir. It is effect on the low-temperature photoluminescence spectrum of the material. Optimum growth condition has been determined by a four-crystal rocking curve (FCRC) and a low temperature photoluminescence measurement (PL). It was found that Zn partial pressure from Zn reservoir has a strong influence on the quality of grown films. Under the determined optimum growth condition, ZnTe epitaxial films with thickness of 0.72~24.8$\mu\textrm{m}$ were grown for studying the effect of the thickness on crystalline quality. The PL and FCRC results indicated that the quality of ZnTe films becomes higher rapidly with increase of thickness up to 6$\mu\textrm{m}$. The best value of the FWHM of the four crystal rocking curve, 66 arcsec, was obtained on the film with 12$\mu\textrm{m}$ in thickness. The PL spectrum shows the splitted strong free exciton emissions and very weak deep band emissions. These results show the high quality of films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.135-139
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• 2005

Thin films of $BaTiO_3$ system were prepared by radio frequency(rf)/dc magnetron sputtering method. We have investigated crystal structure, surface morphology and PTCR(positive-temperature coefficient of resistance) characteristics of the specimen depending on second heat-treatment temperatures. Second heat treatments of the specimen were performed in the temperature range of 400 to $1350^{\circ}C$. X-ray diffraction patterns of $BaTiO_3$ thin films show that the specimen heat treated below $600^{\circ}C$ is an amorphous phase and the one heat treated above $1100^{\circ}C$ forms a poly-crystallization. In the specimen heat-treated at $1300^{\circ}C$, a lattice constant ratio (c/a) was 1.188. Scanning electron microscope(SEM) image of $BaTiO_3$ thin films of the specimen heat treated in between 900 and $1100^{\circ}C}$ shows a grain growth. At $1100^{\circ}C$, the specimen stops grain-growing and becomes a poly-crystallization.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.2
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• pp.1-6
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• 2008

In recent years, developments in the semiconductor and electronic industries have brought a rapid increase in the use of large size silicon wafer. For further improvement of the ultra precision surface and flatness of Si wafer necessary to high density ULSI, it is known that polishing is very important. However, most of these investigation was experiment less than 300mm diameter. Polishing is one of the important methods in manufacturing of Si wafers and in thinning of completed device wafers. This study reports the machining variables that has major influence on the characteristic of wafer polishing. It was adapted to polishing pressure, machining speed, and the slurry mix ratio, the optimum condition is selected by ultra precision wafer polishing using load cell and infrared temperature sensor. The optimum machining condition is selected a result data that use a pressure and table speed data. By using optimum condition, it achieves a ultra precision mirror like surface.