• Journal of Technologic Dentistry
• /
• v.36 no.3
• /
• pp.149-158
• /
• 2014

Purpose: Dental casting Co-Cr-Mo based alloys of five kinds of ingot type and two kinds of shot type were analyzed the melting processes with heating time of high frequency induction centrifugal casting machine using infrared thermal image analyzer. Methods: When Co-Cr-Mo based alloys were put about 30g/charge in the ceramic crucible of high frequency induction centrifugal casting machine and heat, Infrared thermal image analyzer and IR thermometer indicated these alloys in the crucible were set and operated. Results: The melting temperatures of alloys measuring infrared thermal image analyzer were deviated ${\pm}10^{\circ}C$ compared to those of manufacturing company. On the other hand, the melting time of alloys were differently appeared with the shape of alloys(ingot and shot type). Conclusion: The melting temperatures of dental Co-Cr-Mo based alloys were measured the degree of $1,360{\sim}1410^{\circ}C$ and the heating time with the alloys of ingot and shot type were deviated ${\pm}10sec$.

• Journal of the Korean Solar Energy Society
• /
• v.39 no.6
• /
• pp.55-65
• /
• 2019

With the rapid development of the national industry, the importance of electrical safety was recognized because of a lot of new electrical equipment are installing and the electrical accidents have been occurring annually. Today, the electrical equipments is inspect by using the portable Infrared thermal imaging camera. but the most negative element of using the camera is inspected for only state of heating, the reliable diagnosis is depended with inspector's knowledge, and real-time monitoring is impossible. This paper present the infrared thermal imaging safety diagnosis system. This system is able to monitor in real time, predict the state of fault, and diagnose the state with analysis of thermal and power data. The system consists of a main processor, an infrared camera module, the power data acquisition board, and a server. The diagnostic algorithm is based on a mathematical model designed by analyzing the Pearson's Correlation Coefficient between temperature and power data. To test the prediction algorithm, the simulations were performed by damaging the terminals or cables on the switchboard to generate a large amount of heat. Utilizing these simulations, the developed prediction algorithm was verified.

• Journal of Sensor Science and Technology
• /
• v.15 no.3
• /
• pp.179-185
• /
• 2006

We have developed a noncontact temperature sensor using a silver halides infrared optical fiber. An infrared radiation from a heat source is transferred by a silver halides infrared optical fiber and measured by infrared sensors such as a thermopile and a thermal optical power-meter. The relationships between the temperature of a heat source and the output voltage of the thermopile and the optical power of a thermal optical power-meter are determined. The measurable temperature range using a thermopile and a thermal optical power-meter are from 100 to $750^{\circ}C$ and from 30 to $750^{\circ}C$ respectively. It is expected that a noncontact temperature sensor using infrared optical fiber can be developed for medical and industrial usages based on the results of this study.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.12 no.2
• /
• pp.97-103
• /
• 2017

Thermal imaging is mainly used in military equipment required for night observation. In particular, technologies of uncooled thermal imaging detectors are being developed as applied to low-cost night observation system. Many system integrators require different specifications of the uncooled thermal imaging camera but their development time is short. In this approach, EOSYSTEM has developed a small size, TEC-less uncooled thermal imaging camera module with $32{\times}32mm$ size and low power consumption. Both domestic detector and import detector are applied to the EOSYSTEM's thermal imaging camera module. The camera module contains efficient infrared image processing algorithms including : Temperature compensation non-uniformity correction, Bad/Dead pixel replacement, Column noise removal, Contrast/Edge enhancement algorithms providing stable and low residual non-uniformity infrared image.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.06a
• /
• pp.172-173
• /
• 2007

As the power density and switching frequency increase, thermal analysis of power electronics system becomes imperative. The thermal analysis provides valuable information on the semiconductor rating, long-term reliability. In this paper, thermal distribution of the Non Punchthrough(NPT) Insulated Gate Bipolar Transistor has been studied. For analysis of thermal distribution, we obtained experimental and simulation results by using finite element simulator, Ansys and by using photographic infrared thermometer, we compared experimental date with simulation result. and got good agreement. Also this paper provided thermal distribution of IGBT connected to heat sinks. and this results will be good information to design optimal heat sink for IGBT.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2004.11a
• /
• pp.143-152
• /
• 2004

Researchers seeking geological and environmental information, depend on remote sensing and aerial photographic datum from various commercial satellites and aircraft. However, adverse weather conditions as well as equipment expense limit the ability to collect data anywhere and anytime. To allow for better flexibility in geological and environmental data collection, we have developed a compact, multi-spectral automatic Aerial Photographic system (PKNU2). This system's Multi-spectral camera can record visible (RGB) and infrared (NIR) band (3032＊2008 Pixels) images Visible and infrared band images were obtained from each camera respectively and produced color-infrared composite images to be analyzed for the purpose of the environmental monitoring. However this did not provide quality data. Furthermore, it has the disadvantage of having the stereoscopic overlap area being 60% unsatisfied due to the 12 seconds of storage time of each data The PKNU2 system in contrast, photographed photos of great capacity Thus, with such results, we have been proceeding to develop the advanced PKNU2 (PKNU3) system that consists of a color-infrared spectral camera that can photograph in the visible and near-infrared bands simultaneously using a single sensor, a thermal infrared camera, two 40G computers to store images, and an MPEG board that can compress and transfer data to the computer in real time as well as be able to be mounted onto a helicopter platform.

• Journal of Astronomy and Space Sciences
• /
• v.21 no.4
• /
• pp.467-480
• /
• 2004

It is very important to eliminate thermal background radiation for the near infrared camera system such as KAONICS (KAO Near Infrared Camera System). Thermal background radiations which come from window and cryostat wall influence IR detector and decrease IR system performance. Therefore the cold box which contains optics and detector housing must be cooled down to eliminate thermal background radiation. We carried out quantitative analysis to determine internal cooling temperature to reduce thermal noise in the J, H, Ks, and L bandpass. Additionally, we estimated the incoming heat load and then chose the cryocooler adequate to KAONICS's requirements. The cooling time and the final cooling temperature of the cold box were calculated. These results were also implemented to the system design.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.36 no.2
• /
• pp.130-137
• /
• 2016

Non-destructive testing methods for composite materials (e.g., carbon fiber-reinforced and glass fiber-reinforced plastic) have been widely used to detect damage in the overall industry. This study detects defects using optical infrared thermography. The transient heat transport in a solid body is characterized by two dynamic quantities, namely, thermal diffusivity and thermal effusivity. The first quantity describes the speed with thermal energy diffuses through a material, whereas the second one represents a type of thermal inertia. The defect detection rate is increased by utilizing a lock-in method and performing a comparison of the defect detection rates. The comparison is conducted by dividing the irradiation method into reflection and transmission methods and the irradiation time into 50 mHz and 100 mHz. The experimental results show that detecting defects at 50 mHz is easy using the transmission method. This result implies that low-frequency thermal waves penetrate a material deeper than the high-frequency waves.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.2
• /
• pp.329-336
• /
• 2022

Unreadable Khitan scripts of ancient documents written by indian ink on parchment(sheepskin) are visualized by active infrared thermography without contacting and damaging the document which are deteriorated and aged presumably over many years. Sinusoidal infrared thermal wave using Halogen lamp is applied to the surface of the document in order to selectively magnify and record the thermal response of indian ink. The infrared image of the document captured in real time by infrared camera under the active external excitation shows the better sharpness and readability of Khitan characters than the optical image, from which many Khitan letters like ' ' and ' ' sounding as 'd' and 'ri' in English alphabet are detected and deciphered. It is concluded from the experiment that the active infrared thermography can be used as a promising method for digital reconstruction and preservation of ancient documents in the future.

• Journal of Photoscience
• /
• v.9 no.2
• /
• pp.194-196
• /
• 2002

While ultraviolet radiation alters various cutaneous cell functions, little is known about photo-immunological and photobiological effects of infrared radiation (IR) on the skin except its local thermal effects. The fIrst part of this study demonstrated that single exposure of mouse skin to near IR (0.7 - 1.3 $\mu$m) reversibly suppressed the proliferating activity of the epidermis, the density of Langerhans cells, and the ability of skin to induce contact hypersensitivity reaction. The second part demonstrated that the rate of wound closure was significantly accelerated by repeated exposures in animal models. The production of transforming growth factor-$\beta$l and matrix metalloproteinase-2, which are responsible for the wound healing processes, was significantly upregulated by irradiation, as shown by enzyme immunoassay, zymography, and reverse transcription polymerase chain reaction. Thermal controls were negative. The results suggest that near-IR irradiation can modulate the epidermal proliferation and part of the skin immune system, and stimulate the wound healing processes, presumably by non-thermal effects.