• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.8
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• pp.624-628
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• 2013

With the recent development of less-costly uncooled detector technology, expensive optics are among the remaining significant cost drivers in the thermography camera. As a potential solution to this problem, the fabrication of IR lenses using chalcogenide glass has been studied in recent years. We report on the molding and evaluation of a ultra-precision chalcogenide-glass lens for the thermography camera for body-temperature monitoring. In addition, we fabricated prototype thermography camera using the chalcogenide-glass lens and obtained the thermal image from the camera. In this work, it was found out that thermography camera discerned body-temperature between 20 and $50^{\circ}C$ through the analysis of thermal image. It is confirmed that thermography camera using the chalcogenide-glass lens is applicable to the body-temperature monitoring system.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.10-12
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• 2006

The successful use of adhesively bonded parts depends on the defect-free bond of the components. Therefore it is necessary to detect relevant faults and defects in an early state of the production. A 100% test should be pursued, but especially at complicated structures the detection of defects is not easy. Possible testing methods, which show a high potential for the NDT of adhesively bonded parts, are thermography based NDT methods. At present mainly two different procedures of active thermography are being used: Pulse and Lock-In Thermography. With pulse thermography the examined material is warmed up with a short energy pulse (light, eddy current or ultrasonic pulse) and the heat response is recorded after a certain time. The result is an infrared image which indicates material defects in different depths. This paper presents a variety of images showing the capability of Lock-In Thermography to image subsurface defects. Several examples of adhesives joints qualify the ultrasonic Lock-In-Thermography for the in-process quality control for adhesive bonded components.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.6
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• pp.407-413
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• 2015

Ultrasonic infrared thermography is an active thermography methods. In this method, mechanical energy is introduced to a structure, it is converted into heat energy at the defects, and an infrared camera detects the heat for inspection. The heat generation mechanisms are dependent on many factors such as structure characteristics, defect type, excitation method and contact condition, which make it difficult to predict heat distribution in ultrasonic infrared thermography. In this paper, a method to simulate frictional heating, known to be one of the main heat generation mechanisms at the closed defects in metal structures, is proposed for ultrasonic infrared thermography. This method uses linear vibration analysis results without considering the contact boundary condition at the defect so that it is intuitive and simple to implement. Its advantages and disadvantages are also discussed. The simulation results show good agreement with the modal analysis and experiment result.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.1 no.1
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• pp.9-14
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• 1995

Thermography is a diagnostic procedures that measures infrared energy emitted by the skin. Thermography detects body temperature change which are controlled by the autonomic nervous system. It does show the thermal dysfunction that correlates closely with pain syndromes as well as normalization when the healing process takes place. Experienced clinical interpretation of the thermal pattern is necessary to diagnose and establish causation. Thermography is useful in the diagnosis of painful conditions such as herniated disc diseases, myofascial syndrome, myositis, musculoligamentous injury, reflex sympathetic dystrophy, athretic injuries, vascular diseases, arthritis, inflammation and breast tumors.

• Structural Engineering and Mechanics
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• v.80 no.5
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• pp.563-583
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• 2021

Composite materials, composed of multiple constituent materials with dissimilar properties, are actively adopted in a wide range of industrial sectors due to their remarkable strength-to-weight and stiffness-to-weight ratio. Nevertheless, the failure mechanism of composite materials is highly complicated due to their sophisticated microstructure, making it much harder to predict their residual material lives in real life applications. A promising solution for this safety issue is structural damage detection. In the present paper, damage detection of composite material via electrical resistance-based technique and infrared thermography is reviewed. The operating principles of the two damage detection methodologies are introduced, and some research advances of each techniques are covered. The advancement of IR thermography-based non-destructive technique (NDT) including optical thermography, laser thermography and eddy current thermography will be reported, as well as the electrical impedance tomography (EIT) which is a technology increasingly drawing attentions in the field of electrical resistance-based damage detection. A brief comparison of the two methodologies based on each of their strengths and limitations is carried out, and a recent research update regarding the coupling of the two techniques for improved damage detection in composite materials will be discussed.

• The Journal of Dong Guk Oriental Medicine
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• v.8 no.2
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• pp.47-67
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• 2000

The purpose of this study is to assess the usefulness of thermography in patients with musculoskeletal disease. Thermography is noninvasive, easy to reading, objective and physiologic instrument by measuring and imaging infrared energy emitted from skin surface. Thermography can show the skin temperature changes in various conditions of the body with musculoskeletal disease. This literature review was done for the usefulness of thermography in diagnosing musculoskeletal disease. In conclusion, thermography was adapted in radiculopathy, MPS, peripheral neuropathy, RSD, Raynaud's phenomen, TMJ dysfunction, etc. It was useful as a secondary diagnostic method in those diseases, also possible as a primary diagnostic method in RSD, Raynaud's phenomen. And, it might be reliable tool for estimating disease procedure and consequence after treatment. But, the objectivity of the reading and the development of the operating method are required for further adaptation in musculoskeletal disease.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.2
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• pp.144-149
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• 2011

The lock-in thermography was employed to evaluate the integrity of railway bogies. Prior to the actual application on railway bogies, in order to assess the detectability of known flaws, the calibration reference panel was prepared with various dimensions of artificial flaws. The panel was composed of structural steel, which was the same material with actual bogies. Through lock-in thermography evaluation, the optimal frequency of heat source was determined for the best flaw detection. Based on the defects information, the actual defect assessments on railway bogie were conducted with different types of railway bogies, which were used for the current operation. In summary, the defect assessment results with thermography method showed a good agreement as compared with the conventional inspection techniques. Moreover, it was found that the novel infrared thermography technique could be an effective way for the inspection and the detection of surface defects on bogies since the infrared thermography method provided rapid and non-contact mode for the investigation of railway bogies.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.1
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• pp.12-19
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• 2012

This study conducted infrared (IR) thermography tests using pipe and plate specimens with artificial wall-thinning defects to find an optimal condition for IR thermography test on the wall-thinned nuclear piping components. In the experiment halogen lamp was used to heat the specimens. The distance between the specimen and the lamp and the intensity of halogen lamp were regarded as experimental parameter. When the distance was set to 1~2 m and the lamp intensity was above 60 % of full power, a single scanning of IR thermography detected all artificial wall-thinning defects, whose minimum dimension was $2{\Theta}=90^{\circ}$, d/t=0.5, and $L/D_o=0.25$, within the pipe of 500 mm in length. Regardless of the distance between the specimen and the lamp, the image of wall-thinning defect in IR thermography became distinctive as the intensity of halogen lamp increased. The detectability of IR thermography was similar for both plate and pipe specimens, but the optimal test condition for IR thermography depended on the type of specimen.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.313-314
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• 2007

• Journal of Electrical Engineering and Technology
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• v.1 no.3
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• pp.376-380
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• 2006

Temperature distribution measured to estimate the condition of an electrical apparatus is an absolute reference for the apparatus conditions and the difference between the reference temperature and the current temperature. Because of passive thermography, without the external thermal stimulation, the difference in surface temperature between the region of interest and back ground shows that the results can apply only to the estimation or the monitoring for the condition of loose terminal and the overload pertaining to the rise in temperature. However, a thermal diffusion in the active thermography is differently generated by the structure and condition of the surface and subsurface. This paper presents a nondestructive test using this behavior and deals with the results by heat injection and cooling to the apparatus. The buried discontinuity of subsurface could be detected by these techniques.