• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.2
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• pp.40-48
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• 2012

Steel corrosion in concrete is a main cause of deterioration and early failure of concrete structures. A novel integration of electromagnetic heat induction and infrared (IR) thermography is proposed for nondestructive detection of steel corrosion in concrete, by taking advantage of the difference in thermal characteristics of corroded and non-corroded steel. This paper focuses on experimental investigation of the concept. An inductive heater is developed to remotely heat the embedded steel from concrete surface, which is integrated with an IR camera. Concrete samples with different cover depths are prepared. Each sample is embedded with a single rebar in the middle, resulting an identical cover depth from the front and the back surfaces, which enable heat induction from one surface and IR imaging from the other simultaneously. The impressed current (IC) method is adopted to induce accelerated corrosion on the rebar. IR video images are recorded during the entire heating and cooling periods. The test results demonstrate a clear difference in thermal characteristics between corroded and non-corroded samples. The corroded sample shows higher rates of heating and cooling than those of the non-corroded sample. This study demonstrates a potential for nondestructive detection of rebar corrosion in concrete.

• Korean Journal of Acupuncture
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• v.20 no.1
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• pp.1-20
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• 2003

This study was examined for effects of acupuncture of Zusanli (ST36) on the abdominal thermography of health subject. The volunteers who participating in this study had taken rest for 20-30 mins in room temperature (23-$25^{\circ}C$) before the examination and informed them what to prohibit smoking, drinking and administration of drug for the previous day. The thermography of abdomen including a below part of the chest was taken using Infra-Red Imaging System (IR 2000, MEDI-CORE Co, Korea) by time interval of 15 minutes at 15 min before, just before and 15 min after, 30 min after and 45 min after acupuncture stimulation. Acupuncture was applied to the left ST36 acupoint for 30 mins. The results showed that acupuncture of ST36 significantly had more potencies of changes on all the of abdominal thermography than those of control group. Also, it was observed that the quantities of thermal changes following acupuncture of ST36 been increased significantly comparing that of control group at all the ROIs (region of interest). Observed the thermography classified by ROI, however, it was failed that acupuncture of ST36 could modulate the specific areas concerning to the abdominal pathway of Stomach Meridian. These results suggest that acupuncture of ST36 may modulate thermal distributions and changes of abdominal areas including the below of chest.

• Korean Journal of Acupuncture
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• v.20 no.4
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• pp.1-16
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• 2003

Objectives : This study was examined for effects of acupuncture of Hyeong points' Acupuncture of Three Foot-eum Collaterals on the abdominal thermography of health subject. Methods : The volunteers who participating in this study had taken rest for 20 - 30 minutes in room temperature $(23-25^{\circ}C)$ before the examination and informed them what to prohibit smoking, drinking and administration of drug for the previous day. The thermography of abdomen including a below part of the chest was taken using Infra-Red Imaging System (IR 2000, MEDI-CORE Co., Korea) by time interval of 15 minutes at 15 minutes before, just before and 15 minutes after, 30 minutes after and 45 minutes after acupuncture stimulation. Acupuncture was applied to the left Hyeong points' Acupuncture of Three Foot-eum Collaterals for 30 minutes. Results : The results showed that acupuncture of Hyeong points had more potencies of changes on all the ROIs of abdominal thermography than those of control group. Also, it was observed that the quantities of thermal changes following acupuncture of Hyeong points been increased comparing that of control group at all the ROIs (region of interest). Observed the thermography classified by ROI, however, it was failed that acupuncture of Hyeong points could modulate the specific areas concerning to the abdominal pathway of Three Foot-eum Collaterals. Conclusions : These results suggest that acupuncture of Hyeong points may modulate thermal distributions and changes of abdominal areas including the below of chest.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.351-352
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• 2006

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.5
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• pp.484-488
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• 2010

Infrared emissivity is one of the most important factors for the temperature measurement by infrared thermography. Although the infrared emissivity of an object can be measured from the ratio of blackbody and the object, at room temperature it is practically difficult to measure the value due to the background effects. Hence, quantitative reflectance of bare steel plate and the surface of coating was measured by FT-IR spectroscopy and emissivity was calculated from this. The emissivity of polished bare steel surface was from 0.06 to 0.10 and the value for the unpolished bare steel can not be achieved because optical characteristics changes of surface roughness induces erroneous results. Emissivity of transparent paint coated steel was from 0.50 to 0.84. Depends on the IR absorption regions, which is a characteristic value of the coating, emissivity changes. This study suggests surface condition of material, thickness, roughness et cetra are important factor for IR optical characteristics. Emissivity measurement by reflection method is useful technique to be applied for metal and it with coating applied on the surface. The range of experimental errors of temperature can be narrowed by the application of infrared thermography from the measured thermal emissivity.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.2
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• pp.127-133
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• 2011

A LabVIEW program has been developed together with simple infrared thermography(IRT) system to control the lock-in conditions of the system efficiently. The IR imaging software was designed to operate both of infrared camera and halogen lamp by synchronizing them with periodic sine signal based on thyristor(SCR) circuits. LabVIEW software was programmed to provide users with screen-menu functions by which it can change the period and energy of heat source, operate the camera to acquire image, and monitor the state of the system on the computer screen. In experiment, lock-in IR image for a specimen with artificial hole defects was obtained by the developed IRT system and compared with optical image.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.1
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• pp.34-39
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• 2013

In the advanced research deducted infrared thermography (IRT) test using 4 inch pipe with artificial wall-thinning defect to measure on the wall-thinned nuclear pipe components. This study conducted for defect detection condition of nuclear small-bore pipe research using deducted condition in the advanced research. Defect process is processed by change for defect length, circumferential direction angle, wall-thinning depth. In the used equipment IR camera and two halogen lamps, whose full power capacitany is 1 kW, halogen lamps and Target pipe experiment performed to the distance of the changed 1 m, 1.5 m, 2 m. To analysis of the experimental results ensure for the temperature distribution data, by this data measure for defect length. artificial defect of 4 inch pipe is high reliability in the 2 m, but small-bore pipe is in the 1.5 m from the defect clearly was detected.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.5
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• pp.321-331
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• 2015

A study on the application of cooling defect detection was performed on the basis of a preceding study on the heated defect detection in nuclear piping loop system, using lock-in infrared thermography. A loop system with piping defects was made by varying the wall-thinning length, the circumference orientation angle, and the wall-thinning depth. The test was performed using an IR camera and a cooling device. Distance between the cooling device and the target loop system was fixed at 2 m. For analyzing experimental results, the temperature distribution data for cooling, and phase data were obtained. Through the analysis of this data, the defect length was measured. The reliability of the measurements for cooling defect conditions was shown to be higher in the lock-in infrared thermography data than the infrared thermography data.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.4
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• pp.323-329
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• 2013

This perform research of angle rated defect detection conditions and nuclear power plant piping defect detection by lock-In infrared thermography technique. Defects were processed according to change for wall-thinning length, Circumference orientation angle and wall-thinning depth. In the used equipment IR camera and two halogen lamps, whose full power capacitany is 1 kW, halogen lamps and target pipe's distance fixed 2 m. To analysis of the experimental results ensure for the temperature distribution data, by this data measure for defect length. Reliability of lock-In infrared thermography data is higher than Infrared thermography data. This through research, Shape of angle rated defect is identified industry place. It help various angles defect detection in the nuclear power plant in operation.

• Korean Journal of Acupuncture
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• v.20 no.2
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• pp.1-20
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• 2003

This study was examined for characteristics of acupuncture of LU10 on the abdominal thermography of health subject. The volunteers who participating in this study had taken rest for 20 - 30 mins in room temperature $(23-25^{\circ}C)$ before the examination and informed them what to prohibit smoking, drinking and administration of drug for the previous day. The thermography of abdomen including a below part of the chest was taken using Infra-Red Imaging System (IR 2000, MEDI-CORE Co., Korea) by time interval of 15 minutes at 15 min before, just before and 15 min after, 30 min after and 45 min after acupuncture stimulation. Acupuncture was applied to both LU10 for 30 mins. The results showed that acupuncture of LU10 for 30 mins had more potencies of changes on all the ROIs of abdominal thermography than those of control group. Also, those responses were significantly clear at the A1, A3, A6, A7 and A9 areas. It was observed that the quantities of thermal changes following acupuncture of LU10 been increased significantly comparing that of control group at the all ROIs (region of interest). These effects have more potencies at the upper (A1 and A2) and below (A7, A8, A9) abdominal areas than midline ones (A4, A5, and A6). These results suggest that acupuncture of LU10 having the characteristics of controls of chill and fever (寒熱) may modulate thermal distributions and changes of abdominal areas including the below of chest.