• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.2
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• pp.73-79
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• 2021

Recently there are growing interests on the energy conservation and emission reduction. In the fields of architecture and civil engineering, the energy monitoring of structures is required to response the energy issues. In perspective of thermal monitoring, thermal images gains popularity for their rich visual information. With the rapid development of the drone platform, aerial thermal images acquired using drone can be used to monitor not only a part of structure, but wider coverage. In addition, the stereo photogrammetric process is expected to generate 3D point cloud with thermal information. However thermal images show very poor in resolution with narrow field of view that limit the use of drone-based thermal photogrammety. In the study, we aimed to generate 3D thermal point cloud using visible and thermal images. The visible images show high spatial resolution being able to generate precise and dense point clouds. Then we extract thermal information from thermal images to assign them onto the point clouds by precisely establishing photogrammetric collinearity between the point clouds and thermal images. From the experiment, we successfully generate dense 3D thermal point cloud showing 3D thermal distribution over the building structure.

• Journal of the Ergonomics Society of Korea
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• v.31 no.3
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• pp.427-435
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• 2012

The aim of this study is to investigate facial temperature changes induced by facial expression and emotional state in order to recognize a persons emotion using facial thermal images. Background: Facial thermal images have two advantages compared to visual images. Firstly, facial temperature measured by thermal camera does not depend on skin color, darkness, and lighting condition. Secondly, facial thermal images are changed not only by facial expression but also emotional state. To our knowledge, there is no study to concurrently investigate these two sources of facial temperature changes. Method: 231 students participated in the experiment. Four kinds of stimuli inducing anger, fear, boredom, and neutral were presented to participants and the facial temperatures were measured by an infrared camera. Each stimulus consisted of baseline and emotion period. Baseline period lasted during 1min and emotion period 1~3min. In the data analysis, the temperature differences between the baseline and emotion state were analyzed. Eyes, mouth, and glabella were selected for facial expression features, and forehead, nose, cheeks were selected for emotional state features. Results: The temperatures of eyes, mouth, glanella, forehead, and nose area were significantly decreased during the emotional experience and the changes were significantly different by the kind of emotion. The result of linear discriminant analysis for emotion recognition showed that the correct classification percentage in four emotions was 62.7% when using both facial expression features and emotional state features. The accuracy was slightly but significantly decreased at 56.7% when using only facial expression features, and the accuracy was 40.2% when using only emotional state features. Conclusion: Facial expression features are essential in emotion recognition, but emotion state features are also important to classify the emotion. Application: The results of this study can be applied to human-computer interaction system in the work places or the automobiles.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.2
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• pp.68-71
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• 2006

Active thermography has been used for several years in the field of remote non-destructive testing. It provides thermal images for remote detection and imaging of damages. Also, it is based on propagation and reflection of thermal waves which are launched from the surface into the inspected component by absorption of modulated radiation. For energy deposition, it use external heat sources (e.g., halogen lamp or convective heating) or internal heat generation (e.g., microwaves, eddy current, or elastic wave). Among the external heat sources, the ultrasound is generally used for energy deposition because of defect selective heating up. The heat source generating a thermal wave is provided by the defect itself due to the attenuation of amplitude modulated ultrasound. A defect causes locally enhanced losses and consequently selective heating up. Therefore amplitude modulation of the injected ultrasonic wave turns a defect into a thermal wave transmitter whose signal is detected at the surface by thermal infrared camera. This way ultrasound thermography(UT) allows for selective defect detection which enhances the probability of defect detection in the presence of complicated intact structures. In this paper the applicability of UT for fast defect detection is described. Examples are presented showing the detection of defects in PCB material. Measurements are performed on various kinds of typical defects in PCB materials (both Cu metal and non-metal epoxy). The obtained thermal image reveals area of defect in row of thick epoxy material and PCB.

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.206-207
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• 2001

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.210-211
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• 2001

• Journal of Korean Tunnelling and Underground Space Association
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• v.14 no.3
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• pp.197-213
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• 2012

Disc cutter is a key cutting tool for rock excavation by TBMs. This study aimed to characterize the deformation of a cutter ring by strain measurement as well as infrared thermal camera measurement during a series of linear cutting tests for a hard rock. The strain measurement results indicated that the cutter ring clearly showed a linear elastic behavior. The data obtained from the infrared thermal camera measurement demonstrated that the maximum temperature increase in the cutter ring was below $14.4^{\circ}C$. The deformation and temperature increase of the cutter ring during rock cutting were insignificant in a given cutting test condition of this study.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.597-598
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• 2013

A lot of fire and crime accidents are caused to a significant national loss. For example, the network and power facilities in national industry facilities, the fire risk region in large scale factories such as nuclear and thermal power plants, large-sized buildings, cultural properties, metal and steel mills, chemical plants, oil refineries. The development of a fire detection system that can detects the temperature and movement of objects as high-level quality is essential to prevent these incidents and accidents fundamentally. In this paper, the fire detection system based on infrared thermal imaging & CCD camera id designed to solve these problems.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.4
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• pp.592-604
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• 2019

This study examines the stealth function of sputtered fabric with an infrared thermal imaging camera in terms of the thermal and infrared (IR) transmittance characteristics. Various base fabrics were selected, infrared imaging was performed, and infrared transmittance was measured. By infrared camera experiment it was found that the sample was concealed because it had a similar color to the surroundings when the aluminum layer was directed toward the outside. In addition, a comparison of the infrared thermographic image of the untreated sample and the sputtered sample in the laboratory showed that the difference in ${\Delta}E$ value ranged from 31 to 90.4 and demonstrated effective concealment. However, concealment was not observed in the case of the 3-layer (Nylon-Al-Nylon) model when a sputtered aluminum layer existed between two nylon layers. The direction of the sputtering layer did not affect the infrared transmittance in the infrared transmittance experiment. Therefore, it seems better to interpret the concealing effect in the infrared thermographic images by using thermal transfer theory rather than infrared transmittance theory. We believe that the results of this study will be applicable to developing high performance smart clothing and military uniforms.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.6_2
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• pp.935-941
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• 2020

In this study, the effect of different shapes on the heat dissipation characteristics of other porous frames on LED lighting frames was studied using finite element analysis. In addition, the heat transfer characteristics of LED frames were tested using a thermal imaging camera and the results of finite element analysis were compared to derive the optimal hole shape. According to the study, the heat dissipation effect was better for frames with hole compared to existing ones without holes. In particular, the heat dissipation characteristics test showed that for frames with holes, the rise time to the maximum temperature is fast and the maximum temperature is significantly lower. Also, we could see that the square and diamond shapes were smaller than the circular pores, but had a greater heat dissipation effect. Through this study, we have concluded that there is a limit to increasing the heat dissipation effect of the frame with a perforated shape, and it is necessary to conduct further research on the change in the shape of the frame in order to achieve a better heat dissipation effect in the future.

• Journal of Korea Society of Industrial Information Systems
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• v.27 no.1
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• pp.11-18
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• 2022

The use of multi-spectral cameras is essential for day and night pedestrian detection. In this paper, a color camera and a thermal imaging infrared camera were used to detect pedestrians near a crosswalk for 24 hours at an intersection with a high risk of traffic accidents. For pedestrian detection, the YOLOv5 object detector was used, and the detection performance was improved by using color images and thermal images at the same time. The proposed system showed a high performance of 0.940 mAP in the day/night multi-spectral (color and thermal image) pedestrian dataset obtained from the actual crosswalk site.