• Title/Summary/Keyword: 적외선 촬영기법

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Heat Transfer Measurement in a Supersonic Flowfield by an Infra-red Thermography (적외선 측정 기법을 이용한 초음속 유동내 열전달 측정)

  • Yu, Man-Sun;Yi, Jong-Ju;Song, Ji-Woon;Cho, Hyung-Hee
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2006.11a
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    • pp.359-362
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    • 2006
  • Infra-red thermography was conducted to understand a heat transfer characteristic on a surface protruded to a supersonic flowfield. Surface temperature distribution was obtained under the constant heat flux condition with a infra-red camera and the convective heat transfer coefficient distribution was calculated. Finally, two dimensional distribution of heat transfer coefficient on a surface around a cylinder body was derived.

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Corrosion Measurement Method Using Thermographical Information (열화상 정보를 이용한 부식률 예측기법)

  • Yun, Ju-Young;Chung, Lan;Roh, Young-Sook
    • Journal of the Korean Society for Nondestructive Testing
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    • v.27 no.2
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    • pp.142-147
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    • 2007
  • In order to measure corrosion level of steel reinforcement rebar which is inside reinforced concrete structure, infrared thermographic technique was employed. Experimental test parameters were four different ambient temperatures and various levels of corrosion states (0, 1, 3, 5, 7 and 10% of weight loss). After analysis of temperature distributions of concrete surface, the amount of heat flux from the concrete surface is directly proportional to the corrosion level which is inside of concrete.

Marker Swapping Elimination Mechanism Using Color Marker (컬러 마커를 이용한 마커 스와핑 제거 기법)

  • Kim, Byung-Ki;Jang, Jae-Hyok;Song, Chang Geun;Ko, Young-Woong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.04a
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    • pp.150-153
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    • 2010
  • 본 연구에서는 적외선 카메라를 이용하는 모션캡처 시스템에서의 전통적인 문제인 마커의 손실과 스왑을 해결할 수 있는 방법에 대해 제안한다. 기본적으로 적외선 센서를 이용하여 마커의 위치를 계산하여 모션을 캡처하는 방식을 사용한다. 여기에 각 마커에 식별이 가능한 고유한 아이디를 지정할 수 있게 하기 위해 적외선 반사판의 색깔을 다르게 제작하였다. 적외선 카메라를 이용하여 마커에서 반사되는 적외선의 좌표를 촬영하고 일반 카메라를 이용하여 마커의 위치와 색깔을 구별한다. 실험 결과 각 마커의 식별이 가능했으며 카메라를 들고 이동하면서도 정확하고 빠르게 모션을 캡처할 수 있음을 실험을 통해 증명하였다.

A study on Visualization and Enhancement the Latent Fingerprints on Multi-colored Surfaces using the Forensic Light Sources (법광원을 이용한 복잡한 배경의 잠재지문 시각화 및 증강에 관한 연구)

  • Cho, Hyeong-Woo;Koh, Hyun-Seo;Han, Sang-Gyoun;Yu, Je-Seol
    • The Journal of the Korea Contents Association
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    • v.16 no.3
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    • pp.72-80
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    • 2016
  • There are various methods of developing latent fingerprints from evidence found at crime scenes. Crime scene investigators should choose appropriate techniques among them depending on the conditions of the evidences. In this study, we compared the three methods using forensic light sources to develop latent fingerprints on multi-colored surfaces. We selected the various samples according to color, shape and texture of the surfaces and developed the latent fingerprints using fluorescent powder, IR(Infrared) photography and Episcopic Co-axial Illumination. Fluorescent powder was highly effective on all surfaces. IR photography was also effective, but only on the not dark surfaces. Episcopic Co-axial Illumination was effective only on the flat and polished surfaces. Although fluorescent powder was fine regardless of the characteristics of the surfaces, IR photography was better on certain surfaces.

Determination of an Test Condition for IR Thermography to Inspect a Wall-Thinning Defect in Nuclear Piping Components (원전 배관 감육 결함 검사를 위한 IR 열화상시험 조건 결정)

  • Kim, Jin-Weon;Yun, Won-Kyung;Jung, Hyun-Chul;Kim, Kyeong-Suk
    • 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.

Use of Digital Infrared Thermography on Experimental Spinal Cord Compression in Dogs (개에서 실험적으로 유발한 척수압박에 대한 적외선 체열촬영술의 적용)

  • Kim Wan-Tae;Kim Min-Su;Kim Sun Young;Seo Kang-Moon;Nam Tchi-Chou
    • Journal of Veterinary Clinics
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    • v.22 no.4
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    • pp.302-308
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    • 2005
  • This study was performed to examine the absolute skin temperature and temperature difference $({\Delta}T)$ between the left and the right, the upper and the lower parts on the back of dog and to investigate the clinical usefulness of infrared thermography as diagnostic or prognostic aid on experimental spinal cord compression by using Digital Infrared Imaging System. In normal dogs, symmetrical and contouring patterns were observed in thermogram. The skin temperature difference was not significant between the left and the right, the upper and the lower parts on the back. In spinal cord compressed dog, there was symmetrical temperature reduction pattern around lesion. Patterns of ${\Delta}T$ between thoracic and lumbar portions were remarkable and showed the tendency to return to normal after 4 weeks of operation. It is considered that infrared thermography is a useful diagnostic and prognostic aid for spinal cord injury in dogs.

Evaluation of Possibility for the Classification of River Habitat Using Imagery Information (영상정보를 활용한 하천 서식처 분류 가능성 평가)

  • Lee, Geun-Sang;Lee, Hyun-Seok
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.3
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    • pp.91-102
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    • 2012
  • As the basis of the environmental ecological river management, this research developed a method of habitat classification using imagery information to understand a distribution characteristics of fish living in a natural river. First, topographic survey and investigation of discharge and water temperature were carried out to analyze hydraulic characteristics of fish habitat, and the unmanned aerial photography was applied to acquire river imagery at the observation time. Riffle, pool, and glide regions were selected as river habitat to analyze fish distribution characteristics. Analysis showed that the standard deviation of RGB on the riffle is higher than pool and glide because of fast stream flow. From the classification accuracy estimation on riffle region according to resolution and kernel size using the characteristics of standard deviation of RGB, the highest classification accuracy was 77.17% for resolution with 30cm and kernel size with 11. As the result of water temperature observation on pool and glide using infrared camera, they were $19.6{\sim}21.3^{\circ}C$ and $15.5{\sim}16.5^{\circ}C$ respectively with the differences of $4{\sim}5^{\circ}C$. Therefore it is possible to classify pool and glide region using the infrared photography information. The habitat classification to figure out fish distribution can be carried out more efficiently, if unmanned aerial photography system with RGB and infrared band is applied.

Study on Obstacle Avoidance Algorithm of Autonomous Mobile Robots Using Infrared Sensor and Camera (적외선센서와 카메라를 이용한 자율주행로봇의 장애물회피 알고리즘 연구)

  • Jung Woo Sohn;Ho Sung Yun;Wansu Lim
    • Journal of the Institute of Convergence Signal Processing
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    • v.24 no.4
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    • pp.192-198
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    • 2023
  • This paper proposes an algorithm for autonomous mobile robots to effectively navigate obstacles. In order to detect obstacles infrared sensors and cameras are employed. The infrared sensor is utilized to calculate the distance to obstacles while the captured images from the camera are used to determine the width of obstacles. To compute obstacle width, binary image processing, contour detection, and the minimum area rectangle technique are employed. Using the distance to obstacles and obstacle width, the avoidance angle is calculated, and this angle is incorporated into steering control. The proposed obstacle avoidance algorithm was implemented on an autonomous robot, and experimental results demonstrated a maximum reduction in avoidance time by 8.5 seconds compared to using only infrared sensors when the obstacle width is 30cm.

Development of Combined Optical System for Analysis of Impinging Butane Flame (충돌 부탄 화염의 분석을 위한 복합 광학 계측 기법 개발)

  • Baek, Seung-Hwan;Ahn, Seong-Soo;Ko, Han-Seo
    • 한국가시화정보학회:학술대회논문집
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    • 2005.12a
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    • pp.69-73
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    • 2005
  • Three-dimensional density distributions of an impinging and eccentric flame have been analyzed numerically and experimentally by a combined optical system with a digital speckle tomography. The flame has been ignited by premixed butane/air from air holes and impinged vertically against a plate located at the upper side of tile burner nozzle. In order to compare with experimental data, computer synthesized phantoms of impinging and eccentric flames have been made and reconstructed by a developed three-dimensional multiplicative algebraic reconstruction technique (MART). A new scanning technique has been developed for the analysis of speckle displacements to investigate wall jet regions of the impinging flame including sharp variation of the flow direction and pressure gradient. The reconstructed temperatures have been compared with a temperature photography by an infrared camera and results of numerical analysis using a finite-element method.

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Fluvial Hyperspectral Image Analysis for Identifying Bed Materials and Bathymetry in Shallow Stream (초분광 영상 기반 저수심 하천 하상재료 및 수심 계측 기법 개발)

  • You, Ho Jun;Kim, Dong Su;Kim, Seo Jun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.101-101
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    • 2016
  • 하천원격탐사는 원격탐사의 하위 개념으로서 계측하고자 하는 대상인 하천이나 호소 수체에서 발생하는 빛의 반사, 복사 또는 방출되는 양을 획득하고 분석하여 수리량, 지형 등 하천 조사에 활용하는 기법이다. 일반적으로 원격탐사는 주로 위성영상 자료를 활용하여 수행되어 자료취득비용이 고가이고 해외 위성자료에 의존하여 시공간적인 해상도가 매우 낮아 유역에 비해 공간적인 규모가 작고 변동 시간이 짧은 하천에 적용하는 데 한계가 있어 왔다. 또한, 단순한 사진촬영으로 도출할 수 있는 정보에 한계가 있고 자료를 저장 및 분석할 수 있는 기법도 부족하여 하천조사에 원격탐사를 활용한 사례가 드물었다. 그러나, 최근 드론과 같은 운반체 기술이 획기적으로 개선되고 있고 다양한 영상촬영장비의 개발과 IT기술의 발전으로 인해 위성영상에 비해 시공간적 해상도가 매우 정밀한 자료를 저렴한 비용으로 획득 가능해졌다. 또한, 매우 조밀한 파장대로 세분된 빛의 세기를 측정할 수 있는 초분광 영상을 이용한 원격탐사기법도 하천과 같은 좁은 영역에 적용이 가능해졌다. 초분광영상은 가시광선 외에 자외선과 적외선 영역에 해당하는 반사광을 200개 이상의 조밀한 파장대로 나누어 측정할 수 있어 수리량, 하상, 식생 등 하천 수체와 관련된 정보를 조사할 가능성이 증가하였다. 본 연구에서는 하천 수체에서 취득한 초분광 영상을 이용하여 하천특성과의 상관관계를 규명하고 이를 통해 초분광 영상 기반의 하천특성 계측 기법을 개발하고자 하였다. 드론과 같은 항공영상에 적용하기 전에, 우선 지상에서 측정된 초분광 영상과 하상재료 및 수심과의 상관관계를 규명하여 초분광 영상의 하천조사로의 사용 가능성을 점검해 보았다. 폭 10m, 수심 1m의 저수심의 소하천에 적용한 결과, 초분광 영상의 표준화 및 패턴 분석을 통해 수중에 위치한 하상재료를 구분할 수 있었고 주성분분석 등을 통해 수심과 상관성도 일부 도출되어 하천조사에 초분광영상이 활용될 수 있음을 확인하였다.

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