• Title/Summary/Keyword: Temperature imaging

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Structural and temperature coefficient of resistance characteristics of colossal magnetoresistance Mn oxides prepared by RF sputtering

  • Choi, Sun-Gyu;Ha, Tae-Jung;Reddy, A.Sivasankar;Yu, Byoung-Gon;Park, Hyung-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.361-361
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    • 2007
  • A lot of efforts have been paid to develop infrared imaging systems in last decades. Bolometer has a wide range of applications from military to commercial, such as military night vision, medical imaging system and so on. Bolometer is a resistive sensor that detects temperature changes through resistance change. To improve detecting ability, bolometer should have a good resistive film which has high temperature coefficient of resistance (TCR) value. Colossal magnetoresistance (CMR) $L_{1-x}A_xMnO_3$ (where L and A are trivalent rare-earth ions and divalent alkaline earth ions, respectively.) are received attention to apply bolometer resistive film because it has a high TCR property which was discovered in the metal to semiconductor phase transition temperature region. In this work, CMR films were deposited on various substrates in relative low substrate temperature by RF magnetron sputtering. The influence of deposition parameters such as substrate temperature, gas partial pressure, and so on have been studied. The structural and TCR properties of the films were also investigated for applying to microbolometer.

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Preliminary Study on Image Processing Method for Concrete Temperature Monitoring using Thermal Imaging Camera (열화상카메라 기반 콘크리트 온도 측정을 위한 이미지 프로세싱 적용 기초 연구)

  • Mun, Seong-Hwan;Kim, Tae-Hoon;Cho, Kyu-Man
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.206-207
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    • 2020
  • Accurate estimation of concrete strength development at early ages is a critical factor to secure structural stability as well as to speed up the construction process. The temperature generated from the heat of hydration is considered as a key parameter in predicting the early age strength. Conventionally, concrete temperature has been measured by temperature sensors installed inside concrete. However, considering the measurement on building structures with multiple floors, this method requires reinstallation and repositioning of hardware such as sensors, data loggers and routers for data transfer. This makes the temperature monitoring work cumbersome and inefficient. Concrete temperature monitoring by using thermal remote sensing can be an effective alternative to supplement those shortcomings. In this study, image processing was carried out through K-means clustering technique, which is a unsupervised learning method, and the classification results were analyzed accordingly. In the future, research will be conducted on how to automatically recognize concrete among various objects by using deep learning techniques.

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Digital Infrared Thermal Imaging of Crape Myrtle Leaves Infested with Sooty Mold

  • Kim, Jiyeon;Kweon, Si-Gyun;Park, Junhyung;Lee, Harim;Kim, Ki Woo
    • The Plant Pathology Journal
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    • v.32 no.6
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    • pp.563-569
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    • 2016
  • The spatial patterns for temperature distribution on crape myrtle leaves infested with sooty mold were investigated using a digital infrared thermal imaging camera. The mean temperatures of the control and sooty regions were $26.98^{\circ}C$ and $28.44^{\circ}C$, respectively. In the thermal images, the sooty regions appeared as distinct spots, indicating that the temperatures in these areas were higher than those in the control regions on the same leaves. This suggests that the sooty regions became warmer than their control regions on the adaxial leaf surface. Neither epidermal penetration nor cell wall dissolution by the fungus was observed on the adaxial leaf surface. It is likely that the high temperature of black leaves have an increased cooling load. To our knowledge, this is the first report on elevated temperatures in sooty regions, and the results show spatial heterogeneity in temperature distribution across the leaf surface.

Study of Optimal Conditions Affecting the Photothermal Effect and Fluorescence Characteristics of Indocyanine Green

  • Seo, Sung Hoon;Bae, Min Gyu;Park, Hyeong Ju;Ahn, Jae Sung;Lee, Joong Wook
    • Current Optics and Photonics
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    • v.5 no.5
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    • pp.554-561
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    • 2021
  • Indocyanine green (ICG) is a cyanine dye that has been used in medical diagnostics based on fluorescence imaging, and in medical therapy based on the photothermal effect. It is important to systematically understand the photothermal effect and fluorescence characteristics of ICG simultaneously. By varying a number of conditions such as laser power density, laser irradiation wavelength, concentration of ICG solution, and exposure time of laser irradiation, the intensity properties of fluorescence and the temperature change induced by the photothermal effect are measured simultaneously using a charge-coupled-device camera and a thermal-imaging camera. The optimal conditions for maximizing the photothermal effect are determined, while maintaining a relatively long lifetime and high efficiency of the fluorescence for fluorescence imaging. When the concentration of ICG is approximately 50 ㎍/ml and the laser power density exceeds 1.5 W/cm2, the fluorescence lifetime is the longest and the temperature induced by the photothermal effect rapidly increases, exceeding the critical temperature sufficient to damage human cells and tissues. The findings provide useful insight into the realization of effective photothermal therapy, while also specifying the site to be treated and enabling real-time treatment monitoring.

Infrared Thermal Imaging in Patients with Medial Collateral Ligament Injury of the Knee - A Retrospective Study

  • Yang, HyunJung;Park, HaeIn;Lim, Chungsan;Park, SangKyun;Lee, KwangHo
    • Journal of Pharmacopuncture
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    • v.17 no.4
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    • pp.50-54
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    • 2014
  • Objectives: Digital infrared thermographic imaging (DITI) has been used widely for various inflammatory diseases, circulatory diseases, skin diseases, musculoskeletal diseases and cancers. In cases of ligament injury, obviously the temperature of the damaged area increases due to local inflammation; however, whether the temperature also increases due to DITI has not been determined. The purpose of the present study was to identify whether or not the changes of temperature in patient's with medial collateral ligament injury were really due to infrared thermography and to determine the applicability of DITI for assessing ligament injuries. Methods: Twenty patient's who underwent DITI for a medial collateral ligament injury from September 2012 to June 2014 were included in the current study. The thermographic images from the patient's knees were divided to cover seven sub-areas: the middle of the patella, and the inferomedial, the inferolateral, the superomedial, the superolateral, the medial, and the lateral regions of patella. The temperatures of the seven regions were measured, and the temperature differences between affected and unaffected regions were analyzed by using the Wilcoxon signed rank test. Results: The 20 patient's were composed of 14 women (70%) and 6 men (30%), with a mean age of $62.15{\pm}15.71$ (mean${\pm}$standard deviation (SD)) years. The temperature of the affected side, which included the middle of the patella, and the inferomedial, the superomedial, the superolateral, and the medial regions, showed a significant increase compared to that of the unaffected side (P < 0.05). The inferolateral and the lateral regions showed no significant changes. Conclusion: Our study results suggest that DITI can show temperature changes if a patient has a ligament injury and that it can be applied in the evaluation of a medial collateral ligament injury.

Small Camera Module for TEC-less Uncooled Thermal Image (TEC-less 비냉각 열영상 검출기용 소형카메라 모듈 개발)

  • Kim, Jong-Ho
    • IEMEK Journal of Embedded Systems and Applications
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    • v.12 no.2
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    • pp.97-103
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    • 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.

Motility Contrast Imaging for Drug Screening Applications

  • Jeong, Kwan
    • Journal of the Optical Society of Korea
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    • v.19 no.4
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    • pp.382-389
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    • 2015
  • Motility contrast imaging is a coherence-domain imaging technique that uses cellular motility as a fully endogenous imaging contrast agent. Motility is measured inside tissue using a digital holographic coherence gate that extracts dynamic speckle from fixed depths. The dynamic speckle arises from the normal organelle motion inside cells, and from the movement of the cellular membranes driven by the cytoskeleton. It measures cellular activity and the effects of temperature and osmolarity. Motion is sensitive to cytoskeletal drugs, such as the antimitotic drugs used for cancer chemotherapy, and the effects of drug combinations also can be monitored. Motility contrast imaging is a potential tissue-based assay platform for highthroughput screening of pharmaceuticals.

A Method for Evaluating the Temperature Coefficient of a Compound Semiconductor Energy Gap by Infrared Imaging Technique (적외선 영상기법에 의한 화합물 반도체 에너지갭의 온도계수 측정 방법)

  • Kang, Seong-Jun
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.38 no.5
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    • pp.338-346
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    • 2001
  • An infrared imaging method in which direct measurement of energy gap variations can be achieved by digital image processing is proposed. This method allows economic and easy evaluation of the temperature coefficients of a semiconductor energy gap. The key components of the method are a polychromator, a computer equipped with a frame grabber and a variable temperature cryostat. Tentative experimentation conducted on LEC grown semi-insulating GaAs has resulted in a fairly good agreement with the theoretical model. This proposed method could be applicable for most compound semiconductors.

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ASSESSMENT OF INFERIOR ALVEOLAR NERVE DAMAGE USING DIGITAL INFRARED THERMOGRAPHIC IMAGING (디지털 적외선 체열 검사를 사용한 하치조 신경 손상의 평가)

  • Lee, Ji-Yeon;Lee, Jae-Hoon;Kim, Chul-Hwan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.30 no.6
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    • pp.488-496
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    • 2004
  • Oral & Maxillofacial surgery can lead to complications that result in abnormal sensation or movement. Inferior alveolar nerve(IAN) injury can result in dysesthesia, paresthsia of the lower lip and chin, so patients presenting with IAN damage suffer from sensory loss. But diagnosis of the nerve injury is largely limited to the subjective statements made by the patient. Distribution of sympathetic nerves parallels the distribution of the somatosensory nerves. Loss of sensory tone causes a concomitant loss of sympathetic activity, resulting in vasodilation of the cutaneous blood vessels that demonstrates greater heat loss. Digital infrared thermographic imaging(DITI) detects infra-red radiation given off by body. DITI can detect minute difference in temperature from different parts of the body and translates the amount of heat into quantitative data. The area of different temperature correlated with pain or disease can be visualized by corresponding color. The objective of this study was to determine the efficacy of DITI in objectively assessing IAN injury. The 19 normal subjects and the 14 patients underwent DITI scan. The normal subjects received unilateral IAN block anesthesia with 2 ml of 2% lidocaine (IAN bolck group) to evaluate temporary alteration in nerve function. Patient group were patients with unilateral IAN damage (dysesthesia or paresthesia) after surgical treatment(Mn. 3rd molar Extraction, etc.). The surgical procedure performed within 6 months of test. The results were as follows. 1. No significant differences in temperature were found between left and right sides of the lower lip and chin in the control group. 2. Significant temperature differences were found between the anesthetized and non-anesthetized sides of the lower lip and chin in the IAN block group. 3. Significant temperature differences were found between the involved and uninvolved sides of the lower lip and chin areas of the experimental group. The results of the study show that DITI can be an useful and effective means of objectively assessing and visualizing IAN damage.

Effects of Qigong therapy on the thermal changes of upper, middle, lower $Danj{\breve{o}}n$(Ex-HN3, CV17, CV4) examined by Digital Infrared Thermographic Imaging(DITI) (기공체조(氣功體操)가 DITI로 촬영한 상(上), 중(中), 하단전(下丹田)의 체표온도(體表溫度)에 미치는 영향(影響))

  • Nam, Sang-Soo;Lee, Kyung-Sub
    • Journal of Oriental Medical Thermology
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    • v.1 no.1
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    • pp.47-51
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    • 2002
  • Objectives : It is the object of Qigong therapy to promote the circulation of Qi and blood, and to relieve mentality by way of warming lower Danjon. In this study, to prove that Qigong therapy could actually subside heat on upper or middle Danjon and warm the temperature on lower Danjon, we observed the thermal changes of upper, middle, lower Danjon before and after Qigong therapy and compared them. Methods : We selected 16 patients, treated Qigong therapy and examined by D.I.T.I.(Digital Infrared Thermographic Imaging) before and after Qigong therapy, among patients who visited. Qigong clinic, Kangnam Korean hospital, Kyunghee University(Daechi-2dong, Kangnam-Gu) from april to october, 1999. We watched the difference of temperature among upper, middle, lower Danjon before and after Qigong therapy, and used student T-test(paired type, 2 tail) for proving effects of Qigong therapy statistically. Conclusions 1. The difference of temperature$({\Delta}T)$ between upper(Ex-HN3) and lower Danjon(CV4) significantly decreased about $0.55^{\circ}C$ after Qigong therapy(p<0.01). 2. The difference of temperature${\Delta}T$ between middle(CV17) and lower Danjon(CV4) significantly decreased about $0.39^{\circ}C$ after Qigong therapy(p<0.05). 3. The difference of temperature${\Delta}T$ between upper(Ex-HN3) and middle Danjon(CV17) decreased about $0.25^{\circ}C$ after Qigong therapy, but it was not statistically significant.

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