• Title/Summary/Keyword: Heat detection

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Histological Detection of Phytoalexin Scoparone from Heat-Treated and UV-Illuminated Lemon Fruits After Inoculation with Penicillium digitatum

  • Kim, Jong-Jin;Yehoshua, Shimshon-Ben
    • The Plant Pathology Journal
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    • v.17 no.5
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    • pp.271-275
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    • 2001
  • Phytoalexin scoparone (6,7-dimethoxycoumarin) was induced in flavedo tissue of lemon fruit inoculated with Penicillium digitatum during heat treatment for 3 days at $36^{\circ}$. The compound was also induced in the flavedo tissue after UV illuminatiion. Induction of scoparone was deteected in the flavedo tissue by histological analysis. This fluorescent scoparone accumulated only on the 4-5 layers of cells adjacent to the inoculation site. Preinoculation with P. digitatum and subsequent heat-treatment induced resistance in the lemon fruit tissues after challenge-inoculation at the site of the first infection. the data obtained in the study suggest that lemon fruit acquired resistance against P. digitatum parallel with the scoparone production at the infection site.

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Development of laser tailored blank weld quality monitoring system (레이저 테일러드 블랭크 용접 품질 모니터링 시스템 개발)

  • 박현성;이세헌
    • Laser Solutions
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    • v.3 no.2
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    • pp.53-61
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    • 2000
  • On the laser weld production line, a slight alteration of the welding condition produces many defects. The defects are monitored in real time, in order to prevent continuous occurrence of defects, reduce the loss of material, and guarantee good quality. The measurement system is produced by using three photo-diodes for detection of the plasma and spatter signal in CO$_2$ laser welding. For high speed CO$_2$ laser welding, laser tailored welded blanks for example, on-line weld quality monitoring system was developed by using fuzzy multi-feature pattern recognition. Weld qualities were classified optimal heat input, a little low heat input, low heat input, and focus misalignment, and final weld quality were classified good and bad.

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Contour Integral Method for Crack Detection

  • Kim, Woo-Jae;Kim, No-Nyu;Yang, Seung-Yong
    • Journal of the Korean Society for Nondestructive Testing
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    • v.31 no.6
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    • pp.665-670
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    • 2011
  • In this paper, a new approach to detect surface cracks from a noisy thermal image in the infrared thermography is presented using an holomorphic characteristic of temperature field in a thin plate under steady-state thermal condition. The holomorphic function for 2-D heat flow field in the plate was derived from Cauchy Riemann conditions to define a contour integral that varies according to the existence and strength of a singularity in the domain of integration. The contour integral at each point of thermal image eliminated the temperature variation due to heat conduction and suppressed the noise, so that its image emphasized and highlighted the singularity such as crack. This feature of holomorphic function was also investigated numerically using a simple thermal field in the thin plate satisfying the Laplace equation. The simulation results showed that the integral image selected and detected the crack embedded artificially in the plate very well in a noisy environment.

Numerical Simulation on the Heat and Smoke Flow Phenomena Due to the Fire in a Cyclodrome (경륜장 내부의 화재발생에 따른 열 및 연기 거동에 대한 수치적 연구)

  • 박원희;김태국;손봉세
    • Fire Science and Engineering
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    • v.17 no.3
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    • pp.13-19
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    • 2003
  • In this paper, numerical calculations are conducted to predict the characteristics of the heat transfer and smoke propagation in a cydodrome. The gas flow velocity and temperature around the origin of the fire is obtained by using a plume model and the turbulent flow characteristics are considered by standard $textsc{k}$-$\varepsilon$ turbulent model. In this study, the transient thermal behavior can be used for designing fire detection of large rooms.

Design and Fabrication of Micro Laser Module for Heat Assisted Magnetic Recording (차세대 열 보조 자지기록용 마이크로 레이저 모듈 설계 및 제작)

  • Lee, S.C.;Choi, Y.B.;Kim, Y.J.;Kim, D.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.68-69
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    • 2009
  • Heat Assisted Magnetic Recording (HAMR) is one of the most promising candidates for high density magnetic storages over 1 Tb/$in^2$ areal density. Since the precise light delivery to the head is a key factor to realize HAMR application, it is required to establish the light delivery using micro laser module and micro actuator. For the careful control of micro actuator, a laser module was designed including laser diode, optical fiber, collimating lens, and fabricated V-groove substrate. In addition, the basic aligning method between the laser module and HAMR head was studied by the detection of current change in photo diode due to the amount of reflected light from the head.

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Fault Diagnosis of Variable Speed Refrigeration System Based on Current Information

  • Lee, Dong-Gyu;Jeong, Seok-Kwon;Hua, Li
    • International Journal of Air-Conditioning and Refrigeration
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    • v.16 no.4
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    • pp.137-144
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    • 2008
  • This study deals with on-line fault detection and diagnosis(FDD) for heat exchangers of a variable speed refrigeration system(VSRS) based on current information. The current residual which is the difference between real detected current from current sensors and estimated current from no fault model was utilized to diagnose faults of the heat exchangers. Comparing to the conventional FDD of constant refrigeration system based on temperature and pressure information, the suggested FDD method shows better robustness to the VSRS which has a feedback control loop. Moreover the suggested method can be expected more precise and faster diagnosis of faults about heat exchangers. Throughout some experiments, the validity of the method was verified.

Object and Heat Detection by Isothermal Images (열화상 등온선 기반 객체 구분과 온도 인식에 관한 연구)

  • Lee, Jinseok
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.04a
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    • pp.389-392
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    • 2010
  • 기존에 없던 열화상 카메라의 기능에서 온도가 일정 수준 이상인 지점을 여러 지점 표시하는 알고리즘을 추가하였다. 또한 산업 현장뿐만 아니라 이번에 발생한 신종 플루도 감지하기 위해서 열을 통해 사람을 구분하는 방법을 추가하였다.