• Title/Summary/Keyword: Infrared(IR)

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Some interaction characteristics of IR radiation with ice crystals - New IR channel exploration

  • Xu, Lisheng;Ding, Jilie
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.352-357
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    • 2002
  • Some interaction characteristics, i.e., light scattering characteristics, of infrared (IR) radiation with small ice crystals are investigated systematically by using the exact T-matrix approach. Some important facts are obtained, which reveal, especially, that the combination of both the 25 and 3.979$\mu$m together has some advantages and potential applications for remote sensing of cirrus and other ice clouds. A new far-IR channel at the wavelength of 25$\mu$m is proposed.

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Thermal Analysis of a Cryochamber for an Infrared Detector Considering a Radiation Shield (적외선 검출기용 극저온 챔버에서 복사 차폐막을 고려한 열해석)

  • Kim Young-Min;Kang Byung-Ha
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.18 no.8
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    • pp.672-677
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    • 2006
  • The steady cooling characteristics of a cryochamber for infrared (IR) detector have been investigated analytically, considering radiation shields. The thermal modeling considers the conduction heat transfer through cold finger, the gaseous conduction due to out-gassing, and the radiation heat transfer. The cooling load of the cryochamber is obtained by using a fin equation. The results obtained indicate that the gaseous conduction plays an important role in determining the steady cooling load. The steady cooling load is increased as the gas pressure is increased. It is also found that the cooling load is substantially decreased with a radiation shield. The most thermal load of a cryochamber occurs through the cold finger.

Properties of Current due to Voltage in Heat Conductive Silicone Rubber (열전도성 실리콘 고무의 전압-전류 특성)

  • Lee, Sung-Ill
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.9
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    • pp.576-581
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    • 2014
  • This study used the heat conductive silicone rubber sample of 0.95 mm thickness to research the properties of current by changing voltage. When the 1, 10, 30, 60, and 90 minute have passed, the running current has been measured through the applied voltage range of 200 V~800 V on setting temperature of $110^{\circ}C{\sim}170^{\circ}C$. As the temperature increased in applied voltage of 800 V, so did the current value according to time in proportion to the increasing temperature. In an analysis of FT-IR (fourier transform infrared) spectrum, the hydroxyl radicals group(O-H) was created by effects of the hydrogen that methyl group is eliminated by addition of the cross-linking agent peroxide.

Neurilemmoma of Deep Peroneal Nerve Sensory Branch : Thermographic Findings with Compression Test

  • Ryu, Seung Jun;Zhang, Ho Yeol
    • Journal of Korean Neurosurgical Society
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    • v.58 no.3
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    • pp.286-290
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    • 2015
  • We report a case of neurilemmoma of deep peroneal nerve sensory branch that triggered sensory change with compression test on lower extremity. After resection of tumor, there are evoked thermal changes on pre- and post-operative infrared (IR) thermographic images. A 52-year-old female presented with low back pain, sciatica, and sensory change on the dorsal side of the right foot and big toe that has lasted for 9 months. She also presented with right tibial mass sized 1.2 cm by 1.4 cm. Ultrasonographic imaging revealed a peripheral nerve sheath tumor arising from the peroneal nerve. IR thermographic image showed hyperthermia when the neurilemoma induced sensory change with compression test on the fibular area, dorsum of foot, and big toe. After surgery, the symptoms and thermographic changes were relieved and disappeared. The clinical, surgical, radiographic, and thermographic perspectives regarding this case are discussed.

Target Adaptive Guidance Using Near-Zone Information from IR Seeker (근접영역에서의 IR 탐색기 정보를 이용한 표적적응유도)

  • 엄태윤;김필성
    • Journal of the Korea Institute of Military Science and Technology
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    • v.5 no.3
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    • pp.113-119
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    • 2002
  • A target adaptive guidance(TAG) algorithm is proposed employing the near-zone signal that can be measured from an infrared seeker. The guidance order is composed of a conventional PNG command and an additional command to be calculable from an additional LOS rate between a hot point of target and a required intercept point. The characteristic of the near-zone signal is similar to that of LOS rate that is inversely proportional to the square of time-to-go. Hence the proposed scheme can be applied to real systems with no estimator for time-to-go. From analysis results on the miss distance with perfect missile and perfect seeker, it follows that the proposed TAG algorithm guarantees missile to be ideally guided to the required intercept point. And it is less affected by the TAG start time and a proportional navigation ratio than other TAG schemes using a LOS rate such as a step bias or a ramp bias.

Low Power IR Module Design for Small Arms Using Un-cooled Type Detector (비냉각 검출기를 이용한 소화기용 저전력 열상모듈 설계)

  • Sung, Gi-Yeul;Kwak, Dong-Min;Kwak, Ki-Ho;Kim, Do-Jong;Lyou, Joon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.4
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    • pp.138-144
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    • 2007
  • This paper introduces the design techniques of an IR module using the 2-D array un-cooled type infrared detector which is applied to the individual combat weapon. Considering the size and weight of the hand carried weapon system, we used a very small-sized detector and applied an adaptive temperature control algorithm so that the operation consumed with low power can be possible. We applied the AR(Auto Regressive) filter to improve the signal-to-noise ratio in a thermal image processing step. We also applied the plateau equalization and boundary enhancement techniques to improve the visibility for human visual system.

Scientific Studies on Ancient Silk Fibers Used for Textiles Excavated at Archaeological Sites in Japan, Using Microscopic Fourier Transform Infrared Spectroscopy

  • SATO, Masanori
    • Journal of Conservation Science
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    • v.5 no.2 s.6
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    • pp.45-50
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    • 1996
  • Silk fibers excavated at Fujinoki mounted tomb, Shimoikeyana mounted tomb and Kuriyama site were examined using FT-IR microscope and two peaks called amide I and II present in modern silk fibers were compared with those of excavated fibers. It was found that amide ground in a polymer molecule decreased with the progress of degradation and peak intensity of amide group in infrared spectrum decreased correspondingly. The advantages of FT-IR microscopy for the analysis of organic remains in archaeological view point were evaluated and it was concluded that the systematic investigation of spectral change due to the degradation of respective material is essential.

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ONE TYPE OF EDDY DEVELOPMENT IN THE NORTHEASTERN KUROSHIO BRANCH

  • Bulatov, Nafanail V.;Kapshiter, Alexander V.;Obukhova, Natalya G.
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.926-929
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    • 2006
  • Some features of vertical structure of the frontal interaction zone of the warm Kuroshio Current and cold Oyashio Current are known from 1930 from analysis of ship data. Ship data however do not allow carrying out the area detailed survey opposite to satellite infrared (IR) observations which possess by high spatial and temporal resolution. Analysis of NOAA AVHRR IR images demonstrated that process of formation and development of the Kuroshio warm core rings is highly complex. They are formed as a result of development of anticyclonic meanders of the warm Kuroshio waters and spin off them from the current. Joint analysis of thermal infrared images and altimetry data has also indicated that interaction of eddies to the frontal zone plays a crucial role in formation of large eddies moving to the Southern Kuril region.

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A Fabrication of IR $CO_2$ Sensor based on the MEMS and Characteristic Evaluation (MEMS 기반의 IR $CO_2$ 센서 제작 및 특성 평가)

  • Kim Shin-Keun;Han Yong-Hee;Moon Sung-Wook
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.54 no.5
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    • pp.232-237
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    • 2005
  • In this paper, we fabricated $CO_2$ gas sensor based on the MEMS infrared sensor and characterized its electrical and $CO_2$-sensing properties. The fabricated $CO_2$ gas sensor by MEMS technique has many advanges over NDIR(nondispersive) $CO_2$ sensor such as monolithic fabrication, very high selectivity on $CO_2$, low power consumption and compact system. Microbolometer by surface micromachining was fabricated for gas detector and $CO_2$ filter chip by bulk micromachining was fabricated for signal referencing. By using the proposed and fabricated gas sensor, we are expected to measure $CO_2$ concentration more accurately with high reliability.

Analysis of Thermal Distribution inside LCD Monitor by Development of Prediction Formula for Inner Temperature (내부 온도 추정식 개발에 의한 LCD 모니터 내부의 열분포 분석)

  • Oh, S.J.;Ko, H.S.;Chung, D.H.
    • 유체기계공업학회:학술대회논문집
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    • 2006.08a
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    • pp.487-488
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    • 2006
  • In these days, demand of a LCD monitor is remarkably increasing with development of the LCD technology. However, there are thermal problems for improvement of efficiency for the LCD monitor. Thus, this research analyzed thermal problems such as convection and conduction heat transfer characteristics in the LCD monitor using an infrared (IR) camera. Also, the results of the outer side of the front LCD panel using the IR camera have been compared with the results of the inner side of the front panel using T-type thermocouples. The equations have been derived for the temperature distribution of the inner side of the front LCD panel by a multiple regression method including variables for ambient temperature, humidity and temperature differences between the front and back panels of the LCD monitor.

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