• Title/Summary/Keyword: TIR

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PRELIMINARY STUDY OF ASTER DATA APPLICATIONS IN THAILAND

  • Anan, Thanwarat
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1005-1005
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    • 2003
  • The purpose of this study is to evaluate the potential application of TERRA-ASTER data in Thailand. ASTER VNIR, SWIR and TIR data covering greater Bangkok and Chiangmai province were processed with various techniques in the spatial domain to study the applicability to various disciplines. ASTER data was also combined with other satellite data in order to utilize multi-sensor methods. It was found that VNIR data can clearly identify urban pattern including road network and vegetation index. While SWIR and TIR data can well separate between urban and non urban area and TIR data can differentiate among thermal surfaces. Furthermore, dense urban areas such as central business area could be highlighted. Land utilization, vegetable distribution and differences of temperature distribution were investigated.

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A study on the Design and Application of a TIR Lens for Realizing A Compact Spot-Type UV Curing Machine Optical System (컴팩트한 Spot형 UV 경화기 광학계를 구현하기 위한 TIR 렌즈 설계 및 응용에 관한 연구)

  • Kim, Yu-Rim;Heo, Seung-Ye;Lee, Sang-Wook;Kim, Wan-Chin
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.2
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    • pp.255-264
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    • 2022
  • The conventional spot-type UV curing machine configures a collimator optical system using a plurality of lenses so that the light beam is incident through an optical cable. In order to increase the transmission light efficiency, a collimator optical system composed of three or more lenses is required, and accordingly, it is difficult to align the optical system, and it is difficult to implement the system compactly. In this study, a single TIR lens collimator that can realize the same level of spot diameter and light efficiency as the conventional collimator optical system composed of three lenses was designed. Through this, the light efficiency at the curing area with the minimum illuminance deviation was 33.2 %, which was similar to the performance of the reference collimator optical system, and the illuminance deviation on the curing area was 18.8 %, ensuring acceptable performance. In addition, by arranging a fly-eye lens with field flattening function at the front end of the condensing lens, the effective curing area diameter was reduced from 5.0 mm to 3.0 mm, enabling higher curing energy density to be realized. In addition, it was confirmed that the illuminance deviation can be greatly improved to a level of 14.4%.

Using ASTER TIR imagery to identify Heat Islands: A case study of New Jersey (ASTER 열적외선 이미지를 이용한 열섬 현상 탐지: 뉴저지를 사례로)

  • Park, Gwang yong;David W. Gwynn;David A. Robinson
    • Proceedings of the KGS Conference
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    • 2004.05a
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    • pp.56-56
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    • 2004
  • The ability to detect urban heat islands in satellite imagery is a function of spatial, spectral, and temporal resolutions. Imagery from the satellite-mounted Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor acquired since December 1999 allows us to view the Earth at a higher spectral resolution in the thermal infrared (TIR) portion of the electromagnetic spectrum than most other satellite systems (e.g., AVHRR, Landsat TM). (omitted)

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Change Detection Comparison of Multitemporal Infrared Satellite Imagery Using Relative Radiometric Normalization (상대 방사 정규화를 이용한 다시기 적외 위성영상의 변화탐지 비교)

  • Han, Dongyeob;Song, Jeongheon;Byun, Younggi
    • Korean Journal of Remote Sensing
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    • v.33 no.6_3
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    • pp.1179-1185
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    • 2017
  • The KOMPSAT-3A satellite acquires high-resolution MWIR images twice a day compared to conventional Earth observing satellites. New radiometric information of Earth's surface can be provided due to different characteristics from existing SWIR images or TIR images. In this study, the difference image of multitemporal images was generated and compared with existing infrared images to find the characteristics of KOMPSAT-3A MWIR satellite images. A co-registration was performed and the difference between pixel values was minimized by using PIFs (Pseudo Invariant Features) pixel-based relative normalization. The experiment using Sentinel-2 SWIR image, Landsat 8 TIR image, and KOMPSAT-3A MWIR image showed that the distinction between artifacts in the difference image of KOMPSAT-3A is prominent. It is believed that the utilization of KOMPSAT-3A MWIR images can be improved by using the characteristics of IR image.

Study of a Searchlight Lens to Improve Optical Performance and Fabricability (광학 성능 및 제작성 향상을 위한 탐조등 렌즈 연구)

  • Jo, Ye-Ji;Jung, Mee-Suk
    • Korean Journal of Optics and Photonics
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    • v.31 no.2
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    • pp.81-87
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    • 2020
  • This study examines the design technology of searchlight optics featuring narrow beam angles and high luminous intensities. Halogen and xenon lamps, which are conventional searchlight sources, are vulnerable to vibration and shock, and are large and heavy, making them difficult to transport. In addition, the parabolic mirror located at the rear of the searchlight has the disadvantages of poor performance and low light efficiency, due to the assembly error produced during manufacturing. To solve this problem, a 1-kW halogen lamp is replaced by a 150-W high-power COB LED, and a high-efficiency TIR lens is designed to meet the target performance. Afterward, the TIR lens array is proposed to solve the surface error generated during optical injection. After a prototype is manufactured based on the designed optical system, the optical performance is confirmed to be excellent, by comparing it to that of a commercial halogen-lamp searchlight.

Expression and Purification of Toll-like Receptor 9 Cytoplasmic Domain in Pichia patoris (Pichia pastoris로부터 Toll-like Receptor 9의 세포 내 도메인 단백질의 발현과 순수분리 정제)

  • Lee Kyun-Young;Lee Kon-Ho
    • Journal of Plant Biotechnology
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    • v.32 no.4
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    • pp.269-273
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    • 2005
  • Toll-like receptors (TLR) are important components of innate immunity in the defense against pathogens. TLRs recognize pathogen-associated common molecular patterns. TLRs are similar to the receptors involved in defense responses in plants. TLR protein is a type 1 membrane protein, consisting of an extracellular domain containing leucine-rich repeats and a cytoplasmic domain. The cytoplasmic domain delivers ligand recognition signals that result in production of anti-microbial agents. The cytoplasmic domain (amino acid 858-1032) of toll-like receptor 9 has been expressed using methylotrophic yeast Pichia pastoris. The protein expression was confirmed by Western-blot, N-terminal sequencing and MALDl-TOF mass spectrometry. The proteins have been purified by nickel affinity, cation exchange and gel-filtration chromatography.

Design and Analysis of U-shaped Sampled Grating Distributed Bragg Reflector Lasers (U형 Sampled Grating DBR 레이저 다이오드의 설계 및 분석)

  • Kim, Kyoungrae;Chung, Youngchul
    • Korean Journal of Optics and Photonics
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    • v.28 no.5
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    • pp.229-235
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    • 2017
  • A widely tunable U-shaped SGDBR (Sampled Grating Distributed Bragg Reflector) laser diode is designed and analyzed by means of a time-domain simulation. The U-shaped SGDBR laser diode consists of SGDBR, active, phase, and TIR (Total Internal Reflection) mirror sections, so the coupling losses across the sections should be carefully considered. The tuning range of the designed U-shaped SGDBR laser is about 1525-1570 nm, which is confirmed by the simulation. The simulation results show that the loss in the TIR mirror region should be less than about 2 dB, and the refractive-index difference at the butt coupling between the passive and active regions should be less than 0.1, to provide the complete tuning range.

Vegetation Monitoring using Unmanned Aerial System based Visible, Near Infrared and Thermal Images (UAS 기반, 가시, 근적외 및 열적외 영상을 활용한 식생조사)

  • Lee, Yong-Chang
    • Journal of Cadastre & Land InformatiX
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    • v.48 no.1
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    • pp.71-91
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    • 2018
  • In recent years, application of UAV(Unmanned Aerial Vehicle) to seed sowing and pest control has been actively carried out in the field of agriculture. In this study, UAS(Unmanned Aerial System) is constructed by combining image sensor of various wavelength band and SfM((Structure from Motion) based image analysis technique in UAV. Utilization of UAS based vegetation survey was investigated and the applicability of precision farming was examined. For this purposes, a UAS consisting of a combination of a VIS_RGB(Visible Red, Green, and Blue) image sensor, a modified BG_NIR(Blue Green_Near Infrared Red) image sensor, and a TIR(Thermal Infrared Red) sensor with a wide bandwidth of $7.5{\mu}m$ to $13.5{\mu}m$ was constructed for a low cost UAV. In addition, a total of ten vegetation indices were selected to investigate the chlorophyll, nitrogen and water contents of plants with visible, near infrared, and infrared wavelength's image sensors. The images of each wavelength band for the test area were analyzed and the correlation between the distribution of vegetation index and the vegetation index were compared with status of the previously surveyed vegetation and ground cover. The ability to perform vegetation state detection using images obtained by mounting multiple image sensors on low cost UAV was investigated. As the utility of UAS equipped with VIS_RGB, BG_NIR and TIR image sensors on the low cost UAV has proven to be more economical and efficient than previous vegetation survey methods that depend on satellites and aerial images, is expected to be used in areas such as precision agriculture, water and forest research.

Estimation of Sea Surface Temperature Change by Tide Embankment Construction

  • Shin Dong-hoon;Lee Kyoo-seock
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.146-148
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    • 2005
  • This study investigates to detect sea surface temperature (SST) and land cover change after tide embankment construction using Landsat Thematic Mapper (TM) thermal infrared (TIR) band data at Shihwa Lake and surrounding area. SST measurement is important for studies of both the structure of the ocean and as the thermal boundary between the ocean and the atmosphere. The TIR band of TM images can be used to detect SST change whose shoreline is complicated and narrow like the study site. The purpose of this study is to estimate SST and land cover change at Shihwa Lake and surrounding area.

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