• Title/Summary/Keyword: Active IR

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Analyses of temperature change of a u-bolometer in Focal Plane Array with CTIA bias cancellation circuit (CTIA 바이어스 상쇄회로를 갖는 초점면 배열에서 마이크로 볼로미터의 온도변화 해석)

  • Park, Seung-Man
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.12
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    • pp.2311-2317
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    • 2011
  • In this paper, we study the temperature change of a ${\mu}$-bolometer focal plane array with a capacitive transimpedance amplifier bias cancellation circuit. Thermal analysis is essential to understand the performance of a ${\mu}$-bolometer focal plane array, and to improve the temperature stability of a focal plane array characteristics. In this study, the thermal analyses of a ${\mu}$-bolometer and its two reference detectors are carried out as a function of time. The analyses are done with the $30{\mu}m$ pitch $320{\times}240$ focal plane array operating of 60 Hz frame rate and having a columnwise readout. From the results, the temperature increase of a ${\mu}$-bolometer in FPA by an incident IR is estimated as $0.689^{\circ}C$, while the temperature increase by a pulsed bias as $7.1^{\circ}C$, which is about 10 times larger than by IR. The temperature increase of a reference detector by a train of bias pulses may be increased much higher than that of an active ${\mu}$-bolometer. The suppression of temperature increase in a reference bolometer can be done by increasing the thermal conductivity of the reference bolometer, in which the selection of thermal conductivity also determines the range of CTIA output voltage.

Real-Time Eye Detection and Tracking Under Various Light Conditions

  • Park Ho Sik;Nam Kee Hwan;Seol Jeung Bo;Cho Hyeon Seob;Ra Sang Dong;Bae Cheol Soo
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.862-866
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    • 2004
  • Non-intrusive methods based on active remote IR illumination for eye tracking is important for many applications of vision-based man-machine interaction. One problem that has plagued those methods is their sensitivity to lighting condition change. This tends to significantly limit their scope of application. In this paper, we present a new real-time eye detection and tracking methodology that works under variable and realistic lighting conditions. Based on combining the bright-pupil effect resulted from IR light and the conventional appearance-based object recognition technique, our method can robustly track eyes when the pupils are not very bright due to significant external illumination interferences. The appearance model is incorporated in both eyes detection and tracking via the use of support vector machine and the mean shift tracking. Additional improvement is achieved from modifying the image acquisition apparatus including the illuminator and the camera.

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Slotted type copper ion laser (Slot형 구리 이온 레이저)

  • 송순달;홍남관
    • Korean Journal of Optics and Photonics
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    • v.8 no.4
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    • pp.291-296
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    • 1997
  • The slotted type of hollow copper cathode was constructed and tested for its geometric stability and usability for laser operation at 780nm. The peak output power of copper ion laser emission was measured for different operating conditions. The IR-laser power was dependent on the parameters of the geometry of the hollow cathodes, discharge current and gas fillings. The peak power decreased with increasing neon pressure over 60%. One reason for this decrease in output power may be conjectured as hier due to the decreasing population of the upper laser level. The copper ion laser transition at 780 nm populated at the 5p level. The hollow cathode copper ion laser is operated in He and Ne mixture by electric discharge excitation and could be operated for more than 100 hours with only a 35% drop in the output power(2.8mW cw for 9.6cm active length).

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Real Time Discrimination of 3 Dimensional Face Pose (실시간 3차원 얼굴 방향 식별)

  • Kim, Tae-Woo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.3 no.1
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    • pp.47-52
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    • 2010
  • In this paper, we introduce a new approach for real-time 3D face pose discrimination based on active IR illumination from a monocular view of the camera. Under the IR illumination, the pupils appear bright. We develop algorithms for efficient and robust detection and tracking pupils in real time. Based on the geometric distortions of pupils under different face orientations, an eigen eye feature space is built based on training data that captures the relationship between 3D face orientation and the geometric features of the pupils. The 3D face pose for an input query image is subsequently classified using the eigen eye feature space. From the experiment, we obtained the range of results of discrimination from the subjects which close to the camera are from 94,67%, minimum from 100%, maximum.

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A Development of Video Monitoring System on Real Time (실시간 영상감시 시스템 개발)

  • Cho, Hyun-Seob
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.2
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    • pp.240-244
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    • 2007
  • Non-intrusive methods based on active remote IR illumination fur eye tracking is important for many applications of vision-based man-machine interaction. One problem that has plagued those methods is their sensitivity to lighting condition change. This tends to significantly limit their scope of application. In this paper, we present a new real-time eye detection and tracking methodology that works under variable and realistic lighting conditions. Based on combining the bright-pupil effect resulted from IR light and the conventional appearance-based object recognition technique, our method can robustly track eyes when the pupils are not very bright due to significant external illumination interferences. The appearance model is incorporated in both eyes detection and tracking via the use of support vector machine and the mean shift tracking. Additional improvement is achieved from modifying the image acquisition apparatus including the illuminator and the camera.

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Synthesis and Emulsifying Properties for Dipropylene Glycol Succinate (디프로필렌글리콜 숙시네이트의 합성 및 유화특성)

  • Jeong, Noh-Hee;Kang, Mi-Na;Choi, Sung-Ok
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.1
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    • pp.47-53
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    • 2012
  • This study is concerned with coemulsifier which is better emulsifiable properties than emulsifier itselves' use only. It's compound was synthesized by esterification of propylene glycol and succinic acid. The structure of them was comfirmed with FT-IR and $^1H$-NMR. Surface active properties with surface tension, cmc, emulsing power were tested respectively at given conditions. Their surface tensions in the aqueous solution was decreased to 33-35 dyne/cm and their cmc was evaluated by surface tension method. And it's emulsifying power was excellent in jojoba oil. As results, the synthesized dipropylene glycol succinate is expected to apply as O/W coemulsifier.

Isolation of 3,4-Dihydroxybenzoic Acid with Antimicrobial Activity from Bark of Aralia elata (두릅수피에서 항미생물활성을 갖는 3,4- dihydroxybenzoic acid의 분리)

  • Ma, Seung-Jin;Ko, Byoung-Seub;Park, Keun-Hyung
    • Korean Journal of Food Science and Technology
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    • v.27 no.5
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    • pp.807-812
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    • 1995
  • The methanol extracts of Aralia elata bark showed antimicrobial activities against bacteria, yeast, fungi. The solvent fractionated acidic fraction that showed the activity was then successively purified with silica gel adsorption column chromatography, Sephadex LH-20 column chromatography, silica gel partition column chromatography, HPLC and TLC. The isolated major active substance was identified as 3,4-dihydroxybenzoic acid by MS, GC-MS, IR, $^{1}H-NMR\;and\;^{13}C-NMR$. The content of 3,4-dihydroxybenzoic acid was 0.869㎎/g in dried bark of Aralia elata.

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Isolation and Identification of an Unauthorized Sildenafil Analogue in a Commercial Functional Food (시판 기능성식품으로부터의 실데나필 유도체 부정첨가물질의 분리 및 구조규명)

  • Baek, Du-Jong
    • Journal of the Korean Chemical Society
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    • v.54 no.4
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    • pp.443-446
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    • 2010
  • HPLC analysis of a commercial herb drink marketed as a functional food revealed to contain an unauthorized substance similar to sildenafil, the active ingredient of the prescription drug Viagra$^{(R)}$ approved for the treatment of male erectile dysfunction. In order to identify the illegal additive, the herb drink was extracted with methylene chloride, and the extract was purified further using semipreparative HPLC. The chemical structure of the isolated substance was elucidated based on IR, LC/MS-ESI, and NMR spectroscopy, which showed the characteristics similar to sildenafil with minor modification. The only difference was the substitution of the methylpiperazine moiety of sildenafil to the hydroxyethylpiperazine group of the illegal additive.

Purification and Biological Activities of MT 1155 Inducing Morphological Change of Rous Sarcoma Virus-Transformed Normal Rat Kidney Cell (Rous Sarcoma Virus에 의해 형질전환된 NRK 세포의 형태변화를 유도하는 활성물질 MT 1154의 분리와 생물학적 활성)

  • 안종석;박문수;박찬선;윤병대;민태익;안순철;오원근;이현선;윤병대
    • Microbiology and Biotechnology Letters
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    • v.21 no.1
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    • pp.59-65
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    • 1993
  • We isolated Actinomycetes strain GMT 1155 and purified the active compound, MT 1155, on the morphological reversion of ts/NRK cell from the isolate. MT 1155 was identified as toyocamycin having antifungal and antitumor activities from physico-chemical properties and UV, IR, $^1H$-NMR, $^13C$-NMR and mass spectrum. MT 1155 showed the morphologically reversional activity on ts/NRK cell and the cytotoxicity on CTLL cell at the final concentrations of 1.7 JlM and 0.2 11M, respectively and its $IC_{50}$ value on protein kinase A enzyme was 2.3 $\mu$M. Also it had strong antifungal activity against several pathogenic fungi but not antibacterial activity. And it did not inhibit both protein kinase C activity and the bleb-formation of K562 cell induced by phorbol esters.

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Real-Time Eye Detection and Tracking Under Various Light Conditions (다양한 조명하에서 실시간 눈 검출 및 추적)

  • 박호식;배철수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.2
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    • pp.456-463
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    • 2004
  • Non-intrusive methods based on active remote IR illumination for eye tracking is important for many applications of vision-based man-machine interaction. One problem that has plagued those methods is their sensitivity to lighting condition change. This tends to significantly limit their scope of application. In this paper, we present a new real-time eye detection and tacking methodology that works under variable and realistic lighting conditions. Based on combining the bright-Pupil effect resulted from IR light and the conventional appearance-based object recognition technique, our method can robustly track eyes when the pupils ale not very bright due to significant external illumination interferences. The appearance model is incorporated in both eyes detection and tacking via the use of support vector machine and the mean shift tracking. Additional improvement is achieved from modifying the image acquisition apparatus including the illuminator and the camera.