• Title/Summary/Keyword: illumination environment

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Albedo Based Fake Face Detection (빛의 반사량 측정을 통한 가면 착용 위변조 얼굴 검출)

  • Kim, Young-Shin;Na, Jae-Keun;Yoon, Sung-Beak;Yi, June-Ho
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.45 no.6
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    • pp.139-146
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    • 2008
  • Masked fake face detection using ordinary visible images is a formidable task when the mask is accurately made with special makeup. Considering recent advances in special makeup technology, a reliable solution to detect masked fake faces is essential to the development of a complete face recognition system. This research proposes a method for masked fake face detection that exploits reflectance disparity due to object material and its surface color. First, we have shown that measuring of albedo can be simplified to radiance measurement when a practical face recognition system is deployed under the user-cooperative environment. This enables us to obtain albedo just by grey values in the image captured. Second, we have found that 850nm infrared light is effective to discriminate between facial skin and mask material using reflectance disparity. On the other hand, 650nm visible light is known to be suitable for distinguishing different facial skin colors between ethnic groups. We use a 2D vector consisting of radiance measurements under 850nm and 659nm illumination as a feature vector. Facial skin and mask material show linearly separable distributions in the feature space. By employing FIB, we have achieved 97.8% accuracy in fake face detection. Our method is applicable to faces of different skin colors, and can be easily implemented into commercial face recognition systems.

An Improved License Plate Recognition Technique in Outdoor Image (옥외영상의 개선된 차량번호판 인식기술)

  • Kim, Byeong-jun;Kim, Dong-hoon;Lee, Joonwhoan
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.5
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    • pp.423-431
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    • 2016
  • In general LPR(License Plate Recognition) in outdoor image is not so simple differently from in the image captured from manmade environment, because of geometric shape distortion and large illumination changes. this paper proposes three techniques for LPR in outdoor images captured from CCTV. At first, a serially connected multi-stage Adaboost LP detector is proposed, in which different complementary features are used. In the proposed detector the performance is increased by the Haar-like Adaboost LP detector consecutively connected to the MB-LBP based one in serial manner. In addition the technique is proposed that makes image processing easy by the prior determination of LP type, after correction of geometric distortion of LP image. The technique is more efficient than the processing the whole LP image without knowledge of LP type in that we can take the appropriate color to gray conversion, accurate location for separation of text/numeric character sub-images, and proper parameter selection for image processing. In the proposed technique we use DBN(Deep Belief Network) to achieve a robust character recognition against stroke loss and geometric distortion like slant due to the incomplete image processing.

User Detection and Main Body Parts Estimation using Inaccurate Depth Information and 2D Motion Information (정밀하지 않은 깊이정보와 2D움직임 정보를 이용한 사용자 검출과 주요 신체부위 추정)

  • Lee, Jae-Won;Hong, Sung-Hoon
    • Journal of Broadcast Engineering
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    • v.17 no.4
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    • pp.611-624
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    • 2012
  • 'Gesture' is the most intuitive means of communication except the voice. Therefore, there are many researches for method that controls computer using gesture input to replace the keyboard or mouse. In these researches, the method of user detection and main body parts estimation is one of the very important process. in this paper, we propose user objects detection and main body parts estimation method on inaccurate depth information for pose estimation. we present user detection method using 2D and 3D depth information, so this method robust to changes in lighting and noise and 2D signal processing 1D signals, so mainly suitable for real-time and using the previous object information, so more accurate and robust. Also, we present main body parts estimation method using 2D contour information, 3D depth information, and tracking. The result of an experiment, proposed user detection method is more robust than only using 2D information method and exactly detect object on inaccurate depth information. Also, proposed main body parts estimation method overcome the disadvantage that can't detect main body parts in occlusion area only using 2D contour information and sensitive to changes in illumination or environment using color information.

Biological Co2 Fixation to Antioxidant Carotenoids by Photosynthesis Using the Green Microalga Haematococcus pluvialis (광합성 녹색 미세조류 Haematococcus pluvialis를 이용한 이산화탄소 고정화 및 항산화성 카로티노이드 생산)

  • Kang, Chang Duk;Park, Tai Hyun;Sim, Sang Jun
    • Korean Chemical Engineering Research
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    • v.44 no.1
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    • pp.46-51
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    • 2006
  • As one of the $CO_2$ reduction strategies, a biological method was proposed to convert $CO_2$ to useful biomass with antioxidant carotenoids by photosynthetic microorganisms. One of the photoautotrophs, Haematococcus pluvialis is a freshwater green microalga and accumulates the secondary carotenoid astaxanthin during induction of green vegetative cells to red cyst cells. In this study, $CO_2$ fixation and astaxanthin production using H. pluvialis was conducted by photoautotrophic culture in the $CO_2$ supplemented photo-incubator. Maximum growth rate of H. pluvialis was obtained at a 5% $CO_2$ environment on basic N and P conditions of NIES-C medium. The photoautotrophic induction consisted of 5% $CO_2$ supply and high light illumination promoted astaxanthin synthesis in H. pluvialis, yielding an astaxanthin productivity of $9.6mg/L{\cdot}day$ and a $CO_2$ conversion rate of $27.8mg/L{\cdot}day$ to astaxanthin. From the results the sequential photoautotrophic culture and induction process using H. pluvialis is expecting an alternative $CO_2$ reduction technology with a function of valuable biosubstance production.

A Study on the Test and Installation Standards of the Video Fire Detector (영상화재감지기 시험과 설치기준에 관한 연구)

  • Lee, Jeong-Hyun;Baek, Dong-Hyun
    • Fire Science and Engineering
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    • v.30 no.4
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    • pp.1-5
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    • 2016
  • This research performed tests of Video Fire Detector and criteria of installation to make suggestions regarding the criteria that must be reflected in NFSC 203 by comparing the standards of FM Approvals, UL, ISO7240 and NFPA 72. FM Standard related to Video Fire Detector test has been classified as Smoke, Flame type, but the UL Standard has classified only as a Smoke type. This research examined 6 cases of fire phenomenon detection case in ISO 7240 and 3 cases in NFPA 72, respectively. There are 15 items required for the installation standard of a Video Fire Detector and each field standard is presented as a per installation method. To apply a Video Fire Detector, the pertinent items (the definition of term, detector's classification, structure and function among its test item) must be inserted. In addition, 7 items of the fire test, i.e., the sensitivity adjustment, prevent false alarm, ambient temperature test, the effective sensitivity and detection distance and viewing angle, aging test, flood test, must be applied to the actual test. For installation in the field, the operation environment and levels of illumination, and NFSC 203 must be set, and standards relevant to the sound system, indicators' installation distance, etc. need to be inserted.

Photodecomposition of Concentrated Ammonia over Nanometer-sized TiO2, V-TiO2, and Pt/V-TiO2 Photocatalysts

  • Choi, Hyung-Joo;Kim, Jun-Sik;Kang, Mi-Sook
    • Bulletin of the Korean Chemical Society
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    • v.28 no.4
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    • pp.581-588
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    • 2007
  • To enhance the photodecomposition of concentrated ammonia into N2, Pt/V-TiO2 photocatalysts were prepared using solvothermal and impregnation methods. Nanometer-sized particles of 0.1, 0.5 and 1.0 mol% V-TiO2 were prepared solvothermally, and then impregnated with 1.0 wt% Pt. The X-ray diffraction (XRD) peaks assigned to V2O5 at 30.20 (010) and Pt metal at 39.80 (111) and 46.20 (200) were seen in the 1.0 wt% Pt/ 10.0 mol% V-TiO2. The particle size increased in the order: pure TiO2, V-TiO2 and Pt/V-TiO2 after thermal treatment at 500 °C, while their surface areas were in the reverse order. On X-ray photoelectron spectroscopy (XPS), the bands assigned to the Ti2p3/2 and Ti2p1/2 of Ti4+-O were seen in all the photocatalysts, and the binding energies increased in the order: TiO2 < Pt/V-TiO2 < V-TiO2. The XPS bands assigned to the V2p3/2 (517.85, 519.35, and 520.55 eV) and V2p1/2 (524.90 eV) in the V3+, V4+ and V5+ oxides appeared over V-TiO2, respectively, while the band shifted to a lower binding energy with Pt impregnation. The Pt components of Pt/ V-TiO2 were identified at 71.60, 73.80, 75.00 and 76.90 eV, which were assigned to metallic Pt 4f7/2, PtO 4f7/2, PtO2 4f7/2, and PtO 4f5/2, respectively. The UV-visible absorption band shifted closer towards the visible region of the spectrum in V-TiO2 than in pure TiO2 and; surprisingly, the Pt/V-TiO2 absorbed at all wavelengths from 200 to 800 nm. The addition of vanadium generated a new acid site in the framework of TiO2, and the medium acidic site increased with Pt impregnation. The NH3 decomposition increased with the amount of vanadium compared to pure TiO2, and was enhanced with Pt impregnation. NH3 decomposition of 100% was attained over 1.0 wt% Pt/1.0 mol% V-TiO2 after 80 min under illumination with 365 nm light, although about 10% of the ammonia was converted into undesirable NO2 and NO. Various intermediates, such as NO2, -NH2, -NH and NO, were also identified in the Fourier transform infrared (FT-IR) spectra. From the gas chromatography (GC), FT-IR and GC/mass spectroscopy (GC/MS) analyses, partially oxidized NO and NO2 were found to predominate over V-TiO2 and pure TiO2, respectively, while both molecules were reduced over Pt/V-TiO2.

Study on Sensitivity of Variables of the Experiment to Evaluate Discomfort Glare of Interior Artificial Illumination (건축실내 인공조명의 불쾌글레어 평가실험에 적용된 실험변수의 민감도 분석에 관한 연구)

  • Lee, Jin-Sook;Kim, Won-Do;Kim, Chang-Soon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.1
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    • pp.24-32
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    • 2008
  • The ultimate purpose of the study is to develop a discomfort glare forecasting formula that can be practically used in Korea in order to effectively forecast discomfort glare considering the optical characteristics of the Koreans. The study was to examine the relations between discomfort glare and the variables such as luminance, background luminance, solid angle, luminous area and louver. To this end, experiments were conducted in a mock-up office that emulates the lighting environment of an ordinary office. The study was conducted by four steps as follow. First, previous studies on discomfort glare rating to define and rate discomfort glare were analyzed and modified to be applied to the experiments of this study. Second, experiment variables, variable scope, evaluation objects and evaluation points were determined after review on existing discomfort glare evaluation experimental formulas. Third, experiments were conducted in a mock-up office to be able to control variables. Finally, sensitivity of experiment variables were analyzed through examination of the relation between discomfort glare and the variables such as luminance, solid angle, louver, luminous area and subject's position. The result showed that the most influential variables on discomfort glare of an artificial light source is luminance and louver, luminous area and subject's position(solid angle) followed.

Occurrence Monitoring and Population Growth of Tomato Russet Mite, Aculops lycopersici Massee (Acari: Eriophyidae) Using Green Label Sticker (시설토마토에서 녹색 라벨 스티커를 이용한 토마토녹응애의 발생예찰과 개체군 생장)

  • Choi, Yong Seok;Nam, Yun Gyu;Whang, In Su;Park, Hong Hyun;Kim, Hyeong Hwan;Park, Deok Gee
    • Korean journal of applied entomology
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    • v.51 no.4
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    • pp.405-410
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    • 2012
  • This study is conducted to develop a new method of early occurrence monitoring for Aculops lycopersici Massee (Acari: Eriophyidae), a major pest in tomato. A. lycopersici causes damage to plants such as curling of leaflet edges, followed by leaflet bronzing. As feeding continues by the mites, the plant takes on a russeted, wilted appearance, eventually culminating in leaflet desiccation and finally plant death. Fruit damages in tomato were shown when the density of mites was very high. Also, A. lycopersici caused more damage to unripe fruits than ripe fruits. The time taken to detect A. lycopersici on green label sticker was 7.0 seconds, the shortest. Blue, orange and white label stickers took 17.1, 19.8 and 12.3 seconds respectively. The permeable microscope with side illumination was useful in observing A. lycopersici on label stickers. A. lycopersici began to occur in late-April and the density of the mites increased rapidly after mid-May. The density peaked in mid to late-June, and decreased after late-June. A. lycopersici was observed on lower stems 20 days after the release of mites and observed on higher stems 60 days after. The peaked densities were observed on stems 40 and 60 days after and on leaf 80 days after. The label sticker is enough to monitor early occurrence of A. lycopersici in tomato cultivation facilities.

KrF 엑시머 레이저를 이용한 웨이퍼 스텝퍼의 제작 및 성능분석

  • 이종현;최부연;김도훈;장원익;이용일;이진효
    • Korean Journal of Optics and Photonics
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    • v.4 no.1
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    • pp.15-21
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    • 1993
  • This paper describes the design and development of a KrF excimer laser stepper and discusses the detailed system parameters and characterization data obtained from the performance test. We have developed a deep UV step-and-repeat system, operating at 248 nm, by retrofitting a commercial modules such as KrF excimer laser, precision wafer stage and fused silica illumination and 5X projection optics of numerical aperture 0.42. What we have developed, to the basic structure, are wafer alignment optics, reticle alignment system, autofocusing/leveling mechanisms and environment chamber. Finally, all these subsystem were integrated under the control of microprocessor-based controllers and computer. The wafer alignment system comprises the OFF-AXIS and the TTL alignment. The OFF-AXIS alignment system was realized with two kinds of optics. One is the magnification system with the image processing technique and the other is He-Ne laser diffraction type system using the alignment grating on the wafer. 'The TTL alignment system employs a dual beam inteferometric method, which takes advantages of higher diffraction efficiency compared with other TTL type alignment systems. As the results, alignment accuracy for OFF-AXIS and TTL alignment system were obtained within 0.1 $\mu\textrm{m}$/ 3 $\sigma$ for the various substrate on the wafers. The wafer focusing and leveling system is modified version of the conventional systems using position sensitive detectors (PSD). This type of detection method showed focusing and leveling accuracies of about $\pm$ 0.1 $\mu\textrm{m}$ and $\pm$ 0.5 arcsec, respectively. From the CD measurement, we obtained 0.4 $\mu\textrm{m}$ resolution features over the full field with routine use, and 0.3 $\mu\textrm{m}$ resolution was attainable under more strict conditions.

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VLC Based Positioning Scheme in Vehicle-to-Infra(V2I) Environment (차량-인프라간 가시광 통신 기반 측위 기술)

  • Kim, Byung Wook;Song, Deok-Weon;Lee, Ji-Hwan;Jung, Sung-Yoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.3
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    • pp.588-594
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    • 2015
  • Although GPS technology for location positioning system has been widely used, it is difficult to be used in intelligent transport systems, due to the large positioning error and limited area for receiving radio signals. Thanks to the rapid development of LED technology, LED lights become popular in many applications. Especially, visible light communications (VLC) has raised a lot of interests because of the simultaneous functioning of LED illumination and communication. Recent studies on positioning system using VLC mainly focused on indoor environments and still difficult to satisfy positioning accuracy and simple implementation simultaneously. In this paper, we propose a positioning system based on VLC using the coordinate information of LEDs installed on the road infrastructure. Extracting the LED signal, obtained through VLC, from the easily accessible camera image, it is possible to estimate the position of the car on the road. Simulation results show that the proposed scheme can achieve a high positioning accuracy of 1 m when large number of pixels is utilized and the distance from the LED light is close.