• Title/Summary/Keyword: Modified illumination

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Moving Object Detection Robust to Sudden illumination Change using Modified Texture Information (개선된 텍스쳐 정보를 이용한 갑작스러운 조명 변화에 강인한 이동 물체 탐지)

  • O, Yoe-Han;Chang, Hyung-Jin;Kim, Soo-Wan;Choi, Jin-Young
    • Proceedings of the KIEE Conference
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    • 2008.10b
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    • pp.268-269
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    • 2008
  • Moving object detection is a fundamental technique in visual surveillance. Robust technique to enhance performance of moving object detection is required for several bad conditions in real external circumtance. In case of sudden illumination change in outdoor condition, many objects are determined as moving object though they are not really moving, but just their illumination changes. This makes the detection result untrustworthy. In this paper, robust moving object detection to sudden illumination change using gaussian mixture background model and new texture information using background from the weighted sum of recent images is proposed.

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Preprocessing and Facial Feature Robust to Illumination Variations (조명변화에 강인한 전처리 및 얼굴특징)

  • Kim, Dong-Ju;Lee, Sang-Heon;Kim, Hyun-Duk
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.7
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    • pp.503-506
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    • 2013
  • In this paper, we propose the face recognition method combining the ECSP preprocessing technique which is modified version of previous CS-LBP and the illumination-robust D2D-PCA feature. The performance evaluation of proposed method was carried out using various binary pattern operators and feature extraction algorithms such as well-known PCA and 2D-PCA on the Yale B database. As a results, the proposed method showed the best recognition accuracy compared to different approaches, and we confirmed that the proposed approach is robust to illumination variation.

Influence of Illumination on Domain Switching and Photovoltaic Current in Poled $(Pb_{1x}La_x)TiO_3$ Freeoelectric Ceramics

  • Park, Si-Kyung;Park, Dong-Gu;Kim, Sung-Ryul
    • The Korean Journal of Ceramics
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    • v.6 no.3
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    • pp.267-271
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    • 2000
  • The influence of photoexcited nonequilibrium carriers on domain switching and photovoltaic current was investigated in two kinds of poled La-modified PbTiO$_3$ferroelectric ceramics, (Pb$_{0.85}$La$_{0.15}$)TiO$_3$and (Pb$_{0.76}$La$_{0.24}$)TiO$_3$, under illumination in the absence of external electric field. Both photovoltaic current and cumulative AE event counts increased with illumination time. The observed nonsteady-state photovoltaic current could be explained on the basis of the cycles of a series of physical events consisting the establishment of space charge field by photoexcited carriers trapped at the grain boundaries, the photoinduced domain switching, and the increase in the remanent polarization. An analysis of energy distribution of the observed AE signals also revealed that the space charge field in (Pb$_{0.85}$La$_{0.15}$)TiO$_3$allowed both 18$0^{\circ}C$ and 90$^{\circ}$domains to be switched during illumination.

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Design and Analysis of Illumination Optics for Image Uniformity in Omnidirectional Vision Inspection System for Screw Threads (나사산 전면검사 비전시스템의 영상 균일도 향상을 위한 조명 광학계 설계 및 해석)

  • Lee, Chang Hun;Lim, Yeong Eun;Park, Keun;Ra, Seung Woo
    • Journal of the Korean Society for Precision Engineering
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    • v.31 no.3
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    • pp.261-268
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    • 2014
  • Precision screws have a wide range of industrial applications such as electrical and automotive products. To produce screw threads with high precision, not only high precision manufacturing technology but also reliable measurement technology is required. Machine vision systems have been used in the automatic inspection of screw threads based on backlight illumination, which cannot detect defects on the thread surface. Recently, an omnidirectional inspection system for screw threads was developed to obtain $360^{\circ}$ images of screws, based on front light illumination. In this study, the illumination design for the omnidirectional inspection system was modified by adding a light shield to improve the image uniformity. Optical simulation for various shield designs was performed to analyze image uniformity of the obtained images. The simulation results were analyzed statistically using response surface method, from which optical performance of the omnidirectional inspection system could be optimized in terms of image quality and uniformity.

UV-assisted surface modification of polyethersulfone (PES) membrane using TiO2 nanoparticles

  • Singh, Shruti;Karwa, Vinay;Marathe, K.V.
    • Membrane and Water Treatment
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    • v.9 no.6
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    • pp.393-403
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    • 2018
  • In this research commercial polyethersulfone (PES) membrane was modified using $TiO_2$ nanoparticles (P-25 Degussa) and further irradiated using UV light to overcome the hydrophobicity and fouling nature of the membrane. Further the membranes were characterized using SEM and FTIR. Contact angle measurements study confirmed the hydrophilic tendency of the modified membrane by decreasing the contact angle from $73^{\circ}$ to $20.28^{\circ}$. The modified membranes showed higher flux and better anti-fouling properties as compared to the unmodified counterparts. The optimum conditions were found to be 0.5 wt% $TiO_2$ loading with 60 min membrane immersion and 10 min UV light illumination. The effect of different pH conditions of feed was analysed. Real wastewater filtration experiments also indicated better performance of modified membranes as opposed to neat PES membranes.

Robust Person Identification Using Optimal Reliability in Audio-Visual Information Fusion

  • Tariquzzaman, Md.;Kim, Jin-Young;Na, Seung-You;Choi, Seung-Ho
    • The Journal of the Acoustical Society of Korea
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    • v.28 no.3E
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    • pp.109-117
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    • 2009
  • Identity recognition in real environment with a reliable mode is a key issue in human computer interaction (HCI). In this paper, we present a robust person identification system considering score-based optimal reliability measure of audio-visual modalities. We propose an extension of the modified reliability function by introducing optimizing parameters for both of audio and visual modalities. For degradation of visual signals, we have applied JPEG compression to test images. In addition, for creating mismatch in between enrollment and test session, acoustic Babble noises and artificial illumination have been added to test audio and visual signals, respectively. Local PCA has been used on both modalities to reduce the dimension of feature vector. We have applied a swarm intelligence algorithm, i.e., particle swarm optimization for optimizing the modified convection function's optimizing parameters. The overall person identification experiments are performed using VidTimit DB. Experimental results show that our proposed optimal reliability measures have effectively enhanced the identification accuracy of 7.73% and 8.18% at different illumination direction to visual signal and consequent Babble noises to audio signal, respectively, in comparison with the best classifier system in the fusion system and maintained the modality reliability statistics in terms of its performance; it thus verified the consistency of the proposed extension.

Defect Detection Method using Human Visual System and MMTF (MMTF와 인간지각 특성을 이용한 결함성분 추출기법)

  • Huh, Kyung-Moo;Joo, Young-Bok
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.12
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    • pp.1094-1098
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    • 2013
  • AVI (Automatic Vision Inspection) systems automatically detect defect features and measure their sizes via camera vision. Defect detection is not an easy process because of noises from various sources and optical distortion. In this paper the acquired images from a TFT panel are enhanced with the adoption of an HVS (Human Visual System). A human visual system is more sensitive on the defect area than the illumination components because it has greater sensitivity to variations of intensity. In this paper we modified an MTF (Modulation Transfer Function) in the Wavelet domain and utilized the characteristics of an HVS. The proposed algorithm flattens the inner illumination components while preserving the defect information intact.

Image Enhancement for Visual SLAM in Low Illumination (저조도 환경에서 Visual SLAM을 위한 이미지 개선 방법)

  • Donggil You;Jihoon Jung;Hyeongjun Jeon;Changwan Han;Ilwoo Park;Junghyun Oh
    • The Journal of Korea Robotics Society
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    • v.18 no.1
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    • pp.66-71
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    • 2023
  • As cameras have become primary sensors for mobile robots, vision based Simultaneous Localization and Mapping (SLAM) has achieved impressive results with the recent development of computer vision and deep learning. However, vision information has a disadvantage in that a lot of information disappears in a low-light environment. To overcome the problem, we propose an image enhancement method to perform visual SLAM in a low-light environment. Using the deep generative adversarial models and modified gamma correction, the quality of low-light images were improved. The proposed method is less sharp than the existing method, but it can be applied to ORB-SLAM in real time by dramatically reducing the amount of computation. The experimental results were able to prove the validity of the proposed method by applying to public Dataset TUM and VIVID++.

Studies on the modified dark incubation (암최청에 대한 연구)

  • 김윤식
    • Journal of Sericultural and Entomological Science
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    • v.10
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    • pp.59-62
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    • 1969
  • It is very important physiological and economical problems to hatching within a day by increasing hatching-ratio of silkworm eggs in sericulture, and modified dark incubating method was experimented in Japan. The author studied on the economical problems of that rather than physiological study. Hatching was induced and accelerated by illumination before hatching 5 days which incubated in the dark room after eye spot pigmented eggs emerged 10-20 percentage. It was increased by 80-90% in hatching-ratio, but the hatching was delayed a day. In autumn silkworm, newly hatched silkworms were hatched silkworms were hatched in the dark room because of high temperature period tough modified dark incubation was passed only 4 days. The author wonder which is more effective between effect of increasing the hatching-ratio and the health of silkworms.

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Design and Implementation of Real-time High Performance Face Detection Engine (고성능 실시간 얼굴 검출 엔진의 설계 및 구현)

  • Han, Dong-Il;Cho, Hyun-Jong;Choi, Jong-Ho;Cho, Jae-Il
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.2
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    • pp.33-44
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    • 2010
  • This paper propose the structure of real-time face detection hardware architecture for robot vision processing applications. The proposed architecture is robust against illumination changes and operates at no less than 60 frames per second. It uses Modified Census Transform to obtain face characteristics robust against illumination changes. And the AdaBoost algorithm is adopted to learn and generate the characteristics of the face data, and finally detected the face using this data. This paper describes the face detection hardware structure composed of Memory Interface, Image Scaler, MCT Generator, Candidate Detector, Confidence Comparator, Position Resizer, Data Grouper, and Detected Result Display, and verification Result of Hardware Implementation with using Virtex5 LX330 FPGA of Xilinx. Verification result with using the images from a camera showed that maximum 32 faces per one frame can be detected at the speed of maximum 149 frame per second.