• Title/Summary/Keyword: Detection Space

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Effective Acne Detection using Component Image a* of CIE L*a*b* Color Space (CIE L*a*b* 칼라 공간의 성분 영상 a*을 이용한 효과적인 여드름 검출)

  • Park, Ki-Hong;Noh, Hui-Seong
    • Journal of Digital Contents Society
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    • v.19 no.7
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    • pp.1397-1403
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    • 2018
  • Today, modern people perceive skin care as part of their physical health care, and acne is a common skin disease problem that is found on the face. In this paper, an effective acne detection algorithm using CIE $L^*a^*b^*$ color space has been proposed. It is red when the pixel value of the component image $a^*$ is a positive number, so it is suitable for detecting acne in skin image. First, the skin image based on the RGB color space is subjected to light compensation through color balancing, and converted into a CIE $L^*a^*b^*$ color space. The extracted component image $a^*$ was normalized, and then the skin and acne area were estimated with the threshold values. Experimental results show that the proposed method detects acne more effectively than the conventional method based on brightness information, and the proposed method is robust against the reflected light source.

Study on MMTI Signal Processing Algorithm and Analysis of the Performance for Periscope Detection in Airborne Radar (항공용 레이다를 이용한 잠망경 탐지 MMTI 신호처리 기법 연구 및 성능 분석)

  • Jung, Jae-Hoon;Lee, Jae-Min;Youn, Jae-Hyuk;Shin, Hee-Sub
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.8
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    • pp.661-669
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    • 2017
  • This paper describes an MMTI(Maritime Moving Target Indicator) for periscope detection in airborne radar. Firstly, we analyze the characteristics of sea clutter, sea targets. Secondly, we study the differences between GMTI(Ground Moving Target Indicator) and MMTI. This paper proposes an optimal MMTI operating environment and method. We also suggest a signal processing algorithm using STAP(Space-Time Adaptive Processing) for detecting small RCS target moving low speed. The detection probability for moving target with MDV(Minimum Detectable Velocity) is simulated under various RCS and multi-channel system. Finally, we analyze the major performance for range, velocity and azimuth accuracy.

Searching for Dwarf Galaxies in deep images of NGC 1291 obtained with KMTNet

  • Byun, Woowon;Kim, Minjin;Sheen, Yun-Kyeong;Park, Hong Soo;Ho, Luis C.;Lee, Joon Hyeop;Jeong, Hyunjin;Kim, Sang Chul;Park, Byeong-Gon;Seon, Kwang-Il;Ko, Jongwan
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.80.2-80.2
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    • 2019
  • We present newly discovered dwarf galaxy candidates in deep wide-field images of NGC 1291 obtained with KMTNet. We initially identify 20 dwarf galaxy candidates through visual inspection. 13 out of 20 appears to be high priority candidates, according to their central surface brightness (${\mu}_{0,R}{\sim}22.5$ to $26.5mag\;arcsec^{-2}$) and effective radii (350 pc to 1 kpc). Structural and photometric properties of dwarf candidates appear to be consistent with those of ordinary dwarf galaxies in nearby groups and clusters. Using imaging simulations, we demonstrate that our imaging data is complete up to $26mag\;arcsec^{-2}$ with > 70% of the completeness rate. In order to find an optimal way to automate detecting dwarf galaxies in our dataset, we test detection methods by varying parameters in SExtractor. We find that the detection efficiency from the automated method is relatively low and the contamination due to the artifacts is non-negligible. Therefore, it can be only applicable for pre-selection. We plan to conduct the same analysis for deep images of other nearby galaxies obtained through KMTNet Nearby Galaxy Survey (KNGS).

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Improvement of the Double Fault Detection Performance of Extended Parity Space Approach (확장 패리티 공간 기법의 이중고장 검출성능 향상 연구)

  • Lee, Won-Hee;Park, Chan-Gook;Lee, Dal-Ho;Kim, Kwang-Hoon
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.10
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    • pp.1002-1008
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    • 2009
  • We consider a double faults detection and isolation problem using modified extended parity space approach for inertial measurement unit which use redundant inertial sensors. A redundant IMU which has a hardware redundant is composed of the cone shape because it is good for fault detection and isolation. We analyze the type of double faults and the reason why fault isolation performance is low. We propose modified extended parity space approach method using EPSA and the difference of sensor data.

Feature Point Detection and Tracking of Object in Motion Image on Internet (인터넷상의 동영상에서의 물체 특징 점 탐지 및 추적)

  • Im In Sun
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.1 s.33
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    • pp.149-156
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    • 2005
  • In the actuality that the various services are provided in connection with the network of internet by activating the communication using Propagation, the importance of the feature point and chase of an object is greatly raised to increase the quality of the detection and tracking of the communication service. This paper is to detect the shadow space by using Snakes Algorithms and Present a system's base which tracts the route from start to target points in the detected shadow space as a study for the detection and tracking the shadow space which does not reach the propagation.

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Single Logarithmic Amplification and Deep Learning-based Fixed-threshold On-off Keying Detection for Free-space Optical Communication

  • Qian-Wen Jing;Yan-Qing Hong
    • Current Optics and Photonics
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    • v.8 no.3
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    • pp.239-245
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    • 2024
  • This paper proposes single logarithmic amplification (single-LA) and deep learning (DL)-based fixed-threshold on-off keying (OOK) detection for free-space optical (FSO) communication. Multilevel LAs (MLAs) can be used to mitigate intensity fluctuations in the received OOK signal by their nonlinear gain characteristics; however, it is ineffective in the case of high scintillation, owing to degradation of the OOK signal's extinction ratio. Therefore, a DL technique is applied to realize effective scintillation compensation in single-LA applications. Fully connected (FC) networks and fully connected neural networks (FCNN), which have nonlinear modeling characteristics, are deployed in this work. The performance of the proposed method is evaluated through simulations under various scintillation effects. Simulation results show that the proposed method outperforms the conventional adaptive-threshold-decision, single-LA-based, MLA-based, FC-based, and FCNN-based OOK detection techniques.

C IV Emission-line Detection of the Supernova Remnant RCW 114

  • Kim, Il-Joong;Min, Kyoung-Wook;Seon, Kwang-Il;Han, Won-Young;Edelstein, Jerry
    • Bulletin of the Korean Space Science Society
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    • 2009.10a
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    • pp.33.3-33.3
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    • 2009
  • We report the detection of the C IV $\lambda\lambda1548$, 1551 emission line in the region of the RCW 114 nebula using the FIMS/SPEAR data. The observed C IV line intensity indicates that RCW 114 is much closer to us than HD 156385, a Wolf-Rayet star that was thought to be associated with RCW 114 in some of the previous studies. We also found the existence of a small H I bubble centered on HD 156385, with a different LSR velocity range from that of the large H I bubble which was identified previously as related to RCW 114. These findings imply that the RCW 114 nebula is an old supernova remnant which is not associated with the Wolf-Rayet star, HD 156385. Additionally, the global morphology of the C IV and $H{\alpha}$ emissions shows that RCW 114 has evolved in a non-uniform interstellar medium.

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Two-Faults Detection and Isolation Using Extended Parity Space Approach

  • Lee, Won-Hee;Kim, Kwang-Hoon;Park, Chan-Gook;Lee, Jang-Gyu
    • Journal of Electrical Engineering and Technology
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    • v.7 no.3
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    • pp.411-419
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    • 2012
  • This paper proposes a new FDI(Fault Detection and Isolation) method, which is called EPSA(Extended Parity Space Approach). This method is particularly suitable for fault detection and isolation of the system with one faulty sensor or two faulty sensors. In the system with two faulty sensors, the fault detection and isolation probability may be decreased when two faults are occurred between the sensors related to the large fault direction angle. Nonetheless, the previously suggested FDI methods to treat the two-faults problem do not consider the effect of the large fault direction angle. In order to solve this problem, this paper analyzes the effect of the large fault direction angle and proposes how to increase the fault detection and isolation probability. For the increase the detection probability, this paper additionally considers the fault type that is not detected because of the cancellation of the fault biases by the large fault direction angle. Also for the increase the isolation probability, this paper suggests the additional isolation procedure in case of two-faults. EPSA helps that the user can know the exact fault situation. The proposed FDI method is verified through Monte Carlo simulation.

3D Detection of Obstacle Distribution and Mapping for Walking Guide of the Blind (시각 장애인 보행안내를 위한 장애물 분포의 3차원 검출 및 맵핑)

  • Yoon, Myoung-Jong;Jeong, Gu-Young;Yu, Kee-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.2
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    • pp.155-162
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    • 2009
  • In walking guide robot, a guide vehicle detects an obstacle distribution in the walking space using range sensors, and generates a 3D grid map to map the obstacle information and the tactile display. And the obstacle information is transferred to a blind pedestrian using tactile feedback. Based on the obstacle information a user plans a walking route and controls the guide vehicle. The algorithm for 3D detection of an obstacle distribution and the method of mapping the generated obstacle map and the tactile display device are proposed in this paper. The experiment for the 3D detection of an obstacle distribution using ultrasonic sensors is performed and estimated. The experimental system consisted of ultrasonic sensors and control system. In the experiment, the detection of fixed obstacles on the ground, the moving obstacle, and the detection of down-step are performed. The performance for the 3D detection of an obstacle distribution and space mapping is verified through the experiment.

Real-time Smoke Detection Research with False Positive Reduction using Spatial and Temporal Features based on Faster R-CNN

  • Lee, Sang-Hoon;Lee, Yeung-Hak
    • Journal of IKEEE
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    • v.24 no.4
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    • pp.1148-1155
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    • 2020
  • Fire must be extinguished as quickly as possible because they cause a lot of economic loss and take away precious human lives. Especially, the detection of smoke, which tends to be found first in fire, is of great importance. Smoke detection based on image has many difficulties in algorithm research due to the irregular shape of smoke. In this study, we introduce a new real-time smoke detection algorithm that reduces the detection of false positives generated by irregular smoke shape based on faster r-cnn of factory-installed surveillance cameras. First, we compute the global frame similarity and mean squared error (MSE) to detect the movement of smoke from the input surveillance camera. Second, we use deep learning algorithm (Faster r-cnn) to extract deferred candidate regions. Third, the extracted candidate areas for acting are finally determined using space and temporal features as smoke area. In this study, we proposed a new algorithm using the space and temporal features of global and local frames, which are well-proposed object information, to reduce false positives based on deep learning techniques. The experimental results confirmed that the proposed algorithm has excellent performance by reducing false positives of about 99.0% while maintaining smoke detection performance.