• Title/Summary/Keyword: Image Detector

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A Study on the Comparison of Detected Vein Images by NIR LED Quantity of Vein Detector (정맥검출기의 NIR LED 수량에 따른 검출된 정맥 이미지 비교에 관한 연구)

  • Jae-Hyun, Jo;Jin-Hyoung, Jeong;Seung-Hun, Kim;Sang-Sik, Lee
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.15 no.6
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    • pp.485-491
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    • 2022
  • Intravenous injection is the most frequent invasive treatment for inpatients and is widely used for parenteral nutrition administration and blood products, and more than 1 billion procedures are used for peripheral catheter insertion, blood collection, and other IV therapy per year. Intravenous injection is one of the difficult procedures to be performed only by trained nurses with intravenous injection training, and failure can lead to thrombosis and hematoma or nerve damage to the vein. Accordingly, studies on auxiliary equipment capable of visualizing the vein structure of the back of the hand or arm are being published to reduce errors during intravenous injection. This study is a study on the performance difference according to the number of LEDs irradiating the 850nm wavelength band on a vein detector that visualizes the vein during intravenous injection. Four LED PCBs were produced by attaching NIR filters to CCD and CMOS camera lenses irradiated on the skin to acquire images, sharpen the acquired images using image processing algorithms, and project the sharpened images onto the skin. After that, each PCB was attached to the front end of the vein detector to detect the vein image and create a performance comparison questionnaire based on the vein image obtained for performance evaluation. The survey was conducted on 20 nurses working at K Hospital.

HIGH RESOLUTION DELAY LINE READOUT ELECTRONOCS FOR THE TIME 2-D POSITION SENSITIVE DETECTOR (원자외선 분광기의 2차원 위치검출을 위한 고 분해능 지연선 검출회로)

  • 이진근;신종호;민경욱;남욱원;공경남
    • Journal of Astronomy and Space Sciences
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    • v.19 no.1
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    • pp.57-66
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    • 2002
  • We designed two-dimensional position sensitive MCP(mixt.ochannel plate) detector for FIMS, which is composed of MCP, delay line anode, and delay line readout elec-tronics. And also, we fabricated and tested for the operation stability and resolution of the delay line readout electronic system. An anode simulator and a stimulator were used instead of the real MCP and anode during the test to see the electronic contribution to the resolution. The readout electronics was operated stably and showed time resolution of about 560 ps for the spectral direction and about 100 ps for the image direction respectively.

Detection of Faces Located at a Long Range with Low-resolution Input Images for Mobile Robots (모바일 로봇을 위한 저해상도 영상에서의 원거리 얼굴 검출)

  • Kim, Do-Hyung;Yun, Woo-Han;Cho, Young-Jo;Lee, Jae-Jeon
    • The Journal of Korea Robotics Society
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    • v.4 no.4
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    • pp.257-264
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    • 2009
  • This paper proposes a novel face detection method that finds tiny faces located at a long range even with low-resolution input images captured by a mobile robot. The proposed approach can locate extremely small-sized face regions of $12{\times}12$ pixels. We solve a tiny face detection problem by organizing a system that consists of multiple detectors including a mean-shift color tracker, short- and long-rage face detectors, and an omega shape detector. The proposed method adopts the long-range face detector that is well trained enough to detect tiny faces at a long range, and limiting its operation to only within a search region that is automatically determined by the mean-shift color tracker and the omega shape detector. By focusing on limiting the face search region as much as possible, the proposed method can accurately detect tiny faces at a long distance even with a low-resolution image, and decrease false positives sharply. According to the experimental results on realistic databases, the performance of the proposed approach is at a sufficiently practical level for various robot applications such as face recognition of non-cooperative users, human-following, and gesture recognition for long-range interaction.

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Hand Raising Pose Detection in the Images of a Single Camera for Mobile Robot (주행 로봇을 위한 단일 카메라 영상에서 손든 자세 검출 알고리즘)

  • Kwon, Gi-Il
    • The Journal of Korea Robotics Society
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    • v.10 no.4
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    • pp.223-229
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    • 2015
  • This paper proposes a novel method for detection of hand raising poses from images acquired from a single camera attached to a mobile robot that navigates unknown dynamic environments. Due to unconstrained illumination, a high level of variance in human appearances and unpredictable backgrounds, detecting hand raising gestures from an image acquired from a camera attached to a mobile robot is very challenging. The proposed method first detects faces to determine the region of interest (ROI), and in this ROI, we detect hands by using a HOG-based hand detector. By using the color distribution of the face region, we evaluate each candidate in the detected hand region. To deal with cases of failure in face detection, we also use a HOG-based hand raising pose detector. Unlike other hand raising pose detector systems, we evaluate our algorithm with images acquired from the camera and images obtained from the Internet that contain unknown backgrounds and unconstrained illumination. The level of variance in hand raising poses in these images is very high. Our experiment results show that the proposed method robustly detects hand raising poses in complex backgrounds and unknown lighting conditions.

Spatial Compare Filter Based Real-Time dead Pixel Correction Method for Infrared Camera

  • Moon, Kil-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.12
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    • pp.35-41
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    • 2016
  • In this paper, we propose a new real-time dead pixel detection method based on spatial compare filtering, which are usually used in the small target detection. Actually, the soft dead and the small target are cast in the same mold. Our proposed method detect and remove the dead pixels as applying the spatial compare filtering, into the pixel outputs of a detector after the non-uniformity correction. Therefore, we proposed method can effectively detect and replace the dead pixels regardless of the non-uniformity correction performance. In infrared camera, there are usually many dead detector pixels which produce abnormal output caused by manufactural process or operational environment. There are two kind of dead pixel. one is hard dead pixel which electronically generate abnormal outputs and other is soft dead pixel which changed and generated abnormal outputs by the planning process. Infrared camera have to perform non-uniformity correction because of structural and material properties of infrared detector. The hard dead pixels whose offset values obtained by non-uniformity correction are much larger or smaller than the average can be detected easily as dead pixels. However, some dead pixels(soft dead pixel) can remain, because of the difficulty of uncleared decision whether normal pixel or abnormal pixel.

An Edge Detector by Using Perfect Sharpening of Ramps (램프의 완전 선명화를 이용한 에지 검출기)

  • Lee, Jong-Gu;Yoo, Cheol-Jung;Chang, Ok-Bae
    • Journal of KIISE:Software and Applications
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    • v.34 no.11
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    • pp.961-970
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    • 2007
  • Since the usual conventional edge detectors employ the local differential derivatives, the detected edges are not uniform in their widths or some edges are missed out of the detection on magnified images. We employ a mapping from the exactly monotonic intensity distributions of ramp edges to the simple step functions of intensity, which is referred to as perfect sharpening map of ramp edges. This map is based on the non-local feature of intensity distribution and used to introduce a modified differentiation, in terms of which we can construct an efficient edge detector adaptive to the variation of edge width. By adopting the operator MADD in this paper, we developed an edge detector that works stably against the magnification of image or the variation of edge width. It is shown by comparing to the conventional algorithms that the proposed one is very excellent.

CONSTRUCTION OF AN ENVIRONMENTAL RADON MONITORING SYSTEM USING CR-39 NUCLEAR TRACK DETECTORS

  • AHN GIL HOON;LEE JAI-KI
    • Nuclear Engineering and Technology
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    • v.37 no.4
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    • pp.395-400
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    • 2005
  • An environmental radon monitoring system, comprising a radon-cup, an etching system, and a track counting system, was constructed. The radon cup is a cylindrical chamber with a radius of 2.2 cm and a height of 3.2 cm in combination with a CR-39 detector. Carbon is impregnated in the bodies of the detector chamber to avoid problem of an electrostatic charge. The optimized etching condition for the CR-39 exposed to a radon environment turned out to be a 6 N NaOH solution at 70^{\circ}$ over a 7hour period. The bulk etch rate under the optimized condition was $1.14{\pm}0.03\;{\mu}m\;h^{-1}$. The diameter of the tracks caused by radon and its progeny were found to be in the range of $10\~25\;{\mu}m$ under the optimized condition. The track images were observed with a track counting system, which consisted of an optical microscope, a color charged couple device (CCD) camera, and an image processor. The calibration factor of this system is obtained to be $0.105{\pm}0.006$ tracks $cm^2$ per Bq $m^{-3}$ d.

Design and characterization of a Muon tomography system for spent nuclear fuel monitoring

  • Park, Chanwoo;Baek, Min Kyu;Kang, In-soo;Lee, Seongyeon;Chung, Heejun;Chung, Yong Hyun
    • Nuclear Engineering and Technology
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    • v.54 no.2
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    • pp.601-607
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    • 2022
  • In recent years, monitoring of spent nuclear fuel inside dry cask storage has become an important area of national security. Muon tomography is a useful method for monitoring spent nuclear fuel because it uses high energy muons that penetrate deep into the target material and provides a 3-D structure of the inner materials. We designed a muon tomography system consisting of four 2-D position sensitive detector and characterized and optimized the system parameters. Each detector, measuring 200 × 200 cm2, consists of a plastic scintillator, wavelength shifting (WLS) fibers and, SiPMs. The reconstructed image is obtained by extracting the intersection of the incoming and outgoing muon tracks using a Point-of-Closest-Approach (PoCA) algorithm. The Geant4 simulation was used to evaluate the performance of the muon tomography system and to optimize the design parameters including the pixel size of the muon detector, the field of view (FOV), and the distance between detectors. Based on the optimized design parameters, the spent fuel assemblies were modeled and the line profile was analyzed to conduct a feasibility study. Line profile analysis confirmed that muon tomography system can monitor nuclear spent fuel in dry storage container.

Four Segmentalized CBD Method Using Maximum Contrast Value to Improve Detection in the Presence of Reverberation (최대 컨트라스트 값을 이용한 4분할 CBD의 잔향 감소기법)

  • Choi, Jun-Hyeok;Yoon, Kyung-Sik;Lee, Soo-Hyung;Kwon, Bum-Soo;Lee, Kyun-Kyung
    • The Journal of the Acoustical Society of Korea
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    • v.28 no.8
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    • pp.761-767
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    • 2009
  • The detection of target echoes in a sonar image is usually difficult since reverberation is originated by the returns reflected around the boundary and volumes. Under the scenario of the target presence around the reverberation, the detection performance of existing algorithms is degraded. Since they have a similar statistical features. But proposed detector gives improvement existing algorithms Under this scenario. In this paper, 4 segmentation contrast box algorithm using maximum contrast value is proposed based on statistical segmentation, which gives better detection performance in the sense of reducing false alarms. The simulations validate the effectiveness of the proposed algorithm.

Correction of Single Photon Emission CT Image Distorted by Collimator Characteristic (시준기의 특성으로 인한 SPECT 왜곡 화상의 보정)

  • 백승권
    • Journal of the Institute of Convergence Signal Processing
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    • v.5 no.1
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    • pp.18-24
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    • 2004
  • SPECT technology is used for the reconstructed image in the field of industry noncontact measurement system. One of the distortion problems in reconstructed image quality is a collimator characterictic. The image distortion is caused by a geometrical structure of the collimator. This paper indicated a correction method to remove the image distortion by the structure of the collimator, and compared with the existing correction method. The correction. method removed the image distortion to use deconvolution of projection data with the shift-variant blurring function in the frequency domain. In this pater, I simulated with the collimator angle and distance between the detector and the center of object. and verified with expeimental data. The validity and limitation of correction method is studied for actual industrial applications.

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