• Title/Summary/Keyword: pixel density

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A Dust Detection Sensor System for Improvement of a Robot Vacuum Cleaner (청소 로봇 성능 향상을 위한 먼지 검출 시스템)

  • Kim, Dong-Hoe;Min, Byung-Cheol;Kim, Donghan
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.10
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    • pp.896-900
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    • 2013
  • In this paper, we develop a dust detection sensor system capable of identifying types of dust for an improvement of a robot vacuum cleaner. The dust detection sensor system is composed of a set of infra-red sensors: a single transmitter and multiple receivers. Given the fixed amount of light transmitted from the transmitter, the amount of light coming in multiple receiver sensors varies, depending on the type and density of dust that is passing between the transmitter and the receivers. Therefore, the type of dust can be identified by means of observing the change of the amount of light from the receiver sensors. For experiments, we use two types of dust, rice and sesame, and validate the effectiveness of the proposed method.

Block based Normalized Numeric Image Descriptor (블록기반 정규화 된 이미지 수 표현자)

  • Park, Yu-Yung;Cho, Sang-Bock;Lee, Jong-Hwa
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.49 no.2
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    • pp.61-68
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    • 2012
  • This paper describes a normalized numeric image descriptor used to assess the luminance and contrast of the image. The proposed image descriptor used the each pixel data as weighted value of the probability density function (PDF) and defined by normalization in order to objective represent. The proposed image numeric descriptor can be used to the adaptive gamma process because it suggests the objective basis of the gamma value selection.

Detection of Microphytobenthos Using Spectral Unmixing Method in the Saemangeum Tidal Flat, Korea

  • Lee, Y.K.;Won, J.S.;Ryu, J.H.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.853-855
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    • 2003
  • Microphytobenthos that supply nutrients to the intertidal ecosystem play an important part as a primary producer. If we estimate distribution and density of microphytobenthos, we can possibly calculate a volume of primary product in the tidal flat and its effect to the intertidal ecosystem. To estimate the portion of microphytobenthos, we used a linear spectral unmixing (LSU) method. LSU is a tool for inference the proportions of the pure components (or end-members) in a mixed pixel. The selection of end-members is critical to LSU. The end-members can be selected either from spectral libraries built from field surveys or from a remotely sensed image. We compared the two approaches of end-member selection, and the preliminary results showed end-members from from spectral library are as effective as those from image itself.

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A Fiber Laser Spectrometer Demodulation of Fiber Bragg Grating Sensors for Measurement Linearity Enhancement

  • Kim, Hyunjin;Song, Minho
    • Journal of the Optical Society of Korea
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    • v.17 no.4
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    • pp.312-316
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    • 2013
  • A novel fiber-optic sensor system is suggested in which fiber Bragg grating sensors are demodulated by a wavelength-sweeping fiber laser source and a spectrometer. The spectrometer consists of a diffraction grating and a 512-pixel photo-diode array. The reflected Bragg wavelength information is transformed into spatial intensity distribution on the photo-diode array. The peak locations linearly correspond to the Bragg wavelengths, regardless of the nonlinearities in the wavelength tuning mechanism of the fiber laser. The high power density of the fiber laser enables obtaining high signal-to-noise ratio outputs. The improved demodulation characteristics were experimentally demonstrated with a fiber Bragg grating sensor array with 5 gratings. The sensor outputs were in much more linear fashion compared with the conventional tunable band-pass filter demodulation. Also it showed advantages in signal processing, due to the high level of photo-diode array signals, over the broadband light source system, especially in measurement of fast varying dynamic physical quantities.

Salt and Pepper Noise Removal using 2-Dimensional Spline Interpolation (2차원 스플라인 보간법을 이용한 Salt and Pepper 잡음 제거)

  • Kwon, Se-Ik;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.6
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    • pp.1167-1173
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    • 2017
  • As the society increasingly embraces the high - tech digital information age, the field of image processing becomes progressively more branched out and becoming an imperative field. However, image data is deteriorated due to various causes during transmission and salt and pepper noise is typical. Typical methods for removing salt and pepper noise include CWMF, SWMF, and A-TMF. However, existing methods are somewhat insufficient in their ability to remove noise in salt and pepper noise environments. Therefore, in this paper, after it is determined whether noise removal is needed, the following measures were taken. If the center pixel was non-noise, the original pixel was preserved, If it was noise, we proposed a two - dimensional spline interpolation method and a median filter depending on the noise density of the local mask. For the purpose of objective judgment, we compared the results with that of existing methods and used PSNR (peak signal to noise ratio) as a judgment criterion.

The Analysis of Drainage Time and Resolution of the Quasi-dynamic and Dynamic Wetness Index (배수시간과 격자크기와 반동력학적 또는 동력학적 습윤지수에 대한 연구)

  • Kim, Sang-Hyun;Han, Ji-Young;Lee, Ga-Young;Kim, Nam-Won
    • Journal of Korea Water Resources Association
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    • v.36 no.6
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    • pp.949-960
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    • 2003
  • The resolution issue of wetness index with relaxation of the steady state assumption is explored on the platform of Digital Elevation Model (DEM). The variabilities of the quasi-dynamic wetness index and the dynamic wetness index are discussed on the base of the spatial and statistical aspects depending upon resolutions of DEM and the drainage time. The organization patterns of the wetness index can be observed upon various drainage times and pixel size. The transient behaviour of wetness patterns of the Sulmachun watershed are shown in the relatively short drainage time. The statistical analysis of the quasi-dynamic and dynamic wetness analysis provide the convergence of analysis results to the steady state characteristics later than 10,000 hours drainage time. The probability density functions of the quasi-dynamic and the dynamic wetness index shows the existence of the threshold pixel size of DEM which provide stability and consistency in the computation result of these two wetness index.

Evaluation of Relative Emission of Image Plate by Using Relative Sensitivity in Computed Radiography System (컴퓨터 방사선영상시스템에서 비감도를 이용한 영상판의 상대적 발광량 평가)

  • Seoung, Youl-Hun
    • The Journal of the Korea Contents Association
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    • v.14 no.11
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    • pp.355-361
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    • 2014
  • The aim of the present study was to evaluate a relative emission of image plate (IP) in computed radiography (CR) system by using relative sensitivity in film/screen methods. The characteristic curve was obtained by using the uniform aluminum 11-step wedge penetrometer. X-ray exposure factors on radiographic digital image were 50 kVp, 10 mAs. We adjusted zero of all parameter of algorithms (MUSICA) so proximate to raw data and applied to 200 of exposure class. Modeling on relative emission of IP are used IP without fading time and IP after 4 hours, 8 hours, 12 hours, 24 hours in the respective storage after X-ray exposure. The results of this study showed that the sensitivity point density at the measuring of relative sensitivity in CR was suited pixel values of the 2000 easy to relatively measure the characteristic curve and when relative sensitivity is decreased, the amount of light emitted from the image signal for generating was also decreased. In conclusion, the proposed method of measurement of relative sensitivity can be utilized to evaluate the quantity of relative emission of IP in CR system.

Parallel Design and Implementation of Shot Boundary Detection Algorithm (샷 경계 탐지 알고리즘의 병렬 설계와 구현)

  • Lee, Joon-Goo;Kim, SeungHyun;You, Byoung-Moon;Hwang, DooSung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.2
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    • pp.76-84
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    • 2014
  • As the number of high-density videos increase, parallel processing approaches are necessary to process a large-scale of video data. When a processing method of video data requires thousands of simple operations, GPU-based parallel processing is preferred to CPU-based parallel processing by way of reducing the time and space complexities of a given computation problem. This paper studies the parallel design and implementation of a shot-boundary detection algorithm. The proposed shot-boundary detection algorithm uses pixel brightness comparisons and global histogram data among the blocks of frames, and the computation of these data is characterized with the high parallelism for the related operations. In order to maximize these operations in parallel, the computations of the pixel brightness and histogram are designed in parallel and implemented in NVIDIA GPU. The GPU-based shot detection method is tested with 10 videos from the set of videos in National Archive of Korea. In experiments, the detection rate is similar but the computation time is about 10 time faster to that of the CPU-based algorithm.

The Analysis of Hydrological Response Structure Based on Spatial Correlation of Extracted Geomorphic Variables by Using DEM (DEM에 의해 추출된 지형인자의 공간상관성을 기반으로 한 수문학적 응답구조의 해석)

  • Kim, Joo-Cheol;Choi, Yong-Joon;Kim, Jae-Han
    • Journal of Korean Society for Geospatial Information Science
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    • v.18 no.2
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    • pp.69-78
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    • 2010
  • The hydrological-geomorphic character is closely related with runoff in basin. A development of GIS greatly helps investigating about mechanism between theirs. We analyze local slope and hillslope length which are related with hydrological response. But variation of these geomorphic variables has very wide range at each pixel. So there's a limit as to use directly. Therefore we investigate a relation between hydrological response and distributed geomorphic variables according to statistical character of distributed map considering spatial correlation. As a result, the local slope affects peak discharge, and the hillslope length affects peak discharge and time, mean and variance of hydrological response. Henceforth these hydrological-geomorphic analyze methods can be improved that hydrology response is directly analogized with DEM data.

A Study on Edge Detection using Directional Mask in Impulse Noise Image (임펄스 잡음 영상에서 방향성 마스크를 이용한 에지 검출에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.15 no.4
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    • pp.135-140
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    • 2014
  • As the digital image devices are widely used, interests in the software- and the hardware-related image processing become higher and the image processing techniques are applied in various fields such as object recognition, object detection, fingerprint recognition, and etc. For the edge detections Sobel, Prewitt, Laplacian, Roberts and Canny detectors are used and these existing methods can excellently detect the edges of the images without noise. However, in the images corrupted by the impulse noise, these methods are insufficent in noise elimination characteristics, showing unsatisfactory edge detection. Therefore in this paper, in order to obtain excellent edge detection characteristics in the corrupted image by the impulse noise, an detection algorithm is porposed, which uses the central pixel of mask divided by four regions along the axis, calculates the estimated mask according to the representing pixel values in each regions, and detects the final edges by applying the estimates mask and the new directional one.