• Title/Summary/Keyword: Geometric Data

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An Experimental Study on the Energy Separation in a Low Pressure Vortex Tube for Engine (기관적용 저압용 vortex tube의 에너지 분리특성에 관한 실험적 연구)

  • 오동진;임석연;윤면근;류정인
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.5
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    • pp.235-241
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    • 2002
  • The process of energy separation in a low pressure vortex tube with air as a working medium is studied In detail. Experimental data of the temperature of the cold and hot air leaving the vortex tube are presented. The variation of the maximum wall temperature along the inner surface of the vortex tube and the temperature distribution in the vortex tube provides useful information about the location of the stagnation point of the flow field at the axis of the vortex tube. In this study Outer tube is used for the application of Diesel engine exhaust. The hot gas flow is fumed 180° and passes the outside of the vortex tube a second time heating it. From this geometric setup of a vortex tube the effects of energy separation and the prediction of the ignition of Diesel Soot is presented by experimental data.

Edge Detection Method Based on Neural Networks for COMS MI Images

  • Lee, Jin-Ho;Park, Eun-Bin;Woo, Sun-Hee
    • Journal of Astronomy and Space Sciences
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    • v.33 no.4
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    • pp.313-318
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    • 2016
  • Communication, Ocean And Meteorological Satellite (COMS) Meteorological Imager (MI) images are processed for radiometric and geometric correction from raw image data. When intermediate image data are matched and compared with reference landmark images in the geometrical correction process, various techniques for edge detection can be applied. It is essential to have a precise and correct edged image in this process, since its matching with the reference is directly related to the accuracy of the ground station output images. An edge detection method based on neural networks is applied for the ground processing of MI images for obtaining sharp edges in the correct positions. The simulation results are analyzed and characterized by comparing them with the results of conventional methods, such as Sobel and Canny filters.

A Study on Winter-Covered Optical Satellite Imagery for Post-Eire Forest Monitoring

  • Kim, Choen;Park, Seung-Hwan
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.274-274
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    • 2002
  • Damage to forest trees, caused by wildfire, changes their spectral reflectance signature. This factor led to the initiation of a research project at the Remote Sensing & GIS Laboratory, Kookmin University, to determine if multispectral data acquired by IKONOS could provide fire scar and bum severity mapping. This paper will present detail mapping of burned areas in the eastern coast of Korea with IKONOS imagery. In addition, a single post-burn Landsat-7 ETM+ data was used to compare with IKONOS, the study area. Burn severity map based on IKONOS image was found to be affected by strong topographic illumination effects in the mountain forest. But it has better the delineation of the bum-scarred area. In this study the NDVI was analyzed for geometric illumination conditions influenced by topography(slop, aspect and elevation) and shadow(solar elevation and azimuth angle).

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3D City Modeling Using Laser Scan Data

  • Kim, Dong-Suk;Lee, Kwae-Hi
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.505-507
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    • 2003
  • This paper describes techniques for the automated creation of geometric 3D models of the urban area us ing two 2D laser scanners and aerial images. One of the laser scanners scans an environment horizontally and the other scans vertically. Horizontal scanner is used for position estimation and vertical scanner is used for building 3D model. Aerial image is used for registration with scan data. Those models can be used for virtual reality, tele-presence, digital cinematography, and urban planning applications. Results are shown with 3D point cloud in urban area.

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The Endmember Analysis for Sub-Pixel Detection Using the Hyperspectral Image

  • Kim, Dae-Sung;Cho, Young-Wook;Han, Dong-Yeob;Kim, Young-Il
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.732-734
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    • 2003
  • In the middle -resolution remote sensing, the Ground Sampled Distance(GSD) sensed and sampled by the detector is generally larger than the size of objects(or materials) of interest, in which case several objects are embedded in a single pixel and cannot be detected spatially. This study is intended to solve this problem of a hyperspectral data with high spectral resolution. We examined the detection algorithm, Linear Spectral Mixing Model, and also made a test on the Hyperion data. To find class Endmembers, we applied two methods, Spectral Library and Geometric Model, and compared them with each other.

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A study on global environmental monitoring by using ADEOS-II GLI data

  • Yamamoto, Hirokazu;Hashimoto, Toshiaki;Mitomi, Yasushi;Yoshioka, Hiroki;Honda, Yoshiaki;Igarashi, Tamotsu
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.482-484
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    • 2003
  • GLI on boarded ADEOS-II satellite allows us to observe vegetation status in the two different resolutions simultaneously, because of thirty 1km resolution channels and six 250m resolution channels. There are four GLI land higher level products from these channels ; those are PGCP (Precise Geometric Correction Parameter), L2A_LC (TOA reflectance), ACLC (atmospheric corrected reflectance), and VGI (NDVI and EVI). This paper shows ADEOS-II GLI land data processing, and some of the latest results.

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Particle tracking acceleration via signed distance fields in direct-accelerated geometry Monte Carlo

  • Shriwise, Patrick C.;Davis, Andrew;Jacobson, Lucas J.;Wilson, Paul P.H.
    • Nuclear Engineering and Technology
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    • v.49 no.6
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    • pp.1189-1198
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    • 2017
  • Computer-aided design (CAD)-based Monte Carlo radiation transport is of value to the nuclear engineering community for its ability to conduct transport on high-fidelity models of nuclear systems, but it is more computationally expensive than native geometry representations. This work describes the adaptation of a rendering data structure, the signed distance field, as a geometric query tool for accelerating CAD-based transport in the direct-accelerated geometry Monte Carlo toolkit. Demonstrations of its effectiveness are shown for several problems. The beginnings of a predictive model for the data structure's utilization based on various problem parameters is also introduced.

Assessment of Accuracy of IKONOS Image Map, Traditional Orthophoto Map and Conventional Line Map of Kathmandu Valley : A Pilot Study

  • Kayastha, D.M.;Chhatkuli, R.R.;Paudel, J.R.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.988-990
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    • 2003
  • IKONOS image mapping is being considered a possible replacement to the traditional mapping in many countries due to their ease of access to current data and their potential high resolution. Survey Department of His Majesty's Government completed traditional orthophoto mapping of all urban and semi-urban areas of the country. The 1:5000 monochrome orthophoto maps of Kathmandu Valley were completed in 2003. In 2002, as a test, production of a near natural colour Image Map at 1:5000 scale of a part of Kathmandu Valley based on IKONOS data was carried out. A conventional line map plotting of the same area at 1:5000 was also prepared. The objective of the pilot project was to assess the geometric accuracy and the information content of these maps. The details of the study and their results are underlined. The findings of the study helps to explain whether IKONOS image map can replace conventional orthophoto map at 1:5,000 for urban areas of Nepal like Kathmandu.

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Statistical Aspects and the Extimation Scheme of the Short Term Concentration of Air Pollution (大氣汚染濃度의 發生頻度特徵 및 推定法 評價)

  • Lee, Chog-Bum;Kang, In-Goo
    • Journal of Korean Society for Atmospheric Environment
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    • v.5 no.1
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    • pp.88-95
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    • 1989
  • The aspects of the occurence frequency of $SO_2$ concentration were studied with the observed data in Seoul and the scheme that is capable of estimating not only highest concentration for a variety of averaging times but also concentrations for arbitary occurrence frequency with long term arithmatic mean and geometric standard deviation data, was evaluated. The results of the statistical analysis show that the occurrence frequency is almost log normal except a few cases, and 3rd highest values of daily mean concentration were about 4.2 $\sim$ 5.2 times higher than annual arithmatic mean. The evaluation with the observed hourly concentration shows that the scheme fairly well estimate the short concentration of arbitary occurrence frequence and it can be used for air quality management and environmental impact assessment.

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Design and Implementation of Circular Dot Pattern Code (CDPC) and Its Recognition Algorithm which is robust to Geometric Distortion and Noise (대화형 인쇄물 구현을 위한 기하변형과 잡음에 강인한 원형 점 패턴코드의 설계와 인식 알고리즘 구현)

  • Shim, Jae-Youn;Kim, Seong-Whan
    • Proceedings of the Korea Information Processing Society Conference
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    • 2011.11a
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    • pp.1166-1169
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    • 2011
  • In this paper, we design a Circle dot Code, In our scheme, we design a dot patterns for increasing maximum capacity and also for increasing robustness to Affine Transformation. Our code Can be extended according number of data circle. We use three data circle vision code. In this type code, after acquiring camera images for the Circle dot Codes, and perform error correction decoding using four position symbols and six CRC symbols. We perform graph based dot code analysis which determines the topological distance between dot pixels. Our code can be bridged the real world and ubiquitous computing environment.