• Title/Summary/Keyword: background area

Search Result 2,615, Processing Time 0.032 seconds

Flaw Detection in Ceramics using Hough transform and Least squares

  • Hong, Dong-Jin;Cha, Eui-Young
    • Journal of the Korea Society of Computer and Information
    • /
    • v.20 no.10
    • /
    • pp.23-29
    • /
    • 2015
  • In this paper, we suggest a method of detecting defects by applying Hough transform and least squares on ceramic images obtained from non-destructive testing. In the ceramic images obtained from non-destructive testing, the background area, where the defect does not exist, commonly show gradual change of luminosity in vertical direction. In order to extract the background area which is going to be used in the detection of defects, Hough transform is performed to rotate the ceramic image in a way that the direction of overall luminosity change lies in the vertical direction as much as possible. Least squares are then applied on the rotated image to approximate the contrast value of the background area. The extracted background area is used for extracting defects from the ceramic images. In this paper we applied this method on ceramic images acquired from non-destructive testing. It was confirmed that extracted background area could be effectively applied for searching the section where the defect exists and detecting the defect.

A study on estimating background concentration of groundwater for water quality assessment in non-water supply district (상수도 미보급 지역의 지하수 수질상태 평가를 위한 배경농도 산정방법에 관한 연구)

  • Yea, Young-Do;Seo, Yong-Gyo;Kim, Rak-Hyeon;Cho, Dong-Jun;Kim, Kwang-Shik;Cho, Wook-Sang
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.28 no.3
    • /
    • pp.345-358
    • /
    • 2014
  • For introducing the groundwater quality assessment using background concentration of groundwater, several methods had been studied to estimate the background concentration of groundwater and to suggest the background concentration of study area. Some methods such as Box whisker plot, Percentile and Cumulative probability distribution had been adopted to estimate background concentration, and it was evaluated that the Cumulative probability distribution method presents more reasonable background concentration because it can consider the data distribution. So we estimated the background concentration of study area using cumulative probability distribution method. We suggested the background concentration for each hydrogeology respectively in case hydrogeological water quality similarity is very low.

Adaptive Zoom Motion Estimation Method (적응적 신축 움직임 추정 방법)

  • Jang, Won-Seok;Kwon, Oh-Jun;Kwon, Soon-Kak
    • Journal of Korea Multimedia Society
    • /
    • v.17 no.8
    • /
    • pp.915-922
    • /
    • 2014
  • We propose an adaptive zoom motion estimation method where a picture is divided into two areas based on the distance information with a depth camera : the one is object area and the other is background area. In the proposed method, the zoom motion is only applied to the object area except the background area. Further, the block size of motion estimation for the object area is set to smaller than that of background area. This adaptive zoom motion estimation method can be reduced at the complexity of motion estimation and can be improved at the motion estimation performance by reducing the block size of the object area in comparison with the conventional zoom motion estimation method. Based on the simulation results, the proposed method is compared with the conventional methods in terms of motion estimation accuracy and computational complexity.

Internal pressures in buildings with a dominant opening and background porosity

  • Kim, P.Y.;Ginger, J.D.
    • Wind and Structures
    • /
    • v.16 no.1
    • /
    • pp.47-60
    • /
    • 2013
  • A dominant opening in a windward wall, which generates large internal pressures in a building, is a critical structural design criterion. The internal pressure fluctuations are a function of the dominant opening area size, internal volume size and external pressure at the opening. In addition, many buildings have background leakage, which can attenuate internal pressure fluctuations. This study examines internal pressure in buildings for a range of dominant opening areas, internal volume sizes and background porosities. The effects of background porosity are incorporated into the governing equation. The ratio of the background leakage area $A_L$ to dominant opening area $A_W$ is presented in a non-dimensional format through a parameter, ${\phi}_6-A_L/A_W$. Background porosity was found to attenuate the internal pressure fluctuations when ${\phi}_6$ is larger than 0.2. The dominant opening discharge coefficient, ${\kappa}$ was estimated to lie between 0.05 to 0.40 and the effective background porosity discharge coefficient ${\kappa}^{\prime}_L$, was estimated to be between 0.05 to 0.50.

MSER-based Character detection using contrast differences in natural images (자연 이미지에서 명암차이를 이용한 MSER 기반의 문자 검출 기법)

  • Kim, Jun Hyeok;Lee, Sang Hun;Lee, Gang Seong;Kim, Ki Bong
    • Journal of the Korea Convergence Society
    • /
    • v.10 no.5
    • /
    • pp.27-34
    • /
    • 2019
  • In this paper, we propose a method to remove the background area by analyzing the pattern of the character area. In the character detection result of the MSER(Maximally Stable External Regions) method which distinguishes a region having a constant contrast background regions were detected. To solve this problem, we use the MSER method in natural images, the background is removed by calculating the change rate by searching the character area and the background area which are not different from the areas where the contrast values are different from each other. However, in the background removed image, using the LBP(Local Binary Patterns) method, the area with uniform values in the image was determined to be a character area and character detection was performed. Experiments were carried out with simple images with backgrounds, images with frontal characters, and images with slanted images. The proposed method has a high detection rate of 1.73% compared with the conventional MSER and MSER + LBP method.

Estimation of Surface Color with Use of Subjective Feeling: On the Influence of Contrast by Complementary Color

  • Sakamoto, Kazuyoshi;Wada, Mitsuyoshi;Min, Byung-Chan
    • Science of Emotion and Sensibility
    • /
    • v.5 no.2
    • /
    • pp.73-78
    • /
    • 2002
  • The unique colors of paper, that is, blue, green, red, and yellow were used in the estimation of color from the subjective feeling. The monochrome with unique color or the unique color surrounded with the background color was presented. subject gazed the monochrome or the unique color, which was tailed target rotor. The target and background color were the complementary color each other. The various ratios of the area of gazed color and background were taken. Subject answered the level of subjective feeling consisted of pair of adjective items for unique color presented. With the use of the subjective feeling for the target color presented, the estimation of the unique color was cai\ulcornerlied out due to Fuzzy theory and neural networks. The results of color difference between unique color presented and the estimated color gave very small value for the case without background, while the results of the case with background color depended on the ratio of area of presented color and background color till the ration of 2:1, The relation showed the Kirschman's law, The color difference saturated In the increase of area of background with the ratio more than 2:1.

  • PDF

Estimation of surface color with use of subjective feeling: On the influence of contrast by complementary color

  • Sakamoto, Kazuyoshi;Wada, Mitsuyoshi;Min, Byung-Chan
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
    • /
    • 2002.05a
    • /
    • pp.261-265
    • /
    • 2002
  • The unique colors of paper, that is, blue, green, red, and yellow were used in the estimation of color from the subjective feeling. The monochrome with unique color or the unique color surrounded with the background color was presented. Subject gazed the monochrome or the unique color, which was called target color. The target and background color were the complementary color each other. The various ratios of the area of gazed color and background were taken. Subject answered the level of subjective feeling consisted of pair of adjective items for unique color presented. With the use of the subjective feeling fer the target color presented, the estimation of the unique color was carried out due to Fuzzy theory and neural networks. The results of color difference between unique color presented and the estimated color gave very small value for the case without background, while the results of the case with background color depended on the ratio of area of presented color and background color till the ration of 2:1, The relation showed the Kirschman's law. The color difference saturated in the increase of area of background with the ratio more than 2:1.

  • PDF

The Study of Natural Background of Geologic Units for Stream Sediments in the Gurye Area (구례지역 하상퇴적물의 지질집단별 자연배경치에 대한 연구)

  • 박영석;장우석;김종균
    • Economic and Environmental Geology
    • /
    • v.36 no.4
    • /
    • pp.275-284
    • /
    • 2003
  • We collected the samples of stream sediments from primary channels in order to establish natural background of major and minor elements for geologic units in the Gurye area. Stream sediments samples having no possibility of contamination effect and representing drainage basins composed of uniform geology, were collected from April to May in 1999, the chemical analysis of which was carried out. The tolerable level was used to investigate the enrichment degree of harmful elements. The contents of Ni and Cr exceeded the tolerance level in some sections. The tolerance level excess of those elements was regarded as the effect of the metamorphic rock which constituted the bed rock of the area. In order to identify the comprehensive enrichment pattern, the tolerable level was used in calculating the enrichment index. The enrichment index of harmful heavy metals showed that Granite gneiss area is 0.39, Porphyroblastic granite gneiss area 0.32, Biotite gneiss area 0.42, Migmatitic gneiss area 0.41, Tuff area 0.30, Andesite area 0.46, Conglomerate area 0.42, and Granite area 0.26. Those results showed that natural background of Gurye area had not been exposed to harmful heavy metal elements.

A Segmentation Method for a Moving Object on A Static Complex Background Scene. (복잡한 배경에서 움직이는 물체의 영역분할에 관한 연구)

  • Park, Sang-Min;Kwon, Hui-Ung;Kim, Dong-Sung;Jeong, Kyu-Sik
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.48 no.3
    • /
    • pp.321-329
    • /
    • 1999
  • Moving Object segmentation extracts an interested moving object on a consecutive image frames, and has been used for factory automation, autonomous navigation, video surveillance, and VOP(Video Object Plane) detection in a MPEG-4 method. This paper proposes new segmentation method using difference images are calculated with three consecutive input image frames, and used to calculate both coarse object area(AI) and it's movement area(OI). An AI is extracted by removing background using background area projection(BAP). Missing parts in the AI is recovered with help of the OI. Boundary information of the OI confines missing parts of the object and gives inital curves for active contour optimization. The optimized contours in addition to the AI make the boundaries of the moving object. Experimental results of a fast moving object on a complex background scene are included.

  • PDF

A Study of Long-term Change in Carbon Dioxide Concentrations within and Across the Korean Peninsula between 1996 and 1997 (국내외 관측점간의 비교분석을 통한 이산화탄소의 장주기적 농도변화 특성에 관한)

  • 김기현;윤용훈;송기범
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.17 no.1
    • /
    • pp.105-115
    • /
    • 2001
  • This study was conducted to analyzed the pattern of $CO_2$ concentration changes in various time scale within and across the Korean Peninsula. We compared that data sets obtained from Moo-Ahn(NAN) station in Korea with those determined from major background observatory stations around the world from the periods of Aug. 1995 to Dec. 1997. The mean $CO_2$concentrations of the MAN area, if computed using the total of 884 daily mean values, were computed to by 374.5$\pm$6.6 ppm. When the background data for MAN were compared with those of other background site, the concentration of MAN was systematically higher than any other comparable sites. Results of correlation analysis between MAN and other background sites generally showed up the existence of strong correlations, indicating that the relative effect of $CO_2$ concentration change can proceed similarly over the globe. However, notable differences in annual growth rate of $CO_2$ between MAN and all the comparative sites suggested that its concentration in th MAN area be regulated in more complicated manners than those in the other areas. It is thus suspected that the data collected form MAN area be not effective enough to represent areal distribution characteristics of $CO_2$in the Korean Peninsula.

  • PDF