• Title/Summary/Keyword: image analysis algorithm

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Segmentation of Multispectral MRI Using Fuzzy Clustering (퍼지 클러스터링을 이용한 다중 스펙트럼 자기공명영상의 분할)

  • 윤옥경;김현순;곽동민;김범수;김동휘;변우목;박길흠
    • Journal of Biomedical Engineering Research
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    • v.21 no.4
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    • pp.333-338
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    • 2000
  • In this paper, an automated segmentation algorithm is proposed for MR brain images using T1-weighted, T2-weighted, and PD images complementarily. The proposed segmentation algorithm is composed of 3 step. In the first step, cerebrum images are extracted by putting a cerebrum mask upon the three input images. In the second step, outstanding clusters that represent inner tissues of the cerebrum are chosen among 3-dimensional(3D) clusters. 3D clusters are determined by intersecting densely distributed parts of 2D histogram in the 3D space formed with three optimal scale images. Optimal scale image is made up of applying scale space filtering to each 2D histogram and searching graph structure. Optimal scale image best describes the shape of densely distributed parts of pixels in 2D histogram and searching graph structure. Optimal scale image best describes the shape of densely distributed parts of pixels in 2D histogram. In the final step, cerebrum images are segmented using FCM algorithm with its initial centroid value as the outstanding clusters centroid value. The proposed cluster's centroid accurately. And also can get better segmentation results from the proposed segmentation algorithm with multi spectral analysis than the method of single spectral analysis.

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Welding Bead Detection Inspection Using the Brightness Value of Vertical and Horizontal Direction (수직 및 수평 방향의 밝깃값을 이용한 용접 비드 검출 검사)

  • Jae Eun Lee;Jong-Nam Kim
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.4
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    • pp.241-248
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    • 2022
  • Shear Reinforcement of Dual Anchorage(SRD) is used to reinforce the safety of reinforced concrete structures at construction sites. Welding is used to make shear reinforcement, and welding plays an important role in determining productivity and competitiveness of products. Therefore, a weld bead detection inspection is required. In this paper, we suggest an algorithm for inspecting welding beads using image data of welding beads. First, the proposed algorithm calculates a brightness value in a vertical direction in an image, and then divides a welding bead in a vertical direction by finding a position corresponding to a 50% height point of the brightness value distribution in the image. The welding bead area is also divided in the same way for the horizontal direction, and then the segmentation image is analyzed if there is a welding bead. The proposed algorithm reduced the amount of computation by performing analysis after specifying the region of interest. In addition, accuracy could be improved by using all brightness values in the vertical and horizontal directions using the difference of brightness between the base metal and the welding bead region in the SRD image. The experiment compared the analysis results using five algorithms, such as K-mean and K-neighborhood, as a method to detect if there is a welding bead, and the experimental result proved that the proposed algorithm was the most accurate.

Development of RVE Reconstruction Algorithm for SMC Multiscale Modeling (SMC 복합재료 멀티스케일 모델링을 위한 RVE 재구성 알고리즘 개발)

  • Lim, Hyoung Jun;Choi, Ho-Il;Yoon, Sang Jae;Lim, Sang Won;Choi, Chi Hoon;Yun, Gun Jin
    • Composites Research
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    • v.34 no.1
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    • pp.70-75
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    • 2021
  • This paper presents a novel algorithm to reconstruct meso-scale representative volume elements (RVE), referring to experimentally observed features of Sheet Molding Compound (SMC) composites. Predicting anisotropic mechanical properties of SMC composites is challenging in the multiscale virtual test using finite element (FE) models. To this end, an SMC RVE modeler consisting of a series of image processing techniques, the novel reconstruction algorithm, and a FE mesh generator for the SMC composites are developed. First, micro-CT image processing is conducted to estimate probabilistic distributions of two critical features, such as fiber chip orientation and distribution that are highly related to mechanical performance. Second, a reconstruction algorithm for 3D fiber chip packing is developed in consideration of the overlapping effect between fiber chips. Third, the macro-scale behavior of the SMC is predicted by the multiscale analysis.

Determination of Road Image Quality Using Fuzzy-Neural Network (퍼지신경망을 이용한 도로 영상의 양불량 판정)

  • 이운근;백광렬;이준웅
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.6
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    • pp.468-476
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    • 2002
  • The confidence of information from image processing depends on the original image quality. Enhancing the confidence by an algorithm has an essential limitation. Especially, road images are exposed to lots of noisy sources, which makes image processing difficult. We, in this paper, propose a FNN (fuzzy-neural network) capable oi deciding the quality of a road image prior to extracting lane-related information. According to the decision by the FNN, road images are classified into good or bad to extract lane-related information. A CDF (cumulative distribution function), a function of edge histogram, is utilized to construct input parameters of the FNN, it is based on the fact that the shape of the CDF and the image quality has large correlation. Input pattern vector to the FNN consists of ten parameters in which nine parameters are from the CDF and the other one is from intensity distribution of raw image. Correlation analysis shows that each parameter represents the image quality well. According to the experimental results, the proposed FNN system was quite successful. We carried out simulations with real images taken by various lighting and weather conditions and achieved about 99% successful decision-making.

Analyzing Refractory Bricks of Ladles using Infrared Images (열화상 영상을 이용한 래들의 내화물 열화도 분석)

  • Lee, Sang Jun;Jeon, Yong-Ju;Kim, Sang Woo
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.4
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    • pp.291-300
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    • 2015
  • In the steel manufacturing process heat-endurance deterioration of a ladle used to cause a big accident. In this paper, an infrared imaging system and image analyzing procedure are proposed for inspecting refractory bricks of a ladle. The proposed algorithm contains following three parts: two-stage image selection procedure, reference point detection, and analysis of heat-endurance deterioration. Experiments were conducted with real data from a steel plant and detailed configuration of infrared imaging system was presented.

GEOLOGICAL LINEAMENTS ANALYSIS BY IFSAR IMAGES

  • Wu Tzong-Dar;Chang Li Chi
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.169-172
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    • 2005
  • Modem SAR interferometry (IFSAR) sensors delivering intensity images and corresponding digital terrain model (DTM) allow for a thorough surface lineament interpretation with the all-weather day-night applicability. In this paper, an automatic linear-feature detection algorithm for high-resolution SAR images acquired in Taiwan is proposed. Methodologies to extract linear features consist of several stages. First, the image denoising techniques are used to remove the speckle noise on the raw image. In this stage, the Lee filter has been chosen because of its superior performance. After denoising, the Coefficient of Variation Detector is performed on the result images for edge enhancements and detection. Dilation and erosion techniques are used to reconnect the fragmented lines. The Hough transform, which is a special case of a more general transform known as Radon transform, is a suitable method for line detection in our analysis. Finally, linear features are extracted from the binary edge image. The last stage contains many substeps such as edge thinning and curve pruning.

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Analysis for Location of Reinforcing Bars and Detection of Shape of Voids in Concrete Structures using Electromagnetic Radar (전자파 레이더법에 의한 콘크리트 내 철근위치 및 공동형상 해석에 관한 연구)

  • 박석균
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2003.04a
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    • pp.471-476
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    • 2003
  • The presence of voids under pavements or behind tunnel linings results in their deterioration. To detect these voids effectively by non-destructive tests, a method using radar was proposed. In this research, not only the detection of shape of voids, but also the location of reinforcing bars by radar image analysis is investigated. The experiments and image processing were conducted to detect voids and to locate reinforcing bars in or under concrete pavements (or tunnel linings) with reinforcing bars. From the results, the fundamental algorithm for tracing the reinforcing bars and voids, improving the horizontal resolution of the object image and detecting shape of objects, was verified.

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A Study on the Voxel Mesh Technique for Finite Element Modeling of Human Bone (인체 골(bone)의 유한요소 모델링을 위한 VOXEL MESH 기법에 관한 연구)

  • 변창환;오택열;백승민;채경덕
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.1081-1084
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    • 2002
  • In this study, we perform 3-D reconstruction of human proximal femur from DICOM files by using voxel mesh algorithm. After 3-D reconstruction, the model converted to Finite Element model which developed for automatically making not only 3-D geometrical model but also FE model from medical image dataset. During this job, trabecular pattern, one of characteristic of human bone can be added to the model by means of giving it's own elastic property calculated from intensity in CT scanned image to the each voxel. And then another model is made from same image dataset which have two material properties - one corresponds to cortical bone, another to trabecular bone. Finally, validity of voxel mesh technique is verified through comparing results of FE analysis, free vibration and stress analysis.

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Development of Radial Fin Static Mixers for Emulsion Oil (이멀션유용 방사상 핀 정적믹서 개발)

  • 김기성;박상규
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.4
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    • pp.904-911
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    • 2001
  • The fuels of water-in-oil emulsion have a potential of reducing PM(Particulate Matter) and NOx emissions, and increasing combustion efficiency in the furnaces and the burners. For making the most of the beneficial of the secondary atomization due to the microexplosion, the water droplets distributed in the oil must have the optimal sizes. The purpose of this paper is to investigate the water droplet size distribution characteristics of the different types of the static mixers. For analysis the size distribution characteristics efficiently, image analysis system wes constructed and an appropriate image processing algorithm was developed. Two kinds of static mixers: Kenics type and RF type, were tested. As a results, RF type static mixer shows a better characteristics in the mean drop size, particularly in the condition of high water content.

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An Effective Steel Plate Detection Using Eigenvalue Analysis (고유값 분석을 이용한 효과적인 후판 인식)

  • Park, Sang-Hyun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.7 no.5
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    • pp.1033-1039
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    • 2012
  • In this paper, a simple and robust algorithm is proposed for detecting each steel plate from a image which contains several steel plates. Steel plate is characterized by line edge, so line detection is a fundamental task for analyzing and understanding of steel plate images. To detect the line edge, the proposed algorithm uses the small eigenvalue analysis. The proposed approach scans an input edge image from the top left corner to the bottom right corner with a moving mask. A covariance matrix of a set of edge pixels over a connected region within the mask is determined and then the statistical and geometrical properties of the small eigenvalue of the matrix are explored for the purpose of straight line detection. Using the detected line edges, each plate is determined based on the directional information and the distance information of the line edges. The results of the experiments emphasize that the proposed algorithm detects each steel plate from a image effectively.