• Title/Summary/Keyword: Image Deformation

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Change Analysis of Eulsukdo Wetland Using Qualitative Multi-temporal Image Data (다중시기 영상자료를 이용한 을숙도 습지 지역의 정성적 변화분석)

  • Lee, Jae-One;Kim, Yong-Suk;We, Gwang-Jae
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.2
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    • pp.64-73
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    • 2010
  • This research collected some multi-image information of Nakdong River Estuary Eulsukdo area in last 30 years, which are used as the basis information in running the qualitative analysis of the topography relief's deformation. First, to obtain the data, this research carried out a field survey and GCP measurement, then classified and collected the image information by analog and digital image. The acquired images which have passed a high-precise scan process and geometric correction is manufactured by Ortho Mosaic image, then divided them into 9 sections time period classification before we run a qualitative analysis. In late of 1980's there are many changes of environmental topography deformation of the Eulsukdo area which caused by large scale building constructions, appeared to be known through this research. And then in late of 1990's, we organized the wild cultivated lands, started the wetland restoration of the artificial ecology, in 2000's we are able to know the existence of topograph relief change which caused by big scale of bridge construction. Hereafter, in this quick process of the environmental and topographical change of this area caused by the 4 major rivers restoration project, the analysis results of this experiment are expected to be something applicable as important basic data.

2D Image Numerical Correction Method for 2D Digital Image Correlation (2차원 DIC 기법 적용을 위한 2D 이미지 보정 수치 해석 기법)

  • Kim, Wonseop;Hong, Seokmoo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.391-397
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    • 2017
  • Recently, digital image correlation (DIC) techniques have been used to measure dynamic deformation during tensile testing. The standard tensile test method measures the average displacement of the relevant specimen to calculate the true stress-strain curve. Therefore, the validity of the true stress curve is restricted to the stress incurred within the uniform stretching interval, i.e., the maximum stress corresponds to the starting point of the necking deformation. Alternatively, if DIC is used, the effective range of the strain and strain rate can be extended to the breaking point of the tensile specimen, because of the feasibility of measuring the local strain over the entire area of interest. Because of these advantages, many optical 3D measurement systems have been introduced and used in research and industry. However, the conventional 3D measurement systems are exceedingly expensive and time consuming. In addition, these systems have the disadvantage of a very large equipment size which makes their transport difficult. In this study, a 2D image correction method employing a 2D DIC measurement method in conjunction with a numerical analysis method is developed using a smartphone. The results of the proposed modified 2D DIC method yielded higher accuracy than that obtained via the 3D measurement equipment. In conclusion, it was demonstrated that the proposed 2D DIC and calibration methods yield accurate measurement results with low time costs.

Measurement of Soil Deformation around the Tip of Model Pile by Close-Range Photogrammetry (근접 사진측량에 의한 모형말뚝 선단부 주변의 지반 변형 측정)

  • Lee, Chang No;Oh, Jae Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.2
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    • pp.173-180
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    • 2013
  • In this paper, we studied on measurement of soil deformation around the tip of model pile by close-range photogrammetry. The rigorous bundle adjustment method was utilized to monitor the soil deformation in the laboratory model pile-load test as function of incremental penetration of the pile. Control points were installed on the frame of the laboratory model box case and more than 150 target points were inserted inside the soil around the model pile and on the surface. Four overlapping images including three horizontal and one vertical image were acquired by a non-metric camera for each penetration step. The images were processed to automatically locate the control and target points in the images for the self-calibration and the bundle adjustment. During the bundle adjustment, the refraction index of the acrylic case of the laboratory model was accounted for accurate measurement. The experiment showed the proposed approach enabled the automated photogrammetric monitoring of soil deformation around the tip of model pile.

A Research of Coastline Deformation with an Aerial Photo

  • Kim, Kam-Lae;Kim, Hak-Joon;Jeon, Ho-Won
    • Korean Journal of Geomatics
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    • v.3 no.1
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    • pp.1-6
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    • 2003
  • The purpose of this study is to make out a history of the coastline deformation with annual aerial photos of the target area and to suggest an efficient method for interpreting the coastline deformation. First, there were difficulties in obtaining annual aerial photos of an identical area as well as collecting periodical datum because of too much change of the real area during more than 27 years. Besides the past aerial photo is inferior to the latest one in quality. So there is nothing but to exclude an accuracy evaluation of the ortho photo. Taken into account the extent of the coastline change for 27 years is more than 10M and the all errors of the ortho image is included in this extent, both an accuracy and an error are ignored. The result of this study show that the coastline in the sea area of Namhangjin maintain advanced forward the ocean and keeps on moving with maintaining fairly wider shape of balance beach. Also The coastline deformation off l㎞ from the estuary is greatly irregular, which means the erosion of the sea in this area is in progress. The latest data being the aerial photo in 1996, it is difficult to find out the current conditions of a coastal erosion. However, considered the construction of a breakwater in Anmok Harbor is going on, the beach erosion becomes more accelerative recently. The aerial photos of the present Namhangjin's situation will make it possible to understand the history of the coastline change more accurately.

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A Study on the Micro-deformation of Plain Weave Carbon/Epoxy Composite-Polymer Foam Sandwich Structures during Curing (평직 탄소섬유 복합재료-고분자 포움 샌드위치 구조의 성형 중 미소변형에 관한 연구)

  • Kim Yong-Soo;Chang Seung-Hwan
    • Composites Research
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    • v.17 no.6
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    • pp.28-36
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    • 2004
  • Micro-tow deformation during forming of PVC foam-fabric composite sandwich structure is investigated to find out the correlation between forming condition and material deformation. The foams used in this research are PVC foams which have 4 different densities and the fabric composite is Carbon/epoxy prepreg which is plain weave (3k) as a skin material. Tow parameters such as crimp angle and tow amplitude are measured using microscope and a proper image tool and are compared with each other. In order to find out the effect of foam deformation during forming on tow deformation the compressive tests of foams are performed in three different environmental temperatures ($25^{\circ}C$, $80{\circ}C$, $125^{\circ}C$). The microscopic observation results show that the micro tow deformations are quite different from each other with respect to the foam density and forming pressure.

The Text Analysis of Plasticity Expressed in the Modern Art to Wear (Part II) - Focused on the West Art Works since 1980s - (현대 예술의상에 표현된 조형성의 텍스트 분석 (제2보) - 1980년대 이후 서구 작가 작품을 중심으로 -)

  • Seo, Seung-Mi;Yang, Sook-Hi
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.7 s.144
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    • pp.926-937
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    • 2005
  • The analysis category of Art to Wear was text analyzed from the research material of 100 projects put together by fashion specialist. The conclusion of Art to Wear was comprehended the general features of it were compared and analyzed from a semiotics context. According to this analysis, the formative features of modern Art to Wear is categorized into three different dimensions from a semiotics light. The formative features of modem Art to Wear in the light of syntactic dimension was divided as an open constructed shape of Space Extension, non-typical Deformation, Geometrical Plasticity. The formative features of modem Art to Wear in the light of semantic dimension express symbolic meaning through metaphorical sign. These sign reflect the body image of the life and death and its objective of Abjection, Hybrid of discultural appearance and the image of Hyper-reality, which are features used to comprehend the inner meaning. The formative features of modem Art to Wear in the light of pragmatic dimension divided the artist emotion and meaning system delivered by Emotive Image, the Phatic Image that arouse inner signification and the Poetic Image which contain artistic and aesthetic meaning within it.

An Efficient Image Matching Scheme Based on Min-Max Similarity for Distorted Images (왜곡 영상을 위한 효과적인 최소-최대 유사도(Min-Max Similarity) 기반의 영상 정합 알고리즘)

  • Heo, Young-Jin;Jeong, Da-Mi;Kim, Byung-Gyu
    • Journal of Korea Multimedia Society
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    • v.22 no.12
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    • pp.1404-1414
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    • 2019
  • Educational books commonly use some copyrighted images with various kinds of deformation for helping students understanding. When using several copyrighted images made by merging or editing distortion in legal, we need to pay a charge to original copyright holders for each image. In this paper, we propose an efficient matching algorithm by separating each copyrighted image with the merged and edited type including rotation, illumination change, and change of size. We use the Oriented FAST and Rotated BRIEF (ORB) method as a basic feature matching scheme. To improve the matching accuracy, we design a new MIN-MAX similarity in matching stage. With the distorted dataset, the proposed method shows up-to 97% of precision in experiments. Also, we demonstrate that the proposed similarity measure also outperforms compared to other measure which is commonly used.

Evaluation of Deep Learning Model for Scoliosis Pre-Screening Using Preprocessed Chest X-ray Images

  • Min Gu Jang;Jin Woong Yi;Hyun Ju Lee;Ki Sik Tae
    • Journal of Biomedical Engineering Research
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    • v.44 no.4
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    • pp.293-301
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    • 2023
  • Scoliosis is a three-dimensional deformation of the spine that is a deformity induced by physical or disease-related causes as the spine is rotated abnormally. Early detection has a significant influence on the possibility of nonsurgical treatment. To train a deep learning model with preprocessed images and to evaluate the results with and without data augmentation to enable the diagnosis of scoliosis based only on a chest X-ray image. The preprocessed images in which only the spine, rib contours, and some hard tissues were left from the original chest image, were used for learning along with the original images, and three CNN(Convolutional Neural Networks) models (VGG16, ResNet152, and EfficientNet) were selected to proceed with training. The results obtained by training with the preprocessed images showed a superior accuracy to those obtained by training with the original image. When the scoliosis image was added through data augmentation, the accuracy was further improved, ultimately achieving a classification accuracy of 93.56% with the ResNet152 model using test data. Through supplementation with future research, the method proposed herein is expected to allow the early diagnosis of scoliosis as well as cost reduction by reducing the burden of additional radiographic imaging for disease detection.

Development of Digital Leaf Authoring Tool for Virtual Landscape Production (가상 조경 생성을위한 디지털 잎 저작도구 개발)

  • Kim, Jinmo
    • Journal of the Korea Computer Graphics Society
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    • v.21 no.5
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    • pp.1-10
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    • 2015
  • This study proposes a method of developing authoring tool that can easily and intuitively generate diverse digital leaves that compose virtual landscape. The main system of the proposed authoring tool consists of deformation method for the contour of leaf blade based on image warping, procedural modeling of leaf vein and visualization method based on mathematical model that expresses the color and brightness of leaves. First, the proposed authoring tool receives leaf input image and searches for contour information on the leaf blades. It then designs leaf blade deformation method that can generate diverse shapes of leaf blades in an intuitive structure using feature-based image warping. Based on the computed leaf blade contour, the system implements the generalized procedural modeling method suitable for the authoring tool that generates natural vein patterns appropriate for the leaf blade shape. Finally, the system applies visualization function that can express color and brightness of leaves and their changes over time using a mathematical model based on convolution sums of divisor functions. This paper provides texture support function so that the digital leaves that were generated using the proposed authoring tool can be used in a variety of three-dimensional digital contents field.

Online Virtual Try On using Mannequin Cloth Pictures (마네킨 의상사진 기반 온라인 가상의상착용)

  • Ahn, Heejune
    • Journal of Korea Society of Industrial Information Systems
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    • v.23 no.6
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    • pp.29-38
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    • 2018
  • In this paper, we developed a virtual cloth try-on (VTON) technology that segement the cloth image worn on the mannequin and applies it to the user 's photograph. The two-dimensional image-based virtual wear study which does not require three-dimensional information of cloth and model is of practical value, but the research result shows that there are limitations of of the current technology for the problem of occlusion or distortion. In this study, we proposed an algorithm to apply the results obtained from the DNN- based segmentation and posture estimation to the user 's photograph, assuming that the mannequin cloth reduces the difficulties in this part. In order to improve the performance compared with the existing one, we used the validity check of the pre-attitude information, the improvement of the deformation using the outline, and the improvement of the divided area. As a result, a significantly improved result image of more than 50% was obtained.