• Title/Summary/Keyword: geometric shape information

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An Effective Data Exchange of Curves (곡선의 효율적 자료 교환)

  • 김혁진
    • Journal of the Korea Society of Computer and Information
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    • v.3 no.3
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    • pp.31-40
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    • 1998
  • Recently computer graphics and CAD systems of many kinds have been developed. and this trends will be more increased in the future because the application fields are diverse However, data exchange problems between these systems will be occurred as the system kinds increase. Standards for solving these problems are made by IGES and STEP. etc, Nevertheless, it is unsatisfactory now because data exchange between different systems is not running well with reliability and efficiency. Because vendors implement with different ways, data exchange of the curves and surfaces between different systems which are based in the geometric modeling system, does not satisfy. This paper is a research for curve conversion in the data exchange between different systems. Also this paper analyzed the transferring data which are effectively conversed the curves among the four different types of curves in the less important curve shape environment.

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A Data Embedding Technique for Image Watermarking using Fresnel Transform (이미지 워터마킹을 위한 Fresnel 변환을 이용한 데이타 삽입 기법)

  • Seok Kang;Yoshinao Aoki
    • Journal of KIISE:Computing Practices and Letters
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    • v.9 no.1
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    • pp.70-76
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    • 2003
  • Digital watermarking is a technique embedding hidden information into multimedia data imperceptibly such as images and sounds. Generally an original image is transformed and coded watermark data is embedded in frequency domain watermarking models. In this paper, We propose a new data embedding method using Fresnel transform. A watermark image is fresnel-transformed and the intensity of transformed pattern is embedded into original image. Our watermarking model has the flexibility In data embedding. It is possible to get many embedding patterns from a single watermark image by using various distance parameters with Fresnel transform. All kinds of image models such af shape, letter and photo ran be used as a watermark data. The watermarking experiments were conducted to show the validity of the proposed method, and the results show that our method has the robustness against lossy compression, filtering and geometric transformation.

A partially occluded object recognition technique using a probabilistic analysis in the feature space (특징 공간상에서 의 확률적 해석에 기반한 부분 인식 기법에 관한 연구)

  • 박보건;이경무;이상욱;이진학
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.11A
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    • pp.1946-1956
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    • 2001
  • In this paper, we propose a novel 2-D partial matching algorithm based on model-based stochastic analysis of feature correspondences in a relation vector space, which is quite robust to shape variations as well as invariant to geometric transformations. We represent an object using the ARG (Attributed Relational Graph) model with features of a set of relation vectors. In addition, we statistically model the partial occlusion or noise as the distortion of the relation vector distribution in the relation vector space. Our partial matching algorithm consists of two-phases. First, a finite number of candidate sets areselected by using logical constraint embedding local and structural consistency Second, the feature loss detection is done iteratively by error detection and voting scheme thorough the error analysis of relation vector space. Experimental results on real images demonstrate that the proposed algorithm is quite robust to noise and localize target objects correctly even inseverely noisy and occluded scenes.

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Object Picking and Concurrency for Solid Modeler in Collaborative Design System (협동설계시스템의 솔리드 모델러를 위한 오브젝트의 Picking과 Concurrency)

  • 윤보열;김응곤
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.4
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    • pp.723-729
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    • 2001
  • We are able to work on the shared virtual space in Web-based Collaborative Design System using only Internet and Web browser. The users connect to the Solid Modeler Server through m and they create 3D shape and manipulate them variously. Then the users will share 3D objects and two problems can arise. The users must be able to pick the objects effectively which they want to manipulate. When one of the users manipulates a particular object, others should not disturb with the same object. In this paper, picking is implemented not only by computing intersection of mouse pointer with the objects of the virtual world, but also by using capabilities and attributes of scene graph node, by setting bounds intersection testing instead of geometric intersection testing, by limiting the scope of the pick testing, using Java 3D. These methods can reduce the computation of picking and can pick 3D objects effectively and easily using the system of hierarchy. To have effective concurrency, we used shared lock and exclusive lock as the action in work space.

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Training Performance Analysis of Semantic Segmentation Deep Learning Model by Progressive Combining Multi-modal Spatial Information Datasets (다중 공간정보 데이터의 점진적 조합에 의한 의미적 분류 딥러닝 모델 학습 성능 분석)

  • Lee, Dae-Geon;Shin, Young-Ha;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.40 no.2
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    • pp.91-108
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    • 2022
  • In most cases, optical images have been used as training data of DL (Deep Learning) models for object detection, recognition, identification, classification, semantic segmentation, and instance segmentation. However, properties of 3D objects in the real-world could not be fully explored with 2D images. One of the major sources of the 3D geospatial information is DSM (Digital Surface Model). In this matter, characteristic information derived from DSM would be effective to analyze 3D terrain features. Especially, man-made objects such as buildings having geometrically unique shape could be described by geometric elements that are obtained from 3D geospatial data. The background and motivation of this paper were drawn from concept of the intrinsic image that is involved in high-level visual information processing. This paper aims to extract buildings after classifying terrain features by training DL model with DSM-derived information including slope, aspect, and SRI (Shaded Relief Image). The experiments were carried out using DSM and label dataset provided by ISPRS (International Society for Photogrammetry and Remote Sensing) for CNN-based SegNet model. In particular, experiments focus on combining multi-source information to improve training performance and synergistic effect of the DL model. The results demonstrate that buildings were effectively classified and extracted by the proposed approach.

Isogeometric Analysis of Mindlin Plate Structures Using Commercial CAD Codes (상용 CAD와 연계한 후판 구조의 아이소-지오메트릭 해석)

  • Lee, Seung-Wook;Koo, Bon-Yong;Yoon, Min-Ho;Lee, Jae-Ok;Cho, Seon-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.24 no.3
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    • pp.329-335
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    • 2011
  • The finite element method (FEM) has been used for various fields like mathematics and engineering. However, the FEM has a difficulty in describing the geometric shape exactly due to its property of piecewise linear discretization. Recently, however, a so-called isogeometric analysis method that uses the non-uniform rational B-spline(NURBS) basis function has been developed. The NURBS can be used to describe the geometry exactly and play a role of basis functions for the response analysis. Nevertheless, constructing the NURBS basis functions in analysis is as costly as a meshing process in the FEM. Since the isogeometric method shares geometric data with CAD, it is possible to intactly import the model data from commercial CAD tools. In this paper, we use the Rhinoceros 3D software to create CAD models and export in the form of STEP file. The information of knot vectors and control points in the NURBS is utilized in the isogeometric analysis. Through some numerical examples, the accuracy of isogeometric method is compared with that of FEM. Also, the efficiency of the isogeometric method that includes the CAD and CAE in a unified framework is verified.

Automatic Extraction of Roof Components from LiDAR Data Based on Octree Segmentation (LiDAR 데이터를 이용한 옥트리 분할 기반의 지붕요소 자동추출)

  • Song, Nak-Hyeon;Cho, Hong-Beom;Cho, Woo-Sug;Shin, Sung-Woong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.25 no.4
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    • pp.327-336
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    • 2007
  • The 3D building modeling is one of crucial components in building 3D geospatial information. The existing methods for 3D building modeling depend mainly on manual photogrammetric processes by stereoplotter compiler, which indeed take great amount of time and efforts. In addition, some automatic methods that were proposed in research papers and experimental trials have limitations of describing the details of buildings with lack of geometric accuracy. It is essential in automatic fashion that the boundary and shape of buildings should be drawn effortlessly by a sophisticated algorithm. In recent years, airborne LiDAR data representing earth surface in 3D has been utilized in many different fields. However, it is still in technical difficulties for clean and correct boundary extraction without human intervention. The usage of airborne LiDAR data will be much feasible to reconstruct the roof tops of buildings whose boundary lines could be taken out from existing digital maps. The paper proposed a method to reconstruct the roof tops of buildings using airborne LiDAR data with building boundary lines from digital map. The primary process is to perform octree-based segmentation to airborne LiDAR data recursively in 3D space till there are no more airborne LiDAR points to be segmented. Once the octree-based segmentation has been completed, each segmented patch is thereafter merged based on geometric spatial characteristics. The experimental results showed that the proposed method were capable of extracting various building roof components such as plane, gable, polyhedric and curved surface.

Development of Chicken Carcass Segmentation Algorithm using Image Processing System (영상처리 시스템을 이용한 닭 도체 부위 분할 알고리즘 개발)

  • Cho, Sung-Ho;Lee, Hyo-Jai;Hwang, Jung-Ho;Choi, Sun;Lee, Hoyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.3
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    • pp.446-452
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    • 2021
  • As a higher standard for food consumption is required, the consumption of chicken meat that can satisfy the subdivided food preferences is increasing. In March 2003, the quality criteria for chicken carcasses notified by the Livestock Quality Assessment Service suggested quality grades according to fecal contamination and the size and weight of blood and bruises. On the other hand, it is too difficult for human inspection to qualify mass products, which is key to maintaining consistency for grading thousands of chicken carcasses. This paper proposed the computer vision algorithm as a non-destructive inspection, which can identify chicken carcass parts according to the detailed standards. To inspect the chicken carcasses conveyed at high speed, the image calibration was involved in providing robustness to the side effect of external lighting interference. The separation between chicken and background was achieved by a series of image processing, such as binarization based on Expectation Maximization, Erosion, and Labeling. In terms of shape analysis of chicken carcasses, the features are presented to reveal geometric information. After applying the algorithm to 78 chicken carcass samples, the algorithm was effective in segmenting chicken carcass against a background and analyzing its geometric features.

A Study on the Image of Adult Foundations (남.녀 파운데이션 이미지 연구)

  • Lee, Hyo-Jin;Yang, A-Rang
    • The Research Journal of the Costume Culture
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    • v.19 no.2
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    • pp.255-268
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    • 2011
  • This study carefully explored today's preferable beauty images, analyzed Korean adult purchasing trends of functional underwear and market analysis of the most popular items and their designs. Information and methods are based largely on reference book material as well as analysis of real domestic data. The paper's research timeline simply spans the last three years, as in accordance with project parameters. Helping improve body shape, foundation literally means 'substructur' and 'base'. The formativeness in these adult foundations typically has three main category classifications. First, natural modern image. This is where we find natural beauty including that which embodies a cool modern sense. Here, you can often see such patterns as either stripes and dots, or simply no patterns at all. Colors are green, red-brown, incarnadine, or khaki from a natural or basic human body color. Its products are marketed as both solid and durable eco-friendly materials, and lace-seethrough. Fashion's natural modern image is undoubtedly the most popular style purchase choice among both genders. Second, sweet romantic image. This mainly consists of two concepts : a sweet and romantic theme, and visual appeal. Patterns include flowers, lips, heart, stars, candies and various other appealing characters. Its main colors are pink, yellow, red, purple, and violet. Products are decorated with laces, frills and ribbons. Since only men's semi-girdles carry such designs, this fashion foundation is largely a women's world. While men show an obvious interest in foundation, they still mostly prefer the choice of natural modern images. Third, mystic sexy image. This is defined as all feminine images of mysterious and classic sexual beauty. Patterns are variously expressed as paisley, flowers, and geometric. Colors are largely purple, blue-green, royal-blue, cobalt, and black. Products are commonly decorated with beading, spangles, hot-fixes and so on. While this image can be found in all kinds of women's foundations, it typically appears only in men's corsets and girdles.

Structural Simplicity Examined from a Perspective of the Comparison of Architecture and Fashion (건축과 패션의 비교를 통해 고찰한 구조적 단순성)

  • Park, Seon-Ji
    • Journal of the Korea Fashion and Costume Design Association
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    • v.17 no.1
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    • pp.1-11
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    • 2015
  • Fashion and architecture essentially have structure to build space for a form of three dimensions. This study defines the form in which structure in itself becomes design as structural simplicity and investigates design paying attention to only structure. It is one of efforts in order to display new design required in the age of a flood of design and it is considered that before developing design through the fusion of architecture and fashion, understanding structure which is the most fundamental element to constitute the form of the two genres will be a groundwork to develop proper fusion design. This study elucidates similarities between architecture and fashion through literature review and investigates structure meant in architecture and fashion, and after that, collects corresponding examples through related literature and fashion information site. For structural simplicity in architecture, structure of a building in itself is a form and decoration at the same time, and it appears as a form of minimizing other elements and stressing the structure only. Structure in fashion means composition line which essentially exists to embody two dimensional materials onto three dimensional human body. As elements of geometric lines are creatively expressed by a designer in order to constitute three dimensional form from structural simplicity, they connote a variety of functions and exert decorative effects as well. And the shape of structure expressed like this is employed as a tool to show off the designer's techniques.

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