• Title/Summary/Keyword: Shape Classification

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New Approaches to Ultrasonic Classification and Sizing of Flaws in Weldments (초음파시험에 의한 용접결함의 종류판별과 크기산정의 새로운 기법)

  • 송성진
    • Journal of Welding and Joining
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    • v.13 no.4
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    • pp.132-146
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    • 1995
  • Flaw classification(determination of the flaw type) and flaw sizing (prediction of the flaw shape, orientation and sizing parameters) are very important issues in ultrasonic nondestructive evaluation of weldments. In this work, new techniques for both classification and sizing of flaws in weldments are described together with extensive review of previous works on both topics. In the area of flaw classification, a methodology is developed which can solve classification problems using probabilistic neural networks, and in the area of flaw sizing, a time-of-flight equivalent(TOFE) sizing method is presented.

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Naive Bayes classifiers boosted by sufficient dimension reduction: applications to top-k classification

  • Yang, Su Hyeong;Shin, Seung Jun;Sung, Wooseok;Lee, Choon Won
    • Communications for Statistical Applications and Methods
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    • v.29 no.5
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    • pp.603-614
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    • 2022
  • The naive Bayes classifier is one of the most straightforward classification tools and directly estimates the class probability. However, because it relies on the independent assumption of the predictor, which is rarely satisfied in real-world problems, its application is limited in practice. In this article, we propose employing sufficient dimension reduction (SDR) to substantially improve the performance of the naive Bayes classifier, which is often deteriorated when the number of predictors is not restrictively small. This is not surprising as SDR reduces the predictor dimension without sacrificing classification information, and predictors in the reduced space are constructed to be uncorrelated. Therefore, SDR leads the naive Bayes to no longer be naive. We applied the proposed naive Bayes classifier after SDR to build a recommendation system for the eyewear-frames based on customers' face shape, demonstrating its utility in the top-k classification problem.

The Effect of Reference Mic. Array Shape on MUSIC and Beamforming Methods in Acoustical Holography (음향 홀로그래피에서 기준 마이크로폰 어레이가 빔형성 방법과 다중 신호 분리 방법에 미치는 영향)

  • 이원혁;이명준;강연준
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.1003-1008
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    • 2001
  • In beamforming method, source positions are predicted by MUSIC (Multiple Signal Classification) power method and composite sound fields can then be decomposed into each partial field by beamforming, detenninistically without restriction of the distance between reference microphones and sources. However, reference microphone array shape is important in both MUSIC and beamforming method. Thus the present paper describes the effect of the reference microphone array shape.

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A study on the classification of body types for female junior high school students - Focused on the development of school uniforms - (여자 중학생의 체형분류에 관한 연구 - 교복패턴개발을 중심으로 -)

  • Shin, Jang-Hee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.22 no.3
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    • pp.99-110
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    • 2020
  • In terms of junior high school girls' growth patterns during early adolescence, are unlike childhood when relatively balanced growth patterns are found and high school years in which the normal adult body type is nearly reached, growth patterns displayed are imbalanced and rapid. In fact, diverse size changes by body part growth occur significantly different from individual to individual. Therefore, it has been hard for junior high school students to select their proper size when buying school uniforms. This study attempted to acquire basic data needed to address adolescent body shapes and school uniform patterns for junior high school girls, using the data from the 7th Size Korea Survey (2015). Specifically, it provides basic data for the development of school uniform patterns through the classification of their body into particular types, After extracting body shape components and a cluster analysis using ANOVA. According to a factor analysis conducted to determine body shape components, six factors were obtained: Factor 1: bulk and horizontal size, Factor 2: body height and length, Factor 3: shoulder shape and length, Factor 4: shape of upper body, Factor 5: lower drop, Factor 6: upper drop with a variance of 81.46%. To classify junior high school girls' body shape and determine their characteristics, a cluster analysis was performed with the variables obtained using factor analysis. Body shape was classified into three different types: Type 1 accounted for 30.7%. This was a short, slender body with the smallest bulk, size, and upper drop. Type 2 accounted for 24.9%. This was the largest in bulk and horizontal size and highest and length as well. Type 3 accounted for 44.5%. This type was close to average in terms of horizontal size, length and height, and high drop values. To develop school uniforms with great accuracy and body fit for junior high school students, there should be further studies on changes in body shape and their causes. The study results can serve as basic data for comparing branded school uniform patterns for junior high school girls and developing school uniform patterns based on body shape, using 3D virtual clothing simulations.

Performance Evaluations for Leaf Classification Using Combined Features of Shape and Texture (형태와 텍스쳐 특징을 조합한 나뭇잎 분류 시스템의 성능 평가)

  • Kim, Seon-Jong;Kim, Dong-Pil
    • Journal of Intelligence and Information Systems
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    • v.18 no.3
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    • pp.1-12
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    • 2012
  • There are many trees in a roadside, parks or facilities for landscape. Although we are easily seeing a tree in around, it would be difficult to classify it and to get some information about it, such as its name, species and surroundings of the tree. To find them, you have to find the illustrated books for plants or search for them on internet. The important components of a tree are leaf, flower, bark, and so on. Generally we can classify the tree by its leaves. A leaf has the inherited features of the shape, vein, and so on. The shape is important role to decide what the tree is. And texture included in vein is also efficient feature to classify them. This paper evaluates the performance of a leaf classification system using both shape and texture features. We use Fourier descriptors for shape features, and both gray-level co-occurrence matrices and wavelets for texture features, and used combinations of such features for evaluation of images from the Flavia dataset. We compared the recognition rates and the precision-recall performances of these features. Various experiments showed that a combination of shape and texture gave better results for performance. The best came from the case of a combination of features of shape and texture with a flipped contour for a Fourier descriptor.

A Study on Women′s Face Types Classification by Visual Distinction and Difference from the Measurement (시각적 판단에 의한 얼굴유형 분류와 계측 특성 연구)

  • Namwon Moon
    • The Research Journal of the Costume Culture
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    • v.8 no.1
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    • pp.133-144
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    • 2000
  • The purpose of this study was to classify women's face types by visual distinction and to analyze the measurement of face types. A survey was conducted by subjects of 167 women's college students in Kwangju City and Chonnam area. Data were analyzed by Frequencies, Mean, one way ANOVA and Ducan's Multiple Range Test. The major results were as followed ; ·Women's face types were classified by 7 types and there were oblong shape(28.3%), egg shape(25.7%), round shape(23.9%), square shape(12.4%), inverted triangle shape(5.3%), diamond shape(3.5%), triangle shape(0.8%) in the subjects. ·From the measurements of the women's face, index of face length to face breadth was 1.38, it means that the index was different from the other refferences. And the lower face length was longer than the upper and the middle face lengths. ·Differences From those measurements like forehead breadth, face length/bizigion breath(p〈.001), bizigion breadth, bignathion slopper, stature(p〈.01) and trichion breadth, tragion-menton length(p〈.05) were significant in the classified face types.

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Automated Classification of Ground-glass Nodules using GGN-Net based on Intensity, Texture, and Shape-Enhanced Images in Chest CT Images (흉부 CT 영상에서 결절의 밝기값, 재질 및 형상 증강 영상 기반의 GGN-Net을 이용한 간유리음영 결절 자동 분류)

  • Byun, So Hyun;Jung, Julip;Hong, Helen;Song, Yong Sub;Kim, Hyungjin;Park, Chang Min
    • Journal of the Korea Computer Graphics Society
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    • v.24 no.5
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    • pp.31-39
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    • 2018
  • In this paper, we propose an automated method for the ground-glass nodule(GGN) classification using GGN-Net based on intensity, texture, and shape-enhanced images in chest CT images. First, we propose the utilization of image that enhances the intensity, texture, and shape information so that the input image includes the presence and size information of the solid component in GGN. Second, we propose GGN-Net which integrates and trains feature maps obtained from various input images through multiple convolution modules on the internal network. To evaluate the classification accuracy of the proposed method, we used 90 pure GGNs, 38 part-solid GGNs less than 5mm with solid component, and 23 part-solid GGNs larger than 5mm with solid component. To evaluate the effect of input image, various input image set is composed and classification results were compared. The results showed that the proposed method using the composition of intensity, texture and shape-enhanced images showed the best result with 82.75% accuracy.

A Study on Classification of Micro-Cracks in Silicon Wafer Through the Fusion of Principal Component Analysis and Neural Network (주성분분석과 신경회로망의 융합을 통한 실리콘 웨이퍼의 마이크로 크랙 분류에 관한 연구)

  • Seo, Hyoung Jun;Kim, Gyung Bum
    • Journal of the Korean Society for Precision Engineering
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    • v.32 no.5
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    • pp.463-470
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    • 2015
  • Solar cell is typical representative of renewable green energy. Silicon wafer contributes about 66 percent to its cost structure. In its manufacturing, micro-cracks are often occurred due to manufacturing process such as wire sawing, grinding and cleaning. Their detection and classification are important to process feedback information. In this paper, a classification method of micro-cracks is proposed, based on the fusion of principal component analysis(PCA) and neural network. The proposed method shows that it gives higher results than single application of two methods, in terms of shape and size classification of micro-cracks.

Sasang Constitution Classification System by Morphological Feature Extraction of Facial Images

  • Lee, Hye-Lim;Cho, Jin-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.8
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    • pp.15-21
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    • 2015
  • This study proposed a Sasang constitution classification system that can increase the objectivity and reliability of Sasang constitution diagnosis using the image of frontal face, in order to solve problems in the subjective classification of Sasang constitution based on Sasang constitution specialists' experiences. For classification, characteristics indicating the shapes of the eyes, nose, mouth and chin were defined, and such characteristics were extracted using the morphological statistic analysis of face images. Then, Sasang constitution was classified through a SVM (Support Vector Machine) classifier using the extracted characteristics as its input, and according to the results of experiment, the proposed system showed a correct recognition rate of 93.33%. Different from existing systems that designate characteristic points directly, this system showed a high correct recognition rate and therefore it is expected to be useful as a more objective Sasang constitution classification system.

A Research on Improving the Shape of Korean Road Signs to Enhance LiDAR Detection Performance (LiDAR 시인성 향상을 위한 국내 교통안전표지 형상개선에 대한 연구)

  • Ji yoon Kim;Jisoo Kim;Bum jin Park
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.22 no.3
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    • pp.160-174
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    • 2023
  • LiDAR plays a key role in autonomous vehicles, and to improve its visibility, it is necessary to improve its performance and the detection objects. Accordingly, this study proposes a shape for traffic safety signs that is advantageous for self-driving vehicles to recognize. Improvement plans are also proposed using a shape-recognition algorithm based on point cloud data collected through LiDAR sensors. For the experiment, a DBSCAN-based road-sign recognition and classification algorithm, which is commonly used in point cloud research, was developed, and a 32ch LiDAR was used in an actual road environment to conduct recognition performance tests for 5 types of road signs. As a result of the study, it was possible to detect a smaller number of point clouds with a regular triangle or rectangular shape that has vertical asymmetry than a square or circle. The results showed a high classification accuracy of 83% or more. In addition, when the size of the square mark was enlarged by 1.5 times, it was possible to classify it as a square despite an increase in the measurement distance. These results are expected to be used to improve dedicated roads and traffic safety facilities for sensors in the future autonomous driving era and to develop new facilities.