• Title/Summary/Keyword: Classification:

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Comparison of Variable Importance Measures in Tree-based Classification (나무구조의 분류분석에서 변수 중요도에 대한 고찰)

  • Kim, Na-Young;Lee, Eun-Kyung
    • The Korean Journal of Applied Statistics
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    • v.27 no.5
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    • pp.717-729
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    • 2014
  • Projection pursuit classification tree uses a 1-dimensional projection with the view of the most separating classes in each node. These projection coefficients contain information distinguishing two groups of classes from each other and can be used to calculate the importance measure of classification in each variable. This paper reviews the variable importance measure with increasing interest in line with growing data size. We compared the performances of projection pursuit classification tree with those of classification and regression tree(CART) and random forest. Projection pursuit classification tree are found to produce better performance in most cases, particularly with highly correlated variables. The importance measure of projection pursuit classification tree performs slightly better than the importance measure of random forest.

Relationship Between Function Classification Systems and the PEDI Functional Skills in Children With Cerebral Palsy (뇌성마비 아동에서 기능분류체계와 소아장애평가척도의 기능적 기술 사이 관련성)

  • Park, Eun-Young;Kim, Won-Ho
    • Physical Therapy Korea
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    • v.21 no.3
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    • pp.55-62
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    • 2014
  • This study investigated the relationship between function classification systems and the Pediatric Evaluation of Disability Inventory (PEDI) functional skills in children with cerebral palsy (CP). Two hundred and eleven children with CP participated in this study. The Korean-Gross Motor Function Classification System (K-GMFCS), Korean-Manual Ability Classification System (K-MACS), Korean-Communication Function Classification System (K-CFCS), and self-care, mobility, and social function domains of the Korean-Pediatric Evaluation of Disability Inventory (K-PEDI) functional skills were measured by physical therapists or occupational therapists. All of the function classification systems were significantly correlated with PEDI functional skills ($r_s$=-.549 to -.826) (p<.05). Especially, K-GMFCS, K-MACS, and K-CFCS were correlated significantly with mobility, self-care, and social function, respectively. Using stepwise multiple regression analysis, we established that K-GMFCS, K-MACS, and K-CFCS were predictors of self-care skills (74.3%) and mobility skills (79.5%) of the K-PEDI (p<.05). In addition, K-CFCS and K-MACS were predictors of social function (65.9%) of the K-PEDI (p<.05). The information gathered in this study using the levels measured in the function classification systems may be useful to clinicians for estimating the PEDI functional skills in children with CP.

Effective Fingerprint Classification using Subsumed One-Vs-All Support Vector Machines and Naive Bayes Classifiers (포섭구조 일대다 지지벡터기계와 Naive Bayes 분류기를 이용한 효과적인 지문분류)

  • Hong, Jin-Hyuk;Min, Jun-Ki;Cho, Ung-Keun;Cho, Sung-Bae
    • Journal of KIISE:Software and Applications
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    • v.33 no.10
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    • pp.886-895
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    • 2006
  • Fingerprint classification reduces the number of matches required in automated fingerprint identification systems by categorizing fingerprints into a predefined class. Support vector machines (SVMs), widely used in pattern classification, have produced a high accuracy rate when performing fingerprint classification. In order to effectively apply SVMs to multi-class fingerprint classification systems, we propose a novel method in which SVMs are generated with the one-vs-all (OVA) scheme and dynamically ordered with $na{\ddot{i}}ve$ Bayes classifiers. More specifically, it uses representative fingerprint features such as the FingerCode, singularities and pseudo ridges to train the OVA SVMs and $na{\ddot{i}}ve$ Bayes classifiers. The proposed method has been validated on the NIST-4 database and produced a classification accuracy of 90.8% for 5-class classification. Especially, it has effectively managed tie problems usually occurred in applying OVA SVMs to multi-class classification.

Potential of Bidirectional Long Short-Term Memory Networks for Crop Classification with Multitemporal Remote Sensing Images

  • Kwak, Geun-Ho;Park, Chan-Won;Ahn, Ho-Yong;Na, Sang-Il;Lee, Kyung-Do;Park, No-Wook
    • Korean Journal of Remote Sensing
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    • v.36 no.4
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    • pp.515-525
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    • 2020
  • This study investigates the potential of bidirectional long short-term memory (Bi-LSTM) for efficient modeling of temporal information in crop classification using multitemporal remote sensing images. Unlike unidirectional LSTM models that consider only either forward or backward states, Bi-LSTM could account for temporal dependency of time-series images in both forward and backward directions. This property of Bi-LSTM can be effectively applied to crop classification when it is difficult to obtain full time-series images covering the entire growth cycle of crops. The classification performance of the Bi-LSTM is compared with that of two unidirectional LSTM architectures (forward and backward) with respect to different input image combinations via a case study of crop classification in Anbadegi, Korea. When full time-series images were used as inputs for classification, the Bi-LSTM outperformed the other unidirectional LSTM architectures; however, the difference in classification accuracy from unidirectional LSTM was not substantial. On the contrary, when using multitemporal images that did not include useful information for the discrimination of crops, the Bi-LSTM could compensate for the information deficiency by including temporal information from both forward and backward states, thereby achieving the best classification accuracy, compared with the unidirectional LSTM. These case study results indicate the efficiency of the Bi-LSTM for crop classification, particularly when limited input images are available.

A Study on the Model for Construction Records Classification System (건설기록물 분류체계 모형에 관한 연구)

  • Park, Yong-Boo;Kim, Tae-Soo
    • Journal of the Korean Society for information Management
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    • v.28 no.3
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    • pp.83-101
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    • 2011
  • The international standards, ISO 15489 and Family Code, recommend using functional classification method both in public and private organizations. In this study made a comparative analysis of the details of classification systems through case studies on records classification systems of a total of seven comprehensive construction companies in Korea including three large corporations and four small and medium-size businesses. Findings of this study suggester the direction of developing construction records classification system and its methodology. By summarizing classification standards derived from these case studies, key construction records classification standards were presented.

An Application of Spatial Classification Methods for the Improvement of Classification Accuracy (분류정확도 향상을 위한 공간적 분류방법의 적용)

  • Jeong, Jae-Joon;Lee, Byoung-Kil;Kim, Hyung-Tae;Kim, Yong-Il
    • Journal of Korean Society for Geospatial Information Science
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    • v.9 no.2 s.18
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    • pp.37-46
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    • 2001
  • Spectral pattern recognition techniques are most used in classification of remotely sensed data. Yet, in any real image, adjacent pixels are related, because imaging sensors acquire significant portions of energy from adjacent pixels. And, with the continued improvement in the spatial resolution of remote sensing systems, another spatial pattern recognition approach is must considered. In this study, we aim to show the potentiality of spatial classification methods through comparing the accuracies of spectral classification methods and those of spectral classification methods. By the comparisons between the two methods, classification accuracies of 6 different spatial classification methods are higher than that of spectral classification method by 2-6% or so. Additionally, we can show it statistically through the classification experiments with different band combinations.

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An Empirical Study on the Land Cover Classification Method using IKONOS Image (IKONOS 영상의 토지피복분류 방법에 관한 실증 연구)

  • Sakong, Hosang;Im, Jungho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.6 no.3
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    • pp.107-116
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    • 2003
  • This study investigated how appropriate the classification methods based on conventional spectral characteristics are for high resolution imagery. A supervised classification mixing parametric and non-parametric rules, a method in which fuzzy theory is applied to such classification, and an unsupervised method were performed and compared to each other for accuracy. In addition, comparing the result screen-digitized through interpretation to the classification result using spectral characteristics, this study analyzed the conformity of both methods. Although the supervised classification to which fuzzy theory was applied showed the best performance, the application of conventional classification techniques to high resolution imagery had some limitations due to there being too much information unnecessary to classification, shadows, and a lack of spectral information. Consequently, more advanced techniques including integration with other advanced remote sensing technologies, such as lidar, and application of filtering or template techniques, are required to classify land cover/use or to extract useful information from high resolution imagery.

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Classification System Model Design for Algorithm Education for Elementary and Secondary Students (초중등학생 대상 알고리즘 교육을 위한 분류체계 모형 설계)

  • Lee, Young-ho;Koo, Duk-hoi
    • Journal of The Korean Association of Information Education
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    • v.21 no.3
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    • pp.297-307
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    • 2017
  • The purpose of this study is to propose algorithm classification system for algorithm education for Elementary and Secondary Students. We defines the components of the algorithm and expresses the algorithm classification system by the analysis synthesis method. The contents of the study are as follows. First, we conducted a theoretical search on the classification purpose and classification. Second, the contents and limitations of the classification system for the proposed algorithm contents were examined. In addition, we examined the contents and selection criteria of algorithms used in algorithm education research. Third, the algorithm components were redefined using the core idea and crosscutting concept proposed by the NRC. And the crosscutting concept of algorithm is subdivided into algorithm data structure and algorithm design strategy, and its contents are presented using analytic synthesis classification scheme. Finally, the validity of the proposed contents was verified by the review of the expert group. It is expected that the study on the algorithm classification system will provide many implications for the contents selection and training method in the algorithm education.

A Rule-Based Image Classification Method for Analysis of Urban Development in the Capital Area (수도권 도시개발 분석을 위한 규칙기반 영상분류)

  • Lee, Jin-A;Lee, Sung-Soon
    • Spatial Information Research
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    • v.19 no.6
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    • pp.43-54
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    • 2011
  • This study proposes a rule-based image classification method for the time-series analysis of changes in the land surface of the Seongnam-Yongin area using satellite-image data from 2000 to 2009. In order to identify the change patterns during each period, 11 classes were employed in accordance with statistical/mathematic rules. A generalized algorithm was used so that the rules could be applied to the unsupervised-classification method that does not establish any training sites. The results showed that the urban area of the object increased by 145% due to housing-site development. The image data from 2009 had a classification accuracy of 98%. For method verification, the results were compared to land-cover changes through Post-classification comparison. The maximum utilization of the available data within multiple images and the optimized classification allowed for an improvement in the classification accuracy. The proposed rule-based image-classification method is expected to be widely employed for the time-series analysis of images to produce a thematic map for urban development and to monitor urban development and environmental change.

An Evaluation of the Use of the Texture in Land Cover Classification Accuracy from SPOT HRV Image of Pusan Metropolitan Area (SPOT HRV 영상을 이용한 부산 지역 토지피복분류에 있어서의 질감의 기여에 관한 평가)

  • Jung, In-Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.2 no.1
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    • pp.32-44
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    • 1999
  • Texture features can be incorporated in classification procedure to resolve class confusions. However, there have been few application-oriented studies made to evaluate the relative powers of texture analysis methods in a particular environment. This study evaluates the increases in the land-cover classification accuracy of the SPOT HRV multispectral data of Pusan Metropolitan area from texture processing. Twenty-four texture measures were derived from the SPOT HRV band 3 image. Each of these features were used in combination with the three spectral images in the classification of 10 land-cover classes. Supervised training and a Gaussian maximum likelihood classifier were used in the classification. It was found that while entropy produces the best empirical results in terms of the overall classification, other texture features can also largely improve the classification accuracies obtained by the use of the spectral images only. With the inclusion of texture, the classification for each category improves. Specially, urban built-up areas had much increase in accuracy. The results indicate that texture size 5 by 5 and 7 by 7 may be suitable at land cover classification of Pusan Metropolitan area.

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