• Title/Summary/Keyword: local features

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Local Appearance-based Face Recognition Using SVM and PCA (SVM과 PCA를 이용한 국부 외형 기반 얼굴 인식 방법)

  • Park, Seung-Hwan;Kwak, No-Jun
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.3
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    • pp.54-60
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    • 2010
  • The local appearance-based method is one of the face recognition methods that divides face image into small areas and extracts features from each area of face image using statistical analysis. It collects classification results of each area and decides identity of a face image using a voting scheme by integrating classification results of each area of a face image. The conventional local appearance-based method divides face images into small pieces and uses all the pieces in recognition process. In this paper, we propose a local appearance-based method that makes use of only the relatively important facial components. The proposed method detects the facial components such as eyes, nose and mouth that differs much from person to person. In doing so, the proposed method detects exact locations of facial components using support vector machines (SVM). Based on the detected facial components, a number of small images that contain the facial parts are constructed. Then it extracts features from each facial component image using principal components analysis (PCA). We compared the performance of the proposed method to those of the conventional methods. The results show that the proposed method outperforms the conventional local appearance-based method while preserving the advantages of the conventional local appearance-based method.

Cytologic Features of the Chordoma - Report of five cases - (척삭종의 세포학적 소견 -5 예 보고-)

  • Kim, Dong-Hoon;Khang, Shin-Kwang;Gong, Gyung-Yub
    • The Korean Journal of Cytopathology
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    • v.12 no.2
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    • pp.105-110
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    • 2001
  • Chordoma is a rare, clinically and morphologically well characterized tumor, which arises from remnants of the notochord, The majority(60%) occurs in the sacrococcygeal region, with 25% in the clival legion, and 15% in the spine. Although most chordomas do not develop metastasis, the long term prognosis is very poor due to local progressive tumor growth and tendency to recur if incompletely excised. The chordoma has characteristic cytologic features which make a preoperative diagnosis possible. We reviewed the cytologic findings of five patients with chordoma(one oropharynx, two clivus, and two sacrum). The patients were three male and two female, aged from 29 to 77 years(mean 60). Of five chordomas, there were local recurrences in two cases and metastasis of lymph node In one case. Four were FNA smears and one was squash smear taken from intraoperative consultation. All five cases show similar cytologic features. The dominating tumor cells were large with round nuclei and pale-stained vacuolated cytoplasm. The small round uniform cells and short spindle-shaped cells were frequently noted. The cells were surrounded by myxoid or mucoid matrix. The chordoma has characteristic cytologic features which make a preoperative diagnosis possible.

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New Feature Selection Method for Text Categorization

  • Wang, Xingfeng;Kim, Hee-Cheol
    • Journal of information and communication convergence engineering
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    • v.15 no.1
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    • pp.53-61
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    • 2017
  • The preferred feature selection methods for text classification are filter-based. In a common filter-based feature selection scheme, unique scores are assigned to features; then, these features are sorted according to their scores. The last step is to add the top-N features to the feature set. In this paper, we propose an improved global feature selection scheme wherein its last step is modified to obtain a more representative feature set. The proposed method aims to improve the classification performance of global feature selection methods by creating a feature set representing all classes almost equally. For this purpose, a local feature selection method is used in the proposed method to label features according to their discriminative power on classes; these labels are used while producing the feature sets. Experimental results obtained using the well-known 20 Newsgroups and Reuters-21578 datasets with the k-nearest neighbor algorithm and a support vector machine indicate that the proposed method improves the classification performance in terms of a widely known metric ($F_1$).

Image Retrieval Using the Fusion of Texture Features (질감특징들의 융합을 이용한 영상검색)

  • 천영덕;서상용;김남철
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.3A
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    • pp.258-267
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    • 2002
  • We present an image retrieval method for improving retrieval performance by effective fusion of entropy features in wavelet region and wavelet moments. In this method, entropy features are sensitive to the local variation of gray level and well extract valley and edges. These features are effectively applied to contend-based image retrieval by well fusing to wavelet moments that represent texture property in multi-resolution. In order to evaluate the performance of the proposed method. We use Corel Draw Photo DB. Experiment results show that the proposed yields 11% better performance for Corel Draw Photo DB over wavelet moments method.

Generative Process Planning through Feature Recognition (특징형상 인식을 통한 창성적 자동 공정계획 수립 - 복합특징형상 분류를 중심을 -)

  • 이현찬;이재현
    • Korean Journal of Computational Design and Engineering
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    • v.3 no.4
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    • pp.274-282
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    • 1998
  • A feature is a local shape of a product directly related to the manufacturing process. The feature plays a role of the bridge connecting CAD and CAM. In the process planning for he CAM, information on manufacturing is required. To get the a manufacturing information from CAD dat, we need to recognize features. Once features are recognized, they are used as an input for the process planning. In this paper, we thoroughly investigate the composite features, which are generated by interacting simple features. The simple features in the composite feature usually have precedence relation in terms of process sequence. Based on the reason for the precedence relation, we classify the composite features for the process planning. In addition to the precedence relation, approach direction is used as an input for the process planning. In the process planning, the number of set-up orientations are minimized whole process sequence for the features are generated. We propose a process planning algorithm based on the topological sort and breadth-first search of graphs. The algorithn is verified using sample products.

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Terrain Classification Using Three-Dimensional Co-occurrence Features (3차원 Co-occurrence 특징을 이용한 지형분류)

  • Jin Mun-Gwang;Woo Dong-Min;Lee Kyu-Won
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.1
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    • pp.45-50
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    • 2003
  • Texture analysis has been efficiently utilized in the area of terrain classification. In this application features have been obtained in the 2D image domain. This paper suggests 3D co-occurrence texture features by extending the concept of co-occurrence to 3D world. The suggested 3D features are described using co-occurrence histogram of digital elevations at two contiguous position as co-occurrence matrix. The practical construction of co-occurrence matrix limits the number of levels of digital elevation. If the digital elevation is quantized into the number of levels over the whole DEM(Digital Elevation Map), the distinctive features can not be obtained. To resolve the quantization problem, we employ local quantization technique which preserves the variation of elevations. Experiments has been carried out to verify the proposed 3D co-occurrence features, and the addition of the suggested features significantly improves the classification accuracy.

Damage Monitoring of PSC Girder Bridges based on Acceleration -Impedance Signals under Uncertain Temperature Conditions (불확실한 온도 조건하의 PSC 거더 교량의 가속도-임피던스기반 손상 모니터링)

  • Hong, Dong-Soo;Kim, Jeong-Tae
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.24 no.1
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    • pp.107-117
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    • 2011
  • In this study, the effect of temperature-induced uncertainty to damage monitoring using acceleration-impedance response features is analyzed for presterssed concrete(PSC) girder bridges. Firstly, a damage monitoring algorithm using global and local vibration features is designed. As global and local features, acceleration and electro-mechanical impedance features are selected respectively. Secondly, the temperature effect on the acceleration and impedance features for a lab-scaled PSC girder is experimentally analyzed. From the experimental results, compensation models for temperature-acceleration features and temperature-impedance features are estimated. Finally, the feasibility of the acceleration-impedance-based damage monitoring technique using the compensation model is evaluated in the PSC girder for which a set of prestress-loss and flexural stiffness loss cases were dynamically tested.

A Study on the Inner Space Characteristics of Local Government Civil Service Space of Seoul City (서울시 구청 대민서비스공간의 실내공간특성에 관한 연구)

  • Park, Sun-Ju;Kim, Moon-Duck
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2008.05a
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    • pp.258-263
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    • 2008
  • This study aims to investigate the changing roles of Local Government and the ways to improve the space plan, especially focusing on the Local Government civil service space of Seoul City. Recently, many Local Government have endeavored to get rid of the authoritative images and change themselves to a space featuring cultural functions and efficient performance. Local Government buildings in Seoul City are trying to decorate the inner and outer images through new construction or extension of buildings so as to become more friendly to residents. Such efforts are visualized especially in civil service space. Civil service space represents the whole image and role of the Local Government. In addition, civil service space and resting space, which are frequently used, are correlated and more and more accessible to each other as administrative and civil services are increasing. By integrating and developing such features, civil service space of Local Government that meets the requirements of the new era will be presented.

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Color Image Retrieval Using Block-based Classification (블록단위 특성분류를 이용한 컬러영상 검색)

  • 류명분;우석훈;박동권;원치선
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1996.06a
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    • pp.63-66
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    • 1996
  • In this paper, we propose a new content-based color image retrieval algorithm. The algorithm makes use of two features; colors as global features and block classification results as local features. More specifically, we obtain R, G, B color histograms and classify nonoverlapping small image blocks into texture, monotone, and various edges, then using these histograms and classification results were make a similarity measure. Experimental results show that retrieval rate of the proposed algorithm is higher than the previous method.

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Feature-based Object Tracking using an Active Camera (능동카메라를 이용한 특징기반의 물체추적)

  • 정영기;호요성
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.3
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    • pp.694-701
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    • 2004
  • In this paper, we proposed a feature-based tracking system that traces moving objects with a pan-tilt camera after separating the global motion of an active camera and the local motion of moving objects. The tracking system traces only the local motion of the comer features in the foreground objects by finding the block motions between two consecutive frames using a block-based motion estimation and eliminating the global motion from the block motions. For the robust estimation of the camera motion using only the background motion, we suggest a dominant motion extraction to classify the background motions from the block motions. We also propose an efficient clustering algorithm based on the attributes of motion trajectories of corner features to remove the motions of noise objects from the separated local motion. The proposed tracking system has demonstrated good performance for several test video sequences.