• Title/Summary/Keyword: feature

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Feature-based Extraction of Machining Features (특징형상 접근방법에 의한 가공특징형상 추출)

  • 이재열;김광수
    • Korean Journal of Computational Design and Engineering
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    • v.4 no.2
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    • pp.139-152
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    • 1999
  • This paper presents a feature-based approach to extracting machining features fro a feature-based design model. In the approach, a design feature to machining feature conversion process incrementally converts each added design feature into a machining feature or a set of machining features. The proposed approach an efficiently handle protrusion features and interacting features since it takes advantage of design feature information, design intent, and functional requirements during feature extraction. Protrusion features cannot be directly mapped into machining features so that the removal volumes surrounding protrusion features are extracted and converted it no machining features. By utilizing feature information as well as geometry information during feature extraction, the proposed approach can easily overcome inherent problems relating to feature recognition such as feature interactions and loss of design intent. In addition, a feature extraction process can be simplified, and a large set of complex part can be handled with ease.

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A study on the Restoration of Feature Information in STEPAP224 to Solid model (STEP AP224에 표현된 특징형상 정보의 솔리드 모델 복원에 관한 연구)

  • 김야일;강무진
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.367-372
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    • 2001
  • Feature restoration is that restore feature to 3D solid model using the feature information in STEP AP224. Feature is very important in CAPP, but feature information is defined very complicated in STEP AP224. This paper recommends the algorithm of extraction the feature information in physical STEP AP224file. This program import STEP AP224 file, parse the geometric and topological information, the tolerance data, and feature information line-by-line. After importation and parsing, store data into database. Feature restoration module analyze database including feature information, extract feature information, e.g. feature type, feature's parameter, etc., analyze the relationship and then restore feature to 3D solid model.

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Laver Farm Feature Extraction From Landsat ETM+ Using Independent Component Analysis

  • Han J. G.;Yeon Y. K.;Chi K. H.;Hwang J. H.
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.359-362
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    • 2004
  • In multi-dimensional image, ICA-based feature extraction algorithm, which is proposed in this paper, is for the purpose of detecting target feature about pixel assumed as a linear mixed spectrum sphere, which is consisted of each different type of material object (target feature and background feature) in spectrum sphere of reflectance of each pixel. Landsat ETM+ satellite image is consisted of multi-dimensional data structure and, there is target feature, which is purposed to extract and various background image is mixed. In this paper, in order to eliminate background features (tidal flat, seawater and etc) around target feature (laver farm) effectively, pixel spectrum sphere of target feature is projected onto the orthogonal spectrum sphere of background feature. The rest amount of spectrum sphere of target feature in the pixel can be presumed to remove spectrum sphere of background feature. In order to make sure the excellence of feature extraction method based on ICA, which is proposed in this paper, laver farm feature extraction from Landsat ETM+ satellite image is applied. Also, In the side of feature extraction accuracy and the noise level, which is still remaining not to remove after feature extraction, we have conducted a comparing test with traditionally most popular method, maximum-likelihood. As a consequence, the proposed method from this paper can effectively eliminate background features around mixed spectrum sphere to extract target feature. So, we found that it had excellent detection efficiency.

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Deciphering FEATURE for Novel Protein Data Analysis and Functional Annotation (단백질 구조 및 기능 분석을 위한 FEATURE 시스템 개선)

  • Yu, Seung-Hak;Yoon, Sung-Roh
    • Journal of IKEEE
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    • v.13 no.3
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    • pp.18-23
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    • 2009
  • FEATURE is a computational method to recognize functional and structural sites for automatic protein function prediction. By profiling physicochemical properties around residues, FEATURE can characterize and predict functional and structural sites in 3D protein structures in a high-throughput manner. Despite its effectiveness, it has been challenging to apply FEATURE to novel protein data due to limited customization support. To address this problem, we thoroughly analyze the internal modules of FEATURE and propose a methodology to customize FEATURE so that it can be used for new protein data for automatic functional annotations.

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Simultaneous optimization method of feature transformation and weighting for artificial neural networks using genetic algorithm : Application to Korean stock market

  • Kim, Kyoung-jae;Ingoo Han
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 1999.10a
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    • pp.323-335
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    • 1999
  • In this paper, we propose a new hybrid model of artificial neural networks(ANNs) and genetic algorithm (GA) to optimal feature transformation and feature weighting. Previous research proposed several variants of hybrid ANNs and GA models including feature weighting, feature subset selection and network structure optimization. Among the vast majority of these studies, however, ANNs did not learn the patterns of data well, because they employed GA for simple use. In this study, we incorporate GA in a simultaneous manner to improve the learning and generalization ability of ANNs. In this study, GA plays role to optimize feature weighting and feature transformation simultaneously. Globally optimized feature weighting overcome the well-known limitations of gradient descent algorithm and globally optimized feature transformation also reduce the dimensionality of the feature space and eliminate irrelevant factors in modeling ANNs. By this procedure, we can improve the performance and enhance the generalisability of ANNs.

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Enhancement of Stereo Feature Matching using Feature Windows and Feature Links (특징창과 특징링크를 이용한 스테레오 특징점의 정합 성능 향상)

  • Kim, Chang-Il;Park, Soon-Yong
    • The KIPS Transactions:PartB
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    • v.19B no.2
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    • pp.113-122
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    • 2012
  • This paper presents a new stereo matching technique which is based on the matching of feature windows and feature links. The proposed method uses the FAST feature detector to find image features in stereo images and determines the correspondences of the detected features in the stereo images. We define a feature window which is an image region containing several image features. The proposed technique consists of two matching steps. First, a feature window is defined in a standard image and its correspondence is found in a reference image. Second, the corresponding features between the matched windows are determined by using the feature link technique. If there is no correspondence for an image feature in the standard image, it's disparity is interpolated by neighboring feature sets. We evaluate the accuracy of the proposed technique by comparing our results with the ground truth of in a stereo image database. We also compare the matching accuracy and computation time with two conventional feature-based stereo matching techniques.

Noise-Robust Speaker Recognition Using Subband Likelihoods and Reliable-Feature Selection

  • Kim, Sung-Tak;Ji, Mi-Kyong;Kim, Hoi-Rin
    • ETRI Journal
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    • v.30 no.1
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    • pp.89-100
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    • 2008
  • We consider the feature recombination technique in a multiband approach to speaker identification and verification. To overcome the ineffectiveness of conventional feature recombination in broadband noisy environments, we propose a new subband feature recombination which uses subband likelihoods and a subband reliable-feature selection technique with an adaptive noise model. In the decision step of speaker recognition, a few very low unreliable feature likelihood scores can cause a speaker recognition system to make an incorrect decision. To overcome this problem, reliable-feature selection adjusts the likelihood scores of an unreliable feature by comparison with those of an adaptive noise model, which is estimated by the maximum a posteriori adaptation technique using noise features directly obtained from noisy test speech. To evaluate the effectiveness of the proposed methods in noisy environments, we use the TIMIT database and the NTIMIT database, which is the corresponding telephone version of TIMIT database. The proposed subband feature recombination with subband reliable-feature selection achieves better performance than the conventional feature recombination system with reliable-feature selection.

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Noise Robust Speaker Verification Using Subband-Based Reliable Feature Selection (신뢰성 높은 서브밴드 특징벡터 선택을 이용한 잡음에 강인한 화자검증)

  • Kim, Sung-Tak;Ji, Mi-Kyong;Kim, Hoi-Rin
    • MALSORI
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    • no.63
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    • pp.125-137
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    • 2007
  • Recently, many techniques have been proposed to improve the noise robustness for speaker verification. In this paper, we consider the feature recombination technique in multi-band approach. In the conventional feature recombination for speaker verification, to compute the likelihoods of speaker models or universal background model, whole feature components are used. This computation method is not effective in a view point of multi-band approach. To deal with non-effectiveness of the conventional feature recombination technique, we introduce a subband likelihood computation, and propose a modified feature recombination using subband likelihoods. In decision step of speaker verification system in noise environments, a few very low likelihood scores of a speaker model or universal background model cause speaker verification system to make wrong decision. To overcome this problem, a reliable feature selection method is proposed. The low likelihood scores of unreliable feature are substituted by likelihood scores of the adaptive noise model. In here, this adaptive noise model is estimated by maximum a posteriori adaptation technique using noise features directly obtained from noisy test speech. The proposed method using subband-based reliable feature selection obtains better performance than conventional feature recombination system. The error reduction rate is more than 31 % compared with the feature recombination-based speaker verification system.

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A Study on the Expression of Features Interaction (특징 형상의 간섭 표현에 대한 연구)

  • 김경영;이수홍;고희동;김현석
    • Korean Journal of Computational Design and Engineering
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    • v.2 no.3
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    • pp.142-149
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    • 1997
  • This study is intended to develop a Feature based modeler. It is difficult to integrate CAD and CAM/CAPP with information that is given only by a conventional CAD system. Therefore a lot of studies have concentrated on a Feature based CAD system. But conventional Feature based modelers have had limitation on providing sufficient information related to Feature interaction. If a Feature based modeler is to be used in assembly simulation, a new Feature-based modeling method needs to be developed. Also to support collision detection between parts, we have to handle Feature interaction systematically. Therefore we suggest Cell data structure which handles interaction of Features by volume. The volume created by Feature interaction is saved as a Cell. With the Cell structure we solve problems involved with Feature interaction. This study shows how the Cell data structure can manage Feature interaction and give enough information in assembly simulation.

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The Autonomy of Tenseness as a Feature

  • Yun, Il-Sung
    • Speech Sciences
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    • v.10 no.3
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    • pp.117-131
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    • 2003
  • The feature tenseness has long been a controversial issue. Many scholars have hardly accepted tenseness as a distinctive feature, due to the absence of its consistent and objective phonetic evidence especially in English. Instead, they claim that voicing is the primary feature and even say that no other feature can-be independent of voicing. However, voicing feature does not explain everything and significant aerodynamic and physiological correlates of the feature tenseness have been reported in English as well as in some other languages that have the tense/lax distinction in their obstruents. It is suggested that voicing is a simple and direct feature while tenseness is a complex and indirect feature and its autonomy as a distinctive feature should be acknowledged. This will enable us to describe the phonetic reality more properly across languages as well as in individual languages.

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