• Title/Summary/Keyword: Feature line

검색결과 861건 처리시간 0.021초

STEP-NC의 피쳐 기반 공구경로 생성 및 갱신 (Feature Based Tool Path Planning and Modification for STEP-NC)

  • 조정훈;서석환
    • 한국CDE학회논문집
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    • 제4권4호
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    • pp.295-311
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    • 1999
  • An increasing attention is paid to STEP-NC, the next generation CNC controller interfacing STEP-compatible data. In this paper, we first propose an Architecture for the STEP-NC (called FBCC: Feature Baled CNC Controller) accepting feature code compatible with STEP-data, and executing NC motion feature by feature while monitoring the execution status. The main thrust of the paper has been to develop an automatic on-line tool path generation and modification scheme for milling operation. The tool path it generated iota each feature by decomposing into a finite number of primitive features. The key function in the new scheme is haw to accommodate unexpected execution results. In our scheme, the too1 path plinker is designed to have a tracing capability iota the tool path execution so that a new path can be generated from the point where the operation is stopped. An illustrative example is included to show the capability of the developed algorithm.

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STRENGTH OF THE RAMAN SCATTERED HE II EMISSION LINES IN SYMBIOTIC STARS AND PLANETARY NEBULAE

  • LEE HEE-WON
    • 천문학회지
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    • 제36권2호
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    • pp.55-60
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    • 2003
  • In Lee, Kang & Byun (2001) the discovery of Raman scattered 6545 A feature was reported in symbiotic stars and the planetary nebula M2-9. The broad emission feature around 6545 A is formed as a result of Raman scattering of He II n = 6 $\to$ n = 2 photons by atomic hydrogen. In this paper, we introduce a method to compute the equivalent width of He II $\lambda$ 1025 line and present an optical spectrum of the symbiotic star RR Telescopii as an example for a detailed illustration. In this spectrum, we pay attention to the broad H$\alpha$ wings and the Raman scattered He II 6545 feature. The broad Ha wings are also proposed to be formed through Raman scattering of continuum around Ly$\beta$ by Lee (2000), and therefore we propose that the equivalent width of the He II $\lambda$ 1025 emission line is obtained by a simple comparison of the strengths of the 6545 feature and the broad H$\alpha$ wings. We prepare a template H$\alpha$ wing profile from continuum radiation around Ly$\beta$ with the neutral scattering region that is supposed to be responsible for the formation of Raman scattered He II 6545 feature. Isolation of the 6545 feature that is blended with [N II] $\lambda$ 6548 is made by using the fact that [N II] $\lambda$ 6584 is always 3 times stronger than [N II] $\lambda$ 6548. We also fit the 6545 feature by a Gaussian which has a width 6.4 times that of the He II $\lambda$ 6527 line. A direct comparison of these two features for RR Tel yields the equivalent width $EW_{Hel025} = 2.3{\AA}$ of He II $\lambda$ 1025 line. Even though this far UV emission line is not directly observable due to heavy interstellar extinction, nearby He II lines such as He II $\lambda$ 1085 line may be observed using far UV space instruments, which will verify this calculation and hence the origins of various features occurring in spectra around H$\alpha$.

시각 신경계 반응 모델에 근거한 필기체 off-line 문자에서의 특징 추출 (Feature Extraction of Off-line Handwritten Characters Based on Optical Neural Field)

  • 홍경호;정은화;안병철
    • 한국정보처리학회논문지
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    • 제6권12호
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    • pp.3530-3538
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    • 1999
  • 필기체 오프라인 문자 인식을 위한 특징 추출의 새로군 접근 방법으로, 인간의 시각 신경계의 반응모델에 근거한 특징 추출 방법을 제안한다. 필기체 문자의 특징 추출을 위한 신경망은 평활화 처리, 외곽선 제거, 특징 정보 추출의 3가지 단계로 나누어진다. 필기체 문자에서 발생하기 쉬운 매끄럽지 못한 화소들을 전처리 단계인 평활화 처리를 통해 제거한다. 다음 단계로 인식에 영향을 주지 않는 외곽선 정보를 추출하여 이를 제거한다. 그리고 마지막으로 문자 특징에 해당하는 정보를 추출한다. 제안된 특징 추출 시스템의 타당성을 확인하기 위한 실험은 필기체 오프라인 문자인 PE2 데이터를 사용하였다. 실험을 통해 시각 신경계 반응모델에 근거한 필기체 문자의 특징을 추출하는 시스템은 곡선이나 원, 사각형이 포함된 형태의 필기 문자에서도 특징 추출이 용이하다는 것을 확인할 수 있다.

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MULTILAYER SPECTRAL INVERSION OF SOLAR Hα AND CA II 8542 LINE SPECTRA WITH HEIGHT-VARYING ABSORPTION PROFILES

  • Chae, Jongchul;Cho, Kyuhyoun;Kang, Juhyung;Lee, Kyoung-Sun;Kwak, Hannah;Lim, Eun-Kyung
    • 천문학회지
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    • 제54권5호
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    • pp.139-155
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    • 2021
  • We present an updated version of the multilayer spectral inversion (MLSI) recently proposed as a technique to infer the physical parameters of plasmas in the solar chromosphere from a strong absorption line. In the original MLSI, the absorption profile was constant over each layer of the chromosphere, whereas the source function was allowed to vary with optical depth. In our updated MLSI, the absorption profile is allowed to vary with optical depth in each layer and kept continuous at the interface of two adjacent layers. We also propose a new set of physical requirements for the parameters useful in the constrained model fitting. We apply this updated MLSI to two sets of Hα and Ca II line spectral data taken by the Fast Imaging Solar Spectrograph (FISS) from a quiet region and an active region, respectively. We find that the new version of the MLSI satisfactorily fits most of the observed line profiles of various features, including a network feature, an internetwork feature, a mottle feature in a quiet region, and a plage feature, a superpenumbral fibril, an umbral feature, and a fast downflow feature in an active region. The MLSI can also yield physically reasonable estimates of hydrogen temperature and nonthermal speed as well as Doppler velocities at different atmospheric levels. We conclude that the MLSI is a very useful tool to analyze the Hα line and the Ca II 8542 line spectral daya, and will promote the investigation of physical processes occurring in the solar photosphere and chromosphere.

부분 외곽선 정보를 이용한 이동물체의 추척 알고리즘 (A Study on Tracking Algorithm for Moving Object Using Partial Boundary Line Information)

  • 조영석;이주신
    • 정보처리학회논문지B
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    • 제8B권5호
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    • pp.539-548
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    • 2001
  • 본 연구에서는 배경과 구분되는 이동물체를 추적하기 위한 방법으로 부분 외곽선 정보를 이용한 이동물체 추적 알고리즘을 제안하였다. 이동물체의 추적은 이동물체의 외곽선을 검출한 다음 외곽선 정보를 이동물체의 특징으로 정하여 추적하는 알고리즘을 사용하였다. 먼저 이동물체 외곽선 정보를 이용하여 연속한 동영상 입력에 대하여 속 BMA(Block Matching Algorithm)을 이용하여 움직임 벡터를 추출하고 움직임 벡테를 기초로 이동물체를 추출한다. 다음은 이동물체 초기 특징 벡테 생성단계로서 이동물체에 대한 외곽선을 추출한다. 이동물체의 외곽선 영역 중 상하좌우의 외곽선 일부분을 특징벡터로 정한다. 다음은 추적단계로 이전 프레임에서 얻은 특징벡터를 이용하여 현재 프레임에서 이동물체의 추적을 수행하였다. 제안된 알고리즘에 대하여 실제영상을 가지고 이동물체추적 모의 실험을 수행한 결과 기존 능동 윤곽선 추적알고리즘은 물체 외곽선 전체를 추적하기 때문에 물체의 외곽선 길이에 따라 처리시간이 변화하지만 제안된 알고리즘은 이동물체의 외곽선 영역을 특징정보로 하여 추적하기 때문에 추적연산이 간단하였다. 제안된 이동물체 추적알고리즘 중 이동벡터를 추출하는 BMA 연산은 기존 알고리즘 보다 연산량이 약 39%감소였으며, 상하 좌우 외곽선 정보를 이용하여 이동물체를 추적한 결과 추적오차는 특징벡터의 크기가 [$10{\times}5$]일 때 검색오차가 2화소 이하로 양호하게 나타났다. 또한 기본 능동 윤ㅅ곽선 축적알고리즘은 물체 외곽선 크기에 따른 처리시간이 변화하지만 제안된 알고리즘은 특징벡터의 크기가 일정하기 때문에 동일한 처리시간이 필요하였다.

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자동차 외판 특징선의 시각적 분석을 위한 시편 제작방법 (Methods of Making Samples for a Visual Experiment with Feature Lines of Outer Automotive Panels)

  • 한주호;정연찬
    • 한국생산제조학회지
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    • 제24권4호
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    • pp.455-462
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    • 2015
  • A feature line is a visually noticeable creased line on outer automotive panels. Feature lines play an important role in creating a good impression of a car. Even though the manufacturing quality of feature lines is important, it is difficult to achieve the designed shape owing to the springback of sheet metal. The current study presents five methods of making samples that will be used in a visual experiment to discover a quality control quantitative manufacturing allowance for feature lines. Measurement and inspection methods for the samples are also presented. The results show that plunge machining is the most accurate way to make the desired shape, and that wrapping the machined surface with sheet film is an appropriate way to emulate the roughness and visual texture of the painted outer panels of a car.

Feature-guided Convolution for Pencil Rendering

  • Yang, Hee-Kyung;Min, Kyung-Ha
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제5권7호
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    • pp.1311-1328
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    • 2011
  • We re-render a photographic image as a simulated pencil drawing using two independent line integral convolution (LIC) algorithms that express tone and feature lines. The LIC for tone is then applied in the same direction across the image, while the LIC for features is applied in pixels close to each feature line in the direction of that line. Features are extracted using the coherent line scheme. Changing the direction and range of the LICs allows a wide range of pencil drawing style to be mimicked. We tested our algorithm on diverse images and obtained encouraging results.

소프트웨어 제품라인의 휘처모델과 구성요소간 가변성에 대한 일관성 검증 규칙 (Consistency Checking Rules of Variability between Feature Model and Elements in Software Product Lines)

  • 김세훈;김정아
    • 정보처리학회논문지:소프트웨어 및 데이터공학
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    • 제3권1호
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    • pp.1-6
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    • 2014
  • 모든 기업들은 높은 품질의 정보시스템과 높은 생산성을 가지는 소프트웨어 제품을 만들기 위해 소프트웨어 제품라인 공학(software product line engineering)을 도입하고 있다. 소프트웨어 제품라인 방법론은 다양한 모델들을 가지고 있으며, 각 모델은 추상화 관점과 수준이 서로 다르다. 이러한 모델에 존재하는 요소들간 추적성(traceability)과 가변성(variability) 정보의 일관성(consistency)을 유지하는 것이 중요하다. 본 연구에서는 휘처(feature)의 가변성과 다른 산출물에 정의한 가변성의 일관성을 검증하는 규칙을 제시하였다.

Region Growing Segmentation with Directional Features

  • Lee, Sang-Hoon
    • 대한원격탐사학회지
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    • 제26권6호
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    • pp.731-740
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    • 2010
  • A region merging technique is suggested in this paper for the segmentation of high-spatial resolution imagery. It employs a region growing scheme based on the region adjacency graph (RAG). The proposed algorithm uses directional neighbor-line average feature vectors to improve the quality of segmentation. The feature vector consists of 9 components which includes an observation and 8 directional averages. Each directional average is the average of the pixel values along the neighbor line for a given neighbor line length at each direction. The merging coefficients of the segmentation process use a part of the feature components according to a given merging coefficient order. This study performed the extensive experiments using simulation data and a real high-spatial resolution data of IKONOS. The experimental results show that the new approach proposed in this study is quite effective to provide segments of high quality for the object-based analysis of high-spatial resolution images.

Storage Feature-Based Watermarking Algorithm with Coordinate Values Preservation for Vector Line Data

  • Zhou, Qifei;Ren, Na;Zhu, Changqing;Tong, Deyu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권7호
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    • pp.3475-3496
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    • 2018
  • Most of current watermarking algorithms for GIS vector data embed copyright information by means of modifying the coordinate values, which will do harm to its quality and accuracy. To preserve the fidelity of vector line data and protect its copyright at the same time, a lossless watermarking algorithm is proposed based on storage feature in this paper. Firstly, the superiority of embedding watermark based on storage feature is demonstrated theoretically and technically. Then, the basic concepts and operations on storage feature have been defined including length and angle of the polyline feature. In the process of embedding watermark, the watermark information is embedded into directions of polyline feature by the quantitative mechanism, while the positions of embedding watermark are determined by the feature length. Hence, the watermark can be extracted by the same geometric features without original data or watermark. Finally, experiments have been conducted to show that coordinate values remain unchanged after embedding watermark. Moreover, experimental results are presented to illustrate the effectiveness of the method.