• 제목/요약/키워드: contours

검색결과 754건 처리시간 0.023초

Circular-to-Rectangular Transition Duct 에서의 3차원 유동장에 관한 연구 (Three-Dimensional Numerical Simulation on a Circular-to-Rectangular Transition Duct)

  • 조수용;손호재
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 1998년도 추계 학술대회논문집
    • /
    • pp.55-61
    • /
    • 1998
  • The purpose of this study is to compare the predictive behaviors of the extended $k-{\varepsilon}$ turbulence model and the standard $k-{\varepsilon}$ turbulence model. Grid dependency is tested with the H-type grid and the O-type grid. Computations have been performed for a circular-to-rectangular transition duct. Numerical results for several sections along the streamwise have been obtained to compare with experimental results. The Reynolds number is 390,000 based on the bulk velocity at the inlet. The computed axial velocity contours, transverse velocity profiles, static pressure contours, peripheral skin friction coefficient, and peripheral wall static pressure distributions have been compared with experimental results. The computed results obtained with the extended $k-{\varepsilon}$ turbulence model show better agreement with experimental results than those obtained with the standard $k-{\varepsilon}$ turbulence model. Comparing to the computed results obtained with the H-type grid and O-type grid, those with H-type grid agree well with experimental results.

  • PDF

Circular-to-Rectangular Transition Duct 내부의 3차원 유동장에 관한 연구 (Three-Dimensional Numerical Simulation within a Circular-to-Rectangular Transition Duct)

  • 조수용;정희택;손호재
    • 한국전산유체공학회지
    • /
    • 제3권2호
    • /
    • pp.9-16
    • /
    • 1998
  • Predictive behaviors by the extended k-${\varepsilon}$ turbulence model and the standard k-${\varepsilon}$ turbulence model are compared. Grid dependency is tested with the H-type grid as well as the O-type grid. Computations have been performed on a circular-to-rectangular transition duct. The Reynolds number is 390,000 based on the bulk velocity at the inlet. The computed axial velocity contours, transverse velocity profiles, static pressure contours, peripheral skin friction coefficient, peripheral wall static pressure distributions and turbulence kinetic energy have been compared with experimental results. The computed results than those obtained with the standard k-${\varepsilon}$ turbulence model. Comparing to the computed results obtained with the H-type grid and O-type grid, those with H-type grid seem to agree well with experimental results.

  • PDF

뷰티 메이크업을 위한 컴퓨터 그래픽스 활용에 관한 연구 (A study of Beauty Make-up Using Computer Graphics)

  • 권현아
    • 한국의류산업학회지
    • /
    • 제8권2호
    • /
    • pp.214-224
    • /
    • 2006
  • Computer graphics mean a reproduction of various information through image processing or the technology that is widely thought in makeup areas also, recently. Especially, Adobe Illustrator, unlike Adobe Photoshop used in image editing and correction, is software suitable for image drawing and reproducing beauty makeup. Beauty makeup is a work adorning human body to fit to the aesthetic standard in that period, and is a plastic art expressing shapes, colors and textures using design elements. Adobe Illustrator is a 2D graphics designing images using shapes having plane colors. In this study I studied techniques reproducing each element of contours and colors of beauty makeup through Adobe Illustrator CS. In other words, I have prepared a reference data by studying techniques reproducing beauty makeup using Adobe Illustrator CS. In this study, though, I couldn't try various things, because I limited facial contour and skin color to only one kind. Therefore, I hope, in the future, others can expand the ethnics of using Adobe Illustrator in more enriched ways by working on various facial contours and skin colors.

억양의 의사소통적 기능에 대한 연구: 일어문 시기의 아동을 대상으로 (A Study on the Communicative Functions of Prosodic Contours: in Children with Single Word Sentences)

  • 안미리;김태경
    • 음성과학
    • /
    • 제11권2호
    • /
    • pp.151-164
    • /
    • 2004
  • This study examined the use of intonation in children with single word sentences and investigated the communicative functions of pitch range and pitch direction. Two children aged 13months were observed in interaction with their mothers for 10 months. The vocalizations were coded separately for communicative function and for prosodic feature. Results show that level tones are used most frequently, and pitch range is higher for request than declaration or answer and lower for answer than request or declaration. And trends in prosodic contours were observed in request, declaration, and answer respectively. For one child, rising tones were frequently associated with request whereas rising-falling tone with declaration. For the other child, rising-level tones were more frequently associated with request whereas falling-level appeared more often in conjunction with declaration. These trends appeared more distinct in proportion as they grow in months. This result indicate that the way to express communicative functions transfer gradually from differentiating pitch range to diversify pitch direction.

  • PDF

Graphical Video Representation for Scalability

  • Jinzenji, Kumi;Kasahara, Hisashi
    • 한국방송∙미디어공학회:학술대회논문집
    • /
    • 한국방송공학회 1996년도 Proceedings International Workshop on New Video Media Technology
    • /
    • pp.29-34
    • /
    • 1996
  • This paper proposes a new concept in video called Graphical Video. Graphical Video is a content-based and scalable video representation. A video consists of several elements such as moving images, still images, graphics, characters and charts. All of these elements can be represented graphically except moving images. It is desirable to transform these moving images graphical elements so that they can be treated in the same way as other graphical elements. To achieve this, we propose a new graphical representation of moving images using spatio-temporal clusters, which consist of texture and contours. The texture is described by three-dimensional fractal coefficients, while the contours are described by polygons. We propose a method that gives domain pool location and size as a means to describe cluster texture within or near a region of clusters. Results of an experiment on texture quality confirm that the method provides sufficiently high SNR as compared to that in the original three-dimensional fractal approximation.

  • PDF

Adaptive Active Contour Model: a Localized Mutual Information Approach for Medical Image Segmentation

  • Dai, Shuanglu;Zhan, Shu;Song, Ning
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제9권5호
    • /
    • pp.1840-1855
    • /
    • 2015
  • Troubles are often met when traditional active contours extract boundaries of medical images with inhomogeneous bias and various noises. Focusing on such a circumstance, a localized mutual information active contour model is discussed in the paper. By defining neighborhood of each point on the level set, mutual information is introduced to describe the relationship between the zero level set and image field. A driving energy term is then generated by integrating all the information. In addition, an expanding energy and internal energy are designed to regularize the driving energy. Contrary to piecewise constant model, new model has a better command of driving the contours without initialization.

중국인 학습자들의 한국어 강세구 실현양상과 오류진단 및 교정방안 연구 (A Study on the Detection and the Correction of Prosodic Errors Produced by Chinese Korean-Learners)

  • 윤영숙
    • 말소리와 음성과학
    • /
    • 제4권2호
    • /
    • pp.51-59
    • /
    • 2012
  • The purpose of this study is to examine the pitch pattern of Korean accentual phrases produced by Chinese Korean-learners in the reading of a Korean text. Korean accentual phrase is determined by a specific F0 contour. And the pitch contour of APs differ depending on their length and the nature of initial segment. In order to examine if Chinese speakers are also aware such a phonetic properties, we have examined the AP pitch contours produced by 15 Chinese speakers differing in proficiency, and compared them to pitch contours produced by six Korean native speakers. The results show that Chinese speakers' pitch errors were observed in initial segment-tone interaction and in type of pitch patterns. However, even though Chines speakers produced the same type of pitch patterns, internal tonal modulation differs from native speakers. Finally, on the basis of theses results, we proposed a teaching method that visualizes the F0 contour.

Development of an Automatic Program to Analyze Sunspot Groups on SOHO/MDI Continuum Images using OpenCV

  • Park, Jong-Yeob;Moon, Yong-Jae;Choi, Seong-Hwan
    • 천문학회보
    • /
    • 제36권2호
    • /
    • pp.102.2-102.2
    • /
    • 2011
  • Sunspots usually appear in a group which can be classified by certain morphological criteria. In this study we examine the moments which are statistical parameters computed by summing over every pixels of contours, in order to quantify the morphological characteristics of a sunspot group. The moments can be additional characteristics to the sunspot group classification such as McIntosh classification. We are developing a program for image processing, detection of contours and computation of the moments using continuum images from SOHO/MDI. We apply the program to count the sunspot numbers from 303 continuum images in 2003. The sunspot numbers obtained by the program are compared with those by SIDC. The comparison shows that they have a good correlation (r=89%). We are extending this application to automatic sunspot classification (e.g., McIntosh classification) and flare forecasting.

  • PDF

Contourlet 변환을 이용한 새로운 압축방법에 대한 연구 (The study of New Compression method using Contourlet transform)

  • 정현진;장준호;김영섭
    • 반도체디스플레이기술학회지
    • /
    • 제6권3호
    • /
    • pp.55-59
    • /
    • 2007
  • Wavelet Transform is amenable to efficient algorithms. So wavelet transform was adopted many signal processing and communication applications. For example, the wavelet transform was adopted as the transform for JPEG2000. However, Wavelet has weakness about smoothness along the contours and limited directional information. Hence, recently, some new transforms have been introduced to take advantage of this property. So we use to other transform, called contourlet transform in compression. In this paper, we propose a new method for image compression based on the contourlet transform, which has been recently introduced. Contourlet transform has a good result about images with smooth contours. Moreover, Contourlet is feasible multiresolution and multidirection expansion using non-separable filter bank. This treatise shows a good image representation after compressing using contourlet transform.

  • PDF

선형 터빈케스케이드 끝벽의 열전달 특성에 관한 연구 (An Experimental Investigation of the Heat Transfer Characteristics on the Endwall Surface Within the Plane Turbine Cascade)

  • 양장식;나종문;이기백
    • 대한기계학회논문집
    • /
    • 제19권9호
    • /
    • pp.2386-2398
    • /
    • 1995
  • The paper describes the results of an experimental investigation of the heat transfer rate on the endwall surface within the plane turbine cascade passage and includes the effect of the heat transfer for the two different boundary layer thicknesses and Reynolds numbers. The limiting streamlines on the endwall surface have been visualized by the oil film method in order to compare with the endwall heat transfer. The hue-capturing method using the termochromatic liquid crystals with great spatial resolution has been used to provide the local distribution of the endwall heat transfer coefficients. Because the detailed contours of the local heat transfer coefficients over the entire endwall can be obtained from the hue-capturing method, it has been possible to obtain information on the endwall heat transfer within the plane turbine cascade passage from these heat transfer contours.