• 제목/요약/키워드: Image Transformation

검색결과 1,071건 처리시간 0.023초

레이저 스페클간섭법에 의한 STS430의 열팽창계수 측정 (Thermal Expansion Coefficient Measurement of STS430 by Laser Speckle Interferometry)

  • 김경석;이항서;정현철;양승필
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.29-33
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    • 2004
  • This paper presents ESPI system for the measurement of thermal expansion coefficient of STS430 up to 1,000$^{\circ}C$. Existing methods, strain gauge and moire have the limitation of contact to object and do not supply the coefficient up to 800$^{\circ}C$. There needs to measure the data up to 800$^{\circ}C$, because heat resistant materials have high melting temperature up to 1,000$^{\circ}C$. In previous studies related to thermal strain analysis, the quantitative results are not reported by ESPI at high temperature, yet. In-plane ESPI and vacuum chamber for the reduction of air turbulence and oxidation are designed for the measurement of the coefficient up to 1,000$^{\circ}C$and speckle correlation fringe pattern images are processed by commercial image filtering tool-smoothing, thinning and enhancement- to obtain quantitative results, which is compared with references data. The comparison shows two data are agreed within 4.1% blow 600$^{\circ}C$ however, there is some difference up to 600$^{\circ}C$. Also, the incremental ratio of the coefficient is changed up to 800$^{\circ}C$. The reason is the phase transformation of STS430 probably begins at 800$^{\circ}C$.

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임의 색온도에 대한 조명 색 변환기법 (Transformation of Illuminant Chromaticity for Arbitrary Color Temperature)

  • 김정엽;김상현;현기호
    • 한국멀티미디어학회논문지
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    • 제7권10호
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    • pp.1370-1377
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    • 2004
  • 동일한 장면을 다양한 조건에서 촬영한 영상이나 비디오는 서로 다른 색감을 가지며 촬영 조건에서 중요한 역할을 하는 것은 현장의 조명이다. 조명의 색온도에 따라 전체적인 색감이 결정되므로 조명색의 변환방법이 필요하다. 본 논문에서는 임의로 지정된 색온도로의 조명색 변환 방법을 제안한다. 기존의 조명색 변환 방법은 미리 정해진 일정한 개수의 대표성이 있는 색온도에 대한 변환 관계를 미리 계산하여 두었다가 활용하는 정도이다. 제안한 방법은 임의로 지정한 기준과 목표로 하는 색온도에 대한 변환 관계를 직접적으로 구하여 적용할 수 있는 장점이 있다.

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범용 3D 그래픽 엔진의 GIS 정보 서비스를 위한 데이터 자동변환 알고리즘 개발 (Development of Data Automation Algorithm for GIS Service in Universal 3D Graphics Engine)

  • 김형훈;박현철;최형욱;강수명;정윤재
    • 한국멀티미디어학회논문지
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    • 제20권3호
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    • pp.581-592
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    • 2017
  • Geographic Information System (GIS) is a method of expressing objects in a space. Currently, many research and developments are being conducted to implement 3D GIS. In previous studies, 3D GIS applications have been developed using Unity 3D, which is a 3D engine with good development accessibility. However, it requires manual work to enter various formats of GIS data, making it difficult to immediately reflect GIS data that change frequently. To improve this problem, this study developed a method for automatically reading and outputting various GIS data from the existing Unity 3D application. The improved application could read Satellite Images, Aerial Photographs, Digital Elevation Models (DEM) and Shapefiles with no transformation through other commercial programs, and they could be implemented as 3D objects. This study automated the GIS data conversion which had been manually performed and as a result, the manpower, time, and resources required for 3D GIS implementation can be saved.

He-Ne 레이저와 CCD 카메라를 이용한 비접촉 3차원 측정 (Noncontact 3-dimensional measurement using He-Ne laser and CCD camera)

  • 김봉채;전병철;김재도
    • 대한기계학회논문집A
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    • 제21권11호
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    • pp.1862-1870
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    • 1997
  • A fast and precise technique to measure 3-dimensional coordinates of an object is proposed. It is essential to take the 3-dimensional measurements of the object in design and inspection. Using this developed system a surface model of a complex shape can be constructed. 3-dimensional world coordinates are projected onto a camera plane by the perspective transformation, which plays an important role in this measurement system. According to the shape of the object two measuring methods are proposed. One is rotation of an object and the other is translation of measuring unit. Measuring speed depending on image processing time is obtained as 200 points per second. Measurement resolution i sexperimented by two parameters among others; the angle between the laser beam plane and the camera, and the distance between the camera and the object. As a result of these experiments, it was found that measurement resolution ranges from 0.3mm to 1.0mm. This constructed surface model could be used in manufacturing tools such as rapid prototyping machine.

아르누보의 장식화 공간에 관한 연구 (A Study on Ornamental Space in Art Nouveau Style)

  • 김성혜
    • 한국실내디자인학회논문집
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    • 제14권1호
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    • pp.56-63
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    • 2005
  • This study aims to understand the ornamental space in Art-Nouveau style which was made up the ornamental aspect and spatial aspect. So that It is needed to classify the ornamental space into three categories according to the way of construction; pictorial composition, non-objective composition and organic construction. To find the meaning of these ornamental spaces, works of Art-Nouveau are analyzed into ornament and space, in result we know that process of integration, relativity of ornament as a part and forms of expression in ornamental space have some regulation; use of natural motive, repetition of image and organic combination. Whereas the ornamental space in Art-Nouveau style has comprehensive capacity between antagonistic relations just like tradition and new mechanism, the space could receive a lot of different ideas and express these ideas as ornaments. Although the ornamental space also had weak points which were the lack of transformation and the difficulties of the application of other design due to the perfection itself, we could create new space which meets the requirements of the times, if we develop and make up for the weak points in the ornamental space under the principles of dialectic.

3차원 정보 제공을 위한 X-선 검색장치의 기하학적 모델링 (The Geometric Modeling for 3D Information of X-ray Inspection)

  • 이흥호;이승민
    • 전기학회논문지
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    • 제62권8호
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    • pp.1151-1156
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    • 2013
  • In this study, to clearly establish the concept of a geometric modeling I apply for the concept of Pushbroom, limited to two-dimensional radiation Locator to provide a three-dimensional information purposes. Respect to the radiation scanner Pushbroom modeling techniques, geometric modeling method was presented introduced to extract three-dimensional information as long as the rotational component of the Gamma-Ray Linear Pushbroom Stereo System, introduced the two-dimensional and three-dimensional spatial information in the matching relation that can be induced. In addition, the pseudo-inverse matrix by using the conventional least-squares method, GCP(Ground Control Point) to demonstrate compliance by calculating the key parameters. Projection transformation matrix is calculated for obtaining three-dimensional information from two-dimensional information can be used as the primary relationship, and through the application of a radiation image matching technology will make it possible to extract three-dimensional information from two-dimensional X-ray imaging.

웨이블릿 변환 기반의 컬러 영상에 대한 디지털 워터마킹 (Digital Watermarking based on Wavelet Transform for Color Images)

  • 박영일;김석태
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2007년도 춘계종합학술대회
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    • pp.127-130
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    • 2007
  • 본 논문에서는 컬러 영상에 대한 웨이블릿 변환 기반의 디지털 워터마킹을 하는 새로운 기법을 제안한다. 먼저 워터마크에 대해 Arnold 변환을 하여 워터마크의 상관성을 적게 만든다. 그 후, 선형 비트확장 기법을 적용하여 확대된 워터마크를 웨이블릿 변환 된 컬러 영상의 Y 영역의 저주파대에 일정한 강도로 삽입한다 워터마크를 추출 할 때는 F-노름 (norm)함수를 이용한다. 다양한 컬러 영상에 대해 실험한 결과 제안방법은 충실도와 강인성 측면에서 우수한 특성을 가짐을 확인하였다.

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테라헤르츠 전자기파 펄스의 변조를 이용한 이미징의 해상도 연구 (Imaging with terahertz electromagnetic pulses)

  • 오승재;강철;손주혁
    • 한국광학회지
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    • 제15권1호
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    • pp.46-50
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    • 2004
  • 테라헤르츠 전자기파 펄스(테라파)의 변조를 통하여 주파수별 영상을 얻었다. 갈바노미터를 이용한 고속훑기방법으로 시간축 신호를 실시간으로 획득하였고, 이를 fast Fourier transformation을 통하여 주파수별 신호로 변환하였다. 테라파 접속지점에서 파의 공간 분포를 주파수별로 얻었으며 주파수가 증가할수록 집속직경이 축소됨을 확인하였다. 이 접속지점에서 1차원과 2차원 시료를 이동시킴으로써 각각의 주파수별 영상을 얻었고 주파수가 증가할수록 영상의 해상도가 증가함을 확인하였다. 또한 가려진 시료에 테라파를 투과시킴으로써 비파괴영상을 얻었다.

DCT를 사용한 디지털 하프토닝 (Digital Halftoning using DCT)

  • 권영만;김규호;권형준
    • 한국인터넷방송통신학회논문지
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    • 제13권6호
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    • pp.79-85
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    • 2013
  • 이 논문에서는 먼저 디지털 하프토닝 영상을 생성하는 기존의 방법들과 DCT 변환에 대해서 설명한다. 그런후에 DCT 변환에 근간을 둔 새롭고 단순한 하프토닝 알고리즘을 제안한다. 이 논문은 제안한 알고리즘을 검정하기 위해서 실현 가능성 검증을 수행한다. 그래서 DCT 계수의 가중치를 조절하여 생성된 여러 가지 영상들을 평가하였다. 실험을 통해서 단순한 이상적인 계단 함수 형태의 가중치를 사용하는 것보다는 램프 함수 형태의 가중치를 사용하면 더 좋은 결과를 얻었다. 단순한 응용분야로서 MPEG 비디오에 제안한 알고리즘을 적용하여 하프토닝 비디오를 생성할 수 있다.

다중선형회귀모델을 이용한 움직임 추정방법 (Motion estimation method using multiple linear regression model)

  • 김학수;임원택;이재철;이규원;박규택
    • 전자공학회논문지S
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    • 제34S권10호
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    • pp.98-103
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    • 1997
  • Given the small bit allocation for motion information in very low bit-rate coding, motion estimation using the block matching algorithm(BMA) fails to maintain an acceptable level of prediction errors. The reson is that the motion model, or spatial transformation, assumed in block matching cannot approximate the motion in the real world precisely with a small number of parameters. In order to overcome the drawback of the conventional block matching algorithm, several triangle-based methods which utilize triangular patches insead of blocks have been proposed. To estimate the motions of image sequences, these methods usually have been based on the combination of optical flow equation, affine transform, and iteration. But the compuataional cost of these methods is expensive. This paper presents a fast motion estimation algorithm using a multiple linear regression model to solve the defects of the BMA and the triange-based methods. After describing the basic 2-D triangle-based method, the details of the proposed multiple linear regression model are presented along with the motion estimation results from one standard video sequence, representative of MPEG-4 class A data. The simulationresuls show that in the proposed method, the average PSNR is improved about 1.24 dB in comparison with the BMA method, and the computational cost is reduced about 25% in comparison with the 2-D triangle-based method.

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