• Title/Summary/Keyword: image space

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Numerical Evaluation of the Strut Interference and the 3-Run Image method for Wind Tunnel Tests

  • Chang, Byeong-Hee
    • International Journal of Aeronautical and Space Sciences
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    • v.1 no.2
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    • pp.17-21
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    • 2000
  • In order to correct the strut interference in wind tunnel tests, image methods are conventionally used. Because of their excessive extra runs, some alternatives have been tried to reduce the extra runs. In this study, these alternatives were reviewed and checked by the strut interference evaluation with the panel code, CMARC. The present work shows that the strut interference is free from neither model configuration nor model attitude. This dependency makes the alternatives to the image method unfeasible. The 3-run image method was also evaluated. It worked well even for the exaggerated windshield. At this point, reducing the image runs by neglecting parameters affecting minor influence would be best.

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RADIOMETRIC CALIBRATION OF OSMI IMAGERY USING SOLAR CALIBRATION (SOLAR CALIBRAION을 이용한 OSMI 영상자료의 복사 보정)

  • 이동한;김용승
    • Journal of Astronomy and Space Sciences
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    • v.17 no.2
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    • pp.295-308
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    • 2000
  • OSMI(Ocean Scanning Multi-Spectral Imager) raw image data(Level 0) were acquired and radiometrically corrected. We have applied two methods, using solar & dark calibration data from OSMI sensor and comparing with the SeaWiFS data, to the radiometric correction of OSMI raw image data. First, we could get the values of the gain and the offset for each pixel and each band from comparing the solar & dark calibration data with the solar input radiance values, calculated from the transmittance, BRDF (Bidirectional Reflectance Distribution Function) and the solar incidence angle($\beta$, $\theta$) of OSMI sensor. Applying this calibration data to OSMI raw image data, we got the two odd results, the lower value of the radiometric corrected image data than the expected value, and the Venetian Blind Effect in the radiometric corrected image data. Second, we could get the reasonable results from comparing OSMI raw image data with the SeaWiFS data, and get a new problem of OSMI sensor.

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A Study on Improved Codeword Extraction for Decoder of Two Dimensional Barcode PDF417 (PDF417 이차원 바코드 디코더에서 코드워드 추출 알고리즘의 성능 개선에 관한 연구)

  • 정정구;한희일
    • Proceedings of the IEEK Conference
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    • 2002.06d
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    • pp.89-92
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    • 2002
  • In this paper we present a barcode reader to decode two-dimensional symbology PDF-417 and propose a novel method to extract the bar-space patterns directly from the gray-level barcode image, which employs the location and the distance between extreme points of each row of the barcode image. This algorithm proves to be very robust from the high convolution distortion environments such as defocussing and warping, even under badly illuminating condition. If the scanned barcode image is a result of the convolution of a Gaussian-shaped point spread function with a bi-level image, popular image segmentation methods such as image thresholding can not distinguish between very narrow bar-space patterns with a couple of pixels wide. The proposed algorithm shows improved performance over current barcode readers.

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A Study on Speed Improvement of Medical Image Reconstruction Using Limited Range Process (부분영역처리를 이용한 영상재구성의 속도개선에 관한 연구)

  • Ryu, Jong-Hyun;Beack, Seung-Hwa
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.5
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    • pp.658-663
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    • 1999
  • 2D sliced CT images hardly express the human disease in a space. This space expression can be reconstructed into 3D image by piling up the CT sliced image in succession. In medical image, in order to get the reconstructed 3D images, expensive system or much calculation time is needed. But by changing the method of reconstruction procedure and limit the range, the reconstruction time could be reduced. In this study, to reduce the processing time and memory, we suggested a method of interpolation and ray casting processing at the same time in a limited range. Such a limited range processing have advantages that we could reduce the unnecessary interpolation and ray casting. Through a experiment, it is founded that the reconstruction time and the memory was much reduced.

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A Study on the measurement for Vortex trajectory over an UCAV using image processing methods (영상처리기법을 이용한 무인전투기 와류 궤적 계측에 관한 연구)

  • Ko, Ji-Hun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.36 no.6
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    • pp.594-599
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    • 2008
  • Image data produced from ADD water-tunnel test are currently analyzed manually. The accuracy and elapsed time of this process can be determined by observers. In this paper, the algorithm based on MATLAB for improved image data processing and analysis is proposed. This algorithm consists of camera calibration, gray-level transformation, noise filtering and binarization in image preprocessing, vortex trajectory measurement in image analysis. Experimental results show that the proposed algorithm has better accuracy and execution speed than those of the existing methods.

Color Image Coding Based on Shape-Adaptive All Phase Biorthogonal Transform

  • Wang, Xiaoyan;Wang, Chengyou;Zhou, Xiao;Yang, Zhiqiang
    • Journal of Information Processing Systems
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    • v.13 no.1
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    • pp.114-127
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    • 2017
  • This paper proposes a color image coding algorithm based on shape-adaptive all phase biorthogonal transform (SA-APBT). This algorithm is implemented through four procedures: color space conversion, image segmentation, shape coding, and texture coding. Region-of-interest (ROI) and background area are obtained by image segmentation. Shape coding uses chain code. The texture coding of the ROI is prior to the background area. SA-APBT and uniform quantization are adopted in texture coding. Compared with the color image coding algorithm based on shape-adaptive discrete cosine transform (SA-DCT) at the same bit rates, experimental results on test color images reveal that the objective quality and subjective effects of the reconstructed images using the proposed algorithm are better, especially at low bit rates. Moreover, the complexity of the proposed algorithm is reduced because of uniform quantization.

A New Spatial Interpolation Method of GCP Datum of Remote Sensing Images

  • Ren, Liucheng
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1365-1367
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    • 2003
  • A new method, called dynamic space projection method that is suitable to remote sensing image, is adopted to encrypt GCP (ground control point) datum in this paper. The essence of this method is to encrypt enough GCP by using a few known GCP in order to realize the precise correction of remote sensing image. By making use of the method to the GCP datum encrypting and precise geometric correction of TM image and SPOT image, the precision of encrypted GCP is less than one pixel, the precision of precisely corrected image is less than two pixels.

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Triqubit-State Measurement-Based Image Edge Detection Algorithm

  • Wang, Zhonghua;Huang, Faliang
    • Journal of Information Processing Systems
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    • v.14 no.6
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    • pp.1331-1346
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    • 2018
  • Aiming at the problem that the gradient-based edge detection operators are sensitive to the noise, causing the pseudo edges, a triqubit-state measurement-based edge detection algorithm is presented in this paper. Combing the image local and global structure information, the triqubit superposition states are used to represent the pixel features, so as to locate the image edge. Our algorithm consists of three steps. Firstly, the improved partial differential method is used to smooth the defect image. Secondly, the triqubit-state is characterized by three elements of the pixel saliency, edge statistical characteristics and gray scale contrast to achieve the defect image from the gray space to the quantum space mapping. Thirdly, the edge image is outputted according to the quantum measurement, local gradient maximization and neighborhood chain code searching. Compared with other methods, the simulation experiments indicate that our algorithm has less pseudo edges and higher edge detection accuracy.

A Study on the Characteristics of Space Production for Art Museums Reflex Media Art (영상미디어 아트 공간연출 표현특성에 관한 연구 - 미술 전시장을 중심으로 -)

  • Yoo, Jae-Yeup
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2004.05a
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    • pp.156-160
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    • 2004
  • Our time is called as the era of information-oriented society and up-to-date scientific technology, but it can be also called as the era of image. It is because the image has much influence upon our everyday life. In the deluge of images, the delivery of image Is a better and faster synergic tool than the delivery of language, and this trend is consistent with the phases of the times in which the analog modality of synergy is converted into the digital one. The image is a picture that is formed by a physical process, and is all the figures reflected by electronic equipments that reproduce the image. After the discovery of photograph in 1893, the image has been appeared first with the form of movie, and then with the form of TV. However, the appearance of such unidirectional synergic tools as movies and TV. has provided artists with some creative motives with which they intercommunicate their messages via some experimental bidirectional synergic tools. Among image-media arts, the performance of installation and participation is an important example that causes many changes through conceptional conversion, such as the conception of the time in space and formative characteristics. What satisfy this trend have been videos, lasers, holographic, and etc. Furthermore, the appearance of computer has provided a synesthesia, that is, a virtual reality, and mixed a real image with a visional one. The image-media art will realize better synergy through combining brand new machines, informational technology, and art, and have much influence upon our everyday life formatively and artistically in the future. with this study, through analyzing the meaning of relationship between image equipments and space.

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A Robust Staff Line Height and Staff Line Space Estimation for the Preprocessing of Music Score Recognition (악보인식 전처리를 위한 강건한 오선 두께와 간격 추정 방법)

  • Na, In-Seop;Kim, Soo-Hyung;Nquyen, Trung Quy
    • Journal of Internet Computing and Services
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    • v.16 no.1
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    • pp.29-37
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    • 2015
  • In this paper, we propose a robust pre-processing module for camera-based Optical Music Score Recognition (OMR) on mobile device. The captured images likely suffer for recognition from many distortions such as illumination, blur, low resolution, etc. Especially, the complex background music sheets recognition are difficult. Through any symbol recognition system, the staff line height and staff line space are used many times and have a big impact on recognition module. A robust and accurate staff line height and staff line space are essential. Some staff line height and staff line space are proposed for binary image. But in case of complex background music sheet image, the binarization results from common binarization algorithm are not satisfactory. It can cause incorrect staff line height and staff line space estimation. We propose a robust staff line height and staff line space estimation by using run-length encoding technique on edge image. Proposed method is composed of two steps, first step, we conducted the staff line height and staff line space estimation based on edge image using by Sobel operator on image blocks. Each column of edge image is encoded by run-length encoding algorithm Second step, we detect the staff line using by Stable Path algorithm and removal the staff line using by adaptive Line Track Height algorithm which is to track the staff lines positions. The result has shown that robust and accurate estimation is possible even in complex background cases.