• Journal of the Korean Society of Radiology
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• v.2 no.2
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• pp.17-21
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• 2008

Image quality is improved if the high frequency domains of boundary surface are made distinct. We suggested a method of correcting indistinct defects in ultrasonic images resulting from dynamic imaging. According to the results of the experiment, boundaries in input ultrasonic images became distinct. However, we need to solve the problem that information on pixels of low signal intensity adjacent to boundaries is lost because high-frequency components in the boundaries are strong.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.8
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• pp.1897-1904
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• 1996

This study intends to extract the efficient spectrum characteristics of the fingerpriint image in the fourier domain and to apply them for image enhancement. In order to effectively acquire the spectrum characteristics of the fingerprint in the fourier domain, I set up a 1*64 window as a processing unit and, combining various kinds of the record and overlap lengths, made the power spectrum density estimate for each of those combinations. each spectrum characeristic acquired was applied to a re-synthesis process of the fingerprint image, and, through comparisons and evaluations of the resultant images, an improved gray scale image could be obtained. The validity of this algorithm could be confirmed by the comparison and evaluation fo the binary images which were grained on the established method and the one I used in this experiment.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.2 s.257
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• pp.181-187
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• 2007

Conventional PIV method uses two optical axis configuration during the image grabbing process. That is, the illumination plane and the recording plane must be parallel. This configuration is very natural to grab the whole field without the image distortion. In the real problem, it is often to meet the situation when this configuration is hard to be fulfilled. In the present study, the new PIV method which uses only single optical axis to grab the particle images is developed. This new PIV method becomes possible by utilizing the scanning method similar to the echo PIV technique. One particle image of the scanning PIV consists of scanned several line images and by repeating this scanning process, two particle images were grabbed and processed to produce the velocity vectors. An optimization study was performed to find parameters which minimize the measurement errors. The effects of particle diameter, beam overlap ratio and particle number density were investigated.

• Journal of the Korea Furniture Society
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• v.20 no.5
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• pp.533-542
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• 2009

The space is generally the discontinuation space without being understood agreed by some people. In this time, expressing transparency has various significances in furniture design because modern people want transparence and space due to the complication, numerous unreasonable facts and the lack of honesty in the society. Philip Johnson's Glass House in 1946 influenced architecture, interior, furniture and life article to use transparent materials and space that is being until currently development. The transparency which comes to be preferred clearly means to develop the society continuously. It can be more liberal, honest, and transparent society. The trend appeared in furniture design has meaning as the representative product. This research has perceptional transparency(visible transparency), abstract transparency through space(phenomenal transparency), overlap of surface element, display of line element, image using dot, and changing the image of various spaces.

• Journal of the Semiconductor & Display Technology
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• v.8 no.3
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• pp.45-50
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• 2009

Recently, block-based transforms, like discrete cosine transform (DCT), have been widely used in image and video coding standards, but block-based transforms have a weak point with blocking effect. However, the integer lapped orthogonal transform (ILOT) is a tool for block-based coding with bases functions that overlap near blocks, so it has a strong point against blocking effect. Although it has slightly higher arithmetic complexity than the DCT, the coding gain is significantly higher with much less blocking artifacts. This paper introduces the integer lapped orthogonal transforms and discrete cosine transform. And we compare the performance of DCT with ILOT which is proposed a new efficient method for image coding applications.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.187-194
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• 2011

In this paper, JPEG(Joint Photographic Experts Group) image data video decoding technique is presented, it is Huffman decoding method and fractal image method which is very complexive algorithm and the time required much it to implement this method and the first image is decoded to video frame image. This have defect of overlap decoding and transport work because of impossible to represent objective value of resemblance. The proposed method was calculated the mathematical absolute image resemblance and simplify the moving picture process to reducing the step of moving picture codefying. The results show that smoothed moving picture compared recent methods.

• Investigative Magnetic Resonance Imaging
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• v.19 no.2
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• pp.67-75
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• 2015

Purpose: To investigate the value of image post-processing software (FreeSurfer, IBASPM [individual brain atlases using statistical parametric mapping software]) and inversion time (TI) in volumetric analyses of the hippocampus and to identify differences in comparison with manual tracing. Materials and Methods: Brain images from 12 normal adults were acquired using magnetization prepared rapid acquisition gradient echo (MPRAGE) with a slice thickness of 1.3 mm and TI of 800, 900, 1000, and 1100 ms. Hippocampal volumes were measured using FreeSurfer, IBASPM and manual tracing. Statistical differences were examined using correlation analyses accounting for spatial interpretations percent volume overlap and percent volume difference. Results: FreeSurfer revealed a maximum percent volume overlap and maximum percent volume difference at TI = 800 ms ($77.1{\pm}2.9%$) and TI = 1100 ms ($13.1{\pm}2.1%$), respectively. The respective values for IBASPM were TI = 1100 ms ($55.3{\pm}9.1%$) and TI = 800 ms ($43.1{\pm}10.7%$). FreeSurfer presented a higher correlation than IBASPM but it was not statistically significant. Conclusion: FreeSurfer performed better in volumetric determination than IBASPM. Given the subjective nature of manual tracing, automated image acquisition and analysis image is accurate and preferable.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.789-792
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• 2003

Pipe inspection has a great importance to ensure safety for the nuclear power plant. In this paper, we designed visual inspection module for the tube internal, which diameter is 15${\sim}$20mm. And we made inspection module which consisted of CCD camera and light. And the relation between image and real world coordinate is established. Image processing is performed to calculate mapping parameter and analyze the size of defect. For the calculation of mapping parameter, experiment is performed using grid type test pattern. Acquired image is processed to extract image coordinate. Edge detection, thresholding, median filtering and morphology filtering is applied to extract grid pattern. Extracted image coordinate is used to calculate image to real world mapping. Lens distortion was considered and corrected to get exact data. Coordinate transformation data is provided for the users to recognize easily. Experiment was performed using grid type test pattern, we extracted lens distortion parameter and real coordinate of defect point. Radial distortion of lens was corrected but tangential distortion was not considered. As continuum to this study, the tangential distortion of lens is considered and improvement of analy zing technique for the tube internal be explored continuously.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.229-234
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• 2006

On May 31, 2003. Landsat 7 experienced an anomaly causing the Scan Line Corrector(SLC) to stop functioning normally. The SLC-off causes individual scan lines to alternately overlap and then leave large gaps at the edge of the Image. A many scientists with ongoing experience using ETM+ data evaluated the scientific usability and validity of Landsat 7 products containing the SLC anomaly The best reference scene for gap-filling is the other SLC-on Landsat scene that provide same resolution, few changes, and similar data acquisition. But receiving of Landsat imagery is not stable in Korea. So SPOT image can be another alternative solution because it is a steady-state multispectral satellite image as Landsat image. In this study, we filled the SLC-off gap s of 2, 3, 4 bands using SPOT image by a local regression technique, and assigned the optimum spectral value to gaps of 1, 5, 7 bands based on a spectral adjacency. Through this process, we could restore Landsat SLC-off image and evaluated the accuracy of the results.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.31-34
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• 2003

In this paper, we describe a method for separating text lines in handwritten Korean address images. The most remarkable feature of the proposed method is to use a modified projection technique. named a partial projection technique. A projection based text line separation method which projects the whole address image in horizontal direction to find split points for text line separation cannot avoid failing separation in case of images with a little skew or overlap between vertically neighboring text lines. To overcome this problem, we have introduced a partial projection technique which splits an address image into a few partial address images to be equal width and then project them each horizontally. The experiment done with 989 handwritten Korean address images extracted from live mails shows the superiority of the proposed method. The correct text-line separation rate fir the testing images was about 91.5％.