• Title/Summary/Keyword: Difference image

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Velocity Estimation of Moving Targets by Azimuth Differentials of SAR Images (SAR 영상의 Azimuth 차분을 이용한 움직이는 물체의 속도측정방법)

  • Park, Jeong-Won;Jung, Hyung-Sup;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.24 no.2
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    • pp.91-98
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    • 2008
  • We present an efficient and robust technique to estimate the velocity of moving targets from a single SAR image. In SAR images, azimuth image shift is a well blown phenomenon, which is observed in moving targets having slant-range velocity. Most methods estimated the velocity of moving targets from the distance difference between the road and moving targets or between ship and the ship wake. However, the methods could not be always applied to moving targets because it is difficult to find the road and the ship wake. We propose a method for estimating the velocity of moving targets from azimuth differentials of range-compressed image. This method is based on a phenomenon that Doppler center frequency shift of moving target causes a phase difference in azimuth differential values. The phase difference is linearly distorted by Doppler rate due to the geometry of SAR image. The linear distortion is eliminated from phase removal procedure, and then the constant phase difference is estimated. Finally, range velocity estimates for moving targets are retrieved from the constant phase difference. This technique was tested using an ENVISAT ASAR image in which several unknown ships are presented. In the case of a isolated target, the result was nearly coincident with the result from conventional method. However, in the case of a target which is located near non-target material, the difference of the result between from our algorithm and from conventional method was more than 1m/s.

Polarimetric SAR Image Classification Based on the Degree of Polarization and Co-Polarized Phase-Difference Statistics (편파화 정도와 동일 편파 위상 차를 이용한 SAR 영상 분류)

  • Chang, Geba;Oh, Yi-Sok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.18 no.12
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    • pp.1345-1351
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    • 2007
  • This paper proposes a polarimetric SAR image classification technique based on the degree of poarization(DoP) and copolarized phase-difference(CPD) statistics. At first, the formulation for the DoP and CPD is derived. Then, the classification technique is verified with the SAR full polarimetric L-band data with consideration of exceptional cases. The technique has capability of classifying SAR data into four major classes, such as bare surface, short-vegetation canopy, tall-vegetation canopy, and village.

Three-Dimensional Map System Using Integral Imaging Technique (집적 영상 기술을 이용한 3차원 지도 시스템)

  • Cho, Myungjin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.11
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    • pp.2799-2804
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    • 2014
  • In this paper, we suggest three-dimensional information extraction map system using integral imaging technique. Integral imaging can record multiple elemental images with different perspectives using a 2D image acquisition device with lenslet array. Using these images, integral imaging can obtain 3D information and display 3D image. In this paper, the position difference between elemental images can be obtained using summation of absolute difference (SAD), and then 3D information can be extracted. Therefore, this technique can find the height information of 3D objects.

The Different Analysis of the Preference and Benefits Sought of Smart Clothing based on Demographic Characteristics (인구통계학적 특성에 따른 스마트 의류에 대한 선호도 및 추구혜택 차이 분석)

  • Park, Younghee
    • Journal of Fashion Business
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    • v.23 no.1
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    • pp.1-13
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    • 2019
  • This study aimed to analyze the preference, the factors of benefits sought, and the difference of benefits sought for smart clothing based on demographic characteristics. This survey study used questionnaire. The subjects of the survey consisted of men and women with ages ranging from twenty to fifty years old, who were living in Gyeongnam region. For the collected data analysis, Factor analysis, t-test, ANOVA, and Duncan multiple range tests were used by SPSS 23. The results obtained were as follows. The different analysis results for smart clothing based on demographic characteristics showed a significant difference with respect to marital status, age, monthly income, and occupation, but showed an insignificant difference with respect to gender. The factors of benefits sought for smart clothing were extracted from five factors-pursuit; image innovation and improvement, pursuit of healthcare, pursuit of body protection, pursuit of amusement and pleasure, and pursuit of hi-tech function. The different analysis results of smart clothing according to demographic characteristics showed a significant difference for pursuit of healthcare only with respect to gender, for pursuit of image innovation and improvement, healthcare, amusement and pleasure, and hi-tech function with respect to marital status, for pursuit of image innovation and improvement, healthcare, amusement and pleasure, and hi-tech function with respect to age, for pursuit of healthcare and body protection with respect to monthly income, and for all five factors with respect to occupation.

A Study of Men's Attitudes toward of their Image Chase (20대 남성이 이미지추구에 관한 연구)

  • Mun, Ji-Young;Kim, Jung-Won
    • Fashion & Textile Research Journal
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    • v.6 no.6
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    • pp.715-722
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    • 2004
  • The social culture critics say that the current situation of the boom in pretty men happened because stereotyped notions of sex roles have changed. However, no scientific study has been done as yet to support this theory. Therefore, this study analyzed the present situation and examined it from many different points of view. I asked 600 men to fill out the questionnaire: 300 from Daegu and the other 300 from Seoul. I analyzed four 461 of them. The inner/outer image of Korean males in their 20s was analyzed into seven factors, a positive image, a progressive image, an affirmative image, a sensible image, an exemplary image, a conscious image, and an active image. The demographic result based on the inner/outer image factors showed a significant difference in ages for a sensible image, a conscious image, and an active image.

Comparative Analysis of Detection Algorithms for Corner and Blob Features in Image Processing

  • Xiong, Xing;Choi, Byung-Jae
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.13 no.4
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    • pp.284-290
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    • 2013
  • Feature detection is very important to image processing area. In this paper we compare and analyze some characteristics of image processing algorithms for corner and blob feature detection. We also analyze the simulation results through image matching process. We show that how these algorithms work and how fast they execute. The simulation results are shown for helping us to select an algorithm or several algorithms extracting corner and blob feature.

A Study on the Optimal Image Acquisition Time of 18F- Flutemetamol using List Mode (LIST mode를 이용한 18F-Flutemetamol 의 최적 영상획득 시간에 관한 연구)

  • Ryu, Chan-Ju
    • Journal of the Korean Society of Radiology
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    • v.15 no.6
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    • pp.891-897
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    • 2021
  • With the development of Amyloid PET Tracer, the accuracy of Alzheimer's diagnosis can be improved through the identification of beta-amyloid neurites. However, the long image acquisition time of 20 minutes can be difficult for the patient. PET/CT scans are sensitive to patient movement and may partially affect test results. In this study, we studied the proper image acquisition time without affecting the quantitative evaluation of the image through the list mode acquisition method according to the time of the distribution of radioactive drugs in the body. The list mode includes information about time compared to the existing frame mode, and it is easy to analyze data because it can reconstruct images about the time that researchers want. The research method obtained a reconstructed image by time using a list mode of 5min frame/bed, 10min frame/bed, 15min frame/bed, and 20min frame/bed to compare the difference between signal-to-pons take ratio (SNR) and lesion-to-pons uptake ratio (LPR) and the difference in reading time to obtain an appropriate image. As a result of quantitative analysis, when measuring in list mode, SUVmean values decreased in 6 regions of interest as the image acquisition time increased, but showed the largest difference in 5 min/bed images, followed by 10 min/bed and 15 min/bed. As a result, the difference in SUVmean values decreased. Therefore, it was found that SUVmean values at 15 min/bed did not differ enough to not affect image evaluation. There was no difference in LPR values. As a result of the qualitative analysis, there was no change in the reading findings according to the PET image acquisition time and there was no significant difference in the qualitative analysis score of the image reconstruction according to time. As a result of the study, there is no significant difference between 15 min/bed and 20 min/bed images during the 18F-flutemetamol PET/CT test, so it can be said that it is clinically useful to reduce the image acquisition time selectively using 15 min/bed via list mode depending on the patient's condition.

Evaluation of Image Segmentation Techniques (영상 분할 방법의 평가)

  • Lee, Sung-Ki;Kim, Hyo-Sun
    • The Transactions of the Korea Information Processing Society
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    • v.2 no.4
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    • pp.524-534
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    • 1995
  • Image segmentation is a process of partitioning of an image into different regions that have similar properties. It is an old and difficult problem. They have developed many image segmentation systems and have studied to evaluate the existing segmentation systems. However, evaluation of image segmentation systems is very difficult in nature. In this paper, we propose the evaluation criteria that evaluate image segmentation systems automatically. In order to overcome the drawbacks of using only a single evaluation criterion, we have incorporated four evaluation criteria, that is, boundary difference, boundary consistency, region uniformity, and region difference. As the experimental results show, our evaluation criteria performs very well.

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Object Tracking using Adaptive Template Matching

  • Chantara, Wisarut;Mun, Ji-Hun;Shin, Dong-Won;Ho, Yo-Sung
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.1
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    • pp.1-9
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    • 2015
  • Template matching is used for many applications in image processing. One of the most researched topics is object tracking. Normalized Cross Correlation (NCC) is the basic statistical approach to match images. NCC is used for template matching or pattern recognition. A template can be considered from a reference image, and an image from a scene can be considered as a source image. The objective is to establish the correspondence between the reference and source images. The matching gives a measure of the degree of similarity between the image and the template. A problem with NCC is its high computational cost and occasional mismatching. To deal with this problem, this paper presents an algorithm based on the Sum of Squared Difference (SSD) and an adaptive template matching to enhance the quality of the template matching in object tracking. The SSD provides low computational cost, while the adaptive template matching increases the accuracy matching. The experimental results showed that the proposed algorithm is quite efficient for image matching. The effectiveness of this method is demonstrated by several situations in the results section.

The Difference of Perception of High School Girl Image according to Hair Style and Perceiver's Generation

  • Kim, Youngok;Lee, Eunsil
    • Journal of Fashion Business
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    • v.18 no.6
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    • pp.208-221
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    • 2014
  • The purpose of this study was to investigate the effects of the hair style, and perceiver's generation on the perception of a high schoolgirl's image. A quasi-experimental method by questionnaire was used. The subjects were 253 high schoolgirls and their mothers living in Jinju. The data were analyzed by using frequency, factor analysis, Cronbach's alpha-reliability coefficient, three-way ANOVA, and Duncan's multiple ranges test. The high schoolgirl's image was derived in five dimensions by factor analysis: schoolgirl look, prettiness, individuality, activeness, and cuteness. In the image based on the hair length, it was assessed that the short cut and the bobbed hair styles looked more like school girls. And the short cut and long hair styles were considered as showing individuality. On the other hand, the bobbed hair style was assessed as cuter than styles of other lengths. For the bangs, the short bangs were found to more school-girl look and cuter than the long bangs. The mother group, whose ages were older than that of the other group, evaluated that the stimulative pictures had more school-girl look, individuality, prettiness, activeness and cuteness, compared to how the school girl group evaluated. It was shown that the generation gap produced different opinions about the stimulative pictures. Therefore hair style, bangs style, and difference in generations were found to be the variables affecting perception of high school girl image.