• Title/Summary/Keyword: Image difference

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Design and Implementation of the Security System for the Moving Object Detection (이동물체 검출을 위한 보안 시스템의 설계 및 구현)

  • 안용학;안일영
    • Convergence Security Journal
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    • v.2 no.1
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    • pp.77-86
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    • 2002
  • In this paper, we propose a segmentation algorithm that can reliably separate moving objects from noisy background in the image sequence received from a camera at the fixed position. Image segmentation is one of the most difficult process in image processing and an adoption in the change of environment must be considered for the increase in the accuracy of the image. The proposed algorithm consists of four process : generation of the difference image between the input image and the reference image, removes the background noise using the background nois modeling to a difference image histogram, then selects the candidate initial region using local maxima to the difference image, and gradually expanding the connected regions, region by region, using the shape information. The test results show that the proposed algorithm can detect moving objects like intruders very effectively in the noisy environment.

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Detection of Surface Water Bodies in Daegu Using Various Water Indices and Machine Learning Technique Based on the Landsat-8 Satellite Image (Landsat-8 위성영상 기반 수분지수 및 기계학습을 활용한 대구광역시의 지표수 탐지)

  • CHOUNG, Yun-Jae;KIM, Kyoung-Seop;PARK, In-Sun;CHUNG, Youn-In
    • Journal of the Korean Association of Geographic Information Studies
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    • v.24 no.1
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    • pp.1-11
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    • 2021
  • Detection of surface water features including river, wetland, reservoir from the satellite imagery can be utilized for sustainable management and survey of water resources. This research compared the water indices derived from the multispectral bands and the machine learning technique for detecting the surface water features from he Landsat-8 satellite image acquired in Daegu through the following steps. First, the NDWI(Normalized Difference Water Index) image and the MNDWI(Modified Normalized Difference Water Index) image were separately generated using the multispectral bands of the given Landsat-8 satellite image, and the two binary images were generated from these NDWI and MNDWI images, respectively. Then SVM(Support Vector Machine), the widely used machine learning techniques, were employed to generate the land cover image and the binary image was also generated from the generated land cover image. Finally the error matrices were used for measuring the accuracy of the three binary images for detecting the surface water features. The statistical results showed that the binary image generated from the MNDWI image(84%) had the relatively low accuracy than the binary image generated from the NDWI image(94%) and generated by SVM(96%). And some misclassification errors occurred in all three binary images where the land features were misclassified as the surface water features because of the shadow effects.

Body Image, Self-esteem and Depression in College Female Students - Normal and Overweight - (정상체중과 과체중 여대생의 신체상, 자아존중감 및 우울에 관한 연구)

  • 신혜숙;백승남
    • Journal of Korean Academy of Nursing
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    • v.33 no.3
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    • pp.331-338
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    • 2003
  • Purpose: The purpose of this study was to investigate the relationships among variables of body image, self-esteem and depression in college female students according to the normal and overweight. Method: The subjects of this study consisted of 245 college female students. The data was collected through personal interviews using questionnaires from May to June of 2001. The data was analyzed by the SPSS computer program, and it included descriptive statistics, x$^2$-test, t-test and the pearson correlation coefficient. Result: Demographics provided a significant difference in grade, household income, weight control experience. There was a perceived health status difference, according to the normal and overweight subjects. There was a significant difference in body image, self-esteem and depression between the two groups. There was a significant positive correlation between body image and self-esteem, and negative correlation between body image and depression, and self-esteem and depression in college female students. Conclusion: The Findings of this study give useful information to construct further studies in intervention program relating overweight control for college female students.

Vision Sensor System for Weld Seam Tracking of I-Butt Joint with Height Variation (높이 변화가 있는 막대기 용접선 추적용 시각센서)

  • Kim Moo-Yeon;Kim Jae-Woong
    • Journal of Welding and Joining
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    • v.22 no.6
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    • pp.43-49
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    • 2004
  • In this study, a visual sensor system which can detect I-butt weld joint with height variation and includes a seam tracking algorithm was investigated. Three-dimensional position of an object can be acquired by using the method of distance measurement, i.e., an optical trigonometry which results from the spatial relations between the camera, the object and the structured light by a visible laser. Effects of laser intensity and iris number for the image quality as well as object material were investigated for the optical system design. For the image processing, a region of interest is defined from the whole image and a line image of laser is drew by using the gray level difference in the image. From the drew laser line, the weld joint can be recognized in searching the biggest point position calculated from the central difference method. Through a series of welding experiments, a good tracking performance was confirmed under GMA welding.

The Effect of Supportive Group Nursing Care on Body Image of the Patient With tower Limb Fracture (지지적 집단간호가 하지골절 환자의 신체상(Body Image)에 미치는 영향)

  • 정추자
    • Journal of Korean Academy of Nursing
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    • v.15 no.3
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    • pp.74-80
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    • 1985
  • This study was attempted to identify the difference between body image of the patients with lower limb fracture and that of normal persons, and to examine if supportive group care could offer an apportunity for positive change in body image of the patient with lower limb fracture under the Quasi-experimental design. The subjects for this study were obtained by ta-king convenient sample of soldiers; the experimental group were 44 lower limb fractured patients hospitalized on the orthopedic Surgery unit in S Army General Hospital, while the control group were 44 normal enlisted men serving in the B Army regiment. Supportive group nursing care was given to the lower limb fractured patients who belong to the experimental group. Pre-and post-tests were administered to the experimental and the control group. The instruments to measure body image of the subjects were body Cathexis Scale developed by Scord and Jourard (1953) and Body Meaning Scale dove-loped by the reseacher. The reliability coefficients by Cronhach's u-test were .95 in body Cathexis Scale and .89 in Body Meaning Scale in this study. Data for this study were collected over a period 12 days from the 12th to the 24th of October, 1984 by the questionnaire. Data were analyzed by computer. Frequency, Percentage and x²-test were used to examine general chacteristics of the subjects. t-test was used to analyze the hypotheses. Analysis of variance was used to test difference in body image between groups classified by the general characteristics. Pearson Correlation Coefficient was used to identify the correlation between Body Cathexis Scale and Body Cathexis Scale and Body Meaning Scale. The results of this study were as follows: 1. No significant difference was found between the experimental and the control group on general characteristics of the subjects (p> .05). 2. Hypothesis I:“There will be a difference in body image between patiens with lower limb fracture and normal persons,”was supported(Body Cathexis t=6.91, p<.001, Body Meaning t=5.66, p< .001). 3. Hypothesis Ⅱ;“The will be a difference in body image of patients with lower limb fracture bet-ween after and before, supportive group nursing care was provided,”was supported (Body Cathexis t=5.90, p<.001, Body Meaning t=4.45, p <.001). 4. There was no significant difference in body image between groups classified by the general characteristics (p> .05). 5. The correlation between Body Cathexis Scale and Body Meaning Scale: It was reported that Body Cathexis Scale correlated with Body Meaning Scale in total subjects of the experimental and control group (r=.744, p<.001). That is, there was relatively high correlation between two scales. body Cathexis Scale correlated with Body Meaning Scale in the experimental group(r=.738, p <.001) and in the control group (r=.352, p <.001). That is, there was more than moderate correlation between two scales. In conclusion, it was found that there was a difference in body image between patients with lower limb fracture and normal persons, and supportive group nursing care offered an opportunity for positive change in body image of the patient with lower limb fracture.

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Low Contrast and Low kV CTA Before Transcatheter Aortic Valve Replacement: A Systematic Review

  • Spencer C. Lacy;Mina M. Benjamin;Mohammed Osman;Mushabbar A. Syed;Menhel Kinno
    • Journal of Cardiovascular Imaging
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    • v.31 no.2
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    • pp.108-115
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    • 2023
  • BACKGROUND: Minimizing contrast dose and radiation exposure while maintaining image quality during computed tomography angiography (CTA) for transcatheter aortic valve replacement (TAVR) is desirable, but not well established. This systematic review compares image quality for low contrast and low kV CTA versus conventional CTA in patients with aortic stenosis undergoing TAVR planning. METHODS: We performed a systematic literature review to identify clinical studies comparing imaging strategies for patients with aortic stenosis undergoing TAVR planning. The primary outcomes of image quality as assessed by the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were reported as random effects mean difference with 95% confidence interval (CI). RESULTS: We included 6 studies reporting on 353 patients. There was no difference in cardiac SNR (mean difference, -1.42; 95% CI, -5.71 to 2.88; p = 0.52), cardiac CNR (mean difference, -3.83; 95% CI, -9.98 to 2.32; p = 0.22), aortic SNR (mean difference, -0.23; 95% CI, -7.83 to 7.37; p = 0.95), aortic CNR (mean difference, -3.95; 95% CI, -12.03 to 4.13; p = 0.34), and ileofemoral SNR (mean difference, -6.09; 95% CI, -13.80 to 1.62; p = 0.12) between the low dose and conventional protocols. There was a difference in ileofemoral CNR between the low dose and conventional protocols with a mean difference of -9.26 (95% CI, -15.06 to -3.46; p = 0.002). Overall, subjective image quality was similar between the 2 protocols. CONCLUSIONS: This systematic review suggests that low contrast and low kV CTA for TAVR planning provides similar image quality to conventional CTA.

Analysis of the Image Sought by Consumers for Living Atmosphere and Clothing and Home Fashion Preference (수도권 여성의 거주환경 및 의복 추구이미지와 홈패션 디자인 선호도 분석)

  • Kim Chil Soon;Park Su Youn
    • Journal of the Korean Home Economics Association
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    • v.42 no.12 s.202
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    • pp.253-264
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    • 2004
  • The purpose of this study was to conduct research on consumers who seek to portray an image through their living atmosphere and clothing, and to survey the home fashion design preference of Korean women, aged in their 20s to 40s. We distributed questionnaires to 600 women. The reliable questionnaires were used for a statistical analysis. Data analyses were conducted with SPSS program on ANOVA and Pearson correlations. We obtained the following results: 1. Women who are living in larger housing sought 'elegant', 'sophisticated', and 'gorgeous' images. There was a high correlation between the image sought through the surrounding environment and the image sought with clothing. Those who wanted an image of Korean traditional and classic living environment, also sought the same image in their clothing. 2. There was a significant difference in the preference of home fashion products among women seeking specific images in their living environment. In the preference of children's bed sheets and comforters, there was a significant difference in Korean traditional image. In addition, there was a significant difference in the preferred types of curtains in elegant, sophisticated, gorgeous and classic seeking images of environment. These results may be useful for the home fashion stylist or home fashion marketer.

VELOCITY ESTIMATION OF MOVING TARGETS BY AZIMUTH DIFFERENTIALS OF SAR IMAGES;PRELIMINARY RESULTS

  • Park, Jeong-Won;Jung, Hyung-Sup;Won, Joong-Sun
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.625-628
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    • 2007
  • 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 known 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 adopted a method estimating the velocity of moving targets from azimuth differentials of range-compressed image. This method is based on an assumption 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 the constant phase difference is estimated. Finally, range velocity estimates for moving targets are retrieved. This technique is tested using an ENVISAT ASAR image in which several unknown ships are presented. The theoretical accuracy of this technique is discussed by SAR simulation. The advantages and disadvantages of this method over the conventional method are also discussed.

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A Study on the Visual Evaluation and Interpretation about Clothing Form and the Surface Image of Detail (의복형태와 디테일에 의한 표면이미지의 시각적 평가)

  • 이경희;이경희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.18 no.5
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    • pp.646-660
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    • 1994
  • The purpose of this study was to investigate the difference of the visual evaluation about Clothing form and the surface image of detail. This study consists of pre-experiment for selecting the method of expression among detail which shows difference of the image and main experiment for identifying the clothing image as clothing form and the suface image of detial. Main experiment is made of factorial design for three variables-clothing form (H-line, A-line, V-line, X-line), detail (frill, tape), direction (width, length). Questionaire consists of 24 semantic differential scale expressing clothing form and detail. The subjects were 100 female students majoring in clothing and textile.7he data were analyzed by Frequencey, Factor analysis, Anova, scheffe's test and MCA method. The major findings were; 1) The image of clothing form and the surface image of detail were composed of 5 factors; attractiveness, prettiness, attention, modern, young. 2) For the visual evaluation of clothing form as the surface image of detail, there were significant differences in prettiness and attention factors. For the pretty and attentive image, we should express by the image of frill. 3) For the visual evaluation of the image of detail as clothing forms variation, there were significant difference in prettiness by A-line and X-line. 4) For the effect of clothing form and the surface image of detail, main effect was significant in attractiveness, prettiness, attention, modern factor. For the pretty image of clothing, it will be expressed by the image of frill and A-line, X-line. For the attentive image of clothing, it will be expressed by the image of frill and V-line. For the modern image of clothing, it will be expressed by the image of tape and V-line.

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Implementation of Real-time Stereoscopic Image Conversion Algorithm Using Luminance and Vertical Position (휘도와 수직 위치 정보를 이용한 입체 변환 알고리즘 구현)

  • Yun, Jong-Ho;Choi, Myul-Rul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.5
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    • pp.1225-1233
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    • 2008
  • In this paper, the 2D/3D converting algorithm is proposed. The single frame of 2D image is used fur the real-time processing of the proposed algorithm. The proposed algorithm creates a 3D image with the depth map by using the vertical position information of a object in a single frame. In order to real-time processing and improve the hardware complexity, it performs the generation of a depth map using the image sampling, the object segmentation with the luminance standardization and the boundary scan. It might be suitable to a still image and a moving image, and it can provide a good 3D effect on a image such as a long distance image, a landscape, or a panorama photo because it uses a vertical position information. The proposed algorithm can adapt a 3D effect to a image without the restrictions of the direction, velocity or scene change of an object. It has been evaluated with the visual test and the comparing to the MTD(Modified Time Difference) method using the APD(Absolute Parallax Difference).