• 제목/요약/키워드: Image Correlation

검색결과 2,519건 처리시간 0.028초

영역 분류 및 대역간 상관성을 이용한 원격 센싱된 인공위성 화상데이타의 부호화 (Coding of remotely sensed satellite image data using region classification and interband correlation)

  • 김영춘;이건일
    • 한국통신학회논문지
    • /
    • 제22권8호
    • /
    • pp.1722-1732
    • /
    • 1997
  • In this paper, we propose a coding method of remotely sensed satellite image data using region classification and interband correlation. This method classifies each pixel vector consider spectral characteristics. Then we perform the classified intraband VQ to remove spatial (intraband redundancy for a reference band image. To remove interband redundancy effectively, we perform the classified interband prediction for the band images that the high correlation spectrally and perform the classified interband VQ for the remaining band images. Experiments on LANDSAT TM image show that the coding efficiency of the proposed method is better than that of the conventional Gupta's method. Especially, this method removes redundancies effectively for satellite iamge including various geographical objects and for and images that have low interband correlation.

  • PDF

Assessment of speckle image through particle size and image sharpness

  • Qian, Boxing;Liang, Jin;Gong, Chunyuan
    • Smart Structures and Systems
    • /
    • 제24권5호
    • /
    • pp.659-668
    • /
    • 2019
  • In digital image correlation, speckle image is closely related to the measurement accuracy. A practical global evaluation criterion for speckle image is presented. Firstly, based on the essential factors of the texture image, both the average particle size and image sharpness are used for the assessment of speckle image. The former is calculated by a simplified auto-covariance function and Gaussian fitting, and the latter by focusing function. Secondly, the computation of the average particle size and image sharpness is verified by numerical simulation. The influence of these two evaluation parameters on mean deviation and standard deviation is discussed. Then, a physical model from speckle projection to image acquisition is established. The two evaluation parameters can be mapped to the physical devices, which demonstrate that the proposed evaluation method is reasonable. Finally, the engineering application of the evaluation method is pointed out.

체질량지수에 따른 일부 대학생의 체형인식도와 식행동에 관한 연구 (Body Image Recognition and Dietary Behaviors of College Students According to the Body Mass Index)

  • 김시연;이홍미;송경희
    • 대한지역사회영양학회지
    • /
    • 제12권1호
    • /
    • pp.3-12
    • /
    • 2007
  • This study was performed to investigate the body image perception by BMI and the dietary behaviors in 803 college students(408 males and 395 females). The degree of obesity was divided into an underweight group with BMI less than $18.5kg/m^2$, a normal group with BMI of $18.5{\sim}22.9kg/m^2$, an overweight group with BMI of $23{\sim}24.9kg/m^2$ and an obese group with BMI over $25.0kg/m^2$. The average ages of subjects were 22.9 years in males and 20.2 years in females. The average weight and height of male subjects were 175.3 cm and 69.6 kg, respectively and those of female subjects were 162.5 cm and 52.0 kg, respectively. The average BMIs of male and female subjects were $22.6kg/m^2$ and $19.7kg/m^2$, respectively. The distribution of subjects who perceived their current body image as ideal body image was 25.7% in males and 10.9% in females, showing that the body image satisfaction of male subjects was 1.5 times higher than that of female subjects. Body image perception for their own bodies was mostly shown as the average or standard shape both in males and females with 64.2% and 54.2%, respectively, but males showed a higher perception rate than females and 31.1% of females and 19.5% of males perceived their bodies as lean shape(p<0.01). The body image satisfaction was 4.20 in males and 3.70 in females, showing more satisfaction in the male subjects(p<0.001). The correlation between body image and physical variables in male subjects indicated that CBI and IBI showed statistically significant correlation and also BMI showed statistically significant correlation with IBI(p<0.001) and CBI(p<0.001). The frequency of eating out increased as the frequency of skipping meals increased(p<0.001) and the frequency of having snacks increased as the frequency of eating out increased(p<0.01). The correlation between body image and physical variables in female subjects showed that CBI and IBI(p<0.001) had statistically significant correlation. Body weight showed statistically significant correlation with CBI(p<0.001), BMI(p<0.001) and height(p<0.001). The frequency of eating out increased as height(p<0.01) and the frequency of skipping meals(p<0.001) increased. When both male and female subjects wanted leaner body shapes, they preferred much leaner shapes despite their current body images belonging in the normal range. Additionally subjects preferred the body image in the normal range in cases when their current body images were lean. In particular, more female subjects had strong desires to become leaner in their body images than male subjects, which could be analyzed as a risk factor for physical him. From the above results, it is considered that both male and female subjects need to establish proper recognition and dietary behaviors for their body images and also need nutritional education and counseling for desirable weight control methods.

DCT와 Correlation을 이용한 자동차번호판 추출에 관한 연구 (A Study For Automobile License Plate Extraction Using DCT and Correlation)

  • 경보현;손태주;남궁연;남궁재찬
    • 한국통신학회논문지
    • /
    • 제25권7A호
    • /
    • pp.1050-1056
    • /
    • 2000
  • 본 논문에서는 디지털 카메라를 통해 얻어진 자동차 영상으로부터 이산코사인변환 (Discrete Cosin Transform : DCT) 과 코렐레이션(Correlation)를 이용한 자동차번호판 영역추출방법을 제안한다. 번호판은 문자와 문자의 배경으로 이루어져 있고 번호판 영역이 직사각현으로 되어있다는 특징을 이용하여 자동차영상을 DCT처리하여 수직, 수평성분만을 추출한 후 이 수직, 수평 성분을 가지는 영상에서 코릴레이션(Correlation)을 이용하여 번호판영역을 추출한다. 추출된 번호판영역은 투영 히스토그램(Histogram)에 의해서 번호판영역내에 있는 문자들을 분리한다. 기존의 방법과 비교하여 날씨가 흐리거나 너무 밝거나 밤에 찍은 영상들에 대해서도 우수한 번호판영상을 추출할 수 있었다.

  • PDF

Study on the Improvement of the Image Analysis Speed in the Digital Image Correlation Measurement System for the 3-Point Bend Test

  • Choi, In Young;Kang, Young June;Hong, Kyung Min;Kim, Seong Jong;Lee, Gil Dong
    • Journal of the Optical Society of Korea
    • /
    • 제18권5호
    • /
    • pp.523-530
    • /
    • 2014
  • Machine material and structural strain are critical factors for appraising mechanical properties and safety. Particularly in three and four-point bending tests, which appraise the deflection and flexural strain of an object due to external force, measurements are made by the crosshead movement or deflection meter of a universal testing machine. The Digital Image Correlation (DIC) method is one of the non-contact measurement methods. It uses the image analyzing method that compares the reference image with the deformed image for measuring the displacement and strain of the objects caused by external force. Accordingly, the advantage of this method is that the object's surface roughness, shape, and temperature have little influence. However, its disadvantage is that it requires extensive time to compare the reference image with the deformed image for measuring the displacement and strain. In this study, an algorithm is developed for DIC that can improve the speed of image analysis for measuring the deflection and strain of an object caused by a three-point bending load. To implement this algorithm for improving the speed of image analysis, LabVIEW 2010 was used. Furthermore, to evaluate the accuracy of the developed fast correlation algorithm, the deflection of an aluminum specimen under a three-point bending load was measured by using the universal test machine and DIC measurement system.

대학캠퍼스 건축물에 대한 이미지평가에 관한 연구 (A Study on the Image Evaluation of Buildings in the University Campus)

  • 김천일;김익환
    • 교육시설 논문지
    • /
    • 제19권3호
    • /
    • pp.13-20
    • /
    • 2012
  • In this study, we performed the psychological analysis on campus facilities for university students with the observation that the evaluation on the physical environment of the campus is related to the image evaluation of the campus users. Specifically, we investigated the cognitive structure and the image evaluation structure of users, i.e., students, on the architectural and morphological elements of campus buildings. The investigation results are summarized as follows. 1) The cognitive structure of students on the architectural and morphological elements was different from building to building. In the case of architectural elements, the campus buildings were rated high, if they were designed with emphasis on symbolic elements, while the campus buildings with simple design were rated low. However, the morphological elements exhibited the opposite results. 2) We extracted six factors by performing the factor analysis for image evaluation. From the analysis results, we found that students showed a different structure of image evaluation for each building. In addition, the image evaluation structures were found to be related with the cognitive structures on architectural and morphological elements. 3) We also performed the correlation analysis between image evaluation structure and cognitive structure on architectural and morphological aspects. The analysis results indicated that each building showed different correlation patterns. In addition, the overall image became better, as they appraised "clarity" and "uniformity" more highly.

유방절제술 환자의 신체상과 삶의 질의 관계 (Body Image and Quality of Life in Women with Mastectomy)

  • 박금자;최재숙
    • 종양간호연구
    • /
    • 제8권2호
    • /
    • pp.86-92
    • /
    • 2008
  • Purpose: This study was designed to investigate the body-image and quality of life in breast cancer patients with mastectomy. Methods: Data were obtained by self-reported questionaries from 110 patients undergone mastectomy from August 1 to 31, 2007. And data were analyzed using SPSS/PC WIN 12.0 program and frequency, percentage, mean, minimum, maximum, t-test, ANOVA, Scheffe test, Pearson's Correlation Coefficient were used. The results of the study were as follows; 1) Mean of Body image of the subjects was $52.54{\pm}6.67$ (range of scale; 17 to 85). Mean of quality of life was $118.01{\pm}34.37$ (range of scale; 0 to 10). 2) There was no significant difference with the score of body image by demographic and disease-related characteristics of subjects. 3) There was significant difference with the score of quality of life by the work type and economic status of subjects. 4) Relationship between body image and quality of life showed moderately strong positive correlation (r=0.408, p<0.0001). Conclusion: Mean of body image and of quality of life in mastectomy patients were moderate. Relationship between body image and quality of life showed moderately strong positive correlation. Therefore, for improving the quality of life, it is needed to improve body image in breast cancer patients with mastectomy.

  • PDF

다차원 명암도 증감 기반 효율적인 영상정합 (An Efficient Image Registration Based on Multidimensional Intensity Fluctuation)

  • 조용현
    • 한국지능시스템학회논문지
    • /
    • 제22권3호
    • /
    • pp.287-293
    • /
    • 2012
  • 본 논문에서는 영상의 다차원 명암도 증감에 기반을 둔 유사도 측정에 의한 효율적인 영상정합 방법을 제안하였다. 여기서 다차원 명암도는 영상의 4방향을 고려한 유사성 판정으로 영상이 가지는 속성을 더욱 더 많이 반영하기 위함이고, 명암도 증감은 인접 픽셀간의 밝기변화를 고려함으로써 좀 더 포괄적으로 유사성을 측정하기 위함이다. 또한 측정된 4방향 각각의 명암도 증감에 대한 정규상호상관계수를 구하고, 그 각각에 바탕을 둔 전체 정규상호상관계수, 각 방향의 상관계수에 대한 산술평균과 단순 곱 및 최대값으로 정규화된 상관계수의 산술평균과 단순 곱으로 정의된 유사도 계수로 각각 정합을 측정하였다. 제안된 방법을 22개의 243*243 픽셀 얼굴영상과 9개의 500*500 픽셀 인물영상을 대상으로 각각 실험한 결과, 영상의 속성을 잘 반영한 우수한 정합성능이 있음을 확인하였다. 특히 각 방향의 상관계수에 대한 산술평균 유사도가 가장 우수한 신뢰성을 가지는 정합척도임을 알 수 있었다.

대학생 SNS 사용시간에 따른 대인관계, 신체상, 학업성취도 (Interpersonal relationship, body image, academic achievement according to SNS use time of college students)

  • 신민정;편하형;김현정;문지현
    • 문화기술의 융합
    • /
    • 제5권1호
    • /
    • pp.257-264
    • /
    • 2019
  • 본 연구는 구조화된 설문지를 활용한 서술적 조사연구로, 대학생 144명에게 SNS 사용시간, 대인관계, 신체상, 학업성취도를 확인하고자 t-test와 ANOVA로 파악하였고, 사후 검정은 Duncan's multiple test로 확인하였다. SNS 사용시간에 따른 대인관계, 신체상, 학업성취도 간의 상관관계는 Pearson's Correlation Coefficients로 파악하였다. 대상자 144명 중 남자는 55명(38.2%), 여자는 89명(61.8%), SNS 사용 시간 여자 2.2시간, 남자1.9시간이었다. SNS 사용 시간과 대인관계 유의한 상관관계 양적 상관을 보였는데(p<.014) 특히 하위요인 중 친밀감과 높은 수준의 양적인 상관관계를 보였으나, 신체상 및 학업성취도 간에는 유의한 상관관계가 나타나지 않았다. 대인관계와 신체상 간의 관계는 강한 양의 상관관계가 나타났다(p<.003).

이미지 상관관계함수를 이용한 디지털 영상의 유사도 비교에 관한 연구 (Study on the Correlation between Digital Images using ICOR)

  • 양형규;최종호
    • 한국컴퓨터정보학회논문지
    • /
    • 제14권3호
    • /
    • pp.75-82
    • /
    • 2009
  • 영상의 비교는 PSNR을 이용하는 것이 일반적이다. PSNR이 35이상일 경우 육안으로 품질 차이를 구분하기 어렵다고 판단한다. 2006년 Lee 등은 원본 이미지 대신 원본 이미지의 MSB 비트열을 공개함으로써 소유권을 증명할 수 있는 프로토콜을 제안하면서, 두 이미지의 MSB 비트열의 유사도를 측정하기 위한 새로운 함수를 사용하였다. 이때의 유사도는 품질을 측정하기 위한 PSNR과는 그 의미가 조금 다른 측면이 있다. 즉, 원본 이미지로부터 생성된 대상 이미지가 현저히 떨어질 경우, PSNR은 매우 낮은 값을 보이지만 품질이 떨어지더라도 유사도 측면에서 본다면 두 영상의 상관관계는 매우 높게 나와야 할 것이다. 본 논문에서는 Lee 등이 제안한 MSB 비교 함수를 수정한 후, ICOR함수를 제안하였으며, 이 함수를 이용하여 두 이미지의 상관관계 판단에 적용할 수 있는지 분석하였다.