• Title/Summary/Keyword: Relative Disparity

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Socioeconomic Disparities in Breast Cancer Screening among US Women: Trends from 2000 to 2005

  • Kim, Jae-Young;Jang, Soong-Nang
    • Journal of Preventive Medicine and Public Health
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    • v.41 no.3
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    • pp.186-194
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    • 2008
  • Objectives : This study describes trends in the socioeconomic disparities in breast cancer screening among US women aged 40 or over, from 2000 to 2005. We assessed 1) the disparities in each socioeconomic dimension; 2) the changes in screening mammography rates over time according to income, education, and race; and 3) the sizes and trends of the disparities over time. Methods : Using data from the Behavioral Risk Factor Surveillance System (BRFSS) from 2000 to 2005, we calculated the age-adjusted screening rate according to relative household income, education level, health insurance, and race. Odds ratios and the relative inequality index (RII) were also calculated, controlling for age. Results : Women in their 40s and those with lower relative incomes were less likely to undergo screening mammography. The disparity based on relative income was greater than that based on education or race (the RII among low-income women across the survey years was 3.00 to 3.48). The overall participation rate and absolute differences among socioeconomic groups changed little or decreased slightly across the survey years. However, the degree of each socioeconomic disparity and the relative inequality among socioeconomic positions remained quite consistent. Conclusions : These findings suggest that the trend of the disparity in breast cancer screening varied by socioeconomic dimension. Continued differences in breast cancer screening rates related to income level should be considered in future efforts to decrease the disparities in breast cancer among socioeconomic groups. More focused interventions, as well as the monitoring of trends in cancer screening participation by income and education, are needed in different social settings.

Stereo Vision System Using Relative Stereo Disparity with Subpixel Resolution

  • Kim, Chi-Yen;Ahn, Cheol-Ki;Lee, Min-Cheol
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.407-407
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    • 2000
  • For acquisition of 3-Dimensional information in real space, stereo vision system is suitable. In the stereo system, 3D real world position is derived from translation of coordinates between cameras and world. Thus, to use stereo vision, it is needed to construct a precise system which provides kinematically precise translation between camera and world coordinate, in spite of intricacy and hardness. So much cost and time should be spent to build the system. In this paper, facilely to solve previous problem, a method which can easily obtain 3D informations using reference objects and RSD(Relative Stereo Disparity) is proposed. Instead of direct computation of position with translation of coordinates, only relative stereo disparity in stereo pair of image is used to find the reference depth of objects, and real 3D position is computed with initial condition of reference objects. In computation, subpixel resolution is involved to find the display for accuracy. To find the RSD, corresponding points are calculated in subpixel resolution. So the result in experiemnt will be shown that subpixel resolution is more accurate than 1 pixel resolution.

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A Convergent Approach to Gain a Better Understanding of Alzheimer's Disease: Stereoscopic Vision (융복합적 접근을 통한 알츠하이머형 치매의 이해 증진 : 양안 지각)

  • Kim, Nam-Gyoon;Lee, Ho-Won
    • Journal of the Korea Convergence Society
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    • v.10 no.5
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    • pp.103-110
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    • 2019
  • The present study investigated the effects of AD on stereoscopic vision. Sixty participants (20 AD patients, 20 mild cognitive impairment patients, 20 healthy elderly controls) participated in the study. Two cubes, one on the left and the other on the right of the center of the monitor, appeared at varying distances from the observer with their relative distances controlled in two disparity conditions (absolute vs relative disparity) combined with two disparity directions (crossed vs uncrossed disparity). Participants identified the object that appeared closer to them. Results demonstrated comparable performance with all three groups performing accurately, suggesting that the effect of AD on stereopsis is negligible. Discussion focused on brain pathology affected by AD involving high level visual processing.

Interaction of Binocular Disparity and Pulfrich Effect in the Perception of Rotation Direction and Depth of a Transparent Rotating Cylinder (회전방향과 깊이 지각에서의 양안부등과 Pulfrich 효과의 상호작용)

  • Li Hyung-Chul O.
    • Korean Journal of Cognitive Science
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    • v.16 no.4
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    • pp.243-254
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    • 2005
  • Pulfrich effect implies the possibility that motion information is processed by the system that processes depth information, and this possibility by supported by various neurophysiological studies. Although Pulfrich effect is processed by the system that processes binocular disparity, the representative depth information, there has not been a psychophysical research to determine the characteristics of the interaction between Pulfrich effect and binorular disparity using a stimulus containing the two information sources. Present research examined the characteristics of the interacation between Pulfrich effect and binocular disparity by nenuring the depth and rotation direction of a rotating cylinder comprised of random dots under two different conditions: 1) consistent rendition where the Pulfrich effect and binocular disparity depth the depth and rotation direction of the cylinder in a consistent manner 2) inconsistent rendition where they did not. , The perceived depth of the cylinder in the consistent condition was larger than that in disparity/Pulfrich effect only condition. Interestingly, the perceived rotation direction of the cylinder in the inconsistent condition was modulated by the relative strength of the disparity and the Pulfrich effect. These results imply that binocular disparity and Pulfrich effect are processed by a common neurophysiological methanism.

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A Study on the Regional Patterns of Income and Urban-Rural Disparity in China: Hypothesis Testing of Williamson and Amos (중국의 소득 및 도·농간 지역격차 패턴에 관한 연구 : Williamson과 Amos의 가설검증)

  • Kim, Jong-Sup;Jang, Hun;Zhang, Rui
    • International Area Studies Review
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    • v.17 no.4
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    • pp.67-88
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    • 2013
  • The purpose of this study empirically examines the pattern of regional disparities on the level of development in China's eastern, central, western and northeast regions for the period 1978-2012. To do this, it test Williamson's inverted-U hypothesis and Amos' augmented inverted-U hypothesis, focusing on polarization, polarization reversal, and spatial restructuring. Results of study are as follows: In the absolute economic disparity(AED) models of per capita income within a region, the Williamson's inverted-U hypothesis was supported in the eastern region, central region and inter-region model. The central region and the western region supports Williamson's hypothesis in the case of the relative economic disparity(RED). On the other hand, The inter-region model and the western region supports Amos' augmented inverted-U hypothesis in model of per capita income. In the urban-rural income economic disparity model, the inter-region model of AED and the central region of RED supports Amos' augmented inverted-U hypothesis. But the Williamson's inverted-U hypothesis was supported in the inter-region model and the western region in RED.

Negative Exponential Disparity Based Robust Estimates of Ordered Means in Normal Models

  • Bhattacharya, Bhaskar;Sarkar, Sahadeb;Jeong, Dong-Bin
    • Communications for Statistical Applications and Methods
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    • v.7 no.2
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    • pp.371-383
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    • 2000
  • Lindsay (1994) and Basu et al (1997) show that another density-based distance called the negative exponential disparity (NED) is an excellent competitor to the Hellinger distance (HD) in generating an asymptotically fully efficient and robust estimator. Bhattacharya and Basu (1996) consider estimation of the locations of several normal populations when an order relation between them is known to be true. They empirically show that the robust HD based weighted likelihood estimators compare favorably with the M-estimators based on Huber's $\psi$ function, the Gastworth estimator, and the trimmed mean estimator. In this paper we investigate the performance of the weighted likelihood estimator based on the NED as a robust alternative relative to that based on the HD. The NED based estimator is found to be quite competitive in the settings considered by Bhattacharya and Basu.

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Criterion Suggestion on Relative Disparity, Viewing Distance and Viewing Angle to Minimize 3D Visual Fatigue for Pattern-Retarded Type 3D Display (편광식 3D 디스플레이를 위한 상대적 시차, 시청 거리, 시청 방위에서의 시각피로 최소화 기준 제안)

  • Park, Jong-Jin;Kim, Shinwoo;Li, Hyung-Chul O.
    • Science of Emotion and Sensibility
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    • v.19 no.1
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    • pp.61-70
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    • 2016
  • 3D visual fatigue is known as one of the most important factors that interfere the commercial success of 3D contents. Vergence-accommodation conflict, which is known to occur when an observer watches an image containing binocular disparity presented on a 3D display, has been suggested as a major cause of 3D visual fatigue. This implies that any image incorporating binocular disparity might cause 3D visual fatigue. In order to reduce 3D visual fatigue, it would be necessary to consider indirect ways of reducing 3D visual fatigue as well as eliminating the direct causes of 3D visual fatigue. We have examined the effect of the variables that are expected to affect subjective 3D visual fatigue and these variables included the relative disparity contained in an image, viewing distance and viewing angle. We have also figured out the proper levels of the variables required to minimize 3D visual fatigue. The results indicate that observers began to report significant 3D visual fatigue when the crossed disparity contained in an image exceeded 7.22' and the vertical viewing angle was larger than 15 degree.

The effect of binocular disparity and T-junction on brightness perception in White illusion (양안 시차와 T-교차 정보가White 착시 자극의 밝기 지각에 미치는 영향)

  • Kim, KyungHo;Kim, ShinWoo;Li, Hyung-Chul O.
    • Korean Journal of Cognitive Science
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    • v.28 no.2
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    • pp.91-109
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    • 2017
  • The purpose of the research was to examine the relative effect of binocular disparity and T-junction on the determination of object's belongingness in brightness perception when regular repeating structure was present in the stimuli. Using Howe's stimuli, the variation of White illusion stimuli, Experiment 1 found that object's belongingness was mainly determined by monocular information (T-junction as well as regular repeating structure) rather than by binocular disparity when both informations on belongingness were inconsistent. Experiment 2, using the stimuli employing only regular repeating structure and binocular disparity, found that object's belongingness was not determined by any single information. These results imply that when the regular repeating structure and binocular disparity are inconsistent on object's belongingness, T-junction plays an important role in the determination of the object's belongingness and that the brightness perception is affected by it.

SLAM Method by Disparity Change and Partial Segmentation of Scene Structure (시차변화(Disparity Change)와 장면의 부분 분할을 이용한 SLAM 방법)

  • Choi, Jaewoo;Lee, Chulhee;Eem, Changkyoung;Hong, Hyunki
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.8
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    • pp.132-139
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    • 2015
  • Visual SLAM(Simultaneous Localization And Mapping) has been used widely to estimate a mobile robot's location. Visual SLAM estimates relative motions with static visual features over image sequence. Because visual SLAM methods assume generally static features in the environment, we cannot obtain precise results in dynamic situation including many moving objects: cars and human beings. This paper presents a stereo vision based SLAM method in dynamic environment. First, we extract disparity map with stereo vision and compute optical flow. We then compute disparity change that is the estimated flow field between stereo views. After examining the disparity change value, we detect ROIs(Region Of Interest) in disparity space to determine dynamic scene objects. In indoor environment, many structural planes like walls may be determined as false dynamic elements. To solve this problem, we segment the scene into planar structure. More specifically, disparity values by the stereo vision are projected to X-Z plane and we employ Hough transform to determine planes. In final step, we remove ROIs nearby the walls and discriminate static scene elements in indoor environment. The experimental results show that the proposed method can obtain stable performance in dynamic environment.

Disparity of Human Capital across Regions: the Impact of Aging (인적자본의 지역간 불평등: 고령화의 영향)

  • Kim, Woo-Yung
    • Journal of the Korean Geographical Society
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    • v.49 no.5
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    • pp.747-760
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    • 2014
  • This study presents the extent of disparity of human capital across regions, its trend, and the impact of aging on it, using Korean census data of years 1985, 1995, and 2005. Main results are as follows. First, the absolute level of human capital in cities and districts have increased, but the relative positions of those regions have not changed over time. Second, the proportion of college graduated tends to increase as the size of cities increases. Third, following Berry and Glaeser(2005), the increase in the proportion of college graduated is regressed on the initial proportion and the estimates indicate that the disparity of human capital across regions has increased over time. Fourth, the proportion of aging population is shown to have a negative relationship with the proportion of college graduated. Finally, using a counter-factual scenario that there were no differences in proportions of aging population across regions, it is shown that the disparity of human capital across regions could be reduced substantially.

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