• Title/Summary/Keyword: Disparity estimation

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Evaluation of normal masseter muscles on ultrasonography (초음파영상을 이용한 정상 교근의 평가)

  • Hwang, Hyoung-Zoo;Kim, Gyu-Tae;Choi, Yong-Suk;Hwang, Eui-Hwan
    • Imaging Science in Dentistry
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    • v.38 no.2
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    • pp.73-79
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    • 2008
  • Purpose: To assess the internal echo intensity and morphological variability of masseter muscles on ultrasonography and to establish diagnostic criterion of estimation. Materials and Methods: Participants consisted of 50 young adults (male 25, female 25) without pathologic conditions and with full natural dentitions. Sonographic examinations were done with real time ultrasound equipment as Logiq 500 (GE Medical Systems, Seoul, Korea) at 3 parts according to lines paralleling with ala-tragus line as reference line. The thickness and area of masseter muscles according to reference line in cross-sectional images were measured at rest and at maximum contraction. The visibility and width of the internal echogenic intensity of the masseter muscles were also assessed and the muscle appearance was classified into 4 types. Data were statistically analyzed by paired t-test and $x^2$-test. Results: 1. When comparing the thickness and area of masseter muscles concerning with gender, there was few significant difference between right and left sides, however, there were significant differences between males and females except for the greatest thickness of left side. 2. The changes of the greatest thickness and the area between rest and maximum contraction showed that the part of the least thickness manifested more increase at maximum contraction. 3. Each part the manifestations of the internal echogenic intensity of the masseter muscles were different depending on the locations. But there was no statistically significance. Conclusion: Changes of muscles thickness with contraction and internal echogenic intensity with locations showed great disparity within the masseter muscles, which will be diagnostic criteria for pathophysiologic and anatomic changes of masseter muscles.

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Building Extraction and Digital Surface Models Generation from Stereo pairs of Aerial Images (입체 항공사진영상을 이용한 DSM생성 및 건물경계추출)

  • 유환희;김성우;성민규
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.16 no.2
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    • pp.177-185
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    • 1998
  • There is an increasing request for 3D data and outlines on building for urban planning and design. This paper describes an approach to extract building using Digital Surface Models(DSM) and stereo pairs of aerial images. DSM contain informations not only about the topographic surface like Digital Elevation Models(DEM), but also about buildings and other objects higher than the surrounding topographic surface, e.g. tees. We therefore describe our approach consisting of two step procedures. The first step of the approach is to generate DSM by stereo matching using Maximum Likelihood Estimation and Dynamic Programming. The proposed stereo matching is using the cost function for finding the disparity between the left and right image, and the Dynamic Programming for solving the stereo matching problem. The second step is to detect building outlines using the DSM and the edge informations extracted from a digital aerial image by Sobel Operator. The overlay analysis of the DSM and the edge information by Sobel Operator was efficient to detect building outlines.

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The importance of nose, eye, and In-dang(印堂) region in inspecting color diagnosis (망진(望診) 찰색(察色)에 있어서 비(鼻), 안(眼), 인당(印堂)의 중요성)

  • Chang, Jun-Young;Kang, Jung-Soo;Kim, Byoung-Soo
    • Journal of Haehwa Medicine
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    • v.19 no.1
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    • pp.87-98
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    • 2010
  • There are four kinds of diagnosis methods in oriental medicine, and viewing diagnosis(望診) is the most important method among them. There are two ways in viewing diagnosis. These are viewing shape(觀形) and inspecting color(察色). Viewing shape diagnosis includes observation on geometric curve that is made by prominence of bones or lump of flesh, and examination on symmetric disparity and balance of vertical length among three vertical section of face. Inspecting color is literally inspecting several specified region of face. By Viewing shape, we can learn about characteristic physical mechanism of individuals, and basic disposition of reaction from inside and outside infinite stimulations. On the other hand, by inspecting color, we can estimate the very present pathologic and physiologic status of the patient. the estimation is based on principle that inside body changes reveal some reflections on facial skin surface. When you diagnosis patients with inspecting color method, It is important to distinguish color delicately, and to know where to see and what to know from it. The most important and frequently mentioned regions are myong-dang(明堂), eyes(眼) and In-dang(印堂). Myong-dang(明堂) indicates nose. In-dang(印堂) indicates the space between eyebrows. Unlike myong-dang(印堂) and eyes, In-dang(印堂) is occasionally treated as a trivial region then others. But, from research on classical books of facial examination and consideration of it's locational meanings, we've learned In-dang(印堂) is very important in viewing diagnosis, because this region is crossing of the other two regions and this fact means this region expresses the spiritual status as well as physical status in one region.

Estimation of the Amount of Round Wood in Unused Forest Biomass Reporting in Forest Clearing (미이용 산림바이오매스 공급에 있어 수확벌채의 원목 혼입량 추정)

  • Jiyoon, Yang;Jaejung, Lee;Hanseob, Jeong;Sang Hun, Han;Soo Min, Lee
    • New & Renewable Energy
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    • v.18 no.4
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    • pp.70-78
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    • 2022
  • To respond to global warming, there is an increasing interest in eco-friendly alternative energy sources. Therefore, unused forest biomass that has been neglected due to a lack of marketability is attracting attention. With the introduction of the "unused forest biomass certification system" in 2019, ways of determining quantity of unused forest biomass have steadily increased. However, there have been reported cases whereby unused forest biomass weighed more than the amount of harvested trees. It was found that it was possible that forest resources that can be used as round wood were mixed with unused forest biomass. In this context, this study aimed to estimate the amount of mixed round wood in the unused forest biomass supply. The relative expression of growing stock/ha versus the amount of final clearing/ha collected was modeled (y=1.490x-94.341, R2=0.861). As a result, it was found that round wood was mixed into the unused forest biomass, contributing to the disparity observed between the weighted forest biomass and the amount of trees harvested. In conclusion, proper declaration and certification procedures should be carried out for the use of forest resources and promoting unused forest biomass usage.

Urbanization Economies and Urban Scale in China (중국의 도시화경제와 도시규모에 관한 연구)

  • Kim, Sang-wook
    • International Area Studies Review
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    • v.13 no.1
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    • pp.145-166
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    • 2009
  • This paper uses 192 urban data in 1990-2005, and Carlino model, estimate urban agglomeration economies, that is urbanization economies. The results of estimation of urban agglomeration economies suggests that the h value of 145 urban bigger than 1, and h value of 47 urban smaller than 1, that is most of urban has the positive urbanization economies. But the regional disparity is serious, Eastern region's urban agglomeration is obvious, and North-eastern region's urban agglomeration economies is not obvious, appears urban disagglomeration economies. For analyzing the relation between urban agglomeration economies and urban scale, this paper tested the function of urban agglomeration economies. The results suggests that urban agglomeration economies and urban scale has not the inverse U-type function.

Stereoscopic Depth from 3D Contents with Various Disparity (화면 시차로부터 지각되는 3D 컨텐츠의 입체시 깊이)

  • Kham, Keetaek
    • Journal of Broadcast Engineering
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    • v.21 no.1
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    • pp.76-86
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    • 2016
  • This study was investigated whether the perceived depth was changed depending on the measurement methods. In the method of direct comparison, virtual object with one of the various binocular disparities was presented in the frontal space with LEDs which were used for depth estimation for a binocular stimulus, while in the method of indirect comparison, visual object was presented in the frontal space but the LEDs were placed rightward at the angle of 45 degree from the mid-sagittal line. In these experimental setup, the depth of binocular stimulus was directly matched that of LED in direct comparison condition. In indirect comparison condition, however, observer estimated the depth of binocular stimulus, turned one's head rightward to the array of LEDs and turned on the LED which was supposed to be the same depth as binocular stimulus. Additionally, it was investigated whether the perceived depth was different depending on observer's stereo acuity. The results showed that perceived depths measured in the direct comparison were more similar to the depth predicted from geometry than those in the indirect comparison, and that the perceived depths from observers with high stereo acuity were similar to the predicted depth from geometry those from observers with low stereo acuity. These results indicated that stereoscopic depths of the binocular stimuli would vivid and compelling when binocular stimuli was simultaneously presented with real objects in the same visual space, like a mixed reality.

The Analysis of Roll Call Data from the 18th Korean National Assembly: A Bayesian Approach (제 18대 국회 기명투표 분석: 베이즈(Bayesian) 방법론 적용)

  • Hahn, Kyu S.;Kim, Yuneung;Lim, Jongho;Lim, Johan;Kwon, Suhyun;Lee, Kyeong Eun
    • The Korean Journal of Applied Statistics
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    • v.27 no.4
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    • pp.523-541
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    • 2014
  • We apply a Bayesian estimation procedure to the analysis of roll call voting records on 2,389 bills processed during the 18th Korean National Assembly. The analysis of roll calls yields useful tools for to combining the measurement of legislative preference with the models of legislative behavior. The current Bayesian procedure is extremely exible, applicable to any legislative setting, irrespective of the extremism of the legislator's voting history or the number of roll calls available for analysis. It can be applied to any legislative settings, providing a useful solution to many statistical problems inherent in the analysis of roll call voting records. We rst estimate the ideal points of all members of the 18th National Assembly and their condence intervals. Subsequently, using the estimated ideal points, we examine the factional disparity within each major party using the estimated ideal points. Our results clearly suggest that there exists a meaningful ideological spectrum within each party. We also show how the Bayesian procedure can easily be extended to accommodate theoretically interesting theoretical models of legislative behavior. More specically, we demonstrate how the estimated posterior probabilities can be used for identifying pivotal legislators.

3D Reconstruction of an Indoor Scene Using Depth and Color Images (깊이 및 컬러 영상을 이용한 실내환경의 3D 복원)

  • Kim, Se-Hwan;Woo, Woon-Tack
    • Journal of the HCI Society of Korea
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    • v.1 no.1
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    • pp.53-61
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    • 2006
  • In this paper, we propose a novel method for 3D reconstruction of an indoor scene using a multi-view camera. Until now, numerous disparity estimation algorithms have been developed with their own pros and cons. Thus, we may be given various sorts of depth images. In this paper, we deal with the generation of a 3D surface using several 3D point clouds acquired from a generic multi-view camera. Firstly, a 3D point cloud is estimated based on spatio-temporal property of several 3D point clouds. Secondly, the evaluated 3D point clouds, acquired from two viewpoints, are projected onto the same image plane to find correspondences, and registration is conducted through minimizing errors. Finally, a surface is created by fine-tuning 3D coordinates of point clouds, acquired from several viewpoints. The proposed method reduces the computational complexity by searching for corresponding points in 2D image plane, and is carried out effectively even if the precision of 3D point cloud is relatively low by exploiting the correlation with the neighborhood. Furthermore, it is possible to reconstruct an indoor environment by depth and color images on several position by using the multi-view camera. The reconstructed model can be adopted for interaction with as well as navigation in a virtual environment, and Mediated Reality (MR) applications.

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Digital Hologram Compression Technique using Multi-View Prediction based on Image Accumulation (영상집적 기반의 다시점 부호화 기술을 이용한 디지털 홀로그램의 압축 기술)

  • Choi, Hyun-Jun;Seo, Young-Ho;Bae, Jin-Woo;Yoo, Ji-Sang;Kim, Hwa-Sung;Kim, Dong-Wook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.10C
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    • pp.933-941
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    • 2006
  • In this paper, we proposed an efficient coding method for digital hologram (fringe pattern) acquired by a CCD camera or by computer generation using multi-view prediction technique and MPEG video compression standard technique. It proceeds each R, G, or B color component separately. The basic processing unit is a partial image segmented into the size of $N{\times}N$. Each partial image retains the information of the whole object. This method generates an assembled image for a row of the segmented and frequency-transformed partial images, which is the basis of the coding process. That is, a motion estimation and compensation technique of MPEG is applif:d to the reconstructed images from the assembled images with the disparities found during generation of assembled image and the original partial images. Therefore the compressed results are the disparity of eachpartial image to form the assembled image for the corresponding row, assembled image, and the motion vectors and the compensated image for each partial image. The experimental results with the implemented algorithm showed that the proposed method has NC (Normal Correlation) values about 4% higher than the previous method, by which ours has better compression efficiency. Consequently, the Proposed method is expected to be used effectively in the application areas to transmit the digital hologram data. can be identified in comparison with the previous researches and commercial IPs.

Analysis of Research Papers Published by the Korean Journal of Hospice and Palliative Care (The First Issue~2012) (한국 호스피스.완화의료학회지 게재논문 분석(창간호~2012년))

  • Hwang, In Cheol;Kang, Kyung-Ah;Ahn, Hong Yup
    • Journal of Hospice and Palliative Care
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    • v.16 no.2
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    • pp.74-79
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    • 2013
  • The purpose of this paper is to suggest a direction for future studies based on the analysis of the articles published in the Korean Journal of Hospice and Palliative Care from 1998 to 2012. A total of 240 articles (51 reviews, 189 original) were examined in three five-year groups. Categories of analysis include authors' background (profession, region) and general characteristics and qualitative aspects of the original paper (participants, topic, study design, data analysis, ethical consideration, multidisciplinary approach, research funds and sample size estimation). While the journal publishes more of articles than before, it is mainly due to the increase in the number of review articles, not original articles. As for study topics, healthcare industry and physical symptoms were most frequently studied. The disparity in authors' regional background is fading, and more articles are published by nurses than before. Moreover, more studies are funded while fewer papers tend to adopt a multidisciplinary approach or focus on care givers. Also, in terms of a study design, the number of experimental and methodological studies has slightly increased. In the qualitative aspect, studies considered ethical issues and collected participation consent, and fewer studies reported an estimated sample size. In data analysis, post-adjustment comparison decreased, and new analytical methods are increasingly used. Our results indicate the need to conduct research with more extensive scientific data in various fields of hospice and palliative care.