• Title/Summary/Keyword: Mean Distance

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MEAN DISTANCE OF BROWNIAN MOTION ON A RIEMANNIAN MANIFOLD

  • Kim, Yoon-Tae;Park, Hyun-Suk
    • Proceedings of the Korean Statistical Society Conference
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    • 2002.05a
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    • pp.45-48
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    • 2002
  • Consider the mean distance of Brownian motion on Riemannian manifolds. We obtain the first three terms of the asymptotic expansion of the mean distance by means of Stochastic Differential Equation(SDE) for Brownian motion on Riemannian manifold. This method proves to be much simpler for further expansion than the methods developed by Liao and Zheng(1995). Our expansion gives the same characterizations as the mean exit time from a small geodesic ball with regard to Euclidean space and the rank 1 symmetric spaces.

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A STUDY ON THE MEASUREMENT OF MAXIMUM INTERINCISAL DISTANCE IN KOREAN ADULTS (한국인(韓國人) 청장년(靑壮年)에 있어서 최대개구(最大開口)에 따른 전치절단간(前齒切端間)의 거이계측(距離計測)에 관(關)한 연구(硏究))

  • Cho, Won-Haing
    • The Journal of Korean Academy of Prosthodontics
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    • v.11 no.1
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    • pp.9-14
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    • 1971
  • The author measured the maximum interincisal distance by means of the sliding caliper. The subjects measured here were 149 healthy Korean males and 229 females, ranging from 15 to 49 years old, with normal occlusion. The results were as follows; 1. The mean value of maximum interincisal distance was $50.03{\pm}0.22mm$. in male and $45.18{\pm}0.14mm$. in female. 2. There was a significant difference in the mean value between male female. 3. The interincisal distances in maximum opening were slightly larger in male than female. 4. There was no significant difference in the mean value between the age groups in Korean adults. But it has been revealed that there was apparent difference in the mean value between 15~19 years and 20~29 years old, in female. 5. It has been appeared that maximum interincisal distance in male was 69mm, minimum 37mm., and maximum interincisal distance in female was 58mm. minimum. 30mm.

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Anatomic Study of Pterygomaxillary Junctions in Koreans

  • Kim, Dong-Yul;Cho, Yeong-Cheol;Sung, Iel-Yong;Yun, Dae-Kawn;Kim, Min-Uk;Kim, Ji-Uk;Son, Hyung-Suck;Son, Jang-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.35 no.6
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    • pp.368-375
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    • 2013
  • Purpose: This study is to evaluate the location of descending palatine artery, the anatomy of pterygomaxillary junction, and the association between the obtained anatomic values and several variables. Methods: We studied 40 patients who were treated for dentofacial deformites from January 2010 to December 2012 in Ulsan University Hospital, Ulsan, Korea. Cone beam computed tomogram (CBCT) was done for all patients. The reference point was approximately 5 to 7 mm above anterior nasal spine on axial image. We evaluated the location of the greater palatine canal (line a: on the coronal view, the shortest line between the center of greater palatine canal and pterygoid fossa; distance a: the distance of line a). We also measured the thickness (line b: on the coronal view, the shortest line between maxillary posterior sinus wall and pterygoid fossa; distance b: distance of line b), width (line c: on the coronal view, the line perpendicular to the line b and the nearest line from the most concave point of lateral pterygoid plate to the medial pterygoid plate; distance c: distance of line c) and height (line d: on sagittal view, the vertically longest line of pterygoid junction; distance d: the distance of line d) in pterygomaxillary junctions. We evaluated the association between the obtained anatomic values and several variables (sex, age, height and weight). Results: The mean distance a was 4.78 mm, mean distance b was 5.53 mm, mean distance c was 8.01 mm and mean distance d was 13.22 mm. The differences between age and mean distance c and weight and mean distance d in pterygomaxillary junctions are statistically significant. Conclusion: There apparently is anatomic variation of pterygomaxillary junctions by various values, particularly weight and age in a Korean clinical population.

The study of reading pupillary distance of the aged population of rural community (농촌지역 노인들의 근용 안경의 동공간거리에 관한 연구)

  • Lee, Il Hoon
    • Journal of Korean Ophthalmic Optics Society
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    • v.5 no.2
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    • pp.43-47
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    • 2000
  • The purpose of this study is evaluate for effect quality eye care to the aged population of rural community. This study investigated one of important factors in dispensing distance pupillary distance. measured reading pupillary distance, calculated reading pupillary distance into age group and sex. I measured pupillary distance and near inter pupillary distance with corneal reflection pupillometer(shin Nippon PD-82) The objects are male and female living rural community at least 60 years old. The mean pupillary distance for distance of male and female were 63.52 mm, 61.24 mm, respectively. The mean measured reading pupillary distance of male and female were 60.12 mm, 58.08 mm, respectively. Gradient and difference between male and female were same with mean pupillary distance for distance. The result of comparison the mean difference of the mean measured reading pupillary distance and the calculated reading pupillary distance into the age group and sex. This result of changes of addition, as the age is older, the mean addition is greater than youth. I'd like to compare changes of these factors influenced by environmental factors, however I couldn't see about these. So I couldn't considered their relationship and some possible problems of wearing commercial reading glass.

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Analysis of Harmonic Mean Distance Calculation in Global Illumination Algorithms (전역 조명 알고리즘에서의 조화 평균 거리 계산의 분석)

  • Cha, Deuk-Hyun;Ihm, In-Sung
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.2
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    • pp.186-200
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    • 2010
  • In order to render global illumination realistically, we need to accurately compute the direct and indirect illumination that represents the light information incoming through complex light paths. In this process, the indirect illumination at given point is greatly affected by surrounding geometries. Harmonic mean distance is a mathematical tool which is often used as a metric indicating the distance from a surface point to its visible objects in 3D space, and plays a key role in such advanced global illumination algorithms as irradiance/radiance caching and ambient occlusion. In this paper, we analyze the accuracy of harmonic mean distance estimated against various environments in the final gathering and photon mapping methods. Based on the experimental results, we discuss our experiences and future directions that may help develop an effective harmonic mean distance computation method in the future.

THE EXPANSION OF MEAN DISTANCE OF BROWNIAN MOTION ON RIEMANNIAN MANIFOLD

  • Kim, Yoon-Tae;Park, Hyun-Suk;Jeon, Jong-Woo
    • Proceedings of the Korean Statistical Society Conference
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    • 2003.05a
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    • pp.37-42
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    • 2003
  • We study the asymptotic expansion in small time of the mean distance of Brownian motion on Riemannian manifolds. We compute the first four terms of the asymptotic expansion of the mean distance by using the decomposition of Laplacian into homogeneous components. This expansion can he expressed in terms of the scalar valued curvature invariants of order 2, 4, 6.

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Distance Transform Using Upper Mean (Upper Mean을 이용한 Distance Transform)

  • Park Joungwook;Park Jeungchul;Lee Kwan H.
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.11a
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    • pp.718-720
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    • 2005
  • 반짝이는 물체를 촬영하면 이미지에 하이라이트(highlight)와 반짝거림(specularity)이 발생한다. 하이라이트가 발생한 이미지에서 하이라이트를 제거하고 원색으로 복원하는 방법 중에 하나가 하이라이트 색 복원(inpainting)이다. 하이라이트 색을 복원하는 과정은 다음 두 단계로 구성된다. 첫 단계로 하이라이트의 위치를 알고 있다고 가정하aus 하이라이트의 주변 영역을 찾고 CL-projection을 이용해 주변 영역의 색에서 하이라이트나 반짝거림의 영향을 제거한다. 두 번째 단계로 하이라이트 주변 영역의 색을 기반으로 upper mean을 이용하여 distance transform을 수행한다. Upper mean을 이용한 distance transform의 가장 큰 장점은 하이라이트 주변을 보정하고 그 정보를 이용하기 때문에 하이라이트 색을 복원할 뿐만 아니라 반짝거림에 대한 보정도 된다.

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Factors Affecting Tibial Tuberosity-Trochlear Groove Distance in Recurrent Patellar Dislocation

  • Prakash, Jatin;Seon, Jong-Keun;Ahn, Hyeon-Woon;Cho, Kyu-Jin;Im, Chae-Jin;Song, Eun Kyoo
    • Clinics in Orthopedic Surgery
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    • v.10 no.4
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    • pp.420-426
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    • 2018
  • Background: The tibial tuberosity-trochlear groove (TT-TG) distance is used to determine the necessity of tibial tubercle osteotomy. We conducted this study to determine the extent to which each of the tibial tuberosity lateralization, trochlear groove medialization, and knee rotation angle affects the TT-TG distance in both normal and patella dislocated patients and thereby scrutinize the rationale for tuberosity transfer based on the TT-TG distance. Methods: Retrospective analysis of rotational profile computed tomography was done for patella dislocated and control group patients. Femoral anteversion, tibial torsion, knee rotation angle, tuberosity lateralization, and trochlear groove medialization were assessed in all patients. Relationship of these parameters with the TT-TG distance was investigated to evaluate their effects on the TT-TG distance. Results: We observed that the patellar dislocation group, compared to the control group, had increased TT-TG distance (mean, 19.05 mm vs. 9.02 mm) and greater tuberosity lateralization (mean, 64.1% vs. 60.7%) and tibial external rotation in relation to the femur (mean, $7.9^{\circ}$ vs. $-0.81^{\circ}$). Conclusions: Tuberosity lateralization and knee rotation were factors affecting patellar dislocation. These factors should be considered in addition to the TT-TG distance to determine the need for tibial tubercle osteotomy in patients with patellar dislocation.

A Study on the Position and Length of the Maxillary Central Incisor in Koreans (한국인의 상악중절치 위치 및 길이에 관한 연구)

  • Shin, Sang-Wan;Heo, Yun-Seok
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.5 no.1
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    • pp.1-12
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    • 1996
  • The arrangement of anterior artificial teeth is an important factor on the esthetics in the construction of complete dentures and prostheses. During construction of the complete denture the position of maxillary central incisor plays an important role in the arrangements of artificial teeth. The proper position of maxillary central incisor provides natural appearance of anterior teeth and the anterior reference point of occlusal plane. Many methods have been utilized to eatablish the position of the maxillary central incisor in complete denture prosthodontics. However, there has not been provided for the reference for Korean yet. This study was aimed to extablish a guide for the position of the maxillary central inciosr in Koreans. The horizontal and vertical distance between the maxillary central incisor and incisive papilla in Koreans were measured. 1. The mean value of horizontal distance from the maxillary central incisor to the incisive papilla had significant sexual difference, The average distance was 12.648mm in male and 11.385mm in female. 2. The horizontal distance of the incisive papilla had sexual difference, the average distance was 6.182mm in male and 5.622mm in female. 3. The vertical distance from the maxillary central incisor to the incisive papilla had not sexual difference, the average distance was 7.21mm. 4. The crown length of the maxillary central inciosrs from the distal interdental papilla had not sexual difference, the right central incisor was 6.40mm(mean) and the left central inciosr was 6.43mm(mean). 5. The clinical crown length of the maxillary central incisors had not sexual difference, the right central incisor 10.35mm(mean) and the left central incisor was 10.43mm(mean). 6. The shapes of the incisive papilla were pear(68.4%), oval(16%), triangular(6%), irregular(5%), rectangular(4%), and inverted pear(1%) shape.

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A STUDY ON THE POSITIONING OF THE MAXILLARY CENTRAL INCISOR IN KOREANS (한국인의 상악중절치 위치설정에 관한 연구)

  • Heo, Yun-Seok;Shin, Sang-Wan
    • The Journal of Korean Academy of Prosthodontics
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    • v.33 no.1
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    • pp.85-97
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    • 1995
  • The arrangement of anterior artificial teeth is an important factor on the esthetics in the construction of complete denture and prosthesis. During construction of the complete denture the position of maxillary central incisor plays an important role in the arrangements of artificial teeth. The proper position of maxillary central incisor provides natural appearance of anterior teeth and the anterior reference point of occlusal plane. Many methods have been utilized to eatablish the position of the maxillary central incisor in complete denture prosthodontics. However, there has not been provided for the reference for Korean yet. This study was aimed to extablish the position of the maxillary central inciosr in Korean. The horizontal and vertical distance between the maxillary central incisor and incisive papilla in korean were measured. The results were as follows : 1. The mean value of horizontal distance from the maxillary central incisor to the incisive papilla had significant sexual difference, the average distance was 12.648mm (male), 11.385mm(female). 2. The horizontal distance of incisive papilla had sexual difference, the average distance was 6.182mm(male), 5.622mm(female). 3. The vertical distance from the maxillary central incisor to the incisive papilla had not sexual difference, the average distance was 7.21mm. 4. The crown length of maxillary central inciosrs from the distal interdental papilla had not sexual difference, the right central incisor was 6.40mm(mean) and the left central inciosr was 6.43mm(mean). 5. The clinical crown length of the maxillary central incisors had not sexual difference, the right central incisor 10.35mm(mean) and the left central incisor was 10.43mm(mean). 6. The anatomic shapes of incisive papilla were pear(68.4%), oval(16%), triangular(6%), irregular(5%), rectangular(4%), and inverted pear(1%) shape.

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