• 제목/요약/키워드: Mean Distance

검색결과 1,693건 처리시간 0.034초

MEAN DISTANCE OF BROWNIAN MOTION ON A RIEMANNIAN MANIFOLD

  • 김윤태;박현숙
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2002년도 춘계 학술발표회 논문집
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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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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) (A STUDY ON THE MEASUREMENT OF MAXIMUM INTERINCISAL DISTANCE IN KOREAN ADULTS)

  • 조원행
    • 대한치과보철학회지
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    • 제11권1호
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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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    • 제35권6호
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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.

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

  • 이일훈
    • 한국안광학회지
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    • 제5권2호
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    • pp.43-47
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    • 2000
  • 본 연구에서는 농촌지역에 거주하는 노령인구의 원용동공간 거리와 근용 동공간거리, 원용동공간거리로부터 계산한 근용동공간 거리, 가입도와의 상관관계를 알아보았으며 상용화된 노안경에 관한 보고를 본 연구의 결과와 비교하여 이때 발생할 수 있는 문제점을 알아보고자 한다. 전라북도 김제시에 거주하고 있는 60세 이상 남자 88명, 여자 169명, 계 292명을 대상으로 선정된 대상자들의 분포는 남자 64~81, 여자는 61~81세 사이였다. 1. 남자와 여자의 원용 동공간거리는 각각 63.52 mm, 61.24 mm이었고 나이가 듦에 따라 점차 작아짐을 보였다. 2. 근용 동공간거리는 남자와 여자가 각각 60.12 mm, 58.08 mm이었고 남녀간의 차이와 변화 추세는 원용동공간거리의 변화와 유사한 경향을 보였다. 3. 측정된 근용 동공간거리와 원용동공간 거리로부터 계산된 근용 동공간 거리를 성별로 비교한 결과 남, 여 각각 1.68 mm, 2.19 mm로 여자가 남자보다 더 큰 차이를 보였다. 4. 가입도는 나이가 듦에 따라 점차 커지고 있었으며 남녀간의 차이는 60대에서 2.64 Dptr. 정도의 큰 차이를 보이다가 80대에 들어서는 불과 0.07 Dptr.의 미세한 차이를 보였다. 농촌 지역에 거주하고 있는 대상자를 선정함으로써 환경적 요인을 비교하고자 했으나 비교할만한 선행연구를 볼 수 없었다.

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

  • 차득현;임인성
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제16권2호
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    • pp.186-200
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    • 2010
  • 전역 조명(global illumination) 효과를 사실적으로 렌더링하기 위해서는 복잡한 경로를 통해 입사하는 빛의 정보 해당하는 직접 조명 및 간접 조명을 정확하게 계산해주어야 한다. 이 과정에서 주어진 물체 표면 지점에 대해 계산되는 간접 조명 정보는 주변 환경의 기하적인 형태에 큰 영향을 받게 된다. 조화 평균 거리(harmonic mean distance)는 3차원 공간상에서 주어진 한 지점에서 보이는 물체들과의 거리를 나타내는 척도로 많이 사용되는 수학적 도구로서, 광휘 캐시(irradiance/radiance cache)나 환경 폐색(ambient occlusion) 등의 렌더링 효과를 생성하는데 주요하게 사용된다. 본 논문에서는 대표적인 고품질 전역 조명 렌더링 알고리즘인 최종 수집(final gathering) 방법 및 포톤 매핑(photon mapping) 기법을 통해 다양한 환경에서 계산되는 조화 평균 거리에 대한 근사값의 정확성에 대해 분석한다. 이러한 분석 결과를 기반으로 효과적인 조화 평균 거리 계산의 근사화 기법 개발에 있어서 고려해야 할 점들과 방향을 제시한다.

THE EXPANSION OF MEAN DISTANCE OF BROWNIAN MOTION ON RIEMANNIAN MANIFOLD

  • Kim, Yoon-Tae;Park, Hyun-Suk;Jeon, Jong-Woo
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2003년도 춘계 학술발표회 논문집
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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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Upper Mean을 이용한 Distance Transform (Distance Transform Using Upper Mean)

  • 박정욱;박정철;이관행
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2005년도 가을 학술발표논문집 Vol.32 No.2 (1)
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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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    • 제10권4호
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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.

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

  • 신상완;허윤석
    • 대한심미치과학회지
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    • 제5권1호
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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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한국인의 상악중절치 위치설정에 관한 연구 (A STUDY ON THE POSITIONING OF THE MAXILLARY CENTRAL INCISOR IN KOREANS)

  • 허윤석;신상완
    • 대한치과보철학회지
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    • 제33권1호
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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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