• Title/Summary/Keyword: Triangle Distribution Function

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p-Adaptive Mesh Refinement of Plate Bending Problem by Modified SPR Technique (수정 SPR 기법에 의한 휨을 받는 평판문제의 적응적 p-체눈 세분화)

  • Jo, Jun-Hyung;Lee, Hee-Jung;Woo, Kwang-Sung
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.481-486
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    • 2007
  • The Zienkiewicz-Zhu(Z/Z) error estimate is slightly modified for the hierarchical p-refinement, and is then applied to L-shaped plates subjected to bending to demonstrate its effectiveness. An adaptive procedure in finite element analysis is presented by p-refinement of meshes in conjunction with a posteriori error estimator that is based on the superconvergent patch recovery(SPR) technique. The modified Z/Z error estimate p-refinement is different from the conventional approach because the high order shape functions based on integrals of Legendre polynomials are used to interpolate displacements within an element, on the other hand, the same order of basis function based on Pascal's triangle tree is also used to interpolate recovered stresses. The least-square method is used to fit a polynomial to the stresses computed at the sampling points. The strategy of finding a nearly optimal distribution of polynomial degrees on a fixed finite element mesh is discussed such that a particular element has to be refined automatically to obtain an acceptable level of accuracy by increasing p-levels non-uniformly or selectively. It is noted that the error decreases rapidly with an increase in the number of degrees of freedom and the sequences of p-distributions obtained by the proposed error indicator closely follow the optimal trajectory.

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PBR(Physically based Render) simulation considered mathematical Fresnel model for Game Improvement (효율적 게임개선을 위한 프레넬수학모델의 PBR 시뮬레이션)

  • Kim, Seongdong
    • Journal of Korea Game Society
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    • v.16 no.1
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    • pp.111-118
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    • 2016
  • This paper proposes the mathematical model of Fresnel effect used to illuminate and simulate a surface character model for defense game play. The term illumination is used to represent the process by which the amount of light reaching a surface character model used on game play is determined. The character surface shaders generally use a mathematical model to predict how light will reflect on triangles. The shading normally represents the methods used to determine the color and intensity of light reflected toward the viewer for each pixel representing the character surface model of the game. This model computes the reflection and transmission coefficients and compares simulated results to the Fresnel equations for the real game improvement.

Optimal LEACH Protocol with Improved Bat Algorithm in Wireless Sensor Networks

  • Cai, Xingjuan;Sun, Youqiang;Cui, Zhihua;Zhang, Wensheng;Chen, Jinjun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.5
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    • pp.2469-2490
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    • 2019
  • A low-energy adaptive clustering hierarchy (LEACH) protocol is a low-power adaptive cluster routing protocol which was proposed by MIT's Chandrakasan for sensor networks. In the LEACH protocol, the selection mode of cluster-head nodes is a random selection of cycles, which may result in uneven distribution of nodal energy and reduce the lifetime of the entire network. Hence, we propose a new selection method to enhance the lifetime of network, in this selection function, the energy consumed between nodes in the clusters and the power consumed by the transfer between the cluster head and the base station are considered at the same time. Meanwhile, the improved FTBA algorithm integrating the curve strategy is proposed to enhance local and global search capabilities. Then we combine the improved BA with LEACH, and use the intelligent algorithm to select the cluster head. Experiment results show that the improved BA has stronger optimization ability than other optimization algorithms, which the method we proposed (FTBA-TC-LEACH) is superior than the LEACH and LEACH with standard BA (SBA-LEACH). The FTBA-TC-LEACH can obviously reduce network energy consumption and enhance the lifetime of wireless sensor networks (WSNs).

Clinical Features of Retinal Correspondence according to Refractive Errors and Deviation Angles (굴절이상과 편위각에 따른 망막대응의 임상적 고찰)

  • Wi, Dae-Gwang;Joo, Seok-Hee;Lee, Koon-Ja;Leem, Hyun-Sung
    • Journal of Korean Ophthalmic Optics Society
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    • v.15 no.4
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    • pp.367-372
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    • 2010
  • Purpose: The purpose of this study was to provide useful information for evaluating the sensory function of patients with strabismus by identifying the distribution of anomalous retinal correspondence (ARC) and normal retinal correspondence (NRC) by the degree of refractive errors and deviation angles. Methods: Objective refraction (AR/K, Cannon RK-F1, Japan) and subjective refraction tests were performed on 56 subjects (male: 26, female: 30) by an examiner; objective deviation angle was measured using synoptophore (OCULUS Synoptophore, Germany) with subject' eyes fully corrected for distance, and then subjective deviation angle was measured. Results: In all groups with refractive errors, the number of ARC was larger than that of NRC(67%). Particularly, it was largest in groups with myopia (71%), and in all groups, the number of UARC was larger than that of HARC. In groups with anisometropia, although the numbers of NRC and ARC were same, the number of UARC was larger than that of HARC as in other groups. In the distribution of NRC and ARC by deviation angle, the number of NRC was larger than that of ARC (46%) only at microstrabismus (0 ~ ${\pm}10{\triangle}$). Conclusions: Normal retinal correspondence were the most emmetropia in the retinal response were much higher than in the more hyperopia than the retinal correspondence were more myopia. In addition, the smaller the angle of retinal correspondence Normal over many, but overall, respectively.

Modified Fisher method for unilateral cleft lip-report of cases

  • Kim, Hui Young;Park, Joonhyoung;Chang, Ming-Chih;Song, In Seok;Seo, Byoung Moo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.39
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    • pp.12.1-12.5
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    • 2017
  • Background: Rehabilitation of normal function and form is essential in cleft lip repair. In 2005, Dr. David M. Fisher introduced an innovative method, named "an anatomical subunit approximation technique" in unilateral cleft lip repair. According to this method, circumferential incision along the columella on cleft side of the medial flap is continued to the planned top of the Cupid's bow in straight manner, which runs parallel to the unaffected philtral ridge. Usually, small inlet incision is needed to lengthen the medial flap. On lateral flap, small triangle just above the cutaneous roll is used to prevent unesthetic shortening of upper lip. This allows better continuity of the Cupid's bow and ideal distribution of tension. Case presentation: As a modification to original method, orbicularis oris muscle overlapping suture is applied to make the elevated philtral ridge. Concomitant primary rhinoplasty also results in good esthetic outcome with symmetric nostrils and correction of alar web. As satisfactory results were obtained in three incomplete and one complete unilateral cleft lip patients, indicating Fisher's method can be useful in cleft lip surgery with functional and esthetic outcome. Conclusions: Clinically applied Fisher's method in unilateral cleft lip patients proved the effectiveness in improving the esthetic results with good symmetry. This method also applied with primary rhinoplasty.

The Selective p-Distribution for Adaptive Refinement of L-Shaped Plates Subiected to Bending (휨을 받는 L-형 평판의 적응적 세분화를 위한 선택적 p-분배)

  • Woo, Kwang-Sung;Jo, Jun-Hyung;Lee, Seung-Joon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.20 no.5
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    • pp.533-541
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    • 2007
  • The Zienkiewicz-Zhu(Z/Z) error estimate is slightly modified for the hierarchical p-refinement, and is then applied to L-shaped plates subjected to bending to demonstrate its effectiveness. An adaptive procedure in finite element analysis is presented by p-refinement of meshes in conjunction with a posteriori error estimator that is based on the superconvergent patch recovery(SPR) technique. The modified Z/Z error estimate p-refinement is different from the conventional approach because the high order shape functions based on integrals of Legendre polynomials are used to interpolate displacements within an element, on the other hand, the same order of basis function based on Pascal's triangle tree is also used to interpolate recovered stresses. The least-square method is used to fit a polynomial to the stresses computed at the sampling points. The strategy of finding a nearly optimal distribution of polynomial degrees on a fixed finite element mesh is discussed such that a particular element has to be refined automatically to obtain an acceptable level of accuracy by increasing p-levels non-uniformly or selectively. It is noted that the error decreases rapidly with an increase in the number of degrees of freedom and the sequences of p-distributions obtained by the proposed error indicator closely follow the optimal trajectory.

Analysis of the Correlation between atrophy of exocervical epithelial cell and osteoporosis (자궁경부 상피세포위축과 골다공증의 상관관계 분석)

  • Lee, Dae-Il;Nam, Ha-Gyeong;Lee, Mi-Hwa;Gwak, Min-Jeong;Lee, Hyeon-Jeong;Lee, Su-Bae;Hong, Gwang-Seon
    • Journal of Korea Association of Health Promotion
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    • v.4 no.1
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    • pp.75-84
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    • 2006
  • Background : Osteoporosis and atrophic cell pattern in Pap smear are frequent findings In postmenopausal women due to loss of ovarian function, The present study attempted to find out possible correlation between morphologic characteristics of Pap smear and osteoporosis. Material & methods: The subjects were 825 women(age from 35 to 80) who had undergone Pap smear and bone mineral density(BMD) at The Korea Association of Health Promotion, Seoul Branch, from March 8 to May 10, 2005. Pap smears from 825 women were reviewed and classified either mature cell pattern or atrophic cell pattern by their cytologic patterns, BMD were measured using LUNAR DPX MdIQ(Minster, Ohio, USA). BMD value of lumbar spine(Ll, L2,L3 and L4) were measured from 825 women and BMD value of proximal region off emur(neck NK, Wards triangle WT, and trochanter TR) were measured from 818 women and their bone status were classified as normal( T-sore:>-1.0), osteopenia (T-score: -l~<-2,5) and osteoporosis(T-score: ≤ -2.5). And age distribution of Pap smear, average T-value andfrequency ofsteoporo-sis of each region of the bone, percentage of osteoporosis of each boneregion by age group and changing pattern of percentage of osteopenia and osteoporosis in certain postmenopausal period were compared between mature and atrophic cell pattern. Results: Pap smears revealed total mature cell pattern 53,9%(445/825) and total atrophic cell pattern 46.1%(380/825), Percentage of mature cell pattern decreased from 98.2%(168/171)under 44 age group to 13,3%(17/128) over 65 age group and mature cell pattern increased from 1.8%(3/171) under 44 age group to 86.7%(111/128) oyer 65 age group. Mean T-value of each region of lumbar spine and femur of mature cell pattern were lower than that of atrophic cell pattern about -1,5. And osteoporosis has noted in atrophic cell pattern showing odds ratio Ll 13.9, L2 15.3, L3 12.0, L4 10,4, UK 6.7, WT 10.9 and TR 4.1.Atrophic cell pattern started to increase after 45 years of age and osteoporosis of a trophic cell pattern started after 55 years of age. During 50 to 64 years of age period, L3, L4 and WT revealed parallel increased of osteopenia and osteoporosis and Ll, L2 revealed decreased of osteopenia and increased of osteoporosis. nia Conclusion: Above findings suggest that atrophic cell pattern of Pap smear precedes osteoporosis about 10 years and one of predictor of osteoporosis.

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