• Title/Summary/Keyword: Inclined Plane

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Covariance patterns between ramus morphology and the rest of the face: A geometric morphometric study

  • Marietta Krusi;Demetrios J. Halazonetis;Theodore Eliades;Vasiliki Koretsi
    • The korean journal of orthodontics
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    • v.53 no.3
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    • pp.185-193
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    • 2023
  • Objective: The growth and development of the mandible strongly depend on modeling changes occurring at its ramus. Here, we investigated covariance patterns between the morphology of the ramus and the rest of the face. Methods: Lateral cephalograms of 159 adults (55 males and 104 females) with no history of orthodontic treatment were collected. Geometric morphometrics with sliding semi-landmarks was used. The covariance between the ramus and face was investigated using a two-block partial least squares analysis (PLS). Sexual dimorphism and allometry were also assessed. Results: Differences in the divergence of the face and anteroposterior relationship of the jaws accounted for 24.1% and 21.6% of shape variation in the sample, respectively. Shape variation was greater in the sagittal plane for males than for females (30.7% vs. 17.4%), whereas variation in the vertical plane was similar for both sexes (23.7% for males and 25.4% for females). Size-related allometric differences between the sexes accounted for the shape variation to a maximum of 6% regarding the face. Regarding the covariation between the shapes of the ramus and the rest of the face, wider and shorter rami were associated with a decreased lower anterior facial height as well as a prognathic mandible and maxilla (PLS 1, 45.5% of the covariance). Additionally, a more posteriorly inclined ramus in the lower region was correlated with a Class II pattern and flat mandibular plane. Conclusions: The width, height, and inclination of the ramus were correlated with facial shape changes in the vertical and sagittal planes.

Waveguide Slot Array Antenna for Heliborne MTD Radar (헬리콥터 탑재 MTD 레이다용 도파관 슬롯배열 안테나)

  • Kim Dong-Seok;Han In-Hee;Gwak Young-Gil;Shin Keun-Sup
    • Proceedings of the IEEK Conference
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    • 2004.06a
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    • pp.139-142
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    • 2004
  • X-band Waveguide slot way antenna is developed for heliborne MTD radar applications. The antenna is composed of multi-layer waveguide structures. Each of them has it's own functions, such as, radiation, power/phase distribution, coupling, etc. Broad-wall offset slots are used for radiators, inclined slots on broad-wall for power distribution to radiating(branch) waveguide, some kind of coaxial probe structures for in-phase coupling and H-plane T-junction power dividers. Antenna is realized by precision machining and careful assembly. It is tested and measured by 3m${\times}$l.7m planar near-field probe, which is set-up in MTG. Far-field calculations have good agreement in tolerable bounds. Special but necessary process such as brazing, will increase the accuracy and performance. Results show promising possibilities of future applications for real systems.

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FLOW PATTERNS PAST TWO NEARBY SPHERES (두 개의 구를 지나는 유동 패턴)

  • Yoon, Dong-Hyeog;Yang, Kyung-Soo
    • Journal of computational fluids engineering
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    • v.13 no.3
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    • pp.14-20
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    • 2008
  • In this investigation, flow patterns past two identical nearby spheres at Re=300 were numerically studied. We considered all possible arrangements of the two spheres in terms of the distance between the spheres and, the angle inclined with respect to the main flow direction. It turns out that significant changes in shedding characteristics are noticed depending on how the two spheres are positioned. Collecting all the numerical results obtained, we propose a diagram for flow pattern on the distance vs. angle plane. The perfect geometrical symmetry implied in the flow configuration allows one to use that diagram to identify flow patterns past two identical spheres arbitrarily positioned in physical space with respect to the main flow direction.

A Numerical Study on the Triboelectrostatic Separation of PVC Materials From Mixed Plastics for Waste Plastic Recycling

  • Ha, Man-Yeong;Jeon, Chung-Hwan;Park, Doo-Seong;Park, Hae-Jin
    • Journal of Mechanical Science and Technology
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    • v.17 no.10
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    • pp.1485-1495
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    • 2003
  • We investigate the triboelectrostatic separation of polyvinylchloride (PVC) from mixed plastics in the laboratory scale triboelectrostatic separation system. The flow and electric fields in the precipitator are obtained from the numerical solution of finite volume method. Using these flow and electric fields, we solved the particle motion equation considering the inertia, drag, gravity and electrostatic forces acted on the particles. The particle trajectories are obtained using a Lagrangian method as a function of different important variables such as Reynolds number, Stokes number, electrostatic force, electric charge and electric field distribution, inclined angle of plane electrodes, particle rebounding, particle charge decay rate after impact on the electrode surface, etc., in order to determine the optimal design conditions. The present predicted results for the cumulative yield represent well the experimental ones.

Ecological Characteristics of Lithospermum erythrorhizon Population in Habitats (지치(Lithospermum erythrorhizon) 개체군 자생지의 생태학적 특성)

  • Ahn, Young-Hee;Jin, Ying-Hua;Choe, Chang-Yong;Lee, Kyung-Mee;Lee, Sang-Hyun
    • Korean Journal of Pharmacognosy
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    • v.40 no.4
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    • pp.289-297
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    • 2009
  • This study was carried out to investigate the ecological characteristic of native Lithospermum erythrorhizon population in Korea. The survey quadrates were located in the middle of native L. erythrorhizon habitats. As the result of the research, the ecological patterns of native habitats were found to be divided into inclined plane type, ridge type, mountain-roadside type, and rock bed type. The research revealed 90 taxa in total, in which 37 families, 63 genera, 23 varieties, 6 forma, 1 sub-species and 60 species were checked in the flora of native L. erythrorhizon habitats.

A Study on Stabilization of Walking and Working Motion of Biped Robot (보행로봇의 워킹 및 작업동작 안정화에 관한 연구)

  • Ha, Eon-Tae;Shim, Hyeon-Seok;Park, In-Man;Lee, Sang-Hyeok;Cha, Bo-Nam;Park, Seong-Jun
    • Journal of the Korean Society of Industry Convergence
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    • v.19 no.1
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    • pp.39-41
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    • 2016
  • In the paper, we propose an stable walking algorithm of biped robot on the ground and working motion stabilization algorithm against external disturbances. We propose obstacle hurdling, incline walking, and going-up stairs algorithm by using infrared sensors and F/T sensors. Also, posture stabilization algorithm against external forces is designed using F/T sensors. Infrared sensors are used to detect the obstacles in he working environment and F/T sensors are used to obtain the ZMP of biped robot. The experimental results show that the biped robot performs obstacle avoidance, obstacle hurdling, walking on the inclined plane by using the proposed walking moton stabilization algorithm.

A HYBRID METHOD FOR HIGHER-ORDER NONLINEAR DIFFUSION EQUATIONS

  • KIM JUNSEOK;SUR JEANMAN
    • Communications of the Korean Mathematical Society
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    • v.20 no.1
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    • pp.179-193
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    • 2005
  • We present results of fully nonlinear time-dependent simulations of a thin liquid film flowing up an inclined plane. Equations of the type $h_t+f_y(h) = -{\in}^3{\nabla}{\cdot}(M(h){\nabla}{\triangle}h)$ arise in the context of thin liquid films driven by a thermal gradient with a counteracting gravitational force, where h = h(x, t) is the fluid film height. A hybrid scheme is constructed for the solution of two-dimensional higher-order nonlinear diffusion equations. Problems in the fluid dynamics of thin films are solved to demonstrate the accuracy and effectiveness of the hybrid scheme.

The Evaluation of Degradation Characteristics of Silicone Rubber for Outdoor by Leakage Current Monitoring (누설전류 모니터링에 의한 옥외용 실리콘 고무의 열화 특성 평가)

  • Kim, Jeong-Ho;Song, Woo-Chang;Cho, Han-Goo;Park, Yong-Kwan
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.2
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    • pp.60-64
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    • 2001
  • The degradation process of silicone rubber was investigated by leakage current monitoring in Inclined-Plane method. DAS (Data Acquisition System) with 12-bit, 8-channel A/D converter was prepared. Average current, cumulative charge, current waveform and the number of peak pulses were measured on-line. And, FFT (Fast Fourier Transform) analysis was performed with stored current waveform. Besides, maximum erosion depth was measured in order to use as the indicator of the degradation process. So, the results of leakage current components and maximum erosion depth measurements were compared to find one or more components which have trends of changing similarly to that of erosion process. The result suggests that the ratio of peak current to r.m.s. current, harmonic contents and the number of peak pulses are well corresponding with the degradation process.

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A Novel Silicon Direct Bonding Technology using Groove Matrix (홈파기를 이용한 새로운 실리콘 직접접합 기술)

  • 김은동;김남균;김상철;박종문;이승환
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.81-84
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    • 1995
  • A reliable bonding between two silicon wafers, regularly grooved and non-grooved, was done by the direct boning technology, It is Presented that high structural duality was realized not only at the bended interface but in the bulk, commensurate with the filling of artificial grooves, which would be attributed to the dislocation-gettering capability of groove free-surfaces during annealing. The groove filling would be explained with mass-transport phenomena assisted by the dislocation movement from initial contact boundaries toward groove surfaces. Intrinsic voids can be easily removed by aid of the grooves. The proposed method yielded also an intimate bonding not only between {111} wafers strongly misoriented and slightly inclined to {111} basal plane but even between {111} and {100} orientation wafers.

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Redistribution of Internal Shear Forces in a Reinforced Concrete Beams (철근콘크리트 보의 전단력 재분배)

  • Rhee, Chang-Shin;Shin, Geun-Ok;Kim, Dae-Joong;Kim, Woo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05a
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    • pp.362-365
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    • 2006
  • This paper presents a model for evaluating the contribution by arch action to shear resistance in shear-critical RC beams. Based on the relationship between shear and bending moment in beams subjected to combined shear and bending, The behavior of a beam is explicitly divided into two base components of the flexural action and the tied arch action. The compatibility condition of the shear deformation that deviates from Bernoulli bending plane is formulated utilizing the smeared truss idealization with an inclined compression chord. From this shear compatibility condition in a beam, the shear contribution by the arch action is numerically decoupled.

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