• 제목/요약/키워드: Geometrical model

검색결과 864건 처리시간 0.029초

스커트 3D 모델의 기하학적 생성 방법 (A Geometrical Generation Method of the Skirt 3D Models)

  • 최우혁;최창석;김효숙;강인애
    • 한국의류학회지
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    • 제27권7호
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    • pp.770-777
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    • 2003
  • This paper proposes a geometrical method for generating and draping the skirt 3D models. The method constructs a 3D basic skirt model using a truncated elliptical cone and generates the various skirt 3D models by controlling the elliptical cone. The B-Spline approximates the 3D drapes which change variously according to the angles and the textiles of the skirts. The mapping sources consist of the textile textures and the skirt 2D model. The 2D models are obtained by mapping the 3D skirt models to the 2D plane. The mapping sources allow us to map the textiles to the 3D skirts. We make the real skirts for the 6 kinds of angles and textiles. and investigate the data of their drape appearances. The investigated data are applied to the virtual skirts. Appearances of the virtual skirts are similar to those of the real.

Elastic rotational restraint of web-post in cellular beams with sinusoidal openings

  • Durif, Sebastien;Bouchair, Abdelhamid;Bacconnet, Claude
    • Steel and Composite Structures
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    • 제18권2호
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    • pp.325-344
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    • 2015
  • Experimental tests on cellular beams with sinusoidal openings showed two main failure modes around the openings. They concern the formation of four plastic hinges and the local instability of the sinusoidal part of the opening. In parallel, numerical analysis of the sinusoidal part of the opening revealed the existence of an elastic rotational restraint between the intermediate web-post and the adjacent opening panel. The aim of the present study is to present an approach to quantify this rotational restraint. Through the response surface method, a mathematical model is proposed. It shows a great ability to predict the rotational restraint value as a function of the geometrical parameters of the opening. This model can be used to perform an extensive study with various geometrical configurations of beams with the aim to develop a reliable and realistic analytical model predicting the resistance of the sinusoidal openings.

A fast gamma-ray dose rate assessment method for complex geometries based on stylized model reconstruction

  • Yang, Li-qun;Liu, Yong-kuo;Peng, Min-jun;Li, Meng-kun;Chao, Nan
    • Nuclear Engineering and Technology
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    • 제51권5호
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    • pp.1436-1443
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    • 2019
  • A fast gamma-ray dose rate assessment method for complex geometries based on stylized model reconstruction and point-kernel method is proposed in this paper. The complex three-dimensional (3D) geometries are imported as a 3DS format file from 3dsMax software with material and radiometric attributes. Based on 3D stylized model reconstruction of solid mesh, the 3D-geometrical solids are automatically converted into stylized models. In point-kernel calculation, the stylized source models are divided into point kernels and the mean free paths (mfp) are calculated by the intersections between shield stylized models and tracing ray. Compared with MCNP, the proposed method can implement complex 3D geometries visually, and the dose rate calculation is accurate and fast.

Assessment of CUPID code used for condensation heat transfer analysis under steam-air mixture conditions

  • Ji-Hwan Hwang;Jungjin Bang;Dong-Wook Jerng
    • Nuclear Engineering and Technology
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    • 제55권4호
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    • pp.1400-1409
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    • 2023
  • In this study, three condensation models of the CUPID code, i.e., the resolved boundary layer approach (RBLA), heat and mass transfer analogy (HMTA) model, and an empirical correlation, were tested and validated against the COPAIN and CAU tests. An improvement on HMTA model was also made to use well-known heat transfer correlations and to take geometrical effect into consideration. The RBLA was a best option for simulating the COPAIN test, having mean relative error (MRE) about 0.072, followed by the modified HMTA model (MRE about 0.18). On the other hand, benchmark against CAU test (under natural convection and occurred on a slender tube) indicated that the modified HMTA model had better accuracy (MRE about 0.149) than the RBLA (MRE about 0.314). The HMTA model with wall function and the empirical correlation underestimated significantly, having MRE about 0.787 and 0.55 respectively. When using the HMTA model, consideration of geometrical effect such as tube curvature was essential; ignoring such effect leads to significant underestimation. The HMTA and the empirical correlation required significantly less computational resources than the RBLA model. Considering that the HMTA model was reasonable accurate, it may be preferable for large-scale simulations of containment.

Thermal buckling behaviour of shear deformable functionally graded single/doubly curved shell panel with TD and TID properties

  • Kar, Vishesh R.;Panda, Subrata K.;Mahapatra, Trupti R.
    • Advances in materials Research
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    • 제5권4호
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    • pp.205-221
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    • 2016
  • In this article, the buckling responses of functionally graded curved (spherical, cylindrical, hyperbolic and elliptical) shell panels under elevated temperature load are investigated numerically using finite element steps. The effective material properties of the functionally graded shell panel are evaluated using Voigt's micromechanical model through the power-law distribution with and without temperature dependent properties. The mathematical model is developed using the higher-order shear deformation theory in conjunction with Green-Lagrange type nonlinear strain to consider large geometrical distortion under thermal load. The efficacy of the proposed model has been checked and the effects of various geometrical and material parameters on the buckling load are analysed in details.

인수분해공식의 기하학적 모델 구성에 대한 고찰 (A Study on the Composition of Geometrical Model for Factorization Formula)

  • 정영우;김부윤
    • East Asian mathematical journal
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    • 제36권2호
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    • pp.291-315
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    • 2020
  • In this study, the geometric model of 11 factorization formulas presented in the 2015 revised national curriculum was constructed and the necessary mathematical conditions were derived in the process. As a result of the study, all of the 11 factorization formulas are geometrically modeled and 12 conditions are derived in the process. However, the basic method of directly cutting and attaching a given shape was limited to not being able to make a rectangle or rectangular parallelepiped. Therefore, the problem was solved by changing the perspective and focusing on whether rectangle or rectangular parallelepiped with the same area or volume could be constructed.

기하학적 Ring 모델에 기반을 둔 협력형 MIMO 채널 시뮬레이터 (Cooperative MIMO Channel Simulation Based on the Geometrical Ring Model)

  • 양미선;김동우
    • 한국통신학회논문지
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    • 제33권3A호
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    • pp.235-239
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    • 2008
  • 본 논문에서는 협력형 MIMO (multi-input multi-output) 채널 모델의 시뮬레이션 모델을 제안한다. 여기서 기하학적 one-ring 채널 모델과 기하학적 two-ring 채널 모델을 확장시켜 서 협력형 one-ring 채널 모델을 소개한다. 먼저, 송신 노드와 수신 노드 그리고 중계 노드가 모두 정방향의 무한개의 스캐터로 둘러 쌓여 있다는 가정아래, 협력형 one-ring 채널에 대한 참조 모델의 복소 채널 이득과 상관관계 함수를 정의한다. 다음으로, 그 참조 모델의 상관관계 함수의 값을 만족하도록 하는 시뮬레이션 모델을 제안한다. 이를 위하여 본 논문에서는 MEDS(method of exact Doppler spread) 방법을 이용하며, 마지막으로, 제안된 시뮬레이션 모델과 참조 모델의 상관관계 함수의 결과를 비교함으로서 적합한 시뮬레이션 모델임을 보인다.

Geometrical dimensions effects on the seismic response of concrete gravity dams

  • Sevim, Baris
    • Advances in concrete construction
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    • 제6권3호
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    • pp.269-283
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    • 2018
  • This study presents the effects of geometrical dimensions of concrete gravity dams on the seismic response considering different base width/dam height (L/H) ratios. In the study, a concrete gravity dam with the height of 200 m is selected and finite element models of the dam are constituted including five different L/H ratios such as 0.25, 0.5, 0.75, 1.00, 1.25. All dams are modeled in ANSYS software considering dam-reservoir-foundation interaction. 1989 Loma Prieta earthquake records are applied to models in upstream-downstream direction and linear time history analyses are performed. Dynamic equilibrium equations of motions obtained from the finite element models of the coupled systems are solved by using Newmark time integration algorithm. The seismic response of the models is evaluated from analyses presenting natural frequencies, mode shapes, displacements and principal stresses. The results show that the L/H ratios considerably affect the seismic response of gravity dams. Also, the model where L/H ratio is 1.00 has more desirable results and most appropriate representation of the seismic response of gravity dams.

The Facial Expression Recognition using the Inclined Face Geometrical information

  • Zhao, Dadong;Deng, Lunman;Song, Jeong-Young
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2012년도 추계학술대회
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    • pp.881-886
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    • 2012
  • The paper is facial expression recognition based on the inclined face geometrical information. In facial expression recognition, mouth has a key role in expressing emotions, in this paper the features is mainly based on the shapes of mouth, followed by eyes and eyebrows. This paper makes its efforts to disperse every feature values via the weighting function and proposes method of expression classification with excellent classification effects; the final recognition model has been constructed.

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Economic Design of the Specification for Geometrical Quality Characteristic

  • Ma, Yizhong;Zhao, Fengyu;Xu, Jichao
    • International Journal of Quality Innovation
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    • 제2권1호
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    • pp.50-57
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    • 2001
  • The economic design of specification limits must be determined on an economic basis where we minimize total loss to society, which consists of both the producer and the consumer. Economic specification limits have been developed based on the assumption that the quality characteristic is normally distributed. Unfortunately, the assumption is not to meet some practical cases. In this paper, some non-normal distributions are considered for quality characteristic with geometrical features. An economic model for selecting the optimum specification limits on the basis of minimizing total cost is introduced. A case study is presented to illustrate the application in practice.

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