• 제목/요약/키워드: Body coordinate

검색결과 284건 처리시간 0.023초

3차원 미니밴 형상 주위의 비압축성 점성 유동 해석 (Incompressible Viscous Flow Analysis Around a Three Dimensional Minivan-Like Body)

  • 정영래;박원규;박영준;김종섭;홍성훈
    • 한국전산유체공학회지
    • /
    • 제2권1호
    • /
    • pp.46-53
    • /
    • 1997
  • The flow field around a three dimensional minivan-like body has been simulated. This study solves 3-D unsteady incompressible Navier-Stokes equations on a non-orthogonal curvilinear coordinate system using second-order accurate schemes for the time derivatives, and third/second-order scheme for the spatial derivatives. The Marker-and-Cell concept is applied to efficiently solve continuity equation. A H-H type of multi-block grid system is generated around a three dimensional minivan-like body. Turbulent flows have been modeled by the Baldwin-Lomax turbulent model. To validate present procedure, the flows around the Ahmed body with 12.5° of slant angle are simulated. A good agreement with other numerical results is achived. After code validation, the flows around a mimivan-like body are simulated. The simulation shows three dimensional vortex-pair just behind body. The flow separation is also observed on the rear of the body. It has concluded that the results of present study properly agreed with physical flow phenomena.

  • PDF

외모(外貌)에 있어서 가상(假想) 3D 패션 코디네이션에 대(對)한 질적(質的) 연구(硏究) (A Qualitative Study about Coordination system of 3D Virtual Model)

  • 신효정;김효숙;최창석
    • 패션비즈니스
    • /
    • 제7권2호
    • /
    • pp.143-155
    • /
    • 2003
  • The purpose of this study were to investigate 1) Values placed upon born hereditary appearance and a made up appearance, 2)examined for points of body and clothing and 3)discrepancy in opinions about Coordination system of 3D Virtual Model This study chose qualitative research approach in-depth interviews were from December 12, 2002, to February 20, 2003. The subjects of the study were 12 women aged in twenties 12 women aged over forty. The results of this study were as follows. 1. Women aged in their twenties defined appearance as follows. there are important a made up appearance, Appearance is looking at point of view from body shape to face, makeup, hair style, body image, cosmetic surgery, clothing and is looking at the whole point of view from hair to tiptoe. This seems to include attitude, personality, behavior, images, and feeling. 2. Regarding body image Women aged in their twenties prefer a slender figure. Women aged in their twenties exerts all possible efforts to have an attractive body through dress well. 3. Regarding body image Women aged in their twenties prefer coordinate to system of 3D virtual model.

Standard Terminology System Referenced by 3D Human Body Model

  • Choi, Byung-Kwan;Lim, Ji-Hye
    • Journal of information and communication convergence engineering
    • /
    • 제17권2호
    • /
    • pp.91-96
    • /
    • 2019
  • In this study, a system to increase the expressiveness of existing standard terminology using three-dimensional (3D) data is designed. We analyze the existing medical terminology system by searching the reference literature and perform an expert group focus survey. A human body image is generated using a 3D modeling tool. Then, the anatomical position of the human body is mapped to the 3D coordinates' identification (ID) and metadata. We define the term to represent the 3D human body position in a total of 12 categories, including semantic terminology entity and semantic disorder. The Blender and 3ds Max programs are used to create the 3D model from medical imaging data. The generated 3D human body model is expressed by the ID of the coordinate type (x, y, and z axes) based on the anatomical position and mapped to the semantic entity including the meaning. We propose a system of standard terminology enabling integration and utilization of the 3D human body model, coordinates (ID), and metadata. In the future, through cooperation with the Electronic Health Record system, we will contribute to clinical research to generate higher-quality big data.

인장계규식 해양구조물의 동적응답해석(I) (A Dynamic Response Analysis of Tension Leg Platforms in Waves (I))

  • 구자삼;김진하;이창호
    • 한국해양공학회지
    • /
    • 제9권1호
    • /
    • pp.161-172
    • /
    • 1995
  • A numerical procedure is described fro predicting the motion and structural responses of tension leg platforms(TLPs) in waves. The developed numerical approach is based on a combination of a three dimensional source distribution method and the dynamic response analysis method, in which the superstructure of TLPs is assumed flexible instead of the rigid body assumption used in tow-step analysis method. Both the hydrodynamic interactions among TLP members, such as columns and pontoons, and the structural whole structure are formulated using element-fixed coordinate systems which have the origin at the node of the each hull element and move parallel to a space-fixed coordinate system. Numerical results are compared with the experimental and numerical ones, which are obtained in the literature, concerning the motion and structural responses of a TLP in waves. The results of comparison confirmed the validity of the proposed approach.

  • PDF

가중치를 고려한 자동차 서브프레임의 인증 알고리즘 구현 (Development of Registration Algorithm considering Coordinate Weights for Automobile Sub-Frame Assembly)

  • 이광일;양승한;이영문
    • 한국기계가공학회지
    • /
    • 제3권4호
    • /
    • pp.7-12
    • /
    • 2004
  • Inspection and analysis are essential process to determine whether a completed product is in given specification or not. Analysis of products with very complicated shape is difficult to carry out direct comparison between inspected coordinate and designed coordinates. So process called as matching or registrations is needed to solve this problem. By defining error between two coordinates and minimizing the error, registration is done. Registration consists of translation, rotation and scale transformations. Error must be defined to express feature of inspected product. In this paper, registration algorithm is developed to determine pose of sub-frame at assembly with body of automobile by defining error between two coordinates considering geometric feature of sub-frame.

  • PDF

MATLAB을 이용한 유연 다물체 시스템의 해석 및 제어 (Analysis and Control of the Flexible Multibody System Using MATLAB)

  • 정성필;박태원
    • 대한기계학회논문집A
    • /
    • 제32권5호
    • /
    • pp.437-443
    • /
    • 2008
  • In this paper, analysis and control of the flexible multibody system using MATLAB is presented. The equations of motion of a flexible body are derived in terms of the modal coordinate. The rigid-flexible multibody dynamic solver is developed. Finite element information required to analyze motion of flexible bodies is imported from ANSYS. The modified finite element data, such as modal mass matrix, modal stiffness matrix and constraint mode shapes, is calculated in the solver. Since the solver is developed using MATLAB, it is very easy to connect with SIMULINK which is widely used to control motion of the multibody system. Several simulations are implemented to verify the developed solver. A control example is carried out and the usefulness of the developed solver is demonstrated.

Numerical Analysis of Evolution of Thermal Stratification in a Curved Piping System

  • Park, Seok-Ki;Nam, Ho-Yun;Jo, Jong-Chull
    • Nuclear Engineering and Technology
    • /
    • 제32권2호
    • /
    • pp.169-179
    • /
    • 2000
  • A detailed numerical analysis of the evolution of thermal stratification in a curved piping system in a nuclear power plant is performed. A finite volume based thermal-hydraulic computer code has been developed employing a body-fitted, non-orthogonal curvilinear coordinate for this purpose. The cell-centered, non-staggered grid arrangement is adopted and the resulting checkerboard pressure oscillation is prevented by the application of momentum interpolation method. The SIMPLE algorithm is employed for the pressure and velocity coupling, and the convection terms are approximated by a higher-order bounded scheme. The thermal-hydraulic computer code developed in the present study has been applied to the analysis of thermal stratification in a curved duct and some of the predicted results are compared with the available experimental data. It is shown that the predicted results agree fairly well with the experimental measurements and the transient formation of thermal stratification in a curved duct is also well predicted.

  • PDF

다중 자세방위기준장치 기반 사람/보행로봇의 동작추적 및 위치추정 (Multi-Attitude Heading Reference System-based Motion-Tracking and Localization of a Person/Walking Robot)

  • 조성윤
    • 제어로봇시스템학회논문지
    • /
    • 제22권1호
    • /
    • pp.66-73
    • /
    • 2016
  • An Inertial Measurement Unit (IMU)-based Attitude and Heading Reference System (AHRS) can calculate attitude and heading information with long-term accuracy and stability by combining gyro, accelerometer, and magnetic compass signals. Motivated by this characteristic of the AHRS, this paper presents a Motion-Tracking and Localization (MTL) method for a person or walking robot using multi-AHRSs. Five AHRSs are attached to the two calves, two thighs, and waist of a person/walking robot. Joints, links, and coordinate frames are defined on the body. The outputs of the AHRSs are integrated with link data. In addition, a supporting foot is distinguished from a moving foot. With this information, the locations of the joints on the local coordinate frame are calculated. The experimental results show that the presented MTL method can track the motion of and localize a person/walking robot with long-term accuracy in an infra-less environment.

2차원 익렬유동의 Navier-Stokes 해석 (Navier-Stokes Analysis of Two Dimensional Cascade Flow)

  • 정희택;백제현
    • 대한기계학회논문집
    • /
    • 제16권2호
    • /
    • pp.313-324
    • /
    • 1992
  • Two-dimensional Navier-Stokes code has been developed for analysis of turbomachinery blade rows and other internal flows. The Navier-Stokes equations are written in a Cartesian coordinate system, then mapped into a generalized body-fitted coordinate system. All direction of viscous terms are incorporated and turbulent effects are modeled using the Baldwin-Lomax algebraic model. Equation are discretized using finite difference method on the C-type grids and solved using implicit LU-ADI decomposition scheme. Calculations are made at a VKI turbine cascade flow in a transonic wind-tunnel and compared to experimental data. Present numerical scheme is shown to be in good agreement with the previous experimental results and simulates the two-dimensional viscous flow phenomena.

시점 불변인 특징과 확률 그래프 모델을 이용한 인간 행위 인식 (Human Activity Recognition using View-Invariant Features and Probabilistic Graphical Models)

  • 김혜숙;김인철
    • 정보과학회 논문지
    • /
    • 제41권11호
    • /
    • pp.927-934
    • /
    • 2014
  • 본 논문에서는 Kinect와 같은 RGB-D 센서를 이용하여 사람의 3차원 신체 포즈 스트림 데이터를 생성하고, 이로부터 사람의 일상 행위를 효과적으로 인식하는 방법을 제안한다. Kinect SDK나 OpenNI에서 제공하는 실시간 신체 포즈 데이터는 Kinect 중심의 3차원 데카르트 좌표계로 표현되기 때문에, 시점 변화 문제와 크기 변화 문제를 겪을 가능성이 높다. 이러한 문제를 해결하고 시점 및 크기 불변인 특징을 얻기 위해, 본 논문에서는 신체 포즈 데이터를 실험자의 골반을 원점으로 하는 구면 좌표계로 변환하고 실험자의 팔 길이를 이용한 크기 정규화를 수행한다. 또한, 본 논문에서는 확률 그래프 모델 중 하나인 은닉 조건부 랜덤 필드를 이용하여, 고수준의 일상 행위들이 내포하는 다양한 내부 구조를 효과적으로 표현한다. 두 가지 데이터 집합 KAD-70과 CAD-60을 이용한 실험을 통해, 본 논문에서 제안한 행위 인식 방법과 구현 시스템의 높은 인식 성능을 확인하였다.