• Title/Summary/Keyword: three dimensional shape

Search Result 1,471, Processing Time 0.028 seconds

Lip Shape Synthesis of the Korean Syllable for Human Interface (휴먼인터페이스를 위한 한글음절의 입모양합성)

  • 이용동;최창석;최갑석
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.19 no.4
    • /
    • pp.614-623
    • /
    • 1994
  • Synthesizing speech and facial images is necessary for human interface that man and machine converse naturally as human do. The target of this paper is synthesizing the facial images. In synthesis of the facial images a three-dimensional (3-D) shape model of the face is used for realizating the facial expression variations and the lip shape variations. The various facial expressions and lip shapes harmonized with the syllables are synthesized by deforming the three-dimensional model on the basis of the facial muscular actions. Combications with the consonants and the vowels make 14.364 syllables. The vowels dominate most lip shapes but the consonants do a part of them. For determining the lip shapes, this paper investigates all the syllables and classifies the lip shapes pattern according to the vowels and the consonants. As the results, the lip shapes are classified into 8 patterns for the vowels and 2patterns for the consonants. In advance, the paper determines the synthesis rules for the classified lip shape patterns. This method permits us to obtain the natural facial image with the various facial expressions and lip shape patterns.

  • PDF

Centrifugal Impeller Blade Shape Optimization Through Numerical Modeling

  • Bellary, Sayed Ahmed Imran;Samad, Abdus
    • International Journal of Fluid Machinery and Systems
    • /
    • v.9 no.4
    • /
    • pp.313-324
    • /
    • 2016
  • Surrogate model based shape optimization methodology to enhance performance of a centrifugal pump has been implemented in this work. Design variables, such as blade number and blade angles defining the pump impeller blade shape were selected and a three-level full factorial design approach was used for efficiency enhancement. A three-dimensional simulation using Reynolds-averaged Navier Stokes (RANS) equations for the performance analysis was carried out after designing the geometries of the impellers at the design points. Standard $k-{\varepsilon}$ turbulence model was used for steady incompressible flow simulations. The optimized impeller incurred lower losses by shifting the trailing edge towards the impeller pressure side. It is observed that the surrogates are problem dependent and most accurate surrogate does not deliver the best design always.

A numerical study on the seepage failure by heave in sheeted excavation pits

  • Koltuk, Serdar;Fernandez-Steeger, Tomas M.;Azzam, Rafig
    • Geomechanics and Engineering
    • /
    • v.9 no.4
    • /
    • pp.513-530
    • /
    • 2015
  • Commonly, the base stability of sheeted excavation pits against seepage failure by heave is evaluated by using two-dimensional groundwater flow models and Terzaghi's failure criterion. The objective of the present study is to investigate the effect of three-dimensional groundwater flow on the heave for sheeted excavation pits with various dimensions. For this purpose, the steady-state groundwater flow analyses are performed by using the finite element program ABAQUS 6.12. It has been shown that, in homogeneous soils depending on the ratio of half of excavation width to embedment depth b/D, the ratio of safety factor obtained from 3D analyses to that obtained from 2D analyses $FS_{(3D)}/FS_{(2D)}$ can reach up to 1.56 and 1.34 for square and circular shaped excavations, respectively. As failure body, both an infinitesimal soil column adjacent to the wall (Baumgart & Davidenkoff's criterion) and a three-dimensional failure body with the width suggested by Terzaghi for two-dimensional cases are used. It has been shown that the ratio of $FS_{(Terzaghi)}/FS_{(Davidenkoff)}$ varies between 0.75 and 0.94 depending on the ratio of b/D. Additionally, the effects of model size, the shape of excavation pit and anisotropic permeability on the heave are studied. Finally, the problem is investigated for excavation pits in stratified soils, and important points are emphasized.

Three Dimensional FEM Simulation for Spinning of Non-circular Fibers

  • Kim, Heejae;Chung, Kwansoo;Youn, Jae-Ryoun
    • Fibers and Polymers
    • /
    • v.1 no.1
    • /
    • pp.37-44
    • /
    • 2000
  • A finite element method is employed fer a flow analysis of the melt spinning process of a non-circular fiber, a PET(polyethylene terephthalate) filament. The flow field is divided into two regions of die channel and spin-line. A two dimensional analysis is used for the flow within the die channel and a three dimensional analysis fur the flow along the spin-line. The Newtonian fluid is assumed for the PET melt and material properties are considered to be constant except for the viscosity. Effects of gravitation, air drag force, and surface tension are neglected. Although the spin-line length is 4.5 m only five millimeters from the spinneret are evaluated as the domain of the analysis. Isothermal and non-isothermal cases are studied fer the flow within the die channel. The relationship between the mass flow rate and the pressure gradient is presented for the two cases. Three dimensional flow along the spin-line is obtained by assuming isothermal conditions. It is shown that changes in velocity and cross-sectional shape occur mostly in the region of 1mm from the die exit.

  • PDF

Analysis of Mechanical Characteristics of Polymer Sandwich Panels Containing Injection Molded and 3D Printed Pyramidal Kagome Cores

  • Yang, K.M.;Park, J.H.;Choi, T.G.;Hwang, J.S.;Yang, D.Y.;Lyu, M.-Y.
    • Elastomers and Composites
    • /
    • v.51 no.4
    • /
    • pp.275-279
    • /
    • 2016
  • Additive manufacturing or 3D printing is a new manufacturing process and its application is getting growth. However, the product qualities such as mechanical strength, dimensional accuracy, and surface quality are low compared with conventional manufacturing process such as molding and machining. In this study not only mechanical characteristics of polymer sandwich panel having three dimensional core layer but also mechanical characteristics of core layer itself were analyzed. The shape of three dimensional core layer was pyramidal kagome structure. This core layer was fabricated by two different methods, injection molding with PP resin and material jetting type 3D printing with acrylic photo curable resin. The material for face sheets in the polymer sandwich panel was PP. Maximum load, stiffness, and elongation at break were examined for core layers fabricated by two different methods and also assembled polymer sandwich panels. 3D printed core showed brittle behavior, but the brittleness decreased in polymer sandwich panel containing 3D printed core. The availability of 3D printed article for the three dimensional core layer of polymer sandwich panel was verified.

A study on relative velocity approach for shape desing to cylindrical cam with rotating roller follower on faced-vertical axes (직교축상의 회전운동용 롤러 종동절을 수반하는 원통형 캠의 형상설계를 위한 상대속도법에 관한 연구)

  • 김성원;신중호;강동우;장세원
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2000.11a
    • /
    • pp.612-615
    • /
    • 2000
  • Cam mechanism is one of the common devices used in many automatic machinery. Specially cylindrical cam generates three dimensional motions. Thus, the shape design procedures must have high accuracy. This paper proposes the shape design procedure for a cylindrical cam and follower mechanism using a relative velocity method. The relative velocity method and the coordinate transformation are used to find a contact point between the cam and the follower. Also, the full shape of the cylindrical cam can be generated by using the geometric relationships and the contact constraints. As a result, this paper presents an example for the shape design of the cylindrical cam in order to prove the accuracy of the design procedures.

  • PDF

Development of a Platform for Realistic Garment Drape Simulation

  • Kim, Sung-Min;Park, Chang-Kyu
    • Fibers and Polymers
    • /
    • v.7 no.4
    • /
    • pp.436-441
    • /
    • 2006
  • An integrated platform for garment drape simulation system has been developed. In this system, garment patterns from conventional two-dimensional CAD systems can be assembled into a three-dimensional garment on a parametrically resizable realistic human body model. A fast and robust particle-based physical calculation engine has been developed for garment shape generation. Then a series of geometric and graphical techniques were applied to create realistic impressions on simulated garments. This system can be used as the rapid prototyping tool for garments in the future quick-response system.

REDUCTION METHOD APPLIED TO THE NONLINEAR BIHARMONIC PROBLEM

  • Jung, Tacksun;Choi, Q-Heung
    • Korean Journal of Mathematics
    • /
    • v.18 no.1
    • /
    • pp.87-96
    • /
    • 2010
  • We consider the semilinear biharmonic equation with Dirichlet boundary condition. We give a theorem that there exist at least three nontrivial solutions for the semilinear biharmonic boundary value problem. We show this result by using the critical point theory, the finite dimensional reduction method and the shape of the graph of the corresponding functional on the finite reduction subspace.

NUMBER OF THE NONTRIVIAL SOLUTIONS OF THE NONLINEAR BIHARMONIC PROBLEM

  • Jung, Tacksun;Choi, Q-Heung
    • Korean Journal of Mathematics
    • /
    • v.18 no.2
    • /
    • pp.201-211
    • /
    • 2010
  • We investigate the number of the nontrivial solutions of the nonlinear biharmonic equation with Dirichlet boundary condition. We give a theorem that there exist at least three nontrivial solutions for the nonlinear biharmonic problem. We prove this result by the finite dimensional reduction method and the shape of the graph of the corresponding functional on the finite reduction subspace.

Two-dimensional object contour tracking by a force controlled manipulator

  • Choi, Myoung-Hwan;Ko, Myoung-Sam;Lee, Bum-Hee
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1987.10a
    • /
    • pp.892-897
    • /
    • 1987
  • The ability of a robotic manipulator to recognize the shape of an object by feeling its band around the object is useful in many applications. Two-dimensional object contour tracking by force feedback is described. The system consists of IBM PC/AT, PUMA 560 manipulator, PUMA controller and a tip sensor. Position control is accomplished by using VAL command and the unmodified PUMA controller. A contour tracking algorithm is developed and tested on three different types of objects. The experimental results show that the objects' shapes can be successfully identified.

  • PDF