• 제목/요약/키워드: irregular set

검색결과 183건 처리시간 0.024초

SPECIFICATION AND CONTROLLER SYNTHESIS FOR THE HIERARCHICAL CONTROL OF FMS

  • Chang, Jin-Tae;Kim, Hun-Tai;Kang, Suk-Ho
    • Management Science and Financial Engineering
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    • 제3권2호
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    • pp.71-92
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    • 1997
  • Developing FMS controllers has been a difficult problem largely because of the variety of the system configuration. The purpose of this paper is to develop a method of building an FMS controller. The controller consists of control module and execution module. A hierarchically layered structure of these modules is proposed. The control module generates abstract-level execution requested by identifying a set of activities that can be executed without creating any irregular state. The execution module transmits the requests to physical device controllers and reports back the completion of the requests to the control module. Both of these two modules use Petri Net-based models. In this paper, a controllable Petri Net model is automatically synthesized from declarative specifications provided by a user. An execution Petri Net model for the execution module is designed to ensure the consistency between the control module and the real target system. The controller operates in MMS on TCP/IP and UNIX environment.

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Stability of a cylindrical shell with an oblique end

  • Hu, X.J.;Redekop, D.
    • Structural Engineering and Mechanics
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    • 제19권1호
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    • pp.43-53
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    • 2005
  • The linearized buckling problem is considered for an isotropic clamped-clamped cylindrical shell with an oblique end. A theoretical solution based on the Budiansky shell theory is developed, and numerical results are determined using the differential quadrature method. In formulating the solutions, the surface of the shell is developed onto a plane, and the resulting irregular domain is then mapped, using blending functions, onto a square parent domain. The analysis is carried out in the parent domain. Convergence, validation, and parametric studies are conducted for a uniform external pressure loading. Results determined are compared with finite element results. The paper ends with an appropriate set of conclusions.

기술사 마당 - 기술자료 - 도시시설물에서 미적(美的) 경관요소를 고려한 자연석 옹벽 (Natural Wall Systems-Esthetic View Element in a Downtown Facilities)

  • 조규영;노금두;서범석
    • 기술사
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    • 제42권4호
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    • pp.55-61
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    • 2009
  • Retaining wall is a structure to stabilize the land slope as vertical retaining wall have constructed to make efficiency use of downtown area. Recently to commune with nature and refine a apartment and structure, natural friendly relations for retaining walls are tried to construct. The surface of the concrete walls are weave in various figures and colours, and in some places plant a shrub. Laying a landscape stone which have disclose a plane nature one means keeping up the natural slope, constructively safely set a anchor in front side and rear side wall between the natural stone, plant shrub or ground coverings to give shape into a rock. Natural stone is exposed of surface and planting the gardening, to be a type of natural friendly relations however that will be recycled. The size of blasted nature stone which is irregular become more natural type of one.

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인쇄체 영문의 구문론적 인식 (A CHARACTER RECOGNITION SYSTEM BASED ON SYNTACTIC APPROACH)

  • 박동춘;박성한
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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    • pp.1598-1601
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    • 1987
  • This paper proposes a new set of topological features (primitives) for use with a syntactic recognizer for high-accuracy recognition of printed alphanumeric characters. The recognition is accomplished on nine character groups, where each group has different combinations of four feature points. A skeleton enhancement eliminating isolated points and smoothing irregular points is developed. The tree automata processed in parallel enables the realization of high-recognition speeds and font-type independent recognition. The proposed character recognition system is tested for alphanumeric character fonts of dot matrix printer and plotter using IBM-PC/XT.

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Modeling of Groundwater Flow Using the Element-Free Galerkin (EFG) Method

  • Park, Yu-Chul;Darrel I. Leap
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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    • pp.77-80
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    • 2001
  • The element-free Galerkin (EFG) method is one of meshless methods, which is an efficient method of modeling problems of fluid or solid mechanics with complex boundary shapes and large changes in boundary conditions. This paper discusses the theory of the EFG method and its applications to modeling of groundwater flow. In the EFG method, shape functions are constructed based on the moving least square (MLS) approximation, which requires only set of nodes. The EFG method can eliminate time-consuming mesh generation procedure with irregular shaped boundaries because it does not require any elements. The coupled EFG-FEM technique was introduced to treat Dirichlet boundary conditions. A computer code EFGG was developed and tested for the problems of steady-state and transient groundwater flow in homogeneous or heterogeneous aquifers. The accuracy of solutions by the EFG method was similar to that by the FEM. The EFG method has the advantages in convenient node generation and flexible boundary condition implementation.

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Analysis of light-frame, low-rise buildings under simulated lateral wind loads

  • Fischer, C.;Kasal, B.
    • Wind and Structures
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    • 제12권2호
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    • pp.89-101
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    • 2009
  • The Monte Carlo procedure was used to simulate wind load effects on a light-frame low-rise structure of irregular shape and a main wind force resisting system. Two analytical models were studied: rigid-beam and rigid-plate models. The models assumed that roof diaphragms were rigid beam or rigid plate and shear walls controlled system behavior and failure. The parameters defining wall stiffness, including imperfections, were random and included wall stiffness, wall capacity and yield displacements. The effect of openings was included in the simulation via a set of discrete multipliers with uniform distribution. One and two-story buildings were analyzed and the models can be expanded into multiple-floor structures provided that the assumptions made in this paper are not violated.

Vibration analysis of plates with curvilinear quadrilateral domains by discrete singular convolution method

  • Civalek, Omer;Ozturk, Baki
    • Structural Engineering and Mechanics
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    • 제36권3호
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    • pp.279-299
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    • 2010
  • A methodology on application of the discrete singular convolution (DSC) technique to the free vibration analysis of thin plates with curvilinear quadrilateral platforms is developed. In the proposed approach, irregular physical domain is transformed into a rectangular domain by using geometric coordinate transformation. The DSC procedures are then applied to discretization of the transformed set of governing equations and boundary conditions. For demonstration of the accuracy and convergence of the method, some numerical examples are provided on plates with different geometry such as elliptic, trapezoidal having straight and parabolic sides, sectorial, annular sectorial, and plates with four curved edges. The results obtained by the DSC method are compared with those obtained by other numerical and analytical methods. The method is suitable for the problem considered due to its generality, simplicity, and potential for further development.

Multiple Person Tracking based on Spatial-temporal Information by Global Graph Clustering

  • Su, Yu-ting;Zhu, Xiao-rong;Nie, Wei-Zhi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권6호
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    • pp.2217-2229
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    • 2015
  • Since the variations of illumination, the irregular changes of human shapes, and the partial occlusions, multiple person tracking is a challenging work in computer vision. In this paper, we propose a graph clustering method based on spatio-temporal information of moving objects for multiple person tracking. First, the part-based model is utilized to localize individual foreground regions in each frame. Then, we heuristically leverage the spatio-temporal constraints to generate a set of reliable tracklets. Finally, the graph shift method is applied to handle tracklet association problem and consequently generate the completed trajectory for individual object. The extensive comparison experiments demonstrate the superiority of the proposed method.

역경계요소법에 근거한 근접 음향 홀로그래피에서 강체 산란체의 이용 (Use of Rigid Scattering Body in the use of NAH based on the inverse BEM)

  • 김성일;정지훈;이정권
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.486-489
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    • 2004
  • The NAH based on the inverse BEM is used to reconstruct the source field, which is advantageous in dealing with the irregular source. In the implementation of this technique, a large number of pressure measurements is required because an over-determined pressure data set is required. These conditions accordingly cause the increase of measurement time and associated effort along with the error due to mal-positioning. The purpose of this study is to reduce such inconveniences: Instead of increasing the number of field pressure data, the number of transfer paths between the source and the receiver is increased by placing rigid scattering body in-between the source and receiver. For validating the usefulness and effectiveness of the method, the numerical analyses of interior problem are demonstrated. As a result, it is thought that the proposed method enables the measurement at smaller number of sensor positions and the monitoring of surface vibration with less experimental effects than before.

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Development of a distributed rainfall-runoff model with TIN-based topographic representation and its application to an analysis of spatial variability of soil properties on runoff response

  • Tachikawa, Yasuto;Shiiba, Michiharu
    • 한국수자원학회논문집
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    • 제33권S1호
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    • pp.28-36
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    • 2000
  • A TIN, Triagulated Irregular Network, based topographic modeling method and a distributed rainfall-runoff model using the topographic representation is presented. In the TIN based topographic representation, a watershed basin is modeled as a set of contiguous non-overlapping triagular facets : the watershed basin is subdivided according to streamlines to deal with water movement one-dimensionally ; and each partitioned catchment is approximated to a slope element having a quasi-three-dimensional shape by using cubic spline functions. On an approximated slope element, water movement is represented by combined surface-subsurface kinematic wave equations considering a change of slope gradient and slope width. By using the distributed rainfall-runoff model, the effects of spatial variability of soil properties on runoff response are examined.

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