The Experts below are selected from a list of 192054 Experts worldwide ranked by ideXlab platform

Omer Civalek - One of the best experts on this subject based on the ideXlab platform.

  • a four node discrete singular convolution for geometric transformation and its application to numerical solution of vibration problem of arbitrary straight sided quadrilateral plates
    Applied Mathematical Modelling, 2009
    Co-Authors: Omer Civalek
    Abstract:

    A four-node discrete singular convolution (DSC) method is developed for free vibration analysis of arbitrary straight-sided quadrilateral plates. The straight-sided quadrilateral domain is mapped into a square domain in the Computational Space using a four-node element. By using the geometric transformation, the governing equations and boundary conditions of the plate are transformed from the physical domain into a square Computational domain. Numerical examples illustrating the accuracy and convergence of the DSC method for skew, trapezoidal, rhombic and arbitrary quadrilateral plates are presented. The results obtained by DSC method were compared with those obtained by the other numerical methods.

  • Analysis of shear deformable laminated composite trapezoidal plates
    Materials & Design, 2009
    Co-Authors: Murat Gürses, Omer Civalek, Hakan Ersoy, Okyay Kiracioglu
    Abstract:

    This paper presents the discrete singular convolution (DSC) method for the free vibration analysis of laminated trapezoidal plates. The plate formulation is based on first-order shear deformation theory (FSDT). The straight-sided trapezoidal domain is mapped into a square domain in the Computational Space using a four-node element by using the geometric transformation. The frequency parameters are obtained for symmetric angle-ply and cross-ply laminated trapezoidal plate. The accuracy of the present method is demonstrated by comparing with numerical and analytical solutions available in the literature.

Jeffrey R Koseff - One of the best experts on this subject based on the ideXlab platform.

  • a non staggered grid fractional step method for time dependent incompressible navier stokes equations in curvilinear coordinates
    Journal of Computational Physics, 1994
    Co-Authors: Yan Zang, Robert L Street, Jeffrey R Koseff
    Abstract:

    A numerical method for solving three-dimensional, time-dependent incompressible Navier-Stokes equations in curvilinear coordinates is presented. The non-staggered-grid method originally developed by C. M. Rhie and W. L. Chow (AIAAJ.21, 1525 (1983)) for steady state problems is extended to compute unsteady flows. In the Computational Space, the Cartesian velocity components and the pressure are defined at the center of a control volume, while the volume fluxes are defined at the mid-point on their corresponding cell faces. The momentum equations are integrated semi-implicitly by the approximate factorization technique. The intermediate velocities are interpolated onto the faces of the control volume to form the source terms of the pressure Poisson equation, which is solved iteratively with a multigrid method. The compatibility condition of the pressure Poisson equation is satisfied in the same manner as in a staggered-grid method; mass conservation can be satisfied to machine accuracy. The pressure boundary condition is derived from the momentum equations. Solutions of both steady and unsteady problems including the large eddy simulation of a rotating and stratified upwelling flow in an irregular container established the favorable accuracy and efficiency of the present method.

Wen Chen - One of the best experts on this subject based on the ideXlab platform.

  • Free Vibration Analysis of Curvilinear Quadrilateral Plates by the Differential Quadrature Method
    Journal of Computational Physics, 2000
    Co-Authors: Chang Shu, Wen Chen
    Abstract:

    A methodology for applying the differential quadrature (DQ) method to the free vibration analysis of arbitrary quadrilateral plates is developed. In our approach, the irregular physical domain is transformed into a rectangular domain in the Computational Space. The governing equation and the boundary conditions are also transformed into relevant forms in the Computational Space. Then all the computations are based on the Computational domain. As compared to the approach proposed by C. W. Bert and M. Malik (Int. J. Mech. Sci.38, 589 (1996)), the present approach requires much less Computational effort and virtual storage. In addition, the present work uses a simple and convenient way to implement clamped and simply supported boundary conditions. An exact mapping technique is used to perform the coordinate transformation in this study. Some numerical examples are provided to show the Computational efficiency of the present scheme.

Yan Zang - One of the best experts on this subject based on the ideXlab platform.

  • a non staggered grid fractional step method for time dependent incompressible navier stokes equations in curvilinear coordinates
    Journal of Computational Physics, 1994
    Co-Authors: Yan Zang, Robert L Street, Jeffrey R Koseff
    Abstract:

    A numerical method for solving three-dimensional, time-dependent incompressible Navier-Stokes equations in curvilinear coordinates is presented. The non-staggered-grid method originally developed by C. M. Rhie and W. L. Chow (AIAAJ.21, 1525 (1983)) for steady state problems is extended to compute unsteady flows. In the Computational Space, the Cartesian velocity components and the pressure are defined at the center of a control volume, while the volume fluxes are defined at the mid-point on their corresponding cell faces. The momentum equations are integrated semi-implicitly by the approximate factorization technique. The intermediate velocities are interpolated onto the faces of the control volume to form the source terms of the pressure Poisson equation, which is solved iteratively with a multigrid method. The compatibility condition of the pressure Poisson equation is satisfied in the same manner as in a staggered-grid method; mass conservation can be satisfied to machine accuracy. The pressure boundary condition is derived from the momentum equations. Solutions of both steady and unsteady problems including the large eddy simulation of a rotating and stratified upwelling flow in an irregular container established the favorable accuracy and efficiency of the present method.

Jay Lee - One of the best experts on this subject based on the ideXlab platform.

  • a blockchain enabled cyber physical system architecture for industry 4 0 manufacturing systems
    Manufacturing letters, 2019
    Co-Authors: Jay Lee, Moslem Azamfa, Jaskara Singh
    Abstract:

    Abstract Cyber-Physical Production Systems (CPPSs) are complex manufacturing systems which aim to integrate and synchronize machine world and manufacturing facility to the cyber Computational Space. However, having intensive interconnectivity and a Computational platform is crucial for real-world implementation of CPPSs. In this paper, the potential impacts of blockchain technology in development and realization of real-world CPPSs are discussed. A unified three-level blockchain architecture is proposed as a guideline for researchers and industries to clearly identify the potentials of blockchain and adapt, develop, and incorporate this technology with their manufacturing developments towards Industry 4.0.

  • Cyber-physical systems architecture for self-aware machines in industry 4.0 environment
    IFAC Proceedings Volumes (IFAC-PapersOnline), 2015
    Co-Authors: Behrad Bagheri, Hung-an Kao, Shanhu Yang, J.h. Lee, Jay Lee
    Abstract:

    The recently emerged methodologies for interconnected systems such as cyber-physical systems are focused to closely monitor the information and synchronize it between the physical connected systems and cyber Computational Space. Depending on the physical system being monitored, the approach for designing and implementing the framework for interconnect systems might differ. In manufacturing industry, utilizing advanced analytics over a systematic deployment of cyber-physical system provides network of machines with ability to perform more efficiently, collaboratively and resiliently. Such transformation can takes the manufacturing industry into the next level of evolution namely called Industry 4.0. In this paper, a unified framework for integrating CPS in manufacturing is presented. Then an adaptive clustering method as an advanced analytical method for interconnected systems will be described and at the end of the paper a case study of self-aware machines by CPS integration is presented.

  • A Cyber-Physical Systems architecture for Industry 4.0-based manufacturing systems
    Manufacturing Letters, 2015
    Co-Authors: J.h. Lee, Behrad Bagheri, Jay Lee, Hung-an Kao
    Abstract:

    Recent advances in manufacturing industry has paved way for a systematical deployment of Cyber-Physical Systems (CPS), within which information from all related perspectives is closely monitored and synchronized between the physical factory floor and the cyber Computational Space. Moreover, by utilizing advanced information analytics, networked machines will be able to perform more efficiently, collaboratively and resiliently. Such trend is transforming manufacturing industry to the next generation, namely Industry 4.0. At this early development phase, there is an urgent need for a clear definition of CPS. In this paper, a unified 5-level architecture is proposed as a guideline for implementation of CPS.