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In order to realize the resource optimization allocation in the green innovation system of China’s shipbuilding industry under the internet environment, to improve the level of green innovation and to reduce the resource consumption, a resource optimization allocation model and the corresponding allocation strategy are proposed. The model integrates and shares the innovation resource data through Internet of Things (IOT) technology, and optimizes the allocation decision by using the cooperative differential game and Particle Swarm Optimization (PSO) algorithm. At the same time, it ensures the robustness of green innovation system and realizes the optimization allocation of resources. A case study is given to illustrate the feasibility of the model. The results show that the green innovation subject can carry out strategic interaction by adjusting the allocation proportion of innovation resources through the proposed model, so as to optimize the overall green innovation benefits of the system.

In this paper, the free and forced vibration behavior of coupled composite laminated shell are investigated by using a domain decomposition method under the elastic boundary condition. The coupled shell structure is combined in the form of a double curved shell-cylindrical shell-double curved shell, and the double curved shells at both ends are combined with the cylindrical shell upside down (figure 1). The double curved shell contains the elliptical, paraboloidal and hyperbolical shells. multi-segment partitioning technique is employed to establish the theoretical model based on the first-order shear deformation theory (FSDT). Regardless of the shell types and boundary conditions, the displacement functions of each shell are expended by the orthogonal ultraspherical polynomials in the meridional direction, and by the standard Fourier series in the circumferential direction. The boundary and continue conditions are generalized by the artificial spring technology. The convergence study and numerical comparison with finite element method (FEM) demonstrates that the proposed method has good reliability and accuracy to analyze the dynamic characteristics of the coupled composite laminated shell. The effects of material properties, geometric dimension, boundary condition and external force on the coupled composite laminated shell structure are proposed with some numerical results.

In this paper, a new meshfree moving least squares-Tchebychev (MLST) shape function is proposed to analyze the free vibration characteristics of laminated composite arbitrary quadrilateral plate with hole. The plate and hole have an arbitrary quadrilateral shape. The whole plate structure is separated into the segments with arbitrary quadrilateral shape by the domain decompose method, and these segments are modeled to a square plate through the coordinate mapping. The fourth order polynomial mapping approach is used as a mapping function for the coordinate mapping. The first-order shear deformation theory (FSDT) is adopted in theoretical formulation for the free vibration analysis of laminated composite arbitrary quadrilateral plate. The boundary and continuation conditions are generalized by the artificial spring technique. All the displacement functions containing the boundary and continuation conditions are expressed by the meshfree MLST shape function, on the base of this, the governing equation of arbitrary plate with hole are obtained. Thus, the natural frequency and mode shape of the laminated composite arbitrary quadrilateral plate with hole are obtained by solving the governing equation. The accuracy and reliability of the proposed method are verified by comparison with the results of literature and ABAQUS. Through numerical verification, it can be seen that the results of the proposed method are in good agreement with those of the literature and ABAQUS. The free vibration characteristics (i.e. natural frequency and mode shape) of the laminated composite arbitrary quadrilateral plate with arbitrary quadrilateral hole under different boundary conditions are proposed through the parameter research and some examples. RECEIVED

In this paper, the free vibration characteristics of various coupled composite laminated doubly curved revolution shells are investigated under generalized boundary conditions (BCs). The joint shell structure consists of a doubly curved revolution shell–cylindrical shell–doubly curved revolution shell structure, and here, unlike previous structures, the doubly curved revolution shells are inversely joined together. In this paper, doubly curved shells such as elliptical, paraboloidal, and spherical shells are considered. The first order shear deformation theory and multi-segment partitioning technique are adopted to establish the theoretical model of coupled shell structures. Regardless of the individual shell structures and the BCs, the displacement functions of each shell segment are expanded using ultraspherical polynomials in the meridional direction and using the standard Fourier series in the circumferential direction. In order to generalize the BCs at both ends of a coupled shell and the connecting conditions at the interface, the virtual spring technique is employed. Then, the natural frequencies and mode shapes of the coupled shell structures are obtained by the Ritz method. The reliability and accuracy of the proposed method are verified by the convergence study and numerical comparison with results of the finite element method. In addition, some numerical results are also reported for the free vibration of coupled composite laminated doubly curved revolution shell structures under classical and elastic BCs, which can provide the reference data for future studies.