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In this paper, we derive the weak form for clamped plates composed of incompressible neo-Hookean material from the uniformly valid asymptotic plate theory. By using the finite-element software COMSOL, we study the numerical solutions of the weak form. We show the accuracy and the efficiency of the weak form by comparing the numerical results for the two-dimensional weak form and a three-dimensional model. As a basis for comparison we choose numerical values of the displacement, the second Piola–Kirchhoff stress, and the Green–Lagrange strain at the bottom. The numerical simulations are performed for three different cases of thickness–span ratios, including (1) very thin plate, (2) thin plate, and (3) moderately thick plate. The results show that the uniformly valid plate theory is a reliable and implementable plate theory for even moderately thick plates with large deformations.

This article takes the Guangdong Province of China as the research object and uses the difference-in-difference model to evaluate the impact of smart city construction on the quality of public occupational health and intercity differences. The obtained results show that smart city construction significantly improves the quality of public occupational health, and it is still valid after a series of robustness tests. The effect of this policy is stronger in cities that belong to the Pearl River Delta region or sub-provincial level cities. This study indicates that the central government should improve the pilot evaluation system and the performance appraisal mechanism of smart cities from the perspective of top-level design during the process of promoting smart city construction, which aims to correctly guide local governments to promote the construction of smart cities. To achieve the full improvement effect of smart city construction on the quality of public occupational health, local governments should implement smart city strategies in a purposeful and planned way according to the actual situation of the development of the jurisdiction.

To coordinate safety and development is a key issue for Chinese government to consider in advancing the modernization of the national governance system and governance capacity. Based on the data from the government work reports of 31 provinces (autonomous regions and municipalities) of China and 21 cities in Guangdong Province of China from 2001 to 2019, this paper examines the impact of local economic growth target setting on the quality of public occupational health from two perspectives, the first is economic growth target constraint and the second is economic growth target gap between countries and provinces or between provinces and cities. The results show that economic growth target constraint and gap have a significant impact on the quality of public occupational health, and a "U-shaped" trend is presented at both provincial level and city level, which firstly promotes and then inhibits. Those conclusions are still valid after the method of instrumental variables, generalized method of moments and other robustness tests. This paper for the first time shows the impact of economic growth management by objectives in the field of occupational health and provides useful inspiration for further optimizing government management by objectives, improving the quality of public occupational health and realizing high-quality economic development.

This paper studies the axisymmetric deformations of a nonlinearly hyperelastic tube subjected to axial compression. We aim at investigating the critical buckling stresses and modes, deriving the analytical solutions for the post-bifurcation deformations and studying the imperfection sensitivity. For a general isotropic hyperelastic tube, a coupled series-asymptotic method is utilized to derive two simplified model equations with specified constraints on the tube geometry. Then, we specialize to the Blatz–Ko material. With greased end conditions, through linear bifurcation analysis, we obtain the critical stress values and the corresponding mode numbers. The analytical solutions for the post-bifurcation states are constructed by the multiple scales method. By examining the solution behavior in the post-bifurcation regime, it is found that a thick tube could be considerably softer than a thin one. The singularities theory is used to consider the imperfection sensitivity, which reveals the mechanism is the existence of two modes corresponding to the same critical stress. Numerical solutions are also obtained which confirm the validity of the analytical solutions.

In this Note, we study the corner instabilities in a slender cylinder constituted by a nonlinearly elastic material. Starting from the three-dimensional nonlinear field equations, we derive, through a novel method, a singular dynamical system as the normal form equation. It is shown that this system can capture the corner instabilities. We are also able to obtain analytical expressions of the solutions. The mechanism that causes corner formations is also found. To cite this article: H.-H. Dai, F.-F. Wang, C. R. Acad. Sci. Paris, Ser. I 345 (2007).