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Investigating the characteristics of the transformation of China's agricultural growth and the institutional reforms during the whole transition period in the 1980s will help to understand China's economic and agricultural reform and offer some successful experiences to other developing countries. The purpose of this paper is to answer the following questions: Has China's agricultural output experienced a structural break toward a more stable state? When did the break point happen? What factors did play key roles during the transformation?

This study applies the nonlinear structural break regime switching analysis which includes two different models: one with the structural break only in the variance and one with the structural break in both shift parameters and the variance.

The empirical results showed that it took five years for agricultural development in China to finish the reform that began in 1980. The agricultural growth had become more stable after the break point which was around 1985‐1986. Both the primary industry and agricultural sector had transformed from a “low growth rate, high volatility” state to a “high growth rate, low volatility” state. Among the different driving factors, the Household Responsibility System (HRS) and preferential policies for agricultural products played the most important roles in the early stage of the economic reform.

The authors first study the structural break of China's agricultural output by the regime switching model. From the empirical results, the structural break point was determined to be around 1985‐1986, after which China's agricultural output had become more stable.

This paper aims to present the mechanical design and kinematics of a novel rigid-flexible coupling hybrid robot to develop a promising aeroengine blades in situ repair technology.

According to requirements analysis, a novel rigid-flexible coupling hybrid robot is proposed by combining a three degrees of freedom (DOF) parallel mechanism with a flexible continuum section. Then the kinematics models of both parallel mechanism and flexible continuum section are derived respectively. Finally, based on equivalent joint method, a two-step numerical iterative inverse kinematics algorithm is proposed for the whole robot: (1) the flexible continuum section is equivalently transformed to a 2-DOF spherical joint, thus the approximate analytical inverse kinematic solution can be obtained; (2) the accurate solution is derived by an iterative derivation of both parallel mechanism and flexible continuum section.

To verify structure scheme and the proposed kinematics modeling method, numerical simulations and prototype experiments are implemented. The results show that the proposed kinematics algorithm has sufficient accuracy and computational efficiency in the whole available workspace, that is end-effector position error and orientation error are less than 0.2 mm and 0.01° respectively, and computation time is less than 0.22s.

A novel rigid-flexible coupling hybrid robot for aeroengine blades in situ repair is designed. A two-step numerical iterative inverse kinematics algorithm is proposed for this unique hybrid robots, which has good accuracy and computational efficiency.