With the deepening of economic globalization and increasingly fierce competition of trade liberalization in WTO member countries,the effect of traditional trade protection measures is gradually weakening or even remov...With the deepening of economic globalization and increasingly fierce competition of trade liberalization in WTO member countries,the effect of traditional trade protection measures is gradually weakening or even removed. In recent years,Technical Barriers to Trade( TBT)as a category of nontariff barriers to trade,are the widely divergent measures that countries use to regulate markets,protect their consumers,or preserve their natural resources( among other objectives),but they also can be used( or perceived by foreign countries) to discriminate against imports in order to protect domestic industries. These directly or indirectly lead to gradual rise of trade friction of China's pork export. This paper analyzed background and significance of measures for TBT of pork export,current situations of researches on TBT both at home and abroad,and came up with new ideas and viewpoints for further strengthening measures for TBT of pork export.展开更多
The authors investigate the trajectory tracking control problem of an upper limb reha-bilitation robot system with unknown dynamics.To address the system's uncertainties and improve the tracking accuracy of the re...The authors investigate the trajectory tracking control problem of an upper limb reha-bilitation robot system with unknown dynamics.To address the system's uncertainties and improve the tracking accuracy of the rehabilitation robot,an adaptive neural full-state feedback control is proposed.The neural network is utilised to approximate the dy-namics that are not fully modelled and adapt to the interaction between the upper limb rehabilitation robot and the patient.By incorporating a high-gain observer,unmeasurable state information is integrated into the output feedback control.Taking into consider-ation the issue of joint position constraints during the actual rehabilitation training process,an adaptive neural full-state and output feedback control scheme with output constraint is further designed.From the perspective of safety in human–robot interaction during rehabilitation training,log-type barrier Lyapunov function is introduced in the output constraint controller to ensure that the output remains within the predefined constraint region.The stability of the closed-loop system is proved by Lyapunov stability theory.The effectiveness of the proposed control scheme is validated by applying it to an upper limb rehabilitation robot through simulations.展开更多
基金Supported by Science and Technology Program Project of General Administration of Quality Supervision,Inspection and Quarantine of the People's Republic of China(2014IK242)Science and Technology Planning Project of Sichuan Province(2014ZR0118)Key Science and Technology Self-Funded Project of Sichuan Province in 2013(2013ZRZ008)
文摘With the deepening of economic globalization and increasingly fierce competition of trade liberalization in WTO member countries,the effect of traditional trade protection measures is gradually weakening or even removed. In recent years,Technical Barriers to Trade( TBT)as a category of nontariff barriers to trade,are the widely divergent measures that countries use to regulate markets,protect their consumers,or preserve their natural resources( among other objectives),but they also can be used( or perceived by foreign countries) to discriminate against imports in order to protect domestic industries. These directly or indirectly lead to gradual rise of trade friction of China's pork export. This paper analyzed background and significance of measures for TBT of pork export,current situations of researches on TBT both at home and abroad,and came up with new ideas and viewpoints for further strengthening measures for TBT of pork export.
基金National Natural Science Foundation of China,Grant/Award Numbers:61563032,61963025Science and Technology Program of Gansu Province,Grant/Award Numbers:22CX8GA131,22YF7GA164。
文摘The authors investigate the trajectory tracking control problem of an upper limb reha-bilitation robot system with unknown dynamics.To address the system's uncertainties and improve the tracking accuracy of the rehabilitation robot,an adaptive neural full-state feedback control is proposed.The neural network is utilised to approximate the dy-namics that are not fully modelled and adapt to the interaction between the upper limb rehabilitation robot and the patient.By incorporating a high-gain observer,unmeasurable state information is integrated into the output feedback control.Taking into consider-ation the issue of joint position constraints during the actual rehabilitation training process,an adaptive neural full-state and output feedback control scheme with output constraint is further designed.From the perspective of safety in human–robot interaction during rehabilitation training,log-type barrier Lyapunov function is introduced in the output constraint controller to ensure that the output remains within the predefined constraint region.The stability of the closed-loop system is proved by Lyapunov stability theory.The effectiveness of the proposed control scheme is validated by applying it to an upper limb rehabilitation robot through simulations.
