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Accumulative evidence has shown that Tai Chi Chuan has significant rehabilitative effects in the elderly and in those with chronic diseases. Based on different movement patterns, the individual stances of Tai Chi Chuan require different integrated abilities and also meet the needs of different rehabilitation goals. However, there is still lack of efficient means of collecting rehabilitation related data and accurate methods of assessing the quality of Tai Chi Chuan movements. Establishing specifications for data collection and assessment techniques for the Tai Chi Chuan movements can help to quantify the relevant research work. Uniform standards enable better integration and sharing of Tai Chi Chuan movements data. It can help to find the link between rehabilitation status and Tai Chi Chuan movements data more accurately, allowing better application of Tai Chi Chuan in rehabilitation training.Therefore, this standard regulates the terms and definitions of data collection for Tai Chi Chuan, techniques of data collection and assessment, facilities and equipment, personnel requirements, sites and environmental requirements,as well as assessment precautions for Tai Chi Chuan movements. This standard is applicable to rehabilitation related data collection and assessment of rehabilitation function for Tai Chi Chuan movements, with good feasibility, and safety.

Promoting charge storage and fast charging capability simultaneously is a long–standing challenge for supercapacitors. A facile flowing seed polymerization is adopted to prepare polyaniline (PANI) nanofibers, in which phytic acid (PA) doped oligomers are first produced as the seeds for promoting the highly oriented growth of PANI nanofibers accompanying with the copolymerization of m−aminobenzene sulfonic acid (ASA) and aniline occurred on the surface of PANI nanofibers, as a result, unique core−shell structured PANI nanofibers are continuously fabricated. Benefitting from compact nanofiber structure, excellent dispersion, and self–doping effect, as–prepared PANI nanofibers exhibit a specific capacitance of 671.2 F g−1 at 2 A g−1 and ultrahigh rate capability of 93.1% from 2 to 100 A g−1. Then assembled all–solid–state supercapacitor can deliver the highest energy density of 28.3 Wh kg−1 at a power density of 320.2 W kg−1 with remarkable rate capability (81.2% from 1 to 20 A g−1), cycle stability (77.5% after 5000 cycles) as well as light weight and flexibility. It is highly desirable that the present green and scalable approach can be further applied to fabricate other unique core–shell structured PANI nanofibers with appealing potentials in energy storage devices. [ABSTRACT FROM AUTHOR]

This paper introduces a trapezoidal orthogonal stiffener steel plate shear wall (TSW). The finite element model of the TSW was developed following the validation of low-cycle repeated tests conducted on a single-span double-layer steel plate shear wall. The paper studies the effects of the flat steel plate thickness, stiffener thickness, stiffener height, and stiffener bottom width on the seismic performance of TSW. Building upon these findings, a theoretical formula for the ultimate shear capacity of TSW was developed. The results prove the following: (1) By changing the flat steel plate thickness, the stiffener thickness, and the stiffener height, the seismic behavior of TSW can be enhanced. It is suggested that the flat steel plate thickness is 4~6 mm, the stiffener thickness is 4~6 mm, and the stiffener height is not more than 60 mm, while the effect of the stiffener bottom width on the seismic behavior of TSW can be neglected. (2) The maximum error is 22.16%, compared to the theoretical value of TSW ultimate shear capacity with the finite element simulation value. However, as the finite element results surpass the test results, it indicates that the formula-derived results are unsafe, necessitating a recommendation for correction. [ABSTRACT FROM AUTHOR]

Considering the dynamics model parameter uncertainty and external disturbance of four-wheeled omnidirectional mobile robot,a kind of four- wheeled omnidirectional mobile robot trajectory tracking control method based on adaptive sliding mode is put forward in order to improve the trajectory tracking control performance. Firstly,the robot dynamics model is established on the basis of drive motor parameters. And an adaptive sliding mode trajectory tracking controller is designed. At the same time a parameter adaptive control algorithm is proposed in order to achieve the online estimation of the robot dynamics parameters,and real- time switch gain adjustment of trajectory tracking controller is achieved by using RBF neural network as to reduce the chattering of the system. Finally,the simulation experiment is carried out by using MATLAB in order to verify the effectiveness of the described method. The simulation results show that the four- wheeled omnidirectional mobile robot trajectory tracking method based on adaptive sliding mode control can well reduce the effects of parameter variations and external disturbances on the system. It can reduce the chattering of the system and has good anti- interference ability.

Having easy control of the morphology and structure as well as large-scale production, seed polymerization has exhibited great potential to fabricate polyaniline (PANI) nanofibers as high-performance electrode materials for the supercapacitors. Herein the self-assembly of oligomer seeds was first constructed by chemical oxidation of aniline in a dilution solution by regulating the acidity and especially the nature of inorganic acids including hydrochloric acid (HCl), sulfuric acid (H2SO4), and phosphoric acid (H3PO4), and then the successive growth of PANI nanofibers was carried out at high aniline concentration in a HCl solution. It was found that the charge-storage ability of PANI nanofibers can be greatly affected by the nanofibrous morphology and chain orientation that are more strongly related to the self-assembly behavior of nanofibrous oligomers as the seeds. It is found that the nature and acidity of inorganic acids have only a slight influence on the morphology, but a significant change occurred in the structure of the resulting PANI nanofibers. Especially, the nanofibers prepared by using the seeds in a HCl solution with a pH value of 3 possess a maximum specific capacitance of 504 F·g–1 at a current density of 1 A·g–1, holding a capacitance retention value of 90% within the range of the current density from 1 to 10 A·g–1. Furthermore, the symmetric supercapacitor with a sandwich structure was assembled that could deliver a maximum energy density of 17.8 Wh·kg–1 at a power density of 416.1 W·kg–1, accompanied by a capacitance retention value of 70.2% after 2000 cycles. Small-diameter and highly oriented chains as well as high conductivity are in favor of fast penetration of an electrolyte and ion diffusion along with a shortening of the charge-transfer distance, which could contribute to the strong charge-storage ability of PANI nanofibers. [ABSTRACT FROM AUTHOR]