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The electromechanical planetary transmission system has the advantages of high transmission power and fast running speed, which is one of the important development directions in the future. However, during the operation of the electromechanical planetary transmission system, friction and other factors will lead to an increase in gear temperature and thermal deformation, which will affect the transmission performance of the system, and it is of great significance to study the influence of the temperature effect on the nonlinear dynamics of the electromechanical planetary system.

The effects of temperature change, motor speed, time-varying meshing stiffness, meshing damping ratio and error amplitude on the nonlinear dynamic characteristics of electromechanical planetary systems are studied by using bifurcation diagrams, time-domain diagrams, phase diagrams, Poincaré cross-sectional diagrams, spectra, etc.

The results show that when the temperature rise is less than 70 °C, the system will exhibit chaotic motion. When the motor speed is greater than 900r/min, the system enters a chaotic state. The changes in time-varying meshing stiffness, meshing damping ratio, and error amplitude will also make the system exhibit abundant bifurcation characteristics.

Based on the principle of thermal deformation, taking into account the temperature effect and nonlinear parameters, including time-varying meshing stiffness and tooth side clearance as well as comprehensive errors, a dynamic model of the electromechanical planetary gear system was established.

A dynamic model of the brake system considering the tangential and radial motion of the pad, and the torsion and wobbling motion of the disk is established in this paper. The influence of radial stiffness on the brake system is investigated under different tribological conditions. This paper aims to prove that sufficient radial stiffness is indispensable in the design of the brake system with good tribological performance.

By using the lumped mass method, a dynamic model of the brake system is established. A Stribeck-type friction model is applied to this model to correlate the frictional velocity, pressure and friction force. The stability of pad vibration is analysed by analysis methods. A new stability evaluation parameter is proposed to study the influence of radial stiffness on stability of pad vibration in a certain friction coefficient brake pressure range.

The findings show that the tangential vibration of the pad transits from periodic motion to quasi-periodic motion under a low tangential stiffness. The influence of radial stiffness on motion stability is stronger under a low nominal brake radius. The stability of the brake system can be ensured when the brake radius and radial stiffness are sufficient.

The influence of tangential stiffness of pad on stability of the brake system has been researched for decades. The insufficiency of stiffness in radial direction may also generate certain levels of instabilities but has not been fully investigated by modelling approach. This paper reveals that this parameter is also strongly correlated to nonlinear vibration of the brake pad.

World legends and the scientific community have taken the devastating impact of poverty issue seriously which has been reflected in the growing trend of research in this area. Hence, this paper aims to conduct a bibliometric analysis on poverty alleviation literature, discuss the various dimensions of poverty alleviation and deliver some ideas for future research.

This study deploys a combined quali-quantitative method familiar as meta-literature review on 454 articles collected from the Web of Science (WoS) database with Social Science Citation Index (SSCI) coverage over the period 1971–2020. Using Rstudio, VOSviewer and Excel, the collected data have been analysed from different lenses.

This study considers the most contributing scientific actors like authors, journals, topics, institutions and countries as parameters for analysing articles. Based on the analysis from various perspectives, it determines five main research streams upon which it provides some potential research directions to be considered in future research.

This study solely relies on the articles available in the WoS database with index in SSCI. However, it excludes analysing thousands of articles on the same topic available in other platforms.

This study provides a retrospective on the scientific works and collective efforts of scholars germane to poverty alleviation from the highest ranked journals, which would help better understand the literature development and the intellectual structure of this field.