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Based on the theoretical definition of the quality of economic growth as well as the availability and reliability of the given data, the purpose of this paper is to build an evaluation system of a regional economic growth quality on three levels: conditions, processes and results.

From the perspective of economic quality, this paper offers a theoretical interpretation on how the urban–rural income gap affects the quality of economic growth and takes an empirical test on the sample panel data from 30 provinces and regions through difference GMM and system GMM models.

The results show that the excessively large income gap will influence economic growth in terms of the foundation, operation and the outcome, thereby, restricting the quality of economic growth. In addition, investments in human and physical capital and improvements in terms of transport infrastructure, industrial structure and economic openness play an active role in economic growth quality, whereas government expenditure scale, financial development and the deviation of industrial structure have a negative effect.

There has been a substantial amount of experience and evidence on the research about the issue of China’s income distribution and the quantity of economic growth, whereas there are relatively fewer discussions about the income distribution and the quality of economic growth. This paper, based on what has been mentioned above, tries to give a theoretical interpretation and an empirical test to describe the relationship between urban–rural income gap and the quality of economic growth from the quality point of view.

This work aims to demonstrate the vibration suppression of the rotor system with localized defects on bearing using an integral squeeze film damper (ISFD).

Experiments were carried out to study the vibration characteristics of the rotor system with ISFD mounted on fault deep groove ball bearings. Three fault bearings including bearing with outer race defect, inner race defect and ball defect have been used in this paper. The results were compared by use of vibration acceleration level, continuous wavelet transform and envelope spectrum.

It was found that ISFD shows excellent damping and vibration attenuation characteristics of the rotor system with defective bearing. The fault bearing rotor system with external ISFD considerably reduces the vibration energy and amplitude compared with the system without ISFD.

There is a dearth of experimental research pertaining to vibration characteristics of rotor system support by defective bearings with ISFD. Besides, the test provides evidence for the application of ISFD in vibration control of the rotor system with incipient defects on bearing.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0144/

Surface texturing has emerged in the past two decades as a viable option of surface engineering, resulting in significant improvement in wear resistance and friction coefficient. The purpose of this study is to find the appropriate surface texture to reduce vibration and improve the stability of journal bearings.

Micro-dimples, evenly distributed in a square array, were selected as the texture pattern and formed on the lower surface of bush by the laser surface texturing technique. Experiments were carried out to evaluate the effects of micro-dimples under different depths, densities and distributions.

The results are summarized in the form of shaft center orbits, waterfall illustrations and Hilbert-Huang transforms. In the entire test, it was found that an optimum geometric and distributive range of micro-dimples exists, where vibration acceleration can be decreased at least 3dB and stability can be greatly improved.

A majority of researchers devoted to studying on static characteristics, such as friction coefficient, load carrying capacity, pressure distribution and cavitation model. Besides, the influence of surface texture on stability of rotor-journal bearing system was rarely investigated and the recent examples can be found in Refs. (Ausas et al. 2007). However, a complete study of textured journal bearings has not been undertaken in the dynamic properties. Therefore, the purpose of this paper is to experimentally investigate the comprehensive effects of density, depth and distribution of micro-dimples on bearing vibration and stability.