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At present, the evaluation methodology on the design innovation of the stadia is not complete. The degree of innovation of the design scheme of the stadia still cannot be quantitatively estimated; this inability makes it difficult to guide the selection of a design scheme. To solve the problem of evaluation on the innovative design of the stadia, improve such design’s evaluation theory, and accurately direct the selection of the design scheme of the stadia, the Delphi method is used to select evaluation indexes. Moreover, analytic hierarchy process (AHP) is applied to determine the index weight in this study; based on this index weight, fuzzy comprehensive evaluation is used to establish the model of the design innovation evaluation of the stadia. The model involves the comprehensive and simple selection of indexes and the high reliability of weight selection; the model can quantitatively calculate the comprehensive index evaluation value of the design innovation of the stadia in a relatively accurate and rapid way. In this study, Hunan People’s Stadium is taken as the example for design innovation evaluation; the procedure of design innovation evaluation is introduced in detail. The design innovation evaluation value of the stadia is 2.977 through analysis; this value indicates an ordinary degree of innovation. The innovation evaluation value of the shape is 3.425; this value shows a relatively high degree of innovation. The innovation evaluation value of the structure is 2.47; this value represents a relatively low degree of innovation. The model in this study is an accurate and prompt model that can conduct a comprehensive evaluation on the design innovation of the stadia based on quantitative calculation. This model directly and comprehensively finds the advantages and disadvantages of a design scheme. Thus, it is quite suitable for the design innovation evaluation of the stadia.

This study aims to investigate mixed lubrication performances of stern bearing in a misaligned state considering turbulence and bearing deformation impacts.

A mixed lubrication model of stern bearing is established. The generalized average Reynolds equation governing the turbulent flow of lubricant is analyzed by considering the interaction of bearing elastic deformation, asperity contact pressure and film pressure. The bearing behaviors including minimum film thickness, hydrodynamic pressure, asperity friction force and frictional coefficient are studied under different models. The correctness of this model is verified by comparing it with that of the published data.

Numerical results indicate that elastic deformation noticeably decreases the maximum film pressure, the asperity contact force and the friction coefficient in the mixed lubrication stage. The effect of elastic deformation and turbulence reduces the transition speed from mixed to liquid lubrication.

This model includes both turbulence and bearing deformation impacts on journal bearing performances. It is expected that the numerical results can provide useful information to establish a stern bearing exposed to mixed lubrication conditions.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2022-0352/

The purpose of this paper is to investigate the friction and wear mechanisms in copper-based self-lubricating composites with MoS₂ as the lubricating phase, which provides a theoretical basis for subsequent research on high-performance copper-based self-lubricating materials.

Friction tests were performed at a speed of 100 r/min, a load of 10 N, a friction radius of 5 mm and a sliding speed of 30 min. Friction experiments were carried out at RT-500°C. The phase composition of the samples was characterized by X-ray diffraction of Cu Ka radiation, and the microstructure, morphology and elemental distribution were characterized by scanning electron microscopy and energy dispersive spectroscopy. Reactants and valences formed during the wear process were analyzed by X-ray photoelectron spectroscopy.

The addition of MoS₂ can effectively improve friction-reducing and anti-wear action of the matrix, which is beneficial to form a lubricating film on the sliding track. After analyzing different changing mechanism of the sliding tracks, the oxides and sulfides of MoS₂, MoO₂, Cu₂O, CuO and Ni(OH)₂ were detected to form a synergetic lubricating film on the sliding track, which is responsible for the excellent tribological properties from room to elevated temperature.

For self-lubrication Cu–Sn–Ni–MoS₂ material in engineering field, there are still few available references on high-temperature application.

This paper provides a theoretical basis for the following research on copper-based self-lubricating materials with high performance.

With this statement, the authors hereby certify that the manuscript is the results of their own effort and ability. They have indicated all quotes, citations and references. Furthermore, the authors have not submitted any essay, paper or thesis with similar content elsewhere. No conflict of interest exits in the submission of this manuscript.

Micro-texture is processed on the surface to reduce the friction of the contact surface, and its application is more and more extensive. The purpose of this paper is to create a texture function model to study the influence of surface parameters on the accuracy of the simulated surface so that it can more accurately reflect the characteristics of the real micro-textured surface.

The microstructure function model of rough surfaces is established based on fractal geometry and polar coordinate theory. The offset angle θ is introduced into the fractal geometry function to make the surface asperity normal perpendicular to the tangent of the surface. The 2D and 3D contour surfaces of the surface groove texture are analyzed by MATLAB simulation. The effects of fractal parameters (D and G) and texture parameter h on the curvature of the surface micro-texture model were studied.

This paper more accurately characterizes the textured 3D curved surface, especially the surface curvature. The scale coefficient G significantly affects curvature, and the influence of fractal dimension D and texture parameters on curvature can be ignored.

The micro-texture model of the rough surface was successfully established, and the range of fractal parameters was determined. It provides a new method for the study of surface micro-texture tribology.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2023-0298/

Ant colony algorithm is widely used in recent years as a heuristic algorithm. It provides a new way to solve complicated combinatorial optimization problems. Having been enlightened by the behavior of ant colony's searching for food, positive feedback construction and distributed computing combined with certain heuristics are adopted in the algorithm, which makes it easier to find better solution. This paper introduces a series of ant colony algorithm and its improved algorithm of the basic principle, and discusses the ant colony algorithm application situation. Finally, several problems existing in the research and the development prospect of ACO are reviewed.

The purpose of this paper is to examine the emerging Chinese credit rating agencies (CRAs), and their development, regulatory regime and challenges. The Chinese financial system has made many improvements; in particular, the regulatory regime has reached a more effective level. However, it should be admitted that some aspects still require further development. Compared with other developed markets, the Chinese credit rating industry is still young. Under these circumstances, questions are raised about the performance of the CRAs in China. Whether the legal framework is effective enough? A further point, in terms of the development, is what are the major obstacles lying ahead for the Chinese CRAs?

This paper will concentrate on the study of Chinese CRAs. Starting with a brief introduction and analysis on the Chinese CRAs, it will further examine the rating methodologies of the Chinese CRAs. Following this, the regulatory regimes will be analyzed in detail, from the perspectives of the securities, banking and insurance market. Moreover, the paper will identify the key problems under the current regulatory regime. Last but not least, a conclusion and some future suggestions for the development of the regulatory regime will also be made based on the earlier observations and study.

The current development stage and future reform requirement of the Chinese credit rating industry.

Provide a full dimension and in depth analysis on the Chinese credit rating industry.