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It is very important to create a useful cyclic symmetric model for the investigation of the vibration reduction effect of hard-coating blisk. This study aims to develop a cyclic symmetry algorithm which can determine the mode of blisk in the sector coordinate system directly.

Using the exponential and real quasi-equivalent Fourier matrices, the formulas for solving the sector mode were derived, and the relationship between the two kinds of sector modes was also discussed. Based on the proposed cyclic symmetry algorithm, the vibration characteristics of an academic blisk were solved, and the formulas for solving the natural characteristics and vibration responses of the coated blisk were given.

A blisk with NiCrAlCoY+YSZ hard coating on both sides of each blade was chosen as a case to demonstrate the presented method. Based on the verification analysis model, the influences of coating thickness on the vibration reduction effect of the blisk were discussed. The results show that the hard coating has good vibration reduction effect on the blisk even the coating thickness is very thin and the vibration reduction effect of hard coating in the high frequency range is obviously better than that in the low frequency range.

As a large number of reduced order modeling methods of blisk are implemented based on the sector modes, the proposed method which can obtain the sector modes directly will significantly improve the efficiency of dynamic modeling and analysis of the coated blisk structure.

The purpose of this paper is to evaluate the effect of film cooling holes on the vibration characteristics of a turbine blade, and provide the design basis for the blade, which may reduce computing costs.

Modal analysis of the blades with and without film cooling holes is performed to evaluate the effect of film cooling holes on its natural frequency. Harmonic analysis of the blade is performed to calculate the stress concentration factors of film cooling holes for different modes.

The frequency differences between two blades with and without film cooling holes are insignificant, while the differences of the vibration stress cannot be neglected. For the first three modes of the blades, the stress concentration factor is sensitive to the hole’s shape and position on the blade. With the help of the stress concentration factor defined in this work, the concentration of stresses induced by different film cooling holes can be accurately described when evaluating HCF life of the turbine blade.

The effect of film cooling holes on a turbine blade's natural frequencies was confirmed to be insignificant and the stress concentration factors around the holes are calculated. Therefore, the simplified model of the blade without film cooling holes can be used to evaluate the natural frequencies and vibration stress, which saves a lot of time and cost.

Servitization has been used widely by manufacturing firms to secure strategic positions in industrial transformation. However, its impact on firms’ market power remains to be investigated, especially in developing countries. This study aims to investigate servitization’s impact on firms’ market power, along with the moderating roles of research and development (R&D) intensity and firm size.

Using the two-stage least squares with instrumental variables (2SLS-IV) method, the authors conduct an empirical analysis of servitization in China based on panel data for 1,797 publicly traded manufacturing firms during the period 2012–2018.

The findings show that servitization helps increase a firm’s market power. Furthermore, heterogeneity analysis suggests that embedded servitization increases a firm’s market power, whereas hybrid servitization reduces it. The findings also indicate that this effect varies depending on critical firm conditions. Servitization’s effect on firms’ market power increases with R&D intensity but decreases with manufacturer expansion.

This study describes the positive effects of servitization on firms’ market power in response to calls for research that will adopt a comprehensive business performance perspective on the servitization field.

The findings provide guidance for what type of servitization manufacturing firms should choose and how it fits with their size and R&D capabilities.

This pioneering empirical study uses a large longitudinal data set and the 2SLS-IV method to examine the effects of embedded servitization and hybrid servitization on firms’ market power. The findings provide a new perspective on ongoing discussions of “desertification” and the “service paradox.”