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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.

Supernumerary robotic limbs (SRLs) are a new type of wearable robot, which improve the user’s operating and perceive the user’s environment by extra robotic limbs. There are some literature reviews about the SRLs’ key technology and development trend, but the design of SRLs has not been fully discussed and summarized. This paper aims to focus on the design of SRLs and provides a comprehensive review of the ontological structure design of SRLs.

In this paper, the related literature of SRLs is summarized and analyzed by VOSviewer. The structural features of different types of SRLs are extracted, and then discuss the design approach and characteristics of SRLs which are different from typical wearable robots.

The design concept of SRLs is different from the conventional wearable robots. SRLs have various reconfiguration and installed positions, and it will influence the safety and cooperativeness performance of SRLs.

This paper focuses on discussing the structural design of SRLs by literature review, and this review will help researchers understand the structural features of SRLs and key points of the ontological design of SRLs, which can be used as a reference for designing SRLs.

Sustainable development requires companies to achieve a long-term balance between the economic, environmental and social spheres in their development process, and is not limited to long-term commercial success. Enhancing corporate environmental, social and governance (ESG) performance plays a critical role in achieving sustainable economic and social development. The purpose of this study is to empirically examine the influence of short-selling on corporate ESG performance and unravel the mechanisms involved.

The authors use the data from Chinese A-share listed companies spanning from 2010 to 2021 as the research sample and conduct empirical research using mediating effect model, instrumental variables and difference-in-differences methods.

The findings suggest that short-selling has a positive impact on ESG performance, thus, contributing to the realization of sustainable development goals (SDGs) and achieving a balanced development of economy, environment and society, rather than only promoting corporate longevity. This can be attributed to short-selling’s ability to strengthen supervision constraints on firms, improve firms’ intrinsic capabilities and promote firms’ green technological innovation. Furthermore, the ESG-enhancing effects of short-selling are contingent upon the internal and external governance levels of the firms. That is, short-selling has a more significant effect on ESG performance enhancement for firms with weaker internal and external governance. The extended analysis finds that concerning firms’ market advantage, the positive impact of short-selling on ESG is more pronounced for firms with weak monopoly power and those facing intense industry competition. In addition, when examining firms’ individual characteristics, the ESG-enhancing effect of short-selling is more potent for nonstate-owned firms, those with a shorter listing history and those facing a heightened risk of resource mismatch.

This study provides theoretical support and empirical evidence from the perspective of short-selling to help boost corporate ESG development and improve corporate contributions to sustainable development. ESG is the concrete projection of sustainable development concept at the firm level. Good ESG performance contributes to the realization of the SDGs by influencing the strategy, operation and management of the enterprise, and promoting the enterprise to more actively create the comprehensive value of the economy, society and environment.

The results of this study show that short-selling can significantly enhance corporate ESG performance and strengthen corporate sustainability initiatives, thereby promoting the realization of SDGs at the firm level. These findings carry substantial implications, not only foster the improvement of China’s capital market system but also provide empirical evidence from China for capital market policy-making and sustainable development practices in other emerging markets.

This study not only addresses the gap in studying ESG performance from the perspective of short-selling behavior but also enriches the research on the economic consequences of short-selling and enriches the literature on the determinants of ESG performance.

The aim of this study is to first investigate the surface integrity of cylindrical rollers under grinding process and then design a reasonable superfinishing process that improve the anti-fatigue performance of cylindrical rollers by optimization of the surface integrity.

First, the white and dark layers produced by the grinding process is analyzed by microscope. Then, the influence of oilstone pressure on the stock removal, surface precision and crowned profile are explored. Finally, an optimal superfinishing process and a novel turnaround device are designed to improve surface integrity.

The experimental results show that as the oilstone pressure increases, the stock removal first increases and then remains stable. This hints that the stock removal of a single-time superfinishing process has an upper limit. In the current conditions, the maximum stock removal is 6 µm. Double-time superfinishing process and the turnover device can effectively eliminate the white and dark layers and improve the symmetric of roller profile. In addition, the surface precision is also improved.

The surface integrity of bearing rollers is very important to the application of industry field. The findings and the methods in the study can be helpful to improve the surface integrity of the bearing rollers.

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 green building (GB) maintenance industry has been under increasing pressure by designers to demonstrate its evaluation and information management of building information modelling based model checking (BMC) to the competency's performance and design knowledge of building control instrument. This main problem has been termed as maintenance planning level. Although maintenance planning has been explored in GB maintenance environments, less is known about what maintenance planning problems currently exist and what their causes are, such as the recent fire in the Grenfell Tower (14 June 2017, about 80 fatalities) in North Kensington, West London. The aim of this paper is to identify how GB maintenance environments could integrate BMC within their processes. The purpose of this study is to assess the BMC technology management of GB maintenance ecosystem and that of a soft skills level to establish the impact of innovation policy features on database and safety risk function mechanism.

To achieve this aim, a comprehensive literature review of the existing conceptualisation of BMC practices is reviewed and the main features of Information and Communication Technology tools and techniques currently being employed on such GB maintenance ecosystem is carried out to evaluate the strengths and weaknesses of the previous studies. The conceptual framework explores the importance of integration of BMC in the construction phase to identify alternative methods in the automation system (AS) process to co-generate, monitor and optimise BMC.

The results confirm that BMC tool positively influences database application and risk mechanism of construction project safety while agreeableness negatively does. Besides, database application has a negative influence on innovation policy of company towards BMC implementation. Propositions derived not only shed light on guidance for future research on the soft skills of construction organisations, but also provide decision-making support through a better understanding of the factors affecting soft skills level amongst biggest construction companies.

Thus far, this study advances the knowledge about how GB maintenance environments can ensure BMC delivery. This paper highlights the need for further research to integrate BMC in GB maintenance environments validates the framework across the construction phase with different GB project managers and engineers.

Green building (GB) maintenance is increasingly accepted in the construction industry, so it can now be interpreted as an industry best practice for maintenance planning. However, the performance competency and design knowledge of the practice's building control instrument process can be affected by its evaluation and the information management of building information modelling (BIM)–based model checking (BMC). These maintenance-planning problems have not yet been investigated in instances such as the Grenfell Tower fire (14 June 2017, approximately 80 fatalities) in North Kensington, West London.

This study proposes a theoretical framework for analysing the existing conceptualisation of BIM tools and techniques based on a critical review of GB maintenance environments. These are currently employed on GB maintenance ecosystems embedded in project teams that can affect BMC practices in the automation system process. In order to better understand how BMC is implemented in GB ecosystem projects, a quantitative case study is conducted in the Malaysian public works department (Jabatan Kerja Raya (JKR)).

GB ecosystem projects were not as effective as planned due to safety awareness, design planning, inadequate track insulation, environmental (in) compatibility and inadequate building access management. Descriptive statistics and an ANOVA were applied to analyse the data. The study is reinforced by a process flow, which is transformed into a theoretical framework.

Industry practitioners can use the developed framework to diagnose BMC application issues and leverage the staff competency inherent in an ecosystem to plan GB maintenance environments successfully.

When handling small-sized shafts and holes, achieving optimal safety, size compatibility and shape adaptability using rigid grippers presents significant problems. Recent advancements have introduced soft end-effectors that offer enhanced safety and adaptability for gripping parts. However, these soft end-effectors often struggle to maintain the necessary gripping positional accuracy. The purpose of this paper is to design a soft end-effector specifically engineered to address these problems, combining precise gripping capabilities with improved safety, positional accuracy and adaptability to the size and shape of fragile, small-sized components.

A soft finger with multilayer decreasing drive air chambers is designed to achieve the finger bending increasing from the root to the tip of the finger to improve the flexibility of the fingertip. Additionally, a three-finger self-centering configuration is employed, coupled with an expandable structure to increase the gripping range. Furthermore, a theoretical mathematical model of the finger is established. The physical prototype is manufactured and subjected to experimental testing, including gripping tests on small-sized, fragile shaft holes, to validate its operational performance.

The grasping experiments confirm that the designed end-effector can maintain coaxial positioning and meet adaptability requirements when handling fragile components with small-sized shaft holes. Furthermore, the addition of expanding palm structure increases the gripping attitude and enriches the application scene and gripping space.

The design of multilayer decreasing air chamber structure to solve the problem of poor gripping stability and low positional accuracy of soft manipulator; the expandable palm design is introduced to enhance gripping space; and solved the problem of gripping accuracy in the assembly of fragile parts with small-size shafts and holes.