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1 – 4 of 4Junshan Hu, Jie Jin, Yueya Wu, Shanyong Xuan and Wei Tian
Aircraft structures are mainly connected by riveting joints, whose quality and mechanical performance are directly determined by vertical accuracy of riveting holes. This paper…
Abstract
Purpose
Aircraft structures are mainly connected by riveting joints, whose quality and mechanical performance are directly determined by vertical accuracy of riveting holes. This paper proposed a combined vertical accuracy compensation method for drilling and riveting of aircraft panels with great variable curvatures.
Design/methodology/approach
The vertical accuracy compensation method combines online and offline compensation categories in a robot riveting and drilling system. The former category based on laser ranging is aimed to correct the vertical error between actual and theoretical riveting positions, and the latter based on model curvature is used to correct the vertical error caused by the approximate plane fitting in variable-curvature panels.
Findings
The vertical accuracy compensation method is applied in an automatic robot drilling and riveting system. The result reveals that the vertical accuracy error of drilling and riveting is within 0.4°, which meets the requirements of the vertical accuracy in aircraft assembly.
Originality/value
The proposed method is suitable for improving the vertical accuracy of drilling and riveting on panels or skins of aerospace products with great variable curvatures without introducing extra measuring sensors.
Details
Keywords
Junshan Hu, Xinyue Sun, Wei Tian, Shanyong Xuan, Yang Yan, Wang Changrui and Wenhe Liao
Aerospace assembly demands high drilling position accuracy for fastener holes. Hole position error correction is a key issue to meet the required hole position accuracy. This…
Abstract
Purpose
Aerospace assembly demands high drilling position accuracy for fastener holes. Hole position error correction is a key issue to meet the required hole position accuracy. This paper aims to propose a combined hole position error correction method to achieve high positioning accuracy.
Design/methodology/approach
The bilinear interpolation surface function based on the shape of the aerospace structure is capable of dealing with position error of non-gravity deformation. A gravity deformation model is developed based on mechanics theory to efficiently correct deformation error caused by gravity. Moreover, three solution strategies of the average, least-squares and genetic optimization algorithms are used to solve the coefficients in the gravity deformation model to further improve position accuracy and efficiency.
Findings
Experimental validation shows that the combined position error correction method proposed in this paper significantly reduces the position errors of fastener holes from 1.106 to 0.123 mm. The total position error is reduced by 43.49% compared with the traditional mechanics theory method.
Research limitations/implications
The position error correlation method could reach an accuracy of millimeter or submillimeter scale, which may not satisfy higher precision.
Practical implications
The proposed position error correction method has been integrated into the automatic drilling machine to ensure the drilling position accuracy.
Social implications
The proposed position error method could promote the wide application of automatic drilling and riveting machining system in aerospace industry.
Originality/value
A combined position error correction method and the complete roadmap for error compensation are proposed. The position accuracy of fastener holes is reduced stably below 0.2 mm, which can fulfill the requirements of aero-structural assembly.
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Xudong Zhuang and Junshan Duan
The purpose of this study is to evaluate the impact of environmental uncertainty on corporate social responsibility (CSR), and involves corporate financial investment as mediating…
Abstract
Purpose
The purpose of this study is to evaluate the impact of environmental uncertainty on corporate social responsibility (CSR), and involves corporate financial investment as mediating factor into this relationship to identify whether Chinese enterprises pursue fame or profit under rising environmental uncertainty.
Design/methodology/approach
Data of listed companies in China from 2010 to 2019 are employed. Fixed effect and mediating effect models were used to explore the relationship between environmental uncertainty, corporate financial investment, and CSR. The heterogeneity influence and moderating effect are discussed by using the method of grouping test and adding interactive items.
Findings
The study finds that rising environmental uncertainty has a negative impact on CSR. It stimulates managements' short-sighted motivation, so that enterprises prioritize financial investment that can solve short-term goals, rather than CSR performance. This inhibitory effect is caused by holding illiquid financial assets with the motivation of “speculative profit seeking.” The negative effect is greater in the samples of state-owned enterprises, nonfamily enterprises and enterprises with low risk-taking.
Practical implications
It provides a decision-making direction for implementation of CSR governance and the construction of CSR system, particularly in emerging market economies.
Social implications
CSR is widely known in developed countries for its formation, development and role, but its effectiveness and behavioral motivation are less mentioned in emerging markets. In the future, the research in this area needs to be further advanced.
Originality/value
The study makes significant contributions to the mechanisms behind the link between environmental uncertainty and CSR by taking corporate financial investment as an intermediary factor into the analysis, especially in the unique market context of China.
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With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the…
Abstract
Purpose
With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the social climate of China.
Design/methodology/approach
This study examines 97 severe corruption cases of high-ranking officials in China, which occurred between 2012 and 2015. As this insinuates that both institutional and social corruption are major problems in China, the analysis delves into multiple facts of corruption, including different types, four primary underlying causes, and suggestions regarding the implementation of three significant governmental shifts that focus on investigation, prevention tactics and legal regulations.
Findings
China’s corruption is not only individual-based but also it has developed into institutional corruption and social corruption. Besides human nature and instinct, the causes of corruption can be organised into four categories, namely, social customs, social transitions, institutional designs and institutional operations. For the removed high-ranking officials, the formation of interest chains was an important underlying cause behind their corruption.
Originality/value
This study makes a significant contribution to the literature because this study provides a well-rounded approach to a complex issue by highlighting the significance of democracy and the rule of law as ways to regulate human behaviour to combat future corruption.
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