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The analysis of the aerodynamic interference of the downwash on wings under different intensities on both sides of the rotor of the composite high-speed helicopter, can provide a certain reference for the design and optimization of the aerodynamic shape of the similar configuration helicopter.The unsteady momentum source method is used to perform the numerical simulation of the flow field of a composite high-speed helicopter in hovering and forward flight states, and the aerodynamic effects of different downwash on both sides of the rotor on wings are analyzed.The effect of aerodynamic characteristics on changing the height of the rotor disc and the aspect ratio of wing is studied.The results show that, when the composite high-speed helicopter flies forward, the peak lift difference between the two sides of the wing is decreased with the increase of the rotor disc height, and the peak value falls at a lower speed.With the increase of the wing aspect ratio, the peak lift difference between the two sides is decreased.Under the condition of same speed after the peak value, the slender the wing is, the smaller the lift difference between the two sides is.

Corporate environmental responsibilities have expanded to include their supply chains. Green supply chain management (GSCM) practices can be extensive – including both intra- and inter-organisational environmental management practices. Selecting and sequencing GSCM practices is an important issue given resource and strategic organisational considerations. Using the cumulative capabilities theory, this study empirically explores GSCM implementation sequences, following which firms can build cumulative capabilities. Correlation, sequential test, and path analysis are used to identify GSCM practice implementation sequence from secondary data. The results show that firms should first encourage suppliers to disclose their environmental data and respond to inquiries on environmental violations by their suppliers (the order of the two is exchangeable), then encourage suppliers to comply with environmental regulations, extend practices to lower-tier suppliers, and engage in responsible recycling. This study is one of the first to apply cumulative capability theory to analyse environmental practices and provides a framework for future research on GSCM sequences. The paper also offers practical implications for firms to adjust their strategies in order to adopt GSCM more effectively and successfully. [ABSTRACT FROM AUTHOR]

Leading manufacturers have struggled to extend their green supply chain management (GSCM) efforts to low-tier (the second- and even lower-tier) suppliers, but how to motivate low-tier suppliers to be involved is still a big challenge. This paper develops a low-tier GSCM model for managing second-tier suppliers. Based on stakeholder theory and literature review, this paper develops 25 drivers for the ìnvolvement of second-tier suppliers in low-tier GSCM by a manufacturer. Using data collected from 29 second-tier suppliers of a leading automobile manufacturer, this study identified 17 critical drivers. The Grey-DEMATEL method was used to examine the cause-effect relationships to reveal prominent and elemental drivers. Based on the evaluation by managers from the manufacturer, one first-tier supplier, and six second-tier suppliers, comparative analysis of the DEMATEL results show that the manufacturer understands the prominent role of second-tier suppliers for its low-tier GSCM implementation while second-tier suppliers know little about the manufacturer's requirements and the first-tier supplier ignores the importance of internal drivers by second-tier suppliers. In the long term, the manufacturer considers itself as the crucial firm for low-tier GSCM, but according to first- and second-tier suppliers, promoting policies by the government such as GSCM-related demonstration projects are also elemental. This study provides directions for multi-tier GSCM studies on the theoretical development about how to effectively involve second-tier suppliers by unveiling the difference in the understanding of drivers among firms along supply chains. [ABSTRACT FROM AUTHOR]