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This study aims to investigate the impact of institutional fragility on the innovation investments of enterprises by analyzing the moderating effect of government subsidies and the integration of industry and finance.

Multiple regression analysis was used on 10,838 samples of 2,356 listed companies in China for the period 2007–2017, to empirically test the influence of institutional fragility on innovation investment. Moreover, Heckman’s two-stage approach was used for the robustness of the regression results.

The results show that the relationship between institutional fragility and innovation investment is an inverted U-shaped; government subsidies negatively moderate the relationship between institutional fragility and innovation investment, while the integration of industry and finance positively moderates them. Further analysis shows that the relationship between institutional fragility and innovation investment is more significant for high-tech enterprises. Similarly, the relationship between institutional fragility and innovation output also presents an inverted U-shape, which mainly affects enterprises’ breakthrough innovation output, but has no substantial impact on the incremental innovation output.

The conclusions provide new ideas for guiding the government’s reform, promoting the integration of industry and finance and promoting enterprise innovation.

The purpose of this paper is to develop a build strategy for inclined thin-walled parts by exploiting the inherent overhanging capability of the cold metal transfer (CMT) process, which release wire-arc additive manufacturing from tedious programming work and restriction of producible size of parts.

Inclined thin-walled parts were fabricated with vertically placed welding torch free from any auxiliary equipment. The inclined features were defined and analyzed based on the geometrical model of inclined parts. A statistical prediction model was developed to describe the dependence of inclined geometrical features on process variables. Based on these models, a build strategy was proposed to plan tool path and output process parameters. After that, the flow work was illustrated by fabricating a vase part.

The formation mechanism and regulation of inclined geometrical features were revealed by conducting experimental trials. The inclined angle can be significantly increased along with the travel speed and offset distance, whereas the wall width is mainly dependent on the ratio of wire feed speed to travel speed. In contrast to other welding process, CMT has a stronger overhanging capability, which provides the possibility to fabricate parts with large overhanging features directly with high forming accuracy.

This paper describes a novel build strategy for inclined thin-walled parts free from any auxiliary equipment. With the proposed strategy, a complex structural component can be deposited directly in the rectangular coordinates additive manufacturing system, indicating infinite possibilities on the producible size of the parts. Moreover, equipment requirements and tedious program work can also be significantly reduced.

The buried pipe element method can be used to calculate the temperature of mass concrete through highly efficient computing. However, in this method, temperatures along cooling pipes and the convection coefficient of the cooling pipe boundary should be improved to achieve higher accuracy. Thus, there is a need to propose a method for improvement.

According to the principle of heat balance and the temperature gradient characteristics of concrete around cooling pipes, a method to calculate the water temperature along cooling pipes using the buried pipe element method is proposed in this study. By comparing the results of a discrete algorithm and the buried pipe element method, it was discovered that the convection coefficient of the cooling pipe boundary for the buried pipe element method is only related to the thermal conductivity of concrete; therefore, it can be calculated by inverse analysis.

The results show that the buried pipe element method can achieve the same accuracy as the discrete method and simulate the temperature field of mass concrete with cooling pipes efficiently and accurately.

This new method can improve the calculation accuracy of the embedded element method and make the calculation results more reasonable and reliable.