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The study aims to measure the contribution rate of scientific and technological progress of Shaanxi province and find out the main driving force of its economic development, which has important reference significance for formulating and implementing the economic and social development strategy of Shaanxi Province and other regions.

By comparing and referring to the advantages and disadvantages of existing research methods, this paper combined C-D production function and Solow residual method to calculate the elastic coefficient through neural network algorithm, and then calculated the contribution rate of technological innovation to economic growth in Shaanxi province as a whole and in various regions, analyzed and put forward reasonable suggestions.

The results show that the economic growth is mainly depends on capital investment, and the contribution rate of technological innovation to economic growth is low and fluctuates greatly. In the future, each region of Shaanxi should improve the ability of technological innovation to speed up the economic transformation to the intensive type.

To make the technological innovation in Shaanxi province and other regions play a more significant role in promoting economic growth and accelerate the productivity and economic transformation of Shaanxi Province, the following suggestions are put forward, strengthen the coordinated development of innovation and economy in all regions of Shaanxi. Second, this paper need to give full play to the role of policy support and incentives. Third, this paper need to improve the market system and vigorously support enterprise innovation. Fourth, use new and high technology to transform and upgrade industrial technology. Fifth, this paper need to speed up the development of high-quality personnel.

This study aims to provide guidance for the reliability of electronic packaging. The reliability of solder joints at extremely temperature thermal shock is critical for electronic equipment operating in the field of deep space exploration. In this study, the Sn3.0Ag0.5Cu (SAC305)/Cu solder joints were prepared and thermally shocked with temperatures ranging from −110°C to 110°C, to investigate the effects of extreme temperature thermal shock on the microstructural evolution and property deterioration of the solder joints.

The interfacial intermetallic compound (IMC) stress gradient was calculated through thermal stress theory, mechanism of voids/cracks initiation was clarified, and prediction of the service life was analyzed with the energy-based model.

It is found that the Ag₃Sn, IMC and cracks/voids had evolved significantly with the increase in the cycle period. The microstructure of the IMC changed from short rod-like morphology to scallop shape, the voids in the Cu₃Sn IMC layer continued to increase and integrate, forming larger diameter voids, etc. In addition, the shear strength of SAC305/Cu solder joints decreased gradually with the increase in thermal shock cycles, the fracture mode changes from ductile fracture mode to ductile-brittle mixed fracture mode after 500 cycles. The characteristic lifetime of the SAC305/Cu solder joints under the action of extreme thermal shock is about 1427.86 cycles.

This work provides guidance for the reliability of the solder joints at extremely temperature thermal shock.