Research on building trust mechanism of farmers' online lending under the background of big data Research on actuarial statistical model and risk supervision of health insurance underthe background of big data Research on the collaborative innovation mechanism of information assurance in think tank decision support under the background of big data Research on the influence mechanism and path of new energy vehicle promotion under the background of double carbon Research on employee promotion mechanism of large enterprises in China from the perspective of big data Solution of logistics innovation development under the background of big data Research on the mechanism of educational intelligence resources sharing under the background of "internet +" research on Guan Liang and Feng Zikai's local painting practice under the background of their study in Japan