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Objectives: In the case of uneven distribution of map features, the density difference breaks the visual balance and reduces the beauty of the map. A large number of spatial features are concentrated in the small area, resulting in the contradiction between the display of features and the size of the area. Map details are not prominent, which increases difficulties in obtaining spatial information and is not conducive to decision analysis. The uneven distribution of feature density in mapping area increases the difficulty of map expression. Conventional map expression cannot solve the problem of visual imbalance.Methods: Based on Gastner-Newman cartogram algorithm, this paper proposes a map transformation algorithm that balances the feature density and achieve consistent public perception. Various cartograms can be generated through five steps: Designing deformation unit scales, configuring density weight combination of features, applying linear diffusion equation, constructing deformation grids and mapping discrete control points. Results: Taking Qingxiu district of Nanning city, China as the research area, we select two scale deformation units of subdistrict and custom grid, and configure density weights with different combinations of point of interest and road network geometry features to generate various cartograms. The deformation measurement values of the deformation map are calculated respectively. After cognitive experiments, 56 questionnaires were ob‐ tained. Regarding the morphological control of the administrative map of Qingxiu District in Nanning, the parameters configurations should be controlled as in Sperimeter>0.975, Sperimeter area ratio>0.961 and Sshape ratio> 0.966. In this way, public cognition can be consistent. Conclusions: This study provides a new idea to solve the problem of uneven density of map features. The deformed map reaches visual balance.The area where the original features are dense increases while the area where the features are sparse decreases. By adjusting the deformation weight parameters to maintain the consistency of public map cognition. Subsequent‐ ly, we will further study how to determine the optimal parameter combination to achieve the optimal defor‐ mation expression and cognitive effect. [ABSTRACT FROM AUTHOR]

Speed is key to prevent and control major public health emergencies. For an efficient management, time, data, information, and resources are important factors. This paper summarizes the challenges in China’s response to the coronavirus disease 2019 （COVID-19）， and proposes an integration of vertical system and horizontal system, based on the idea of“let data run more, rely on accurate information, and outperform viruses with electromagnetic waves ”. Through all the analyses, we provide suggestions on improving China’s digital public health emergency management system for scientific and technological strategies, and they include: (1) establishing a standardized data epidemic information collection system to dynamically sense public sentiment; (2) building a public health big data center with a unified spatiotemporal benchmark to achieve cross regional and cross industry data aggregation, fusion, and sharing; (3) strengthening artificial intelligence technology for epidemic monitoring, forecasting, and risk research, and improving management accuracy and screening efficiency; (4) developing situation deduction and optimizing regulatory computing technology and services scientific dispatch and emergency command; (5) improving operating system mechanisms to ensure normal, safe and stable operations. [ABSTRACT FROM AUTHOR]