ABSTRACT
Digital contact tracing has been recently advocated by China and many countries as part of digital prevention measures on COVID-19. Controversies have been raised about their effectiveness in practice as it remains open how they can be fully utilized to control COVID-19. In this article, we show that an abundance of information can be extracted from digital contact tracing for COVID-19 prevention and control. Specifically, we construct a temporal contact graph that quantifies the daily contacts between infectious and susceptible individuals by exploiting a large volume of location-related data contributed by 10,527,737 smartphone users in Wuhan, China. The temporal contact graph reveals five time-varying indicators can accurately capture actual contact trends at population level, demonstrating that travel restrictions (e.g., city lockdown) in Wuhan played an important role in containing COVID-19. We reveal a strong correlation between the contacts level and the epidemic size, and estimate several significant epidemiological parameters (e.g., serial interval). We also show that user participation rate exerts higher influence on situation evaluation than user upload rate does, indicating a sub-sampled dataset would be as good at prediction. At individual level, however, the temporal contact graph plays a limited role, since the behavior distinction between the infected and uninfected individuals are not substantial. The revealed results can tell the effectiveness of digital contact tracing against COVID-19, providing guidelines for governments to implement interventions using information technology.
ABSTRACT
Real-time tracking of video sports targets has been widely used in the sports industry. In order to further improve the accuracy of real-time tracking of sports targets, this paper proposes a real-time tracking method for sports targets in smart cities in the context of Internet+. This method collects data and information on the targets in the sports process, fully considers the diversity of the sports process, and performs real-time tracking and detection of the upgraded sports targets. Finally, the experimental research shows that the method in this paper can track the target accurately and quickly in real time during the movement process, and the accuracy and real-time tracking are relatively better than other tracking methods, which can be used as a powerful tool for subsequent moving target tracking.