PVF-DA: Privacy-Preserving, Verifiable and FaultTolerant Data Aggregation in MEC

As an emergent-architecture, mobile edge computing shifts cloud service to the edge of networks. It can satisfy several desirable characteristics for Io T systems. To reduce communication pressure from Io T devices, data aggregation is a good candidate. However, data processing in MEC may suffer from many challenges, such as unverifiability of aggregated data, privacy-violation and fault-tolerance. To address these challenges, we propose PVF-DA: privacy-preserving, verifiable and fault-tolerant data aggregation in MEC based on aggregator-oblivious encryption and zero-knowledge-proof. The proposed scheme can not only provide privacy protection of the reported data, but also resist the collusion between MEC server and corrupted Io T devices. Furthermore, the proposed scheme has two outstanding features: verifiability and strong fault-tolerance. Verifiability can make Io T device to verify whether the reported sensing data is correctly aggregated. Strong fault-tolerance makes the aggregator to compute an aggregate even if one or several Io Ts fail to report their data. Finally, the detailed security proofs are shown that the proposed scheme can achieve security and privacy-preservation properties in MEC.

Systematic measurement and spatiotemporal evolution of agricultural versatility in China

In this study,the entropy weight method was used to measure the agricultural versatility of 30 provinces in China(excluding Tibet,Hong Kong,Macao,and Taiwan)from 2008 to 2019.In addition,the Theil index method and kernel density estimation were used to analyze the spatiotemporal characteristics of the agricultural versatility in each province.The results show that the agricultural product supply and social security functions rapidly developed,but the economic development was weak.From 2008 to 2019,the total functional index of agriculture increased by 6.74%;the functional index of the agricultural product supply,social security,and ecological services increased by 12.72%,5.53%,and 2.05%,respectively;and the functional index of economic development decreased by 1.32%.The development of agricultural multifunctions in China is regionally heterogeneous.Based on the Theil index method,the differences in the agricultural functions of the three regions are mainly due to intragroup differences.The contribution of intragroup differences of the eight economic regions is significantly lower than that of the three regions.However,intragroup differences dominate the agricultural product supply,economic development,and social security functions and intergroup differences control the ecological service function.The kernel density estimation curve shows that the overall agricultural functional evaluation index increased,among which the agricultural product supply function increased the most.