With the widespread of smart devices, a massive number of messages are sent through message applications every day. Currently, most message applications have been designed for single-receiver and group-receiver scenarios. Moreover, the sender device may send messages to multiple-receiver devices selected from the group device set. In this paper, we propose a lightweight hybrid signcryption scheme supporting the single-receiver and multiple-receiver scenarios, which are compatible with the group-receiver scenario. The formal verification results show that our scheme can offer confidentiality and authentication and is resistant to key-compromise impersonation (KCI) attacks. The evaluation results show that it provides an efficient solution with lower compute time and smaller payload size, which is suitable for lightweight message delivery.

A novel framework was proposed to measure atmospheric concentration of$\delta ^{13}C$using a multiwavelength integrated path differential absorption (IPDA) LiDAR. The spectroscopy range of the multiwavelength IPDA LiDAR is recommended from 2264.5 to 2265.5 cm$^{-1}$. Using the proposed retrieving method, the relative error of$\delta ^{13}C$retrievals would be within 0.16‰ under reasonable settings. Moreover, the proposed method shows reliable performances in different circumstances. It would be of great significance for exploring the characteristic of$\delta ^{13}C$in the ecosystem and anthropogenic emissions in the future.

Continued drought can lead to vegetation mortality and reduced carbon sink capacity of terrestrial ecosystems. However, the complexity of the causes and processes of drought has led to a limited understanding of how vegetation performances under drought. Here we used solar-induced chlorophyll fluorescence (SIF) and enhanced vegetation index (EVI) data to explore the impact of U.S Midwest drought on vegetation in 2012. At the whole study area and flux tower scale, SIF is more sensitive to the decrease in precipitation than EVI. SIF also can more accurately monitor the growth of vegetation under drought. SIF is an effective index for monitoring environmental stress on vegetation.