With the development and widespread use of blockchain in recent years,many projects have introduced blockchain technology to solve the growing security issues of the Industrial Internet of Things(IIoT).However,due to ...With the development and widespread use of blockchain in recent years,many projects have introduced blockchain technology to solve the growing security issues of the Industrial Internet of Things(IIoT).However,due to the conflict between the operational performance and security of the blockchain system and the compatibility issues with a large number of IIoT devices running together,the mainstream blockchain system cannot be applied to IIoT scenarios.In order to solve these problems,this paper proposes SBFT(Speculative Byzantine Consensus Protocol),a flexible and scalable blockchain consensus mechanism for the Industrial Internet of Things.SBFT has a consensus process based on speculation,improving the throughput and consensus speed of blockchain systems and reducing communication overhead.In order to improve the compatibility and scalability of the blockchain system,we select some nodes to participate in the consensus,and these nodes have better performance in the network.Since multiple properties determine node performance,we abstract the node selection problem as a joint optimization problem and use Dueling Deep Q Learning(DQL)to solve it.Finally,we evaluate the performance of the scheme through simulation,and the simulation results prove the superiority of our scheme.展开更多
Facing the ubiquitous corrosion threat,the great significance of developing high-performance protective materials with the dual function of self-healing defects and self-warning damage is extremely challenging.Herein,...Facing the ubiquitous corrosion threat,the great significance of developing high-performance protective materials with the dual function of self-healing defects and self-warning damage is extremely challenging.Herein,inspired by the biological skin and pearls,we proposed that the biological polyurethanes(PU)embedded with multiple dynamic bonds(reversible hydrogen bonds and aromatic disulfide bonds)were combined with polydopamine(PDA)/1,10-phenanthroline(Phen)/graphene oxide(GO)(PPG)nanosheets(PDA encapsulated GO with Phen)to obtain a versatile nacre structure polymer with the interface hydrogen bond between PPG and PU matrix.The biomimetic polymer not only guarantees ultrahigh toughness(116.1 MJ·m^(-3))and abnormal elongation(2320%)but shows satisfactory repair performance(81%under 25℃ for 3 h),and the coating can accelerate damage recovery(87%)under near-infrared light(NIR)irradiation for 1 h due to the photothermal properties of PPG.The warning of damages in the coating can be enabled through the Phen chelation Fe^(2+)ions that bring in the corrosion reaction to produce a conspicuous red color,thereby achieving the active warning function of the bionic coating on defects for the first time.In addition,the electrochemical tests exhibit that the repair performance and protection effect of the biomimetic coating in 3.5 wt.%NaCl solution are also trustworthy,and this highly reliable bio-based bionic coating brings a revolutionary program to inaugurate multifunctional and high-performance intelligent materials under harsh environments.展开更多
文摘With the development and widespread use of blockchain in recent years,many projects have introduced blockchain technology to solve the growing security issues of the Industrial Internet of Things(IIoT).However,due to the conflict between the operational performance and security of the blockchain system and the compatibility issues with a large number of IIoT devices running together,the mainstream blockchain system cannot be applied to IIoT scenarios.In order to solve these problems,this paper proposes SBFT(Speculative Byzantine Consensus Protocol),a flexible and scalable blockchain consensus mechanism for the Industrial Internet of Things.SBFT has a consensus process based on speculation,improving the throughput and consensus speed of blockchain systems and reducing communication overhead.In order to improve the compatibility and scalability of the blockchain system,we select some nodes to participate in the consensus,and these nodes have better performance in the network.Since multiple properties determine node performance,we abstract the node selection problem as a joint optimization problem and use Dueling Deep Q Learning(DQL)to solve it.Finally,we evaluate the performance of the scheme through simulation,and the simulation results prove the superiority of our scheme.
基金This study was financially supported by the LingChuang Research Project of China National Nuclear Corporation(No.E041F212Z1).
文摘Facing the ubiquitous corrosion threat,the great significance of developing high-performance protective materials with the dual function of self-healing defects and self-warning damage is extremely challenging.Herein,inspired by the biological skin and pearls,we proposed that the biological polyurethanes(PU)embedded with multiple dynamic bonds(reversible hydrogen bonds and aromatic disulfide bonds)were combined with polydopamine(PDA)/1,10-phenanthroline(Phen)/graphene oxide(GO)(PPG)nanosheets(PDA encapsulated GO with Phen)to obtain a versatile nacre structure polymer with the interface hydrogen bond between PPG and PU matrix.The biomimetic polymer not only guarantees ultrahigh toughness(116.1 MJ·m^(-3))and abnormal elongation(2320%)but shows satisfactory repair performance(81%under 25℃ for 3 h),and the coating can accelerate damage recovery(87%)under near-infrared light(NIR)irradiation for 1 h due to the photothermal properties of PPG.The warning of damages in the coating can be enabled through the Phen chelation Fe^(2+)ions that bring in the corrosion reaction to produce a conspicuous red color,thereby achieving the active warning function of the bionic coating on defects for the first time.In addition,the electrochemical tests exhibit that the repair performance and protection effect of the biomimetic coating in 3.5 wt.%NaCl solution are also trustworthy,and this highly reliable bio-based bionic coating brings a revolutionary program to inaugurate multifunctional and high-performance intelligent materials under harsh environments.
基金financially supported by the National Natural Science Foundation of China(22175030)the Open Project of State Key Laboratory of Supramolecular Structure and Materials(sklssm202205)。
