Aqueous rechargeable lithium-ion battery(ARLiB)is of specific importance due to the low-cost,environmentalfriendly properties.Recently,its energy denisty and cyclic life have been significantly enhanced,demonstarting ...Aqueous rechargeable lithium-ion battery(ARLiB)is of specific importance due to the low-cost,environmentalfriendly properties.Recently,its energy denisty and cyclic life have been significantly enhanced,demonstarting the potential for real applications.The improvement on key materials of ARLiB,ranging from cathode,anode and electrolyte,can finally ameliorate coresponding performance of full cell.Hereon,the cathode materials of ARLiBs are summerized as spinel oxides,layered oxides,olivine polyanion compounds olivine and Prussian blue analogues,while anode materials are classified into vanadium-based,polyanion,titanium-based and organic ones.Meanwhile,the strategies for better aqueous electrolytes are discussed from the aspects of salt concentration,solvent and interface.In the last part,issues challenging the commercialization of ARLiBs are provided as well as the suggestions for future research and development.展开更多
Data security is a significant issue in cloud storage systems. After outsourcing data to cloud servers, clients lose physical control over the data. To guarantee clients that their data is intact on the server side, s...Data security is a significant issue in cloud storage systems. After outsourcing data to cloud servers, clients lose physical control over the data. To guarantee clients that their data is intact on the server side, some mechanism is needed for clients to periodically check the integrity of their data. Proof of retrievability （PoR） is designed to ensure data integrity. However, most prior PoR schemes focus on static data, and existing dynamic PoR is inefficient. In this paper, we propose a new version of dynamic PoR that is based on a B＋ tree and a Merkle hash tree. We propose a novel authenticated data structure, called Cloud Merkle B＋ tree （CMBT）. By combining CMBT with the BES signature, dynamic operations such as insertion, deletion, and modification are supported. Compared with existing PoR schemes, our scheme improves worst-case overhead from O（n） to O（log n）.展开更多
基金One of the authors(S.C.)thanks China Scholarship Council for a fully funded PhD studentship to study at University of Warwick(No.201706690053).
文摘Aqueous rechargeable lithium-ion battery(ARLiB)is of specific importance due to the low-cost,environmentalfriendly properties.Recently,its energy denisty and cyclic life have been significantly enhanced,demonstarting the potential for real applications.The improvement on key materials of ARLiB,ranging from cathode,anode and electrolyte,can finally ameliorate coresponding performance of full cell.Hereon,the cathode materials of ARLiBs are summerized as spinel oxides,layered oxides,olivine polyanion compounds olivine and Prussian blue analogues,while anode materials are classified into vanadium-based,polyanion,titanium-based and organic ones.Meanwhile,the strategies for better aqueous electrolytes are discussed from the aspects of salt concentration,solvent and interface.In the last part,issues challenging the commercialization of ARLiBs are provided as well as the suggestions for future research and development.
基金supported in part by the US National Science Foundation under grant CNS-1115548 and a grant from Cisco Research
文摘Data security is a significant issue in cloud storage systems. After outsourcing data to cloud servers, clients lose physical control over the data. To guarantee clients that their data is intact on the server side, some mechanism is needed for clients to periodically check the integrity of their data. Proof of retrievability （PoR） is designed to ensure data integrity. However, most prior PoR schemes focus on static data, and existing dynamic PoR is inefficient. In this paper, we propose a new version of dynamic PoR that is based on a B＋ tree and a Merkle hash tree. We propose a novel authenticated data structure, called Cloud Merkle B＋ tree （CMBT）. By combining CMBT with the BES signature, dynamic operations such as insertion, deletion, and modification are supported. Compared with existing PoR schemes, our scheme improves worst-case overhead from O（n） to O（log n）.
