Digital signature has recently played an increasingly important role in cyberspace security.Most of them are based on the public key cryptography.Public key cryptography is a mainstream cryptographic algorithm system ...Digital signature has recently played an increasingly important role in cyberspace security.Most of them are based on the public key cryptography.Public key cryptography is a mainstream cryptographic algorithm system that has been widely used in cyberspace security in recent years.The most classic public key cryptography algorithm is RSA and its difficulty is based on the large integer decomposition problem.In 2017,ISRSAC was proposed by M.Thangaval.ISRSAC has made security improvements to the RSA algorithm by increasing the complexity in factoring the value of modulus‘n’.A digital signature algorithm based on ISRSAC algorithm was completed in this paper,and furthermore,a proxy signature algorithm based on ISRSAC and two kinds of multi-signature algorithms were presented,which include sequential multi-signature and broadcasting multi-signature.展开更多
Monolayer tungsten disulfide （WS2）, a typical member of the semiconducting transition metal dichalcogenide family has drawn considerable interest because of its unique properties. Intriguingly the edge of WS2 exhibi...Monolayer tungsten disulfide （WS2）, a typical member of the semiconducting transition metal dichalcogenide family has drawn considerable interest because of its unique properties. Intriguingly the edge of WS2 exhibits an ideal hydrogen binding energy which makes WS2 a potential alternative to Pt-based electrocatalysts for the hydrogen evolution reaction （HER）. Here, we demonstrate for the first time the successful synthesis of uniform monolayer WS2 nanosheets on centimeter- scale Au foils using a facile, low-pressure chemical vapor deposition method. The edge lengths of the universally observed triangular WS2 nanosheets are tunable from -100 to N1,000 nm. The WS2 nanosheets on Au foils featuring abundant edges were then discovered to be efficient catalysts for the HER, exhibiting a rather high exchange current density of -30.20 μA/cm2 and a small onset potential of Nl10 mV. The effects of coverage and domain size （which correlate closely with the active edge density of WS2） on the electrocatalytic activity were investigated. This work not only provides a novel route toward the batch-production of monolayer WS2 via the introduction of metal foil substrates but also opens up its direct application for facile HER.展开更多
A secret sharing scheme permits a secret to be shared among participants in such a way that only qualified subsets of participants can recover the secret. Secret sharing is useful in management of cryptographic keys. ...A secret sharing scheme permits a secret to be shared among participants in such a way that only qualified subsets of participants can recover the secret. Secret sharing is useful in management of cryptographic keys. Based on identity, we analyze the secret sharing scheme among weighted participants. Then we present a dynamic scheme about secret sharing among weighted participants. At last, we analyze the secret sharing scheme among weighted participants, which can make all weighted participants verifiable and dynamic.展开更多
基金This work has been performed in National Natural Science Foundation of China(No.61772047,61372069)the Fundamental Research Funds for the Central Universities(No.328201902)+2 种基金National Defense Pre-research Foundation,SRF for ROCS,SEM(JY0600090102)111 project(No.B08038)China Civil Aviation Information Technology Research Base Funded Project(CAAC-ITRB-201705).
文摘Digital signature has recently played an increasingly important role in cyberspace security.Most of them are based on the public key cryptography.Public key cryptography is a mainstream cryptographic algorithm system that has been widely used in cyberspace security in recent years.The most classic public key cryptography algorithm is RSA and its difficulty is based on the large integer decomposition problem.In 2017,ISRSAC was proposed by M.Thangaval.ISRSAC has made security improvements to the RSA algorithm by increasing the complexity in factoring the value of modulus‘n’.A digital signature algorithm based on ISRSAC algorithm was completed in this paper,and furthermore,a proxy signature algorithm based on ISRSAC and two kinds of multi-signature algorithms were presented,which include sequential multi-signature and broadcasting multi-signature.
文摘Monolayer tungsten disulfide （WS2）, a typical member of the semiconducting transition metal dichalcogenide family has drawn considerable interest because of its unique properties. Intriguingly the edge of WS2 exhibits an ideal hydrogen binding energy which makes WS2 a potential alternative to Pt-based electrocatalysts for the hydrogen evolution reaction （HER）. Here, we demonstrate for the first time the successful synthesis of uniform monolayer WS2 nanosheets on centimeter- scale Au foils using a facile, low-pressure chemical vapor deposition method. The edge lengths of the universally observed triangular WS2 nanosheets are tunable from -100 to N1,000 nm. The WS2 nanosheets on Au foils featuring abundant edges were then discovered to be efficient catalysts for the HER, exhibiting a rather high exchange current density of -30.20 μA/cm2 and a small onset potential of Nl10 mV. The effects of coverage and domain size （which correlate closely with the active edge density of WS2） on the electrocatalytic activity were investigated. This work not only provides a novel route toward the batch-production of monolayer WS2 via the introduction of metal foil substrates but also opens up its direct application for facile HER.
基金The research is supported by Research Funds of Information Security and Secrecy Laboratory of Beijing Electronic Science ＆： Technology Institute under Grant No. YZDJ0712, partially by National Basic Research Program under Grant No. 2004CB318000, and Beijing Municipal Natural Science Foundation under Grant No. 406：3040.
文摘A secret sharing scheme permits a secret to be shared among participants in such a way that only qualified subsets of participants can recover the secret. Secret sharing is useful in management of cryptographic keys. Based on identity, we analyze the secret sharing scheme among weighted participants. Then we present a dynamic scheme about secret sharing among weighted participants. At last, we analyze the secret sharing scheme among weighted participants, which can make all weighted participants verifiable and dynamic.
