AI applications have become ubiquitous,bringing significant convenience to various industries.In e-commerce,AI can enhance product recommendations for individuals and provide businesses with more accurate predictions ...AI applications have become ubiquitous,bringing significant convenience to various industries.In e-commerce,AI can enhance product recommendations for individuals and provide businesses with more accurate predictions for market strategy development.However,if the data used for AI applications is damaged or lost,it will inevitably affect the effectiveness of these AI applications.Therefore,it is essential to verify the integrity of e-commerce data.Although existing Provable Data Possession(PDP)protocols can verify the integrity of cloud data,they are not suitable for e-commerce scenarios due to the limited computational capabilities of edge servers,which cannot handle the high computational overhead of generating homomorphic verification tags in PDP.To address this issue,we propose PDP with Outsourced Tag Generation for AI-driven e-commerce,which outsources the computation of homomorphic verification tags to cloud servers while introducing a lightweight verification method to ensure that the tags match the uploaded data.Additionally,the proposed scheme supports dynamic operations such as adding,deleting,and modifying data,enhancing its practicality.Finally,experiments show that the additional computational overhead introduced by outsourcing homomorphic verification tags is acceptable compared to the original PDP.展开更多
Provable Data Possession(PDP)schemes have long been proposed to solve problem of how to check the integrity of data stored in cloud service without downloading.However,with the emerging of network consisting of low pe...Provable Data Possession(PDP)schemes have long been proposed to solve problem of how to check the integrity of data stored in cloud service without downloading.However,with the emerging of network consisting of low performance devices such as Internet of Things,we find that there are still two obstacles for applying PDP schemes.The first one is the heavy computation overhead in generating tags for data blocks,which is essential for setting up any PDP scheme.The other one is how to resist collusion attacks from third party auditors with any possible entities participating the auditing.In this paper,we propose a novel blockchain-based light-weighted PDP scheme for low performance devices,with an instance deployed on a cloud server.We design a secure outsourced tag generating method for low performance devices,which enables a kind of“hash-sign-switch”two-phase tag computing.With this method,users with low performance devices can employ third party auditors to compute modular exponential operations that accounts for the largest portion of computation overhead in tag generation,without leaking their data content.Chaincodes in blockchain network ensure the correctness of such outsourcing and prevent collusion attacks.The security analysis and performance evaluation prove that our scheme is both secure and efficient.展开更多
To check the remote data integrity in cloud computing,we have proposed an efficient and full data dynamic provable data possession（PDP） scheme that uses a SN（serial number）-BN（block number） table to support data...To check the remote data integrity in cloud computing,we have proposed an efficient and full data dynamic provable data possession（PDP） scheme that uses a SN（serial number）-BN（block number） table to support data block update.In this article,we first analyze and test its performance in detail.The result shows that our scheme is efficient with low computation,storage,and communication costs.Then,we discuss how to extend the dynamic scheme to support other features,including public auditability,privacy preservation,fairness,and multiple-replica checking.After being extended,a comprehensive PDP scheme that has high efficiency and satisfies all main requirements is provided.展开更多
Increment of mobile cloud video motivates mobile users to utilize cloud storage service to address their demands,cloud storage provider always furnish a location-independent platform for managing user's data.Howev...Increment of mobile cloud video motivates mobile users to utilize cloud storage service to address their demands,cloud storage provider always furnish a location-independent platform for managing user's data.However,mobile users wonder if their cloud video data leakage or dynamic migration to illegal service providers.In this paper,we design a novel provable data possession protocol based on data geographic location attribute,which allows data owner to auditing the integrity of their video data,which put forward an ideal choice for remote data possession checking in the mobile cloud storage.In our proposed scheme,we check out whether the video data dynamic migrate to an unspecified location(such as:overseas)by adding data geographic location attribute tag into provable data possession protocol.Moreover,we make sure the security of our proposed scheme under the Computational Diffic-Hellman assumption.The analysis and experiment results demonstrate that our proposed scheme is provably secure and efficient.展开更多
Nowadays, an increasing number of persons choose to outsource their computing demands and storage demands to the Cloud. In order to ensure the integrity of the data in the untrusted Cloud, especially the dynamic files...Nowadays, an increasing number of persons choose to outsource their computing demands and storage demands to the Cloud. In order to ensure the integrity of the data in the untrusted Cloud, especially the dynamic files which can be updated online, we propose an improved dynamic provable data possession model. We use some homomorphic tags to verify the integrity of the file and use some hash values generated by some secret values and tags to prevent replay attack and forgery attack. Compared with previous works, our proposal reduces the computational and communication complexity from O(logn) to O(1). We did some experiments to ensure this improvement and extended the model to file sharing situation.展开更多
Transilvania is a province of the actual state of Romania, geographically situated in the middle of the country, in the inner arch of the Carpathians. Starting with the 10th century, the territory of Transilvania beca...Transilvania is a province of the actual state of Romania, geographically situated in the middle of the country, in the inner arch of the Carpathians. Starting with the 10th century, the territory of Transilvania became attractive for the neighboring Hungarian royalty and later on, in the 1 lth century it was annexed into Hungary. For a better control of the newly annexed territory and in order to convert the orthodox population to Catholicism, the Hungarian rulers brought the Szeklers to Transilvania and two centuries later, German originating populations, from Rhine, Luxemburg, and Saxony （the name of Sas people, or Saxon of Transilvania derives from ＂Saxony＂）. The aim of this paper is to focus on the Sighisoara County, namely on the easement of certain areas for temporary or permanent maintenance or use by the church and hospitals in the region. That was a common practice in Medieval Europe aimed at ensuring the survival means for these institutions. However, it was not the only one to serve this goal. There were also donations on behalf of various people or allocations of money by the county authorities. The documents attesting this are unpublished, unedited and are to be found in the archives of the Brasov County, Budapest, and Vienna. They are the stepping stone of this paper and hence, they grant its originality. The objectives of the paper are to bring arguments in favor of the thesis that community money was directed towards meeting the needs of the hospitals, as well as towards supporting the widows, the orphans, and the needy ones. Worth noting in this respect is the management of the funds ceded to the church and county hospitals and that actually benefitted the whole community. Moreover, the paper also emphasizes the role played by education, since the latter is an important landmark for a community＇s development level展开更多
The system of bona fide acquisition of movables is a very important system in civil law since modem times. However, in modem society, the further development of concept delivery makes the phenomenon of separation betw...The system of bona fide acquisition of movables is a very important system in civil law since modem times. However, in modem society, the further development of concept delivery makes the phenomenon of separation between possession and ownership become more and more universal. There is a potential conflict between possession reform and the announcement of property right of property as a sign of delivery, which has been brought up again in civil law circles. Based on the measure of interest and value analysis, on the possession case of bona fide acquisition system is discussed and reflection, in under the bona fide possession of the application, the modified say. With a view to China＇ s ongoing property rights legislation to benefit.展开更多
“Face to face With Hurricane Camilleisa Piece of narration writ-ten by Joseph P.Blank.It has been adopted by text-book compilers of various countries ever since its first publication in The Readers Digest,March1970.A...“Face to face With Hurricane Camilleisa Piece of narration writ-ten by Joseph P.Blank.It has been adopted by text-book compilers of various countries ever since its first publication in The Readers Digest,March1970.A Searlyas1973,Nat-aliC.展开更多
From the perspective of feminism, by analyzing single intellectual women's living states in enclosed personal spaces, andcomparing their different spatial changes triggered by external intrusions, this essay inten...From the perspective of feminism, by analyzing single intellectual women's living states in enclosed personal spaces, andcomparing their different spatial changes triggered by external intrusions, this essay intends to explore Byatt's ambivalent attitudestowards the feminists' pursuit for a room of one's own, and point out the significance of harmonious co-existence between men andwomen to female identity construction.展开更多
A.S.Byatt's Possession has its own appraisal of public and critic alike for its original structure, as well as for the novelty and complexity of its themes. With Northrop Frye's archetypal criticism, this pape...A.S.Byatt's Possession has its own appraisal of public and critic alike for its original structure, as well as for the novelty and complexity of its themes. With Northrop Frye's archetypal criticism, this paper analyzes the epic poems"The Garden of Proserpina"so as to identify the hidden creation theme from paradise archetype.展开更多
The author of the paper analyzes the story"Glass Coffin"in A. S. Byatt's Possession and compares it with Brothers Grimm's fairy tale with the same name. Through the study, the author identifies the q...The author of the paper analyzes the story"Glass Coffin"in A. S. Byatt's Possession and compares it with Brothers Grimm's fairy tale with the same name. Through the study, the author identifies the quest motif from our modern hero's discovery journey in Possession.展开更多
Metal nanoclusters(MNCs)possess distinct chemical properties due to their diverse electronic structures.As a class of promising model catalysts,it is of importance to explore the relationship between their structures ...Metal nanoclusters(MNCs)possess distinct chemical properties due to their diverse electronic structures.As a class of promising model catalysts,it is of importance to explore the relationship between their structures and properties.However,it is still challenging to get highly active and stable MNCs as surface ligands can hinder their activities,while a complete lack of surface ligand protection can lead to instability.To address this concern,here a series of Pd_(6)nanoclusters(NCs)with varying ligand amounts were synthesized by using Pd_(6)(SC_(6)(C_(2))H_(17))_(12)as precursor and single-walled carbon nanotube(s-CNT)as carrier through treating the composite at different temperatures and times.展开更多
Traditional Chinese medicine(TCM)possesses original theoretical advantages and thousands of years of human experience of its application and plays an important role in the prevention and treatment of infectious diseas...Traditional Chinese medicine(TCM)possesses original theoretical advantages and thousands of years of human experience of its application and plays an important role in the prevention and treatment of infectious diseases and major chronic illnesses.With the support of national policies,the advantages of the“five major resources”of TCM are gradually being realized,ushering the enterprise and industry of TCM into a new era of high-quality development.展开更多
Currently,there is a growing trend among users to store their data in the cloud.However,the cloud is vulnerable to persistent data corruption risks arising from equipment failures and hacker attacks.Additionally,when ...Currently,there is a growing trend among users to store their data in the cloud.However,the cloud is vulnerable to persistent data corruption risks arising from equipment failures and hacker attacks.Additionally,when users perform file operations,the semantic integrity of the data can be compromised.Ensuring both data integrity and semantic correctness has become a critical issue that requires attention.We introduce a pioneering solution called Sec-Auditor,the first of its kind with the ability to verify data integrity and semantic correctness simultaneously,while maintaining a constant communication cost independent of the audited data volume.Sec-Auditor also supports public auditing,enabling anyone with access to public information to conduct data audits.This feature makes Sec-Auditor highly adaptable to open data environments,such as the cloud.In Sec-Auditor,users are assigned specific rules that are utilized to verify the accuracy of data semantic.Furthermore,users are given the flexibility to update their own rules as needed.We conduct in-depth analyses of the correctness and security of Sec-Auditor.We also compare several important security attributes with existing schemes,demonstrating the superior properties of Sec-Auditor.Evaluation results demonstrate that even for time-consuming file upload operations,our solution is more efficient than the comparison one.展开更多
Progress in cloud computing makes group data sharing in outsourced storage a reality.People join in group and share data with each other,making team work more convenient.This new application scenario also faces data s...Progress in cloud computing makes group data sharing in outsourced storage a reality.People join in group and share data with each other,making team work more convenient.This new application scenario also faces data security threats,even more complex.When a user quit its group,remaining data block signatures must be re-signed to ensure security.Some researchers noticed this problem and proposed a few works to relieve computing overhead on user side.However,considering the privacy and security need of group auditing,there still lacks a comprehensive solution to implement secure group user revocation,supporting identity privacy preserving and collusion attack resistance.Aiming at this target,we construct a concrete scheme based on ring signature and smart contracts.We introduce linkable ring signature to build a kind of novel meta data for integrity proof enabling anonymous verification.And the new meta data supports secure revocation.Meanwhile,smart contracts are using for resisting possible collusion attack and malicious re-signing computation.Under the combined effectiveness of both signature method and blockchain smart contracts,our proposal supports reliable user revocation and signature re-signing,without revealing any user identity in the whole process.Security and performance analysis compared with previous works prove that the proposed scheme is feasible and efficient.展开更多
With the growing trend toward using cloud storage,the problem of efficiently checking and proving data integrity needs more consideration.Many cryptography and security schemes,such as PDP(Provable Data Possession) an...With the growing trend toward using cloud storage,the problem of efficiently checking and proving data integrity needs more consideration.Many cryptography and security schemes,such as PDP(Provable Data Possession) and POR(Proofs of Retrievability) were proposed for this problem.Although many efficient schemes for static data have been constructed,only a few dynamic schemes exist,such as DPDP(Dynamic Provable Data Possession).But the DPDP scheme falls short when updates are not proportional to a fixed block size.The FlexList-based Dynamic Provable Data Possession(FlexDPDP) was an optimized scheme for DPDP.However,the update operations(insertion,remove,modification)in Flex DPDP scheme only apply to single node at a time,while multiple consecutive nodes operation is more common in practice.To solve this problem,we propose optimized algorithms for multiple consecutive nodes,which including MultiNodes Insert and Verification,MultiNodes Remove and Verification,MultiNodes Modify and Verification.The cost of our optimized algorithms is also analyzed.For m consecutive nodes,an insertion takes O(m) + O(log N) + O(log m),where N is the number of leaf nodes of FlexList,a remove takes O(log/V),and a modification is the same as the original algorithm.Finally,we compare the optimized algorithms with original FlexList through experiences,and the results show that our scheme has the higher efficiency of time and space.展开更多
This paper is intended to forecast the demand of the car market and the quantity of car possession in our country in 2000 by means of two statistics methods, i.e. tendency inference and regression analysis, and then i...This paper is intended to forecast the demand of the car market and the quantity of car possession in our country in 2000 by means of two statistics methods, i.e. tendency inference and regression analysis, and then its future growth tendency and market demand in our country are analyzed, according to the strategy requirement and the actual facts of our car industry development.展开更多
基金funded by the Taiwan Comprehensive University System and the National Science and Technology Council of Taiwan under grant number NSTC 111-2410-H-019-006-MY3Additionally,this work was financially/partially supported by the Advanced Institute of Manufacturing with High-tech Innovations(AIM-HI)from the Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education(MOE)in Taiwan+1 种基金the National Natural Science Foundation of China,No.62402444the Zhejiang Provincial Natural Science Foundation of China,No.LQ24F020012.
文摘AI applications have become ubiquitous,bringing significant convenience to various industries.In e-commerce,AI can enhance product recommendations for individuals and provide businesses with more accurate predictions for market strategy development.However,if the data used for AI applications is damaged or lost,it will inevitably affect the effectiveness of these AI applications.Therefore,it is essential to verify the integrity of e-commerce data.Although existing Provable Data Possession(PDP)protocols can verify the integrity of cloud data,they are not suitable for e-commerce scenarios due to the limited computational capabilities of edge servers,which cannot handle the high computational overhead of generating homomorphic verification tags in PDP.To address this issue,we propose PDP with Outsourced Tag Generation for AI-driven e-commerce,which outsources the computation of homomorphic verification tags to cloud servers while introducing a lightweight verification method to ensure that the tags match the uploaded data.Additionally,the proposed scheme supports dynamic operations such as adding,deleting,and modifying data,enhancing its practicality.Finally,experiments show that the additional computational overhead introduced by outsourcing homomorphic verification tags is acceptable compared to the original PDP.
基金The work is supported by the National Key Research and Development Program of China(No.2018YFC1604002)the National Natural Science Foundation of China(Nos.U1836204,U1936208,U1936216 and 62002197).
文摘Provable Data Possession(PDP)schemes have long been proposed to solve problem of how to check the integrity of data stored in cloud service without downloading.However,with the emerging of network consisting of low performance devices such as Internet of Things,we find that there are still two obstacles for applying PDP schemes.The first one is the heavy computation overhead in generating tags for data blocks,which is essential for setting up any PDP scheme.The other one is how to resist collusion attacks from third party auditors with any possible entities participating the auditing.In this paper,we propose a novel blockchain-based light-weighted PDP scheme for low performance devices,with an instance deployed on a cloud server.We design a secure outsourced tag generating method for low performance devices,which enables a kind of“hash-sign-switch”two-phase tag computing.With this method,users with low performance devices can employ third party auditors to compute modular exponential operations that accounts for the largest portion of computation overhead in tag generation,without leaking their data content.Chaincodes in blockchain network ensure the correctness of such outsourcing and prevent collusion attacks.The security analysis and performance evaluation prove that our scheme is both secure and efficient.
基金Supported by the National Basic"863"Research Program of China(2012CB315901)
文摘To check the remote data integrity in cloud computing,we have proposed an efficient and full data dynamic provable data possession（PDP） scheme that uses a SN（serial number）-BN（block number） table to support data block update.In this article,we first analyze and test its performance in detail.The result shows that our scheme is efficient with low computation,storage,and communication costs.Then,we discuss how to extend the dynamic scheme to support other features,including public auditability,privacy preservation,fairness,and multiple-replica checking.After being extended,a comprehensive PDP scheme that has high efficiency and satisfies all main requirements is provided.
基金supported in part by National High Tech Research and Development Program(863 Program)of China(No.2015 AA016005)
文摘Increment of mobile cloud video motivates mobile users to utilize cloud storage service to address their demands,cloud storage provider always furnish a location-independent platform for managing user's data.However,mobile users wonder if their cloud video data leakage or dynamic migration to illegal service providers.In this paper,we design a novel provable data possession protocol based on data geographic location attribute,which allows data owner to auditing the integrity of their video data,which put forward an ideal choice for remote data possession checking in the mobile cloud storage.In our proposed scheme,we check out whether the video data dynamic migrate to an unspecified location(such as:overseas)by adding data geographic location attribute tag into provable data possession protocol.Moreover,we make sure the security of our proposed scheme under the Computational Diffic-Hellman assumption.The analysis and experiment results demonstrate that our proposed scheme is provably secure and efficient.
基金supported by Major Program of Shanghai Science and Technology Commission under Grant No.10DZ1500200Collaborative Applied Research and Development Project between Morgan Stanley and Shanghai Jiao Tong University, China
文摘Nowadays, an increasing number of persons choose to outsource their computing demands and storage demands to the Cloud. In order to ensure the integrity of the data in the untrusted Cloud, especially the dynamic files which can be updated online, we propose an improved dynamic provable data possession model. We use some homomorphic tags to verify the integrity of the file and use some hash values generated by some secret values and tags to prevent replay attack and forgery attack. Compared with previous works, our proposal reduces the computational and communication complexity from O(logn) to O(1). We did some experiments to ensure this improvement and extended the model to file sharing situation.
文摘Transilvania is a province of the actual state of Romania, geographically situated in the middle of the country, in the inner arch of the Carpathians. Starting with the 10th century, the territory of Transilvania became attractive for the neighboring Hungarian royalty and later on, in the 1 lth century it was annexed into Hungary. For a better control of the newly annexed territory and in order to convert the orthodox population to Catholicism, the Hungarian rulers brought the Szeklers to Transilvania and two centuries later, German originating populations, from Rhine, Luxemburg, and Saxony （the name of Sas people, or Saxon of Transilvania derives from ＂Saxony＂）. The aim of this paper is to focus on the Sighisoara County, namely on the easement of certain areas for temporary or permanent maintenance or use by the church and hospitals in the region. That was a common practice in Medieval Europe aimed at ensuring the survival means for these institutions. However, it was not the only one to serve this goal. There were also donations on behalf of various people or allocations of money by the county authorities. The documents attesting this are unpublished, unedited and are to be found in the archives of the Brasov County, Budapest, and Vienna. They are the stepping stone of this paper and hence, they grant its originality. The objectives of the paper are to bring arguments in favor of the thesis that community money was directed towards meeting the needs of the hospitals, as well as towards supporting the widows, the orphans, and the needy ones. Worth noting in this respect is the management of the funds ceded to the church and county hospitals and that actually benefitted the whole community. Moreover, the paper also emphasizes the role played by education, since the latter is an important landmark for a community＇s development level
文摘The system of bona fide acquisition of movables is a very important system in civil law since modem times. However, in modem society, the further development of concept delivery makes the phenomenon of separation between possession and ownership become more and more universal. There is a potential conflict between possession reform and the announcement of property right of property as a sign of delivery, which has been brought up again in civil law circles. Based on the measure of interest and value analysis, on the possession case of bona fide acquisition system is discussed and reflection, in under the bona fide possession of the application, the modified say. With a view to China＇ s ongoing property rights legislation to benefit.
文摘“Face to face With Hurricane Camilleisa Piece of narration writ-ten by Joseph P.Blank.It has been adopted by text-book compilers of various countries ever since its first publication in The Readers Digest,March1970.A Searlyas1973,Nat-aliC.
文摘From the perspective of feminism, by analyzing single intellectual women's living states in enclosed personal spaces, andcomparing their different spatial changes triggered by external intrusions, this essay intends to explore Byatt's ambivalent attitudestowards the feminists' pursuit for a room of one's own, and point out the significance of harmonious co-existence between men andwomen to female identity construction.
文摘A.S.Byatt's Possession has its own appraisal of public and critic alike for its original structure, as well as for the novelty and complexity of its themes. With Northrop Frye's archetypal criticism, this paper analyzes the epic poems"The Garden of Proserpina"so as to identify the hidden creation theme from paradise archetype.
文摘The author of the paper analyzes the story"Glass Coffin"in A. S. Byatt's Possession and compares it with Brothers Grimm's fairy tale with the same name. Through the study, the author identifies the quest motif from our modern hero's discovery journey in Possession.
基金financially supported by the Natural Science Foundation of Guangxi,China(Nos.2019GXNSFGA245003 and 2021GXNSFBA220058)the National Natural Science Foundation of China(Nos.22272036 and 22362008)+2 种基金Guangxi Technology Base and Talent Subject,China(GUIKE AD23026272)Guangxi Normal University Research Grant,China(No.2022TD)Innovation Project of Guangxi Graduate Education(No.XYCSR2023018)。
文摘Metal nanoclusters(MNCs)possess distinct chemical properties due to their diverse electronic structures.As a class of promising model catalysts,it is of importance to explore the relationship between their structures and properties.However,it is still challenging to get highly active and stable MNCs as surface ligands can hinder their activities,while a complete lack of surface ligand protection can lead to instability.To address this concern,here a series of Pd_(6)nanoclusters(NCs)with varying ligand amounts were synthesized by using Pd_(6)(SC_(6)(C_(2))H_(17))_(12)as precursor and single-walled carbon nanotube(s-CNT)as carrier through treating the composite at different temperatures and times.
基金supported by the Strategic Research and Consultation Project of the Chinese Academy of Engineering(2023-PP-05,2025-PP-15)。
文摘Traditional Chinese medicine(TCM)possesses original theoretical advantages and thousands of years of human experience of its application and plays an important role in the prevention and treatment of infectious diseases and major chronic illnesses.With the support of national policies,the advantages of the“five major resources”of TCM are gradually being realized,ushering the enterprise and industry of TCM into a new era of high-quality development.
基金This research was supported by the Qinghai Provincial High-End Innovative and Entrepreneurial Talents Project.
文摘Currently,there is a growing trend among users to store their data in the cloud.However,the cloud is vulnerable to persistent data corruption risks arising from equipment failures and hacker attacks.Additionally,when users perform file operations,the semantic integrity of the data can be compromised.Ensuring both data integrity and semantic correctness has become a critical issue that requires attention.We introduce a pioneering solution called Sec-Auditor,the first of its kind with the ability to verify data integrity and semantic correctness simultaneously,while maintaining a constant communication cost independent of the audited data volume.Sec-Auditor also supports public auditing,enabling anyone with access to public information to conduct data audits.This feature makes Sec-Auditor highly adaptable to open data environments,such as the cloud.In Sec-Auditor,users are assigned specific rules that are utilized to verify the accuracy of data semantic.Furthermore,users are given the flexibility to update their own rules as needed.We conduct in-depth analyses of the correctness and security of Sec-Auditor.We also compare several important security attributes with existing schemes,demonstrating the superior properties of Sec-Auditor.Evaluation results demonstrate that even for time-consuming file upload operations,our solution is more efficient than the comparison one.
基金The work is supported by the National Key Research and Development Program of China(No.2018YFC1604002)the National Natural Science Foundation of China(No.U1836204,No.U1936208,No.U1936216,No.62002197).
文摘Progress in cloud computing makes group data sharing in outsourced storage a reality.People join in group and share data with each other,making team work more convenient.This new application scenario also faces data security threats,even more complex.When a user quit its group,remaining data block signatures must be re-signed to ensure security.Some researchers noticed this problem and proposed a few works to relieve computing overhead on user side.However,considering the privacy and security need of group auditing,there still lacks a comprehensive solution to implement secure group user revocation,supporting identity privacy preserving and collusion attack resistance.Aiming at this target,we construct a concrete scheme based on ring signature and smart contracts.We introduce linkable ring signature to build a kind of novel meta data for integrity proof enabling anonymous verification.And the new meta data supports secure revocation.Meanwhile,smart contracts are using for resisting possible collusion attack and malicious re-signing computation.Under the combined effectiveness of both signature method and blockchain smart contracts,our proposal supports reliable user revocation and signature re-signing,without revealing any user identity in the whole process.Security and performance analysis compared with previous works prove that the proposed scheme is feasible and efficient.
基金supported in part by the National Natural Science Foundation of China under Grant No.61440014&&No.61300196the Liaoning Province Doctor Startup Fundunder Grant No.20141012+2 种基金the Liaoning Province Science and Technology Projects under Grant No.2013217004the Shenyang Province Science and Technology Projects under Grant Nothe Fundamental Research Funds for the Central Universities under Grant No.N130317002 and No.N130317003
文摘With the growing trend toward using cloud storage,the problem of efficiently checking and proving data integrity needs more consideration.Many cryptography and security schemes,such as PDP(Provable Data Possession) and POR(Proofs of Retrievability) were proposed for this problem.Although many efficient schemes for static data have been constructed,only a few dynamic schemes exist,such as DPDP(Dynamic Provable Data Possession).But the DPDP scheme falls short when updates are not proportional to a fixed block size.The FlexList-based Dynamic Provable Data Possession(FlexDPDP) was an optimized scheme for DPDP.However,the update operations(insertion,remove,modification)in Flex DPDP scheme only apply to single node at a time,while multiple consecutive nodes operation is more common in practice.To solve this problem,we propose optimized algorithms for multiple consecutive nodes,which including MultiNodes Insert and Verification,MultiNodes Remove and Verification,MultiNodes Modify and Verification.The cost of our optimized algorithms is also analyzed.For m consecutive nodes,an insertion takes O(m) + O(log N) + O(log m),where N is the number of leaf nodes of FlexList,a remove takes O(log/V),and a modification is the same as the original algorithm.Finally,we compare the optimized algorithms with original FlexList through experiences,and the results show that our scheme has the higher efficiency of time and space.
文摘This paper is intended to forecast the demand of the car market and the quantity of car possession in our country in 2000 by means of two statistics methods, i.e. tendency inference and regression analysis, and then its future growth tendency and market demand in our country are analyzed, according to the strategy requirement and the actual facts of our car industry development.
