For the goals of security and privacy preservation,we propose a blind batch encryption-and public ledger-based data sharing protocol that allows the integrity of sensitive data to be audited by a public ledger and all...For the goals of security and privacy preservation,we propose a blind batch encryption-and public ledger-based data sharing protocol that allows the integrity of sensitive data to be audited by a public ledger and allows privacy information to be preserved.Data owners can tightly manage their data with efficient revocation and only grant one-time adaptive access for the fulfillment of the requester.We prove that our protocol is semanticallly secure,blind,and secure against oblivious requesters and malicious file keepers.We also provide security analysis in the context of four typical attacks.展开更多
To enhance the security of user data in the clouds,we present an adaptive and dynamic data encryption method to encrypt user data in the mobile phone before it is uploaded.Firstly,the adopted data encryption algorithm...To enhance the security of user data in the clouds,we present an adaptive and dynamic data encryption method to encrypt user data in the mobile phone before it is uploaded.Firstly,the adopted data encryption algorithm is not static and uniform.For each encryption,this algorithm is adaptively and dynamically selected from the algorithm set in the mobile phone encryption system.From the mobile phone's character,the detail encryption algorithm selection strategy is confirmed based on the user's mobile phone hardware information,personalization information and a pseudo-random number.Secondly,the data is rearranged with a randomly selected start position in the data before being encrypted.The start position's randomness makes the mobile phone data encryption safer.Thirdly,the rearranged data is encrypted by the selected algorithm and generated key.Finally,the analysis shows this method possesses the higher security because the more dynamics and randomness are adaptively added into the encryption process.展开更多
With increasing demand for data circulation,ensuring data security and privacy is paramount,specifically protecting privacy while maximizing utility.Blockchain,while decentralized and transparent,faces challenges in p...With increasing demand for data circulation,ensuring data security and privacy is paramount,specifically protecting privacy while maximizing utility.Blockchain,while decentralized and transparent,faces challenges in privacy protection and data verification,especially for sensitive data.Existing schemes often suffer from inefficiency and high overhead.We propose a privacy protection scheme using BGV homomorphic encryption and Pedersen Secret Sharing.This scheme enables secure computation on encrypted data,with Pedersen sharding and verifying the private key,ensuring data consistency and immutability.The blockchain framework manages key shards,verifies secrets,and aids security auditing.This approach allows for trusted computation without revealing the underlying data.Preliminary results demonstrate the scheme's feasibility in ensuring data privacy and security,making data available but not visible.This study provides an effective solution for data sharing and privacy protection in blockchain applications.展开更多
With the rapid development of information technology,IoT devices play a huge role in physiological health data detection.The exponential growth of medical data requires us to reasonably allocate storage space for clou...With the rapid development of information technology,IoT devices play a huge role in physiological health data detection.The exponential growth of medical data requires us to reasonably allocate storage space for cloud servers and edge nodes.The storage capacity of edge nodes close to users is limited.We should store hotspot data in edge nodes as much as possible,so as to ensure response timeliness and access hit rate;However,the current scheme cannot guarantee that every sub-message in a complete data stored by the edge node meets the requirements of hot data;How to complete the detection and deletion of redundant data in edge nodes under the premise of protecting user privacy and data dynamic integrity has become a challenging problem.Our paper proposes a redundant data detection method that meets the privacy protection requirements.By scanning the cipher text,it is determined whether each sub-message of the data in the edge node meets the requirements of the hot data.It has the same effect as zero-knowledge proof,and it will not reveal the privacy of users.In addition,for redundant sub-data that does not meet the requirements of hot data,our paper proposes a redundant data deletion scheme that meets the dynamic integrity of the data.We use Content Extraction Signature(CES)to generate the remaining hot data signature after the redundant data is deleted.The feasibility of the scheme is proved through safety analysis and efficiency analysis.展开更多
With the in-depth application of new technologies such as big data in education fields,the storage and sharing model of student education records data still faces many challenges in terms of privacy protection and eff...With the in-depth application of new technologies such as big data in education fields,the storage and sharing model of student education records data still faces many challenges in terms of privacy protection and efficient transmission.In this paper,we propose a data security storage and sharing scheme based on consortium blockchain,which is a credible search scheme without verification.In our scheme,the implementation of data security storage is using the blockchain and storage server together.In detail,the smart contract provides protection for data keywords,the storage server stores data after data masking,and the blockchain ensures the traceability of query transactions.The need for precise privacy data is achieved by constructing a dictionary.Cryptographic techniques such as AES and RSA are used for encrypted storage of data,keywords,and digital signatures.Security analysis and performance evaluation shows that the availability,high efficiency,and privacy-preserving can be achieved.Meanwhile,this scheme has better robustness compared to other educational records data sharing models.展开更多
This study developed a new methodology for analyzing the risk level of marine spill accidents from two perspectives,namely,marine traffic density and sensitive resources.Through a case study conducted in Busan,South K...This study developed a new methodology for analyzing the risk level of marine spill accidents from two perspectives,namely,marine traffic density and sensitive resources.Through a case study conducted in Busan,South Korea,detailed procedures of the methodology were proposed and its scalability was confirmed.To analyze the risk from a more detailed and microscopic viewpoint,vessel routes as hazard sources were delineated on the basis of automated identification system(AIS)big data.The outliers and errors of AIS big data were removed using the density-based spatial clustering of applications with noise algorithm,and a marine traffic density map was evaluated by combining all of the gridded routes.Vulnerability of marine environment was identified on the basis of the sensitive resource map constructed by the Korea Coast Guard in a similar manner to the National Oceanic and Atmospheric Administration environmental sensitivity index approach.In this study,aquaculture sites,water intake facilities of power plants,and beach/resort areas were selected as representative indicators for each category.The vulnerability values of neighboring cells decreased according to the Euclidean distance from the resource cells.Two resulting maps were aggregated to construct a final sensitive resource and traffic density(SRTD)risk analysis map of the Busan–Ulsan sea areas.We confirmed the effectiveness of SRTD risk analysis by comparing it with the actual marine spill accident records.Results show that all of the marine spill accidents in 2018 occurred within 2 km of high-risk cells(level 6 and above).Thus,if accident management and monitoring capabilities are concentrated on high-risk cells,which account for only 6.45%of the total study area,then it is expected that it will be possible to cope with most marine spill accidents effectively.展开更多
With the development of smart grid, operation and control of a power system can be realized through the power communication network, especially the power production and enterprise management business involve a large a...With the development of smart grid, operation and control of a power system can be realized through the power communication network, especially the power production and enterprise management business involve a large amount of sensitive information, and the requirements for data security and real-time transmission are gradually improved. In this paper, a new 9-dimensional(9D) complex chaotic system with quaternion is proposed for the encryption of smart grid data. Firstly, we present the mathematical model of the system, and analyze its attractors, bifurcation diagram, complexity,and 0–1 test. Secondly, the pseudo-random sequences are generated by the new chaotic system to encrypt power data.Finally, the proposed encryption algorithm is verified with power data and images in the smart grid, which can ensure the encryption security and real time. The verification results show that the proposed encryption scheme is technically feasible and available for power data and image encryption in smart grid.展开更多
In direct sequence spread spectrum communication both for satelliteto-ground and inter-satellite links, the system constrains due to radio frequency spectral occupation, channel data throughput and link performances i...In direct sequence spread spectrum communication both for satelliteto-ground and inter-satellite links, the system constrains due to radio frequency spectral occupation, channel data throughput and link performances in terms of data channel coding which might result in a signal structure where the symbol duration is shorter than the pseudo code period. This can generate some difficulties in the DSSS signal acquisition due to the polarity inversion caused by the data modulation. To eliminate the influence due to polarity inversion, this paper proposes a novel acquisition algorithm based on the simultaneous search of the code phase, data phase and Doppler frequency. In the proposed algorithm the data phase is predicted and the correlation period for the coherent integration can be set equal to the symbol duration. Then non-coherent accumulation over different symbol is implemented in order to enhance the acquisition algorithm sensitivity; the interval of non-coherent accumulation is the least common multiple between the symbol duration and the pseudo code period. The algorithm proposed can largely minimize the SNR loss caused by data polarity inversion and enhance acquisition performance without a noticeable increase in hardware complexity. Theoretical analysis, simulation and measured results verify the validity of the algorithm.展开更多
Despite that existing data sharing systems in online social networks （OSNs） propose to encrypt data before sharing, the multiparty access control of encrypted data has become a challenging issue. In this paper, we p...Despite that existing data sharing systems in online social networks （OSNs） propose to encrypt data before sharing, the multiparty access control of encrypted data has become a challenging issue. In this paper, we propose a secure data sharing scheme in 0SNs based on ciphertext-policy attribute- based proxy re-encryption and secret sharing. In order to protect users＇ sensitive data, our scheme allows users to customize access policies of their data and then outsource encrypted data to the OSNs service provider. Our scheme presents a multiparty access control model, which enables the disseminator to update the access policy of ciphertext if their attributes satisfy the existing access policy. Further, we present a partial decryption construction in which the computation overhead of user is largely reduced by delegating most of the decryption operations to the OSNs service provider. We also provide checkability on the results returned from the OSNs service provider to guarantee the correctness of partial decrypted ciphertext. Moreover, our scheme presents an efficient attribute revocation method that achieves both forward and backward secrecy. The security and performance analysis results indicate that the proposed scheme is secure and efficient in OSNs.展开更多
Named Data Networking(NDN)improves the data delivery efficiency by caching contents in routers. To prevent corrupted and faked contents be spread in the network,NDN routers should verify the digital signature of each ...Named Data Networking(NDN)improves the data delivery efficiency by caching contents in routers. To prevent corrupted and faked contents be spread in the network,NDN routers should verify the digital signature of each published content. Since the verification scheme in NDN applies the asymmetric encryption algorithm to sign contents,the content verification overhead is too high to satisfy wire-speed packet forwarding. In this paper, we propose two schemes to improve the verification performance of NDN routers to prevent content poisoning. The first content verification scheme, called "user-assisted",leads to the best performance, but can be bypassed if the clients and the content producer collude. A second scheme, named ``RouterCooperation ‘', prevents the aforementioned collusion attack by making edge routers verify the contents independently without the assistance of users and the core routers no longer verify the contents. The Router-Cooperation verification scheme reduces the computing complexity of cryptographic operation by replacing the asymmetric encryption algorithm with symmetric encryption algorithm.The simulation results demonstrate that this Router-Cooperation scheme can speed up18.85 times of the original content verification scheme with merely extra 80 Bytes transmission overhead.展开更多
A Data Acquisition System （DAQ） for electron energy loss coincident spectrometers （EELCS） has been developed. The system is composed of a Multiplex Time-Digital Converter （TDC） that measures the flying time of p...A Data Acquisition System （DAQ） for electron energy loss coincident spectrometers （EELCS） has been developed. The system is composed of a Multiplex Time-Digital Converter （TDC） that measures the flying time of positive and negative ions and a one-dimension positionsensitive detector that records the energy loss of scattering electrons. The experimental data are buffered in a first-in-first-out（FIFO） memory module, then transferred from the FIFO memory to PC by the USB interface. The DAQ system can record the flying time of several ions in one collision, and allows of different data collection modes. The system has been demonstrated at the Electron Energy Loss Coincident Spectrometers at the Laboratory of Atomic and Molecular Physics, USTC. A detail description of the whole system is given and experimental results shown.展开更多
Reversible data hiding techniques are capable of reconstructing the original cover image from stego-images. Recently, many researchers have focused on reversible data hiding to protect intellectual property rights. In...Reversible data hiding techniques are capable of reconstructing the original cover image from stego-images. Recently, many researchers have focused on reversible data hiding to protect intellectual property rights. In this paper, we combine reversible data hiding with the chaotic Henon map as an encryption technique to achieve an acceptable level of confidentiality in cloud computing environments. And, Haar digital wavelet transformation （HDWT） is also applied to convert an image from a spatial domain into a frequency domain. And then the decimal of coefficients and integer of high frequency band are modified for hiding secret bits. Finally, the modified coefficients are inversely transformed to stego-images.展开更多
In the analysis of big data,deep learn-ing is a crucial technique.Big data analysis tasks are typically carried out on the cloud since it offers strong computer capabilities and storage areas.Nev-ertheless,there is a ...In the analysis of big data,deep learn-ing is a crucial technique.Big data analysis tasks are typically carried out on the cloud since it offers strong computer capabilities and storage areas.Nev-ertheless,there is a contradiction between the open nature of the cloud and the demand that data own-ers maintain their privacy.To use cloud resources for privacy-preserving data training,a viable method must be found.A privacy-preserving deep learning model(PPDLM)is suggested in this research to ad-dress this preserving issue.To preserve data privacy,we first encrypted the data using homomorphic en-cryption(HE)approach.Moreover,the deep learn-ing algorithm’s activation function—the sigmoid func-tion—uses the least-squares method to process non-addition and non-multiplication operations that are not allowed by homomorphic.Finally,experimental re-sults show that PPDLM has a significant effect on the protection of data privacy information.Compared with Non-Privacy Preserving Deep Learning Model(NPPDLM),PPDLM has higher computational effi-ciency.展开更多
This paper describes a data transmission method using a cyclic redundancy check and inaudible frequencies.The proposed method uses inaudible high frequencies from 18 k Hz to 22 k Hz generated via the inner speaker of ...This paper describes a data transmission method using a cyclic redundancy check and inaudible frequencies.The proposed method uses inaudible high frequencies from 18 k Hz to 22 k Hz generated via the inner speaker of smart devices.Using the proposed method,the performance is evaluated by conducting data transmission tests between a smart book and smart phone.The test results confirm that the proposed method can send 32 bits of data in an average of 235 ms,the transmission success rate reaches 99.47%,and the error detection rate of the cyclic redundancy check is0.53%.展开更多
Among different heavy liquid metals(HLMs), lead-bismuth eutectic(LBE) is considered at present as a potential candidate for the coolant of new generation fast reactors(critical and subcritical) and for liquid spallati...Among different heavy liquid metals(HLMs), lead-bismuth eutectic(LBE) is considered at present as a potential candidate for the coolant of new generation fast reactors(critical and subcritical) and for liquid spallation neutron sources and accelerator driven systems(ADS). A high temperature liquid LBE loop, KYLIN-II-M,has been built to study the characteristics of corrosion and fluidity of LBE at the Institute of Nuclear Energy Safety Technology. However, due to the sensors and execution components of the loop work at high temperatures and in severely corrosive environments, the reliability and security of the data acquisition and control system(DACS) of KYLIN-II-M face challenges during the loop operation. In order to meet the urgent needs for KYLIN-II-M's long-term stable operation, a virtualization and redundancy control system has been developed.The onsite operation result shows that the DACS is stable and reliable. In this paper, the experimental results are described in detail.展开更多
Despite the multifaceted advantages of cloud computing,concerns about data leakage or abuse impedes its adoption for security-sensi tive tasks.Recent investigations have revealed that the risk of unauthorized data acc...Despite the multifaceted advantages of cloud computing,concerns about data leakage or abuse impedes its adoption for security-sensi tive tasks.Recent investigations have revealed that the risk of unauthorized data access is one of the biggest concerns of users of cloud-based services.Transparency and accountability for data managed in the cloud is necessary.Specifically,when using a cloudhost service,a user typically has to trust both the cloud service provider and cloud infrastructure provider to properly handling private data.This is a multi-party system.Three particular trust models can be used according to the credibility of these providers.This pa per describes techniques for preventing data leakage that can be used with these different models.展开更多
针对大多数加密流量分类(encrypted traffic classification,ETC)模型由于标签数据稀缺而导致的性能下降问题,提出了一个基于对比学习的半监督加密流量分类(semisupervised encrypted traffic classification based on contrastive lear...针对大多数加密流量分类(encrypted traffic classification,ETC)模型由于标签数据稀缺而导致的性能下降问题,提出了一个基于对比学习的半监督加密流量分类(semisupervised encrypted traffic classification based on contrastive learning,SSETC-CL)模型。通过比较样本之间的相似性和差异性,SSETC-CL模型能够从大量无标注数据中学习到有用的表示,从而获得一个通用且优秀的特征编码网络,降低了下游任务对标签数据的依赖。本文在公有数据集ISCXVPN2016以及两个自采数据集上对SSETC-CL模型进行了评估。与其他基准模型相比,SSETC-CL模型在设定任务上的表现最佳,准确率最大提升了8.92%。实验结果表明,SSETC-CL模型不仅在预训练模型已知的流量上具有较高的精度,而且具备将预训练模型所获得的知识应用于未知流量的迁移能力。展开更多
基金partially supported by the National Natural Science Foundation of China under grant no.62372245the Foundation of Yunnan Key Laboratory of Blockchain Application Technology under Grant 202105AG070005+1 种基金in part by the Foundation of State Key Laboratory of Public Big Datain part by the Foundation of Key Laboratory of Computational Science and Application of Hainan Province under Grant JSKX202202。
文摘For the goals of security and privacy preservation,we propose a blind batch encryption-and public ledger-based data sharing protocol that allows the integrity of sensitive data to be audited by a public ledger and allows privacy information to be preserved.Data owners can tightly manage their data with efficient revocation and only grant one-time adaptive access for the fulfillment of the requester.We prove that our protocol is semanticallly secure,blind,and secure against oblivious requesters and malicious file keepers.We also provide security analysis in the context of four typical attacks.
文摘To enhance the security of user data in the clouds,we present an adaptive and dynamic data encryption method to encrypt user data in the mobile phone before it is uploaded.Firstly,the adopted data encryption algorithm is not static and uniform.For each encryption,this algorithm is adaptively and dynamically selected from the algorithm set in the mobile phone encryption system.From the mobile phone's character,the detail encryption algorithm selection strategy is confirmed based on the user's mobile phone hardware information,personalization information and a pseudo-random number.Secondly,the data is rearranged with a randomly selected start position in the data before being encrypted.The start position's randomness makes the mobile phone data encryption safer.Thirdly,the rearranged data is encrypted by the selected algorithm and generated key.Finally,the analysis shows this method possesses the higher security because the more dynamics and randomness are adaptively added into the encryption process.
基金supported by the National Key Research and Development Plan in China(Grant No.2020YFB1005500)。
文摘With increasing demand for data circulation,ensuring data security and privacy is paramount,specifically protecting privacy while maximizing utility.Blockchain,while decentralized and transparent,faces challenges in privacy protection and data verification,especially for sensitive data.Existing schemes often suffer from inefficiency and high overhead.We propose a privacy protection scheme using BGV homomorphic encryption and Pedersen Secret Sharing.This scheme enables secure computation on encrypted data,with Pedersen sharding and verifying the private key,ensuring data consistency and immutability.The blockchain framework manages key shards,verifies secrets,and aids security auditing.This approach allows for trusted computation without revealing the underlying data.Preliminary results demonstrate the scheme's feasibility in ensuring data privacy and security,making data available but not visible.This study provides an effective solution for data sharing and privacy protection in blockchain applications.
基金sponsored by the National Natural Science Foundation of China under grant number No. 62172353, No. 62302114, No. U20B2046 and No. 62172115Innovation Fund Program of the Engineering Research Center for Integration and Application of Digital Learning Technology of Ministry of Education No.1331007 and No. 1311022+1 种基金Natural Science Foundation of the Jiangsu Higher Education Institutions Grant No. 17KJB520044Six Talent Peaks Project in Jiangsu Province No.XYDXX-108
文摘With the rapid development of information technology,IoT devices play a huge role in physiological health data detection.The exponential growth of medical data requires us to reasonably allocate storage space for cloud servers and edge nodes.The storage capacity of edge nodes close to users is limited.We should store hotspot data in edge nodes as much as possible,so as to ensure response timeliness and access hit rate;However,the current scheme cannot guarantee that every sub-message in a complete data stored by the edge node meets the requirements of hot data;How to complete the detection and deletion of redundant data in edge nodes under the premise of protecting user privacy and data dynamic integrity has become a challenging problem.Our paper proposes a redundant data detection method that meets the privacy protection requirements.By scanning the cipher text,it is determined whether each sub-message of the data in the edge node meets the requirements of the hot data.It has the same effect as zero-knowledge proof,and it will not reveal the privacy of users.In addition,for redundant sub-data that does not meet the requirements of hot data,our paper proposes a redundant data deletion scheme that meets the dynamic integrity of the data.We use Content Extraction Signature(CES)to generate the remaining hot data signature after the redundant data is deleted.The feasibility of the scheme is proved through safety analysis and efficiency analysis.
基金The research work was supported by the National Key Research and Development Plan in China(Grant No.2020YFB1005500)Key Project Plan of Blockchain in Ministry of Education of the People’s Republic of China(Grant No.2020KJ010802)Natural Science Foundation of Beijing Municipality(Grant No.M21034).
文摘With the in-depth application of new technologies such as big data in education fields,the storage and sharing model of student education records data still faces many challenges in terms of privacy protection and efficient transmission.In this paper,we propose a data security storage and sharing scheme based on consortium blockchain,which is a credible search scheme without verification.In our scheme,the implementation of data security storage is using the blockchain and storage server together.In detail,the smart contract provides protection for data keywords,the storage server stores data after data masking,and the blockchain ensures the traceability of query transactions.The need for precise privacy data is achieved by constructing a dictionary.Cryptographic techniques such as AES and RSA are used for encrypted storage of data,keywords,and digital signatures.Security analysis and performance evaluation shows that the availability,high efficiency,and privacy-preserving can be achieved.Meanwhile,this scheme has better robustness compared to other educational records data sharing models.
基金This research was supported by a grant[KCG-01-2017-01]through the Disaster and Safety Management Institute funded by the Ministry of Public Safety and Securitythe National Research Foundation of Korea(NRF)grant[No.2018R1D1A1B07050208]funded by the Ministry of Science and ICT of Korea Government.
文摘This study developed a new methodology for analyzing the risk level of marine spill accidents from two perspectives,namely,marine traffic density and sensitive resources.Through a case study conducted in Busan,South Korea,detailed procedures of the methodology were proposed and its scalability was confirmed.To analyze the risk from a more detailed and microscopic viewpoint,vessel routes as hazard sources were delineated on the basis of automated identification system(AIS)big data.The outliers and errors of AIS big data were removed using the density-based spatial clustering of applications with noise algorithm,and a marine traffic density map was evaluated by combining all of the gridded routes.Vulnerability of marine environment was identified on the basis of the sensitive resource map constructed by the Korea Coast Guard in a similar manner to the National Oceanic and Atmospheric Administration environmental sensitivity index approach.In this study,aquaculture sites,water intake facilities of power plants,and beach/resort areas were selected as representative indicators for each category.The vulnerability values of neighboring cells decreased according to the Euclidean distance from the resource cells.Two resulting maps were aggregated to construct a final sensitive resource and traffic density(SRTD)risk analysis map of the Busan–Ulsan sea areas.We confirmed the effectiveness of SRTD risk analysis by comparing it with the actual marine spill accident records.Results show that all of the marine spill accidents in 2018 occurred within 2 km of high-risk cells(level 6 and above).Thus,if accident management and monitoring capabilities are concentrated on high-risk cells,which account for only 6.45%of the total study area,then it is expected that it will be possible to cope with most marine spill accidents effectively.
基金Project supported by the International Collaborative Research Project of Qilu University of Technology (Grant No.QLUTGJHZ2018020)the Project of Youth Innovation and Technology Support Plan for Colleges and Universities in Shandong Province,China (Grant No.2021KJ025)the Major Scientific and Technological Innovation Projects of Shandong Province,China (Grant Nos.2019JZZY010731 and 2020CXGC010901)。
文摘With the development of smart grid, operation and control of a power system can be realized through the power communication network, especially the power production and enterprise management business involve a large amount of sensitive information, and the requirements for data security and real-time transmission are gradually improved. In this paper, a new 9-dimensional(9D) complex chaotic system with quaternion is proposed for the encryption of smart grid data. Firstly, we present the mathematical model of the system, and analyze its attractors, bifurcation diagram, complexity,and 0–1 test. Secondly, the pseudo-random sequences are generated by the new chaotic system to encrypt power data.Finally, the proposed encryption algorithm is verified with power data and images in the smart grid, which can ensure the encryption security and real time. The verification results show that the proposed encryption scheme is technically feasible and available for power data and image encryption in smart grid.
基金the support of the National High Technology Research and Development Program of China (863) (Grant No. 2012AA1406)
文摘In direct sequence spread spectrum communication both for satelliteto-ground and inter-satellite links, the system constrains due to radio frequency spectral occupation, channel data throughput and link performances in terms of data channel coding which might result in a signal structure where the symbol duration is shorter than the pseudo code period. This can generate some difficulties in the DSSS signal acquisition due to the polarity inversion caused by the data modulation. To eliminate the influence due to polarity inversion, this paper proposes a novel acquisition algorithm based on the simultaneous search of the code phase, data phase and Doppler frequency. In the proposed algorithm the data phase is predicted and the correlation period for the coherent integration can be set equal to the symbol duration. Then non-coherent accumulation over different symbol is implemented in order to enhance the acquisition algorithm sensitivity; the interval of non-coherent accumulation is the least common multiple between the symbol duration and the pseudo code period. The algorithm proposed can largely minimize the SNR loss caused by data polarity inversion and enhance acquisition performance without a noticeable increase in hardware complexity. Theoretical analysis, simulation and measured results verify the validity of the algorithm.
基金This work has been supported by the National Natural Science Foundation of China under Grant No.61272519,the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.20120005110017,and the National Key Technology R&D Program under Grant No.2012BAH06B02
文摘Despite that existing data sharing systems in online social networks （OSNs） propose to encrypt data before sharing, the multiparty access control of encrypted data has become a challenging issue. In this paper, we propose a secure data sharing scheme in 0SNs based on ciphertext-policy attribute- based proxy re-encryption and secret sharing. In order to protect users＇ sensitive data, our scheme allows users to customize access policies of their data and then outsource encrypted data to the OSNs service provider. Our scheme presents a multiparty access control model, which enables the disseminator to update the access policy of ciphertext if their attributes satisfy the existing access policy. Further, we present a partial decryption construction in which the computation overhead of user is largely reduced by delegating most of the decryption operations to the OSNs service provider. We also provide checkability on the results returned from the OSNs service provider to guarantee the correctness of partial decrypted ciphertext. Moreover, our scheme presents an efficient attribute revocation method that achieves both forward and backward secrecy. The security and performance analysis results indicate that the proposed scheme is secure and efficient in OSNs.
基金financially supported by Shenzhen Key Fundamental Research Projects(Grant No.:JCYJ20170306091556329).
文摘Named Data Networking(NDN)improves the data delivery efficiency by caching contents in routers. To prevent corrupted and faked contents be spread in the network,NDN routers should verify the digital signature of each published content. Since the verification scheme in NDN applies the asymmetric encryption algorithm to sign contents,the content verification overhead is too high to satisfy wire-speed packet forwarding. In this paper, we propose two schemes to improve the verification performance of NDN routers to prevent content poisoning. The first content verification scheme, called "user-assisted",leads to the best performance, but can be bypassed if the clients and the content producer collude. A second scheme, named ``RouterCooperation ‘', prevents the aforementioned collusion attack by making edge routers verify the contents independently without the assistance of users and the core routers no longer verify the contents. The Router-Cooperation verification scheme reduces the computing complexity of cryptographic operation by replacing the asymmetric encryption algorithm with symmetric encryption algorithm.The simulation results demonstrate that this Router-Cooperation scheme can speed up18.85 times of the original content verification scheme with merely extra 80 Bytes transmission overhead.
基金National Natural Science Foundation of China (Nos. 10134010 and 10004010)
文摘A Data Acquisition System （DAQ） for electron energy loss coincident spectrometers （EELCS） has been developed. The system is composed of a Multiplex Time-Digital Converter （TDC） that measures the flying time of positive and negative ions and a one-dimension positionsensitive detector that records the energy loss of scattering electrons. The experimental data are buffered in a first-in-first-out（FIFO） memory module, then transferred from the FIFO memory to PC by the USB interface. The DAQ system can record the flying time of several ions in one collision, and allows of different data collection modes. The system has been demonstrated at the Electron Energy Loss Coincident Spectrometers at the Laboratory of Atomic and Molecular Physics, USTC. A detail description of the whole system is given and experimental results shown.
文摘Reversible data hiding techniques are capable of reconstructing the original cover image from stego-images. Recently, many researchers have focused on reversible data hiding to protect intellectual property rights. In this paper, we combine reversible data hiding with the chaotic Henon map as an encryption technique to achieve an acceptable level of confidentiality in cloud computing environments. And, Haar digital wavelet transformation （HDWT） is also applied to convert an image from a spatial domain into a frequency domain. And then the decimal of coefficients and integer of high frequency band are modified for hiding secret bits. Finally, the modified coefficients are inversely transformed to stego-images.
基金This work was partially supported by the Natural Science Foundation of Beijing Municipality(No.4222038)by Open Research Project of the State Key Laboratory of Media Convergence and Communication(Communication University of China),the National Key R&D Program of China(No.2021YFF0307600)Fundamental Research Funds for the Central Universities.
文摘In the analysis of big data,deep learn-ing is a crucial technique.Big data analysis tasks are typically carried out on the cloud since it offers strong computer capabilities and storage areas.Nev-ertheless,there is a contradiction between the open nature of the cloud and the demand that data own-ers maintain their privacy.To use cloud resources for privacy-preserving data training,a viable method must be found.A privacy-preserving deep learning model(PPDLM)is suggested in this research to ad-dress this preserving issue.To preserve data privacy,we first encrypted the data using homomorphic en-cryption(HE)approach.Moreover,the deep learn-ing algorithm’s activation function—the sigmoid func-tion—uses the least-squares method to process non-addition and non-multiplication operations that are not allowed by homomorphic.Finally,experimental re-sults show that PPDLM has a significant effect on the protection of data privacy information.Compared with Non-Privacy Preserving Deep Learning Model(NPPDLM),PPDLM has higher computational effi-ciency.
基金supported by Ministry of Educationunder Basic Science Research Program under Grant No.NRF-2013R1A1A2061478
文摘This paper describes a data transmission method using a cyclic redundancy check and inaudible frequencies.The proposed method uses inaudible high frequencies from 18 k Hz to 22 k Hz generated via the inner speaker of smart devices.Using the proposed method,the performance is evaluated by conducting data transmission tests between a smart book and smart phone.The test results confirm that the proposed method can send 32 bits of data in an average of 235 ms,the transmission success rate reaches 99.47%,and the error detection rate of the cyclic redundancy check is0.53%.
基金Supported by the Accelerator Driven Systems Project of the Chinese Academy of Sciences(No.XDA03040000)
文摘Among different heavy liquid metals(HLMs), lead-bismuth eutectic(LBE) is considered at present as a potential candidate for the coolant of new generation fast reactors(critical and subcritical) and for liquid spallation neutron sources and accelerator driven systems(ADS). A high temperature liquid LBE loop, KYLIN-II-M,has been built to study the characteristics of corrosion and fluidity of LBE at the Institute of Nuclear Energy Safety Technology. However, due to the sensors and execution components of the loop work at high temperatures and in severely corrosive environments, the reliability and security of the data acquisition and control system(DACS) of KYLIN-II-M face challenges during the loop operation. In order to meet the urgent needs for KYLIN-II-M's long-term stable operation, a virtualization and redundancy control system has been developed.The onsite operation result shows that the DACS is stable and reliable. In this paper, the experimental results are described in detail.
基金supported by National Basic Research (973) Program of China (2011CB302505)Natural Science Foundation of China (61373145, 61170210)+1 种基金National High-Tech R&D (863) Program of China (2012AA012600,2011AA01A203)Chinese Special Project of Science and Technology (2012ZX01039001)
文摘Despite the multifaceted advantages of cloud computing,concerns about data leakage or abuse impedes its adoption for security-sensi tive tasks.Recent investigations have revealed that the risk of unauthorized data access is one of the biggest concerns of users of cloud-based services.Transparency and accountability for data managed in the cloud is necessary.Specifically,when using a cloudhost service,a user typically has to trust both the cloud service provider and cloud infrastructure provider to properly handling private data.This is a multi-party system.Three particular trust models can be used according to the credibility of these providers.This pa per describes techniques for preventing data leakage that can be used with these different models.
文摘针对大多数加密流量分类(encrypted traffic classification,ETC)模型由于标签数据稀缺而导致的性能下降问题,提出了一个基于对比学习的半监督加密流量分类(semisupervised encrypted traffic classification based on contrastive learning,SSETC-CL)模型。通过比较样本之间的相似性和差异性,SSETC-CL模型能够从大量无标注数据中学习到有用的表示,从而获得一个通用且优秀的特征编码网络,降低了下游任务对标签数据的依赖。本文在公有数据集ISCXVPN2016以及两个自采数据集上对SSETC-CL模型进行了评估。与其他基准模型相比,SSETC-CL模型在设定任务上的表现最佳,准确率最大提升了8.92%。实验结果表明,SSETC-CL模型不仅在预训练模型已知的流量上具有较高的精度,而且具备将预训练模型所获得的知识应用于未知流量的迁移能力。
