Group Signature Based on Non-interactive Zero-Knowledge Proofs

Non-Interactive Zero-Knowledge(NIZK for short) proofs are fascinating and extremely useful in many security protocols. In this paper,a new group signature scheme,decisional linear assumption group signature(DLAGS for short) with NIZK proofs is proposed which can prove and sign the multiple values rather than individual bits based on DLIN assumption. DLAGS does not need to interact between the verifier and issuer,which can decrease the communication times and storage cost compared with the existing interactive group signature schemes. We prove and sign the blocks of messages instead of limiting the proved message to only one bit(0 or 1) in the conventional non-interactive zero-knowledge proof system,and we also prove that our scheme satisfy the property of anonymity,unlinkability and traceability. Finally,our scheme is compared with the other scheme(Benoitt's scheme) which is also based on the NIZK proofs system and the DLIN assumption,and the results show that our scheme requires fewer members of groups and computational times.

Block Verification Mechanism Based on Zero-Knowledge Proof in Blockchain

Since transactions in blockchain are based on public ledger verification,this raises security concerns about privacy protection.And it will cause the accumulation of data on the chain and resulting in the low efficiency of block verification,when the whole transaction on the chain is verified.In order to improve the efficiency and privacy protection of block data verification,this paper proposes an efficient block verification mechanism with privacy protection based on zeroknowledge proof(ZKP),which not only protects the privacy of users but also improves the speed of data block verification.There is no need to put the whole transaction on the chain when verifying block data.It just needs to generate the ZKP and root hash with the transaction information,then save them to the smart contract for verification.Moreover,the ZKP verification in smart contract is carried out to realize the privacy protection of the transaction and efficient verification of the block.When the data is validated,the buffer accepts the complete transaction,updates the transaction status in the cloud database,and packages up the chain.So,the ZKP strengthens the privacy protection ability of blockchain,and the smart contracts save the time cost of block verification.

Privacy-preserving analytics for the securitization market: a zero-knowledge distributed ledger technology application

A zero-knowledge proof or protocol is a cryptographic technique for verifying private data without revealing it in its clear form.In this paper,we evaluate the potential for zero-knowledge distributed ledger technology to alleviate asymmetry of information in the asset-backed securitization market.To frame this inquiry,we conducted market data analyses,a review of prior literature,stakeholder interviews with investors,originators and security issuers and collaboration with blockchain engineers and researchers.We introduce a new system which could enable all market participants in the securitization lifecycle(e.g.investors,rating agencies,regulators and security issuers)to interact on a unique decentralized platform while maintaining the privacy of loan-level data,therefore providing the industry with timely analytics and performance data.Our platform is powered by zkLedger(Narula et al.2018),a zero-knowledge protocol developed by the MIT Media Lab and the first system that enables participants of a distributed ledger to run publicly verifiable analytics on masked data.

Simplified Design for Concurrent Statistical Zero-Knowledge Arguments

This paper shows that the protocol presented by Goyal et al. can be further simplified for a one-way function, with the simplified protocol being more practical for the decisional Diffie-Hellman assumption. Goyal et al. provided a general transformation from any honest verifier statistical zero-knowledge argument to a concurrent statistical zero-knowledge argument. Their transformation relies only on the existence of one-way functions. For the simplified transformation, the witness indistinguishable proof of knowledge protocols in ＂parallel＂ not only plays the role of preamble but also removes some computational zero-knowledge proofs, which Goyal et al. used to prove the existence of the valid openings to the commitments. Therefore, although some computational zero-knowledge proofs are replaced with a weaker notion, the witness indistinguishable protocol, the proof of soundness can still go through.

A Blockchain-Based Proxy Re-Encryption Scheme with Conditional Privacy Protection and Auditability

With the development of Internet of Things technology,intelligent door lock devices are widely used in the field of house leasing.In the traditional housing leasing scenario,problems of door lock information disclosure,tenant privacy disclosure and rental contract disputes frequently occur,and the security,fairness and auditability of the housing leasing transaction cannot be guaranteed.To solve the above problems,a blockchain-based proxy re-encryption scheme with conditional privacy protection and auditability is proposed.The scheme implements fine-grained access control of door lock data based on attribute encryption technology with policy hiding,and uses proxy re-encryption technology to achieve auditable supervision of door lock information transactions.Homomorphic encryption technology and zero-knowledge proof technology are introduced to ensure the confidentiality of housing rent information and the fairness of rent payment.To construct a decentralized housing lease transaction architecture,the scheme realizes the efficient collaboration between the door lock data ciphertext stored under the chain and the key information ciphertext on the chain based on the blockchain and InterPlanetary File System.Finally,the security proof and computing performance analysis of the proposed scheme are carried out.The results show that the scheme can resist the chosen plaintext attack and has low computational cost.

A Cloud-Fog Enabled and Privacy-Preserving IoT Data Market Platform Based on Blockchain

The dynamic landscape of the Internet of Things(IoT)is set to revolutionize the pace of interaction among entities,ushering in a proliferation of applications characterized by heightened quality and diversity.Among the pivotal applications within the realm of IoT,as a significant example,the Smart Grid(SG)evolves into intricate networks of energy deployment marked by data integration.This evolution concurrently entails data interchange with other IoT entities.However,there are also several challenges including data-sharing overheads and the intricate establishment of trusted centers in the IoT ecosystem.In this paper,we introduce a hierarchical secure data-sharing platform empowered by cloud-fog integration.Furthermore,we propose a novel non-interactive zero-knowledge proof-based group authentication and key agreement protocol that supports one-to-many sharing sets of IoT data,especially SG data.The security formal verification tool shows that the proposed scheme can achieve mutual authentication and secure data sharing while protecting the privacy of data providers.Compared with previous IoT data sharing schemes,the proposed scheme has advantages in both computational and transmission efficiency,and has more superiority with the increasing volume of shared data or increasing number of participants.

A Blockchain-Based Efficient Cross-Domain Authentication Scheme for Internet of Vehicles

The Internet of Vehicles(IoV)is extensively deployed in outdoor and open environments to effectively address traffic efficiency and safety issues by connecting vehicles to the network.However,due to the open and variable nature of its network topology,vehicles frequently engage in cross-domain interactions.During such processes,directly uploading sensitive information to roadside units for interaction may expose it to malicious tampering or interception by attackers,thus compromising the security of the cross-domain authentication process.Additionally,IoV imposes high real-time requirements,and existing cross-domain authentication schemes for IoV often encounter efficiency issues.To mitigate these challenges,we propose CAIoV,a blockchain-based efficient cross-domain authentication scheme for IoV.This scheme comprehensively integrates technologies such as zero-knowledge proofs,smart contracts,and Merkle hash tree structures.It divides the cross-domain process into anonymous cross-domain authentication and safe cross-domain authentication phases to ensure efficiency while maintaining a balance between efficiency and security.Finally,we evaluate the performance of CAIoV.Experimental results demonstrate that our proposed scheme reduces computational overhead by approximately 20%,communication overhead by around 10%,and storage overhead by nearly 30%.

A Fair and Trusted Trading Scheme for Medical Data Based on Smart Contracts

Data is regarded as a valuable asset,and sharing data is a prerequisite for fully exploiting the value of data.However,the current medical data sharing scheme lacks a fair incentive mechanism,and the authenticity of data cannot be guaranteed,resulting in low enthusiasm of participants.A fair and trusted medical data trading scheme based on smart contracts is proposed,which aims to encourage participants to be honest and improve their enthusiasm for participation.The scheme uses zero-knowledge range proof for trusted verification,verifies the authenticity of the patient’s data and the specific attributes of the data before the transaction,and realizes privacy protection.At the same time,the game pricing strategy selects the best revenue strategy for all parties involved and realizes the fairness and incentive of the transaction price.The smart contract is used to complete the verification and game bargaining process,and the blockchain is used as a distributed ledger to record the medical data transaction process to prevent data tampering and transaction denial.Finally,by deploying smart contracts on the Ethereum test network and conducting experiments and theoretical calculations,it is proved that the transaction scheme achieves trusted verification and fair bargaining while ensuring privacy protection in a decentralized environment.The experimental results show that the model improves the credibility and fairness of medical data transactions,maximizes social benefits,encourages more patients and medical institutions to participate in the circulation of medical data,and more fully taps the potential value of medical data.

Existence of 3-round zero-knowledge proof systems for NP

This paper considers the existence of 3-round zero-knowledge proof systems for NP. Whether there exist 3-round non-black-box zero-knowledge proof systems for NP language is an open problem. By introducing a new interactive proof model, we construct a 3-round zero-knowledge proof system for graph 3-coloring under standard assumptions. Our protocol is a non-black-box zero-knowledge proof because we adopt a special strategy to prove the zero-knowledge property. Consequently, our construction shows the existence of 3-round non-black-box zero-knowledge proof for all languages in NP under the DDH assumption.

Memorizable Interactive Proof and Zero-Knowledge Proof Systems

Interactive proof and zero-knowledge proof systems are two important concepts in cryptography and complexity theory. In the past two decades, a great number of interactive proof and zero-knowledge proof protocols have been designed and applied in practice. In this paper, a simple memorizable zero-knowledge protocol is proposed for graph non-isomorphism problem, based on the memorizable interactive proof system, which is extended from the original definition of interactive proof and is more applicable in reality. Keywords interactive proof - zero-knowledge proof - memorizable interactive proof - memorizable zero-knowledge proof This work was supported by the ministry of Science and Technology of China (Grant No.2001CCA03000), and the National Natural Science Foundation of China (Grant No.60273045).Ning Chen received his B.S. degree from Fudan University in 2001. Now he is a master candidate of Department of Computer Science, Fudan University. His research interests include computational complexity, computational cryptography, algorithm design and analysis.Jia-Wei Rong received her B.S. degree from Fudan University in 2002. Now she is a master candidate of Department of Computer Science, Fudan University. Her research interests include computational cryptography, machine learning, artificial intelligence.

钻井井喷爆炸事故分析及对策

针对井喷爆炸事故造成的巨大经济和环境问题,从消除井场点火源出发,讨论了井喷发生后防止爆炸的问题。基于井喷爆炸事故统计信息,利用事故树法,分析了井场可能存在的点火源,在此基础上提出井场防止井喷爆炸的措施。分析发现井喷爆炸主要分布在井喷后小于5分钟和井喷后大于1小时时间段,点火源主要为井场存在的点火源和后续抢救工作时带入的点火源;井场点火源主要分为明火、电火花、撞击火花和静电火花,通过井喷爆炸事故统计分析,电火花和撞击火花同样应该引起重视。

一种实用的可验证秘密共享方案

在秘密共享方案中,如果庄家选择的多项式f(x)=∑r-1i=0aixi含有零系数项,也就是某些ai=0,那么不诚实的庄家有可能构造一个门限为t'(<t)的秘密共享方案。文章构造了怎样证明f(x)是一个不包含零项多项式的统计零知识证明系统,并基于这个系统和Pedersen的可验证秘密共享方案,提出了一个在信息理论意义上安全的能够防止庄家构造门限为t'的可验证秘密共享方案。

隔声装置的隔声特性预测设计技术

隔声装置被广泛应用于船舶动力机械的空气噪声控制.采用统计能量分析法来预测简单隔声装置的隔声特性,并将预测结果与试验结果进行比较,发现两者吻合良好.在此基础上,进一步研究了吸声材料和阻尼对隔声装置声学性能的影响.结果表明,吸声材料可以有效改善隔声装置中高频的隔声性能;阻尼可以大幅提高吻合频率处的隔声性能,而对其他频率范围的隔声性能提高贡献较弱.

赢多输少还是输多赢少?——WTO争端解决机制申诉方败诉案件解析

利用WTO争端解决机制处理的国际贸易纠纷中申诉方完全败诉的案件占专家组处理案件的10%强,主要原因是申诉方未能完成举证义务,申诉方没有正确提出诉请,被申诉方政府的声明使得专家组不支持诉请。

对一种多重密钥共享认证改进方案的完善

通过分析一种多重密钥共享认证改进方案,指出其中存在的漏洞和防止成员欺骗中存在的问题,提出了自己的完善方案,使其在共享多个密钥、子密钥可以重复使用、防止管理者欺骗及参与成员欺骗等方面更加完善.

高可靠度的安全撞击强度公式

针对现有的临界落高测定方法存在的估计精度差、可信程度低的缺点， 建立了高置信度、高可靠度的安全撞击强度公式。该公式可以综合利用当前试验数据和以往积累的试验数据确定安全撞击强度， 从而既提高了估计精度又减少了试验费用。大量Ｍｏｎｔｅ Ｃａｒｌｏ 仿真分析表明，该式不仅可以在小样本条件下确定安全撞击强度， 而且置信度高。

概率论与数理统计思想的应用

对偶然性的认识,是一个现代人知识结构中应具备的成分.本文就概率论与数理统计的方法与思想,在解决代数、数学分析学科中的一些问题及在现代金融理论和日常生活中的应用展开一些讨论,从中可以看出概率方法与数理统计的思想在解决问题中的高效性、简捷性和实用性.

用统计分析法估算复合材料的防弹性能

探讨了纤维增强树脂基复合材料的防弹机理，并用统计方法建立了复合材料弹道极限速度Ｖ_（５０）的理论估算公式。

保证试验后钙钠玻璃的循环疲劳强度及寿命

研究了保证试验对钙钠玻璃的循环疲劳强度及寿命的影响。在实际操作条件下，保证试验过程中试件中会发生亚临界裂纹扩展，因而对试件造成损伤。对试件的寿命估算和强度分析中需考虑这种损伤的影响。材料的亚临界裂纹扩展参量（Ｖｃ、ｎ）和保证试验中的卸载速率对保证试验的效果有极为重要的影响。选择高卸载速率和惰性试验环境可提高保证试验后陶瓷构件的最小强度。保证试验的最佳σｐ值可根据实用卸载速率和材料的亚临界裂纹扩展参量确定。只要保证试验后构件最小强度较高，保证试验后陶瓷构件在高存活率下的疲劳强度与寿命都会得到提高。

关于馆藏文献的评价──文献资源建设理论与实践研讨之三

馆藏文献的评价是对馆藏文献体系的各方面属性进行检测，做出评判，为图书馆控制文献资源建设过程、进行下一步科学决策提供依据。馆藏文献评价的标准有二：一是文献标准，一是用户标准。评价现代图书馆馆藏文献应采用“用户标准”。评价主要从文献数量、情报含量、结构和利用情况四方面进行。评价的方法有定性的、定量的好些种。地方大学图书馆应根据需要，选用适合本馆的方法，进行馆藏文献的评价工作。