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1.
In the digital era, electronic medical record (EMR) has been a major way for hospitals to store patients’ medical data. The traditional centralized medical system and semi-trusted cloud storage are difficult to achieve dynamic balance between privacy protection and data sharing. The storage capacity of blockchain is limited and single blockchain schemes have poor scalability and low throughput. To address these issues, we propose a secure and efficient medical data storage and sharing scheme based on double blockchain. In our scheme, we encrypt the original EMR and store it in the cloud. The storage blockchain stores the index of the complete EMR, and the shared blockchain stores the index of the shared part of the EMR. Users with different attributes can make requests to different blockchains to share different parts according to their own permissions. Through experiments, it was found that cloud storage combined with blockchain not only solved the problem of limited storage capacity of blockchain, but also greatly reduced the risk of leakage of the original EMR. Content Extraction Signature (CES) combined with the double blockchain technology realized the separation of the privacy part and the shared part of the original EMR. The symmetric encryption technology combined with Ciphertext-Policy Attribute-Based Encryption (CP–ABE) not only ensures the safe storage of data in the cloud, but also achieves the consistency and convenience of data update, avoiding redundant backup of data. Safety analysis and performance analysis verified the feasibility and effectiveness of our scheme.  相似文献   

2.
Distributed storage can store data in multiple devices or servers to improve data security. However, in today's explosive growth of network data, traditional distributed storage scheme is faced with some severe challenges such as insufficient performance, data tampering, and data lose. A distributed storage scheme based on blockchain has been proposed to improve security and efficiency of traditional distributed storage. Under this scheme, the following improvements have been made in this paper. This paper first analyzes the problems faced by distributed storage. Then proposed to build a new distributed storage blockchain scheme with sharding blockchain. The proposed scheme realizes the partitioning of the network and nodes by means of blockchain sharding technology, which can improve the efficiency of data verification between nodes. In addition, this paper uses polynomial commitment to construct a new verifiable secret share scheme called PolyVSS. This new scheme is one of the foundations for building our improved distributed storage blockchain scheme. Compared with the previous scheme, our new scheme does not require a trusted third party and has some new features such as homomorphic and batch opening. The security of VSS can be further improved. Experimental comparisons show that the proposed scheme significantly reduces storage and communication costs.  相似文献   

3.
As the number of sensor network application scenarios continues to grow, the security problems inherent in this approach have become obstacles that hinder its wide application. However, it has attracted increasing attention from industry and academia. The blockchain is based on a distributed network and has the characteristics of nontampering and traceability of block data. It is thus naturally able to solve the security problems of the sensor networks. Accordingly, this paper first analyzes the security risks associated with data storage in the sensor networks, then proposes using blockchain technology to ensure that data storage in the sensor networks is secure. In the traditional blockchain, the data layer uses a Merkle hash tree to store data; however, the Merkle hash tree cannot provide non-member proof, which makes it unable to resist the attacks of malicious nodes in networks. To solve this problem, this paper utilizes a cryptographic accumulator rather than a Merkle hash tree to provide both member proof and nonmember proof. Moreover, the number of elements in the existing accumulator is limited and unable to meet the blockchain’s expansion requirements. This paper therefore proposes a new type of unbounded accumulator and provides its definition and security model. Finally, this paper constructs an unbounded accumulator scheme using bilinear pairs and analyzes its performance.  相似文献   

4.
With the rapid development of information technology, the development of blockchain technology has also been deeply impacted. When performing block verification in the blockchain network, if all transactions are verified on the chain, this will cause the accumulation of data on the chain, resulting in data storage problems. At the same time, the security of data is also challenged, which will put enormous pressure on the block, resulting in extremely low communication efficiency of the block. The traditional blockchain system uses the Merkle Tree method to store data. While verifying the integrity and correctness of the data, the amount of proof is large, and it is impossible to verify the data in batches. A large amount of data proof will greatly impact the verification efficiency, which will cause end-to-end communication delays and seriously affect the blockchain system’s stability, efficiency, and security. In order to solve this problem, this paper proposes to replace the Merkle tree with polynomial commitments, which take advantage of the properties of polynomials to reduce the proof size and communication consumption. By realizing the ingenious use of aggregated proof and smart contracts, the verification efficiency of blocks is improved, and the pressure of node communication is reduced.  相似文献   

5.
目的 探究区块链技术在产品溯源和包装防伪上的应用现状,以期为区块链防伪溯源体系的研究和建立提供参考。方法 整理国内外文献,系统分析区块链技术的来源和发展,概述区块链技术在实现防伪溯源上的机理;然后总结在食品包装、电子存证和处方药溯源的相关应用研究。结果 相比传统的防伪和溯源手段,区块链技术解决了防伪标签不可靠和溯源信息不完整等问题,其赋能于食品供应链溯源,不仅依靠分布式存储机制保存电子证据,还将处方药溯源和电子病历相结合,实现全生命周期溯源。结论 区块链技术有效解决消费者对食品安全的信任问题,实现可靠且高效的电子存证,为未来医药一体化打下坚实基础。  相似文献   

6.
In the past decade, blockchain has evolved as a promising solution to develop secure distributed ledgers and has gained massive attention. However, current blockchain systems face the problems of limited throughput, poor scalability, and high latency. Due to the failure of consensus algorithms in managing nodes’identities, blockchain technology is considered inappropriate for many applications, e.g., in IoT environments, because of poor scalability. This paper proposes a blockchain consensus mechanism called the Advanced DAG-based Ranking (ADR) protocol to improve blockchain scalability and throughput. The ADR protocol uses the directed acyclic graph ledger, where nodes are placed according to their ranking positions in the graph. It allows honest nodes to use the Direct Acyclic Graph (DAG) topology to write blocks and verify transactions instead of a chain of blocks. By using a three-step strategy, this protocol ensures that the system is secured against doublespending attacks and allows for higher throughput and scalability. The first step involves the safe entry of nodes into the system by verifying their private and public keys. The next step involves developing an advanced DAG ledger so nodes can start block production and verify transactions. In the third step, a ranking algorithm is developed to separate the nodes created by attackers. After eliminating attacker nodes, the nodes are ranked according to their performance in the system, and true nodes are arranged in blocks in topological order. As a result, the ADR protocol is suitable for applications in the Internet of Things (IoT). We evaluated ADR on EC2 clusters with more than 100 nodes and achieved better transaction throughput and liveness of the network while adding malicious nodes. Based on the simulation results, this research determined that the transaction’s performance was significantly improved over blockchains like Internet of Things Applications (IOTA) and ByteBall.  相似文献   

7.
随着空调领域大数据和智能化的飞速发展,良好的数据管理模式变得十分重要.本文首次提出一种将区块链作为底层技术的空调产品电子病历共享方案,旨在构建一个去中心化和第三方信任的空调病历信息共享平台.通过运用哈希计算、非对称加密和全网共识等技术,达到对空调故障病历数据的全网可信,突破个人、企业之间的信任壁垒.研究表明:基于区块链...  相似文献   

8.
Globalisation of supply chains makes their management and control more difficult. Blockchain technology, as a distributed digital ledger technology which ensures transparency, traceability, and security, is showing promise for easing some global supply chain management problems. In this paper, blockchain technology and smart contracts are critically examined with potential application to supply chain management. Local and global government, community, and consumer pressures to meet sustainability goals prompt us to further investigate how blockchain can address and aid supply chain sustainability. Part of this critical examination is how blockchains, a potentially disruptive technology that is early in its evolution, can overcome many potential barriers. Four blockchain technology adoption barriers categories are introduced; inter-organisational, intra-organisational, technical, and external barriers. True blockchain-led transformation of business and supply chain is still in progress and in its early stages; we propose future research propositions and directions that can provide insights into overcoming barriers and adoption of blockchain technology for supply chain management.  相似文献   

9.
Shuttle-based storage and retrieval systems (SBS/RSs), which are designed to increase throughput capacity and flexibility, are a type of automated storage and retrieval system used for lightweight loads. SBS/RSs can increase throughput capacity by using multiple shuttles and elevators as storage and retrieval machines (SRMs). They can also facilitate improvements in flexibility since they are able to adjust the number of SRMs according to transaction demands. Thus, determining the number of shuttles is an important issue in tier-to-tier SBS/RSs. In this paper, a decision model to determine the number of shuttles is proposed. The model is based on the travel time model, and it considers parameters such as the physical configuration, velocity profile and the probability that the shuttle operates a dual command. Finally, the throughput capacity from the travel time model is compared with that from a simulation-based approach in order to verify the effects of the model. In addition, a critical discussion regarding the characteristics of the tier-to-tier system is provided.  相似文献   

10.
During the COVID-19 pandemic, the current operating environment of pharmaceutical supply chain (PSC) has rapidly changed and faced increasing risks of disruption. The Internet of Things (IoT) and blockchain not only help enhance the efficiency of PSC operations in the information technology domain but also address complex related issues and improve the visibility, flexibility, and transparency of these operations. Although IoT and blockchain have been widely examined in the areas of supply chain and logistics management, further work on PSC is expected by the public to enhance its resilience. To respond to this call, this paper combines a literature review with semi-structured interviews to investigate the characteristics of PSC, the key aspects affecting PSC, and the challenges faced by PSC in the post-pandemic era. An IoT–blockchain-integrated hospital-side oriented PSC management model is also developed. This paper highlights how IoT and blockchain technology can enhance supply chain resilience and provides a reference on how PSC members can cope with the associated risks.  相似文献   

11.
Cold-chain logistics system (CCLS) plays the role of collecting and managing the logistics data of frozen food. However, there always exist problems of information loss, data tampering, and privacy leakage in traditional centralized systems, which influence frozen food security and people’s health. The centralized management form impedes the development of the cold-chain logistics industry and weakens logistics data availability. This paper first introduces a distributed CCLS based on blockchain technology to solve the centralized management problem. This system aggregates the production base, storage, transport, detection, processing, and consumer to form a cold-chain logistics union. The blockchain ledger guarantees that the logistics data cannot be tampered with and establishes a traceability mechanism for food safety incidents. Meanwhile, to improve the value of logistics data, a Stackelberg game-based resource allocation model has been proposed between the logistics data resource provider and the consumer. The competition between resource price and volume balances the resource supplement and consumption. This model can help to achieve an optimal resource price when the Stackelberg game obtains Nash equilibrium. The two participants also can maximize their revenues with the optimal resource price and volume by utilizing the backward induction method. Then, the performance evaluations of transaction throughput and latency show that the proposed distributed CCLS is more secure and stable. The simulations about the variation trend of data price and amount, optimal benefits, and total benefits comparison of different forms show that the resource allocation model is more efficient and practical. Moreover, the blockchain-based CCLS and Stackelberg game-based resource allocation model also can promote the value of logistic data and improve social benefits.  相似文献   

12.
Blockchain technology is considered one of the promising technologies of the information technology era. The core features of blockchain, such as decentralization, transparency, high security, and tamper-proof nature, bring great convenience for large-scale social cooperation and data sharing. Blockchain has a broad application prospect in the field of intelligent manufacturing. The key issues of this field, such as distributed collaborative production, industrial big data sharing and security, transparent logistics, and supply chain, are naturally consistent with the core characteristics of the blockchain technology. This study aims to analyze the application of blockchain in the field of intelligent manufacturing. First, we introduce the basic connotation and applications of blockchain. Then, we propose the theoretical basis for the application of blockchain in the field of intelligent manufacturing. Finally, we point out the realistic plights and provide some suggestions to promote the application of blockchain in the field of intelligent manufacturing.  相似文献   

13.

The blockchain is a technology which accumulates and compiles data into a chain of multiple blocks. Many blockchain researchers are adopting it in multiple areas. However, there are still lacks bibliometric reports exhibiting the exploration of an in-depth research pattern in blockchain. This paper aims to address that gap by analyzing the widespread of blockchain research activities conducted thus far. This study analyzed the Scopus database by using bibliometric analysis in a pool of more than 1000 articles that were published between 2013 and 2018. In particular, this paper discusses various aspects of blockchain research conducted by researchers globally. This study also focuses on the utilization of blockchain and its consensus algorithms. This bibliometric analysis discovered the following: (1) Blockchain able to solve security issues in internet of things (IoT) and would be an increasing trend in the future; (2) Researchers begin to adopt blockchain in healthcare area; (3) The most active country in blockchain publication is United States, followed by China and Germany; (4) Switzerland and Singapore are two small size countries that published few publications, however receives many citations. (5) Research collaborations between countries increased the research publications except for Canada, India, and Brazil. (6) Keyword analysis revealed that researchers are adopting blockchain to solve problems in multiple categories of the data research area (data privacy, digital storage, the security of data, big data, and distributed database). This study also highlighted the utilization and consensus of the algorithm in blockchain research.

  相似文献   

14.
Building a new decentralized domain name system based on blockchain technology is helping to solve problems, such as load imbalance and over-dependence on the trust of the central node. However, in the existing blockchain storage system, the storage overhead is very high due to its full-replication data storage mechanism. The total storage consumption for each block is up to O(n) with n nodes. Erasure code applied to blockchains can significantly reduce the storage overhead, but also greatly lower the read performance. In this study, we propose a novel coding scheme for blockchain storage, Combination Locality based Erasure Code for Permissioned blockchain storage (CLEC). CLEC uses erasure code, parity locality, and topology locality in blockchain storage, greatly reducing reading latency and repair time. In CLEC, the storage consumption per block can be reduced to O(1), and the repair penalty can also be lowered to O(1). Experiments in an open-source permissioned blockchain Tendermint show that CLEC has a maximum repair speed of 6 times and a read speed of nearly 1.7 times with storage overhead of only 1.17 times compared to the current work, a great improvement in reading performance and repair performance with slightly increased storage overhead via implementation.  相似文献   

15.
针对传统的中心化模式下外包装设计知识产权登记存在的数据易篡改、易泄露等安全问题和侵权问题,提出一种基于Hyperledger Fabric的商品外包装设计产权保护模式。以Hyperledger Fabric区块链为技术支撑,搭建去中心化、可溯源、内容不可篡改的联盟链网络,并融合星际文件系统(IPFS),提升区块链网络存储效能。同时运用所设计的多特征分层阈值检测的相似度鉴别算法模型,对商品外包装设计图像进行相似度检测。在保证设计作品原创性的前提下,调用智能合约对其进行上链确权,达到知识产权保护的目的。在包装企业、高校、研究机构等多方参与下应用此保护模式构建联盟链,对包装设计知识产权进行高效保护,这能促进包装设计产业健康发展。  相似文献   

16.
The quality traceability of precast components has largely affected the widespread adoption of prefabricated buildings. Blockchain technology provides an effective solution to change the centralized storage mode of traditional traceability system and its related disadvantages. In this paper, we propose a framework of quality traceability system for precast components based on blockchain technology. The system framework adopts a hybrid blockchain architecture and dual storage mode, defines three types of smart contracts, and creates an interactive and efficient source tracing query method, which could effectively achieve the goals of decentralization, openness, and non-tamperability, as well as efficient traceability.  相似文献   

17.
New innovations in warehouse automation systems such as autonomous vehicle-based storage and retrieval (AVS/R) system offer greater flexibility and responsiveness in processing unit-load storage and retrieval transactions in high-density storage areas. To optimise system performance, new technologies should be implemented with optimal setting of design parameters. This research is a first attempt to model a ‘zone-captive’ AVS/R system and understand the effect of number and boundary of vertical zones on system performance measures. Further, we also analyse the effect of aisle orientation within a tier on cycle times. A detailed simulation model of a multi-tier zone-captive system is built to capture the dynamics of the system i.e. interaction among the vehicles, lift and incoming transaction requests, and estimate the performance measures of interest. The numerical experiments show that the transaction cycle times can be reduced by 1–12% with optimal partitioning of vertical zones and further reduced by 0.2–15.0% by a better aisle orientation.  相似文献   

18.
上下冲击式速冻机流场和换热特性研究现状   总被引:1,自引:0,他引:1  
目的 为了提高食品冻结的品质,需要对冲击式速冻机的结构尺寸和内部流场进行优化,改善冲击式速冻机的冻结效率.方法 综述影响该类速冻机换热特性的4个因素,即喷嘴的形状和尺寸,射流阵列的排布,喷嘴到输送带距离和喷嘴间距的改变,速冻机进出口压差等.结果 通过回顾计算流体力学技术和实验研究在这4个方面优化速冻机换热特性的案例,总结了上下冲击式速冻机流场变化的规律.结论 该研究为新型速冻机的优化设计提供了理论支撑.  相似文献   

19.
There has been tremendous interest in blockchain technology (BT) (also known as distributed ledger technology) around the globe and across sectors. Following significant success in the financial sector, other sectors, such as humanitarian sector, have started deploying BT at various levels. Although the use of BT in the humanitarian sector is in its infancy, donors and government agencies are increasingly calling for building BT-enabled swift-trust (ST) and more collaborative relationships among various humanitarian actors in order to improve the transparency and traceability of disaster relief materials, information exchanges and flow of funds in disaster relief supply chains. Our study, which is informed by organisational information processing theory and relational view, proposes a theoretical model to understand how BT can influence operational supply chain transparency (OSTC) and ST among actors engaged in disaster relief operations. Our model also shows how BT-enabled ST can further improve collaboration (CO) among actors engaged in disaster relief operations and enhance supply chain resilience (SCR). We formulated and tested six research hypotheses, using data gathered from international non-governmental organisations with the help of the Coordinator for Humanitarian Affairs (OCHA) database. We received 256 usable responses using a pre-tested survey-based instrument designed for key informants. Our results confirm that our six hypotheses were supported. Our study offers significant and valid contributions to the literature on ST, CO and SCR and BT/distributed ledger technology. We have also noted the limitations of our study and have offered future research directions.  相似文献   

20.
There are numerous internet-connected devices attached to the industrial process through recent communication technologies, which enable machine-to-machine communication and the sharing of sensitive data through a new technology called the industrial internet of things (IIoTs). Most of the suggested security mechanisms are vulnerable to several cybersecurity threats due to their reliance on cloud-based services, external trusted authorities, and centralized architectures; they have high computation and communication costs, low performance, and are exposed to a single authority of failure and bottleneck. Blockchain technology (BC) is widely adopted in the industrial sector for its valuable features in terms of decentralization, security, and scalability. In our work, we propose a decentralized, scalable, lightweight, trusted and secure private network based on blockchain technology/smart contracts for the overhead circuit breaker of the electrical power grid of the Al-Kufa/Iraq power plant as an industrial application. The proposed scheme offers a double layer of data encryption, device authentication, scalability, high performance, low power consumption, and improves the industry’s operations; provides efficient access control to the sensitive data generated by circuit breaker sensors and helps reduce power wastage. We also address data aggregation operations, which are considered challenging in electric power smart grids. We utilize a multi-chain proof of rapid authentication (McPoRA) as a consensus mechanism, which helps to enhance the computational performance and effectively improve the latency. The advanced reduced instruction set computer (RISC) machines ARM Cortex-M33 microcontroller adopted in our work, is characterized by ultra-low power consumption and high performance, as well as efficiency in terms of real-time cryptographic algorithms such as the elliptic curve digital signature algorithm (ECDSA). This improves the computational execution, increases the implementation speed of the asymmetric cryptographic algorithm and provides data integrity and device authenticity at the perceptual layer. Our experimental results show that the proposed scheme achieves excellent performance, data security, real-time data processing, low power consumption (70.880 mW), and very low memory utilization (2.03% read-only memory (RAM) and 0.9% flash memory) and execution time (0.7424 s) for the cryptographic algorithm. This enables autonomous network reconfiguration on-demand and real-time data processing.  相似文献   

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