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元宇宙是虚拟数字世界与真实物理世界无缝融合的新生态,近来引发了各界的广泛关注。区块链、人工智能、虚拟现实/增强现实及传感技术、移动通信及泛在计算等各种新型互联网技术愈发成熟,使元宇宙的进一步发展成为可能。关于元宇宙的研究主要涉及产业项目、基础设施、关键技术、隐私安全等方面,这些研究虽然涉及区块链技术,但未具体指出区块链应用于元宇宙的优势及具体应用方式。区块链技术不仅可以为元宇宙提供开放自由的去中心化环境,而且可以为其提供公平合理的数字资产分配机制。主要从区块链赋能元宇宙中数字身份和数字资产管理的角度出发,分析了元宇宙的发展历程和特征,讨论了元宇宙发展所需核心技术及面临的挑战。同时研究了区块链的关键技术,并从区块链的本质特征及与其他技术融合优势两个方面对区块链应用于元宇宙做可行性分析。进一步提出元宇宙生态体系架构,重点详细分析了基于区块链的自我主权身份管理模型、区块链-非同质化通证（NFT,non-fungible token）工作流程及其在元宇宙中的应用。结合区块链和元宇宙的最新研究进展,从基础设施、通信和计算资源管理机制、监管与隐私保护以及区块链可扩展和互操作性4个方面指出区块链应用... 相似文献
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Yuan Fang; 《Expert Systems》2024,41(5):e12989
In order to improve the reliability of Tibetan Thangka sales channels, this paper combines blockchain technology to construct an intelligent model that can be used for Tibetan Thangka sales. This paper uses cryptographic encryption technology to encrypt the uploaded data to prevent Thangka producers or logistics turnover parties from tampering with Thangka-related information, and uses the timestamp in blockchain technology to realize the traceability of Thangka-related information. In addition, this paper uses the timestamp technology in the blockchain system to generate a traceable, query and supervised blockchain, which runs through the whole process of thangka from planting to selling. Finally, a sales model of Tibet Thangka based on blockchain technology is designed, and system performance analysis is carried out through simulation experiments. The experimental research results verify that the designed sales model has a certain effect. 相似文献
4.
Otto Julio Ahlert Pinno Andr Ricardo Abed Grgio Luis C.E. De Bona 《Concurrency and Computation》2020,32(12)
The IoT is changing the way we interact with the world. Very soon, almost all of our daily tasks will be made through self intelligent systems embedded in devices scattered all around us. Their mission is to turn our cities, transportation systems, buildings, homes, and bodies in smart environments. These environments will bring us more comfort, improve our performance, increase our profits, and take away time‐consuming tasks. However, besides its great benefits, the IoT is also a big source of concerns, mainly because a good part of its devices will handle private and confidential information. Recently, cases of successful IoT invasions only worsen this scenario and show us that the today's adopted access control systems need to be replaced by more efficiently and secure ones. To overcome these access control problems, in this work, we present the ControlChain. The ControlChain is an access control authorization architecture that is heavily based on Blockchain technology. We also demonstrate the viability of the ControlChain through the E‐ControlChain, a proof‐of‐concept developed to run over the Ethereum network. Our proposals follows the IoT tendency requirements and are user‐transparent, user‐friendly, fully decentralized, scalable, fault tolerant, and compatible with a wide range of today's access control models already used in the IoT. Finally, we also make a cost and a performance analysis of E‐ControlChain, using a Raspberry Pi as an IoT device. 相似文献
5.
Lasse Herskind Alberto Giaretta Michele De Donno Nicola Dragoni 《Concurrency and Computation》2020,32(12)
Disbursement registration has always been a cumbersome, opaque, and inefficient process, up to the point that most businesses perform cash‐flow evaluations only on a quarterly basis. We believe that automatic cash‐flow evaluations can actively mitigate these issues. In this paper, we present BitFlow, a blockchain‐based architecture that provides complete cash‐flow transparency and diminishes the probability of undetected frauds through the BitKrone, a non‐volatile cryptocurrency that maps to the Danish Krone (DKK ). We show that confidentiality can be effectively achieved on a permissionless blockchain using Zero‐Knowledge proofs, ensuring verifiable transfers and automatic evaluations. Furthermore, we discuss several experiments to evaluate our proposal, in particular, the impact that confidential transactions have on the whole system, in terms of responsiveness and from an economical expenditure perspective. 相似文献
6.
Ya‐Nan Li Xiaotao Feng Jan Xie Hanwen Feng Zhenyu Guan Qianhong Wu 《Concurrency and Computation》2020,32(7)
As the value of data has received considerable attention, data trading shows broad market prospects. The existing data trading methods, including private trades and centralized trades, have high risks regarding transaction security and data protection. To solve this problem, we propose a decentralized trading solution for open fair data trading by deploying the smart contract on the blockchain network. The data for sale are encrypted and stored on the distributed storage platform but not directly on the blockchain network. Because the trading content is the decryption key of the data, the proposed new method can alleviate the storage pressure of the blockchain by reducing the transaction cost. We conduct a security analysis which shows that our scheme achieves secure, practical, open, and fair trading. We implement our trading contract with solidity and test it on the Ethereum's test network, and extensive experiments demonstrate desirable feasibility of our proposal. 相似文献
7.
Blockchain sharding is a promising approach to solving the dilemma between decentralization and high performance (transaction throughput) for blockchain. The main challenge of blockchain sharding systems is how to reach a decision on a statement among a subgroup (shard) of people while ensuring the whole population recognizes this statement. Namely, the challenge is to prevent an adversary who does not have the majority of nodes globally but have the majority of nodes inside a shard. Most blockchain sharding approaches can only reach a correct consensus inside a shard with at most n/3 evil nodes in a n node system. There is a blockchain sharding approach which can prevent an incorrect decision to be reached when the adversary does not have n/2 nodes globally. However, the system can be stopped from reaching consensus (become deadlocked) if the adversary controls a smaller number of nodes. In this article, we present an improved Blockchain sharding approach that can withstand n/2 adversarial nodes and recover from deadlocks. The recovery is made by dynamically adjusting the number of shards and the shard size. A performance analysis suggests our approach has a high performance (transaction throughput) while requiring little bandwidth for synchronization. 相似文献
8.
Blockchain possesses the potential of transforming global supply chain management. Gartner predicts that blockchain could be able to track $2?T of goods and services in their movement across the globe by 2023, and blockchain will be a more than $3 trillion business by 2030. Nowadays, a growing number of blockchain initiatives are disrupting traditional business models in each sector. In this paper, we provide a timely and holistic overview of the state-of-the-art, challenges, gaps and opportunities in global supply chain and trade operations for both the private sector and governmental agencies, by synthesising a wide range of resources from business leaders, global international organisations, leading supply chain consulting firms, research articles, trade magazines and conferences. We then identify collaborative schema and future research directions for industry, government, and academia to jointly work together in ensuring that the full potential of blockchain is unleashed amidst the socioeconomic, geopolitical and technological disruptions that global supply chains and trade are facing. 相似文献
9.
With the emergence of distributed ledger technology (DLT), numerous practitioners and researchers have proclaimed its beneficial impact on supply chain transactions in the future. However, the vast majority of DLT initiatives are discontinued after a short period. With the full potential of DLT laying far down the road, especially managers in supply chain management (SCM) seek for short-term cost-saving effects of DLT in order to achieve long-term benefits of DLT in the future. However, the extant research has bypassed grounding long-term as well as short-term effects of DLT on supply chain transaction with empirical data. We address this shortcoming, following an abductive research approach and combining empirical data from a multiple case study design with the corresponding literature. Our study reveals that the effects of DLT on supply chain transactions are two-sided. We found six effects of DLT solutions that have a cost-reducing or cost avoidance impact on supply chain transactions. In addition, we found two effects that change the power distribution between buyers and suppliers in transactions and a single effect that reduces the dependency of supply chain transactions on third parties. While cost-reducing and avoidance as well as dependency-reducing effects are positive effects, the change in power distribution might come with disadvantages. With these findings, the paper provides the first empirical evidence of the impact of DLT on supply chain transactions, which will enable managers to improve their assessment of DLT usage in supply chains. 相似文献
10.
Bin Cao Hao Xu Lei Zhang Muhammad Imran Oluwakayode Onireti Paulo Valente Klaine 《Digital Communications & Networks》2020,6(3):261-269
The sixth-generation (6G) network must provide better performance than previous generations to meet the requirements of emerging services and applications, such as multi-gigabit transmission rate, higher reliability, and sub-1 ms latency and ubiquitous connection for the Internet of Everything (IoE). However, with the scarcity of spectrum resources, efficient resource management and sharing are crucial to achieving all these ambitious requirements. One possible technology to achieve all this is the blockchain. Because of its inherent properties, the blockchain has recently gained an important position, which is of great significance to the 6G network and other networks. In particular, the integration of the blockchain in 6G will enable the network to monitor and manage resource utilization and sharing efficiently. Hence, in this paper, we discuss the potentials of the blockchain for resource management and sharing in 6G using multiple application scenarios, namely, Internet of things, device-to-device communications, network slicing, and inter-domain blockchain ecosystems. 相似文献