【Author】 Blasco, N. Corredor, P. Satrustegui, N.
【影响因子】6.793
【主题类别】
区块链治理--
【Abstract】This paper analyses the herding behaviour among exchanges around the expiration of bitcoin futures traded on the Chicago Mercantile Exchange (CME). The database extends from December 2017 to October 2020, taking as a reference the main exchanges that trade bitcoin (Binance, Bitfinex, Bitstamp, Coinbase, itBit, Kraken, and Gemini) and using hourly closing prices and trading volumes in bitcoin and US dollars. Adapting the proposal of Chang, Cheng and Khorana (2000) (CCK) to test conditional herding, we obtain results that indicate that the herding effect is significant during the week before expiration. After expiration, the herding effect lasts for a few hours and disappears. Information overload originating, among other causes, from sophisticated investors' strategies may generate this mimetic behaviour. The results show the relevance of intraday data applied to specific events such as expiration since the unconditional analysis shows, in general, anti-herding behaviour throughout the period of study.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Herding; Expiration effect; Bitcoin; Futures; Exchanges; Intraday data
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 期刊
【影响因子】6.595
【主题类别】
区块链技术-区块链数据分析-
【Abstract】Current cryptocurrencies, such as Bitcoin and Ethereum, enable anonymity by using public keys to represent user accounts. On the other hand, inferring blockchain account types (i.e., miners, smart contracts or exchanges), which are also referred to as blockchain identities, is significant in many scenarios, such as risk assessment and trade regulation. Existing work on blockchain deanonymization mainly focuses on Bitcoin that supports simple transactions of cryptocurrencies. As the popularity of decentralized application (DApp) platform blockchains with Turing-complete smart contracts, represented by Ethereum, identity inference in blockchain faces new challenges because of user diversity and complexity of activities enabled by smart contracts. In this paper, we propose I(2)GL, an identify inference approach based on big graph analytics and learning to address these challenges. Specifically, I(2)GL constructs a transaction graph and aims to infer the identity of nodes using the graph learning technique based on Graph Convolutional Networks. Furthermore, a series of enhancement has been proposed by exploiting unique features of blockchain transaction graph. The experimental results on Ethereum transaction records show that I(2)GL significantly outperforms other state-of-the-art methods.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Blockchain; anonymity; identity inference; graph learning
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 期刊
【影响因子】4.481
【主题类别】
区块链治理--
【Abstract】Purpose Cryptocurrency, an important application of blockchain technology, has gradually circulated, and its use has become widespread. While cryptocurrency is growing rapidly, potential risks are simultaneously emerging. Users thus may abandon their usage behavior of cryptocurrency, hindering the future development of cryptocurrency. While prior studies focus more on the intention to use cryptocurrency in the pre-adoption phase, less studies pay attention to discontinuance usage intention in the post-adoption phase. To fill this knowledge gap, this stfudy aims to explore factors that cause discontinuance usage intention regarding cryptocurrency. Design/methodology/approach Based on the net valence framework theoretically grounded on the theory of reason action, a dilemmatic dual-factor model is proposed to figure out cryptocurrency users' discontinuance usage intention from the perceived risk and perceived benefit. This study identifies four potential risks and three potential benefits that affect perceived risk and benefit. The model with nine hypotheses were developed, and research data were collected by a survey method. A total of 343 valid responses were received, and PLS-SEM with SmartPLS was utilized to test the nine hypotheses, with seven hypotheses supported empirically. Findings Our findings demonstrate that financial, legal and operational risks are critical to increase users' perceived risk, and perceived usefulness and seamless transactions play important roles in enhancing users' perceived benefit. Moreover, while perceived risk can increase users' discontinuance usage intention to cryptocurrency, perceived benefit can mitigate such intention. Originality/value This study contributes nascent knowledge to the literature by examining factors that influence discontinuous usage intention in regard to cryptocurrencies, to firms that have issued or attempted to issue cryptocurrencies and to the potential users of cryptocurrencies by adjusting the mode of operation and investment strategies and reducing user costs, achieving a win-win situation for firms and users.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Cryptocurrency; Discontinuance usage; Post-adoption behavior; Perceived risk; Perceived benefit
【发表时间】
【收录时间】2022-03-28
【文献类型】 期刊
【DOI】 10.1108/ITP-11-2020-0778
【影响因子】3.860
【主题类别】
区块链应用-政务领域-
【Abstract】Election allows the voter of a country to select the most suitable group of candidates to run the government. Election in Pakistan is simply paper-based method but some certain political and socio-economic issues turn that simple process in complicated and disputes once. Solutions of such problems are consisting of many methods including the e-voting system. The e-voting system facilitates the voters to cast their votes by electronic means with very easy and convenient way. This also allows maintaining the security and secrecy of the voter along with election process. Electronic voting reduces the human-involvement throughout the process from start to the end. Such system is not established yet in Pakistan. Hence, every election is disputed always. In this paper we proposed the framework of an e-voting system and simulation with the use of blockchain ledger technology. The proposed framework owns the capacity to deal with ballots in Pakistan. The novelty of the framework is that the e-voting system is linked to National Database and Registration Authority (NADRA) database which assures voter's validation. The fundamental requirements were kept in consideration during the performance evaluation of the system. The results are processed and depicted specially with reference to the number of voters and voting stations, real time of vote casting, network bandwidth and controlling principles. The results support the decision makers and guide them in the foundation and customization of an e-voting system in Pakistan.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Simulation modeling; e-voting system; blockchain technology; distributed ledger
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 期刊
【DOI】 10.32604/cmc.2022.023846
【Author】 Zamani, Efpraxia D.
【影响因子】3.633
【主题类别】
区块链治理--
【Abstract】In this study, I use the Critical Realism perspective of power to explain how the Bitcoin protocol operates as a system of power. I trace the ideological underpinnings of the protocol in the Cypherpunk movement to consider how notions of power shaped the protocol. The protocol by design encompasses structures, namely Proof of Work and Trustlessness that reproduce asymmetrical constraints on the entities that comprise it. These constraining structures generate constraining mechanisms, those of cost effectiveness and deanonymisation, which further restrict participating entities' 'power to act', reinforcing others' 'power over' them. In doing so, I illustrate that the Bitcoin protocol, rather than decentralising and distributing power across a network of numerous anonymous, trustless peers, it has instead shifted it, from the traditional actors (e.g., state, regulators) to newly emergent ones.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Decentralisation; Power; Bitcoin; Critical realism
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 期刊
【Author】 Wang, Shacheng Zhu, Xixi
【影响因子】3.000
【主题类别】
区块链治理--
【Abstract】Terrorist financing is the economic basis of terrorist activities and the lifeline of terrorist organizations. In recent years, terrorist organizations have gradually come to use cryptocurrency to finance their activities based on traditional ways of raising funds. The anonymity of cryptocurrency is attractive to terrorist organizations, but its use remains at a low level. To explore the future development ability of cryptocurrency in terrorist financing, we study its internal characteristics and development status, as well as the supervisory systems of international organizations. This study hopes to enhance our understanding of the potential risks of cryptocurrency and serve as a reference for the fight against terrorist financing in the international community.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 期刊
【DOI】 10.1093/police/paab059
【Author】 Park, Young-Hoon Kim, Yejin Shim, Junho
【影响因子】2.690
【主题类别】
区块链应用-医疗领域-
【Abstract】The advances made in genome technology have resulted in significant amounts of genomic data being generated at an increasing speed. As genomic data contain various privacy-sensitive information, security schemes that protect confidentiality and control access are essential. Many security techniques have been proposed to safeguard healthcare data. However, these techniques are inadequate for genomic data management because of their large size. Additionally, privacy problems due to the sharing of gene data are yet to be addressed. In this study, we propose a secure genomic data management system using blockchain and local differential privacy (LDP). The proposed system employs two types of storage: private storage for internal staff and semi-private storage for external users. In private storage, because encrypted gene data are stored, only internal employees can access the data. Meanwhile, in semi-private storage, gene data are irreversibly modified by LDP. Through LDP, different noises are added to each section of the genomic data. Therefore, even though the third party uses or exposes the shared data, the owner's privacy is guaranteed. Furthermore, the access control for each storage is ensured by the blockchain, and the gene owner can trace the usage and sharing status using a decentralized application in a mobile device.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】gene; blockchain; local differential privacy; DApp
【发表时间】2021
【收录时间】2022-03-28
【文献类型】 期刊
【Author】 Melo, Carlos Oliveira, Felipe Dantas, Jamilson Araujo, Jean Pereira, Paulo Maciel, Ronierison Maciel, Paulo
【影响因子】2.557
【主题类别】
区块链技术-性能评估-
【Abstract】Through the blockchain-as-a-service paradigm, one can provide the infrastructure required to host blockchain-based applications regarding performance and dependability-related attributes. Many works evaluated issues and mitigated them to reach a high throughput or better downtime and availability indexes. However, to the best of our acknowledgment, studies regarding both characteristics are yet to be performed. This paper presents a performance evaluation of a private infrastructure hosting a blockchain-based application. As we monitored the system, we noticed some increase in resource consumption that may be associated with software aging issues on the hyperledger fabric platform or its basic components. Also, the impact of this resource increment on the probability of the system being operational has been evaluated. When consumption issues were considered, one of the transaction types increased the RAM consumption by almost 80% in less than 3 h, reducing the system availability to 98.17%. For scenarios without resource increment issues on the infrastructure, the availability reached 99.35%, with an annual downtime of 56.43 h.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Blockchain; Performance; Measurement; Software aging; Availability
【发表时间】
【收录时间】2022-03-28
【文献类型】 期刊
【影响因子】1.831
【主题类别】
区块链应用-物流领域-
【Abstract】Security and privacy of information transmitted among the devices involved in an Internet of Things (IoT) network represent relevant issues in IoT contexts. Guaranteeing effective control and supervising access permissions to IoT applications is a complex task, mainly due to resources' heterogeneity and scalability requirements. The design and development of highly customizable access control policies, along with an efficient mechanism for ensuring that the rules applied by the IoT platform are not tampered with or violated, will undoubtedly have a significant impact on the diffusion of IoT-based solutions. In such a direction, the article proposes the integration of a permissioned blockchain within an honest-but-curious (i.e., not trusted) IoT distributed middleware layer, which aims to guarantee the correct management of access to resources by the interested parties. The result is a robust and lightweight system, able to manage the data produced by IoT devices, support relevant security features, such as integrity and confidentiality, and resist different kinds of attacks. The use of blockchain will ensure the tamper-resistance and synchronization of the distributed system, where various stakeholders own applications and IoT platforms. The methodology and the proposed architecture are validated employing a test-bed.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】blockchain; fog computing; Internet of Things; privacy; security; sticky policy
【发表时间】
【收录时间】2022-03-28
【文献类型】 期刊
【DOI】 10.1002/cpe.6934
【Author】 Kumaran, Sunitha
【影响因子】0.925
【主题类别】
区块链治理--
【Abstract】The appealing features of cryptocurrency in the digital money sector have put them into the category of investable assets. Investment professionals have begun to consider their investability and diversification benefits. It is vital for investors to understand the return-risk behaviour among investable assets to reap the benefits of diversification. This paper considers a proxy of cryptos, specifically Bitcoin, Litecoin, Ethereum, Ripple & Neo, and the Middle East stock market indices, to examine the dynamic relationship among them using the vector error correction model. This study found evidence to suggest that cryptos exhibit a co-integrated relationship while there is no evidence of significant cointegrated movements occurring between the cryptos and the market indices. The latter finding implies that cryptos are decoupled from the market indices and can serve as a diversification option for investors. The mean-variance approach confirms that cryptocurrencies fit into an optimal portfolio and involve an enhanced return-risk reward for investors.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】portfolio diversification; cryptocurrency; mean-variance portfolio; cointegration; VECM
【发表时间】
【收录时间】2022-03-28
【文献类型】 期刊
【Author】 Shi, Cheng Yoneyama, Kazuki
【影响因子】0.423
【主题类别】
区块链技术-智能合约-
【Abstract】Smart contracts are protocols that can automatically execute a transaction including an electronic contract when a condition is satisfied without a trusted third party. In a representative use-case, a smart contract is executed when multiple parties fairly trade on a blockchain asset. On blockchain systems, a smart contract can be regarded as a system participant, responding to the information received, receiving and storing values, and sending information and values outwards. Also, a smart contract can temporarily keep assets, and always perform operations in accordance with prior rules. Many cryptocurrencies have implemented smart contracts. At POST2018, Atzei et al. give formulations of seven fair exchange protocols using smart contract on Bitcoin: oracle, escrow, intermediated payment, timed commitment, micropayment channels, fair lotteries, and contingent payment. However, they only give an informal discussion on security. In this paper, we verify the fairness of their seven protocols by using the formal verification tool ProVerif. As a result, we show that five protocols (the oracle, intermediated payment, timed commitment, micropayment channels and fair lotteries protocols) satisfy fairness, which were not proved formally. Also, we re-find known attacks to break fairness of two protocols (the escrow and contingent payment protocols). For the escrow protocol, we formalize the two-party scheme and the three-party scheme with an arbitrator, and show that the two-party scheme does not satisfy fairness as Atzei et al. showed. For the contingent payment protocol, we formalize the protocol with the non-interactive zero-knowledge proof (NIZK), and re-find the attack shown by Campanelli et al. at CCS 2017. Also, we show that a countermeasure with subversion NIZK against the attack works properly while it is not formally proved.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】formal methods; smart contracts; fairness; ProVerif
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 期刊
【影响因子】0.000
【主题类别】
区块链应用-医疗领域-
【Abstract】Over the past two decades, the fast pace of digitization in the healthcare ecosystem led to a phenomenal rise in the creation, storage and sharing of Electronic Health Records (EHRs) across the globe. However, the mechanism of authentication used for proving the identity of entities in EHRs is based on the identifiers issued by centralized identity providers (IDPs). It may lead to a single point of failure, loss of privacy and lack of interoperability. A new wave of decentralized identifiers (DIDs) and verifiable credentials(VCs) data modelled by blockchain has made it possible to achieve entity authentication in a decentralized manner. In this study, a blockchain-based framework with decentralized identifiers for patient authentication and consent management for EHR access using verifiable credentials is proposed. It describes the process of DID generation and authentication credential setup along with workflows for issuing and verifying credentials in the EHR ecosystem. The framework is implemented using Hyperledger Indy blockchain and Aries library. The study evaluates the performance of proposed workflows in terms of scalability, efficiency, resource utilization and conducts security analysis. Specifically, the outcome of this study can be used to realize the decentralized identity management and authentication in EHR systems.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Electronic Health Records; Blockchain; Decentralizied Identifiers; Entity Authentication; Verifiable Credentials; Hyperledger Aries; Hyperledger Indy
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 期刊
【影响因子】0.000
【主题类别】
区块链应用-金融领域-
【Abstract】In the financial services industry, many people assume blockchain to have significant impacts. From research and practice, we observe two main paradigms of how organizations interact with blockchain. First, organizations use blockchain to optimize existing processes (blockchain-based business process optimization (BPO)). Second, organizations use blockchain to disrupt existing processes, foster disintermediation, and enable disruptive business models (blockchain-based business process disruption (BPD)). However, we lack scientific research that evaluates its de facto potential. We bridge this gap by following a design science research approach to design blockchain-based business process re-engineering (BPRE) for a letter of credit that combines the advantages of BPO and BPD. We conduct three design cycles and develop three artefacts: a BPO, a BPD, and a BPRE approach. Our BPRE approach combines the advantages of partial disintermediation (i.e., increased efficiency and transparency) with the advantages of intermediaries (i.e., process flexibility, liquidity provision, and dispute mediation).
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Blockchain; Business Process Management; Disintermediation; Letter of Credit; International Trade Finance; Smart Contract
【发表时间】2021
【收录时间】2022-03-28
【文献类型】 期刊
【DOI】 10.17705/1CAIS.04932
【影响因子】0.000
【主题类别】
区块链治理--
【Abstract】Purpose Given the growing importance of cryptocurrencies and the technique called "SegWit" that allows to compile more transactions in a mined block, the electricity consumed per block might potentially decrease. The purpose of this study is to consider that the difficulty to mine a block might be a better indicator of the Bitcoin\Ether's electricity consumption. Design/methodology/approach This study applies the vector error correction model to investigate data related to primary energy consumption and electricity production, supply and consumption for Bitcoin and Ether hashrates from 2016M1 to 2021M5. Findings The hashrate (difficulty of solving the cryptographic problem related to the validation of a transaction) is found to have a positive cointegration with energy and electricity consumption. Despite the launch of the Segregation Witness (SegWit) mechanism allowing blocks to handle a higher number of transactions per block, this Bitcoin and Ether growing need in electricity has significantly been increasing since October 2019. Originality/value The major contribution of this study is to investigate a more relevant indicator, namely, hashrate (computational difficulty to solve cryptographic enigma associated with cryptocurrencies-related transaction). The approach of this study can be justified by the fact that there exists a technical solution consisting in increasing the number of transactions per blocks so that less electricity might be required to validate a transaction.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】Electricity consumption; Bitcoin; Ether; Hashrate
【发表时间】
【收录时间】2022-03-28
【文献类型】 期刊
【DOI】 10.1108/SEF-08-2021-0342
【Author】 Zhu, Yu-Peng Park, Han-Woo
【影响因子】3.889
【主题类别】
综述--
【Abstract】Blockchain, as a new innovative technology, has become a popular topic in many fields in recent years. In this study, triangulation was used to investigate the development of knowledge structures. First, scientometric network analysis was employed to identify the cooperation of knowledge networks. It was found that the structure of blockchain knowledge networks in China is relatively more complex and diverse than in South Korea. Since increased teamwork in blockchain is conducive to the creation of high-quality knowledge products, the Chinese government appears to strongly promote diversified cooperation on blockchain technology through centralized policies. Second, machine-learning topic modeling was used to analyze the content exchanged via a collaborative network. As a result, it was found that both countries lacked the societal and commercial aspects of blockchain technology. Finally, we developed a prediction technique based on the Ernie model to automatically categorize the nature of blockchain research.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】triangulation; scientometric; network analysis; blockchain
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 综述
【DOI】 10.3390/su14042326
【Author】 Shetty, Ankitha Shetty, Adithya D. Pai, Rashmi Yogesh Rao, Rohini R. Bhandary, Rakshith Shetty, Jyothi Nayak, Santosh Dinesh, Tantri Keerthi Dsouza, Komal Jenifer
【影响因子】2.032
【主题类别】
综述--
【Abstract】The Insurance industry participates in various processes that are characterized by data exchange, which is modified or updated by many parties. Hence, the insurance industry can benefit from the adoption of blockchain technology. However, there is a lack of understanding of the technology, the legal implications and the issues in implementing the technology. This paper aims at finding potential opportunities for the insurance sector on the implementation of blockchain technology. It also discusses issues and concerns for insurance companies wanting to adopt block chain technologies. A search was carried out for relevant electronic bibliographic databases (searched by means of keywords), articles published in scientific journals, websites of consultancy firms and blockchain developers, and reference lists of relevant review articles. Articles were screened and eligibility was based on participants, procedures, interventions comparisons, outcomes (PICO) model and criteria for PRISMA (Preferred Reporting Items for Systematic Reviews). A total of 23 papers were finalized after scrutiny for this study whereby the results disclose that blockchain, as a single source of reality, has the potential to improve productivity and mitigate the complexity of the insurance processes. Examples of real-world applications and insurance use cases are presented to demonstrate the strengths & capabilities of the technology. This study also considers the present-day issues, risks and concerns in the implementation of the blockchain technology. Finally, the challenges and obstacles in the application of Blockchain technology in the Insurance Sector is highlighted and presented.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】distributed ledger technology; blockchain; insurance; risk management; smart contracts; cryptography; hyperledger; Ethereum; Bitcoins
【发表时间】2022
【收录时间】2022-03-28
【文献类型】 综述
【影响因子】0.000
【主题类别】
综述--
【Abstract】The 21st century has introduced the 4th Industrial Revolution, which describes an industrial paradigm shift that alters social, economic, and political environments simultaneously. Innovative technologies such as blockchain, artificial intelligence, and advanced mobile networks power this digital revolution. These technologies provide a unique component that, when integrated, will establish a foundation to drive future innovation. In this paper, we summarize a 2019 Association for Information Systems Americas Conference on Information Systems (AMCIS) panel session where researchers who specialize in these technologies discussed new innovations and their integration. This topic has significant implications to business and academia both as these technologies will disrupt the social, economic, and political landscapes.
你可以尝试使用大模型来生成摘要 立即生成
【Keywords】4th Industrial Revolution; Fifth Generation (5G) New Radio (NR); Blockchain; Artificial Intelligence; Machine Learning; Enabling Technology; Technological Integration
【发表时间】2021
【收录时间】2022-03-28
【文献类型】 综述
【DOI】 10.17705/1CAIS.04910