【Author】 Foroutan, Parisa Lahmiri, Salim

【Source】CHAOS SOLITONS & FRACTALS

【影响因子】9.922

【主题类别】

区块链治理-市场治理-数字货币

【Abstract】Understanding the dynamics of cryptocurrency markets during financial crises such as the recent one caused by the COVID-19 pandemic is crucial for policy makers and investors. In this study, the effect of COVID-19 pandemic on the return-volatility and return-volume relationships for the ten most traded cryptocurrencies, namely Tether, Bitcoin, Ethereum, Ripple, Litecoin, Bitcoin Cash, EOS, Chainlink, Cardano, and Monero is examined. Fur-ther, the behavior of cryptocurrencies during COVID-19 pandemic is compared with less volatile markets such as Gold, WTI, and BRENT crude oil markets. To study the effect of volatility on cryptocurrency return, an EGARCH-M model is employed while for the return-volume relationships the VAR model and Granger causality tests are uti-lized. Results show that the return-volatility relationships for Tether, Ethereum, Ripple, Bitcoin Cash, EOS, and Monero are significant during COVID-19 pandemic, while the same relationship is not significant prior to the pandemic for any of the studied cryptocurrencies. Our findings of the return-volume relationship support the availability of causal relations from return to trading volume changes for Chainlink and Monero in the pre-COVID-19 period and for Ethereum, Ripple, Litecoin, EOS, and Cardano during the COVID-19 period. However, considering the absolute values of returns, we found a significant relationship from cryptocurrencies' absolute returns to trading volume changes for both the prior and during COVID-19 periods. From a managerial perspec-tive, gold can be considered a suitable asset for portfolio hedging during the pandemic period and trading volume can help traders and investors identify the effect of momentum and potential trend in cryptocurrencies on their investments.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】Cryptocurrency; Return-volume relationship; Return-volatility relationship; COVID-19 pandemic; Granger causality; EGARCH-M

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 实验仿真

【DOI】 10.1016/j.chaos.2022.112443

【Author】 Chen, Ting Li, Zihao Luo, Xiapu Wang, Xiaofeng Wang, Ting He, Zheyuan Fang, Kezhao Zhang, Yufei Zhu, Hang Li, Hongwei Cheng, Yan Zhang, Xiaosong

【Source】IEEE TRANSACTIONS ON SOFTWARE ENGINEERING CCF-A

【影响因子】9.322

【主题类别】

区块链技术-核心技术-智能合约

【Abstract】Millions of smart contracts have been deployed onto Ethereum for providing various services, whose functions can be invoked. For this purpose, the caller needs to know the function signature of a callee, which includes its function id and parameter types. Such signatures are critical to many applications focusing on smart contracts, e.g., reverse engineering, fuzzing, attack detection, and profiling. Unfortunately, it is challenging to recover the function signatures from contract bytecode, since neither debug information nor type information is present in the bytecode. To address this issue, prior approaches rely on source code, or a collection of known signatures from incomplete databases or incomplete heuristic rules, which, however, are far from adequate and cannot cope with the rapid growth of new contracts. In this paper, we propose a novel solution that leverages how functions are handled by Ethereum virtual machine (EVM) to automatically recover function signatures. In particular, we exploit how smart contracts determine the functions to be invoked to locate and extract function ids, and propose a new approach named type-aware symbolic execution (TASE) that utilizes the semantics of EVM operations on parameters to identify the number and the types of parameters. Moreover, we develop SigRec, a new tool for recovering function signatures from contract bytecode without the need of source code and function signature databases. The extensive experimental results show that SigRec outperforms all existing tools, achieving an unprecedented 98.7 percent accuracy within 0.074 seconds. We further demonstrate that the recovered function signatures are useful in attack detection, fuzzing and reverse engineering of EVM bytecode.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】Smart contracts; Databases; Reverse engineering; Semantics; Lenses; Layout; Tools; Smart contract; function signature; Ethereum; automatic recovery; type-aware symbolic execution

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 理论模型

【DOI】 10.1109/TSE.2021.3078342

【Author】 Cordes, Ashley

【Source】JOURNAL OF CULTURAL ECONOMY

【影响因子】6.613

【主题类别】

区块链治理-市场治理-数字货币

【Abstract】Since 2008, cryptocurrencies, or digital peer-to-peer currencies/assets, have amassed interest and proven unique in their ability to circumvent traditional financial institutions (disintermediation). The system can supersede the nation-state, while also garnering the attention of nation-states and marginalized groups. Indigenous individuals and Nations are among those interested in cryptocurrency, experimenting with it to express resistance to economic imposition beginning in the colonial era. Utilizing an Indigenous storytelling method, this article unveils the technological life and afterlife of an altcoin, MazaCoin, as a ghost of empire, insofar as it links the technological present of financial capital and the past (and ongoing present) of US settler colonialism. Throughout its various complicated reanimations, it expresses a relentless remembering of settler colonial injustices, performing productive haunting work within the twenty-first century cryptocurrency ecosystem. This article offers a reminder that there is much to learn about Indigenous alternative currencies in the cultural economy as the strings of racism, settler colonialism, poverty, financialization, and empire continue to tangle.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】Indigenous; settler colonialism; cryptocurrency; digital currency; MazaCoin; technological haunting

【发表时间】

【收录时间】2022-09-08

【文献类型】 观点阐述

【DOI】 10.1080/17530350.2022.2110924

【Author】 Auer, Raphael Frost, Jon Gambacorta, Leonardo Monnet, Cyril Rice, Tara Shin, Hyun Song

【Source】ANNUAL REVIEW OF ECONOMICS

【影响因子】5.970

【主题类别】

区块链治理-市场治理-数字货币

【Abstract】In just a few years, central banks have rapidly ramped up their research and development efforts on central bank digital currencies (CBDCs). A growing body of economic research informs these activities, often focusing on the "reserves for all" aspect of CBDCs for retail use. However, CBDCs should be considered in the full context of the digital economy and the centrality of data, which raises concerns around competition, payment system integrity, and privacy. This review gives a guided tour of the growing CBDC literature on the microeconomic considerations related to operation architectures, technologies, and privacy as well as the macroeconomic implications for the financial system, financial stability, and monetary policy. A set of questions, particularly on the cross-border dimensions of CBDCs, remains unresolved and calls for further work to expand the research frontier.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】money; digital currencies; central banks; central bank digital currencies; CBDC; stablecoins; cryptocurrencies; distributed ledgers; big tech; data privacy

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 观点阐述

【DOI】 10.1146/annurev-economics-051420-020324

【Author】 Mekacher, Amin Bracci, Alberto Nadini, Matthieu Martino, Mauro Alessandretti, Laura Aiello, Luca Maria Baronchelli, Andrea

【Source】SCIENTIFIC REPORTS

【影响因子】4.996

【主题类别】

区块链应用-虚拟经济-NFT

【Abstract】We quantify Non Fungible Token (NFT) rarity and investigate how it impacts market behaviour by analysing a dataset of 3.7M transactions collected between January 2018 and June 2022, involving 1.4M NFTs distributed across 410 collections. First, we consider the rarity of an NFT based on the set of human-readable attributes it possesses and show that most collections present heterogeneous rarity patterns, with few rare NFTs and a large number of more common ones. Then, we analyze market performance and show that, on average, rarer NFTs: (i) sell for higher prices, (ii) are traded less frequently, (iii) guarantee higher returns on investment, and (iv) are less risky, i.e., less prone to yield negative returns. We anticipate that these findings will be of interest to researchers as well as NFT creators, collectors, and traders.

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】2022-09-08

【文献类型】 实证数据

【DOI】 10.1038/s41598-022-17922-5

【Author】 Agur, Itai Ari, Anil Dell'Ariccia, Giovanni

【Source】JOURNAL OF MONETARY ECONOMICS

【影响因子】4.630

【主题类别】

区块链治理-市场治理-数字货币

【Abstract】The optimal design of a central bank digital currency (CBDC) is analyzed in an environment where agents sort into cash, CBDC, and bank deposits according to their preferences over anonymity and security; and where network effects make the convenience of a payment instrument depend on the number of its users. A CBDC can be designed with attributes similar to cash or deposits, and can be interest bearing: a CBDC that closely competes with deposits depresses bank credit and output, while a cash-like CBDC may lead to the disappearance of cash. Then, the optimal CBDC design trades off bank intermediation against the social value of maintaining diverse payment instruments. When network effects matter, an interest-bearing CBDC alleviates the central bank's tradeoff. (C) 2021 International Monetary Fund. Published by Elsevier B.V. All rights reserved.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】CBDC; Fintech; Digital currency; Financial intermediation; Network effects

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 观点阐述

【DOI】 10.1016/j.jmoneco.2021.05.002

【Author】 Tedeschi, Enrico Nordmo, Tor-Arne S. Johansen, Dag Johansen, Havard D.

【Source】ACM TRANSACTIONS ON INTERNET TECHNOLOGY CCF-B

【影响因子】3.989

【主题类别】

区块链治理-市场治理-数字货币

【Abstract】The transaction-rate bottleneck built into popular proof-of-work (PoW)-based cryptocurrencies, like Bitcoin and Ethereum, leads to fee markets where transactions are included according to a first-price auction for block space. Many attempts have been made to adjust and predict the fee volatility, but even well-formed transactions sometimes experience unexpected delays and evictions unless a substantial fee is offered. In this article, we propose a novel transaction inclusion model that describes the mechanisms and patterns governing miners decisions to include individual transactions in the Bitcoin system. Using this model we devise a Machine Learning (ML) approach to predict transaction inclusion. We evaluate our predictions method using historical observations of the Bitcoin network from a five month period that includes more than 30 million transactions and 120 million entries. We find that our ML model can predict fee volatility with an accuracy of up to 91%. Our findings enable Bitcoin users to improve their fee expenses and the approval time for their transactions.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】Bitcoin; blockchain; fee market; first price auction; transaction inclusion; cryptocurrencies; proof-of-work; machine learning

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 实证数据

【DOI】 10.1145/3528669

【Author】 Zichichi, Mirko Ferretti, Stefano Rodriguez-Doncel, Victor

【Source】SENSORS

【影响因子】3.847

【主题类别】

区块链治理-市场治理-市场分析

【Abstract】Big Tech companies operating in a data-driven economy offer services that rely on their users' personal data and usually store this personal information in "data silos" that prevent transparency about their use and opportunities for data sharing for public interest. In this paper, we present a solution that promotes the development of decentralized personal data marketplaces, exploiting the use of Distributed Ledger Technologies (DLTs), Decentralized File Storages (DFS) and smart contracts for storing personal data and managing access control in a decentralized way. Moreover, we focus on the issue of a lack of efficient decentralized mechanisms in DLTs and DFSs for querying a certain type of data. For this reason, we propose the use of a hypercube-structured Distributed Hash Table (DHT) on top of DLTs, organized for efficient processing of multiple keyword-based queries on the ledger data. We test our approach with the implementation of a use case regarding the creation of citizen-generated data based on direct participation and the involvement of a Decentralized Autonomous Organization (DAO). The performance evaluation demonstrates the viability of our approach for decentralized data searches, distributed authorization mechanisms and smart contract exploitation.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】distributed ledger technology; decentralized file storage; distributed hash table; data marketplace; keyword-based search; citizen-generated data

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 实证数据

【DOI】 10.3390/s22166260

【Author】 Youssef, Meriem Ben Naoua, Bouthaina Ben Abdelaziz, Fouad Chibane, Messaoud

【Source】INTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH

【影响因子】3.610

【主题类别】

区块链治理-市场治理-数字货币

【Abstract】This paper analyzes the diversification benefits of adding alternative crypto-assets in a traditional portfolio, from the perspective of an investor who seeks to achieve multiple objectives. Our analysis is based on daily and weekly return data for eight different assets including Bitcoin, Ethereum, Ripple, for the crypto-assets and NASDAQ, S&P500, Dow-Jones, Crude-Oil, and Gold, for traditional assets. We use both in-sample and out-of-sample estimation procedures to analyze these data sets. We apply the weighted sum of deviations goal programming method to solve a bi-objective optimization problem where investors optimize simultaneously portfolio risk and return. For a variety of investor characteristics, ranging from risk-seeking to risk-averse, we show that augmenting portfolios with alternative crypto-currencies improves portfolio performance and the efficiency frontier, compared to standard portfolios. This improvement is even more observable for risk-seeking investors, for both in-sample and out-of-sample estimation procedures.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】portfolio selection; crypto-assets; diversification; bi-objective optimization; goal programming

【发表时间】

【收录时间】2022-09-08

【文献类型】 实证数据

【DOI】 10.1111/itor.13203

【Author】 Ren, Yuzheng Xie, Renchao Yu, Fei Richard Huang, Tao Liu, Yunjie

【Source】IEEE TRANSACTIONS ON GREEN COMMUNICATIONS AND NETWORKING

【影响因子】3.525

【主题类别】

区块链应用-虚拟经济-NFT

【Abstract】Advanced communication and artificial intelligence (AI) technologies facilitate the development of green smart cities. Connected and automated vehicles (CAVs) are crucial components, which are aware of the environment by collecting data from sensors and modeling through AI to realize automatic decision-making. Intelligence networking enables each CAV to train appropriate models locally to learn how to drive in different environments, which can make up for the lack of experience of single-vehicle. However, model training and intelligence networking consume a lot of energy, calling on high-energy-efficient solutions. In this paper, we propose a non-fungible token (NFT)-based green intelligence networking scheme (NGIN) for CAVs in smart cities. We use NFT to tokenize and describe intelligence by metadata, enabling applications to network intelligence efficiently, thereby reducing energy consumption. We present the architecture, modules, and efficient mechanisms of distributed intelligence networking. Moreover, we formulate the core problem as a discrete Markov decision process (MDP) and adopt the quantum-inspired reinforcement learning (QRL) algorithm to solve it. Also, the convergence rate and performance are evaluated. Simulation results demonstrate the effectiveness of the proposed scheme.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】Blockchains; Training; Computational modeling; Smart cities; Metadata; Computer architecture; Smart contracts; Smart cities; green; intelligence networking; non-fungible token (NFT)

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 理论模型

【DOI】 10.1109/TGCN.2022.3148293

【Author】 Haga, Shinya Omote, Kazumasa

【Source】IEEE ACCESS

【影响因子】3.476

【主题类别】

区块链应用-实体经济-政务领域

【Abstract】In recent years, the spread of information and communication technology has led to the emergence of e-government, which is the electronic replacement of government services. E-government is said to be compatible with blockchain technology, which has led to various studies on the possibility. Notarization, one of the functions of the government, has particularly been examined for the potential adoption of blockchain technology. However, because the notary public must authenticate the document's contents during the notarization process, they have been difficult to replace with smart contracts. In this study, we focus only on fixed date notarizations and propose a fully automated notarization system by combining a national eID card with Public Key Infrastructure and smart contracts. A fixed date is a notarization that allows a notary public to guarantee that a document existed, regardless of the authenticity of the document's content. Therefore, it can be replaced by a smart contract. Specifically, our proposed system automatically authenticates the creator and the document for electronic documents signed with a national eID card and uses the transaction receipt generated when the information is stored on the blockchain as a certificate of notarization. Verification of the signed data is done inside the blockchain by smart contracts, which eliminates the need for a verification authority. We further demonstrate the effectiveness of the proposed method in a Japanese use case as proof of concept.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】Blockchains; Smart contracts; Authorization; Peer-to-peer computing; Throughput; Resistance; Public key; Autonomous systems; Information and communication technology; Electronic government; Blockchain; smart contract; Ethereum; e-government; national eID card; notarization system; authorization

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 理论模型

【DOI】 10.1109/ACCESS.2022.3199744

【Author】 Mahgoub, Shereen M. Ibrahim, I. I. Salem, Fatty M.

【Source】IEEE ACCESS

【影响因子】3.476

【主题类别】

区块链技术-核心技术-跨链与多链

【Abstract】Bitcoin is a decentralized cryptocurrency where all the transactions are saved in a ledger. Blockchains have good features to be used in different finance applications by using smart contract. Also, blockchains are attractive platform for many industrial domains, including the logistics and supply chain industries. Supply chain technology contributes to record every single asset through its flow, tracking orders, receipts, and payments. There are several relay protocols proposed in previous research; these relay protocols are used to connect different types of blockchains. In this paper, we present a Secure Organizational Transactions Framework (SOTF) based on bridge chain to connect private chain or consortium with public chain which reduces interaction with public blockchain and saves the organization details privately in private chain or consortium. The proposed framework makes it possible for smart contract services to acquire means of payment in the consortium and private chain. Moreover, the proposed framework automates the process of updating the payment non-interactively. In this paper, we validate the communication between organizations blockchain and bitcoin, and find out the development cost of the proposed framework which ensures the efficiency and feasibility of the proposed framework. The code of framework implementation is publicly available at GitHub.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】Organizations; Blockchains; Bitcoin; Supply chains; Standards organizations; Smart contracts; Protocols; Bitcoin; organizations; blockchain; consortium blockchain; supply chain; smart contract

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 理论模型

【DOI】 10.1109/ACCESS.2022.3196351

【Author】 Ibrahim, Rowaid Harby, Ahmed Alaa Nashwan, Mohamed Salem Elhakeem, Ahmed

【Source】BUILDINGS

【影响因子】3.324

【主题类别】

区块链技术-核心技术-智能合约

【Abstract】The blockchain that uses cryptocurrency is a paradigm shift in the way of data storage, retrieval, and verification due to the concept of decentralization. This paradigm is essential to ensure the security of crucial data in any project. Adding a smart contract to the blockchain would facilitate the automation of various processes. Thus, the cryptocurrency blockchain that uses the smart contract can be considered a suitable platform for an ecosystem of many industries. The construction industry needs a highly secure automated management system due to its complex contractual relationships and transactions between parties. Therefore, integrating the blockchain with the smart contract creates the most appropriate ecosystem to be developed. This study introduces an ecosystemic prototype using a programmable smart contract within a novel cryptocurrency blockchain for construction. The purpose of the prototype is to guarantee a decentralized system as an independent economic environment for the construction industry. The system guarantees the security of financial transactions and focuses on the payment clauses in the construction contract as well. The results depended on three well-known hypothetical case scenarios from the construction site and were displayed in the form of extracted access data tables. The prototype proved the efficiency of the decentralized system for the construction industry by minimizing human-factor interference in the transaction process and thus reducing time waste and cost.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】blockchain; construction; intelligent contract; smart contract; cryptocurrency; project management

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 理论模型

【DOI】 10.3390/buildings12081072

【Author】 Henshaw, Alexis

【Source】POLITICS & GENDER

【影响因子】3.165

【主题类别】

区块链治理-市场治理-市场分析

【Abstract】Decentralized finance, including cryptocurrency and other blockchain-based applications, promises participants benefits such as financial freedom, security, privacy, and wealth accumulation. More recently, it has also offered the promise of participation, lowering financial barriers, and empowerment-especially to women, the poor, and those residing in the Global South. I argue that the rise of decentralized finance as an alternative development platform is explicitly gendered and calls for feminist analysis. I discuss how cryptocurrency-based approaches to development rest on foundations that are gendered, interacting with hierarchies of race/ethnicity and class. I also explore how they are part of a lineage of neoliberalism, leveraging neoliberal beliefs about entrepreneurialism, financial inclusion, and gender roles. The discussion further introduces the concept of neolibertarianism as an extension of neoliberal logics that advocates for bypassing states entirely in favor of private actors. The current analysis compares this new model of decentralized finance to similarly problematic development trends and assesses how it has-as of yet-failed to deliver on the promises of participation, lowering financial barriers, and empowerment. This analysis concludes with a call to action for feminist and critical scholars, encouraging further work on the topic.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】gender; women; political economy; cryptocurrency; decentralized finance

【发表时间】

【收录时间】2022-09-08

【文献类型】 实证数据

【DOI】 10.1017/S1743923X22000253

【Author】 Gorski, Tomasz

【Source】SYMMETRY-BASEL

【影响因子】2.940

【主题类别】

区块链技术-核心技术-智能合约

【Abstract】A smart contract is a pivotal notion in blockchain technology. Distributed applications contain smart contracts verifying the fulfillment of the conditions, which determine the execution of transactions between the blockchain network nodes. Those software-controlled logical conditions are called verification rules. As the number of conditions increases, the complexity of smart contract testing rapidly grows. This paper aims to propose a smart contract testing pattern that significantly limits the needed number of test cases. For evaluation expression with four verification rules, the pattern usage reduces the number of test cases by 68.75% in relation to the full coverage of logical value combinations. With the increase in the number of logical conditions, not only the number of test cases but also their percentage decreases. Starting from seven verification rules in the evaluation expression, the percentage reduction of test cases exceeds 90%. As a result, the cost of preparing and maintaining test case suites may be substantially cut. It should be emphasized that test execution time can be reduced even by 3 orders of magnitude (from seconds to milliseconds). Such an approach is highly important for regression testing, especially when used in continuous software integration, delivery, and deployment approaches.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】test pattern; test suite design; smart contract; blockchain; object-oriented programming

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 理论模型

【DOI】 10.3390/sym14081686

【Author】 Smith, Roger

【Source】RESEARCH-TECHNOLOGY MANAGEMENT

【影响因子】2.855

【主题类别】

区块链应用-虚拟经济-NFT

【Abstract】

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】2022-09-08

【文献类型】 编辑社论

【DOI】 10.1080/08956308.2022.2090182

【Author】 De Collibus, Francesco Maria Piskorec, Matija Partida, Alberto Tessone, Claudio J.

【Source】ENTROPY

【影响因子】2.738

【主题类别】

区块链治理-技术治理-交易可视化

【Abstract】In this paper, we use the methods of networks science to analyse the transaction networks of tokens running on the Ethereum blockchain. We start with a deep dive on four of them: Ampleforth (AMP), Basic Attention Token (BAT), Dai (DAI) and Uniswap (UNI). We study two types of blockchain addresses, smart contracts (SC), which run code, and externally owned accounts (EOA), run by human users, or off-chain code, with the corresponding private keys. We use preferential attachment and network dismantling strategies to evaluate their importance for the network structure. Subsequently, we expand our view to all ERC-20 tokens issued on the Ethereum network. We first study multilayered networks composed of Ether (ETH) and individual tokens using a dismantling approach to assess how the deconstruction starting from one network affects the other. Finally, we analyse the Ether network and Ethereum-based token networks to find similarities between sets of high-degree nodes. For this purpose, we use both the traditional Jaccard Index and a new metric that we introduce, the Ordered Jaccard Index (OJI), which considers the order of the elements in the two sets that are compared. Our findings suggest that smart contracts and exchange-related addresses play a structural role in transaction networks both in DeFi and Ethereum. The presence in the network of nodes associated to addresses of smart contracts and exchanges is positively correlated with the success of the token network measured in terms of network size and market capitalisation. These nodes play a fundamental role in the centralisation of the supposedly decentralised finance (DeFi) ecosystem: without them, their networks would quickly collapse.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】blockchain; Ethereum; decentralised finance; network science; preferential attachment; network dismantling

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 实验仿真

【DOI】 10.3390/e24081048

【Author】 Han, Jiujiang Li, Ziyuan Liu, Jian Wang, Huimei Xian, Ming Zhang, Yuxiang Chen, Yu

【Source】ELECTRONICS

【影响因子】2.690

【主题类别】

区块链技术-核心技术-加密算法

【Abstract】Searchable encryption enables users to enjoy search services while protecting the security and privacy of their outsourced data. Blockchain-enabled searchable encryption delivers the computing processes that are executed on the server to the decentralized and transparent blockchain system, which eliminates the potential threat of malicious servers invading data. Recently, although some of the blockchain-enabled searchable encryption schemes realized that users can search freely and verify search results, unfortunately, these schemes were inefficient and costly. Motivated by this, we proposed an improved scheme that supports fine-grained access control and flexible searchable encryption. In our framework, the data owner uploads ciphertext documents and symmetric keys to cloud database and optional KMS, respectively, and manipulates the access control process and searchable encryption process through smart contracts. Finally, the experimental comparison conducted on a private Ethereum network proved the superiority of our scheme.

你可以尝试使用大模型来生成摘要 立即生成

【Keywords】smart contract; blockchain; searchable encryption; attribute-based access control smart contract; blockchain; searchable encryption; attribute-based access control

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 理论模型

【DOI】 10.3390/electronics11162536

【Author】 Yan, Yu Lei, Yiming Wang, Yiming

【Source】AXIOMS

【影响因子】1.824

【主题类别】

区块链治理-市场治理-数字货币

【Abstract】A monetary model is established to introduce that bitcoin does have the characteristics of a price rise when the economic situation is terrible under high risk aversion. At this time, Bitcoin has the property of a safe-haven asset, and when economic conditions are good and risk aversion is low, Bitcoin has a pro-cyclical nature. At this time, Bitcoin has a stronger property as a medium of exchange. To show the movement law of the bitcoin price, we make a logarithmic linearization of the model and simulation, and the result is consistent with the theoretical analysis. To better understand the role of bitcoin in the real economy, several standard portfolio models are used to measure the similarities and differences between gold and bitcoin in an investment portfolio. After the outbreak of COVID-19, bitcoin has shown stronger safe-haven asset properties.

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【Keywords】cryptocurrency; COVID-19; hedging asset; monetary value; China U.S. stock market

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 观点阐述

【DOI】 10.3390/axioms11080415

【Author】 Hutson, James

【Source】SOCIETIES

【影响因子】0.000

【主题类别】

区块链应用-虚拟经济-元宇宙

【Abstract】Whereas traditional teaching environments encourage lively and engaged interaction and reward extrovert qualities, introverts, and others with symptoms that make social engagement difficult, such as autism spectrum disorder (ASD), are often disadvantaged. This population is often more engaged in quieter, low-key learning environments and often does not speak up and answer questions in traditional lecture-style classes. These individuals are often passed over in school and later in their careers for not speaking up and are assumed to not be as competent as their gregarious and outgoing colleagues. With the rise of the metaverse and democratization of virtual reality (VR) technology, post-secondary education is especially poised to capitalize on the immersive learning environments social VR provides and prepare students for the future of work, where virtual collaboration will be key. This study seeks to reconsider the role of VR and the metaverse for introverts and those with ASD. The metaverse has the potential to continue the social and workplace changes already accelerated by the pandemic and open new avenues for communication and collaboration for a more inclusive audience and tomorrow.

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【Keywords】virtual reality; introversion; neurodivergence; ASD; autism; metaverse; future of work

【发表时间】2022

【收录时间】2022-09-08

【文献类型】 观点阐述

【DOI】 10.3390/soc12040102

【Author】 Novak, Kae

【Source】TECHTRENDS

【影响因子】0.000

【主题类别】

区块链应用-虚拟经济-元宇宙

【Abstract】This article discusses how the term metaverse and the use of virtual worlds is not novel. Beginning with the use of the metaverse for learning starting in the 1990s, the author provides an overview of metaverse, immersion in virtual worlds, their use, and research conducted on them. The article ends with an outline of emerging trends and possible areas for additional exploration and engagement with AECT.

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【Keywords】Metaverse; Virtual worlds; Second Life; Virtual reality

【发表时间】

【收录时间】2022-09-08

【文献类型】 观点阐述

【DOI】 10.1007/s11528-022-00767-0

【Author】 Bommisetti, Ravi Kumar Raj, Bhavana K. Subbalakshmi, A. V. V. S. Shehryar, Muhammad Hoang, Sinh Duc

【Source】GLOBAL BUSINESS REVIEW

【影响因子】0.000

【主题类别】

区块链应用-虚拟经济-金融领域

【Abstract】Blockchain, which is at the heart of bitcoin and other digital currencies, is a game-changing technology, particularly in the stock market and financial technology. These characteristics make blockchain adoption appealing for enhancing information security, privacy and reliability in a variety of scenarios. This article develops the trust with reputation-based management for the financial stock market. Here distributed ledger technology (DLT) has been integrated for implementing the ledger in which data is stored across a network of decentralized nodes. By this, proof-based ledger has been maintained with transparency, traceability and security. DLT here used is based on trust design in mitigating the malicious activities of the financial stock marketing technology. Then using Bayesian theory based on the fault tolerance (BDLT_FT) model has been used in improving the efficiency of DLT and financial technology. This acts as the protocol which reduces energy consumption and enhance network scalability and security in digital transactions like cryptocurrency The financial data related to blockchain cryptocurrency were collected between the time period 2000 and 2020. The dataset of the stock market is evaluated under the fault tolerance model with statistical analysis. The statistical evaluation of financial data with developed BDLT_FT expressed that there is no association between the fault tolerance and the classification error.

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【Keywords】Blockchain; stock exchange market; financial technology; trust; DLT; BDLTFT

【发表时间】

【收录时间】2022-09-08

【文献类型】 实验仿真

【DOI】 10.1177/09721509221110371