ABSTRACT
PurposeThe COVID-19 pandemic has led to global economic policy uncertainty, which has increased the need to investigate ways to mitigate the uncertainty. This study aims to examine the potential of cryptocurrencies as a hedge and safe haven avenue against economic policy uncertainty.Design/methodology/approachThis study investigates the behavior of the five leading cryptocurrencies in relation to country-level and group-level economic policy uncertainty indices, as measured by the text-based method developed by Baker et al. (The Quarterly Journal of Economics, 2016, 131, 1593-1636). The research covers a broad range of emerging and developed economies from July 2013 to September 2020. The study employs the approach of Narayan et al. (Economic Modelling, 2016, 53, 388-397) to examine the hedging and safe-haven properties of cryptocurrencies.FindingsThis study finds that the top cryptocurrencies play a hedging role against economic policy uncertainty, with some exceptions. Additionally, there is evidence to support the idea that cryptocurrencies can serve as a safe haven during the COVID-19 pandemic. As a result, investors may benefit from using cryptocurrencies as a risk-management avenue during times of uncertainty.Originality/valueThis research contributes to the existing literature by testing the cryptocurrencies' hedging and safe haven properties in a new way, by analyzing their lead and lag behaviors using a recent and innovative approach. Additionally, it examines a wide range of emerging and advanced markets, providing insight into the potential of using cryptocurrencies as a risk mitigation avenue.
ABSTRACT
With the explosion of COVID-19 cases and the government's needs to control virus spreading, the development of effective and robust systems for managing vaccination certificates to restrict citizens' activities has been in the centre of many governments. This paper proposes a system that allows for the update of the status of certificates and bases its function on a specific form of logs stored on Blockchains and a set of rules for the interpretation of these logs. Also an outline of a proof of concept implementation of the system in Ethereum together with a cost and security analysis are provided in the paper. The proposed architecture provides several benefits with the most prominent one being the suspension of certificates in case an already vaccinated individual is found positive. In existing certificate management systems a vaccinated individual that is tested positive still holds a valid vaccination certificate during the self-isolation period. This vulnerability allows infected individuals to commute freely and thus facilitates the spread of the pandemic. The proposed solution is not limited to COVID-19 related certificates, but rather it could be deployed in any kind of digital certificate. © 2022 ACM.
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Interest in leveraging blockchain technology to boost healthcare and e-health solutions has lately increased. Blockchain has proven to have enormous promise in a range of e-health industries because of its decentralized and reliable nature, including the secure exchange of electronic health records (EHRs) and database access management among numerous medical entities. A unique paradigm known as the "patient-centric approach” places the patient at the center of the healthcare system and gives them complete control over who has access to and can share their personal health information. Strong confidentiality and safety requirements are necessary for health information. Additionally, other concerns must be resolved, such as secrecy, interoperability, scalability, cost-effectiveness, and timeliness. This paper offers a patient-centric privacy-preserving framework for an efficient and safe medical record to address these problems. Based on three parameters transaction cost, execution time, and gas cost. Three blockchain platforms are compared by using the smart contract to find out the suitable platform for the implementation of this framework. Blockchain platforms served as a benchmark for the performance assessment of a designed framework. Although blockchain will not fix every issue in healthcare organizations, it will undoubtedly assist in dramatically reducing some of the most critical ones.
ABSTRACT
PurposeThe purpose of this research is to analyze the Bitcoin (BTC) and Ether (ETH) long memory and conditional volatility.Design/methodology/approachThe empirical approach includes ARFIMA-HYGARCH and ARFIMA-FIGARCH, both models under Student‘s t-distribution, during the period (ETH: November 9, 2017 to November 25, 2021 and BTC: September 17, 2014 to November 25, 2021).FindingsFindings suggest that ARFIMA-HYGARCH is the best model to analyze BTC volatility, and ARFIMA-FIGARCH is the best approach to model ETH volatility. Empirical evidence also confirms the existence of long memory on returns and on BTC volatility parameters. Results evidence that the models proposed are not as suitable for modeling ETH volatility as they are for the BTC.Originality/valueFindings allow to confirm the fractal market hypothesis in BTC market. The data confirm that, despite the impact of the Covid-19 crisis, the dynamics of BTC returns, and volatility maintained their patterns, i.e. the way in which they evolve, in relation to the prepandemic era, did not change, but it is rather reaffirmed. Yet, ETH conditional volatility was more affected, as it is apparently higher during Covid-19. The originality of the research lies in the focus of the analysis, the proposed methodology and the variables and periods of study.
ABSTRACT
Since Bitcoin introduced the blockchain, research has been conducted to expand its use cases beyond finance. One sector where blockchain is anticipated to have a big influence is healthcare. Researchers and practitioners in health informatics constantly struggle to keep up with the advancement of this field's young but quickly expanding body of research. This chapter provides a thorough review of studies carried out to demonstrate the benefits of blockchain technology that have been utilized in the domain of healthcare, in addition to the pandemic, COVID-19, which led to a massive and pervasive repercussion on healthcare and has significantly accelerated the implementation of digital technology. This chapter also depicts how researchers have presented the use cases for adopting Blockchain technology in the healthcare sector. The state-of-the-art blockchain application development for healthcare has also been described in this chapter, along with any inadequacies and potential future study topics. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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In this paper, we study how the comovement between cryptocurrencies and the U.S. inflation expectation rates has changed during the post-reopening of the U.S. economy after the Covid-19 crisis. To do so, we develop a new concept of "exceedance co-kurtosis” which allows us to quantify asymmetry in strong comovement between each cryptocurrency and the inflation expectation rate. The key findings are as follows. First, we show the change in the co-kurtosis asymmetry for major cryptocurrencies: the downside co-kurtosis was higher than the upside co-kurtosis but it decreased after the reopening of the economy. Although the unconditional correlations between cryptocurrencies and the inflation expectation rates remain very low, our results indicate that the major cryptocurrencies become a slightly better inflation hedge after the reopening. Second and more interestingly, the results do not depend on whether a cryptocurrency has a cap on maximum supply or not. Therefore, treating the major cryptocurrencies as digital commodities could be misleading from the viewpoint of portfolio optimization. © 2023
ABSTRACT
Trust is essential in the digital world. It is a critical task to build digital trust for the ongoing digital engineering transformation. Aiming at developing a blockchain-based digital trust mechanism for Cloud Manufacturing or Manufacturing-as-a-Service (MaaS), in this paper, we use the manufacturing of low dead space (LDS) medical syringes through Cloud Manufacturing as a motivating scenario to develop a basic framework. To meet the need of optimally saving COVID-19 vaccine doses to save more lives, the medical device manufacturing community needs to make a swift move to meet the surged need for LDS syringes. Cloud Manufacturing is a form of emerging Digital Manufacturing facilitated with Cloud/Edge Computing, the Internet of Things, and other digital technologies. Cloud manufacturing allows quickly establishing a digital virtual enterprise that pools together various manufacturing resources worldwide to meet the surged needs of products and save cost and time. Trusting the product quality and safety is a significant challenge when using Cloud Manufacturing to manufacture the products. This paper proposes a schema of blockchain-based digital trust mechanisms with examples of using Cloud Manufacturing of medical LDS syringes for the urgent needs of catering COVID-19 vaccination. [ABSTRACT FROM AUTHOR] Copyright of Journal of Integrated Design & Process Science is the property of IOS Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
ABSTRACT
Trust is essential in the digital world. It is a critical task to build digital trust for the ongoing digital engineering transformation. Aiming at developing a blockchain-based digital trust mechanism for Cloud Manufacturing or Manufacturing-as-a-Service (MaaS), in this paper, we use the manufacturing of low dead space (LDS) medical syringes through Cloud Manufacturing as a motivating scenario to develop a basic framework. To meet the need of optimally saving COVID-19 vaccine doses to save more lives, the medical device manufacturing community needs to make a swift move to meet the surged need for LDS syringes. Cloud Manufacturing is a form of emerging Digital Manufacturing facilitated with Cloud/Edge Computing, the Internet of Things, and other digital technologies. Cloud manufacturing allows quickly establishing a digital virtual enterprise that pools together various manufacturing resources worldwide to meet the surged needs of products and save cost and time. Trusting the product quality and safety is a significant challenge when using Cloud Manufacturing to manufacture the products. This paper proposes a schema of blockchain-based digital trust mechanisms with examples of using Cloud Manufacturing of medical LDS syringes for the urgent needs of catering COVID-19 vaccination. © 2023 - The authors. Published by IOS Press.
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The covid-19 crisis has severely affected the dynamics of the real estate sector, which is facing various financial and structural problems. The current real estate world is complicated by the lack of transparency in transactions such as rental, purchase, and sale, and it does not reach the level of confidentiality and authenticity of operational data. In addition, real estate financing brings together several players such as banks, notaries, and others, which makes the acquisition of real estate very expensive. With the advent of blockchain technology, many fields such as finance, accounting, and real estate have received a positive impact using the benefits of this technology. This article aims to reorganize real estate into a next-generation digitized system based on blockchain technology, by proposing a crowdfunding model that aims to eliminate intermediate, costs. Moreover, this model can allow to customers, who do not have immediate financing, the possibility of acquiring real estate. We also present the implementation of this model through smart contracts and the blockchain to set up a decentralized platform that ensures the security, traceability, and transparency of transactions. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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This paper proposes and emphasizes the requirement of an Blockchain based smart contract for NGO's and startup crowdfunding in the present circumstances. It also highlights the need of an online financial system for indigenous NGO's and seed fund utilization of startups. Conventionally, most charity organizations make use of hard cash for settling its transactions making the process less transparent. However, due to the COVID-19 pandemic, financial system has been largely affected. In this case an online financial transaction cum procurement portal would be crucial for the candidates applying relief in remote locations. The system analyses their eligibility based on their Curriculum Vitae (CV). Proposed system uses Ethereum based smart contract and Truffle Box to build a complete Dapp (decentralized application). Authors have used MetaMask Extension as a cryptocurrency wallet and Ganache blockchain to develop, deploy and test the decentralized application. © 2022 IEEE.
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We use transaction data on CryptoPunks to dissect the factors affecting the returns of non-fungible tokens (NFTs). Our results show that trading volume in the short period before a trader buys (sells) CryptoPunk relates negatively (positively) to the returns on NFTs, suggesting that when market trading volume is at a high level, NFT owners are better off on the sell side, and investors interested in NFTs should avoid joining the herd. Turnover of a token tends to harm its returns. Finally, both traders' willingness to purchase and trading experience have a positive impact on NFT returns within short-term investment horizons. © 2023 Elsevier Inc.
ABSTRACT
Social distancing has been imposed to prevent substantial transmission of the COVID-19 outbreak, which is presently a global public health issue. Medical healthcare providers rely on telemedicine to monitor their patients, particularly those with chronic conditions. However, telemedicine faces many implementation-related risks, including data breaches, access restrictions within the medical community, inaccurate diagnosis, fraud, etc. The authors propose a transparent, tamper-proof, distributed, decentralized smart healthcare system (DSHS) that uses blockchain-based smart contracts. The authors use an immutable modified Merkel tree structure to hold the transaction for viewing contracts on a public blockchain, updating patient health records (PHR), and exchanging PHR to all entities. It is verified by a performance evaluation based on the Ethereum platform. The simulation results show that the proposed system outperforms existing approaches by enhancing transparency, boosting efficiency, and reducing average latency in the system. The proposed system improves the functionality of the SHS environment.
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The coronavirus pandemic caused global health and economic disruption of an unknown scale. Several issues with the pharmaceutical supply chain such as the counterfeiting of drugs came to light in these dire times. While continual efforts are being applied in order to effectively treat and annihilate the coronavirus, so are the efforts of supply chains to prepare for patient care in case of a recurrence. The requirement of superior quality medicines has sky rocketed, subsequently, so has the influx of counterfeited drugs. The security of the pharmaceutical supply chain is unquestionably necessary due to the large scale increase in demand for drugs. Tampering of the supply chain is not easily detectable when unethical practices are suspected currently. A radical and innovative method that contains the potential to overcome the challenges of securing the pharmaceutical supply chain is the blockchain technology. So, our proposed solution amalgamates blockchain technology into the drug supply chain to make it tamper-proof. This study proposes a system that harnesses blockchain's properties to ensure supply of safe and traceable pharmaceuticals from end to end. The smart contracts designed have been deployed on a local blockchain using Ganache. Results of our experimentation indicate with certainty that not only is this solution feasible but it is more secure than the present day scenario of the pharmaceutical supply chain. © 2022 IEEE.
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During any emergency, a donation is considered a moral responsibility all over the globe. The lack of transparency and oversight in charity donations hurts people’s enthusiasm to donate. Donors are distrustful about how their funds are utilized. The use of blockchain technology (BCT) will provide a solution to make the donation procedure more viable. It is a distributed technology that offers a secure and transparent environment by avoiding the involvement of third parties between contributors and charities. This article proposed a blockchain-based donation mechanism for the convenience of charity organizations, donors, and beneficiaries during disasters, pandemics such as Covid-19, and other emergencies. All transactions can be traced in blockchain, giving donors visibility into where and how their funds are utilized. This article contributes to improving donations’openness to strengthen public interest in donations and encourage BCT in charity. Ethereum blockchain is used to implement the proposed framework and provides a convenient donation platform. Smart contracts are used to make donations, which build trust between contributors, beneficiaries, and charity organizations. The blockchain-based donation method saves time, lowers donation costs, and eliminates the chances of dubious campaign funds. This study will contribute to improving emergency recovery efforts. IEEE
ABSTRACT
We use transaction data on CryptoPunks to dissect the factors affecting the returns of non-fungible tokens (NFTs). Our results show that trading volume in the short period before a trader buys (sells) CryptoPunk relates negatively (positively) to the returns on NFTs, suggesting that when market trading volume is at a high level, NFT owners are better off on the sell side, and investors interested in NFTs should avoid joining the herd. Turnover of a token tends to harm its returns. Finally, both traders' willingness to purchase and trading experience have a positive impact on NFT returns within short-term investment horizons.
ABSTRACT
During any emergency, a donation is considered a moral responsibility all over the globe. The lack of transparency and oversight in charity donations hurts people's enthusiasm to donate. Donors are distrustful about how their funds are utilized. The use of blockchain technology (BCT) will provide a solution to make the donation procedure more viable. It is a distributed technology that offers a secure and transparent environment by avoiding the involvement of third parties between contributors and charities. This article proposed a blockchain-based donation mechanism for the convenience of charity organizations, donors, and beneficiaries during disasters, pandemics such as Covid-19, and other emergencies. All transactions can be traced in blockchain, giving donors visibility into where and how their funds are utilized. This article contributes to improving donations' openness to strengthen public interest in donations and encourage BCT in charity. Ethereum blockchain is used to implement the proposed framework and provides a convenient donation platform. Smart contracts are used to make donations, which build trust between contributors, beneficiaries, and charity organizations. The blockchain-based donation method saves time, lowers donation costs, and eliminates the chances of dubious campaign funds. This study will contribute to improving emergency recovery efforts.
ABSTRACT
Social distancing has been imposed to prevent substantial transmission of the COVID-19 outbreak, which is presently a global public health issue. Medical healthcare providers rely on telemedicine to monitor their patients, particularly those with chronic conditions. However, telemedicine faces many implementation-related risks, including data breaches, access restrictions within the medical community, inaccurate diagnosis, fraud, etc. The authors propose a transparent, tamper-proof, distributed, decentralized smart healthcare system (DSHS) that uses blockchain-based smart contracts. The authors use an immutable modified Merkel tree structure to hold the transaction for viewing contracts on a public blockchain, updating patient health records (PHR), and exchanging PHR to all entities. It is verified by a performance evaluation based on the Ethereum platform. The simulation results show that the proposed system outperforms existing approaches by enhancing transparency, boosting efficiency, and reducing average latency in the system. The proposed system improves the functionality of the SHS environment. © 2022 Taru Publications. All rights reserved.
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This study aims to examine whether the prices and returns of two cryptocurrencies, Dogecoin and Ethereum, are affected by Twitter engagement following the COVID-19 pandemic. We use the autoregressive integrated moving average with explanatory variables model to integrate the effects of investor attention and engagement on Dogecoin and Ethereum returns using data from December 31, 2020, to May 12, 2021. The results provide evidence supporting the hypothesis of a strong effect of Twitter investor engagement on Dogecoin returns; however, no potential impact is identified for Ethereum. These findings add to the growing evidence regarding the effect of social media on the cryptocurrency market and have useful implications for investors and corporate investment managers concerning investment decisions and trading strategies.
ABSTRACT
PurposeThe purpose of this research is to analyze the Bitcoin (BTC) and Ether (ETH) long memory and conditional volatility. Design/methodology/approachThe empirical approach includes ARFIMA-HYGARCH and ARFIMA-FIGARCH, both models under Student's t-distribution, during the period (ETH: November 9, 2017 to November 25, 2021 and BTC: September 17, 2014 to November 25, 2021). FindingsFindings suggest that ARFIMA-HYGARCH is the best model to analyze BTC volatility, and ARFIMA-FIGARCH is the best approach to model ETH volatility. Empirical evidence also confirms the existence of long memory on returns and on BTC volatility parameters. Results evidence that the models proposed are not as suitable for modeling ETH volatility as they are for the BTC. Originality/valueFindings allow to confirm the fractal market hypothesis in BTC market. The data confirm that, despite the impact of the Covid-19 crisis, the dynamics of BTC returns, and volatility maintained their patterns, i.e. the way in which they evolve, in relation to the prepandemic era, did not change, but it is rather reaffirmed. Yet, ETH conditional volatility was more affected, as it is apparently higher during Covid-19. The originality of the research lies in the focus of the analysis, the proposed methodology and the variables and periods of study.
ABSTRACT
The COVID-19 pandemic caused disruption in the healthcare market, which resulted in shortages of essential healthcare products. The pandemic exacerbated the problems that already existed in the healthcare supply chain, such as poor data availability, transparency, and accessibility. Such problems necessitate the introduction of a solution that is capable of managing products, maintaining ownership, facilitating trading, and delivering products in a traceable, auditable, and trustworthy manner. In this article, we propose a nonfungible-token-based solution for the management of healthcare products, where the ownership of a product is maintained by using digital certification, the trade and delivery of healthcare products is facilitated by a smart contract, and disputes are settled by an arbitrator while keeping all related information on-chain for auditing purposes. We utilize the Interplanetary File System to store the metadata of healthcare products to avoid storing large-sized data on the blockchain. We present system diagrams and algorithms along with the implementation details. We conduct security testing to demonstrate that our solution is resilient and secure against common vulnerabilities and exploits. We compare our solution with the existing solutions to show its distinctive features and novelty. The smart contracts code is made publicly available on GitHub. Author