Iman Supriadi, Wulandari Harjanti, Miya Dewi Suprihandari, Hendra Dwi Prasetyo · 5 authors
Blockchain is a promising technology for real-time accounting records and continuous monitoring. Blockchain innovation offers a technique for sharing data sources among individuals, also if they don't count on each other, and this produces a market for moving possessions based on peer-to-peer networks without a main authority. Blockchain innovation has drawn considerable financial investment from endeavor capitalists, multinational bankers, and the attention of regulators. This paper attempts to talk about the background from blockchain innovation, present use, and capacity applications that may enhance the timeliness, high quality, and precision from bookkeeping info. This paper will likewise assess the efficiency from some useful bookkeeping applications
Digitalization and Blockchain have fundamentally transformed the structure of the monetary system. The first wave of cryptocurrencies such as Bitcoin, Ethereum or Ripple have failed to gain relevance in terms of their share in monetary transactions. This was due to systemic deficiencies leading to extreme volatility, limited capacity and limited transparency, which have reduced their ability to fulfil the basic functions of money and hence their attractiveness as a medium of exchange. More recently, stable coins have entered the scene which were specifically designed to deal with the issue of volatility by tying the digital currency to an underlying set of assets. Hence the outlook for digital currencies has improved significantly. Although, the widespread of stable coins have has not been significant, the announcement of Facebook Libra and Telegram Gram with the huge number of billions of users raises the probability that this project will successfully reach global scale in a relatively short period of time. This means that a fully stable currency is made available to the people of developing countries, where governments are generally unable to manage the stability of their local currencies, which can lead to a digital dollarization. Meanwhile, the discussion around the introduction of central bank digital currencies (CBDC) as a possible response has continued more intensively. Introduction of a digital currency issued by the central bank will lead to a direct competition for bank deposits between Central Bank and Commercial banks which eventually lead banking system toward full reserve structure.
BACKGROUND: Personal health record (PHR) security, correctness, and protection are essential for health and medical services. Blockchain architecture can provide efficient data retrieval and security requirements. Exchangeable PHRs and the self-management of patient health can offer many benefits to traditional medical services by allowing people to manage their own health records for disease prevention, prediction, and control while reducing resource burdens on the health care infrastructure and improving population health and quality of life. OBJECTIVE: This study aimed to build a blockchain-based architecture for an international health record exchange platform to ensure health record confidentiality, integrity, and availability for health management and used Health Level 7 Fast Healthcare Interoperability Resource international standards as the data format that could allow international, cross-institutional, and patient/doctor exchanges of PHRs. METHODS: The PHR architecture in this study comprised 2 main components. The first component was the PHR management platform, on which users could upload PHRs, view their record content, authorize PHR exchanges with doctors or other medical health care providers, and check their block information. When a PHR was uploaded, the hash value of the PHR would be calculated by the SHA-256 algorithm and the PHR would be encrypted by the Rivest-Shamir-Adleman encryption mechanism before being transferred to a secure database. The second component was the blockchain exchange architecture, which was based on Ethereum to create a private chain. Proof of authority, which delivers transactions through a consensus mechanism based on identity, was used for consensus. The hash value was calculated based on the previous hash value, block content, and timestamp by a hash function. RESULTS: The PHR blockchain architecture constructed in this study is an effective method for the management and utilization of PHRs. The platform has been deployed in Southeast Asian countries via the Asia eHealth Information Network (AeHIN) and has become the first PHR management platform for cross-region medical data exchange. CONCLUSIONS: Some systems have shown that blockchain technology has great potential for electronic health record applications. This study combined different types of data storage modes to effectively solve the problems of PHR data security, storage, and transmission and proposed a hybrid blockchain and data security approach to enable effective international PHR exchange. By partnering with the AeHIN and making use of the network's regional reach and expert pool, the platform could be deployed and promoted successfully. In the future, the PHR platform could be utilized for the purpose of precision and individual medicine in a cross-country manner because of the platform's provision of a secure and efficient PHR sharing and management architecture, making it a reasonable base for future data collection sources and the data analytics needed for precision medicine.
With the gradual popularization of Internet-of-Things (IoT) applications and the development of wireless networking technologies, the use of heterogeneous devices and runtime verification of task fulfillment with different constraints are required in real-world IoT scenarios. As far as IoT systems are concerned, most of them are built on centralized architectures, which reveal various assailable points in data security and privacy threats. Hence, this paper aims to investigate these issues by delegating the responsibility of a verification monitor from a centralized architecture to a decentralized manner using blockchain technology. We present a smart contract-based task management scheme to provide runtime verification of device behaviors and allows trustworthy access control to these devices. The business logic of the proposed system is specified by the smart contract, which automates all time-consuming processes cryptographically and correctly. The usability of the proposed solution is further demonstrated by implementing a prototype application in which the Hyperledger Fabric is utilized to implement the business logic for runtime verification and access control with one desktop and one Raspberry Pi. A comprehensive evaluation experiment is conducted, and the results indicate the effectiveness and efficiency of the proposed system.
Otabek Sattarov, Azamjon Muminov, Cheol Won Lee, Hyun Kyu Kang · 8 authors
The net profit of investors can rapidly increase if they correctly decide to take one of these three actions: buying, selling, or holding the stocks. The right action is related to massive stock market measurements. Therefore, defining the right action requires specific knowledge from investors. The economy scientists, following their research, have suggested several strategies and indicating factors that serve to find the best option for trading in a stock market. However, several investors’ capital decreased when they tried to trade the basis of the recommendation of these strategies. That means the stock market needs more satisfactory research, which can give more guarantee of success for investors. To address this challenge, we tried to apply one of the machine learning algorithms, which is called deep reinforcement learning (DRL) on the stock market. As a result, we developed an application that observes historical price movements and takes action on real-time prices. We tested our proposal algorithm with three—Bitcoin (BTC), Litecoin (LTC), and Ethereum (ETH)—crypto coins’ historical data. The experiment on Bitcoin via DRL application shows that the investor got 14.4% net profits within one month. Similarly, tests on Litecoin and Ethereum also finished with 74% and 41% profit, respectively.
The achievements of west and central Africa in producing more than 60% of the world's cocoa, and sub-Saharan Africa's achievement in producing 13% of the world's cotton, hide child labor. These significant levels of production often involve child exposure to issues such as a lack of education; pesticides; dangerous farming tools; work accidents; human trafficking; etc. Blockchain offers an immutable register that allows for digital transactions, smart contract creation, as well as end-to-end product traceability. The main aim of this article is to provide an intelligent contract framework that protects child labor in farming while further enlightening understandings of adoption-related challenges. This framework considers conditions that farmer associations need to satisfy and gives them a tool to improve children's welfare. A research model for the adoption of this tool has been proposed and validated through surveys in the cotton and cacao sectors.
In the last year, the concept of distributed ledgers has entered mainstream company and policy agendas. Between different types of ledgers, it can be said that blockchain is the most notable. Different studies have shown that blockchain technology can reduce bureaucracy, increase the level of trust in public recordkeeping. In order to make further progress in its implementation in the different areas, it is necessary first of all that technological and ecosystem maturity of distributed ledgers have to increase in order to unlock the transformative power of blockchain; and in second instance the Policy agenda should focus on non-technological barriers, and create new administrative processes that can be re-engineered for blockchain. But, this new context, faces new legal challenges: personal data, free circulation of data..., which must to be analysed. The main objective of this paper is to analyse the new legal challenges from technical and methodological points of view.
Cryptocurrencies, such as Bitcoin, are becoming increasingly popular, having\nbeen widely used as an exchange medium in areas such as financial transaction\nand asset transfer verification. However, there has been a lack of solutions\nthat can support real-time price prediction to cope with high currency\nvolatility, handle massive heterogeneous data volumes, including social media\nsentiments, while supporting fault tolerance and persistence in real time, and\nprovide real-time adaptation of learning algorithms to cope with new price and\nsentiment data. In this paper we introduce KryptoOracle, a novel real-time and\nadaptive cryptocurrency price prediction platform based on Twitter sentiments.\nThe integrative and modular platform is based on (i) a Spark-based architecture\nwhich handles the large volume of incoming data in a persistent and fault\ntolerant way; (ii) an approach that supports sentiment analysis which can\nrespond to large amounts of natural language processing queries in real time;\nand (iii) a predictive method grounded on online learning in which a model\nadapts its weights to cope with new prices and sentiments. Besides providing an\narchitectural design, the paper also describes the KryptoOracle platform\nimplementation and experimental evaluation. Overall, the proposed platform can\nhelp accelerate decision-making, uncover new opportunities and provide more\ntimely insights based on the available and ever-larger financial data volume\nand variety.\n
Giorgio Alessandro Motta, Bedir Teki̇nerdoğan, Ioannis N. Athanasiadis
This study aims to investigate the application potential of blockchain technology in the agri-food industry, by following a case study approach focused on the early adopter companies. As the topic is emerging, there are not enough academic papers available to warrant a systematic literature review. To confirm this hypothesis and to inform to better understand guide this research, we first conducted a pre-literature review. Based on its outcomes, we formulated three research questions, and developed a protocol to identify case studies, and subsequently analyzed them to answer our questions. We identified and studied six case studies, in which blockchain has been used to address issues of trust and transparency, and to facilitate information sharing among agrifood chain stakeholders. While blockchain adoption is still in its infancy, governance issues are important, as broader partnerships are required for successful, sustainable applications.
Розглянуто вплив децентралізаці влади на управління системою фінансів місцевого самоврядування в Україні. Узагальнено та проаналізовано законодавчі акти в контексті децентралізації та визначено їх вплив фінансову систему країни. Проведено аналіз структури джерел надходжень місцевих бюджетів, їх динаміку. Встановлено збільшення державної підтримки місцевого та регіонального розвитку, зокрема значне зростання ресурсів Фонду регіонального розвитку, субвенцій на інфраструктуру та соціально-економічний розвиток об'єднаних територіальних громад (ОТГ). Запропоновано заходи для розв'язання комплексу проблем функціонування місцевих фінансів в умовах реформи децентралізації в найближчій перспективі, серед яких запровадження і розвиток на рівні центральної влади ефективного механізму моніторингу та ідентифікації проблем планування та виконання бюджету, підвищення рівня освіти керівництва громад, а також залучення громадськості до бюджетного процесу.
Hang Xiong, Tobias Dalhaus, Puqing Wang, Jiajin Huang
The blockchain is a ledger of accounts and transactions that are written and stored by all participants. It promises a reliable source of truth about the state of farms, inventories and contracts in agriculture, where the collection of such information is often incredibly costly. The blockchain technology can track the provenance of food and thus helps create trustworthy food supply chains and build trust between producers and consumers. As a trusted way of storing data, it facilitates the use of data-driven technologies to make farming smarter. In addition, jointly used with smart contracts, it allows timely payments between stakeholders that can be triggered by data changes appearing in the blockchain This article examines the applications of blockchain technology in food supply chains, agricultural insurance, smart farming, transactions of agricultural products for both theoretical and practical perspectives. We also discuss the challenges of recording transactions made by smallholder farmers and creating the ecosystem for utilizing the blockchain technology in the food and agriculture sector.
Blockchain, the technology behind the popular Bitcoin, is considered a "security by design" system as it is meant to create security among a group of distrustful parties yet without a central trusted authority. The security of blockchain relies on the premise of honest-majority, namely, the blockchain system is assumed to be secure as long as the majority of consensus voting power is honest. And in the case of proof-of-work (PoW) blockchain, adversaries cannot control more than 50% of the network's gross computing power. However, this 50% threshold is based on the analysis of computing power only, with implicit and idealistic assumptions on the network and node behavior. Recent researches have alluded that factors such as network connectivity, presence of blockchain forks, and mining strategy could undermine the consensus security assured by the honest-majority, but neither concrete analysis nor quantitative evaluation is provided. In this paper we fill the gap by proposing an analytical model to assess the impact of network connectivity on the consensus security of PoW blockchain under different adversary models. We apply our analytical model to two adversarial scenarios: 1) honest-but-potentially-colluding, 2) selfish mining. For each scenario, we quantify the communication capability of nodes involved in a fork race and estimate the adversary's mining revenue and its impact on security properties of the consensus protocol. Simulation results validated our analysis. Our modeling and analysis provide a paradigm for assessing the security impact of various factors in a distributed consensus system.
Technological advancements in the provision of financial services are transforming the economic landscape by providing opportunities for financial institutions, corporate sector, and consumers. Financial technologies (fintech) offer broader economic development and inclusive growth and facilitate international payments and remittances. Fintech applications, such as mobile wallets and crowdfunding that are hugely successful, especially in developing countries such as India, are examples of how simple technologies can enhance financial inclusion through the decentralized provision of payments, borrowings, and risk management. However, these innovations also create challenges for regulators. The emerging fintech models raise concerns on investor protection, adequacy of existing regulations and potential threats to financial stability, leading to questions on the policies and institutional framework required to tap into the benefits of these technologies securely. In this paper, we look at the landscape of fintech companies and their suitability for financing sustainable development. The paper also examines the policy and institutional frameworks required for the effective utilization of fintech for sustainable development. Fintech has the potential to involve the private sector to finance sustainable development and hence the paper would be of interest to policymakers, particularly in developing countries, as many struggles to bridge gaps in financing their sustainable development goals (SDGs)
The article gives a brief analysis of the place of a cryptocurrency in the system of objects of civil law rights. According to the results of the study, the authors conclude that it is incorrect to equate legal regimes of the cryptocurrency with the legal regime of virtual objects. The authors consider it promising to regulate legal features of the distributed ledger and register objects of civil law rights in the distributed ledger. A cryptocurrency is a means of payment that has no independent value. Thus, the mechanism of performance of obligations needs special elaboration. It is also noted that in the legal regulation of any social relations an essential role is assigned to the mechanisms and guarantees of restoration of violated rights and legitimate interests. To this end, the cryptocurrency regulation is inextricably linked with the institution of civil liability. The cryptocurrency combines the features of many civil law rights, but does not fully correspond to any of them. The assignment of the cryptocurrency to other property is possible within the framework of the current legislation without creating new objects of civil law rights, which can lead to conflicts and disputes concerning their legal regime.
Alesha Serada, Tanja Sihvonen, J. Tuomas Harviainen
This article analyzes specific characteristics of value created through digital scarcity and blockchain-proven ownership in cryptogames. Our object of study is CryptoKitties, the first instance of a blockchain-based game that has garnered media recognition and financial interest. The objective of this article is to demonstrate the limits of scarcity in value construction for owners of CryptoKitties tokens, manifested as breedable virtual cats. Our work extends the trends set out by earlier cryptocurrency studies from the perspective of cultural studies. For the purpose of this article, we rely on open blockchain analytics such as DappRadar and Etherscan, as well as player-created analytics, backed by a one-year-long participant observation period in the said game for research material. Combining theoretical cryptocurrency and Bitcoin studies, open data analysis, and virtual ethnography enables a grounded discussion on blockchain-based game design and play.
Data sharing techniques have progressively drawn increasing attention as a means of significantly reducing repetitive work. However, in the process of data sharing, the challenges regarding formation of mutual-trust relationships and increasing the level of user participation are yet to be solved. The existing solution is to use a third party as a trust organization for data sharing, but there is no dynamic incentive mechanism for data sharing with a large number of users. Blockchain 2.0 with smart contract has the natural advantage of being able to enable trust and automated transactions between a large number of users. This paper proposes a data sharing incentive model based on evolutionary game theory using blockchain with smart contract. The smart contract mechanism can dynamically control the excitation parameters and continuously encourages users to participate in data sharing.
Lewis Gudgeon, Daniel Pérez, Dominik Harz, Benjamin Livshits · 5 authors
The Global Financial Crisis of 2008, caused by the accumulation of excessive financial risk, inspired Satoshi Nakamoto to create Bitcoin. Now, more than ten years later, Decentralized Finance (DeFi), a peer-to-peer financial paradigm which leverages blockchain-based smart contracts to ensure its integrity and security, contains over 702m USD of capital as of April 15th, 2020. As this ecosystem develops, it is at risk of the very sort of financial meltdown it is supposed to be preventing. In this paper we explore how design weaknesses and price fluctuations in DeFi protocols could lead to a DeFi crisis. We focus on DeFi lending protocols as they currently constitute most of the DeFi ecosystem with a 76% market share by capital as of April 15th, 2020. First, we demonstrate the feasibility of attacking Maker's governance design to take full control of the protocol, the largest DeFi protocol by market share, which would have allowed the theft of 0.5bn USD of collateral and the minting of an unlimited supply of DAI tokens. In doing so, we present a novel strategy utilizing so-called flash loans that would have in principle allowed the execution of the governance attack in just two transactions and without the need to lock any assets. Approximately two weeks after we disclosed the attack details, Maker modified the governance parameters mitigating the attack vectors. Second, we turn to a central component of financial risk in DeFi lending protocols. Inspired by stress-testing as performed by central banks, we develop a stress-testing framework for a stylized DeFi lending protocol, focusing our attention on the impact of a drying-up of liquidity on protocol solvency. Based on our parameters, we find that with sufficiently illiquidity a lending protocol with a total debt of 400m USD could become undercollateralized within 19 days.
Envisioned to be the future of secured distributed systems, blockchain networks have received increasing attention from both the industry and academia in recent years. However, blockchain mining processes demand high hardware costs and consume a vast amount of energy (studies have shown that the amount of energy consumed in Bitcoin mining is almost the same as the electricity used in Ireland). To address the high mining cost problem of blockchain networks, in this paper, we propose a blockchain mining resources allocation algorithm to reduce the mining cost in PoW-based (proof-of-work-based) blockchain networks. We first propose an analytical queueing model for general blockchain networks. In our queueing model, transactions arrive randomly to the queue and are served in a batch manner with unknown service rate probability distribution and agnostic to any priority mechanism. Then, we leverage the Lyapunov optimization techniques to propose a dynamic mining resources allocation algorithm (DMRA), which is parameterized by a tuning parameter $K \gt 0$. We show that our algorithm achieves an $[O(1/ K),O(K)]$ cost-optimality-gap-vs-delay tradeoff. Our simulation results also demonstrate the effectiveness of DMRA in reducing mining costs.
The suitability of assets-backed money has been the subject of considerable debate, although hampered in part by lack of theoretical and empirical evidence. Therefore, the motivation of this research is to investigate the perceptions of Shari’ah scholars and financial experts on the concepts and salient features of Shari’ah-compliant precious metal backed crypto-currency (PMC). To achieve this, this study adopted a qualitative method using semi-structured interview based on saturation technique. The results from Shari’ah advisors and financial experts indicated that the informants have differences of views on the assets-backed money, but they agreed that it ensures stability of money and adding the cryptocurrency technology is found to be desirable and recommendable. It is also found that PMC would be subjected to financial regulation challenges and using blockchain technology will increase the transparency. The informants agreed that PMC is closer to Maqāsid al-Shari’ah and there is some form of justice and equality compared to the current interest-based financial system. Therefore, the informants recommended the implementation of PMC.
Silvia Valero, Francisco Climent, Rafael José Esteban de la Rosa
The banking sector has begun a process of digital transformation that is changing the way financial products and services are sold. This transformation is a consequence of the growing demand for digital channels by some sectors of the population, the progress of new technologies and the banks’ need to improve efficiency after the economic crisis. The emergence of innovative financial technology (fintech) startups in the banking sector has been the lever initiating this digital transformation. Technology companies are challenging established banking business models and promoting the democratisation of finance in a more efficient and transparent financial ecosystem. Increasing investment in these technology companies has also attracted the interest of various regulators, and the future suggests a scenario of collaboration between these new players and traditional companies, with a consequently difficult task for the regulators of guaranteeing the same conditions of competition for new entrants and incumbents. However, technology companies with vast experience in the gathering and use of data from millions of users (such as Amazon, Google or Facebook) are considered a threat. Moreover, some types of evolving fintechs, such as neobanks with bank licences, may also become competitors. Distributed ledger technology (DLT) or blockchain, a fintech technology that is evolving constantly, has already awoken the interest of all financial sector participants because it could trigger real disruption and produce a new era of value.