Bu çalışmada ekonomik politika belirsizliğinin (EPU) kripto paralar üzerindeki etkisi panel veri yöntemleriyle araştırılmaktadır. Bu amaç doğrultusunda öncelikle küresel ekonomik politika belirsizliği endeksi ve en büyük dört kripto paranın aylık verileri elde edilmiştir. Çalışmada kullanılan kripto paralar; Bitcoin (BTC), Ethereum (ETH), BinanceCoin (BNB) ve Ripple (XRP)’dir. 2018:01-2020:12 dönemine ait verilerin kullanıldığı çalışmada, yatay kesit bağımlılığı ve homojenlik testleri gerçekleştirilmiştir. Daha sonra Kónya (2006) tarafından önerilen bootstrap panel nedensellik testi uygulanmıştır. Dört kripto paradan ilk sırada yer alan Bitcoin ile EPU arasında çift yönlü nedensellik ilişkisi bulunurken, son sırada bulunan XRP için herhangi bir nedensellik ilişkisine rastlanamamıştır. İkinci ve üçüncü sıradaki kripto paralarda ise EPU’dan bu paralara doğru tek yönlü nedensellik ilişkisi olduğu görülmüştür. Çalışmadan elde edilen bulgular, ekonomik politika belirsizliğinin kripto paraların değerleri üzerinde etkisi olabileceğini göstermektedir.
This paper discusses the blockchain frameworks for evaluating trustworthiness in managing waqf management system. The frameworks are Ethereum, Hyperledger, Finterra Waqfchain and Waqf Blockchain (WB). The invention of the blockchain has offered many benefits to the waqf institution since this institution faced many challenges such as lack of data transparency, accountability issues, weak of historical records, improper audit and improper compliance practices that may breaks donors' trust to use waqf system as a platform to make donation. However, the framework has their own pros and cons in order to make waqf management system more transparent, trusted and efficient. As a result, Ethereum framework shows the most suitable blockchain platform that can be used for the waqf management system.
Abstract Since the introduction of Ethereum in 2015, blockchain technology (BT) has been evolving, and BT has been associated with the concept of the sharing economy by business academics. Despite the marketing research on the sharing economy that has been extensively conducted in the last decade, the linkage between BT and ethical marketing in the sharing economy remains unclear. Through a systematic literature review of 163 articles and a co-citation analysis, this study identifies the key elements of blockchain capabilities, blockchain attributes, and the underlying economic theories of blockchain. It also synthesizes and proposes a shift of ethical marketing logic in the blockchain-based sharing economy that delineates the principles of stakeholder capitalism. The article concludes with a list of future research directions that underline three approaches of stakeholder theory (i.e., the descriptive, instrument, and normative approaches). These directions aim to guide marketing scholars concerning how BT enables an institutionally embedded view of ethical marketing activities and practices that enhance collaborative marketing and subsequently innovate value chains and create sustainable business models in the sharing economy, as well as to the metaverse.
Matija Šipek, Martin Žagar, Nikola Drašković, Branko Mihaljević
Blockchain technology provides a private, secure, transparent decentralized exchange of data. Also, blockchain is not limited to a particular area, but it has a wide range of applications and can be integrated into a variety of Internet interactive systems. For example, the Internet of Things (IoT), supply chain tracking, Electronic Health Records (EHR), digital forensics, identity management, trustless payments, and other key business elements will all benefit from its implementation. Next layer solutions such as Ethereum 2.0, Polkadot, Cardano, and other Web 3.0 technologies provide developers versatility. Moreover, these platforms utilize smart contracts which are similar to standard, traditionalized software during development but offer key utilities to end-users such as online wallets, secure data with transparent rules. Blockchain is receiving a lot of attention in educational technology (EduTech) as it aims to achieve a more transparent and multipurpose educational system. In addition to smart contract technology which defines how data should be registered, gathered and processed, blockchain can be used as an IoT intermediary for mobile usage. Therefore, we implemented an educational learning platform powered by blockchain technology to examine feasibility in industry and academic environment. In essence, this is a web application which is adapted to mobile platform and connected to blockchain for crucial data exchanges. In this paper we want to emphasize the potential of blockchain technology in multiple sectors as well as the need to really understand the underlying principles which are allowing disruptability of traditional centralized software solutions.
Mirza Jabbar Aziz Baig, M. Tariq Iqbal, Mohsin Jamil, Jahangir Khan · 5 authors
With advancements in renewable energy technologies, consumers are becoming prosumers, and renewable energy resources are being used in distributed networks. In an isolated distributed system, peer-to-peer (P2P) energy trading is one of the most promising energy management solutions. In this paper, we propose a P2P energy trading method for micro-grids using open resources and technology. The proposed setup comprises an Internet of Things (IoT) server to transfer energy amongst the peers without human intervention, and an Ethereum based private blockchain is suggested for money transfer in the form of cryptocurrency. The IoT server enables the peers to control and monitor self-produced energy. Arduino UNO, ACS 712 hall-effect current sensor, and a relay are the main components used in the hardware setup. The current sensor data is sent in real- time to Arduino for onward communication to the IoT server. A user-friendly interface has been developed on the server to perform various energy trading tasks. Peers have the choice to access the server remotely to perform energy trading tasks. The energy trading events can be shared amongst peers through e-mail notifications. For financial transactions, we utilized Ganache graphical user interface (GUI) a private Ethereum blockchain eliminating the need for financial institutions. The proposed peer-to-peer energy trading model has been successfully tested for energy trading between two peers. This paper provides details of the proposed hardware and software setup and explains how low-cost P2P energy trading can be achieved.
AI applications find widespread use in a variety of domains. For further acceptance, mostly when multiple agents interact with the system, we must aim to preserve the privacy of participants information in such applications. Towards this, the Yao’s Millionaires’ problem (YMP), i.e., to determine the richer among two millionaires’ privately, finds relevance. This work presents a novel, practical, and verifiable solution to YMP, namely, Secure Comparison Protocol (SCP). We show that SCP achieves this comparison in a constant number of rounds, without using encryption and not requiring the participants’ continuous involvement. SCP uses semi-trusted third parties - which we refer to as privacy accountants - for the comparison, who do not learn any information about the values. That is, the probability of information leak is negligible in the problem size. In SCP, we also leverage the Ethereum network for pseudo-anonymous communication, unlike computationally expensive secure channels such as Tor. We present a Secure Truthful cOmbinatorial aUction Protocol (STOUP) for single-minded bidders to demonstrate SCP’s significance. We show that STOUP, unlike previous works, preserves the privacies relevant to an auction even from the auctioneer. We demonstrate the practicality of STOUP through simulations.
In this article, we present a Social Network Analysis–based approach to investigate user behaviour during a cryptocurrency speculative bubble in order to extract knowledge patterns about it. Our approach is general and can be applied to any past, present and future cryptocurrency speculative bubble. To verify its potential, we apply it to investigate the Ethereum speculative bubble happened in the years 2017 and 2018. We also describe several interesting knowledge patterns about the behaviour of specific categories of users that we obtained from this investigation. Furthermore, we describe how our approach can support the construction of an identikit of the speculators who maneuvered behind the Ethereum bubble analysed. Finally, we show that this capability of supporting the hunting for speculators is intrinsic of our approach and can cover past, present and future bubbles.
Comprendre la consommation énergétique des blockchains : un regard sur les contrats intelligents Les systèmes de chaînes de blocs sont des registres répliqués dans un réseau pair à pair. Elles ont connu un développement rapide depuis quelques années en s'illustrant dans de nombreux domaines d'activités. En permettant le traitement et la sauvegarde de données dans un contexte distribué et Byzantin, ces technologies ont le potentiel de modifier de nombreux secteurs. Par exemple, dans le cadre de la finance décentralisée, les cryptomonnaies se développement comme une alternative aux monnaies fiduciaires en proposant un système de paiement dépourvu de tiers de confiance. Cependant, une certaine inquiétude vis-à-vis de l’impact environnemental des chaînes de blocs a émergé en parallèle de leur développement. En particulier, de nombreuses recherches ont démontré le coût énergétique important des chaînes basées sur les preuves de travail. Dans cette thèse, nous proposons de contribuer à l'étude expérimentale du coût énergétique des solutions logicielles basées sur les chaînes de blocs. Face à l'enrichissement progressif de l'écosystème lié aux chaînes de blocs, nous proposons BCTMark, un nouvel outil de déploiement et d'évaluation des performances des chaînes de blocs. Partant de cet outil, nous concentrons notre étude sur l'impact des contrats intelligents sur la chaîne de blocs Ethereum. D'une part, nous proposons un modèle pour l'estimation du coût énergétique des contrats intelligents développé pour Ethereum. D'autre part, nous proposons un nouveau protocole pour l'identification et l'élimination des contrats non utilisés dans le but de proposer des chaînes de blocs plus frugales en calculs et espaces de stockages.
Recent research and publications. A blockchain is a distributed data structure that is replicated and distributed among network members. The first blockchain specification was proposed together with the digital currency Bitcoin in 2008 by a man under the pseudonym Satoshi Nakamoto to solve the problem of centralizing finances around banks. Today, block-chains are used mainly in the field of decentralized finance (DeFi) in the form of cryptocur-rencies and instruments to them. There are also a few specialized foreign studies on the use of blockchain in the monitoring of supplies, but these studies are more focused on the economic and logistical feasibility of using the blockchain in supply chains, without the exact models of information systems on which such a system should work. The aim of the study. Study of blockchain technology in information systems for moni-toring the movement of goods and resources, which can improve the processes of tracking and automation in supply chains. Main material of the study. The paper develops a prototype of the information system for monitoring the movements of goods in supply chains, which is working above the Ethereum virtual machine. The system is working using two smart-contracts and the paper describes the exact structure and specification of smart-contracts and principles of communication between them for the information system for monitoring the movements of goods. Conclusions. The article presents a prototype of an information system using blockchain technology and smart contracts which are working on the Ethereum network. Based on prototyping of the information system for monitoring the movements of goods, it was concluded that the transparency of the tracking and automation process in supply chains is improved. This work is useful for designing and creating more detailed and sophisticated systems for monitoring and managing the movement of goods and other supplies based on the use of Blockchain technology.
A virtual asset is a type of asset which does not have a material representation, although its value is reflected in a real currency. Due to their nature, the price of digital assets is usually highly volatile, especially with futures, which are derivative financial contracts. This is the most important contributing factor to the problem of the low usability of digital-based contracts in enterprise operations.Previously existing virtual assets included photography, logos, illustrations, animations, audiovisual media, etc. However, virtually all of such assets required a third-party platform for exchange to currency. The necessity of having a trusted by both sides mediator greatly limited the ease of use, and ultimately restricted the number of such transactions. Still, popularity of digital assets only grew, as evidenced by an explosive growth of software applications in the 2000s, as well as blockchain-based asset space in the 2010s.The newest and most promising solution developed is based on cryptoassets. Underlying usage of block- chain technology for the transactions checking and storage ensures clarity in virtual assets’ value history. Smart contracts written for the Ethereum platform, as an example, provide a highly trustful way of express- ing predefined conditions of a certain transaction. This allows safe and calculated enterprise usage, and also eliminates the need of having a mutually trusted third-party. The transactions are fully automated and happen at the same time as the pre-defined external conditions are met.Ethereum was chosen as an exemplary platform due to its high flexibility and amount of existing development. Even now, further advancements are being explored by its founder and community. Besides Ether, it is also used nоn-fungible tokens, decentralized finance, and enterprise blockchain solutions. Another important point is how much more nature friendly it is compared to main competitors, due to energy-efficiency of the mining process, enforced by the platform itself. This makes it ideal for responsible usage as well as further research.This article explores the digital assets usage, as well as explains cryptoassets technological background, in order to highlight the recent developments in the area of futures based on virtual assets, using certain Ether implementation as an example, which offers perpetual futures.
Anwar Said, Muhammad Umar Janjua, Saeed‐Ul Hassan, Zeeshan Muzammal · 8 authors
Ethereum, the second-largest cryptocurrency after Bitcoin, has attracted wide attention in the last few years and accumulated significant transaction records. However, the underlying Ethereum network structure is still relatively unexplored. Also, very few attempts have been made to perform link predictability on the Ethereum transactions network. This paper presents a Detailed Analysis of the Ethereum Network on Transaction Behavior, Community Structure, and Link Prediction (DANET) framework to investigate various valuable aspects of the Ethereum network. Specifically, we explore the change in wealth distribution and accumulation on Ethereum Featured Transactional Network (EFTN) and further study its community structure. We further hunt for a suitable link predictability model on EFTN by employing state-of-the-art Variational Graph Auto-Encoders. The link prediction experimental results demonstrate the superiority of outstanding prediction accuracy on Ethereum networks. Moreover, the statistic usages of the Ethereum network are visualized and summarized through the experiments allowing us to formulate conjectures on the current use of this technology and future development.
Health insurance plays a significant role in ensuring quality healthcare. In response to the escalating costs of the medical industry, the demand for health insurance is soaring. Additionally, those with health insurance are more likely to receive preventative care than those without health insurance. However, from granting health insurance to delivering services to insured individuals, the health insurance industry faces numerous obstacles. Fraudulent actions, false claims, a lack of transparency and data privacy, reliance on human effort and dishonesty from consumers, healthcare professionals, or even the insurer party itself, are the most common and important hurdles towards success. Given these constraints, this chapter briefly covers the most immediate concerns in the health insurance industry and provides insight into how blockchain technology integration can contribute to resolving these issues. This chapter finishes by highlighting existing limitations as well as potential future directions.
Marco Ortu, Stefano Vacca, Giuseppe Destefanis, Claudio Conversano
We analyse, using a mixture of statistical models and natural language process techniques, what happened in social media from June 2019 onwards to understand the relationships between Cryptocurrencies’ prices and social media, focusing on the rise of the Bitcoin and Ethereum prices. In particular, we identify and model the relationship between the cryptocurrencies market price changes, and sentiment and topic discussion occurrences on social media, using Hawkes’ Model. We find that some topics occurrences and rise of sentiment in social media precedes certain types of price movements. Specifically, discussions concerning governments, trading, and Ethereum cryptocurrency as an exchange currency appear to negatively affect Bitcoin and Ethereum prices. Those concerning investments, appear to explain price rises, whilst discussions related to new decentralized realities and technological applications explain price falls. Finally, we validate our model using a real case study: the already famous case of ”Wallstreetbet and GameStop”1 that took place in January 2021.
Youcef Maouchi, Lanouar Charfeddine, Ghassen El Montasser
This paper investigates digital financial bubbles amidst the COVID-19 pandemic. Using a sample of 9 DeFi tokens, 3 NFTs, Bitcoin, and Ethereum, we detect several bubbles overlapping the examined cryptoassets. We also uncover DeFi and NFT-specific bubbles in Summer 2020 suggesting distinct driving factors for this class of assets. We document that DeFi and NFTs bubbles are less recurrent but have higher magnitudes than cryptocurrencies' bubbles. We also find that COVID-19 and trading volume exacerbate bubble occurrences, while Total Value Locked (TVL) is negatively associated with cryptoassets' bubbles. Our results suggest that TVL can be used as a tool for market monitoring.
The development of Vehicular Ad Hoc Networks (VANET) has brought many advantages to facilitate the deployment of the Intelligent Transportation System (ITS). However, without proper protection, VANETs can be vulnerable to severe cyber-attacks. This paper explores the threats to the VANETs and proposes a security scheme for VANETs with a Blockchain (VNB). Furthermore, the proposed VNB with Ethereum was developed. With a graphical user interface, experiments were conducted. For ad hoc communications, a vehicle can randomly select another vehicle, and VNB will authenticate the selected vehicle with the Blockchain and Trusted Authority (TA). Preliminary test results successfully proved that Blockchain can be the key technology to mitigate the security threats to VANETs.
Blockchain technology has the characteristics of decentralization, traceability and tamper proof, which creates a reliable decentralized transaction mode, further accelerating the development of the blockchain platforms. However, with the popularization of various financial applications, security problems caused by blockchain digital assets, such as money laundering, illegal fundraising and phishing fraud, are constantly on the rise. Therefore, financial security has become an important issue in the blockchain ecosystem, and identifying the types of accounts in blockchain (e.g. miners, phishing accounts, Ponzi contracts, etc.) is of great significance in risk assessment and market supervision. In this paper, we construct an account interaction graph using raw blockchain data in a graph perspective, and proposes a joint learning framework for account identity inference on blockchain with graph contrast. We first capture transaction feature and correlation feature from interaction graph, and then perform sampling and data augmentation to generate multiple views for account subgraphs, finally jointly train the subgraph contrast and account classification task. Extensive experiments on Ethereum datasets show that our method achieves significant advantages in account identity inference task in terms of classification performance, scalability and generalization.
Manuel Valentin, Claus Pahl, Nabil El Ioini, Hamid R. Barzegar
Recent developments in distributed ledger technologies have created a whole new set of possibilities in the way of managing trust, security, privacy and traceability in computer-based transactions, principles which are increasingly gaining importance in the world of IoT. Currently, IoT devices are generally based on centralized, client-server systems, where digital service providers have complete control over user data and information generated by their devices. In this paper we present the development of a decentralized access and management system for IoT devices, where operations on these devices, such as the installation and management of apps are handled by a blockchain-based identification and record system. The system prototype consists of a smartphone application acting as a management hub for the whole system, an IoT device API implementation for allowing secure access to management and data functionalities, and a set of smart contracts on the Ethereum blockchain, where all necessary information for the functioning of the system is stored. The system allows app developers to provide their apps as Docker containers for IoT devices without the need to publish them on a centralized app store, and a regular user can subscribe to and access the available applications by paying in cryptocurrency without revealing any private information to the system. A cost and performance evaluation have been performed to assess the feasibility of the proposed solution.
Abstract Decentralized Finance (DeFi) is a system of financial products and services built and delivered through smart contracts on various blockchains. In recent years, DeFi has gained popularity and market capitalization. However, it has also been connected to crime, particularly various types of securities violations. The lack of Know Your Customer requirements in DeFi poses challenges for governments trying to mitigate potential offenses. This study aims to determine whether this problem is suited to a machine learning approach, namely, whether we can identify DeFi projects potentially engaging in securities violations based on their tokens’ smart contract code. We adapted prior works on detecting specific types of securities violations across Ethereum by building classifiers based on features extracted from DeFi projects’ tokens’ smart contract code (specifically, opcode-based features). Our final model was a random forest model that achieved an 80% F-1 score against a baseline of 50%. Notably, we further explored the code-based features that are the most important to our model’s performance in more detail by analyzing tokens’ Solidity code and conducting cosine similarity analyses. We found that one element of the code that our opcode-based features can capture is the implementation of the SafeMath library, although this does not account for the entirety of our features. Another contribution of our study is a new dataset, comprising (a) a verified ground truth dataset for tokens involved in securities violations and (b) a set of legitimate tokens from a reputable DeFi aggregator. This paper further discusses the potential use of a model like ours by prosecutors in enforcement efforts and connects it to a wider legal context.
In institutes of higher learning, most of the time course material development and delivery follow a centralized model which is fully lecturer-controlled. In this model, engaging students as partners in learning is a challenging problem as: 1) students are usually hesitant to contribute due to the fear of getting it wrong, 2) not much incentive for them to put in the extra effort, and 3) current online learning systems lack adequate facilities to support seamless and anonymous interactions between students. In this work, we propose EtherLearn, a blockchain based peer-learning system to distribute the control of how course material and formative assessments could be developed and delivered over the set of stakeholders in the particular course. EtherLearn leverages features of the rising blockchain technology, e.g., decentralization, anonymity, transparency and security to address the aforementioned concerns in university learning environments. To this end, we have successfully implemented a proof of concept for EtherLearn based on the Ethereum blockchain network. We have also conducted preliminary evaluations to demonstrate that it can be useful in decentralizing learning resource creation and student sharing in an encouraging teaching and learning environment.
Runkai Yang, Xiaolin Chang, Jelena Mišić, Vojislav B. Mišić
Bitcoin and Ethereum are the top two blockchain-based cryptocurrencies whether from cryptocurrency market cap or popularity. However, they are vulnerable to selfish mining and stubborn mining due to that both of them adopt Proof-of-Work consensus mechanism. In this paper, we develop a novel Markov model, which can study selfish mining and seven kinds of stubborn mining in both Bitcoin and Ethereum. The formulas are derived to calculate several key metrics, including relative revenue of miners, blockchain performance in terms of stale block ratio and transactions per second, and blockchain security in terms of resistance against double-spending attacks. Numerical analysis is conducted to investigate the quantitative relationship between the relative-revenue-optimal mining strategy for malicious miners and two miner features in Bitcoin and Ethereum, respectively. The quantitative analysis results can assist honest miners in detecting whether there is any malicious miner in the system and setting the threshold of mining node's hash power in order to prevent malicious miners from making profit through selfish and stubborn mining.
The multi-chain future is upon us. Modular architectures are coming to maturity across the ecosystem to scale bandwidth and throughput of cryptocurrency. One example of such is the Ethereum modular architecture, with its beacon chain, its execution chain, its Layer 2s, and soon its shards. These can all be thought as separate blockchains, heavily inter-connected with one another, and together forming an ecosystem. In this work, we call each of these interconnected blockchains "domains", and study the manifestation of Maximal Extractable Value (MEV, a generalization of "Miner Extractable Value") across them. In other words, we investigate whether there exists extractable value that depends on the ordering of transactions in two or more domains jointly. We first recall the definitions of Extractable and Maximal Extractable Value, before introducing a definition of Cross-Domain Maximal Extractable Value. We find that Cross-Domain MEV can be used to measure the incentive for transaction sequencers in different domains to collude with one another, and study the scenarios in which there exists such an incentive. We end the work with a list of negative externalities that might arise from cross-domain MEV extraction and lay out several open questions. We note that the formalism in this work is a work in progress, and we hope that it can serve as the basis for formal analysis tools in the style of those presented in Clockwork Finance, as well as for discussion on how to mitigate the upcoming negative externalities of substantial cross-domain MEV.
The multi-chain future is upon us. Modular architectures are coming to\nmaturity across the ecosystem to scale bandwidth and throughput of\ncryptocurrency. One example of such is the Ethereum modular architecture, with\nits beacon chain, its execution chain, its Layer 2s, and soon its shards. These\ncan all be thought as separate blockchains, heavily inter-connected with one\nanother, and together forming an ecosystem. In this work, we call each of these\ninterconnected blockchains "domains", and study the manifestation of Maximal\nExtractable Value (MEV, a generalization of "Miner Extractable Value") across\nthem. In other words, we investigate whether there exists extractable value\nthat depends on the ordering of transactions in two or more domains jointly. We\nfirst recall the definitions of Extractable and Maximal Extractable Value,\nbefore introducing a definition of Cross-Domain Maximal Extractable Value. We\nfind that Cross-Domain MEV can be used to measure the incentive for transaction\nsequencers in different domains to collude with one another, and study the\nscenarios in which there exists such an incentive. We end the work with a list\nof negative externalities that might arise from cross-domain MEV extraction and\nlay out several open questions. We note that the formalism in this work is a\nwork in progress, and we hope that it can serve as the basis for formal\nanalysis tools in the style of those presented in Clockwork Finance, as well as\nfor discussion on how to mitigate the upcoming negative externalities of\nsubstantial cross-domain MEV.\n
In recent years, blockchain technology has become a hot topic in various industries. With the development and maturity of blockchain technology, it has been applied to finance, law, etc., with its advantages of decentralization, openness, information security, and concealment. The application scenarios of industry are becoming more and more abundant. Compared with the traditional TPA payment contract form, the smart contract mechanism based on blockchain technology is obviously more efficient, convenient, and safe. Against this background, we design a smart payment contract suitable for cloud storage by studying Ethereum. The relationship clause in the smart payment contract should be regulated around the contract law. The smart contract payment linkage clause can be classified into three forms, including conditional effective type, contract joint type, and contract link type, which correspond to the contract law. Therefore, the contract legal system for smart contract payment linkage clauses should follow typified thinking. Based on blockchain technology, smart contracts not only reduce the number of interactions in contract execution but also allow users to stop paying for cloud services when data is lost or damaged. The precise method is to generate each node with a private chain and place the smart contract on the private chain. With the decentralization of the blockchain private chain, the advantages of read-only data, and traceability of information, the storage of smart payment contract data is more secure. Both parties to the transaction are more trustworthy. Therefore, the proposed system has a safe and efficient smart contract payment mechanism, which brings a good user experience to users, which proves the significance and value of this research.