【Abstract】This paper explores the dynamic connectedness between Defi assets and sector stock markets focused around the COVID-19 pandemic crisis. For that aim, this research applies the TVP-VAR model, and it also computes the optimal weights and hedge ratios for the Defi assets-sector equity portfolios using the DCC-GARCH model. Our main findings reveal that static connectedness is slightly economy-and sector-dependent. Regarding the dynamic connectedness, as expected, the total spillover index changes over time, showing a cruel impact of the global pandemic declaration. Net spillover indices show relevant differences between the Defi assets and certain sectors (net receivers) and sectors such as industrials, materials and information technology (time-varying net trans-mitters). Finally, the optimal hedge ratios reveal similar levels of coverage in all the periods analyzed, with slight upturns in the cost of such coverage in the crisis period caused by COVID-19.
【Abstract】The nonfungible token (NFT) marketplace spiked in the recent past. The concept originated initially as a token standard of Ethereum, an open-source blockchain with smart contract functionality, where each token is char-acterized by distinguishable signs. These types of tokens have unique digital properties that allow their distinct identification. NFTs, with their distinct qualities, can be fluidly traded with customized values according to their ages, rarity, and liquidity. The trading of NFTs has heavily influenced the growth of the decentralized application (dApp) marketplace, as exponential returns (thousand folds from their original value) on its ever-expanding market are being observed, leading to worldwide attention. However, the NFT ecosystem is in its nascence, and the associated technologies are still in their infancy. New researchers might be fascinated with the expo-nential, yet nebulous evolution of NFTs; however, this novelty has contributed to the paucity of systematic and conclusive published research work on this topic. This review portrays the NFT ecosystem multidimensionally, wherein the paper commences with an overview of state-of-the-art NFT technology and furnishes summary standards and desired properties. Finally, the study concludes with an elaborate discussion of the future outlook for and prime challenges faced by NFTs.
【Abstract】The term "Metaverse" first used in Neal Stephenson's sci-fi book Snow Crash in 1992, refers to a fusion of virtual and real existence. Nearly 30 years later, that definition is taking shape and promises to alter how people live and operate. This next evolution of Internet also known as Web3.0 will combine digital and physical elements. Multiple definitions can be found in the literature, with the most prevalent being the "new internet", among others such as "democratized virtual society", "persistent virtual spaces", "a digital twin of our own world for personalized value creation". Consequently, the common consensus dictates that Metaverse can be realized as a new form of the Internet, totally reshaped from what is already known. As we are heading towards the coexistence of Industry 5.0 and Society 5.0 (super smart and intelligent society), this paper attempts to present the definition of Metaverse, its evolution, the advantages and disadvantages, the pillars for the technological advancement which could be the fuel to spark future investigation and discussion as well as to accelerate the development of Metaverse towards the human centric and personalized society. Furthermore, in this manuscript, challenges and opportunities are presented (including Manufacturing), a brief comparison is performed versus Virtual Reality, and a conceptual framework for integrating Metaverse in Manufacturing is also presented.
【Abstract】This systematic literature review summarizes the extant research in the Behavioral Finance (BeFi) and digital asset spaces to understand better the interactions of behavioral effects on the pricing of assets constructed, enabled, and exchanged in Decentralized Finance (DeFi) markets. We find that asset pricing in these rapidly evolving markets is better explained through BeFi than through traditional finance (TradFi) theory. Investor attention, sentiment, heuristics and biases, and network effects interact to form a highly volatile and dynamic market. We offer a deterministic research framework with propositions for future research. We further provide investors with a theoretically and empirically supported structure to better inform their decisions through an understanding of BeFi applications to DeFi.
【Abstract】We present a measurement study on compositions of Decentralized Finance (DeFi) protocols, which aim to disrupt traditional finance and offer services on top of distributed ledgers, such as Ethereum. Understanding DeFi compositions is of great importance, as they may impact the development of ecosystem interoperability, are increasingly integrated with web technologies, and may introduce risks through complexity. Starting from a dataset of 23 labeled DeFi protocols and 10,663,881 associated Ethereum accounts, we study the interactions of protocols and associated smart contracts. From a network perspective, we find that decentralized exchange (DEX) and lending protocol account nodes have high degree and centrality values, that interactions among protocol nodes primarily occur in a strongly connected component, and that known community detection methods cannot disentangle DeFi protocols. Therefore, we propose an algorithm to decompose a protocol call into a nested set of building blocks that may be part of other DeFi protocols. This allows us to untangle and study protocol compositions. With a ground truth dataset that we have collected, we can demonstrate the algorithm's capability by finding that swaps are the most frequently used building blocks. As building blocks can be nested, that is, contained in each other, we provide visualizations of composition trees for deeper inspections. We also present a broad picture of DeFi compositions by extracting and flattening the entire nested building block structure across multiple DeFi protocols. Finally, to demonstrate the practicality of our approach, we present a case study that is inspired by the recent collapse of the UST stablecoin in the Terra ecosystem. Under the hypothetical assumption that the stablecoin USD Tether would experience a similar fate, we study which building blocks - and, thereby, DeFi protocols - would be affected. Overall, our results and methods contribute to a better understanding of a new family of financial products.
【Abstract】Tired of the power that mega platforms wield over the web, a growing chorus of internet users has hailed the arrival of blockchain technology, believing it can be used to build a new internet. Called "Web 3.0" by some, the new internet would allow users to exchange goods and services-digital currencies, cloud computing power, data storage-without needing a central intermediary to validate transactions. Instead, users would transact through decentralized platforms that use consensus-based mechanisms to verify users' exchanges. And rather than rely on fiat money, users would use the platforms' native currencies, called "utility tokens," as the media of exchange. Utility tokens also serve another purpose. Because rebuilding the internet is a costly endeavor, the groups developing decentralized platforms have turned toward selling utility tokens to fundraise their efforts. However, the issuance of utility tokens has caught the eye of the Securities and Exchange Commission ("SEC")-the federal agency in charge of enforcing the nation's securities laws-which has asserted its authority over utility token issuances. Unfortunately, the SEC's oversight lacks transparency, and the agency's rules do not protect investors against the risks they face in the digital economy. This Note calls for a bright-line test that would entitle issuers of utility tokens to a rebuttable presumption that the securities laws do not apply to sales of the issuers' utility tokens if their tokens meet each of the test's factors. This Note also advocates for modernizing the Regulation D private placement exemption so that it can address the realities implicit in token purchases. The changes pushed by this Note aim to quell developers' uncertainty and foster the ingenuity behind Web 3.0.
【Abstract】Bitcoin is a decentralized digital currency system that uses a distributed data structure called blockchain, a log that lists all transaction details accomplished with the currency. The bitcoin network delivers a promising infrastructure for one who makes use of e-currency in e-commerce. However, the transaction of bitcoin is highly suffered with some scalability issues that could not be overwhelmed with the prior methodologies. Hence, a novel scalability blockchain tumbling framework is proposed to tackle the scalability issues in which a rake interior blockchain etiquette is designed to increase the number of bitcoin transactions in which peer faction algorithm groups blocks that reduces propagation delay and ravenous algorithm ensure higher credibility of transaction with tamper resistant. However, transaction size of the record is high hence, to manage transaction record a novel batch payment into one transaction approach is utilized to limit the size of the transaction records by initiating a precise block using block summing-up and chagrin algorithms that collects all trust information about blocks. Thus the proposed framework attains 550 bitcoin transaction within 2 min and latency of proposed model is reduced below 60 s.
【Abstract】As the trendsetter of the digital currency market, Bitcoin fluctuates dramatically in a short period of time and has received increasing attention from investors. However, its high volatility has brought great uncertainty to the financial market. In this paper, we focus on forecasting the realized volatility of Bitcoin by using an optimized deep learning model. Firstly, we construct a more comprehensive system of factor indicators and employ different methods for feature selection, and find that the Random Forest-based feature selection fits better on the deep learning model. Then, we use the particle swarm optimization (PSO) algorithm to optimize the parameters of gated recurrent unit (GRU) model to improve the prediction accuracy, and the results show that the prediction accuracy of PSO-GRU model is 10.47%, 15.28%, 21.73%, 34.79% better than the GRU model, long-short term memory model, machine learning models and the generalized autoregressive conditional heteroscedasticity model on the mean absolute error, respectively. Finally, we establish an early risk warning scheme for Bitcoin volatility and a butterfly option arbitrage strategy, that provide investors with a reference for reasonable arrangement of trading strategies.
【Abstract】5G network slicing enables IoT networks to connect billions of heterogeneous objects providing high quality of service, high network capacity, and enhanced system throughput. It opens a new marketplace opportunity for cloud providers and network operators to sell portions of their networks to address specific customer needs in 5G applications. However, there are numerous open challenges to providing end-to-end slices due to complex business and engineering requirements from service and resource providers. To address these challenges, in this paper, we propose "Kaputa", a blockchain-enabled network slice broker and NFTenabled network slice marketplace. Here, different stakeholders such as cloud providers, network operators, RAN providers, and transport network providers can collaborate to rent their resources. Kaputa orchestrates the network slices with the help of blockchain smart contracts. The orchestrated network slices will be encoded as NFT tokens and published in the Kaputa NFT marketplace. Customers can purchase the network slices from the marketplace based on their 5G application requirements via paying crypto/fiat currency. The revenue will be distributed among different providers. The data provenance information of the network slices is encoded into Model Cards and stored in the blockchain ledger. A prototype of Kaputa has been implemented with FreedomFi and OpenAirInterface 5G core. To the best of our knowledge, this is the very first research that tries to represent 5G/6G network slices as NFTs. This design methodology provides enhanced transparency and auditability to the network slice orchestration process while providing an open platform to share and trade network slices in the marketplace.
