【Abstract】As a concern with manufacturing industries, circular economy (CE) practices-often labeled "circular manufacturing (CM)"-are industrial tasks through which several circular economy principles have been integrated. Among these circular manufacturing strategies, "3R" (recycle, refurbish/remanufacture, and reuse/redistribute) is the key strategy that assists the manufacturing industry with closing the loop for sustainability. An effective inclusion and management of 3R lead a firm to a greater likelihood of successfully integrating CE and CM. In recent years, remanufacturing has gained greater prominence, especially with the emergence of technology, including cyber-physical systems. These technologies assist the remanufacturing firm with efficient take-back systems through tracking. However, data transferred through these technologies among value chain partners in remanufacturing are not reliable. Due to the lack of trust and transparency, value chain partners are hesitant to participate in remanufacturing supply chains. To address the limitation of technologies in remanufacturing, blockchain has been introduced to secure the data. Despite the advantages of blockchain technology, practitioners face difficulties in integrating these blockchain technologies into the remanufacturing context. Several earlier studies addressed the challenges of implementing blockchain, but no earlier studies have specifically examined remanufacturing industries, which are entirely different from forward supply chain industries. Concerning the fact, this study identifies the barriers that exist with the implementation of blockchain technology in the application of the remanufacturing sector. A framework has been proposed and validated in a Danish automotive parts remanufacturing company. Multi-criteria decision-making method has been used to identify the effective and most influential barriers among common barriers. Results reveal that "scaling of technology" (B6) is the key barrier of BCT implementation in remanufacturing context. This study concludes with useful discussions based on the results along with the recommendations to eradicate those influential barriers and their respective impacts on SDGs (SDG4, SDG8, SDG9, and SDG17). Finally, this study sheds light on future enhancements on the integration of blockchain technology in remanufacturing to reap several benefits of circular manufacturing.
【Abstract】The advantages of blockchain virtual currency are convenient circulation, low transaction costs, and decentralized power. At present, more and more investors have focused their investment in the blockchain virtual currency. Transaction data of blockchain virtual currency belongs to the financial time series, which is noisy and random, bringing challenges to the prediction of transaction trends. The improved deep belief network (IDBN) model and Echo state network (ESN) are constructed based on deep belief network (DBN) model to explore the long short-term memory (LSTM) model and the transaction prediction of blockchain virtual currency under the DBN and to improve the transaction prediction accuracy of the blockchain virtual currency. In addition, the parameters of IDBN model were optimized using particle swarm optimization (PSO) algorithm, which are verified with the transaction data of stocks and blockchain virtual currencies (Bitcoin, Bitcoin Cash, and Ethereum), and compared with other cash algorithms for analysis. The results show that the PSO-IDBN-based time series prediction model proposed in this study can be applied to predicting the high-latitude and high -complexity data, showing superior performance compared to the traditional time series prediction and other deep learning prediction methods. @2021 Elsevier B.V. All rights reserved.
【Abstract】This paper studies the strategy of adopting blockchain technology (BT) in two supply chains, each consisting of one manufacturer and one retailer. We find that the adoption of BT in supply chains is related to consumers' traceability awareness and the blockchain-based traceability cost-sharing between the manufacturer and retailer. Specifically, when both consumers' traceability awareness and the proportion of the blockchain-based traceability cost borne by each retailer are low or moderate, the equilibrium strategy could be that one or both supply chains adopt BT. Moreover, when one supply chain adopts BT, the other may be a free rider. When both supply chains adopt BT, one supply chain can gain a competitive advantage when its retailer shares more of the blockchain-based traceability cost than the rival. Counterintuitively, when traceability awareness is high, neither of the two supply chains should adopt BT.
【Abstract】Purpose This paper aims to introduce, conceptualize and demonstrate a software tool named "Blockchain-Enabled Beer Game" (BEBG) for familiarizing the application of blockchain in inventory management, one of the critical components of supply chain management. Design/methodology/approach This paper follows a methodology of design-based research and develops a software tool in the form of a role-play simulation game. The proposed game adopts the theme of the traditional beer distribution game to establish a blockchain-enabled scenario for inventory management. A decentralized application (DApp) was prototyped on the Ethereum blockchain to demonstrate the tool. Findings The proposed software tool is effective in teaching and training the application of blockchain in inventory management. While interacting with BEBG, players witness how each inventory-related transaction gets secured with blockchain. A basic understanding of the fundamentals of blockchain is a prerequisite for using this tool. BEBG is not self-explanatory, and an instructor is essential for assisting the players. Originality/value Software tools currently available to familiarize with blockchain technology cannot convey its practical applications. Addressing this gap, BEBG allows the users to experience the application of blockchain in inventory management. Academic institutions, especially business schools, can use this tool to teach the students the practical use of blockchain technology. Industries can adopt BEBG for training the employees. The research community can devise BEBG to infer the impact of blockchain in supply chain management.
【Abstract】The emergence of blockchains has fueled the development of resilient systems that can deal with Byzantine failures due to crashes, bugs, or even malicious behavior. Recently, we have also seen the exploration of sharding in these resilient systems, this to provide the scalability required by very large data-based applications. Unfortunately, current sharded resilient systems all use system-specific specialized approaches toward sharding that do not provide the flexibility of traditional sharded data management systems. To improve on this situation, we fundamentally look at the design of sharded resilient systems. We do so by introducing ByShard, a unifying framework for the study of sharded resilient systems. Within this framework, we show how two-phase commit and two-phase locking-two techniques central to providing atomicity and isolation in traditional sharded databases-can be implemented efficiently in a Byzantine environment, this with a minimal usage of costly Byzantine resilient primitives. Based on these techniques, we propose eighteen multi-shard transaction processing protocols. Finally, we practically evaluate these protocols and show that each protocol supports high transaction throughput and provides scalability while each striking its own trade-off between throughput, isolation level, latency, and abort rate. As such, our work provides a strong foundation for the development of ACID-compliant general-purpose and flexible sharded resilient data management systems.
【Abstract】Blockchain technology has emerged as the cornerstone of many decentralized applications operating among otherwise untrusted peers. However, it is well known that existing blockchain systems do not scale well. Transactions are often executed and committed sequentially in order to maintain the same view of the total order. Furthermore, it is necessary to duplicate both transaction data and their executions in every node in the blockchain network for integrity assurance. Such storage and computation requirements put significant burdens on the blockchain system, not only limiting system scalability but also undermining system security and robustness by making the network more centralized. To tackle these problems, in this paper, we propose SlimChain, a novel blockchain system that scales transactions through off-chain storage and parallel processing. Advocating a stateless design, SlimChain maintains only the short commitments of ledger states on-chain while dedicating transaction executions and data storage to off-chain nodes. To realize SlimChain, we propose new schemes for off-chain smart contract execution, on-chain transaction validation, and state commitment. We also propose optimizations to reduce network transmissions and a new sharding technique to improve system scalability further. Extensive experiments are conducted to validate the performance of the proposed SlimChain system. Compared with the existing systems, SlimChain reduces the on-chain storage requirements by 97% similar to 99%, while also improving the peak throughput by 1.4X similar to 15.6X.
【Abstract】Decentralized autonomous organizations (DAO) launched on a blockchain and governed by a smart contract promises to bring self-organization to a new technological level. Crisis management has no standard decentralized solution within DAO yet. A central authority is a natural component due to compliance reasons in certain domains, for example, special-purpose financing, in which the DAO governance model could be reasonably applied. More generally, a centralized DAO representative could streamline implementing DAO decisions that involve interactions with legacy systems. The article presents a perspective of modern technologies for organizing a foundation for special-purpose financing and considers longevity as a model example of the purpose.
【Abstract】Uniswap, as with other DEXs, has gained much attention this year because it is a non-custodial and publicly verifiable exchange that allows users to trade digital assets without trusted third parties. However, its simplicity and lack of regulation also make it easy to execute initial coin offering scams by listing non-valuable tokens. This method of performing scams is known as rug pull, a phenomenon that already exists in traditional finance but has become more relevant in DeFi. Various projects have contributed to detecting rug pulls in EVM compatible chains. However, the first longitudinal and academic step to detecting and characterizing scam tokens on Uniswap was made. The authors collected all the transactions related to the Uniswap V2 exchange and proposed a machine learning algorithm to label tokens as scams. However, the algorithm is only valuable for detecting scams accurately after they have been executed. This paper increases their dataset by 20K tokens and proposes a new methodology to label tokens as scams. After manually analyzing the data, we devised a theoretical classification of different malicious maneuvers in the Uniswap protocol. We propose various machine-learning-based algorithms with new, relevant features related to the token propagation and smart contract heuristics to detect potential rug pulls before they occur. In general, the models proposed achieved similar results. The best model obtained accuracy of 0.9936, recall of 0.9540, and precision of 0.9838 in distinguishing non-malicious tokens from scams prior to the malicious maneuver.
【Abstract】Digital organizations form part of the new wave of blockchain technologies, following Bitcoin and related cryptocurrencies. "Utopia of Abstraction" offers an analysis of the utopian promise of digital organizations through a reading of one such project, Colony. We provide a critique of the ideology of Colony's white paper, supplemented by readings of pages from its website, as a member of a genre of texts that promote their products through seemingly neutral, technical descriptions. Colony's texts suggest an abstract, contextless and scaleless organizational solution-powered by smart contracts on a blockchain-that, according to its proponents, might be applied to any social situation, from small firm to state-level governance. For its users, this organization combines a promise of sovereignty removed from that of the state, as well as implied financial returns. Our reading of Colony echoes the critiques of scholars arguing that cyberlibertarianism is a dominant politic of blockchain technologies. Furthermore, drawing on critiques of code as law and the elision of the social in smart contracts, we argue that Colony's vision presents a model of technical organization that substitutes for the state in the context of waning popular sovereignty. We ultimately suggest an understanding of digital organizations reminiscent of the settler colonial situation: the assumption of an empty social space to be filled, and the promise of sovereignty and riches for those occupying it. Analysis of these logics is relevant as hype increases around non-fungible tokens, Web3, and the corporate metaverse as well as data practices more widely.
