【Abstract】Prosumer companies exchanging utility surpluses in Eco-Industrial Parks (EIPs) is a promising alternative for industrial symbiosis to lower investment risks, take advantage of existing capacity and cut emissions. To incentivize participation in EIPs, a trustful mechanism is needed to negotiate and enforce terms of exchange. In this work, a peer-to-peer market of software agents representing different companies in automated negotiations of utility exchanges within an EIP is proposed. Agents will learn to strategically negotiate terms of exchanges while considering private preferences, necessities, and the public negotiation context of this market. Design details for the market comprising technological enablers such as Internet of Things, Blockchain, Smart Contracts and Decentralized Applications are presented. Moreover, the influence of learning context-dependent strategies on negotiation outcomes and market efficiency is analyzed. Results obtained are promising since social welfare and near equilibrium conditions emerge despite the selfish nature of participating companies and individual contextual perceptions of negotiation agents.
【Abstract】Purpose Despite blockchain's potential supply chain benefits, few organizations have moved beyond pilot projects. The paper aims to explore blockchain adoption intentions for supply chain applications using two theoretical perspectives: innovation diffusion theory (IDT) and institutional theory (IT). Design/methodology/approach Based on theory, five propositions were developed addressing the intention to adopt blockchain. The propositions were tested using scenario-based experiments with supply chain professionals. To provide additional insights, interviews with 21 supply chain professionals in 15 organizations representing 8 industries were content analyzed. Findings Experiments suggest that the intention to adopt blockchain is higher when there are government regulations regarding product origin, organizations are using updated cloud-based information systems and organizations are working with third-party consultants. The content analysis suggests that organizations that face normative pressures to adopt blockchain supply chain applications and recognize blockchain's relative advantage, compatibility and complexity are more likely to be actively seeking information about and adopting blockchain supply chain applications. The authors synthesize findings and provide new propositions to guide future research. Originality/value Using a multi-method approach, the study provides an important window into supply chain managers' perceptions of the necessary conditions to support organization-level blockchain adoption. The findings also indicate key characteristics present in supply chain networks poised for blockchain adoption.
【Abstract】In this study, an investigation is conducted into the phenomenon of price clustering in Bitcoin (BTC) denominated in the Japanese yen (JPY). It answers two questions using tick-by-tick data. The first is whether price clustering exists in BTC/JPY transactions, and the other is how the scale of price clustering varies throughout a trading day. With the assistance of statistical measures, the last two digits of BTC price were discovered to cluster at the numbers that end with '00'. In addition, the scales of BTC/JPY clustering at '00' tended to decline at the specific hour intervals. This study contributes to the emerging literature on price clustering and investor behavior.
【Abstract】We present a visual analytics tool, MiningVis, to explore the long-term historical evolution and dynamics of the Bitcoin mining ecosystem. Bitcoin is a cryptocurrency that attracts much attention but remains difficult to understand. Particularly important to the success, stability, and security of Bitcoin is a component of the system called mining. Miners are responsible for validating transactions and are incentivized to participate by the promise of a monetary reward. Mining pools have emerged as collectives of miners that ensure a more stable and predictable income. MiningVis aims to help analysts understand the evolution and dynamics of the Bitcoin mining ecosystem, including mining market statistics, multi-measure mining pool rankings, and pool hopping behavior. Each of these features can be compared to external data concerning pool characteristics and Bitcoin news. In order to assess the value of MiningVis, we conducted online interviews and insight-based user studies with Bitcoin miners. We describe research questions tackled and insights made by our participants and illustrate practical implications for visual analytics systems for Bitcoin mining.
【Abstract】Cyber-attacks are getting more sophisticated and nuanced. Intrusion Detection Systems (IDSs) are commonly used in a variety of networks to assist in the timely detection of intrusions. In recent years, blockchain technology has got a lot of attention as a way to share data without the need for a trusted third party. In particular, data recorded in a single block cannot be modified without impacting all subsequent blocks. For an effective update, an attacker will need to monitor the majority of network nodes, which is not feasible given the current network size. This work aims to create a deep learning-based IDS model with the potential of integrating blockchain technology with intrusion detection, inspired by the ability to apply blockchain in all fields. The proposed model outperforms the conventional systems with respect to accuracy in detecting the security attacks.
【Abstract】The security of financial apps on smartphones is threatened by a class of advanced and persistent malware that can bypass all existing security measures. Strong cryptography and trusted on-chip hardware modules are powerless against sophisticated attacks that supplant device owners through device input record/replay functionality, effectively hijacking their credentials, privileges, and actions. In this paper, we introduce Proof-of-Presence and Locality (PoPL), a new security measure that tackles this threat by leveraging sensors to prove the physical presence of device owners and therefore discriminate between malware-initiated transaction requests and legitimate ones. Moreover, PoPL neither imposes the expense of additional hardware nor compromises app usability. In order to demonstrate PoPL's practicality, we developed PoPLar, a challenge puzzle implementation of the PoPL concept that ensures usability even on limited screen sizes by the use of a dendrogram. We have made it available as an open-source library ready to be integrated with minimal effort with existing apps. We demonstrate PoPLar's effectiveness and ease of integration through case studies involving apps from the three top cryptocurrency exchanges and an open-source crypto wallet.
【Abstract】After its debut with Bitcoin in 2009, Blockchain has attracted enormous attention and been used in many different applications as a trusted black box. Many applications focus on exploiting the Blockchain-native features (e.g. trust from consensus, and smart contracts) while paying less attention to the application-specific requirements. In this paper, we initiate a systematic study on the applications in the education and training sector, where Blockchain is leveraged to combat diploma fraud. We first present a general system structure for digitized diploma management systems and identify both functional and non-functional requirements. We then show that all existing Blockchain-based systems fall short in meeting these requirements. Inspired by the analysis, we propose a Blockchain-facilitated solution by leveraging some basic cryptographic primitives and data structures. Our analysis shows that the proposed solution respects all the identified requirements by design and can be further extended to enhance its security and privacy guarantees. Finally, we investigate the proposed solution's computational complexity and demonstrate its practicality.
【Abstract】Digital phenomena pose unique challenges to social science researchers investigating the impact of new and changing technologies. In part, this challenge derives from the constantly evolving practices, actants, and geographies enrolled in the digital. When these phenomena are coupled with over-the-top expectations and media hype, initial impressions often mask the complicated and nuanced ways new technologies are put to use. Blockchain (and its original application Bitcoin) represent one of these new, unstable digital phenomena that simultaneously captures public imagination and generates powerful discourses of disruption and change. One way of clarifying the messiness of technologies like blockchain is to ground its practices within the materiality of geography. The DIGO framework proposed in this article uses four broad categories-discourses (measured via Twitter), infrastructures (indicated by Bitcoin mining), groupings (based on firms and exchanges), and outcomes (measured by initial coin offerings)-located in geographic space. Each category is meant to provide insight on blockchain as it unfolds across space and scale. The same framework can guide research on other digital phenomena, based on appropriate measures for each of the four DIGO foci.
【Abstract】We investigate short- and long-term effects of U.S. economic policy uncertainty (EPU) on bitcoin, gold, and the implied US stock market volatility (VIX). We apply an autoregressive distributed lag model (ARDL) to monthly data. Our results suggest EPU significantly negatively (positively) impacts bitcoin over short (long) horizons. In contrast to the extant literature we find the magnitude of the effect of EPU on bitcoin returns weakens over longer horizons. Our empirical results provide a cautionary note for holders of asset portfolios that include bitcoin in their mix as a hedge against uncertainty.
【Abstract】The conditional anonymous scheme for permissionless blockchains satisfies anonymity and traceability simultaneously. Specifically, though transactions are published anonymously, the supervision authority can still trace the identity of the transaction producer when there is a suspicious transaction. However, the uncontrolled randomness employed in existing schemes leads to security risks and unsatisfying storage efficiency. In order to deal with these problems, we propose a secure and efficient conditional anonymous scheme in permissionless blockchains in this paper. In particular, we employ the bilinear ring signature to avoid security risks such as secret key leakage, covert communication and hidden persistent storage. Subsequently, the double-chain structure is introduced to significantly improve the storage efficiency, in which a supervision chain storing users' hidden identity information is built on top of permissionless blockchains. We demonstrate the security and efficiency of our conditional anonymous scheme by numerous analyses and experiments.
【Abstract】Blockchain is an emerging technology, with a decentralized infrastructure avoiding third party dependency. Smartcontracts are one of the features of Ethereum blockchain, capable of running distributed applications in unreliableenvironments, enabling process automation and being one of the most sought technologies due to the highcustomization added to transactions. However, little is known about predicting the cost and execution time behavior of blockchain-based system transactions. This work aims to evaluate the performance of an Ethereum network through an application designed to analyze the cost and time of transactions that store characters in the blockchain. To meet the proposed objective, we designed an application for performing transactions with data inclusion and query on a blockchain, collecting time and cost data. As main conclusions of this work we have: the Ethereum platform proved to be inconstant in relation to the processing time of transactions on the blockchain and the application developed based on blockchain can provide a mechanism to evaluate text-type operations on Ethereum network.
【Abstract】Cloud Infrastructure as a Service (IaaS) Service Level Agreements (SLAs) assessment constitutes the de facto area of interest and applications in the public cloud infrastructure. However, the domination of colossal corporations tends to monopolize the way metrics and Key Performance Indicators (KPIs) are measured and determined, leading to governed environments where the clientele is unable to obtain accurate and unbiased assessment of SLAs. Leaning toward SLA self-assessment, this paper provides a fair SLA consensus approach with innate transparency and privacy by leveraging permissioned blockchains that are equipped with Trusted Execution Environments (TEEs). The SLA assessment intelligence is performed inside enclaved smart contracts isolated from the on-chain entities views. The result constitutes a permissioned blockchain ecosystem where the IaaS and their clientele commonly agree on all the respective SLA monitoring and computation rules beforehand, as defined in any SLA assessment process, while the SLA consensus scheme constantly audits the SLA metrics based on these pre-approved regulations.
【Abstract】Background: As a medium of exchange, money enables the transfer of economic value and forms the basis of financial transactions. The transition from the third to the fourth industrial revolution has brought about technologies such as blockchain and cryptocurrencies that are transforming monetary transactions and methods of payments. Objectives: This article discusses an exploratory qualitative study into the use of the blockchain technology to facilitate the processes and payments related to land and landed property administration. Method: Nineteen semi-structured face-to-face interviews were conducted with role-players who are involved in an authoritative capacity in the current property transfer process. Findings: The findings show that blockchain technologies could significantly improve the processes involved in maintaining the electronic records associated with landed property. Blockchain technology has only been associated with cryptocurrencies before, and the argument advanced is that fiat currency should be able to be used with the same technology. To maintain the integrity of the property register, the deeds office and the South African Reserve Bank (SARB) must remain in control of the processes. Irrevocable payments should be made against registration confirmation, thus replacing the current paper-based processes with electronic records. Conclusion: Blockchain technologies can be used with fiat currency and should be considered for ownership tracking of immovable property.
【Abstract】Nowadays, business enactments almost exclusively focus on human-to-human business transactions. However, the ubiquitousness of smart devices enables business enactments among autonomously acting machines, thereby providing the foundation for the machine-driven Machine-to-Everything (M2X) Economy. Human-to-human business is governed by enforceable contracts either in the form of oral, or written agreements. Still, a machine-driven ecosystem requires a digital equivalent that is accessible to all stakeholders. Additionally, an electronic contract platform enables fact-tracking, non-repudiation, auditability and tamper-resistant storage of information in a distributed multi-stakeholder setting. A suitable approach for M2X enactments are electronic smart contracts that allow to govern business transactions using a computerized transaction protocol such as a blockchain. In this position paper, we argue in favor of an open, decentralized and distributed smart contract-based M2X Economy that supports the corresponding multi-stakeholder ecosystem and facilitates M2X value exchange, collaborations, and business enactments. Finally, it allows for a distributed e-governance model that fosters open platforms and interoperability. Thus, serving as a foundation for the ubiquitous M2X Economy and its ecosystem.
