The Internet pervades many aspects of modern life offering up seemingly boundless opportunities to connect, inform and be informed. As the range and number of sources for information online explode, how people go about selecting and interpreting information has become a pertinent area for study, not least in the recent light of the prevalence of fake-news—as people are well known to act upon information they believe to be trustworthy. Where the decision to act incurs risk, an inability to accurately select and assess the credibility of information presents a challenge. <br/><br/>This extended abstract summarizes findings from a study of 57 Bitcoin users. Our analysis shows that this self-identifying technical and expert community was not significantly influenced by confirmation bias (a facet of fake-news). However, the same users also failed to demonstrate a true reliance upon the facts contained in news articles, often deferring trust to the source of the news which could still render them susceptible to fake-news, and, in turn, place their speculation of the crypto-currency at risk.
Crowdsourcing relies on people's contributions to meet product- or system-level objectives. Crowdsourcing-based methods have been implemented in various cyber-physical systems and realtime markets. This paper explores a framework for Crowdsourced Energy Systems (CES), where small-scale energy generation or energy trading is crowdsourced from distributed energy resources, electric vehicles, and shapable loads. The merits/pillars of energy crowdsourcing are discussed. Then, an operational model for CESs in distribution networks with different types of crowdsourcees is proposed. The model yields a market equilibrium depicting traditional and distributed generator and load setpoints. Given these setpoints, crowdsourcing incentives are designed to steer crowdsourcees to the equilibrium. As the number of crowdsourcees and energy trading transactions scales up, a secure energy trading platform is required. To that end, the presented framework is integrated with a lightweight Blockchain implementation and smart contracts. Numerical tests are provided to showcase the overall implementation.
This research work aims to study the intrinsic characteristics of the most \nrepresentative virtual currency among all the existing cryptocurrencies in the market, \nBitcoin, considering it under two points of view: as a means of payment in the \nexchange of goods and services and as a financial or investment asset for \nspeculative purposes in the short and medium term. \nLikewise, reference will be made to the different regulatory flows in terms of their \nlegal nature and, in particular, to the tax treatment in the European Union, the United \nStates and other selected jurisdictions. \nThe ultimate goal of this research is to analyze the current deficiencies of the global \nlegal status of Bitcoin in order to carry out the corresponding recommendations that \nallow an approximation to the global control of taxation and consumer protection.
Se tratan algunas cuestiones clave que, desde la óptica legal, y en particular del derecho de la contratación, comienza a plantear en España la introducción y generalización en la práctica de sistemas de contratación electrónica fundados en la tecnología denominada de cadenas de bloques o registros distribuidos, y en el empleo de los llamados contratos inteligentes.
Smart contracts can automatically perform the contract terms according to the received information, and it is one of the most important research fields in digital society. The core of smart contracts is algorithm contract, that is, the parties reach an agreement on the contents of the contract and perform the contracts according to the behaviors written in certain computer algorithms. It not only needs to make sure about the correctness of smart contracts code, but also should provide a credible contract code execution environment. Blockchain provides a trusted execution and storage environment for smart contracts by the distributed secure storage, consistency verification and encryption technology. Current challenge is how to assure that smart contract can be executed as the parties' willingness. This paper introduces formal modeling and verification in formal methods to make smart contract model and verify the properties of smart contracts. Formal methods combined with smart contracts aim to reduce the potential errors and cost during contract development process. The description of a general and formal smart contract template is provided. The tool of model checking, SPIN, is used to verify the correctness and necessary properties for a smart contract template. The research shows model checking will be useful and necessary for smart contracts.
Deepak Puthal, Nisha Malik, Saraju P. Mohanty, Elias Kougianos · 5 authors
The blockchain is emerging as one of the most propitious and ingenious technologies of cybersecurity. In its germinal state, the technology has successfully replaced economic transaction systems in various organizations and has the potential to revamp heterogeneous business models in different industries. Although it promises a secure distributed framework to facilitate sharing, exchanging, and the integration of information across all users and third parties, it is important for the planners and decision makers to analyze it in depth for its suitability in their industry and business applications. The blockchain should be deployed only if it is applicable and provides security with better opportunities for obtaining increased revenue and reductions in cost. This article presents an overview of this technology for the realization of security across distributed parties in an impregnable and transparent way.
Abstract This paper outlines how the digital currency and network technology of bitcoin functions and explores the context from which it emerged. Bitcoin was conceived in 2008 as an attempt to alleviate trust in government and banks which was at a low during this period of financial crisis. However, with bitcoin trust does not dissipate, rather it shifts. Trust moves from trust in banks or states to trust in algorithms and encryption software. There is a move from conventional trust in the gold standard—“In Gold We Trust”—to the trust announced on U.S. currency—“In God We Trust”—to trust in software and networks—“In Digital We Trust”. The hyperbole of bitcoin discourse is deemed to be an expression of the Californian Ideology, which itself often conceals a right-wing agenda. The paper analyses the hype behind the celebration of decentralised digital networks. It proposes that a form of network fetishism operates here. The failure of bitcoin as a currency (rather than as a hoarded commodity in an emergent bubble) and as an idea might be attributed to the failure to see how ultra-modern digital networks conceal very traditional consolidation of power and capital. The rise and fall of bitcoin, in terms of its original ambition, serves as a cautionary tale in the digital age—it reveals how ingenious innovations that might challenge power and the consolidation of capital become co-opted and colonised by capital. Finally, the paper offers a discussion of the possible progressive uses of the digital technology bitcoin has facilitated.
Tin Leelavimolsilp, Long Tran-Thanh, Sebastian Stein
Eyal and Sirer's selfish mining strategy has demonstrated that Bitcoin system is not secure even if 50% of total mining power is held by altruistic miners. Since then, researchers have been investigating either to improve the efficiency of selfish mining, or how to defend against it, typically in a single selfish miner setting. Yet there is no research on a selfish mining strategies concurrently used by multiple miners in the system. The effectiveness of such selfish mining strategies and their required mining power under such multiple selfish miners setting remains unknown. In this paper, a preliminary investigation and our findings of selfish mining strategy used by multiple miners are reported. In addition, the conventional model of Bitcoin system is slightly redesigned to tackle its shortcoming: namely, a concurrency of individual mining processes. Although a theoretical analysis of selfish mining strategy under this setting is yet to be established, the current findings based on simulations is promising and of great interest. In particular, our work shows that a lower bound of power threshold required for selfish mining strategy decreases in proportion to a number of selfish miners. Moreover, there exist Nash equilibria where all selfish miners in the system do not change to an honest mining strategy and simultaneously earn their unfair amount of mining reward given that they equally possess sufficiently large mining power. Lastly, our new model yields a power threshold for mounting selfish mining strategy slightly greater than one from the conventional model.
Danielle Mendes Thame Denny, Roberto Ferreira Paulo, Douglas de Castro
O presente artigo tem o objetivo de analisar a Agenda 2030 frente à possibilidade do uso de plataformas digitais para implementar políticas públicas, integrando indivíduos, empresas e governos. Primeiro discorre sobre as características da Agenda 2030, na sequência identifica as iniciativas já aplicadas de uso de tecnologia para implementar a governança socioambiental, para então apontar as falhas técnicas com relação aos mecanismos de monitoramento atual e apresentar as vantagens que o uso da tecnologia de contabilidade distribuída poderia trazer. A conclusão principal do trabalho é que o monitoramento é fundamental para a efetividade das ferramentas de governança global que visem implementar os Objetivos do Desenvolvimento Sustentável da Agenda 2030 e que o uso do blockchain tem muito a contribuir para coordenar interesses antagônicos na busca de metas comuns, quantificáveis e verificáveis. A metodologia escolhida foi a análise qualitativa com pesquisa documental, legislativa e bibliográfica.
O objetivo do artigo consiste em responder ao seguinte problema de pesquisa: a falta de regulamentação específica para as criptomoedas possui relação com a expansão das modalidades criminosas? Para responder ao referido problema, é necessário abordar o conceito de criptomoedas, sua expansão, o papel das instituições de controle e os limites jurídicos que reconhecem a existência dessa nova modalidade de tecnologia. Partimos do suposto de que o advento das criptomoedas em si não consiste em uma atividade criminosa pela ausência de regulamentação pelo Banco Central, mas sim, pode vir a se encaixar em tipos penais pelo mau uso dos softwares. A abordagem é qualitativa, com suporte em revisão de literatura e análise descritiva dos fenômenos pesquisados, além da consulta sobre a legislação sobre o tema. A contribuição é relevante pelo ineditismo e pela importância do tema no contexto financeiro e jurídico das transações realizadas em modalidade virtual. Conclui-se que não é possível associar diretamente o uso de bitcoins com a expansão das modalidades criminosas, entretanto, resta evidente que há relação subjacente entre a falta de regulamentação e a especialização de práticas criminosas que usam o ciberespaço como ambiente.
Rodrigo Valente Giublin Teixeira, Felipe Rangel da Silva
Pelo presente se busca analisar o fenômeno da moeda eletrônica Bitcoin e o impacto jurídico por esta causado, especialmente no que cerne ao confronto aparente com a soberania estatal, uma vez que dada sua internacionalidade e a dificuldade ou impossibilidade de proibição do uso, poder-se-ia em um primeiro momento vislumbrar ofensa ao instituto jurídico, o que será desmistificado. Para tanto, utilizou-se de pesquisa bibliográfica, especialmente estrangeira, dado o ainda ineditismo do tema, com autores de áreas distintas da ciência jurídica, pois assim exigido para análise das questões técnicas de funcionamento da ferramenta e também para delimitação do impacto financeiro causado pela nova moeda, emprestando conceitos e institutos da ciência econômica para aplicação. Contudo, apesar de necessário, o aprofundamento interdisciplinar se restringe ao suficiente para possibilitar a análise jurídica, a qual se dá, por sua vez, em âmbito de Direito Público, não se tendo conhecimento de análise anterior realizada sob o mesmo prisma.
The Law 5/2010 of Local Autonomy of Andalusia deepens in the capacities of the municipalities to decide on themselves: the procedures of segregation of municipal terms need express conformity of the absolute majority of the plenary session of the local government of the municipality that suffers the segregation. On the other hand, the municipalities have the possibility of spatially organizing their municipal area, or part of it, in territorial districts as a manifestation of their full political autonomy, and may be of a deconcentrated nature (hamlets, parishes, villages, neighborhoods, churches, councils, districts, adjoining and other analogous places) or decentralized (Autonomous Local Entities or Neighborhood Entities). As for the Autonomous Local Entities conformed in Andalusia, they are usually a previous step to the creation of a new municipality, for which the Law 27/2013, of Rationalization and Sustainability of the Local Administration has established a population limit that, in the practice, suppresses segregationist aspirations.
The nation of Bosnia and Herzegovina (BiH), on southeastern Europe’s Balkan Peninsula, is a unique product of international peace building based on a consociational model of ethnic power sharing. Organized around protection of “vital interests” of its constituent ethnic communities, the BiH state is radically decentralized. In forest administration, national government is practically nonexistent; multiple substate entities including cantons and municipalities operate as autonomous, self-governing units. This paper finds that the politics of accommodation, ironically couched in the language of rights, creates conditions of illiberal dissociation which block consensual natural resource governance. Conservation policies which require political compromise, thus, face a challenge in BiH’s illiberal consociation. Through policy analysis and interviews with representatives of key organizations affected by the 2008 Law on Una National Park, this study finds that when policies are implemented at levels of expected cooperation, the resultant needs are to reconcile rifts of interpretation and coordinate competencies vertically among dissociative bureaucracies.
Feb 6, 2018·Caginalp, C., & Caginalp, G. (2018). Opinion: Valuation, liquidity price, and stability of cryptocurrencies. Proceedings of the National Academy of Sciences, 115(6), 1131-1134
Cryptocurrencies are examined through the asset flow equations and experimental asset markets. Since tangible value of a typical cryptocurrency is non-existent, the theory suggests that price will gravitate toward liquidity value, i.e., the total amount of cash available for purchase of the asset divided by the number of units. Thus it is unlikely that cryptocurrencies in their current form will be stable in the absence of a mechanism of a link to value.
Cross-institutional healthcare predictive modeling can accelerate research and facilitate quality improvement initiatives, and thus is important for national healthcare delivery priorities. For example, a model that predicts risk of re-admission for a particular set of patients will be more generalizable if developed with data from multiple institutions. While privacy-protecting methods to build predictive models exist, most are based on a centralized architecture, which presents security and robustness vulnerabilities such as single-point-of-failure (and single-point-of-breach) and accidental or malicious modification of records. In this article, we describe a new framework, ModelChain, to adapt Blockchain technology for privacy-preserving machine learning. Each participating site contributes to model parameter estimation without revealing any patient health information (i.e., only model data, no observation-level data, are exchanged across institutions). We integrate privacy-preserving online machine learning with a private Blockchain network, apply transaction metadata to disseminate partial models, and design a new proof-of-information algorithm to determine the order of the online learning process. We also discuss the benefits and potential issues of applying Blockchain technology to solve the privacy-preserving healthcare predictive modeling task and to increase interoperability between institutions, to support the Nationwide Interoperability Roadmap and national healthcare delivery priorities such as Patient-Centered Outcomes Research (PCOR).
La cryptographie et la puissance des réseaux ont rendu possible l’existence de monnaies purement numériques et dépourvues d’une autorité centrale de contrôle.
Fiber-reinforced soft actuators use inextensible fibers to shape the expansion of elastomeric fluid-filled chambers. The classic example, McKibben muscles, is part of a broader class of cylindrical soft actuators known as fiber-reinforced elastomeric enclosures (FREEs). These actuators can be designed to twist while extending or contracting. Using a circuit of conductive, electrically insulated wire as the reinforcing fibers allows one to measure the motion of the actuator with the circuit inductance. These sensors, developed previously for McKibben muscles, are known as “Smart Braids.” This paper extends the concept of Smart Braids to the broader class of two-fiber-family cylindrical FREEs. A dimensionless model for the inductance of Smart Braid FREEs is presented that can be scaled to specific sensor geometries. This model depends only on the ratio of the fiber lengths in the two families and the angle of one of the fibers. The model was validated both numerically and experimentally, predicting the sensitivity of experimental sensors accurately, the largest errors being -11% and 9%. The model presented in this paper will enable high-level design decisions for Smart Braid FREES and optimization without computationally expensive direct numerical simulation.
The financial sector in China is well known as a government-dominated hierarchy, and the access to financial services has been controlled primarily by the state-run banks. Fin-tech businesses, or so-called “Internet finance,” in China have included new actors such as Internet companies, small and medium enterprises, and small lay investors in the financial regime. The new entrants’ technology-mediated interactions with the government engendered new politico-economic relations within and beyond the market, in the cyberspace and in everyday life. How have the Chinese modes of financial inclusion reconfigured the power relations between the state, corporations, and the investing public in China? Through the political-economic analyses of three specific forms of fin-tech businesses—third-party payment, peer-to-peer lending, and money market fund this article argues that Chinese fin-techs have enabled a broader societal participation to investment practices and empowered Internet corporations alongside the state-controlled financial systems. Thus, such an inclusion is less about the “inclusive finance” endorsed by the World Bank for the under-represented social groups’ accesses to financial services. It is more of a technology-facilitated financialization initiated by the state, promoted by information technology companies, and popularized among small investors. Rather than leading to the decentralization of financial power, China’s fin-tech has formed a higher level of concentration of financial capital controlled by the Chinese oligopoly Internet corporations. Moreover, the collaborations and competitions between the growing fin-tech companies and the state-owned financial sector deserve further observations.
Existing Byzantine fault tolerance (BFT) protocols face significant challenges in the consortium blockchain scenario. On the one hand, we can make little assumptions about the reliability and security of the underlying Internet. On the other hand, the applications on consortium blockchains demand a system as scalable as the Bit-coin but providing much higher performance, as well as provable safety. We present a new BFT protocol, Gosig, that combines crypto-based secret leader selection and multi-round voting in the protocol layer with implementation layer optimizations such as gossip-based message propagation. In particular, Gosig guarantees safety even in a network fully controlled by adversaries, while providing provable liveness with easy-to-achieve network connectivity assumption. On a wide area testbed consisting of 140 Amazon EC2 servers spanning 14 cities on five continents, we show that Gosig can achieve over 4,000 transactions per second with less than 1 minute transaction confirmation time.
Roberto Tonelli, G. A. Pierro, Marco Ortu, Giuseppe Destefanis
Smart contracts (SC) are software programs that reside and run over a blockchain. The code can be written in different languages with the common purpose of implementing various kinds of transactions onto the hosting blockchain. They are ruled by the blockchain infrastructure with the intent to automatically implement the typical conditions of traditional contracts. Programs must satisfy context-dependent constraints which are quite different from traditional software code. In particular, since the bytecode is uploaded in the hosting blockchain, the size, computational resources, interaction between different parts of the program are all limited. This is true even if the specific programming languages implement more or less the same constructs as that of traditional languages: there is not the same freedom as in normal software development. The working hypothesis used in this article is that Smart Contract specific constraints should be captured by specific software metrics (that may differ from traditional software metrics). We tested this hypothesis on 85K Smart Contracts written in Solidity and uploaded on the Ethereum blockchain. We analyzed Smart Contracts from two repositories "Etherscan" and "Smart Corpus" and we computed the statistics of a set of software metrics related to Smart Contracts and compared them to the metrics extracted from more traditional software projects. Our results show that generally, Smart Contract metrics have more restricted ranges than the corresponding metrics in traditional software systems. Some of the stylized facts, like power law in the tail of the distribution of some metrics, are only approximate but the lines of code follow a log-normal distribution which reminds us of the same behaviour already found in traditional software systems.
This paper is inspired by the project proposal ID 7807232014 submitted for the EU Horizon 2020 topic ICT-11-2017 in April 25, 2017. It aims at applying state-of-the-art ICT technologies, systems and functions such as Cloud/Fog and IoT to enable food supply chain. A new approach will lead to trusted cooperative applications and services within the agro-food chains. Blockchain technologies will enhance the transparency, information flow and management capacity allowing better interactions of farmers with other part of supply chain, especially the consumer. Our research will provide better performing value chains by proposing new food-on-demand business model, based on new Quality of Experience (QoE) food metrics, bridging the gap between subjective experience and objective matrics based on quality standards. Finally, we provided an awareness qustionaire for fresh food products (FFP) and survay for a group of 30 students from the University of Skopje. This study showed that the majority of students are aware and focused just on few common FFP aspects without deeper knowledge of FFP quality.
Fiscal decentralization aims to improve regional finance independency and reduce the fiscal dependency of central government. However, in practice, there are many areas that still rely on the assistance central finance for their regional development. This research aims to discuss the development of regional finance independency and analyze the influence of regional finance independency on economic growth in Banten Province. This research uses descriptive method and panel data on 6 (six) regencies and cities in Banten Province at 2001-2011. The results showed the significantly positive effect of regional finance independency on economic growth and significantly negative effect of balance fund’s ratio on economic growth. Key words: local revenue, economic growth, panel data