138,228 research outputs found
Two Decades of Maude
This paper is a tribute to JosĂ© Meseguer, from the rest of us in the Maude team, reviewing the past, the present, and the future of the language and system with which we have been working for around two decades under his leadership. After reviewing the origins and the language's main features, we present the latest additions to the language and some features currently under development. This paper is not an introduction to Maude, and some familiarity with it and with rewriting logic are indeed assumed.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech
Formalization of Universal Algebra in Agda
In this work we present a novel formalization of universal algebra in Agda. We show that heterogeneous signatures can be elegantly modelled in type-theory using sets indexed by arities to represent operations. We prove elementary results of heterogeneous algebras, including the proof that the term algebra is initial and the proofs of the three isomorphism theorems. We further formalize equational theory and prove soundness and completeness. At the end, we define (derived) signature morphisms, from which we get the contravariant functor between algebras; moreover, we also proved that, under some restrictions, the translation of a theory induces a contra-variant functor between models.Fil: Gunther, Emmanuel. Universidad Nacional de CĂłrdoba. Facultad de MatemĂĄtica, AstronomĂa y FĂsica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Gadea, Alejandro Emilio. Universidad Nacional de CĂłrdoba. Facultad de MatemĂĄtica, AstronomĂa y FĂsica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Pagano, Miguel Maria. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de CĂłrdoba. Facultad de MatemĂĄtica, AstronomĂa y FĂsica; Argentin
Differences in intention to use educational RSS feeds between Lebanese and British students: A multiâgroup analysis based on the technology acceptance model
Really Simple Syndication (RSS) offers a means for university students to receive timely updates from virtual learning environments. However, despite its utility, only 21% of home students surveyed at a university in Lebanon claim to have ever used the technology. To investigate whether national culture could be an influence on intention to use RSS, the survey was extended to British students in the UK. Using the Technology Adoption Model (TAM) as a research framework, 437 students responded to a questionnaire containing four constructs: behavioral intention to use; attitude towards benefit; perceived usefulness; and perceived ease of use. Principle components analysis and structural equation modelling were used to explore the psychometric qualities and utility of TAM in both contexts. The results show that adoption was significantly higher, but also modest, in the British context at 36%. Configural and metric invariance were fully supported, while scalar and factorial invariance were partially supported. Further analysis shows significant differences between perceived usefulness and perceived ease of use across the two contexts studied. Therefore, it is recommended that faculty demonstrate to students how educational RSS feeds can be used effectively to increase awareness and emphasize usefulness in both contexts
Bitcoin: the wrong implementation of the right idea at the right time
This paper is a study into some of the regulatory implications of cryptocurrencies using the CAMPO research framework (Context, Actors, Methods, Methods, Practice, Outcomes). We explain in CAMPO format why virtual currencies are of interest, how self-regulation has failed, and what useful lessons can be learned. We are hopeful that the full paper will produce useful and semi-permanent findings into the usefulness of virtual currencies in general, block chains as a means of mining currency, and the profundity of current âmedia darlingâ currency Bitcoin as compared with the development of block chain generator Ethereum.
While virtual currencies can play a role in creating better trading conditions in virtual communities, despite the risks of non-sovereign issuance and therefore only regulation by code (Brown/Marsden 2013), the methodology used poses significant challenges to researching this âcommunityâ, if BitCoin can even be said to have created a single community, as opposed to enabling an alternate method of exchange for potentially all virtual community transactions. First, BitCoin users have transparency of ownership but anonymity in many transactions, necessary for libertarians or outright criminals in such illicit markets as #SilkRoad. Studying community dynamics is therefore made much more difficult than even such pseudonymous or avatar based communities as Habbo Hotel, World of Warcraft or SecondLife. The ethical implications of studying such communities raise similar problems as those of Tor, Anonymous, Lulzsec and other anonymous hacker communities. Second, the journalistic accounts of BitCoin markets are subject to sensationalism, hype and inaccuracy, even more so than in the earlier hype cycle for SecondLife, exacerbated by the first issue of anonymity. Third, the virtual currency area is subject to slowly emerging regulation by financial authorities and police forces, which appears to be driving much of the early adopter community âundergroundâ. Thus, the community in 2016 may not bear much resemblance to that in 2012. Fourth, there has been relatively little academic empirical study of the community, or indeed of virtual currencies in general, until relatively recently. Fifth, the dynamism of the virtual currency environment in the face of the deepening mistrust of the financial system after the 2008 crisis is such that any research conclusions must by their nature be provisional and transient.
All these challenges, particularly the final three, also raise the motivation for research â an alternative financial system which is separated from the real-world sovereign and which can use code regulation with limited enforcement from offline policing, both returns the study to the libertarian self-regulated environment of early 1990s MUDs, and offers a tantalising prospect of a tool to evade the perils of âprivate profit, socialized riskâ which existing large financial institutions created in the 2008-12 disaster. The need for further research into virtual currencies based on blockchain mining, and for their usage by virtual communities, is thus pressing and should motivate researchers to solve the many problems in methodology for exploring such an environment
Platform Dependent Verification: On Engineering Verification Tools for 21st Century
The paper overviews recent developments in platform-dependent explicit-state
LTL model checking.Comment: In Proceedings PDMC 2011, arXiv:1111.006
A universe of processes and some of its guises
Our starting point is a particular `canvas' aimed to `draw' theories of
physics, which has symmetric monoidal categories as its mathematical backbone.
In this paper we consider the conceptual foundations for this canvas, and how
these can then be converted into mathematical structure. With very little
structural effort (i.e. in very abstract terms) and in a very short time span
the categorical quantum mechanics (CQM) research program has reproduced a
surprisingly large fragment of quantum theory. It also provides new insights
both in quantum foundations and in quantum information, and has even resulted
in automated reasoning software called `quantomatic' which exploits the
deductive power of CQM. In this paper we complement the available material by
not requiring prior knowledge of category theory, and by pointing at
connections to previous and current developments in the foundations of physics.
This research program is also in close synergy with developments elsewhere, for
example in representation theory, quantum algebra, knot theory, topological
quantum field theory and several other areas.Comment: Invited chapter in: "Deep Beauty: Understanding the Quantum World
through Mathematical Innovation", H. Halvorson, ed., Cambridge University
Press, forthcoming. (as usual, many pictures
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