725 research outputs found
Recognisable languages over monads
The principle behind algebraic language theory for various kinds of
structures, such as words or trees, is to use a compositional function from the
structures into a finite set. To talk about compositionality, one needs some
way of composing structures into bigger structures. It so happens that category
theory has an abstract concept for this, namely a monad. The goal of this paper
is to propose monads as a unifying framework for discussing existing algebras
and designing new algebras
Dual Space of a Lattice as the Completion of a Pervin Space
16th International Conference, RAMiCS 2017, Lyon, France, May 15-18, 2017, ProceedingsInternational audienceThis survey paper presents well-known results from a new angle. A Pervin space is a set X equipped with a set of subsets,called the blocks of the Pervin space. Blocks are closed under finite intersections and finite unions and hence form a lattice of subsets of X. Pervin spaces are thus easier to define than topological spaces or (quasi)-uniform spaces. As a consequence, most of the standard topological notions, like convergence and cluster points, specialisation order, filtersand Cauchy filters, complete spaces and completion are much easier to define for Pervin spaces. In particular, the completion of a Pervin space turns out to be the dual space (in the sense of Stone) of the original lattice.We show that any lattice of subsets can be described by a set of inequations of the form u †v, where u and v are elements of its dual space. Applications to formal languages and complexity classes are given.Cet article de synthĂšse prĂ©sente des rĂ©sultats bien connus sous un nouvel angle. Un espace de Pervin est unensemble X Ă©quipĂ© d'un ensemble de parties, appelĂ© les blocs de l'espace de Pervin. Les blocs sont fermĂ©s par intersection finie et union finie et forment ainsi un treillis de parties de X. Les espaces de Pervin sont doncplus faciles Ă dĂ©finir que les espaces topologiques ou les espaces (quasi-)uniformes. Par consĂ©quent, la plupart des notions topologiques, comme la convergence et les points d'adhĂ©rence, l'ordre de spĂ©cialisation, les filtres de Cauchy, les espaces complets et la complĂ©tion sont beaucoup plus faciles Ă dĂ©finir pour les espaces Pervin. En particulier, la complĂ©tion d'un espace Pervin s'avĂšre ĂȘtre l'espace dual (au sens de Stone) du treillis de dĂ©part.Nous montrons que tout treillis de parties peut ĂȘtre dĂ©crit par un ensemble d'inĂ©quations de la forme u †v, oĂč u et v sont des Ă©lĂ©ments de son espace dual. On donne des applications aux langages formels et aux classes de complexitĂ©
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Dig-face monitoring during excavation of a radioactive plume at Mound Laboratory, Ohio
A dig-face monitoring system consists of onsite hardware for collecting information on changing chemical, radiological, and physical conditions in the subsurface soil during the hazardous site excavation. A prototype dig-face system was take to Mount Laboratory for a first trial. Mound Area 7 was the site of historical disposals of {sup 232}Th, {sup 227}Ac, and assorted debris. The system was used to monitor a deep excavation aimed at removing {sup 227}Ac-contaminated soils. Radiological, geophysical, and topographic sensors were used to scan across the excavation dig-face at four successive depths as soil was removed. A 3-D image of the contamination plumes was developed; the radiation sensor data indicated that only a small portion of the excavated soil volume was contaminated. The spatial information produced by the dig-face system was used to direct the excavation activities into the area containing the {sup 227}Ac and to evaluate options for handling the separate {sup 232}Th plume
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Mapping of contamination at Savannah River Site FBWU by INEEL trolley
The Ford Building Waste Unit (FBWU) 643-11G is a Resource Conservation and Recovery Act/Comprehensive Environmental Response Compensation and Liability Act (RCRA/CERCLA) designated site at the Savannah River Site (SRS) in Aiken, South Carolina. Pre-Work Plan Characterization at the FBWU in May 1996 indicated that radiological contamination was present in surface and near surface soils and identified cesium-137, {sup 137}Cs, the unit specific contaminant, as being primarily in the top 15 cm of soil. The Idaho National Engineering and Environmental Laboratory (INEEL) sent the dig-face trolley system to SRS where it demonstrated its capability over a 6.1-m (20 ft.) x 9.6-m (30 ft.) area to rapidly map the contamination on-line with its large area plastic scintillation detector. Also, an extended-range (10 keV to 3 MeV) Ge detector was used at selected locations to identify and quantify the {sup 137}Cs contamination. The coordinate locations of each measurement acquired in either the scanning or fixed position mode was obtained with a survey system based on radial encoders. Topography measurements were also made during measurements to permit correction of field of view and activity concentrations for changes in the ground to detector distance
Changing a semantics: opportunism or courage?
The generalized models for higher-order logics introduced by Leon Henkin, and
their multiple offspring over the years, have become a standard tool in many
areas of logic. Even so, discussion has persisted about their technical status,
and perhaps even their conceptual legitimacy. This paper gives a systematic
view of generalized model techniques, discusses what they mean in mathematical
and philosophical terms, and presents a few technical themes and results about
their role in algebraic representation, calibrating provability, lowering
complexity, understanding fixed-point logics, and achieving set-theoretic
absoluteness. We also show how thinking about Henkin's approach to semantics of
logical systems in this generality can yield new results, dispelling the
impression of adhocness. This paper is dedicated to Leon Henkin, a deep
logician who has changed the way we all work, while also being an always open,
modest, and encouraging colleague and friend.Comment: 27 pages. To appear in: The life and work of Leon Henkin: Essays on
his contributions (Studies in Universal Logic) eds: Manzano, M., Sain, I. and
Alonso, E., 201
Laboratory coupling approach
This chapter deals with the coupling of smart grid laboratories for joint experiments. Therefore, various possibilities are outlined and a reference implementation is introduced. Finally, the vision of a distributed, virtual research infrastructure is presented
Reinventing grounded theory: some questions about theory, ground and discovery
Grounded theoryâs popularity persists after three decades of broad-ranging critique. In this article three problematic notions are discussedââtheory,â âgroundâ and âdiscoveryââwhich linger in the continuing use and development of grounded theory procedures. It is argued that far from providing the epistemic security promised by grounded theory, these notionsâembodied in continuing reinventions of grounded theoryâconstrain and distort qualitative inquiry, and that what is contrived is not in fact theory in any meaningful sense, that âgroundâ is a misnomer when talking about interpretation and that what ultimately materializes following grounded theory procedures is less like discovery and more akin to invention. The procedures admittedly provide signposts for qualitative inquirers, but educational researchers should be wary, for the significance of interpretation, narrative and reflection can be undermined in the procedures of grounded theory
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The EU as a Good Global Actor
This paper outlines an exploratory workshop at City Law School, City, University of London funded by HEIF/ âEUTIPâ Marie SkĆodowska-Curie Innovative Training Network (ITN) on understanding of the EU as a Good Global Actor.1 The EU has as its mission to be a good global governance actor yet is continuously challenged in the world. As a global actor, the EU is both a weak and strong actor in a divergent range of global governance areas. It is not comparable to study the EU as a global trade actor for example to its efforts in human rights, data, cyber or the environment. EU international relations constitutes arguably a booming field of law where the EU appears often to be a victim of its own success. The range of the subjects and objects of EU law continues to expand and the EU is arguably increasingly a victim of its own success, increasingly taking decisions with impacts on third countries or parties, subjecting more entities to sanctions regimes, being bound to consult more entities and have more third countries, parties and entities such as lobbyists interested in the directions of EU law. The assessment of the EU as a global actor includes broad checks on normative action ex ante and ex post facto- yet it is no less harsh. Ex ante metrics of EU global action include court-centred ones such as an opinion from the CJEU on legality of an international agreement, often precluded in most constitutional systems on account of its conflict with pacta sunt servanda. The contours of the principle of the autonomy of EU law have the capacity to put more stringent parameters on EU institutionalised evolutions as to international engagement. How can we assess the EU as a global actor given these realities? The aim of the event was to explore informally the nexus between trade and security, trade and economics and trade and human rights as a future research agenda with input from a variety of scholars It reflected upon four major themes: 1) The EUâs Contribution to the Democratisation of Global Governance 2) Deeper Trade Agreements and New Normative Foundations 3) The EU as a Global Actor in Trade and Fundamental Rights 4) EUâs Trade in the Era of Global Data Flows
The Ontology of Biological Attributes (OBA)-computational traits for the life sciences.
Existing phenotype ontologies were originally developed to represent phenotypes that manifest as a character state in relation to a wild-type or other reference. However, these do not include the phenotypic trait or attribute categories required for the annotation of genome-wide association studies (GWAS), Quantitative Trait Loci (QTL) mappings or any population-focussed measurable trait data. The integration of trait and biological attribute information with an ever increasing body of chemical, environmental and biological data greatly facilitates computational analyses and it is also highly relevant to biomedical and clinical applications. The Ontology of Biological Attributes (OBA) is a formalised, species-independent collection of interoperable phenotypic trait categories that is intended to fulfil a data integration role. OBA is a standardised representational framework for observable attributes that are characteristics of biological entities, organisms, or parts of organisms. OBA has a modular design which provides several benefits for users and data integrators, including an automated and meaningful classification of trait terms computed on the basis of logical inferences drawn from domain-specific ontologies for cells, anatomical and other relevant entities. The logical axioms in OBA also provide a previously missing bridge that can computationally link Mendelian phenotypes with GWAS and quantitative traits. The term components in OBA provide semantic links and enable knowledge and data integration across specialised research community boundaries, thereby breaking silos
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