67 research outputs found

    Denotational semantics for timed testing

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    In this paper we present a denotational semantics for a timed process algebra, which is fully abstract with respect to the must testing semantics previously developed [Lla96,LdFN96]. The domain of semantic processes is made up of consistent sets of barbs, which generalize the notion of acceptance sets, in such a way that the actions that are offered but not taken in each state are also recorded. the main difficulty when defining this denotational semantics has been that the natural ordering between semantic processes cannot be proved to be complete. So an alternative stronger complete ordering has to be considered, which is proved to be consistent with the original one, in the sense that lubs of chains with respect to the new ordering are also lubs with respect to the original one

    Jugando con el tiempo : semántica de pruebas para algebras de procesos temporizadas

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    en el presente trabajo hemos estudiado la semántica de pruebas para alebras de procesos temporizadas. En primer lugar hemos estudiado un álgebra de procesos temporizada básica, se trata de un lenguaje recursivo, secuencial no determinista. Puesto que las semánticas de pruebas son poco manejables, se hace necesario dar una caracterización alternativa de la misma; nosotros hemos dado una caracterizacion que depende unicamente de la semántica operacional de álgebra. A continuación hemos dotado al álgebra de una semántica denotacional, que ha resultado ser completamente abstracta con respecto a la semántica de pruebas. Seguidamente hemos estudiado una semántica axiomática, puesto que conseguimos probar que esta ultima es correcta y completa con respecto a la semántica detonaciones tenemos inmediatamente que tambien será correcta y completa con respecto a la semántica de pruebas. Puesto que todo lo anterior lo habíamos hecho con un álgebra bastante simple, es necesario introducir operadores mas complejos. En concreto hemos estudiado una serie de operadores que aparecen en la mayoria de las alebras de procesos temporizadas: . El operador de paralelo. El operador de ocultamiento, y. El operador de prefijo mediante acción visible con intervalo de tiempo. Por ultimo hemos estudiado un operador de elección tipo ccs, que tiene los problemas típicos con respecto a la congruenci

    Conformance Verification of Normative Specifications using C-O Diagrams

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    C-O Diagrams have been introduced as a means to have a visual representation of normative texts and electronic contracts, where it is possible to represent the obligations, permissions and prohibitions of the different signatories, as well as what are the penalties in case of not fulfillment of their obligations and prohibitions. In such diagrams we are also able to represent absolute and relative timing constrains. In this paper we consider a formal semantics for C-O Diagrams based on a network of timed automata and we present several relations to check the consistency of a contract in terms of realizability, to analyze whether an implementation satisfies the requirements defined on its contract, and to compare several implementations using the executed permissions as criteria.Comment: In Proceedings FLACOS 2012, arXiv:1209.169

    A Semantic Framework to Debug Parallel Lazy Functional Languages

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    It is not easy to debug lazy functional programs. The reason is that laziness and higherorder complicates basic debugging strategies. Although there exist several debuggers for sequential lazy languages, dealing with parallel languages is much harder. In this case, it is important to implement debugging platforms for parallel extensions, but it is also important to provide theoretical foundations to simplify the task of understanding the debugging process. In this work, we deal with the debugging process in two parallel languages that extend the lazy language Haskell. In particular, we provide an operational semantics that allows us to reason about our parallel extension of the sequential debugger Hood. In addition, we show how we can use it to analyze the amount of speculative work done by the processes, so that it can be used to optimize their use of resources

    Analysis of temporal complex events in sensor networks

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    International audienceIn this paper we introduce a framework for detecting anomalies in the clocks of the different components of a network of sensor stations connected with a central server for measuring of air quality. Local clocks of sensor stations can be advanced/delayed with respect to the central server clock and this situation provokes the inaccuracy in the interpretation of the collected data. We propose a novel approach, supported by a formal representation of the network using fuzzy-timed automata, to precisely represent the expected behaviour of each component of the network. Using fuzzy logic concepts, we can specify admissible mismatches between the clocks. In addition, we apply complex event processing (CEP) technology in order to automatically detect situations of interest while processing the massive amount of data transferred across the network. Specifically, we have designed a collection of CEP patterns that trigger alarms when unexpected differences are observed. We also report the results obtained from the application of our approach to the network during December 2016

    Validación de un Cuestionario Multidimensional de Adaptación a la Enfermedad para Pacientes Renales en Diálisis (CMAE-RD) diseñado a partir de un cuestionario para pacientes oncohematológicos

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    Objectives: The present study aims to explore the psychometric properties of a multidimensional questionnaire to assess adaptation to illness in patients with end stage renal disease under hemodialysis (CMAE-RD for its Spanish acronym). Methods: This instrument was developed to be administered by a psychologist as a semi structured interview and it was adapted from a previous questionnaire for patients with oncohaematologic diseases. A total of 113 patients receiving hemodialysis treatment were interviewed with the CMAE-RD and completed two additional questionnaires with validation purposes: the HADS (to assess anxiety and depression) and the CDRISC-2 (to assess resilience). Results: Internal consistency scores for the areas of the CMAE-RD was comprised between.53 and.70. Evidences of validity related to an external criterion and concurrent validity were obtained for the areas which assess the level of information of the patient and their emotional state. Conclusions: We conclude that the CMAE-RD shows adequate levels of reliability and validity, being a useful measurement tool from the standpoint of health care, as it allows psychologist the needs and resources of renal patients, providing guidance for psychological intervention.Objetivos: El objetivo de este trabajo es estudiar las propiedades psicométricas de un cuestionario multidimensional de adaptación a la enfermedad para pacientes con enfermedad renal en diálisis (CMAE-RD). Métodos: Esta herramienta está diseñada para ser administrada por un profesional de la psicología en forma de entrevista semiestructurada y fue diseñado a partir de un cuestionario previo para pacientes oncohematológicos. Un total de 113 pacientes en hemodiálisis fueron entrevistados mediante el CMAE-RD y completaron dos cuestionarios adicionales con propósitos de validación: el HADS (para evaluar ansiedad y depresión) y el CDRISC-2 (para evaluar resiliencia). Resultados: La consistencia interna para las áreas del CMAE-RD estuvo comprendida entre 0,53 y 0,70, y se obtuvieron evidencias de validez relacionada con un criterio externo y concurrente especialmente para las áreas que evaluaban el grado en que el paciente está informado y su estado de ánimo. Conclusiones: CMAE-RD presenta niveles adecuados de fiabilidad y validez, siendo una herramienta útil desde el punto de vista clínico, pues permite evaluar las necesidades y recursos de los pacientes, guiando la intervención psicológic

    Radon concentration in caves as a proxy for tectonic activity in the cantabrian mountains (Spain)

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    Radon (Rn) constitutes a good geochemical tracer for neotectonic activity in faults since associated fracturing near the surface favours fluid escape to the atmosphere. In this contribution, we measured the Rn concentration in the air inside karst caves to constraints the recent fault activity in the Cantabrian Mountains (N Spain). Rock formations exhumed during the uplifting of the Cantabrian Mountains record a long history of fracturing, which has the potential to connect deeper sources of Rn with the surface. In this regional study, we correlate Rn measurements with cave survey data and geological structures using a Geographic Information Systems. Thirty-four Rn average concentration was recorded by CR-39 detectors during 8 integrated months. The method is applied to the central part of the Cantabrian Mountains that is built on sedimentary and low-grade metamorphic rocks relatively poor in U. Dominant tectonic structures and Rn concentration are examined in 28 cavities. The concentration of Rn values is higher than 0.5 kBq·m-3 in caves developed preferably following fractures with the direction N30oW, being the concentration greater than 0.8 kBq·m-3 in cavities located less than 200±50 m from subvertical faults with such orientation. Rn anomalies point to relative high connectivity along subvertical fault zones NW-trending, preserving fracture connectivity in the most recent structures in the Cantabrian Mountains. Finally, in the study area there is a low but significant radioactive hazard which is associated to fault zones in a fractured rock massif. It contrasts with other active tectonic settings where the radioactive hazard may come from fault movements

    Selecta in libros Aristotelis De Generatione et Corruptione subtilioris doctrinae, quae in Complutensi Academia versatur ...

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    Sign.: [asterisco]4, 2[asterisco]2, A-Z4, 2A4, 2B2, a-c4, d2.Port. con esc. heráldico.Texto a dos col.Numerosos errores de pag.Con paginación propia (13 h) "Liber secundus ...

    Accuracy and precision of agents orientation in an indoor positioning system using multiple infrastructure lighting spotlights and a PSD sensor

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    In indoor localization there are applications in which the orientation of the agent to be located is as important as knowing the position. In this paper we present the results of the orientation estimation from a local positioning system based on position-sensitive device (PSD) sensors and the visible light emitted from the illumination of the room in which it is located. The orientation estimation will require that the PSD sensor receives signal from either 2 or 4 light sources simultaneously. As will be shown in the article, the error determining the rotation angle of the agent with the on-board sensor is less than 0.2 degrees for two emitters. On the other hand, by using 4 light sources the three Euler rotation angles are determined, with mean errors in the measurements smaller than 0.35◦ for the x- and y-axis and 0.16◦ for the z-axis. The accuracy of the measurement has been evaluated experimentally in a 2.5 m-high ceiling room over an area of 2.2 m2 using geodetic measurement tools to establish the reference ground truth values.Junta de Comunidades de Castilla-La Manch
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