5,645 research outputs found

    Towards Generic Monitors for Object-Oriented Real-Time Maude Specifications

    Get PDF
    Non-Functional Properties (NFPs) are crucial in the design of software. Specification of systems is used in the very first phases of the software development process for the stakeholders to make decisions on which architecture or platform to use. These specifications may be an- alyzed using different formalisms and techniques, simulation being one of them. During a simulation, the relevant data involved in the anal- ysis of the NFPs of interest can be measured using monitors. In this work, we show how monitors can be parametrically specified so that the instrumentation of specifications to be monitored can be automatically performed. We prove that the original specification and the automati- cally obtained specification with monitors are bisimilar by construction. This means that the changes made on the original system by adding monitors do not affect its behavior. This approach allows us to have a library of possible monitors that can be safely added to analyze different properties, possibly on different objects of our systems, at will.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech. Spanish MINECO/FEDER project TIN2014-52034-R, NSF Grant CNS 13-19109

    Pressure effects in PrT2B2C (T = Co, Ni, Pt): Applied and chemical pressure

    Full text link
    High-pressure electrical resistivity, r(T), measurements on intermetallic Pr(Co, Ni, Pt)2B2C compounds were performed down to 2K. At room pressure the r(T) in a-b direction curves for the non superconducting Pr(Co, Ni)2B2C compounds exhibit magnetic correlations at about 10 and 4 K, respectively. At low temperatures, PrCo2B2C shows a large spin-dependent electron scattering in comparison to PrNi2B2C. Under applied pressure the magnetic scattering tends to be suppressed more effectively in PrCo2B2C than in PrNi2 B2C. The low temperature behavior of r(T,P) for PrNi2B2C and PrCo2B2C suggests a spin fluctuations mechanism. In the other hand PrPt2B2C compound shows superconductivity at about 6 K and under pressure its superconducting transition temperature tends to be degraded at a rate dTc/dP = -0.34 K/GPa, as expected in compounds with transition metals. The experimental results in Co, Ni and Pt based compounds are analyzed from the point of view of the external and chemical internal pressure effects

    Grados de Materialidad y Simulaciones Computacionales

    Get PDF
    En este trabajo no voy a abordar exactamente todas estas preguntas, sino más bien trabajaré sobre una más general y, si se quiere, anterior: las SC, ¿pueden considerarse ET?. Y sólo para estupor del lector adelanto que no voy a responder directamente a esta pregunta, por el contrario, voy a aproximarme a ella señalando los peligros que encierra seguir la argumentación de algunos filósofos. En pocas palabras, no voy a indicar si tal o cual argumento es suficiente para decidir el vinculo entre SC y ET, sino voy a señalar qué tipo de argumento no es suficiente para tomar esta decisión. Para llevar a cabo este trabajo hago uso de los argumentos de Francesco Guala quién los presenta de manera radical y condensada, sintetizando argumentos que están presentes en diversas obras sobre la misma temática. En ese sentido, abordar su trabajo no es más que un justificativo para responder de manera más generalizada a discusiones que ya están instauradas en el ambiente

    Observing classical nucleation theory at work by monitoring phase transitions with molecular precision.

    Get PDF
    It is widely accepted that many phase transitions do not follow nucleation pathways as envisaged by the classical nucleation theory. Many substances can traverse intermediate states before arriving at the stable phase. The apparent ubiquity of multi-step nucleation has made the inverse question relevant: does multistep nucleation always dominate single-step pathways? Here we provide an explicit example of the classical nucleation mechanism for a system known to exhibit the characteristics of multi-step nucleation. Molecular resolution atomic force microscopy imaging of the two-dimensional nucleation of the protein glucose isomerase demonstrates that the interior of subcritical clusters is in the same state as the crystalline bulk phase. Our data show that despite having all the characteristics typically associated with rich phase behaviour, glucose isomerase 2D crystals are formed classically. These observations illustrate the resurfacing importance of the classical nucleation theory by re-validating some of the key assumptions that have been recently questioned
    • …
    corecore