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

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

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

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

Dynamics of shallow flows with and without background rotation

Large-scale oceanic and atmospheric flows tend to behave in a two-dimensional way. To further understand such flows, a large scientific effort has been devoted to the study of perfect two-dimensional flows. For the last 30 years, there has been a large interest in experimentally validating the results from numerical and theoretical studies concerning two-dimensional flows, particularly twodimensional turbulence and spatially periodic two-dimensional flows. Inspired by geophysical flows, experimentalists have used stratification, shallow fluid layer configurations, and background rotation to enforce the two-dimensionality of flows in the laboratory. However, as all these methods have shortcomings, it is difficult to achieve a perfectly two-dimensional flow in the laboratory. The work presented in this thesis focuses on two of the common methods used to enforce the two-dimensionality of flows: the shallow layer configuration and background rotation. To further understand the effect of these methods on the two-dimensionality of flows, we studied the dynamics of generic elementary vortical structures in a shallow fluid layer with and without background rotation. Through the analytical and numerical study of a decaying axisymmetric monopolar vortex, we revised the usual argument for considering shallow flowsas two-dimensional. This argument is based on the continuity equation, and it states that the vertical velocity can be neglected if the ratio of vertical to horizontal length scales of the flow is small. By performing numerical simulations and a perturbation analysis for shallow flows, it was shown that this argument is not valid in general, and that the two-dimensionality of the flow does not depend exclusively on the aspect ratio. Instead, it also depends on the dynamics of the flow; particularly, a shallow flow behaves in a two-dimensional way if the flow evolution is dominated by bottom friction over the whole fluid depth. These results were supported by the numerical and experimental study of a more complex flow structure, namely a dipolar vortex, in a shallow fluid layer. For the study of decaying dipolar vortices, numerical simulations were performed using a finite element code. The flow was initialized with a Lamb–Chaplygin dipolar vortex with a Poiseuille-like vertical profile, after which it was left to evolve freely. The 3D structure of the vortex was obtained using the 2 vortex detection criterion. Using this tool, it was observed how the vortex is gradually distorted due to the secondary 3D motions. An experimental investigation of an electromagnetically forced dipolar vortex, where Particle Image Velocimetry (PIV) was used to calculate the velocity field in a horizontal cross-section of the flow, supports the numerically obtained results. It is assumed that flows subjected to strong background rotation behave like two-dimensional flows due to the reduction of gradients in the direction parallel to the rotation axis, as stated by the Taylor–Proudman theorem. This phenomenon results in the formation of columnar structures. In the current work, it was found that the flow can behave in a two-dimensional way as long as the rotation rate is fast enough, irrespective of the aspect ratio. In other words, this is true even if the fluid depth is of the same order as the thickness of the Ekman boundary layer, for which case no columnar structures are formed. This is attributed to the linear coupling between primary and secondary motions. From the study of decaying vortical structures, it was concluded that neither adding background rotation to a shallow flow nor decreasing the depth of a rotating flow necessarily increases the degree of two-dimensionality of the flow. The last two chapters of this thesis are dedicated to the study of a shallow dipolar structure that is continuously driven by time-independent electromagnetic forcing. For a shallow structure without background rotation, it was observed that for weak forcing the flow can be considered indeed as twodimensional. However, every shallow flow, even for very small fluid depths, becomes three-dimensional for a sufficiently high forcing magnitude. An equivalent result was obtained for a similar flow subjected to background rotation. The change in behavior is associated with a change in the vertical profile of the horizontal velocity, which is clearly absent in perfectly two-dimensional flow. The results presented in this thesis confirm that under certain conditions shallow flows and flows subjected to background rotation can behave as a twodimensional flow. However, more importantly, it is shown that there are clear limits to this behavior. This work presents a better understanding of the basic dynamics of shallow flows with and without background rotation and of the extent to which these flows can be considered as quasi-two-dimensional