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

Modular DSLs for flexible analysis: An e-Motions reimplementation of Palladio

We address some of the limitations for extending and validating MDE-based implementations of NFP analysis tools by presenting a modular, model-based partial reimplementation of one well-known analysis framework, namely the Palladio Architecture Simulator. We specify the key DSLs from Palladio in the e-Motions system, describing the basic simulation semantics as a set of graph transformation rules. Di erent properties to be analysed are then encoded as separate, parametrised DSLs, independent of the de nition of Palladio. These can then be composed with the base Palladio DSL to generate speci c simulation environments. Models created in the Palladio IDE can be fed directly into this simulation environment for analysis. We demonstrate two main benefits of our approach: 1) The semantics of the simulation and the nonfunctional properties to be analysed are made explicit in the respective DSL speci cations, and 2) because of the compositional de nition, we can add de nitions of new non-functional properties and their analyses.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Matrix orthogonal polynomials satisfying second-order differential equations: Coping without help from group representation theory

AbstractThe method developed in Duran and Grünbaum [Orthogonal matrix polynomials satisfying second order differential equations, Internat. Math. Res. Notices 10 (2004) 461–484] led us to consider polynomials that are orthogonal with respect to weight matrices W(t) of the form e-t2T(t)T*(t), tαe-tT(t)T*(t) and tα(1-t)βT(t)T*(t), with T satisfying T′=(2Bt+A)T, T(0)=I, T′=(A+B/t)T, T(1)=I and T′(t)=(A/t+B/(1-t))T, T(1/2)=I, respectively. Here A and B are in general two non-commuting matrices. To proceed further and find situations where these polynomials satisfied second-order differential equations, we needed to impose commutativity assumptions on the pair of matrices A,B. In fact, we only dealt with the case when one of the matrices vanishes.The only exception to this arose as a gift from group representation theory: one automatically gets a situation where A and B do not commute, see Grünbaum et al. [Matrix valued orthogonal polynomials of the Jacobi type: the role of group representation theory, Ann. Inst. Fourier Grenoble 55 (6) (2005) 2051–2068]. This corresponds to the last of the three cases mentioned above.The purpose of this paper is to consider the other two situations and since now we do not get any assistance from representation theory we make a direct attack on certain differential equations in Duran and Grünbaum [Orthogonal matrix polynomials satisfying second order differential equations, Internat. Math. Res. Notices 10 (2004) 461–484]. By solving these equations we get the appropriate weight matrices W(t), where the matrices A,B give rise to a solvable Lie algebra

Assertion-based Analysis via Slicing with ABETS

[EN] We present ABETS, an assertion-based, dynamic analyzer that helps diagnose errors in Maude programs. ABETS uses slicing to automatically create reduced versions of both a run's execution trace and executed program, reduced versions in which any information that is not relevant to the bug currently being diagnosed is removed. In addition, ABETS employs runtime assertion checking to automate the identification of bugs so that whenever an assertion is violated, the system automatically infers accurate slicing criteria from the failure. We summarize the main services provided by ABETS, which also include a novel assertionbased facility for program repair that generates suitable program fixes when a state invariant is violated. Finally, we provide an experimental evaluation that shows the performance and effectiveness of the system.This work has been partially supported by the EU (FEDER) and Spanish MINECO grant TIN2015-69175-C4-1-R, and by Generalitat Valenciana PROMETEOII/2015/013. J. Sapina was supported by FPI-UPV grant SP2013-0083.Alpuente Frasnedo, M.; Frechina, F.; Sapiña Sanchis, J.; Ballis, D. (2016). Assertion-based Analysis via Slicing with ABETS. Theory and Practice of Logic Programming. 16(5):515-532. https://doi.org/10.1017/S1471068416000375S51553216

Acoustic streaming in pulsating flows through porous media

When a body immersed in a viscous fluid is subjected to a sound wave (or, equivalently, the body oscillates in the fluid otherwise at rest) a rota tional fluid stream develops across a boundary layer nearby the fluid-body interphase. This so-called acoustic streaming phenomenon is responsible for a notable enhancement of heat, mass and momentum transfer and takes place in any process involving two phases subjected to relative oscillations. Understanding the fundamental mechanisms governing acoustic streaming in two-phase flows is of great interest for a wide range of applications such as sonoprocessed fluidized bed reactors, thermoacoustic refrigerators/engines, pulsatile flows through veins/arteries, hemodialysis devices, pipes in off-shore platforms, offshore piers, vibrating structures in the power-generating industry, lab-on-a-chip microfluidics and microgravity acoustic levitation, and solar thermal collectors to name a few. The aim of engineering studies on this vast diversity of systems is oriented towards maximizing the efficiency of each particular process. Even though practical problems are usually approached from disparate disciplines without any apparent linkage, the behavior of these systems is influenced by the same underlying physics. In general, acoustic streaming occurs within the interstices of porous media and usually in the presence of externally imposed steady fluid flows, which gives rise to important effects arising from the interference between viscous boundary layers developed around nearby solid surfaces and the nonlinear coupling between the oscillating and steady flows. This paper is mainly devoted to highlighting the fundamental physics behind acoustic streaming in porous media in order to provide a simple instrument to assess the relevance of this phenomenon in each particular application. The exact microscopic Navier-Stokes equations will be numerically solved for a simplified 2D system consisting of a regular array of oscillating cylinders subjected to an externally imposed steady flow. Results on the pressure drop associated with viscous losses will be compared with predictions from a simple analytical model in which the interaction between the streaming flows developed around the particles and between the oscillating and steady flows are neglected

Differential and Single-Ended Microstrip Lines Loaded with Slotted Magnetic-LC Resonators

This paper is focused on magnetic-LC (MLC) resonators, namely, slotted resonators that can be considered the complementary counterparts of the so-called electric-LC (ELC) resonators. Both resonators exhibit two symmetry planes (i.e., they are bisymmetric), one of them being an electric wall and the other a magnetic wall at the fundamental resonance. Therefore, compared to other electrically small resonators such as folded stepped impedance resonators (SIRs), split ring resonators (SRRs), and their complementary counterparts, MLC and ELC resonators exhibit a very rich phenomenology. In this paper, single-ended microstrip lines and differential microstrip lines loaded with MLC resonators are studied, and potential applications are highlighted