One of today’s challenges in the framework of ubiquitous computing concerns the design of ambient systems including sensors, smart-phones, interconnected objects, computers, etc. The major difficulty is to propose a compositional adaptation which aims to integrate new features that were not foreseen in the design, remove or exchange entities that are no longer available in a given context. In o...

In this article, three formulations of two phase compositional Darcy flows taking into account phase transitions are compared. The first formulation is the so called natural variable formulation commonly used in reservoir simulation, the second has been introduced in [14] and uses the phase pressures, saturations and component fugacities as main unknowns, and the third is an extension to genera...

Markov decision processes (MDPs) have long been used to model qualitative aspects of systems in the presence of uncertainty. However, much of the literature on MDPs takes a monolithic approach, by modelling a system as a particular MDP; properties of the system are then inferred by analysis of that particular MDP. In this paper we develop compositional methods for reasoning about the qualitativ...

The fast growth in complexity of embedded and software enabled systems requires for automated testing strategies to achieve a high system quality. This raise of complexity is often caused by the distribution of functionality over multiple control units and their connection via a network. We define an extended symbolic transition system (ESTS) and their compositional semantics to reflect these n...

A model coupling a three dimensional gas liquid compositional Darcy flow in a fractured porous medium, and a one dimensional compositional free gas flow is presented. The coupling conditions at the interface between the gallery and the porous medium account for the molar normal fluxes continuity for each component, the gas liquid thermodynamical equilibrium, the gas pressure continuity and the ...

Detailed composition measurements can be a very powerful means of tracing origins, a fact used regularly by forensic scientists and art historians. One of the main motivating factors for making detailed observations of cosmic rays was always the hope that a unique compositional signature could be found which pointed unambiguously to a particular source. This has proven much harder than expected...

1 Marker gene sequencing of microbial communities has generated big datasets 2 of microbial relative abundances varying across environmental conditions, sam3 ple sites and treatments. These data often come with putative phylogenies, 4 providing unique opportunities to investigate how shared evolutionary history 5 a ects microbial abundance patterns. Here, we present a method to identify the 6 p...

The biplot is a widely and powerful methodology used with multidimensional data sets to describe and display the relationships between observations and variables in an easy way. Compositional data consist of positive vectors each of which is constrained to have a constant sum; due to this property standard biplots can not be performed with compositional data, instead of a previous transformatio...

This paper documents the results of in situ analysis of 306 lava paving stones and 74 possible source rocks using pXRF. Data were collected from sites both in the city of Rome—on major roads beyond the city (including the Viae Flaminia, Cassia, Clodia, Praenestina and Appia)—and in the city of Ostia. Comparison of the pXRF data with lava compositional data from the geological literature allows ...

The study analyzes the components of advertising spending for a group of European countries with stable total advertising spending over the period 1994-2007. Three components of advertising spending were considered: Electronic, Print, and Online. Our main objective was to study how the components were restructured within the period under study and to find clusters of similar countries. A specif...