Capturing functional and non-functional connector

The CONNECT Integrated Project aims to develop a novel networking infrastructure that will support composition of networked systems with on-the-fly connector synthesis. The role of this work package is to investigate the foundations and verification methods for composable connectors. In this deliverable, we set the scene for the formulation of the modelling framework by surveying existing connector modelling formalisms. We covered not only classical connector algebra formalisms, but also, where appropriate, their corresponding quantitative extensions. All formalisms have been evaluated against a set of key dimensions of interest agreed upon in the CONNECT project. Based on these investigations, we concluded that none of the modelling formalisms available at present satisfy our eight dimensions. We will use the outcome of the survey to guide the formulation of a compositional modelling formalism tailored to the specific requirements of the CONNECT project. Furthermore, we considered the range of non-functional properties that are of interest to CONNECT, and reviewed existing specification formalisms for capturing them, together with the corresponding modelchecking algorithms and tool support. Consequently, we described the scientific advances concerning model-checking algorithms and tools, which are partial contribution towards future deliverables: an approach for online verification (part of D2.2), automated abstraction-refinement for probabilistic realtime systems (part of D2.2 and D2.4), and compositional probabilistic verification within PRISM, to serve as a foundation of future research on quantitative assume-guarantee compositional reasoning (part of D2.2 and D2.4)

Coordinating Parallel Mobile Ambients to Solve SAT Problem in Polynomial Number of Steps

International audienceIn this paper we present a version of mobile ambients, called parMA, having a weak form of replication and a parallel semantics. We investigate how parMA can solve intractable problems in a polynomial number of computational steps. We use parMA to give a semiuniform solution to a well-known strong NP-complete problem, namely to the Boolean satisfiability problem (SAT)

Spatio-temporal model-checking of vehicular movement in public transport systems

We present the use of a novel spatio-temporal model checker to detect problems in the data and operation of a collective adaptive system. Data correctness is important to ensure operational correctness in systems which adapt in response to data. We illustrate the theory with several concrete examples, addressing both the detection of errors in vehicle location data for buses in the city of Edinburgh and the undesirable phenomenon of “clumping” which occurs when there is not enough separation between subsequent buses serving the same route. Vehicle location data are visualised symbolically on a street map, and categories of problems identified by the spatial part of the model checker are rendered by highlighting the symbols for vehicles or other objects that satisfy a property of interest. Behavioural correctness makes use of both the spatial and temporal aspects of the model checker to determine from a series of observations of vehicle locations whether the system is failing to meet the expected quality of service demanded by system regulators

Eighth International Workshop on Laser Ranging Instrumentation

The Eighth International Workshop for Laser Ranging Instrumentation was held in Annapolis, Maryland in May 1992, and was sponsored by the NASA Goddard Space Flight Center in Greenbelt, Maryland. The workshop is held once every 2 to 3 years under differing institutional sponsorship and provides a forum for participants to exchange information on the latest developments in satellite and lunar laser ranging hardware, software, science applications, and data analysis techniques. The satellite laser ranging (SLR) technique provides sub-centimeter precision range measurements to artificial satellites and the Moon. The data has application to a wide range of Earth and lunar science issues including precise orbit determination, terrestrial reference frames, geodesy, geodynamics, oceanography, time transfer, lunar dynamics, gravity and relativity