16 research outputs found
Analysis of the use of tapered graded-index polymer optical fibers for refractive-index sensors
The behavior of tapered graded-index polymer optical fibers is analyzed computationally for different refractive indices of the surrounding medium. This serves to clarify the main parameters affecting their possible performance as refractive-index sensors and extends an existing study of similar structures in glass fibers. The ray-tracing method is employed, its specific implementation is explained, and its results are compared with experimental ones, both from our laboratory and from the literature. The results show that the current commercial graded-index polymer optical fibers can be used to measure a large range of refractive indices with several advantages over glass fibers
Modelling and Simulation of Asynchronous Real-Time Systems using Timed Rebeca
In this paper we propose an extension of the Rebeca language that can be used
to model distributed and asynchronous systems with timing constraints. We
provide the formal semantics of the language using Structural Operational
Semantics, and show its expressiveness by means of examples. We developed a
tool for automated translation from timed Rebeca to the Erlang language, which
provides a first implementation of timed Rebeca. We can use the tool to set the
parameters of timed Rebeca models, which represent the environment and
component variables, and use McErlang to run multiple simulations for different
settings. Timed Rebeca restricts the modeller to a pure asynchronous
actor-based paradigm, where the structure of the model represents the service
oriented architecture, while the computational model matches the network
infrastructure. Simulation is shown to be an effective analysis support,
specially where model checking faces almost immediate state explosion in an
asynchronous setting.Comment: In Proceedings FOCLASA 2011, arXiv:1107.584