Dependability checking with StoCharts: Is train radio reliable enough for trains?

Performance, dependability and quality of service (QoS) are prime aspects of the UML modelling domain. To capture these aspects effectively in the design phase, we have recently proposed STOCHARTS, a conservative extension of UML statechart diagrams. In this paper, we apply the STOCHART formalism to a safety critical design problem. We model a part of the European Train Control System specification, focusing on the risks of wireless communication failures in future high-speed cross-European trains. Stochastic model checking with the model checker PROVER enables us to derive constraints under which the central quality requirements are satisfied by the STOCHART model. The paper illustrates the flexibility and maturity of STOCHARTS to model real problems in safety critical system design

Hadron masses from dynamical, non-perturbatively O(a) improved Wilson fermions

We present results on light hadron masses from simulations of full QCD and report on experiences in running such simulations on a Hitachi SR8000-F1 supercomputer.Comment: Lattice 2000 (Spectrum), 4 pages, 6 eps figure

A comparative reliability analysis of ETCS train radio communications

StoCharts have been proposed as a UML statechart extension for performance and dependability evaluation, and were applied in the context of train radio reliability assessment to show the principal tractability of realistic cases with this approach. In this paper, we extend on this bare feasibility result in two important directions. First, we sketch the cornerstones of a mechanizable translation of StoCharts to MoDeST. The latter is a process algebra-based formalism supported by the Motor/Möbius tool tandem. Second, we exploit this translation for a detailed analysis of the train radio case study

From StoCharts to MoDeST: a comparative reliability analysis of train radio communications

StoCharts have been proposed as a UML statechart extension for performance and dependability evaluation, and have been applied in the context of train radio reliability assessment to show the principal tractability of realistic cases with this approach. In this paper, we extend on this bare feasibility result in two important directions. First, we sketch the cornerstones of a mechanizable translation of StoCharts to MoDeST. The latter is a process algebra-based formalism supported by the Motor/Möbius tool tandem. Second, we exploit this translation for a detailed analysis of the train radio case study

Finite volume corrections to the binding energy of the X(3872)

The quark mass dependence of hadrons is an important input for lattice calculations. We investigate the light quark mass dependence of the binding energy of the X(3872) in a finite box to next-to-leading order in an effective field theory for the X(3872) with perturbative pions (XEFT). At this order, the quark mass dependence is determined by a quark mass-dependent contact interaction in addition to the one-pion exchange. While there is only a moderate sensitivity to the light quark masses in the region up to twice their physical value, the finite volume effects are significant already at box length as large as 20 fm.Comment: 23 pages, 9 figures, REVTe

Ten-dimensional wave packet simulations of methane scattering

We present results of wavepacket simulations of scattering of an oriented methane molecule from a flat surface including all nine internal vibrations. At a translational energy up to 96 kJ/mol we find that the scattering is almost completely elastic. Vibrational excitations when the molecule hits the surface and the corresponding deformation depend on generic features of the potential energy surface. In particular, our simulation indicate that for methane to dissociate the interaction of the molecule with the surface should lead to an elongated equilibrium C--H bond length close to the surface.Comment: RevTeX 15 pages, 3 eps figures: This article may be found at http://link.aip.org/link/?jcp/109/1966