α\alpha- and β\beta- Relaxation Dynamics of a fragile plastic crystal

We present a thorough dielectric investigation of the relaxation dynamics of plastic crystalline Freon112, which exhibits freezing of the orientational degrees of freedom into a glassy crystal below 90 K. Among other plastic crystals, Freon112 stands out by being relatively fragile within Angell's classification scheme and by showing an unusually strong $\beta$-relaxation. Comparing the results to those on Freon112a, having only a single molecular conformation, points to the importance of the presence of two molecular conformations in Freon112 for the explanation of its unusual properties.Comment: 17 pages, 6 figure

Classes of complex networks defined by role-to-role connectivity profiles

Interactions between units in phyical, biological, technological, and social systems usually give rise to intrincate networks with non-trivial structure, which critically affects the dynamics and properties of the system. The focus of most current research on complex networks is on global network properties. A caveat of this approach is that the relevance of global properties hinges on the premise that networks are homogeneous, whereas most real-world networks have a markedly modular structure. Here, we report that networks with different functions, including the Internet, metabolic, air transportation, and protein interaction networks, have distinct patterns of connections among nodes with different roles, and that, as a consequence, complex networks can be classified into two distinct functional classes based on their link type frequency. Importantly, we demonstrate that the above structural features cannot be captured by means of often studied global properties

ROSA Analyser: An automatized approach to analyse processes of ROSA

In this work we present the first version of ROSA Analyser, a tool designed to get closer to a fully automatic process of analysing the behaviour of a system specified as a process of the Markovian Process Algebra ROSA. In this first development stage, ROSA Analyser is able to generate the Labelled Transition System, according to ROSA Operational Semantics. ROSA Analyser performance starts with the Syntactic Analysis so generating a layered structure, suitable to then, apply the Operational Semantics Transition rules in the easier way. ROSA Analyser is able to recognize some states identities deeper than the Syntactic ones. This is the very first step in the way to reduce the size of the LTS and then to avoid the state explosion problem, so making this task more tractable. For the sake of better illustrating the usefulness of ROSA Analyser, a case study is also provided within this work.Comment: In Proceedings WS-FMDS 2012, arXiv:1207.1841. Formal model's too

Injection statistics simulator for dynamic analysis of noise in mesoscopic devices

We present a model for electron injection from thermal reservoirs which is applied to particle simulations of one-dimensional mesoscopic conductors. The statistics of injected carriers is correctly described from nondegenerate to completely degenerate conditions. The model is validated by comparing Monte Carlo simulations with existing analytical results for the case of ballistic conductors. An excellent agreement is found for average and noise characteristics, in particular, the fundamental unities of electrical and thermal conductances are exactly reproduced.Comment: 4 pages, revtex, 4 PS figures, accepted Semicond. Sci. Techno