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Recently, Bauke and Mertens conjectured that the local statistics of energies in random spin systems with discrete spin space should in most circumstances be the same as in the random energy model. This was proven in a large class of models for energies that do not grow too fast with the system size. Considering the example of the generalized random energy model, we show that the conjecture breaks down for energies proportional to the volume of the system, and describe the far more complex behavior that then sets in.

Recently, Bauke and Mertens conjectured that the local statistics of energies in random spin systems with discrete spin space should in most circumstances be the same as in the random energy model. This was proven in a large class of models for energies that do not grow too fast with the system size. Considering the example of the generalized random energy model, we show that the conjecture breaks down for energies proportional to the volume of the system, and describe the far more complex behavior that then sets in.

Latest trend in research tend to fulfill requirements of the most talked about 5G networks. These networks need to be be engineered in terms of cost, energy and spectral efficiency, number of connected devices and latency. Cognitive Radio (CR) is one of the promising techniques to meet the above mentioned requirements that operates at microwave frequencies and exploits underutilized spectrum bands. Universal Filtered Multi-Carrier (UFMC) is a new channel judgment method that use multicarrier modulation scheme. UFMC is consider like an applicant for the 5th Generation of wireless communication systems and replaces OFDM .Latest research indicates that cellular networks are better operated with the novel UFMC with enhanced performance in terms of improved spectral efficiency, less usage of energy as well as latency. However, an emerging area of Information and Communication technology (ICT) are Cognitive radio based Sensor Networks (CSNs). Even basic observations using empirical approach can reveal important observations, especially if the above mentioned latest channel estimation technique (UFMC) , is tried and observed for CSNs. The option of CSNs as test bed is based on abundant use of the supporting in various social and military setups. In this work, part of frequency synchronization and channel estimation are explore and correlate with OFDM and UFMC systems with CSNs as testbed, primarily with a computer-aided software simulator and also with real time experimentation in special laboratory if resources permit.

International audience; Electric vehicle charging stations (EVCSs) come along with great challenges for the power grid due to their highly uncertain load characteristic. This is particularly the case for charging stations located in nonresidential areas, such as commercial centers, company sites, or car-rental stations. For a safe and sustainable operation of the power grid, distribution system operators require reliable load forecasts of such charging stations. In this brief, a robust EVCS management strategy is proposed, which provides a day-ahead upper limit profile of the EVCS's power consumption. In real time, this upper limit profile is strictly respected while guaranteeing-at a configurable probability-the Quality of Service. The strategy is based on randomized algorithms and relies on a statistic occupancy model of the EVCS while not requiring any online forecasts of each EVs' arrival and departure schedules. In a case study based on statistic data, which has been provided by the Euref Campus in Berlin, the feasibility and relevance of the proposed approach are demonstrated.

In the spin glass phase, mean field theory says that the weights of the valleys vary from sample to sample. Exact expressions for the probability laws of these fluctuations are derived, from the random energy model, without recourse to the replica method.

Recently, Bauke and Mertens conjectured that the local statistics of energies in random spin systems with discrete spin space should in most circumstances be the same as in the random energy model. We review some rigorous results confirming the validity of this conjecture. In the context of the SK models, we analyse the limits of the validity of the conjecture for energy levels growing with the volume of the system. In the case of the Generalised Random energy model, we give a complete analysis for the behaviour of the local energy statistics at all energy scales. In particular, we show that, in this case, the REM conjecture holds exactly up to energies EN < βcN, where βc is the critical temperature. We also explain the more complex behaviour that sets in at higher energies.

The Random Energy Model is generalized to treat arbitrary correlations between pairs of energy levels. This Generalized Random Energy Model remains soluble. The sudden freezing which occurs in the RE model can, in the generalized version, become a progressive freezing when temperature decreases Le modele d'energie aleatoire est generalise pour prendre en compte des correlations arbitraires entre paires de niveaux d'energies. Ce modele reste un modele de verre de spin resoluble. Le gel brutal du modele a energies aleatoires peut etre remplace en gel progressif quand on baisse la temperature