Electron pumping in graphene mechanical resonators

The combination of high frequency vibrations and metallic transport in graphene makes it a unique material for nano-electromechanical devices. In this letter, we show that graphene-based nano-electromechanical devices are extremely well suited for charge pumping, due to the sensitivity of its transport coefficients to perturbations in electrostatic potential and mechanical deformations, with the potential for novel small scale devices with useful applications

Hidden attractors in fundamental problems and engineering models

Recently a concept of self-excited and hidden attractors was suggested: an attractor is called a self-excited attractor if its basin of attraction overlaps with neighborhood of an equilibrium, otherwise it is called a hidden attractor. For example, hidden attractors are attractors in systems with no equilibria or with only one stable equilibrium (a special case of multistability and coexistence of attractors). While coexisting self-excited attractors can be found using the standard computational procedure, there is no standard way of predicting the existence or coexistence of hidden attractors in a system. In this plenary survey lecture the concept of self-excited and hidden attractors is discussed, and various corresponding examples of self-excited and hidden attractors are considered

The Content-Based Image Retrieval as an Assistance Tool to the Architectural Design

The architectural design requires a research of ideas and a documentation to help the designer in its creation work. It is a domain where the use of pictures (drawing, photography,) is essential, because the information transmitted by photographic images are often more easily to understand than the one transmitted by texts. The goal of this work is to show the help that can bring the research of pictures indexed by visuals criteria, as colour, texture and shape, in the architectural design domain. If weaccept the principle that “an image is better than 10000 words“, we can make the hypothesis that an image research indexed by visual criteria can bring a supplementary help to the designer when he tries to resolve design problems. We tested a research tool resting on image indexation with graphic attributes. Two types of corpora have been used. The first one contains images illustrating building products and the second one shows buildings or parts of buildings, which illustrate the wood architecture domain. The objective of this experiment is to evaluate the relevance of this type of image indexing according to identified users needs. We try to determine which type of visual criteria is the most appropriate to help the designer in the various phases of the design process