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The interest on the use of renewable energy resources is increasing, especially wind and hydro powers. To this aim, fuzzy control techniques represent viable strategies that can be employed for this purpose, thanks to the features of these nonlinear dynamic processes working over a wide range of operating conditions, driven by stochastic inputs, excitations and disturbances. Based on past investigations carried out by the authors about the control of wind turbines and hydroelectric power plants, this paper provides some guidelines on the design and application of the control strategies suitable to these energy conversion systems. The working conditions of these energy conversion systems are also taken into account to highlight the reliability and robustness characteristics of the developed control strategies.

This paper evaluates the small- and large-signal characteristics of a single pole double thru (SPDT) RF antenna switch including its insertion loss, isolation and non-linear behavior. It is fabricated on two different types of high resistivity (HR) Silicon-on- Insulator (SOI) substrates: one standard (HR-SOI) and one trap-rich (RFeSI80). Using a special test structure, the contribution of substrate and active devices is separated for both in small- and large-signal. It is shown that by using trap-rich substrate technology, a reduction of more than 17 dB of 2nd harmonic is achieved compared with HR SOI substrate.

There is an increasing interest in NoSQL (Not Only SQL) systems developed in the area of Big Data as candidates for implementing multidimensional data warehouses due to the capabilities of data structuration/storage they offer. In this paper, we study implementation and modeling issues for data warehousing with document-oriented systems, a class of NoSQL systems. We study four different mappings of the multidimensional conceptual model to document data models. We focus on formalization and cross-model comparison. Experiments go through important features of data warehouses including data loading, OLAP cuboid computation and querying. Document-oriented systems are also compared to relational systems.

How efficiently decoding affective information when computational resources and sensor systems are limited? This paper presents a framework for analysis of affective behavior starting with a reduced amount of visual information related to human upper-body movements. The main goal is to individuate a minimal representation of emotional displays based on non-verbal gesture features. The GEMEP (Geneva multimodal emotion portrayals) corpus was used to validate this framework. Twelve emotions expressed by ten actors form the selected data set of emotion portrayals. Visual tracking of trajectories of head and hands was performed from a frontal and a lateral view. Postural/shape and dynamic expressive gesture features were identified and analyzed. A feature reduction procedure was carried out, resulting in a four-dimensional model of emotion expression, that effectively classified/grouped emotions according to their valence (positive, negative) and arousal (high, low). These results show that emotionally relevant information can be detected/measured/obtained from the dynamic qualities of gesture. The framework was implemented as software modules (plug-ins) extending the EyesWeb XMI Expressive Gesture Processing Library and was tested as a component for a multimodal search engine in collaboration with Google within the EU-ICT I-SEARCH project.

International audience; The plethora of data warehouse solutions has created a need comparing these solutions using experimental benchmarks. Existing benchmarks rely mostly on the relational data model and do not take into account other models. In this paper, we propose an extension to a popular benchmark (the Star Schema Benchmark or SSB) that considers non-relational NoSQL models. To avoid data post-processing required for using this data with NoSQL systems, the data is generated in different formats. To exploit at best horizontal scaling, data can be produced in a distributed file system, hence removing disk or partition sizes as limit for the generated dataset. Experimental work proves improved performance of our new benchmark.