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This work is aimed at showing the present capabilities and future potentialities of an imaging radar system that can be mounted onboard flexible aerial platforms, such as helicopters or small airplanes, and may operate in the UHF and VHF frequency bands as Sounder and as Synthetic Aperture Radar (SAR). More specifically, the Sounder operates at 165 MHz, whereas the SAR may operate either at 450 MHz or at 860 MHz. In the work, we present the first results relevant to a set of Sounder and SAR data collected by the radar during a helicopter-borne campaign conducted in 2018 over a desert area in Erfoud, Morocco, just after the conclusion of a system upgrading procedure. In particular, a first analysis of the focusing capabilities of the Sounder mode and of the polarimetric and interferometric capabilities of the SAR mode is conducted. The overall system, originally developed by CO.RI.S.T.A. according to a ASI funding set up in 2010, has been upgraded in the frame of a contract signed in 2015 between ASI and different private and public Italian Research Institutes and Universities, namely CO.RI.S.T.A., IREA-CNR, Politecnico di Milano and University of Trento.

This work aims to describe the characteristics and the status of development, including the results of a first preliminary testing campaign, of a low frequency airborne imaging radar developed in Italy for the Italian Space Agency.

In view of the development of heavy timber seismic-resistant structures, in the context of modern seismic design approach, a possible solution is to allow the timber structure to dissipate a part of the seismic energy. Since timber is a material with an elastic-fragile behaviour, the dissipative function should be delegated to connections, through plastic deformation of steel connectors. However, joints are primary structural elements, with a crucial role in bearing the design loads. Therefore, the role of seismic energy dissipation should be conveniently assumed by ad hoc devices. In this context, the paper deals with the application of fluid viscous dampers (FVD) to timber frames: FVDs dissipate seismic energy, while timber elements and steel connections remain elastic. Specifically, 2D single-storey structures with dissipative bracing systems, equipped with FVDs, in different configurations, are studied, assuming several rates of possible dampings. Non-linear dynamic time history analyses are performed (SAP2000, v18). Results are discussed showing significant reduction of the structural mass compared to the non-dissipative ones, recentering capability of the structures, high dissipative capacity, simpler elastic connections. The reduction of production and maintenance costs follows. All these involve the efficiency of the structural performance and sustainability under earthquakes.