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    Local protection against mountain hazards ? state of the art and future needs

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    International audienceDuring the last decades, settlement activities increased in European mountain regions. Due to the scarceness of areas suitable for development, residential estates were extended into areas endangered by natural hazards such as mass movements. These settlements generally show a considerable vulnerability to tangible assets. Integral risk management strategies to reduce the vulnerability to tangible assets are presented for the assessment of such endangered areas. Conventional mitigation and local structural measures are discussed with respect to the necessary delimitation of endangered areas, the preparedness of people and possible financial prevention. According to different natural hazard processes (flash floods with and without bedload transport, debris flows, land slides, rock falls and avalanches) and various structural elements of buildings, a catalogue of local structural measures is presented with respect to occurring process impacts and protection objectives. Thereby, different local structural measures are classified and recommended according to a possible implementation for newly-erected buildings and for upgrading existing buildings, respectively. Based on these recommendations, future needs for a sustainable and comprehensive reduction of risk in settlement areas endangered by mass movements are outlined. Above all, this includes a prescription of building codes and the re-introduction of an obligatory final inspection of buildings

    Collinear Microstrip Patch Antenna

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    The paper presents a brief overview of the development of so called collinear types of antenna arrays. A new type of this structure in microstrip technology is further introduced. The principle of the antenna operation is explained via surface current distribution of excited modes. Such distribution is reached via geometrical perturbation of a radiating element by slots introduced in such a way that they e liminate radiation from even half current wavelengths . The initial design and optimization of the prototype operating in RFID band (869 MHz) has been performed in planar simulator Zeland IE3D. A prototype has been realized and measured. The reached results show that the presented antenna has directional character as it can be expected due to the proposed technology and the presence of a planar ground plane
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