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Campi Flegrei is a Holocene volcanic area in the Campanian Plain (Southern Italy) within the Apennine Chain, a neogenic thrust belt built up since the Middle Miocene. The volcanic complex consists of a c. 12-km-diameter caldera containing several monogenetic volcanoes, the youngest of which (Monte Nuovo) erupted in 1538. Since at least Roman times, the area has also been affected by slow vertical movements (bradiseismic activity). Between 1982 and 1985, this slow motion was interrupted by a period of more rapid displacement which caused a maximum uplift of 180 cm in the town of Pozzuoli. To model the local stress field associated with the uplift, the Angelier inversion technique has been applied using the focal mechanisms of forty-nine earthquakes which occurred between April 1982 and December 1984. The results show that doming coupled with a regional extensional strain can account for the seismic phenomena that affected the area. 相似文献
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Luca Olmi Pietro Bolli Luca Cresci Francesco D’Agostino Massimo Migliozzi Daniela Mugnai Enzo Natale Renzo Nesti Dario Panella Lorenzo Stefani 《Experimental Astronomy》2017,43(3):285-309
The concept of super-resolution refers to various methods for improving the angular resolution of an optical imaging system beyond the classical diffraction limit. Although several techniques to narrow the central lobe of the illumination Point Spread Function have been developed in optical microscopy, most of these methods cannot be implemented on astronomical telescopes. A possible exception is represented by the variable transmittance filters, also known as “Toraldo Pupils” (TPs) since they were introduced for the first time by G. Toraldo di Francia in 1952 (Toraldo di Francia, Il Nuovo Cimento (Suppl.) 9, 426, 1952). In the microwave range, the first successful laboratory test of TPs was performed in 2003 (Mugnai et al. Phys. Lett. A 311, 77–81, 2003). These first results suggested that TPs could represent a viable approach to achieve super-resolution in Radio Astronomy. We have therefore started a project devoted to a more exhaustive analysis of TPs, in order to assess their potential usefulness to achieve super-resolution on a radio telescope, as well as to determine their drawbacks. In the present work we report on the results of extensive microwave measurements, using TPs with different geometrical shapes, which confirm the correctness of the first experiments in 2003. We have also extended the original investigation to carry out full-wave electromagnetic numerical simulations and also to perform planar scanning of the near-field and transform the results into the far-field. 相似文献
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Domenico Gallipoli Agostino Walter Bruno Céline Perlot Joao Mendes 《Acta Geotechnica》2017,12(3):463-478
Much research has been devoted over the past 30 years to the development of construction materials that can lower the environmental and economic costs of buildings over their entire life by reducing embodied energy, minimizing air conditioning needs and cutting down demolition waste. In this respect, raw earth is an attractive material because it is natural and largely available. In its simplest form, this material consists of a compacted mixture of soil and water which is put in place with the least possible transformation. Raw earth construction has been practised in ancient times but has only recently been rediscovered thanks to modern technology, which has improved fabrication efficiency. If properly manufactured, raw earth exhibits comparable mechanical characteristics and better hygro-thermal properties than concrete or fired bricks. After a brief historical overview, we discuss the advantages of raw earth construction in terms of environmental impact, energy consumption and indoor air quality together with the main obstacles to its wider dissemination. We also review the hydro-thermo-mechanical behaviour of raw earth in the context of the recent geotechnical literature, by examining the dependency of key parameters such as strength, stiffness and moisture retention on: (a) material variables (e.g. particle size and mineralogy), (b) manufacturing variables (e.g. density and stabilization) and (c) environmental variables (e.g. pore suction, ambient humidity and temperature). 相似文献
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Quillon Harpham Olalla Gimeno Antonio Parodi Daniele D’Agostino 《Earth Science Informatics》2017,10(2):219-234
The purpose of this paper is to report on and analyse an international consultation into hydro-meteorological e-Science environments with the objective of identifying key functions and features together with exploring show-stopping issues and organisational structure. Transatlantic experiences were compared and contrasted. Including strong participation from both Europe and the USA with high quality responses from experienced practitioners, the consultation was undertaken as part of a joint initiative and took the form of an online questionnaire supported by a set of stakeholder interviews and other discussions. Topics included were functions and features such as provision of numerical models and data, usability, and ease of access; show-stopping issues such as flexibility, reliability and longevity; centralised and distributed structures, and funding models. The results demonstrated a broadly similar set of experiences and implied a future as an evolution of that which exists today. The consultation exercise ran alongside the development of the DRIHM e-Infrastructure which had, in itself, already benefitted from the prior DRIHMS consultation. Results were fed in to the development process at appropriate intervals allowing the consultation to shape the resultant services. 相似文献
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Roberto Viotti Cesare D. La Padula Domenico Nanni Agostino Vignato 《Astrophysics and Space Science》2001,276(1):81-88
We present the basic concepts of the two-mirror, three-reflection optical system (2MTRT), and discuss the important benefits of such a system for space projects: wide ( 2°) correctedand unvignetted FOV, without the use of refractive optics for thefield correction, planarity of the focal surface for an optimizedinstallation of wide area detectors, easy telescope adjustement, small volume and little mass.We also report the results of optical tests made with a 30 cm prototype,equipped with a 2k × 2k CCD camera, and give examples of scientific programmes which can be performed from space and in hostile terrestrial sites such as the Antarctic Plateau. 相似文献
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A new monitoring station for debris flows in the European Alps: first observations in the Gadria basin 总被引：1，自引：0，他引：1
F. Comiti L. Marchi P. Macconi M. Arattano G. Bertoldi M. Borga F. Brardinoni M. Cavalli V. D’Agostino D. Penna J. Theule 《Natural Hazards》2014,73(3):1175-1198
Debris-flow monitoring in instrumented areas is an invaluable way to gather field data that may improve the understanding of these hazardous phenomena. A new experimental site has been equipped in the Autonomous Province of Bozen-Bolzano (Eastern Alps, Italy) for both monitoring purposes and testing early warning systems. The study site (Gadria basin) is a 6.3 km2 catchment subjected to frequent debris flows. The monitoring system in the Gadria basin consists of rain gauges, radar sensors, geophones, video cameras, piezometers and soil moisture probes. Transmission of data and alerts from the instruments exploits in part radio technology. The paper presents the data gathered during the first three years of activity, with two debris-flow events recorded at the station varying in magnitude and characteristics, and discusses the perspectives of debris-flow monitoring and related research. 相似文献