A volcanic catastrophe even more devastating than the famous anno Domini 79 Pompeii eruption occurred during the Old Bronze Age at Vesuvius. The 3780-yr-B.P. Avellino plinian eruption produced an early violent pumice fallout and a late pyroclastic surge sequence that covered the volcano surroundings as far as 25 km away, burying land and villages. Here we present the reconstruction of this preh...

As far as the design of SPDs is concerned, the need exists for simplifying its circuit structure in fulfilment of the prerequisite condition of protective reliability. The circuit simplification for SPDs is of benefit to lower the cost of manufacture and reduce the size of chassis. Considering that the traditional SPD that has been extensively used on single-phase AC power supply lines requires...

CaCiiuAing ~lt.0 ,~,o;-e s;irge-pi-o;efiiiie devices located r p y ~ c t i ~ ~ l y rrt the serl@ce e ! ! ~ m c e c>f CI building ar~d near the sensitive equipment is intended to ensure that each device shares the surge stress in an manner commensurate with its rating, to achieve reliable protection of equipment against surges impinging fi-om the utility supply as well as internally generated su...

Metal oxide surge arresters (ZNO) are used widely in power system to protect equipments from over voltages. Non uniform potential distribution leads to the depressed service life and low safe reliability, so grading ring is applied on HV surge arrester order to uniform the electric field distribution. One of the problems of arresters is leakage current in power frequency that different paramet...

near Taruntius Crater appears to be relatively young (~1 Ga) [14]. Of >80 floor-fractured craters mapped by Wilhelms ( Plate 5 in [15]), ~15 have pyroclastic deposits, suggesting that these features may have provided an enhanced environment for explosive volcanic eruption. The spatial association of volcanic eruption sites and impact craters and basins on the Moon is believed to be related to c...

We developed a minimal three-dimensional Cellular Automata (CA) model for pyroclastic flows, generated by collapsing volcanic columns. Our aim is to simulate numerically simple ideal situations and to test that main phenomenological conditions appear correctly in the simulations. Model applications could be very important in order to assess pyroclastic flow hazard in densely inhabited areas. CA...

[1] Exogenous growth of Peléean lava domes involves the addition of lava from a central summit vent and mass wasting on the flanks as rockfalls and pyroclastic flows. These processes were investigated at the Soufrière Hills Volcano, Montserrat, between 30 March and 10 April 2006, using a ground-based imaging millimeter-wave radar, AVTIS, to measure the shape of the dome and talus surface and ro...

Cellular Automata (CA) represent an alternative approach to differential equations to model and simulate complex fluid dynamical systems, whose evolution depends on the local interactions of their constituent parts. A new notion of CA was developed by our research group Empedocles. It permitted to improve significantly an empirical method for modelling macroscopic phenomena, concerning surface ...

This paper summarizes results of a study of porosity, permeability, microstructure and acoustic properties of volcanic and pyroclastic rocks fromCampi Flegrei (CF) andMt. Etna (ET), Italy. We have measured the hydraulic, transport and acoustics properties of 28 room-dry samples at ambient conditions, 25 room-dry samples under confining pressure (up to 60 MPa) and 5 brine saturated samples under...