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Linearized plastic plate models as Gamma-limits of 3D finite elastoplasticity
The subject of this paper is the rigorous derivation of reduced models for a
thin plate by means of {\Gamma}-convergence, in the framework of finite
plasticity. Denoting by {\epsilon} the thickness of the plate, we analyse the
case where the scaling factor of the elasto-plastic energy is of order
{\epsilon}^(2{\alpha}-2), with {\alpha}>=3. According to the value of {\alpha},
partially or fully linearized models are deduced, which correspond, in the
absence of plastic deformation, to the Von Karman plate theory and the
linearized plate theory.Comment: 19 page
Landsscape diachronic reconstruction in the Tiber Delta during historical time. A holistic approach
The sensitivity of deltas in response to evolutionary factors makes
them important archives of the events that occurred in the entire river basin.
Detailed knowledge of the stratigraphy and morphology, combined
with a set of archaeological, palaeobotanical and historical information,
make possible to reconstruct the diachronic changes of the landscape in
the Tiber delta plain over the past 3000 years taking into account natural
and anthropic forcing. The main factors that contributed to the delta
landscape change are considered following a temporal scansion. Among
the natural factors, we considered climate, sea level rise, tectonic and
local subsidence. Among the human factors we considered the population
density and several human activities, such as farming and breeding
practices, reclamation, construction of ports, canals and salt works. To
evaluate the amount of sediment involved in the delta evolution during
different periods, the BQART model was used. Prior to Roman times
anthropogenic forcing had a lower influence than natural forcing on the
landscape evolution. During the Roman period (between third century
BC-fourth century AD), the delta landscape was severely conditioned by
the human activity. Throughout the Middle Ages and until the first half
of the nineteenth century, a more natural landscape evolved in the delta,
gradually and partially replacing the previous landscape. With the
arrival of the new Italian State a new and impressive landscape change
occurred. The evolution of the Tiber delta landscape appear particularly
affected by anthropogenic forcing when socio-political organization allowed
the control and planning of policy actions
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