83 research outputs found
Re-Shaping Hysteresis: Seismic Semi-Active Control Experiments for a 1/5th Scale Structure
Semi-active resetable devices can improve seismic response. Novel 2-4 devices
independently control each device chamber to customise structural hysteresis loops to
reduce both displacement and base shear demands. Here, 2-4 devices are experimentally
validated on a one-fifth scale test structure weighing 35kN with a natural period of 0.6
seconds. Four seismic inputs over a wide range of intensity levels are use in 27 tests.
Results for resetable semi-active devices that modify hysteretic behaviour using different
control laws are compared to spectral response analyses that predict ~30-50% peak
displacement reductions. Fully uncontrolled tests were also done for lower intensity
ground motions, along with fail-safe valves-open tests. Results show 25-50% peak
displacement reductions compared to the valves open case, depending on the semi-active
control law used and matching spectral analysis results. Additionally, a semi-active
control law designed to simultaneously reduce base shear reduces it 10-20%. In contrast,
10-20% increases are seen for other approaches, as predicted. Overall, these are the first
large-scale tests of this type of novel resetable devices. The results validate prior
simulation and spectral analyses, and clearly show the potential. Finally, semi-active
methods that re-shape hysteresis to control response and simultaneously limit base shear
demand, are experimentally demonstrated for the first time
Operations management nella produzione e nei servizi
Il volume illustra le scelte strategiche e gestionali nelle operations e nella produzione di beni e servizi. Vengono descritte, con esempi e casi, tutte le principali tecniche di gestione applicabili nell'operations managemen
Operations Management nella produzione e nei servizi
Il volume illustra le scelte strategiche e gestionali nelle operations e nella produzione di beni e servizi. Vengono descritte, con esempi e casi, tutte le principali tecniche di gestione applicabili nell'operations managemen
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