913 research outputs found
Closure to "testing the Stage-Discharge Relationship in Sloping SMBF Flumes" by Francesco Giuseppe Carollo and Vincenzo Pampalone
No full textThis is the closure to the discussions on the paper "Testing the Stage-Discharge Relationship in Sloping SMBF Flumes"
Spreading of correlations in Markovian open quantum systems
No full textUnderstanding the spreading of quantum correlations in out-of-equilibrium many-body systems is one of the major challenges in physics. For isolated systems, a hydrodynamic theory explains the origin and spreading of entanglement via the propagation of quasiparticle pairs. However, when systems interact with their surrounding much less has been established. Here we show that the quasiparticle picture remains valid for open quantum systems: While information is still spread by quasiparticles, the environment modifies their correlation and introduces incoherent and mixing effects. For free fermions with gain/loss dissipation we provide formulas fully describing incoherent and quasiparticle contributions in the spreading of entropy and mutual information. Importantly, the latter is not affected by entanglement of the system with the external environment. The mutual information is exponentially damped at short times and eventually vanishes signaling the onset of a classical limit. The behavior of the logarithmic negativity is similar and this scenario is common to other dissipations. For weak dissipation, the presence of quasiparticles underlies remarkable scaling behaviors
Hydrodynamics of quantum entropies in Ising chains with linear dissipation
No full textWe study the dynamics of quantum information and of quantum correlations after a quantum quench, in transverse field Ising chains subject to generic linear dissipation. As we show, in the hydrodynamic limit of long times, large system sizes, and weak dissipation, entropy-related quantities - such as the von Neumann entropy, the Rényi entropies, and the associated mutual information - admit a simple description within the so-called quasiparticle picture. Specifically, we analytically derive a hydrodynamic formula, recently conjectured for generic noninteracting systems, which allows us to demonstrate a universal feature of the dynamics of correlations in such dissipative noninteracting system. For any possible dissipation, the mutual information grows up to a time scale that is proportional to the inverse dissipation rate, and then decreases, always vanishing in the long time limit. In passing, we provide analytic formulas describing the time-dependence of arbitrary functions of the fermionic covariance matrix, in the hydrodynamic limit
Life cycle costing della catena di gestione dei rifiuti da costruzione e demolizione
No full textIl seguente lavoro si pone l’obiettivo di valutare i costi della demolizione selettiva e dell’uso degli aggregati riciclati attraverso l'applicazione della metodologia dell’Environmental Life Cycle Costing (eLCC). L'analisi eLCC ha incluso i costi preliminari, di acquisizione macchinari, operativi e di conferimento relativi all'intera catena di gestione dei rifiuti da costruzione e demolizione (C&D). Sulla base dei risultati ottenuti è stato possibile delineare alcuni scenari prevedendo meccanismi di incentivazione a beneficio della demolizione selettiva e dell’uso degli aggregati riciclati per favorire il raggiungimento di un’economia circolare nel settore delle costruzioni
Noninteracting fermionic systems with localized losses: Exact results in the hydrodynamic limit
No full textWe investigate the interplay between unitary and nonunitary dynamics after a quantum quench in a noninteracting fermionic chain. In particular, we consider the effect of localized loss processes, for which fermions are added and removed incoherently at the center of the chain. We focus on the hydrodynamic limit of large distances from the localized losses and of long times, with their ratio being fixed. In this limit, the localized losses gives rise to an effective imaginary delta potential (nonunitary impurity), and the time-evolution of the local correlation functions admits a simple hydrodynamic description in terms of the fermionic occupations in the initial state and the reflection and transmission amplitudes of the impurity. We derive this hydrodynamic framework from the ab initio calculation of the microscopic dynamics. This allows us to analytically characterize the effect of losses for several theoretically relevant initial states, such as a uniform Fermi sea, homogeneous product states, or the inhomogeneous state obtained by joining two Fermi seas. In this latter setting, when both gain and loss processes are present, we observe the emergence of exotic nonequilibrium steady states with stepwise uniform density profiles. In all instances, for strong loss and gain rates the coherent dynamics of the system is arrested, which is a manifestation of the celebrated quantum Zeno effect
Life cycle costing approach for construction and demolition waste management chain: methodology of data collection and organization
No full textLCC analysis of construction and demolition waste management chain
No full textIn Italy, despite most of the mineral waste from construction and demolition (C&D)
activities is sent for recovery, we are still a long way from reaching the circular economy in the
building sector. Natural cave-generated aggregates are still favoured over recovered ones, implying
huge volumes of unsold recycled materials aside from the decrease of natural materials, whose supply
can be more restricted by time. In this work, the implementation of the Life Cycle Costing (LCC)
methodology will provide the basis for the political decision-makers' economic appraisal to stimulate
the market for recycled aggregates.. The LCC study assesses the preliminary, machinery acquisition,
operating, and disposal costs associated with the whole C&D value chain, from inert waste production
in demolition yards through the usage of recycled aggregates generated
Life cycle costing of construction and demolition waste management chain
No full textAccording to recent studies, in Italy, most of the mineral waste from construction and demolition (C&D)
activities is already sent for recovery, but the closure of the circle, necessary for the realization of the circular
economy, is not yet reached because there are still obstacles that prevent the widespread use of the secondary
resources produced in the recycling activities. In Italy, natural cave-generated aggregates are still preferred in
place of recovered ones and this implies large amounts of recycled materials that remain unsold, other than the
reduction of natural goods, of which availability can be more and more limited by time. This work deepens the
advantages of using recycled aggregates from the economic point of view, through the application of the Life
Cycle Costing (LCC) methodology.
The LCC analysis evaluates the preliminary, the machinery acquisition, the operating, and the disposal costs
relating to the entire C&D value chain, going from the generation of inert waste in demolition yards to the use of
the recycled aggregates produced. The results of this work will be the starting point for the proposal of incentive
mechanisms or reward criteria, whose implications are relevant to policymakers
Quantum spin chain dissipative mean-field dynamics
No full textWe study the emergent dynamics resulting from the infinite volume limit of the mean-field dissipative dynamics of quantum spin chains with clustering, but not time-invariant states. We focus upon three algebras of spin operators: the commutative algebra of mean-field operators, the quasi-local algebra of microscopic, local operators and the collective algebra of fluctuation operators. In the infinite volume limit, mean-field operators behave as time-dependent, commuting scalar macroscopic averages while quasi-local operators, despite the dissipative underlying dynamics, evolve unitarily in a typical non-Markovian fashion. Instead, the algebra of collective fluctuations, which is of bosonic type with time-dependent canonical commutation relations, undergoes a time-evolution that retains the dissipative character of the underlying microscopic dynamics and exhibits non-linear features. These latter disappear by extending the time-evolution to a larger algebra where it is represented by a continuous one-parameter semigroup of completely positive maps. The corresponding generator is not of Lindblad form and displays mixed quantum-classical features, thus indicating that peculiar hybrid systems may naturally emerge at the level of quantum fluctuations in many-body quantum systems endowed with non time-invariant states
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