Search results for "Criteri"
showing 10 items of 807 documents
Subsurface treatment of a contact subjected to a hertz pressure
2013
Abstract The study proposes an approach allowing the favorable modification of the stresses field of a structure subjected to a Hertzian contact. It is based on the study of a classic Hertzian contact in the presence of subsurface circular defects. The idea is to limit the field of tangential stresses without large increasing of the global stress (Von Mises) of the system. The location of the defects is made according to the mechanical parameters of the contact (Fn, has, z). The results of the numerical calculations (FEM) are compared with photoelastic measurements and highlight an excellent correlation. The location of the defect on the symmetry axis (x=0) is the dominating parameter for t…
Observation of light-by-light scattering in ultraperipheral Pb+Pb collisions with the ATLAS detector
2019
This Letter describes the observation of the light-by-light scattering process, γγ→γγ, in Pb+Pb collisions at √sNN=5.02 TeV. The analysis is conducted using a data sample corresponding to an integrated luminosity of 1.73 nb−1, collected in November 2018 by the ATLAS experiment at the LHC. Light-by-light scattering candidates are selected in events with two photons produced exclusively, each with transverse energy EγT>3 GeV and pseudorapidity |ηγ|<2.4, diphoton invariant mass above 6 GeV, and small diphoton transverse momentum and acoplanarity. After applying all selection criteria, 59 candidate events are observed for a background expectation of 12±3 events. The observed excess of events…
Discreteness effects on a sine-Gordon breather
1991
We employ collective-variable theory to describe the dynamics of a breather excitation in its center-of-mass frame in continuous and discrete systems of one spatial dimension. The exact equations of motion for the collective variable and coupled phonon field are derived for any system which supports breatherlike excitations that have even spatial parity where the collective variable represents half the distance between the breather subkinks. We then specialize the theory to the sine-Gordon (SG) case. For the continuum SG system we derive the exact effective potential in terms of the collective variable and discuss the relativistic effects on the breather subkinks which are quite different t…
Steady-state entanglement activation in optomechanical cavities
2014
Quantum discord, and a number of related indicators, are currently raising a relentless interest as a novel paradigm of non-classical correlations beyond entanglement. Beside merely fundamental aspects, various works have shown that discord is a valuable -- so far largely unexplored -- resource in quantum information processing. Along this line, quite a striking scheme is {entanglement activation}. An initial amount of discord between two disentangled parties of a multipartite system affects the dynamics so as to establish entanglement across a bipartition, which would not arise otherwise. To date, such a process was proven to be achievable only dynamically, i.e., with no guarantee of a sta…
Controllable Gaussian-Qubit Interface for Extremal Quantum State Engineering
2010
We study state engineering through bilinear interactions between two remote qubits and two-mode Gaussian light fields. The attainable two-qubit states span the entire physically allowed region in the entanglement-versus-global-purity plane. Two-mode Gaussian states with maximal entanglement at fixed global and marginal entropies produce maximally entangled two-qubit states in the corresponding entropic diagram. We show that a small set of parameters characterizing extremally entangled two-mode Gaussian states is sufficient to control the engineering of extremally entangled two-qubit states, which can be realized in realistic matter-light scenarios.
EXPERIMENTAL STUDY ON THE FLUID FLOWIN THE CONDUCTS
2018
Fluids are high mobility environments that, under the action of external forces, are continuously and irreversibly deformed. The flow of fluid through a pipe is ensured by a pressure difference between its ends. The presented paper aims to experimentally determine the velocity profile of flowing a Newtonian fluid through a circular section pipe by measuring the local speed at five points on the pipe radius.
La multifunzionalità in agricoltura: dai valori delle aree agricole al concetto di multifunzionalità e relazione con la pianificazione territoriale.
2014
La convivenza di più attività in aree agricole è sempre esistita ma la formalizzazione del principio di multifunzionalità applicata all’agricoltura è un passaggio importante che promuove la compresenza di più attività e offerte che si configurano con diversi livelli complessità, divenendo servizi al territorio e alla persona e riuscendo a riattivare territori a rischio. L’introduzione della multifunzionalità in agricoltura ha avuto un grande slancio a partire dalla crisi economica dell’agricoltura tradizionale e, quindi, i temi economici ricorrono spesso nell’analisi effettuata per farli incontrare e interagire con questioni culturali, sociali, ambientali. L’ottica da cui si indaga è quella…
APROS-NIMBUS: Dynamic Process Simulator and Interactive Multiobjective Optimization in Plant Automation
2013
Abstract Virtual commissioning of chemical plants often involves a dynamic simulator and an optimization method. This paper demonstrates the integration of APROS, a dynamic process simulator and IND-NIMBUS, an interactive multiobjective optimization software. We implement a multiobjective concentration control problem in APROS involving conflicting objectives and employ a decision maker to interact with IND-NIMBUS and express his preference information to finally obtain his most preferred solution. The results of this study show that APROS and IND-NIMBUS can be integrated and an interactive multiobjective optimization method can help the decision maker in exploring trade-offs among conflict…
Energy and environmental analysis of marble productive sites: «by phases» and «by single process» combined approach
2018
Energy Procedia 00 (20 1 8 ) 000 – 000 73rd Conference of the Italian Thermal Machines Engineering Association, ATI 2018, Pisa, Italy, 12 Sep 2018 - 14 Sep 2018; Italy : Elsevier Ltd. (2018).
Applied Mathematics versus Fluid Dynamics
2018
This paper investigates scientific, institutional, and political conflict and collaboration between two different disciplines in the first part of the 20th century: applied mathematics and fluid dynamics. It argues for the catalytic role of Richard von Mises (1883–1953) in this process and analyzes the reasons for von Mises’s considerable fame in the former and limited posthumous reputation in the latter field. I argue that von Mises’s contributions to fluid dynamics and aerodynamics suffered chiefly from two somewhat interconnected deficiencies compared to the work of his principal competitors. There was, on the one hand, von Mises’s methodological preference for applied mathematics as opp…