Search results for "angle"

Protecting entanglement by adjusting the velocities of moving qubits inside non-Markovian environments

2017

Efficient entanglement preservation in open quantum systems is a crucial scope towards a reliable exploitation of quantum resources. We address this issue by studying how two-qubit entanglement dynamically behaves when two atom qubits move inside two separated identical cavities. The moving qubits independently interact with their respective cavity. As a main general result, we find that under resonant qubit-cavity interaction the initial entanglement between two moving qubits remains closer to its initial value as time passes compared to the case of stationary qubits. In particular, we show that the initial entanglement can be strongly protected from decay by suitably adjusting the velocit…

Entanglement trapping in structured environments

2008

The entanglement dynamics of two independent qubits each embedded in a structured environment under conditions of inhibition of spontaneous emission is analyzed, showing entanglement trapping. We demonstrate that entanglement trapping can be used efficiently to prevent entanglement sudden death. For the case of realistic photonic band-gap materials, we show that high values of entanglement trapping can be achieved. This result is of both fundamental and applicative interest since it provides a physical situation where the entanglement can be preserved and manipulated, e.g. by Stark-shifting the qubit transition frequency outside and inside the gap.

Two-qubit entanglement generation through non-Hermitian Hamiltonians induced by repeated measurements on an ancilla

2020

In contrast to classical systems, actual implementation of non-Hermitian Hamiltonian dynamics for quantum systems is a challenge because the processes of energy gain and dissipation are based on the underlying Hermitian system&ndash

$N$ identical particles and one particle to entangle them all

2017

In quantum information W states are a central class of multipartite entangled states because of their robustness against noise and use in many quantum processes. Their generation however remains a demanding task whose difficulty increases with the number of particles. We report a simple scalable conceptual scheme where a single particle in an ancilla mode works as entanglement catalyst of W state for other $N$ separated identical particles. A crucial novel aspect of the scheme, which exploits basically spatial indistinguishability, is its universality, being applicable without essential changes to both bosons and fermions. Our proposal represents a new paradigm within experimental preparati…

Flexural behaviour of RC columns strengthened with steel angles and strips

2011

Modelling steel jacketed RC columns: Remarks by experimental-numerical comparisons

2015

The recent large use of nonlinear seismic assessment techniques requires the definition of highly reliable computational models. The retrofitting or strengthening of RC columns by steel angles and battens is a commonly adopted technique, used to improve strength and deformation capacity of existing RC buildings. In the case of steel angles not directly loaded, the numerical definition of the cross-section model has to be handled carefully since it is affected by more uncertainties. The vertical load carried by the angles is a function of the lateral confinement pressure, the cohesion and the friction coefficient between the materials, parameters which are not always easy to predict. The pap…

Modelling Indoor Radiative Heath Exchanges for Effective People Thermal Comfort and HVAC Design.

2017

Radiative heat exchanges inside buildings are responsible of a relevant part of the thermal balance of people occupying such confined spaces and, in turn, of their thermal comfort sensations. Mean radiant temperature of the internal surfaces is supposed to affect considerably this balance but, usually, it is computed by means of too simplified relationships that significantly affect the comfort evaluations. These simplified approaches can be also accountable of a less effective design of HVAC systems. Unfortunately, an accurate evaluation of the mean radiant temperature, especially when high intensity sources are present in a given internal space, depends on the angle factors between human …

Influence of the vehicle front shape inTeenage Cyclist-Vehicle Crash

2016

In this work the data, obtained for the three vehicles (sedan, SUV and Pick Up), tested in previous works, are compared. Following the results found in the literature, particular emphasis is done on the speed of the teenager cyclist head at the instant of impact and the diagrams of the head speed and the chest obtained in the simulations are shown. The speed of the head is that absolute, and this is used for processing the data and the subsequent determination of the best values of the three geometric actual parameters identified in front of the vehicle. Absolute speed is preferred because using the relative speed respect to vehicle, some amounts that cannot be disregarded are omitted from …

Rateless Codes Performance Analysis in Correlated Channel Model for GEO Free Space Optics Downlinks

2012

An Henstock-Kurzweil type integral on a meausure metric space

2014

We consider an Henstock-Kurzweil type integral defined on a complete measure metric space $X=(X, d)$ endowed with a Radon measure $\mu$ and with a family $\F$ of ``intervals" that satisfies, besides usual conditions, the Vitali covering theorem. In particular, for such integral, we obtain extensions of the descriptive characterization of the classical Henstock-Kurzweil integral on the real line, in terms of $ACG_*$ functions and in terms of variational measures. Moreover we show that, besides the usual Henstock-Kurzweil integral on the real line, such integral includes also the dyadic Henstock-Kurzweil integral, the $GP$-integral and the $s$-HK integral. For this last integral we prove a be…