Abstract: Embodiments of the present disclosure relate to a method, a device and a computer program product for recovering data. The method comprises in response to receiving a request to recover data from a backup node to a source node, determining a plurality of candidate backup nodes having copies of the data; determining respective performance indicators of the plurality of candidate backup nodes; and determining, from the plurality of candidate backup nodes, the backup node for recovering the data to the source node based on the respective performance indicators of the plurality of candidate backup nodes.

Abstract: The present invention discloses a method for expressing traffic flow characteristics based on a quantum harmonic oscillator model, including: (1) constructing an energy eigenequation of a quantum harmonic oscillator (QHO) for vehicle movement, and converting the energy eigenequation to an Hermite polynomial; (2) solving traffic flow characteristic parameters using K-order Hermite polynomial approximation; and (3) expressing the traffic flow characteristic parameters on a sphere. On the premise of the autonomous decision of a driving strategy by a driver and centering on the objective limitation that the individual accurate state information in the long-distance expressway traffic flow is not observable, the dynamic evolution of the speed and the state of the vehicle is described using a quantum state, the driving state of the vehicle is expressed as the superposition state of three driving states, and the probability of the three states is represented using QHO model parameters.

Abstract: The present invention discloses a method for fitting modes of a traffic flow based on a quantum walk, including: (1) constructing a mode generator based on the quantum walk; (2) preparing multiple modes; (3) screening the modes; and (4) constructing a mapping mechanism between the modes and the traffic volume. The present invention takes the expressway traffic flow as a complex geographic spatial-temporal process formed by aliasing and coupling of a plurality of traffic modes with different structures, and attempts to realize modeling and simulation of the traffic flow from a multi-scale analysis view. Specifically, under a basic framework of an expressway network topological structure, all possible traffic modes in the expressway traffic flow are generated using quantum walks; and under the constraints of the observed traffic volume time series, the modes are screened based on a specific screening rule.