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<jats:p>The vacuum arc melting method was used to prepare ZrCo<jats:sub>1 − <jats:italic>x</jats:italic> </jats:sub>Cr<jats:sub> <jats:italic>x</jats:italic> </jats:sub> (<jats:italic>x</jats:italic> = 0, 0.025, 0.05, 0.075, 0.1) alloys. Afterward, the crystal structure, hydrogenation kinetics, thermodynamic properties, and disproportionation performance of ZrCo<jats:sub>1 − <jats:italic>x</jats:italic> </jats:sub>Cr<jats:sub> <jats:italic>x</jats:italic> </jats:sub> (<jats:italic>x</jats:italic> = 0−0.1) alloys were investigated. The x-ray diffraction spectra demonstrated that ZrCo<jats:sub>1 − <jats:italic>x</jats:italic> </jats:sub>Cr<jats:sub> <jats:italic>x</jats:italic> </jats:sub> (<jats:italic>x</jats:italic> = 0−0.1) alloys contained ZrCo and ZrCo<jats:sub>2</jats:sub> phases, and their corresponding hydrides consisted of ZrCoH<jats:sub>3</jats:sub> and ZrH phases. The activation behaviors of Cr-substituted samples were significantly promoted. The activation time of ZrCo was 7715 s while that of ZrCo<jats:sub>0.9</jats:sub>Cr<jats:sub>0.1</jats:sub> was 195 s. The improvement of kinetics can be attributed to the catalytic hydrogenation of ZrCr<jats:sub>2</jats:sub>. The activation energy for the hydrogenation of ZrCo was 44.88-kJ⋅mol<jats:sup>−1</jats:sup> H<jats:sub>2</jats:sub> and decreased to 40.34-kJ⋅mol<jats:sup>−1</jats:sup> H<jats:sub>2</jats:sub> for ZrCo<jats:sub>0.95</jats:sub>Cr<jats:sub>0.05</jats:sub>. The plateau pressure and width of the pressure–composition–temperature curves decreased slightly as Cr content increased. The extent of disproportionation of ZrCo was 83.68% after being insulated at 798 K for 10 h and decreased slightly to 70.52% for ZrCo<jats:sub>0.9</jats:sub>Cr<jats:sub>0.1</jats:sub>. The improvement of anti-disproportionation performance can be attributed to increase in the activation energy of disproportionation from 167.46-kJ⋅mol<jats:sup>−1</jats:sup> H<jats:sub>2</jats:sub> for ZrCo to 168.28-kJ⋅mol<jats:sup>−1</jats:sup> H<jats:sub>2</jats:sub> for ZrCo<jats:sub>0.95</jats:sub>Cr<jats:sub>0.05</jats:sub>.</jats:p>

<jats:p>With the increasingly fierce market competition, manufacturing enterprises have to continuously improve their competitiveness through their collaboration and labor division with each other, <jats:italic>i.e.</jats:italic> forming manufacturing enterprise collaborative network (MECN) through their collaboration and labor division is an effective guarantee for obtaining competitive advantages. To explore the topology and evolutionary process of MECN, in this paper we investigate an empirical MECN from the viewpoint of complex network theory, and construct an evolutionary model to reproduce the topological properties found in the empirical network. Firstly, large-size empirical data related to the automotive industry are collected to construct an MECN. Topological analysis indicates that the MECN is not a scale-free network, but a small-world network with disassortativity. Small-world property indicates that the enterprises can respond quickly to the market, but disassortativity shows the risk spreading is fast and the coordinated operation is difficult. Then, an evolutionary model based on fitness preferential attachment and entropy-TOPSIS is proposed to capture the features of MECN. Besides, the evolutionary model is compared with a degree-based model in which only node degree is taken into consideration. The simulation results show the proposed evolutionary model can reproduce a number of critical topological properties of empirical MECN, while the degree-based model does not, which validates the effectiveness of the proposed evolutionary model.</jats:p>

<jats:p>In order to investigate the influence of bottleneck on single-file pedestrian flow, we conduct two different bottleneck experiments. The first one is on ring road, while the second one is on straight route. For the first one, the global density is always set to be 1.5 ped/m. The corresponding critical flow rate for the bottleneck activation is about 0.57 ped/s. The data of the detectors set at different locations, including the velocities and time-headways, show that the amplitude of the oscillation of the stop-and-go waves gradually increases during the upstream propagation. Besides, when the measured flow rates are the same, the different situations in the single-file experiments with and without bottleneck are compared and discussed. For the second one, lower flow rates are used and the bottleneck is always activated. In all the runs, the system can reach one stable state, and the time needed is nearly the same. Inside the stable area, the statistics of pedestrians’ velocities keeps nearly constant in both time and space. Outside this area, when the waiting time is not long (<jats:italic>X</jats:italic> = 10 s), the phenomenon observed is similar to that found on ring road, <jats:italic>e.g.</jats:italic>, the statistics of pedestrians’ velocities also gradually increases during the upstream propagation. This phenomenon is similar to that found in vehicular traffic flow, which shows the universality of different traffic flows. But when the waiting time becomes longer (<jats:italic>X</jats:italic> = 20 s), this situation will be broken since the actions of many pedestrians become much slower. All these results can facilitate understanding more about the influence of bottleneck on single-file pedestrian flow.</jats:p>

<jats:p>Identifying influential nodes in complex networks is essential for network robust and stability, such as viral marketing and information control. Various methods have been proposed to define the influence of nodes. In this paper, we comprehensively consider the global position and local structure to identify influential nodes. The number of iterations in the process of <jats:italic>k</jats:italic>-shell decomposition is taken into consideration, and the improved <jats:italic>k</jats:italic>-shell decomposition is then put forward. The improved <jats:italic>k</jats:italic>-shell decomposition and degree of target node are taken as the benchmark centrality, in addition, as is well known, the effect between node pairs is inversely proportional to the shortest path length between two nodes, and then we also consider the effect of neighbors on target node. To evaluate the performance of the proposed method, susceptible-infected (SI) model is adopted to simulate the spreading process in four real networks, and the experimental results show that the proposed method has obvious advantages over classical centrality measures in identifying influential nodes.</jats:p>

<jats:p>We investigate the dynamical behavior of hybrid virus infection systems with nonlytic immune response in switching environment, which is modeled as a stochastic process of telegraph noise and represented as a multi-state Markov chains. Firstly, The existence of unique positive solution and boundedness of the new hybrid system is proved. Furthermore, the sufficient conditions for extinction and persistence of virus are established. Finally, stochastic simulations are performed to test and demonstrate the conclusions. As a consequence, our work suggests that stochastic switching environment plays a crucial role in the process of virus prevention and treatment.</jats:p>

<jats:p>The scattering states in one-dimensional Hermitian and non-Hermitian potentials are investigated. An analytical solution for the scattering states is presented in terms of Heun functions. It is shown that for some specially chosen parameter conditions, an infinite number of the exact scattering states is obtained. In the Hermitian potentials, they correspond to the reflectionless states. In the non-Hermitian complex potentials with parity-time symmetry, they are the unidirectionally reflectionless states.</jats:p>

<jats:p>Postselected von Neumann measurement characterized by postselection and weak value has been found to possess potential applications in quantum metrology and solved plenty of fundamental problems in quantum theory. As an application of this new measurement technique in quantum optics and quantum information processing, its effects on the features of single-mode radiation fields such as coherent state, squeezed vacuum state and Schrödinger cat sate are investigated by considering full-order effects of unitary evolution. The results show that the conditional probabilities of finding photons, second-order correlation functions, <jats:italic>Q<jats:sub>m</jats:sub> </jats:italic>-factors and squeezing effects of those states after the postselected measurement is significantly changed are comparable with the corresponding initial pointer states.</jats:p>

<jats:p>Quantum sensing has been receiving researcher’s attention these years due to its ultrahigh sensitivity and precision. However, the bandwidth of the sensors may be low, thus limiting the scope of their practical applications. The low-bandwidth problem is conquered by feedback control methods, which are widely utilized in classic control fields. Based on a quantum harmonic oscillator model operating near the resonant point, the bandwidth and sensitivity of the quantum sensor are analyzed. The results give two important conclusions: (a) the bandwidth and sensitivity are two incompatible performance parameters of the sensor, so there must be a trade-off between bandwidth and sensitivity in practical applications; (b) the quantum white noise affects the signal to be detected in a non-white form due to the feedback control.</jats:p>

<jats:p>The optical atomic clocks have the potential to transform global timekeeping, relying on the state-of-the-art accuracy and stability, and greatly improve the measurement precision for a wide range of scientific and technological applications. Herein we report on the development of the optical clock based on <jats:sup>171</jats:sup>Yb atoms confined in an optical lattice. A minimum width of 1.92-Hz Rabi spectra has been obtained with a new 578-nm clock interrogation laser. The in-loop fractional instability of the <jats:sup>171</jats:sup>Yb clock reaches 9.1 × 10<jats:sup>−18</jats:sup> after an averaging over a time of 2.0 × 10<jats:sup>4</jats:sup> s. By synchronous comparison between two clocks, we demonstrate that our <jats:sup>171</jats:sup>Yb optical lattice clock achieves a fractional instability of <jats:inline-formula> <jats:tex-math> <?CDATA $4.60\times {10}^{-16}/\sqrt{\tau }$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mn>4.60</mml:mn> <mml:mo>×</mml:mo> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mo>/</mml:mo> <mml:msqrt> <mml:mi>τ</mml:mi> </mml:msqrt> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_29_9_090601_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>.</jats:p>

<jats:p>We present a time domain hybrid method to realize the fast coupling analysis of transmission lines excited by space electromagnetic fields, in which parallel finite-difference time-domain (FDTD) method, interpolation scheme, and Agrawal model-based transmission line (TL) equations are organically integrated together. Specifically, the Agrawal model is employed to establish the TL equations to describe the coupling effects of space electromagnetic fields on transmission lines. Then, the excitation fields functioning as distribution sources in TL equations are calculated by the parallel FDTD method through using the message passing interface (MPI) library scheme and interpolation scheme. Finally, the TL equations are discretized by the central difference scheme of FDTD and assigned to multiple processors to obtain the transient responses on the terminal loads of these lines. The significant feature of the presented method is embodied in its parallel and synchronous calculations of the space electromagnetic fields and transient responses on the lines. Numerical simulations of ambient wave acting on multi-conductor transmission lines (MTLs), which are located on the PEC ground and in the shielded cavity respectively, are implemented to verify the accuracy and efficiency of the presented method.</jats:p>