Structural and robustness properties of smart-city transportation networks
The concept of smart city gives an excellent resolution to construct and develop modern cities, and also demands infrastructure construction. How to build a safe, stable, and highly efficient public transportation system becomes an important topic in the process of city construction. In this work, we study the structural and robustness properties of transportation networks and their sub-networks. We introduce a complementary network model to study the relevance and complementarity between bus network and subway network. Our numerical results show that the mutual supplement of networks can improve the network robustness. This conclusion provides a theoretical basis for the construction of public traffic networks, and it also supports reasonable operation of managing smart cities.
A universal function of creep rate
In this paper, we derive a universal function from a model based on statistical mechanics developed recently, and show that the function is well fitted to all the available experimental data which cannot be described by any function previously established. With the function predicting creep rate, it is unnecessary to consider which creep mechanism dominates the process, but only perform several experiments to determine the three constants in the function. It is expected that the new function would be widely used in industry in the future.
Three-dimensional coherent diffraction imaging of Mie-scatteringspheres by laser single-orientation measurement
Three-dimensional imaging with single orientation is a potential and novel technique. We successfully demonstrate that three-dimensional (3D) structure can be determined by a single orientation diffraction measurement for a phase object of double-layer Mie-scattering silica spheres on a Si3N4 membrane. Coherent diffraction pattern at high numerical aperture was acquired with an optical laser, and the oversampled pattern was projected from a planar detector onto the Ewald sphere. The double-layered spheres are reconstructed from the spherical diffraction pattern and a 2D curvature-corrected pattern, which improve convergence speed and stability of reconstruction.
Beam propagation method for wide-fieldnonlinear wave mixing microscope
We develop a nonlinear beam propagation method for signal generation in inhomogeneous medium for wide-field nonlinear wave mixing microscope. Experimental results performed in wide-field coherent anti-Stokes Raman imaging have shown good agreement with the developed theory.
Electronic mobility in the high-carrier-density limit ofion gel gated IDTBT thin film transistors
Robust H∞ control of uncertain systems with two additive time-varying delays
Nonlocal symmetries, consistent Riccati expansion integrability, and their applications of the (2+1)-dimensional Broer-Kaup-Kupershmidt system
Second-order two-scale analysis and numerical algorithms for the hyperbolic-parabolic equations with rapidly oscillating coefficients
A new model for algebraic Rossby solitary waves in rotation fluid and its solution
Rigidity based formation tracking for multi-agent networks
This paper considers the formation tracking problem under a rigidity framework, where the target formation is specified as a minimally and infinitesimally rigid formation and the desired velocity of the group is available to only a subset of the agents. The following two cases are considered: the desired velocity is constant, and the desired velocity is time-varying. In the first case, a distributed linear estimator is constructed for each agent to estimate the desired velocity. The velocity estimation and a formation acquisition term are employed to design the control inputs for the agents, where the rigidity matrix plays a central role. In the second case, a distributed non-smooth estimator is constructed to estimate the time-varying velocity, which is shown to converge in a finite time. Theoretical analysis shows that the formation tracking problem can be solved under the proposed control algorithms and estimators. Simulation results are also provided to show the validity of the derived results.
A novel observer design method for neural mass models
Neural mass models can simulate the generation of electroencephalography (EEG) signals with different rhythms, and therefore the observation of the states of these models plays a significant role in brain research. The structure of neural mass models is special in that they can be expressed as Lurie systems. The developed techniques in Lurie system theory are applicable to these models. We here provide a new observer design method for neural mass models by transforming these models and the corresponding error systems into nonlinear systems with Lurie form. The purpose is to establish appropriate conditions which ensure the convergence of the estimation error. The effectiveness of the proposed method is illustrated by numerical simulations.
Distributed H∞ control of multi-agent systems with directed networks
Improving the secrecy rate by turning foes to allies: An auction scheme
Ground-state information geometry and quantum criticality in an inhomogeneous spin model
Time evolution of negative binomial optical field ina diffusion channel
Phase effect on dynamics of quantum discord modulated by interaction between qubits
Reduction of entropic uncertainty in entangled qubits systemby local JJ-symmetric operation
We investigate the quantum-memory-assisted entropic uncertainty for an entangled two-qubit system in a local quantum noise channel with JJ-symmetric operation performing on one of the two particles. Our results show that the quantum-memory-assisted entropic uncertainty in the qubits system can be reduced effectively by the local JJ-symmetric operation. Physical explanations for the behavior of the quantum-memory-assisted entropic uncertainty are given based on the property of entanglement of the qubits system and the non-locality induced by the re-normalization procedure for the non-Hermitian JJ-symmetric operation.
Countermeasure against probabilistic blinding attack in practical quantum key distribution systems
In a practical quantum key distribution (QKD) system, imperfect equipment, especially the single-photon detector, can be eavesdropped on by a blinding attack. However, the original blinding attack may be discovered by directly detecting the current. In this paper, we propose a probabilistic blinding attack model, where Eve probabilistically applies a blinding attack without being caught by using only an existing intuitive countermeasure. More precisely, our countermeasure solves the problem of how to define the bound in the limitation of precision of current detection, and then we prove security of the practical system by considering the current parameter. Meanwhile, we discuss the bound of the quantum bit error rate (QBER) introduced by Eve, by which Eve can acquire information without the countermeasure.
Controlled mutual quantum entity authentication using entanglement swapping
Effects of intrinsic decoherence on various correlations and quantum dense coding in a two superconducting charge qubit system
The influence of intrinsic decoherence on various correlations and dense coding in a model which consists of two identical superconducting charge qubits coupled by a fixed capacitor is investigated. The results show that, despite the intrinsic decoherence, the correlations as well as the dense coding channel capacity can be effectively increased via the combination of system parameters, i.e., the mutual coupling energy between the two charge qubits is larger than the Josephson energy of the qubit. The bigger the difference between them is, the better the effect is.
Spin-orbit coupled Bose-Einstein condensates withRydberg-dressing interaction
Interaction between Rydberg atoms can be used to control the properties of interatomic interaction in ultracold gases by weakly dressing the atoms with a Rydberg state. Here we investigate the effect of the Rydberg-dressing interaction on the ground-state properties of a Bose-Einstein condensate imposed by Raman-induced spin-orbit coupling. We find that, in the case of SU(2)-invariant s-wave interactions, the gas is only in the plane-wave phase and the zero-momentum phase is absent. In particular, we also predict an unexpected magnetic stripe phase composed of two plane-wave components with unequal weight when s-wave interactions are non-symmetric, which originates from the Rydberg-dressing interaction.
Reduced one-body density matrix of Tonks–Girardeaugas at finite temperature
Invariance of specific mass increment in the case ofnon-equilibrium growth
A cellular automaton model for the ventricular myocardium considering the layer structure
Off-policy integral reinforcement learning optimal tracking control for continuous-time chaotic systems
This paper estimates an off-policy integral reinforcement learning (IRL) algorithm to obtain the optimal tracking control of unknown chaotic systems. Off-policy IRL can learn the solution of the HJB equation from the system data generated by an arbitrary control. Moreover, off-policy IRL can be regarded as a direct learning method, which avoids the identification of system dynamics. In this paper, the performance index function is first given based on the system tracking error and control error. For solving the Hamilton-Jacobi-Bellman (HJB) equation, an off-policy IRL algorithm is proposed. It is proven that the iterative control makes the tracking error system asymptotically stable, and the iterative performance index function is convergent. Simulation study demonstrates the effectiveness of the developed tracking control method.
Prescribed performance synchronization for fractional-order chaotic systems
Cooperative adaptive bidirectional control of a train platoon for efficient utility and string stability
Invariance of specific mass increment in the case of non-equilibrium growth
Standardization of proton-induced x-ray emission technique for analysis of thick samples
Covalent intermolecular interaction of the nitric oxide dimer (NO)2
Characteristics of Nb/Al superconducting tunnel junctions fabricated using ozone gas
Theoretical approach to the study of vibrational effects on strong field ionization of molecules with alignment-dependent tunneling ionization rates
Charge transfer of He2+ with H in a strong magnetic field
By solving a time-dependent Schrödinger equation (TDSE), we studied the electron capture process in the He2++H collision system under a strong magnetic field in a wide projectile energy range. The strong enhancement of the total charge transfer cross section is observed for the projectile energy below 2.0 keV/u. With the projectile energy increasing, the cross sections will reduce a little and then increase again, compared with those in the field-free case. The cross sections to the states with different magnetic quantum numbers are presented and analyzed where the influence due to Zeeman splitting is obviously found, especially in the low projectile energy region. The comparison with other models is made and the tendency of the cross section varying with the projectile energy is found closer to that from other close coupling models.
Fast thermometry for trapped atoms using recoil-induced resonance
We have employed recoil-induced resonance (RIR) with linewidth on the order of 10 kHz to demonstrate the fast thermometry for ultracold atoms. We theoretically calculate the absorption spectrum of RIR which agrees well with the experimental results. The temperature of the ultracold sample derived from the RIR spectrum is T=84± 4.5 μK, which is close to 85 μK that measured by the method of time-of-flight absorption imaging. To exhibit the fast measurement advantage in applying RIR to the ultracold atom thermometry, we study the dependence of ultracold sample temperature on the trapping beam frequency detuning. This method can be applied to determine the translational temperature of molecules in photoassociation dynamics.
Numerical simulation of the coupling of ultra-wide band electromagnetic pulse into landmine by aperture
Tunable terahertz radiation from arbitrary profile dielectric grating coated with graphene excited by an electron beam
Distribution characteristics of intensity and phase vortices ofspeckle fields produced by N-pinhole random screens
Coupled thermal-optic effects and electrical modulation mechanism of birefringence crystal with Gaussian laser incidence
We study the Gaussian laser transmission in lithium niobate crystal (LiNbO3) by using the finite element method to solve the electromagnetic field's frequency domain equation and energy equation. The heat generated is identified by calculating the transmission loss of the electromagnetic wave in the birefringence crystal, and the calculated value of the heat generated is substituted into the energy equation. The electromagnetic wave's energy losses induced by its multiple refractions and reflections along with the resulting physical property changes of the lithium niobate crystal are considered. Influences of ambient temperature and heat transfer coefficient on refraction and walk-off angles of O-ray and E-ray in the cases of different incident powers and crystal thicknesses are analyzed. The E-ray electrical modulation instances, in which the polarized light waveform is adjusted to the rated condition via an applied electrical field in the cases of different ambient temperatures and heat transfer coefficients, are provided to conclude that there is a correlation between ambient temperature and applied electrical field intensity and a correlation between surface heat transfer coefficient and applied electrical field intensity. The applicable electrical modulation ranges without crystal breakdown are proposed. The study shows that the electrical field-adjustable heat transfer coefficient range becomes narrow as the incident power decreases and wide as the crystal thickness increases. In addition, it is pointed out that controlling the ambient temperature is easier than controlling the heat transfer coefficient. The results of the present study can be used as a quantitative theoretical basis for removing the adverse effects induced by thermal deposition due to linear laser absorption in the crystal, such as depolarization or wave front distortion, and indicate the feasibility of adjusting the refractive index in the window area by changing the heat transfer boundary conditions in a wide-spectrum laser.
Crossover between electromagnetically induced transparency and Autler-Townes splitting with dispersion
Based on Akaike's information criterion (AIC) for a coherently driven ensemble of cold rubidium atoms, we study the crossover between electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting from the dispersion as well as the absorption viewpoint. We find that the dispersion signal is more sensitive than the absorption signal, showing more pronounced features in the Akaike per-point weights spectrum, which provides a cleaner way of discerning EIT from AT splitting.
Vacuum induced transparency and slow light phenomena ina two-level atomic ensemble controlled by a cavity
Determination of the atomic density of rubidium-87
Comparison of absorption–dispersion and optical bistability behaviors between open and closed four-level tripod atomic systems
An equivalent circuit model for terahertz quantumcascade lasers: Modeling and experiments
Terahertz quantum cascade lasers (THz QCLs) emitted at 4.4 THz are fabricated and characterized. An equivalent circuit model is established based on the five-level rate equations to describe their characteristics. In order to illustrate the capability of the model, the steady and dynamic performances of the fabricated THz QCLs are simulated by the model. Compared to the sophisticated numerical methods, the presented model has advantages of fast calculation and good compatibility with circuit simulation for system-level designs and optimizations. The validity of the model is verified by the experimental and numerical results.
Effect of stimulated Brillouin scattering on the gain saturation of distributed fiber Raman amplifier and its suppression by phase modulation
Small-scale self-focusing of 200 ps laser pulses in Brillouin amplification
Comprehensive wind correction for a Rayleigh Doppler lidar from atmospheric temperature and pressure influences and Mie contamination
Design and optimization of a SiC thermal emitter/absorber composed of periodic microstructures based on a non-linear method
Spectral and directional control of thermal emission based on excitation of confined electromagnetic resonant modes paves a viable way for the design and construction of microscale thermal emitters/absorbers. In this paper, we present numerical simulation results of the thermal radiative properties of a silicon carbide (SiC) thermal emitter/absorber composed of periodic microstructures. We illustrate different electromagnetic resonant modes which can be excited with the structure, such as surface phonon polaritons, magnetic polaritons and photonic crystal modes, and the process of radiation spectrum optimization based on a non-linear optimization algorithm. We show that the spectral and directional control of thermal emission/absorption can be efficiently achieved by adjusting the geometrical parameters of the structure. Moreover, the optimized spectrum is insensitive to 3% dimension modification.
Realizing mode conversion and optical diode effect by coupling photonic crystal waveguides with cavity
X-ray communication based simultaneous communication and ranging
Spectroscopic properties of heavily Ho3+-doped barium yttrium fluoride crystals
The 30 at.% Ho: BaY2F8 crystals were grown by the Czochralski method, and their spectroscopic properties are analyzed systematically by standard Judd-Ofelt theory. The Judd-Ofelt intensity parameters are estimated to be Ω2=6.74× 10-20cm2, Ω4=1.20× 10-20 cm2, and Ω6=0.66× 10-20cm2, and the fluorescence branching ratios and radiative lifetimes for a series of excited state manifolds are also determined. The emission cross sections with our measured infrared luminescence spectra, especially important for 4.1 μm, are calculated to be about 4.37× 10-21 cm2. The crystal quality is preliminarily tested through a mid-infrared laser emission experiment.
Microflow-induced shear stress on biomaterial wall by ultrasound-induced encapsulated microbubble oscillation
Mechanical properties of GaxIn1-xAsyP1-y/GaAs systemat different temperatures and pressures
Laser-driven flier impact experiments at the SG-III prototype laser facility
Combustion of a single magnesium particle in water vapor
Plural interactions of space charge wave harmonics during the development of two-stream instability
We construct a cubically nonlinear theory of plural interactions between harmonics of the growing space charge wave (SCW) during the development of the two-stream instability. It is shown that the SCW with a wide frequency spectrum is formed when the frequency of the first SCW harmonic is much lower than the critical frequency of the two-stream instability. Such SCW has part of the spectrum in which higher harmonics have higher amplitudes. We analyze the dynamics of the plural harmonic interactions of the growing SCW and define the saturation harmonic levels. We find the mechanisms of forming the multiharmonic SCW for the waves with frequencies lower than the critical frequency and for the waves with frequencies that exceed the critical frequency.
Radial magnetic field in magnetic confinement device
Fluid simulation of inductively coupled Ar/O2 plasmas: Comparisons with experiment
In this work, a two-dimensional fluid model has been employed to study the characteristics of Ar/O2 radio frequency (RF) inductively coupled plasma discharges. The emphasis of this work has been put on the influence of the external parameters (i.e., the RF power, the pressure, and the Ar/O2 gas ratio) on the plasma properties. The numerical results show that the RF power has a significant influence on the amplitude of the plasma density rather than on the spatial distribution. However, the pressure and the Ar/O2 gas ratio affect not only the amplitude of the plasma density, but also the spatial uniformity. Finally, the comparison between the simulation results and the experimental data has been made at different gas pressures and oxygen contents, and a good agreement has been achieved.
Anomalous phase transition of InN nanowires under high pressure
Atomistic simulation of topaz: Structure, defect, and vibrational properties
In-situ wafer bowing measurements of GaN grown on Si (111) substrate by reflectivity mapping in metal organic chemical vapor deposition system
In this work, the wafer bowing during growth can be in-situ measured by a reflectivity mapping method in the 3× 2" Thomas Swan close coupled showerhead metal organic chemical vapor deposition (MOCVD) system. The reflectivity mapping method is usually used to measure the film thickness and growth rate. The wafer bowing caused by stresses (tensile and compressive) during the epitaxial growth leads to a temperature variation at different positions on the wafer, and the lower growth temperature leads to a faster growth rate and vice versa. Therefore, the wafer bowing can be measured by analyzing the discrepancy of growth rates at different positions on the wafer. Furthermore, the wafer bowings were confirmed by the ex-situ wafer bowing measurement. High-resistivity and low-resistivity Si substrates were used for epitaxial growth. In comparison with low-resistivity Si substrate, GaN grown on high-resistivity substrate shows a larger wafer bowing caused by the highly compressive stress introduced by compositionally graded AlGaN buffer layer. This transition of wafer bowing can be clearly in-situ measured by using the reflectivity mapping method.
Elastic properties and electronic structures of lanthanide hexaborides
Effects of tilt interface boundary on mechanical properties of Cu/Ni nanoscale metallic multilayer composites
ReaxFF molecular dynamics study on oxidationbehavior of 3C-SiC: Polar face effects
The oxidation of nanoscale 3C-SiC involving four polar faces (C(100), Si(100), C(111), and Si(111)) is studied by means of a reactive force field molecular dynamics (ReaxFF MD) simulation. It is shown that the consistency of 3C-SiC structure is broken over 2000 K and the low-density carbon chains are formed within SiC slab. By analyzing the oxygen concentration and fitting to rate theory, activation barriers for C(100), Si(100), C(111), and Si(111) are found to be 30.1, 35.6, 29.9, and 33.4 kJ·mol-1. These results reflect lower oxidative stability of C-terminated face, especially along  direction. Compared with hexagonal polytypes of SiC, cubic phase may be more energy-favorable to be oxidized under high temperature, indicating polytype effect on SiC oxidation behavior.
Viscosities and their correlations with structures of Cu-Ag melts
Gas adsorption and accumulation on hydrophobic surfaces: Molecular dynamics simulations
Growth condition optimization and mobility enhancement throughprolonging the GaN nuclei coalescence process ofAlGaN/AlN/GaN structure
Performance improvement in polymeric thin film transistors using chemically modified both silver bottom contacts and dielectric surfaces
Influence of a deep-level-defect band formed in a heavily Mg-doped GaN contact layer on the Ni/Au contact to p-GaN
Transient liquid assisted nucleation mechanism of YBa2Cu3O7-δ in coated conductor films derived by BaF2 process
Interface effect on structural and electronic properties of graphdiyne adsorbed on SiO2 and h-BN substrates: A first-principles study
We use the first-principles calculation method to study the interface effect on the structure and electronic properties of graphdiyne adsorbed on the conventional substrates of rough SiO2 and flat h-BN. For the SiO2 substrate, we consider all possible surface terminations, including Si termination with dangling bond, Si terminations with full and partial hydrogenation, and oxygen terminations with dimerization and hydrogenation. We find that graphdiyne can maintain a flat geometry when absorbed on both h-BN and SiO2 substrates except for the Si termination with partial hydrogenation (Si-H) SiO2 substrate. A lack of surface corrugation in graphdiyne on the substrates, which may help maintain its electronic band character, is due to the weak Van der Waals interaction between graphdiyne and the substrate. Si-H SiO2 should be avoided in applications since a covalent type bonding between graphdiyne and SiO2 will totally vary the band structure of graphdiyne. Interestingly, the oxygen termination with dimerization SiO2 substrate has spontaneous p-type doping on graphdiyne via interlayer charge transfer even in the absence of extrinsic impurities in the substrate. Our result may provide a stimulus for future experiments to unveil its potential in electronic device applications.
Defect stability in thorium monocarbide: An ab initio study
Investigation of optoelectronic properties of pure and Co substituted α-Al2O3 by Hubbard and modified Becke-Johnson exchange potentials
Electronic structures and elastic properties of monolayer and bilayer transition metal dichalcogenides MX2 (M= Mo, W; X= O, S, Se, Te): A comparative first-principles study
Coexistence of positive and negative magnetic entropy changes in CeMn2(Si1-xGex)2 compounds
Effects of electron-optical phonon interactions on the polaronenergy in a wurtzite ZnO/MxZn1-xO quantum well
Cubic ZnO films obtained at low pressure by molecular beam epitaxy
Effect of CuPc and MoO3 co-evaporated layer on the conductivity of organic light emitting diodes
Enhanced performances of AlGaInP-based light-emitting diodes with Schottky current blocking layers
Landau level transitions in InAs/AlSb/GaSb quantum wells
Magnetization dynamics of mixed Co-Au chains on Cu(110) substrate: Combined ab initio and kinetic Monte Carlo study
Influence of dry-etching damage on the electrical properties of an AlGaN/GaN Schottky barrier diode with recessed anode
Recovery of PMOSFET NBTI under different conditions
Vibration and buckling analyses of nanobeamsembedded in an elastic medium
Strongly enhanced flux pinning in the YBa2Cu3O7-X films with the co-doping of BaTiO3 nanorod and Y2O3 nanoparticles at 65 K
Growth and characterization of CaCu3Ru4O12 single crystal
High-quality single crystals of A-site ordered perovskite oxides CaCu3Ru4O12 were synthesized by flux method with CuO serving as a flux. The typical size of these single crystals was around 1× 1× 1 mm3 and the lattice constant was determined to be 7.430± 0.0009 Å by using x-ray single crystal diffraction. The surfaces of the samples were identified to be (100) surface. The high quality of the single crystal samples was confirmed by the rocking curve data which have a full width at half maximum of approximately 0.02 degree. The x-ray photoelectron spectroscopy measurement was performed and the temperature-dependent specific heat, magnetic susceptibility, and electric resistivity were measured along the  direction of the single crystals. All these measurements showed that the physical properties of CaCu3Ru4O12 single crystals are similar to that of polycrystals. However, the single crystals have a lower Curie susceptibility tail and a smaller residual resistivity than polycrystals, which indicates that the amount of paramagnetic impurities can be controlled by tuning the number of defects in CaCu3Ru4O12 samples.
Magnetic properties and magnetocaloric effects in Er1-xGdxCoAl intermetallic compounds
Shape-manipulated spin-wave eigenmodes of magnetic nanoelements
Room-temperature ferromagnetism induced by Cu vacancies in Cux(Cu2O)1-x granular films
Influence of RE-rich phase distribution in initial alloy on anisotropy of HDDR powders
Nonmonotonic effects of perpendicular magnetic anisotropy on current-driven vortex wall motions in magnetic nanostripes
High-energy pulse generation using Yb-doped Q-switched fiber laser based on single-walled carbon nanotubes
Photocarrier radiometry for noncontact evaluation of space monocrystalline silicon solar cell under low-energy electron irradiation
Improved thermoelectric property of cation-substituted CaMnO3
High-efficiency wideband flat focusing reflector mediated by metasurfaces
Raman scattering study of phase transition in Lu2O3-Ta2O5
Catalytic reduction of N2O by CO over PtlAum- clusters:A first-principles study
Improvement in bias current redistribution in superconducting strip ion detectors with parallel configuration
High-power TM01 millimeter wave pulse sensor in circular waveguide
Bending energy of a vesicle to which a small spherical particle adhere: An analytical study
Adaptive Kalman filter based state of charge estimation algorithm for lithium-ion battery
A new traffic model with a lane-changing viscosity term
Synchronization of Markovian jumping complex networks with event-triggered control
Global forward-predicting dynamic routing for traffic concurrency space stereo multi-layer scale-free network