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Wave resonance in the gaps formed by a four-float array for various drafts and incident wave frequencies is investigated using a numerical wave tank based on OpenFOAM. In the gap perpendicular to the direction of wave propagation, the resonant wave height is higher than that between two side-by-side floats under the same draft, and the resonant frequency is also different. Significant variations in wave height distribution are observed along the gap parallel to the wave propagation direction under different incident wave frequencies. When the incident wave frequencies are higher than the resonant frequency, the lateral force amplitude on the front floats increases, while the force amplitude on the rear floats does not show this effect. Using the dynamic mode decomposition method, we discover that the irregular distribution of wave heights across different frequencies leads to an increase in the lateral force amplitude on the front floats at non-resonant frequencies. [ABSTRACT FROM AUTHOR]

In this paper, In2O3 thin films were prepared on quartz glass substrate by sol-gel method using indium nitrate hydrate (In(NO3)3·xH2O) as precursor, ethylene glycol(C2H6O2) as solvent, and acetylacetone(C5H8O2) as catalyst. The effects of precursor In3+ concentration, annealing temperature, and annealing time on the properties of In2O3 thin films were experimentally investigated. With As the concentration of In3+ in the precursor solution increases, the diffraction peak of the (222) crystal plane becomes stronger and sharper, indicating that the preferred orientation of the In2O3 film along the (222) crystal plane is becoming stronger and the crystallinity is getting better. The average grain size increases, the lattice strain and dislocation density decrease, the roughness and film thickness increase, and the optical transmittance and optical band gap decrease. With the increase of annealing temperature and annealing time, the diffraction peak intensity of In2O3 film increases, the half-high width of the diffraction peak shrinks, the average grain size increases, the light transmittance increases, the crystal defects decrease, the crystal structure is more orderly, and the crystallinity of the film increases. At the same time, the optical band gap remains almost constant. [ABSTRACT FROM AUTHOR]

Al0.9Ga0.1As/GaAs distributed Bragg reflector (DBR) structure with different doping type and doping concentrations was grown by metal organic chemical vapor deposition (MOCVD), and the material and optoelectronic characteristics were studied by X-ray diffraction (XRD) rocking curves, scanning electron microscopy (SEM), electrochemical capacitance–voltage (ECV) profiling, and low-temperature photoluminescence spectroscopy. Results showed that period thickness of AlGaAs and GaAs layers was reduced by the CCl4 doping process and that the AlGaAs layer achieved a higher doping concentration than the GaAs materials. Additionally, there exist four recombination mechanisms in the structure of fabricated Al0.9Ga0.1As/GaAs DBR with varied doping. The recombination between the electrons of the conduction band and holes of the valence band in the 2.09 × 1018 cm−3 Si-doped GaAs layers dominated the photoluminescence in the lower temperature range, while recombination in the 1.08 × 1018 cm−3 C-doped GaAs layers gradually became the dominant factor at near room temperature. [ABSTRACT FROM AUTHOR]

This paper proposes a non-intrusive computational method for mechanical dynamic systems involving a large-scale of interval uncertain parameters, aiming to reduce the computational costs and improve accuracy in determining bounds of system response. The screening method is firstly used to reduce the scale of active uncertain parameters. The sequential high-order polynomials surrogate models are then used to approximate the dynamic system’s response at each time step. To reduce the sampling cost of constructing surrogate model, the interaction effect among uncertain parameters is gradually added to the surrogate model by sequentially incorporating samples from a candidate set, which is composed of vertices and inner grid points. Finally, the points that may produce the bounds of the system response at each time step are searched using the surrogate models. The optimization algorithm is used to locate extreme points, which contribute to determining the inner points producing system response bounds. Additionally, all vertices are also checked using the surrogate models. A vehicle nonlinear dynamic model with 72 uncertain parameters is presented to demonstrate the accuracy and efficiency of the proposed uncertain computational method. [ABSTRACT FROM AUTHOR]