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Unprecedented mismatch occur frequently in the photovoltaic (PV) array systems, challenging the classical monitoring systems. However, the study of artificial intelligence methods lacks some well-designed experiments for a systematic verification because mismatch are influenced by many aspects such as the PV array, the DC–DC converter, the DC–AC inverter, the loads as well as the environmental variables. The objective has two folds. One is to design some identical apparatuses to emulate the ‘same’ real-world solar power station that is operated under multiple mismatch for a controllable, repeatable and comparable experimental study. Another is to propose a novel condition monitoring strategy based on the backward propagation neural network and a decision-making formula. Some controllable indoor experiments and uncontrollable outdoor experiments are carried out to verify the ideas. Such work has never been studied before. The experimental results show that the derived monitoring systems identify and classify accurately different mismatch in both indoor tests and outdoor experiments. Moreover, real-time experimental results infer that the data-driven approach with the self-learning capabilities is adaptive to the environmental changes. Therefore, the supervised learning-based condition monitoring strategy is promising in the solar power industry in terms of operation management and performance enhancement.

Streptococcus pneumoniae is the most common pathogenic bacterium of pneumonia and can cause death. Here, we examined the impact of Baicalein on mouse mortality caused by Streptococcus pneumoniae infection. Baicalein protected mice from Streptococcus pneumoniae-induced deaths. Baicalein reduced alveolocapillary membrane permeability, lung infiltration of inflammatory cells, inflammatory cytokine production and pulmonary cell apoptosis. These evidences show that Baicalein is useful in the therapy of a severe form of pneumonia that can cause deaths.

Sperm activity is one of the important factors affecting male reproductive capacity. Computer assisted semen analysis (CASA) has a high clinical value for judging sperm motility. In this paper, sperm-related motion parameters were obtained by image preprocessing, dynamic and static target segmentation, minimum neighborhood matching sperm motions. In addition, a complete sperm trajectory detection software has been designed by using OpenCV (Open Source Computer Vision Library) to display sperm motions intuitively and generate relevant parameters automatically. The system has important reference value for sperm activity evaluation automation.

Photonics crystal(PhC)is the material in which the refractive index changes periodically and the PhC has a band structure and location mode,this structure can control light.In order to study two-dimensional PhC complete band gap,in this paper,plane wave expansion method was employed to simulate four types of two-dimensional PhC.We study the relationship between the complete bandgap and the variation of column radius r with a fixed lattice constant.We found that hexagonal lattice PhC air holes complete band gap appears in the r=0.42～0.50 μm range,complete band gap width does not increase with the air column radiu r,but there is a maximum width.The maximum band gap width is Δω1=0.08(ωa/2πc).When air column radiu r=0.47～0.50 μm,square lattice PhC exists complete bandgap,the band gap width Δω2=0.02(ωa/2πc).And complete band gap center frequency increases with r.Results indicate that for hexagonal and square GaAs columnar PhC there is no complete band gap.

The influence of external optical feedback (OFB) on the light-current characteristics of the vertical-cavity surface-emitting lasers (VCSELs) was investigated theoretically and experimentally. By calculating the OFB sensitivity parameter, the OFB sensibility of the VCSELs was compared with the edge emitting lasers. Based on the compound cavity theory, the light-current characteristic parameters of the VCSELs with external OFB, such as the threshold current and the slope efficiency, were calculated. The experimental results indicated that the threshold current of the VCSELs with different DBR reflectivities decreased to different degrees, accompanied with a decrease of slope efficiency when under 10% feedback ratio of the external OFB, which is in good agreement with the theoretical calculation.

A 980 nm bottom-emitting vertical-cavity surface-emitting laser linear array with high power density and a good beam property of Gaussian far-field distribution is reported. This array is composed of five linearly arranged elements with a 200 μm diameter one at the center, the other two 150 μm and 100 μm diameter ones at both sides of the center with center to center spacing of 300 μm and 250 μm, respectively. A power of 880 mW at a current of 4 A and a corresponding power density of up to 1 kW/cm2 is obtained. The temperature dependent characteristics of the linear array are investigated. The thermal interaction between the individual elements of the VCSEL linear array is smaller due to its optimized element size and device spacing, which make it more suitable for high power applications. A peak power of over 20 W has been achieved in pulsed operation with a 60 ns pulse length and a repetition frequency of 1 kHz.