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The dependence of the black hole (BH) shadow and thermodynamics may be structured in the regular spacetime. Taking the regular Bardeen-AdS BH as an example, the relationship between the shadow radius and the event horizon radius is derived. It is found that these two radii display a positive correlation, implying that the BH temperature can be rewritten as a function of shadow radius in the regular spacetime. By analyzing the phase transition curves under the shadow context, we found that the shadow radius can replace the event horizon radius to present the BH phase transition process, and the phase transition grade can also be revealed by the shadow radius, indicating that the shadow radius may serve as a probe for the phase structure in the regular spacetime. Utilizing the temperature-shadow radius function, the thermal profile of the Bardeen-AdS BH is established. We obtained that the temperature shows an N-type change trend in P, Comment: 12 pages, 6 figures

To overcome the shortcomings of UV-Vis spectrometry and fluorescence spectrometry for COD detection, an online measurement named FfCODnet has been proposed and estimated in this paper. In this method, UV-Vis spectrum and fluorescence emission spectrum are collected online by a spectrophotometer, then De-noising Auto-Encoders (part of FfCODnet, abbreviated as DAE) are used to clean two types of raw spectrum respectively, finally the rest of FfCODnet is utilized to predict COD value of water sample. Through experiments and results comparison, the result shows that the proposed method has a good performance on both noise tolerance and measure accuracy.

The evaluation of rock phase and reservoir property is the key problem to be solved in the exploration of deep sand conglomerate. The study of rock phase information is only in the qualitative stage according to the FMI logging data with the results are mainly image-lithologic models. It is urgent to extract gravel information based on image analysis. FMI image can be transformed into a vertical core gravel image after the operation of grayscale, blind area filling, image filtering, image segmentation and gravel extraction. The maximum gravel size is selected as the rock phase marker, and the statistical relationship of the conventional logging curves with resistivity, GR and density is established. It can provide a useful supplement for petrographic classification.

Outokumpu has developed a new duplex stainless steel with improved formability compared to other duplex grades. The so-called Forta FDX grades allows the utilization of duplex grades in more forming intensive products previously not possible and at the same time benefit from other duplex stainless steel properties for increased application performance. In this paper a Gasket Plate Heat Exchanger (GPHE) plate is formed with the new duplex grade Forta FDX 27 and compared to the baseline grade Supra 316L/4404. Detailed material characterization, strain measurements and Finite Element Analysis (FEA) were performed to further investigate the case. Small differences in measured strain distribution between Forta FDX 27 and Supra 316L/4404 were found after the stamping operation for both material grades and for the same design feature. Strain measurements showed reasonable agreement between measured experimental results and the numerical simulation for Forta FDX 27. Additionally, FEA predicts an improvement of the final strength of the product up to 30 % at the final configuration by using Forta FDX 27 instead of Supra 316L/4404.

With the increasing share of the wind power in the power system, wind power fluctuations will cause obvious negative impacts on weak local grid. This paper firstly establish electromechanical transient simulation model for doubly fed induction wind turbine, then use Matlab/Simulink to achieve power flow calculation and transient simulation of power system including wind farms, the local synchronous generator, load, etc, finally analyze wind power on the impact of the local power grid under typical circumstances. The actual calculated results indicate that wind mutation causes little effect on the power grid, but when the three-phase short circuit fault happens, active power of wind power decreases sharply and the voltage of location of wind power into the grid also drop sharply, finally wind farm split from power system. This situation is not conducive to security and stability of the local power grid. It is necessary to develop security and stability measures in the future.