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The inner wall corrosion of pipelines is concealed and hard to monitor in time. In order to visualize the shape of the internally corroded pipeline, as well as the defect volume and its spatial distribution, a three-dimensional(3D) model reconstruction method based on the ultrasonic phased array technology was proposed for the internally corroded pipeline. A self-built acquisition platform was used to control the one-dimensional linear array probes for the phased array, and the reflected echo signal was used to obtain the space coordinates between the inner and outer diameters of the corroded pipeline. Then, the point cloud data set between the inner and outer diameters was constructed by the interpolation method, and the point cloud data of each fracture zone were obtained by the hierarchical scanning method. Besides,data processing, reverse model reconstruction and forward modeling were performed for the 3D model reconstruction of the collected point cloud data. Finally, the reconstructed 3D model was compared with the point cloud data obtained by the Creaform 3D laser scanner. The results show that it is feasible to obtain the point cloud data using one-dimensional linear array probes based on the ultrasonic phased array technology, and the established 3D model and defects have small errors and high precision, which has important reference value for the safety evaluation of oil and gas pipelines.

C19H17BrO3, triclinic, P 1‾ $\overline{1}$ (no. 2), a = 8.2887(7) Å, b = 8.4190(12) Å, c = 13.1164(15) Å, α = 93.634(11)°, β = 90.609(9)°, γ = 118.201(11)°, V = 804.17(18) Å3, Z = 2, R gt(F) = 0.0738, wR ref(F 2) = 0.1614, T = 150 K.

C18H15BrO2, monoclinic, P21/n (no. 14), a = 9.1704(9) Å, b = 16.5309(13) Å, c = 10.3528(12) Å, β = 112.368(12)°, V = 1451.3(3) Å3, Z = 4, R gt(F) = 0.0405, wR ref(F 2) = 0.0677, T = 149.99(10) K.

According to the "White Paper on China's Intelligent Internet of Things (AIoT) 2020",with the prompt development of China's 5G network,the rapid popularization of large-capacity with low-price IoT sensor devices and the explosive growth of data,image processing is widely used in various fields of Internet of Things,such as smart city,smart transportation,smart healthcare,and other industry,etc.In these research areas,researchers usually ignore the actual problems in the data collection process,for instance,data degradation caused by time changes:seasonal shifting,diurnal variation,weather changes,and noise problems caused by spatial changes:object superposition,blur,and partial occlusion.Among those problems,the weather pro-blems represented by rainy days are the most challenging and common.Therefore,this paper systematically investigates the actual problems in the data collection process above,classifies and summarizes the image rain-removal algorithms under complex weather conditions.At the same time,regarding the compute-intensive execution of such algorithms,we utilize the Amazon EC2 cloud instance G4 and P3 series to quantitatively evaluate the processing time and effect of various reviewed rain removal algorithms.Finally,we illustrate the characteristics of various rain removal algorithms and the latest trends in Cloud-IoT applications.

In this study, we conducted molecular dynamic simulations to investigate the thermal expansion behavior of Janus MoSSe nanotubes. We focused on understanding how the intrinsic strain in these nanotubes affects their thermal expansion coefficient (TEC). Interestingly, we found that Janus MoSSe nanotubes with sulfur (S) on the outer surface (MoSeS) exhibit a different intrinsic strain compared to those with selenium (Se) on the outer surface (MoSSe). In light of this observation, we explored the influence of this intrinsic strain on the TEC of the nanotubes. Our results revealed distinct trends for the TEC along the radial direction (TEC- r) and the axial direction (TEC- l x ) of the MoSSe and MoSeS nanotubes. The TEC- r of MoSeS nanotubes was found to be significantly greater than that of MoSSe nanotubes. Moreover, the TEC- l x of MoSeS nanotubes was smaller than that of MoSSe nanotubes. Further analysis showed that the TEC- r of MoSeS nanotubes decreased by up to 37% as the radius increased, while that of MoSSe nanotubes exhibited a slight increase with increasing radius. On the other hand, the TEC- l x of MoSeS nanotubes increased by as much as 45% with increasing radius, whereas that of MoSSe nanotubes decreased gradually. These opposite tendencies of the TECs with respect to the radius were attributed to the presence of intrinsic strain within the nanotubes. The intrinsic strain was found to play a crucial role in inducing thermally induced bending and elliptization of the nanotubes' cross-section. These effects are considered key mechanisms through which intrinsic strain influences the TEC. Overall, our study provides valuable insights into the thermal stability of Janus nanotubes. By understanding the relationship between intrinsic strain and the thermal expansion behavior of nanotubes, we contribute to the broader understanding of these materials and their potential applications. [ABSTRACT FROM AUTHOR]

In order to study on the vibration effect of the blasting in the upper and lower cross tunnels, depress the impact of blasting vibration on existing adjacent tunnel and acquire the sound way of tunnel blasting construction, the finite element software LS-DYNA was adopted to calculate what vibration effect of existing tunnel would be generated by the different detonation modes (simultaneous initiation and hole-by-hole initiation) and the different cut modes (parallel cut and oblique cut). In general, the results of numerical simulation compared with the results measured in real, they are generally consistent. Results show that the vibration velocity of hole-by-hole initiation of digital electronic detonator is 40% lower than ordinary simultaneous initiation of millisecond detonator, and the vibration acceleration is reduced by 24%. As regards vibration displacement, the distinction between the two detonation modes is small. The rule of velocity decay with increasing distance from the initiating position is similar in this two cases. Meanwhile, the vibration velocity of oblique cut is lower than parallel cut. But, for the vibration acceleration, the oblique cut is 15% higher than parallel cut. For oblique cut, the seismic waves show a pronounced periodicity and the energy is relatively concentrated. The fact is quite opposite when the parallel cut applied. In the case of explosion of hard rock strata, the effect of oblique cut is better than parallel cut.

Gastric cancer (GC) is a prominent global health issue, as it ranks as the fifth most prevalent type of cancer and the fourth most significant cause of cancer-related mortality worldwide. Although H. pylori is known to play a role in the development of GC, genetic factors also play a role in its onset and progression. Recent studies have shown that genetic polymorphisms are strongly associated with the development of GC and that certain single nucleotide polymorphisms (SNPs) can be used as biomarkers for early diagnosis and prevention. Epigenetic disturbances, such as DNA methylation, are involved in the development of GC, and mutations in the DNA methyltransferase (DNMT) gene have been found to increase the risk of GC. However, previous findings on the association between DNMTs SNPs and GC risk have been inconsistent. In this study, an updated meta-analysis of three well-studied and controversial DNMTs polymorphic loci, DNMT1 rs16999593, DNMT3A rs1550117 and DNMT3B rs1569686, was performed to provide more reliable results. It was found that DNMT1 rs16999593 was not associated with GC, DNMT3A rs1550117 may have a positive association with GC risk, and DNMT3B rs1569686 may be a protective factor for GC. These findings may provide valuable information for early diagnosis and prevention of GC, but further studies are needed to confirm these results. [ABSTRACT FROM AUTHOR]