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High Dynamic Range (HDR) images are widely used in automotive, aerospace, AI, and other fields but are limited by the maximum dynamic range of a single data acquisition using CMOS image sensors. High dynamic range images are usually synthesized through multiple exposure techniques and image processing techniques. One of the most challenging task in multiframe Low Dynamic Range (LDR) images fusion for HDR is to eliminate ghosting artifacts caused by motion. In traditional algorithms, optical flow is generally used to align dynamic scenes before image fusion, which can achieve good results in cases of small-scale motion scenes but causes obvious ghosting artifacts when motion magnitude is large. Recently, attention mechanisms have been introduced during the alignment stage to enhance the network’s ability to remove ghosts. However, significant ghosting artifacts still occur in some scenarios with large-scale motion or oversaturated areas. We proposea novel Distilled Feature TransformerBlock (DFTB) structure to distill and re-extract information from deep image features obtained after U-Net downsampling, achieving ghost removal at the semantic level for HDR fusion. We introduce a Feature Distillation Transformer Block (FDTB), based on the Swin-Transformer and RFDB structure. FDTB uses multiple distillation connections to learn more discriminative feature representations. For the multiexposure moving scene image fusion HDR ghost removal task, in the previous method, the use of deep learning to remove the ghost effect in the composite image has been perfect, and it is almost difficult to observe the ghost residue of moving objects in the composite HDR image. The method in this paper focuses more on how to save the details of LDR image more completely after removing the ghost to synthesize high-quality HDR image. After using the proposed FDTB, the edge texture details of the synthesized HDR image are saved more perfectly, which shows that FDTB has a better effect in saving the details of image fusion. Futhermore, we propose a new depth framework based on DFTB for fusing and removing ghosts from deep image features, called TransU-Fusion. First of all, we use the encoder in U-Net to extract image features of different exposures and map them to different dimensional feature spaces. By utilizing the symmetry of the U-Net structure, we can ultimately output these feature images as original size HDR images. Then, we further fuse high-dimensional space features using Dilated Residual Dense Block (DRDB) to expand the receptive field, which is beneficial for repairing over-saturated regions. We use the transformer in DFTB to perform low-pass filtering on low-dimensional space features and interact with global information to remove ghosts. Finally, the processed features are merged and output as an HDR image without ghosting artifacts through the decoder. After testing on datasets and comparing with benchmark and state-of-the-art models, the results demonstrate our model’s excellent information fusion ability and stronger ghost removal capability.

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During extra-thick coal seam mining, the high-level thick and hard strata are the main reason for the presence of a strong ground pressure in the working face; however, there is no active and effective control technology for high-level hard strata. This paper proposes the concept of ground fracturing hard roofs, and the physical simulation was used to study the control effect of ground fracturing on the strata breaking structure and energy release. The results showed that the ground fracturing changed the structural characteristics of the strata and reduced the energy release intensity and overburden movement spatial extent, which had a significant control effect on the ground pressure. The Datong mining area was selected as the engineering background, a ground horizontal well fracturing engineering test was conducted on site, and a 20-m-thick hard rock layer, which was 110 m vertically away from the coal seam, was determined as the fracturing target layer. On-site microseismic monitoring showed that the crack propagation length was up to 216 m, and the height was up to 50 m. On-site mine pressure monitoring showed that the roadway deformation was reduced to 100 mm, the periodic weighting characteristics of the hydraulic supports were not obvious, the ground pressure in the working face was significantly controlled, and the ground fracturing was successful. Ground fracturing changed the occurrence characteristics of the high-level hard strata, which is beneficial to ameliorate the stress environment of a working face and provide a new approach of hard rock control.