By establishing the numerical model in the vertical plane and the similar model in the horizontal plane of gas flow in goaf, the influence of high drainage roadway or drilling on the gas seepage field was analyzed, an...By establishing the numerical model in the vertical plane and the similar model in the horizontal plane of gas flow in goaf, the influence of high drainage roadway or drilling on the gas seepage field was analyzed, and the extraction mechanism was clarified. On this basis, the academic thought of directional long drilling group instead of high drainage roadway was put forward. And then using complex function theory, the permeation mechanical model of drilling group with circle distribution in the mining-induced fracture zone was established to explore the coupling relationship between the drilling quantity, extraction volume and the equivalent extraction rate of single drilling. Finally, combined with the concrete geological production conditions, the main parameters of directional long drilling group were determined. The distance between the drilling group center and the air-return roadway is 24 m, the height is 18 m, and the three drillings are in an approximate equilateral triangle distribution with a space of 8 m. The equivalent extraction square is 4.15 m2. It is shown that the effect of directional long drilling group is evident. The gas content in the upper comer is controlled below 0.95%, the content in the tail roadway is kept below the alarm value, and the content is over 50% in the drill, realizing the secure and effective extraction of coal and gas.展开更多
行人重识别虽已取得了显著进展,但在实际应用场景中,不同障碍物引起的遮挡问题仍然是一个亟待解决的挑战。为了从被遮挡行人中提取更有效的特征,提出了一种基于可学习掩模和位置编码(Learnable mask and position encoding, LMPE)的遮...行人重识别虽已取得了显著进展,但在实际应用场景中,不同障碍物引起的遮挡问题仍然是一个亟待解决的挑战。为了从被遮挡行人中提取更有效的特征,提出了一种基于可学习掩模和位置编码(Learnable mask and position encoding, LMPE)的遮挡行人重识别方法。首先,引入了一种可学习的双路注意力掩模生成器(Learnable dual attention mask generator, LDAMG),生成的掩模能够适应不同遮挡模式,显著提升了对被遮挡行人的识别准确性。该模块可以使网络更灵活,能更好地适应多样性的遮挡情况,有效克服了遮挡带来的困扰。同时,该网络通过掩模学习上下文信息,进一步增强了对行人所处场景的理解力。此外,为了解决Transformer位置信息损耗问题,引入了遮挡感知位置编码融合(Occlusion aware position encoding fusion, OAPEF)模块。该模块进行不同层次位置编码融合,使网络获得更强的表达能力。通过全方位整合图像位置编码,可以更准确地理解行人间的空间关系,提高模型对遮挡情况的适应能力。最后,仿真实验表明,本文提出的LMPE在Occluded-Duke和Occluded-ReID遮挡数据集以及Market-1501和DukeMTMC-ReID无遮挡数据集上都取得了较好的效果,验证了本文方法的有效性和优越性。展开更多
基金Project(50834005) supported by the National Natural Science Foundation of ChinaProject(2010QZ06) supported by the Fundamental Research Funds for the Central Universities of China
文摘By establishing the numerical model in the vertical plane and the similar model in the horizontal plane of gas flow in goaf, the influence of high drainage roadway or drilling on the gas seepage field was analyzed, and the extraction mechanism was clarified. On this basis, the academic thought of directional long drilling group instead of high drainage roadway was put forward. And then using complex function theory, the permeation mechanical model of drilling group with circle distribution in the mining-induced fracture zone was established to explore the coupling relationship between the drilling quantity, extraction volume and the equivalent extraction rate of single drilling. Finally, combined with the concrete geological production conditions, the main parameters of directional long drilling group were determined. The distance between the drilling group center and the air-return roadway is 24 m, the height is 18 m, and the three drillings are in an approximate equilateral triangle distribution with a space of 8 m. The equivalent extraction square is 4.15 m2. It is shown that the effect of directional long drilling group is evident. The gas content in the upper comer is controlled below 0.95%, the content in the tail roadway is kept below the alarm value, and the content is over 50% in the drill, realizing the secure and effective extraction of coal and gas.
