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In complex underground conditions, the excavation of deep foundation pits has a significant impact on the deformation of retaining structures and nearby subway stations. To investigate the influence of deep excavation on the deformation of adjacent structures, a three-dimensional numerical model of the foundation pit, existing subway station, and tunnel structure was established using FLAC 3D software, based on the Shenzhen Bay Super Headquarters C Tower foundation pit project. The study analyzed the deformation characteristics of retaining structures, adjacent subway stations, and tunnels during different stages of deep excavation, and the accuracy of the numerical simulation results was validated through field monitoring data. The results indicate that during the excavation process of the foundation pit, the lateral horizontal displacement of the retaining structure is generally small, with a typical "concave inward" lateral deformation curve; the horizontal displacement value of the contiguous wall section is less than that of the interlocking pile section. The bending moments of the retaining structure show a distribution pattern with larger values in the middle and smaller values at the top and bottom of the pit, with a relatively uniform distribution of internal support forces. The maximum displacement of the nearby subway station is 8.75 mm, and the maximum displacement of the subway tunnel is 2.29 mm. The research findings can provide references for evaluating the impact of newly built foundation pits near subway stations and contribute to the rational design and safe construction of new projects. [ABSTRACT FROM AUTHOR]

The regulation of Fe2+ in yttrium iron garnet is a crucial factor in determining its dielectric and magnetic properties. This study successfully prepared Y3Mn0.2Fe4.8O12 ceramics, and studied their microstructure, magnetism, dielectric properties, and ferromagnetic linewidth through Mnn+ ion doping. The microstructural analysis revealed that the doping of low-valence Mn led to an increase in the grain size and density of ceramics, while the Mn4+–YIG showed the emergence of the second phase of YFeO3. Chemical composition analysis confirmed that the Fe2+ content was regulated by the Mn valence and that the lowest value was observed in Mn2+–YIG. The hysteresis loop demonstrated that the saturation magnetization decreased with the increase of Mn valence. In addition, low-valence Mn doping also reduced the dielectric loss and ferromagnetic resonance linewidth. Therefore, this study confirmed that low-valence metal doping could be a promising approach for regulating the Fe2+ content in YIG. [ABSTRACT FROM AUTHOR]

The parameters of a harmonic source change with the fluctuating background voltage and current in electric power system, which makes it difficult to establish accurate harmonic models. To solve this problem, a dynamic parameter model (DPM) for harmonic source networks is proposed in this paper. By equating the parameters of a harmonic source as a polynomial of voltage and current, the proposed model can adjust parameters accordingly. The model is not only suitable for a single harmonic source but also for complex harmonic source networks. The process of modeling need no internal information of the harmonic source. The performance of the model is, for different configurations of the harmonic source, compared to the performance of other harmonic models. The results show that the proposed model has higher accuracy and is more suitable for practical power system. [ABSTRACT FROM AUTHOR]

Abstract: Chin contour is an important facial feature to build a 3D morphable model, the core step of which is to establish feature points correspondence between each face in the training set and the reference face. In this paper, robust face detection is implemented firstly using probabilistic method. A probability of detection is obtained for each image of different position and at several scales and poses. Then, the chin contours are extracted accurately using the active shape model (ASM), which depends on the parameters obtained from the face detection. From frontal (0°) to profile (90°) faces that are equally divided into 10 parts, we train 10 flexible models. Then, different flexible models are used to extract the face chin contour according to the corresponding face pose. Experimental results show that the proposed approach can extract the chin contours of different people across different poses with good accuracy. [Copyright &y& Elsevier]

Abstract: This paper develops a novel framework that is capable of dealing with small sample size problem posed to subspace analysis methods for face representation and recognition. In the proposed framework, three aspects are presented. The first is the proposal of an iterative sampling technique. The second is adopting divide–conquer–merge strategy to incorporate the iterative sampling technique and subspace analysis method. The third is that the essence of 2D PCA is further explored. Experiments show that the proposed algorithm outperforms the traditional algorithms. [Copyright &y& Elsevier]