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This paper first systematically reviews the research on shield and TBM construction ventilation technology in the tunnel (hole) and coal mine roadway engineering; then, it briefly introduces the general situation of the main and auxiliary inclined shaft project of Kekegai Coal Mine and makes a theoretical analysis on the ventilation design principle and ventilation mode selection of the project according to the general situation of the project. Based on the above analysis, a variety of designs and comparisons of construction ventilation schemes are carried out, and it is decided that the two-stage single head forced ventilation scheme with replacement fan is adopted for both inclined shafts; then the selected ventilation scheme is checked theoretically; finally, the ventilation effect is tested. The field practice shows that the ventilation effect is good.

C30H72N10O7S2, triclinic, P1̄ (no. 2), a = 8.75510(10) Å, b = 15.1170(2) Å, c = 16.8843(2) Å, α = 76.272(1)° $76.272(1){}^{\circ}$ , β = 78.397(1)° $78.397(1){}^{\circ}$ , γ = 88.277(1)° $88.277(1){}^{\circ}$ , V = 2126.09(5) Å3, Z = 2, R gt(F) = 0.0407, wR ref(F 2) = 0.1282, T = 296(2) K.

Alkali-free aluminoborosilicate glasses were prepared by the conventional melting method. The effect of the replacement of CaO by La₂O₃ on the structure, thermal, and dielectric properties of the glasses was investigated by FTIR, DSC, with thermal expansion instruments, and an impedance analyser. With increasing ratios of La₂O₃ to CaO, the densities of the glasses increased linearly from 2.458 to 2.627 g cm-3. Meanwhile, the polymerisation degree of the glass network increased first and then decreased. The glass transition temperature, crystallisation onset temperature and expansion softening temperature showed a gradually increasing trend, while the thermal stability firstly deteriorated, then gradually improved. Additionally, the coefficient of thermal expansion (CTE), dielectric constant and dielectric loss initially decreased, followed by an increase. The sample with the La₂O₃ ratio of 1.00 showed excellent properties: had a low CTE (2.71 × 10-6 °C-1), had a dielectric constant (5.23), and a dielectric loss (1.12 × 10-3), which means it is a promising material for integrated circuit packaging applications.

Objective To investigate the association between fetal hemoglobin (HbF) level in arterial blood early after birth and the onset of retinopathy of prematurity (ROP) in preterm infants with a gestational age of

Subsurface site characterization is essential for geotechnical engineering applications (e.g., slope stability analysis and deep excavation design), which is usually achieved through geotechnical site investigation and might be supplemented by geophysical survey. Geotechnical and geophysical investigations are complementary in many aspects. Geotechnical investigation provides direct measurement data with high accuracy but only at limited locations. On the other hand, geophysical survey provides abundant two-dimensional (2D) or three-dimensional measurements, but the data are often indirect. In addition, geotechnical and geophysical data are usually correlated. Therefore, fusion of geotechnical and geophysical data during site characterization is beneficial. This paper proposed a novel data fusion method, called multi-source Bayesian compressive sampling, for fusion of geotechnical and geophysical data and statistical characterization of 2D subsurface profiles. The proposed method is data-driven and non-parametric, without the need for an empirical parametric function between geotechnical and geophysical data. The proposed method was illustrated and validated using both numerical and real-life examples. The results show that the proposed method not only properly characterizes 2D subsurface profiles but also explicitly quantifies the statistical uncertainty associated with the site characterization. Key words: site characterization, data fusion, geotechnical data, geophysical data, Bayesian method, compressive sensing La caracterisation de la subsurface d'un site est essentielle pour les applications de l'ingenierie geotechnique (par exemple, l'analyse de la stabilite des pentes, la conception des excavations profondes), ce qui est generalement realise par une etude geotechnique du site et peut etre complete par une etude geophysique. Les etudes geotechniques et geophysiques sont complementaires a bien des egards. L'etude geotechnique fournit des donnees de mesure directe avec une grande precision, mais seulement a des endroits limites. D'autre part, les leves geophysiques fournissent d'abondantes mesures bidimensionnelles (2D) ou tridimensionnelles, mais les donnees sont souvent indirectes. En outre, les donnees geotechniques et geophysiques sont generalement correlees. Il est donc avantageux de fusionner les donnees geotechniques et geophysiques pendant la caracterisation du site. Cet article propose une nouvelle methode de fusion de donnees, appelee echantillonnage bayesien compressif multi-sources, pour la fusion de donnees geotechniques et geophysiques et la caracterisation statistique de profils de subsurface en 2D. La methode proposee est axee sur les donnees et non parametrique, sans avoir besoin d'une fonction parametrique empirique entre les donnees geotechniques et geophysiques. La methode proposee a ete illustree et validee a l'aide d'exemples numeriques et reels. Les resultats montrent que la methode proposee permet non seulement de caracteriser correctement les profils de subsurface en 2D, mais aussi de quantifier explicitement l'incertitude statistique associee a la caracterisation du site. [Traduit par la Redaction] Mots-cles : caracterisation du site, fusion de donnees, donnees geotechniques, donnees geophysiques, methode bayesienne, detection par compression, 1. Introduction Site characterization is essential for geotechnical engineering designs and analysis (e.g., slope stability analysis and deep excavation design), which is usually achieved by geotechnical site investigation and might [...]

Aiming at the problems of short standby time and limited beam coverage in collaborative communication of UAVs, a collaborative beamforming method of UAV based on genetic algorithm is proposed. Based on the random antenna array theory, this method establishes the UAV collaborative beamforming system model, takes the minimum sidelobe level as the optimization goal, and obtains the optimal beam pattern by using genetic algorithm (GA) combined with the selection of optimal node position and optimal beamforming coefficient respectively. The performance comparison of beam pattern with phase error among nodes is analyzed. The simulation results show that the proposed method can effectively improve the beam gain in the target direction, can reduce the peak sidelobe level of the beam pattern, and improve the communication capacity. Among them, the genetic algorithm based on coefficient optimization can reduce the transmission power of each UAV node, save the energy consumption of UAV, and greatly increase the working time of UAV.