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Chinese Journal of Aeronautics 2021年第5期34卷 466-484页

作者： Mengyao BAO Shuiting DING Guo LI Civil Aviation Management Institute of China Beijing 100102China Aircraft|Engine Integrated System Safety Beijing Key Laboratory Beihang UniversityBeijing 100083China

Turbocharging is an efficient approach for addressing power reduction and oil consumption increase in aviation piston engines during high-altitude ***,a turbocharger significantly increases the complexity of a power system,and its considerably complex matching relation with the engine results in a coupling of failure *** analytical methods are hard to identify failure-inducing ***,safety issues are becoming increasingly *** study focuses on methods for identifying failure-inducing factors.A whole-machine system model is established and validated through *** response surface method is employed to further abstract the system simulation model to a surrogate model(average error:~3%)in order to reduce the computational cost while ensuring *** this basis,an improved Correspondence Analysis(CA)-polar angle(PA)-based Classification(PAC)is proposed to identify the key factors affecting the failure mode of *** identification method is based on the row profile coordinates G varying with the numerical deviations of the key factors,and is capable of effectively identifying the key factors affecting the *** a validation example,this method identifies the diameter of the exhaust valve(e_(2))as the primary factor affecting the safety margin for each work boundary.

关键词： Failure-inducing factors Improved correspondence analysis polar angle Turbochargers Whole-machine system model

Effect of variations in the polar and azimuthal angles of coarse particles on the structure of drainage channels in thickened beds

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International Journal of Minerals,Metallurgy and Materials 2023年第12期30卷 2321-2333页

作者： Cuiping Li Gezhong Chen Zhu’en Ruan Raimund Bürger Yuan Gao Hezi Hou Hui Wang Key Laboratory of the Ministry of Education of China for High-efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China CI2MA and Departamento de Ingeniería Matemática Facultad de Ciencias Físicas y MatematicasUniversidad de ConcepcionCasilla 160-CConcepciónChile School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

The 3D reconstruction and quantitative characterization of drainage channels and coarse tailings particles in a bed were conducted in this *** influence of variations in the azimuthal angle(θ)and polar angle(φ)of coarse particles on drainage channel structure was analyzed,and the drainage mechanism of the bed was *** showed that water discharge in the bed reduced the size of pores and throat channels,increasing slurry *** throat channel structure was a key component of the drainage ***φandθof particles changed predominantly along the length *** changes inφhad a cumulative plugging effect on the drainage channel and increased the difficulty of water *** rake and rod formed a shear ring in the tailings bed with shear,and theθdistribution of particles changed from disorderly to orderly during the rotation *** drainage channel was squeezed during the shearing process with the change inθ,which broke the channel structure,encouraged water discharge in the bed,and facilitated a further increase in slurry *** findings of this work are expected to offer theoretical guidance for preparing high-concentration underflow in the tailings thickening process.

关键词： tailings thickening coarse particle azimuthal angle polar angle drainage channels

Reflection for three-dimensional plane waves in triclinic crystalline medium

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Applied Mathematics and Mechanics(English Edition) 2007年第10期28卷 1309-1318页

作者： Amares Chattopadhyay Department of Applied Mathematics Indian School of Mines UniversityDhanbad-826004JharkhandIndia

The propagation of three-dimensional plane waves at a traction free boundary of a half-space composed of triclinic crystalline material is discussed. A method has been developed to find the analytical expressions of all the three phase velocities of quasi-P （qP）, quasi-SV （qSV） and quasi-SH （qSH） in three dimensions. Closed form expressions in three dimensions for the amplitude ratios of reflection coefficients of qP, qSV and qSH waves in a triclinic medium are obtained. These expressions are used for numerically studying the variation of the reflection coetticients with the angle of incidence. The graphs are drawn for different polar angle and azimuth. Numerical results presented indicate that the anisotropy affect the reflection coetticients significantly in the three dimensional case compared to the two-dimensional case.

关键词： three-dimensional polar angle azimuth reflection triclinic medium quasi-P quasi-SV quasi-SH waves

Orientation determination of nitrogen-vacancy center in diamond using a static magnetic field

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Chinese Physics B 2023年第7期32卷 249-253页

作者：王杨鹏章如健杨燕吴琴于志飞陈冰 Department of Physics Hefei University of TechnologyHefei 230009China

Nitrogen-vacancy(NV)centers in a bulk diamond are often employed to realize measurement of multiple physical quantities,which depends on orientation information of NV *** report a fast and effective method to determine the orientation of NV axis with the aid of a static magnetic *** measuring the optically detected magnetic resonance spectra,we can precisely extract the polar angle information between the NV axis and the known magnetic *** with the polar angle information of different kinds of NV centers,we employ the Nelder-Mead algorithm to get the optimal solution of the orientation of NV *** method is simple and efficient,and is easily applied in NV-based quantum sensing.

关键词： nitrogen-vacancy centers polar angle quantum sensing