3D finite element simulation of tunnel boring machine construction processes in deep water conveyance tunnel

Applying stiffness migration method, a 3D finite element mechanical model is established to simulate the excavation and advance processes. By using 3D nonlinear finite element method, the tunnel boring machine (TBM) excavation process is dynamically simulated to analyze the stress and strain field status of surrounding rock and segment. The maximum tensile stress of segment ring caused by tunnel construction mainly lies in arch bottom and presents zonal distribution. The stress increases slightly and limitedly in the course of excavation. The maxi-mum and minimum displacements of segment, manifesting as zonal distribution, distribute in arch bottom and vault respectively. The displacements slightly increase with the advance of TBM and gradually tend to stability.     

Fracture behavior characteristic of ceramic reinforced metal-base coatings

The fracture behavior of a ceramic reinforced metal-base coating prepared by high velocity arc spraying (HVAS)technology in three-point bending test was studied.Moreover,finite element analysis(FEA)was adopted to analyze the stress distribution in the crack front.It can be found that the crack norrnal to the interface in the coatings occurred at the location where a fixed moment of force was reached.So the critical moment can be taken as thecoating cracking criterion,which was confirmed by FEA results.In addition,the stress levels at three different locations where cracks occurred near the interface are almost the same.The results will provide reference for the design of coatings and the structure integrity evaluation of coating/substrate systems.     

红色基因元素代入式专业课程思政体系建设探索

为落实高校"立德树人"的根本任务,担负好为党育人,为国育才的使命,在高校积极推进课程思政建设.本文以软件工程专业为例,探讨融入红色基因元素的课程思政大思政格局整体规划、培养方案思政部署、教师思政能力提升、教学思政资源建设等,并进行线上线下混合式翻转课堂开展思政教育的实施探索,以达到完善高校思政教学体系和提升专业课程思政...     

产业层面技术赶超战略及其要素主导模式研究

产业层面的技术赶超体现在产业技术水平、技术研发能力和市场能力三个要素在赶超过程中的变化。产业层面的技术赶超战略有技术主导模式、研发主导模式和市场主导模式三个要素模式。一国产业技术赶超战略取得成功后,不同的要素主导模式对于产业保持领先地位的稳定性和持久性有不同的影响。     

新疆小学教师体育锻炼现状及影响因素分析

本研究采用问卷法调查了新疆小学教师的体育锻炼现状和特征。结果表明,新疆小学教师体育认知水平较高,体育人口比例较低。超过90%的小学教师因校内兼职工作的需要,参与和指导学生体育锻炼,100%的小学教师家人不反对其参与体育锻炼。与家人一起进行体育锻炼是小学教师体育锻炼的首选形式。生活压力和工作压力大是新疆小学教师体育人口比例偏低的主要原因。     

关于 Riesz 代数的乘积和表示(英文)

设｛Ｅｉ∶ｉ∈Ｉ｝是一族ＡｒｃｈｉｍｅｄｅａｎＲｉｅｓｚ代数,Ｒｉｅｓｚ代数的乘积记为Πｉ∈ＩＥｉ,则存在完全正则的Ｈａｕｓ－ｄｏｒｆ空间Ｘ使得Πｉ∈ＩＥｉ是Ｒｉｅｓｚ代数同构于Ｃ（Ｘ）的,当且仅当对每一个ｉ∈Ｉ存在完全正则的Ｈａｕｓｄｏｒｆ空间Ｘｉ使得Ｅｉ是Ｒｉｅｓｚ代数同构于Ｃ（Ｘｉ）的．     

北江大堤渗流分析的一个反问题

北江大堤石角段堤基为强透水深砂层,是经常出险情的堤段．根据该堤段的地形地质情况,以测压管资料作为依据,反求出二维渗流分析的边界条件,通过有限元计算得到与实际情况相符的结果,也与三维数值计算结果一致     

A general boundary solution method for potential flow around a 2D semi-infinite body

１ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｈｅｃａｓｅｏｆｍｅａｎｆｌｏｗａｒｏｕｎｄａ２－Ｄｏｂｓｔａｃｌｅ,ｂｒｏａｄｗａｋｅｗｉｌｏｃｃｕｒｄｕｅｔｏｔｈｅｂｏｕｎｄａｒｙｌａｙｅｒｓｅｐａｒａｔｉｏｎｗｈｅｎｔｈｅＲｅｙｎｏｌｄｓｎｕｍｂｅｒｉｓｈｉｇ...     

合金材料中化学元素的分析方法综述

该文介绍了合金材料中石墨炉原子吸收光谱法等几种元素分析方法的分析及应用情况。     

论我国工科大学生素质教育的三大构成

针对我国高等工科教育的培养目标,提出了文化构成是素质教育的基础;专业知识构成是素质教育的关键及能力构成是素质教育的体现等三要素。