Analysis of mechanical behaviors of big pipe roof for shallow buried large-span tunnel

A series of researches on mechanical behaviors of big pipe roof for shallow large-span loess tunnel were carried out based on the Wenxiang tunnel in Zhengzhou -Xi＇ an Special Passenger Railway. The longitudinal de- formations of the pipe roofs were monitored and the mechanical behaviors of the pipe roofs were analyzed at the test section. A new double-parameter elastic foundation beam model for pipe roof in shallow tunnels was put for- ward in Wenxiang tunnel. The measured values and the calculation results agreed well with each other, revealing the force-deformation law of big pipe roof in loess tunnel： At about 15 m in front of the excavating face, the pipe roof starts to bear the load; at about 15 m behind the excavating face, the force of the pipe roof tends to be stabi- lized; the longitudinal deformation of the whole pipe roofs is groove-shaped distribution, and the largest force of pipe roofs is at the excavating face. Simultaneously, the results also indicate that mechanical behaviors of pipe roof closely relate to the location of the excavation face, the footage of the tunnelling cycle and the mechanics pa- rameters of pipe roof and rock. The conclusions can be reference for the design parameter optimization and the con- struction scheme selection of pipe roofs, and have been verified by the result of numerical analysis software FLAC3D and deformation monitoring.     

Pro/E在高职院校《机械制图》中的教学模式探索

三维软件在机械专业中的广泛应用促进了传统机械制图教学模式的更新。本论文以立体表面交线、组合体、半剖视图、装配图等教学内容为例,介绍Pro/E软件在机械制图课程教学中的应用,通过建立3D虚拟模型提升教学效果,提高学生对机械制图课程的兴趣,进而达到提升人才培养质量的目的。     

Unity3D虚拟现实平台的重放功能设计

利用C#脚本和序列化技术,提出一种在Unity3D平台上实现重放功能的设计方法,给出该方法涉及到的部分关键代码。     

Sample maturation calculated using Raman spectroscopic parameters for solid organics: Methodology and geological applications

The shape and shift of Raman peak of solid organics prove to be capable of revealing atomic and molecular level vibration information of aromatic ring structure and its relationship with sample maturation. Raman "D" peaks and "G" peaks of a series of continuously maturated coal samples were measured, and the inter-peak intervals (G-D) and peak height ratios (Dh/Gh) were derived and correlated with the vitrinite reflectance (vRo%) of standard coal samples. As a result, two formulae were established by using the two Raman indices for calculation of Raman reflectance (RmcRo%), which is equivalent to vitrinite reflectance. The formula for calculating Raman reflectance indicative of organic maturation using Raman shift inter-peak interval (G-D) is RmcRo%=0.0537d(G-D)-11.21, which is mainly applicable to matured to highly matured carbonized samples of solid organics; The formula for calculating Raman reflectance indicative of organic maturation using Raman peak height ratio (Dh/Gh) is RmcRo%=1.1659h (Dh/Gh)+2.7588, which is mainly applicable to carbonized samples of solid organics that are over matured or going to be turned into granulated graphite. Preliminary applications indicate that Raman reflectance "RmcRo%" calculated based on results of Raman spectral analysis of solid organics can be used to characterize sample maturation at molecular level, so enjoying extensive prospects in geological applications.     

浅议3D数字全景虚拟景区放映厅在新疆旅游景区开发中的运用

本文探讨了数字虚拟景区的概念、3D数字虚拟景区放映厅在新疆景区开发中的运用价值和开发方式。指出新疆的数字虚拟景区开发处在起步阶段,由于没有运用这一技术,新疆很多景区的内在旅游价值没有得到有效挖掘。3D数字全景虚拟景区放映厅要遵循旅游景区开发原则,本文重点探讨了3D数字全景虚拟景区放映厅在新疆遗址遗迹类、佛教洞窟类和博物馆类景区的运用,期望本文能对将来这一领域的旅游开发做一些理论铺垫。     

国内

科技部出台政策扶持3D打印技术发展 近期,科技部《国家高技术研究发展计划（863计划）、国家科技支撑计划制造领域2014年度备选项目征集指南》（以下简称《指南》）发布,其中明确提出对3D打印技术的支持政策,并将设置专用经费支持3D打印技术研究。     

如何在第三次工业革命中抢得先机？ 3D打印的政策布局建议

曾有业内人士将2012年称为＂3D打印元年＂。就像互联网使得报纸、广播、沟通走向民主化和社会化一样,3D打印技术也会让＂制造业民主化＂和＂社会化制造＂成为可能。 尽管3D打印技术显示出巨大的潜在优势,但距离大规模的工业实际应用还有较长的一段距离。当前,国内的3D打印企业还很难完全依靠市场生存,需要政府对该产业在资金扶持、税收、市场引导等方面实施一系列长期稳定的扶持政策。概括起来,为加快推动中国3D打印技术研发和产业化,特提出如下政策建议：     

2012年度天津市科学研究和技术服务业机构现状分析

对天津市2012年度科学研究和技术服务机构情况进行统计分析,通过对机构的科技活动情况、R＆D活动和科技促进发展等方面的对比分析,反映我市2012年各类研究机构的科技活动现状,以及发展变化趋势.     

Web3D虚拟博物馆在人口较少民族文化抢修保护中的应用研究——以云南省金平县布朗族支系莽人Web3D虚拟博物馆项目为例

随着虚拟博物馆技术研究的广泛应用,基于Web3D技术虚拟博物馆保护文化遗产已受到学术界的广泛关注。以云南省布朗族支系莽人Web3D虚拟博物馆项目为例,对Web3D虚拟博物馆在人口较少民族语言文化抢修保护中的可行性进行了研究。     

地铁盾构分岔式隧道数值模拟及应用

为研究地铁盾构分岔隧道问题,采用FLAC3D三维模拟技术以原始隧道经过简化得到计算分析三维模型,分析了不同分岔角度下的应力、变形问题.研究结果表明:分岔隧道的应力、变形随分岔隧道夹角的增大而减小,应力叠加越来越小,当分叉角度较大时,应力集中峰值开始分岔变为两个峰值;通过与现场监测结果对比,现场监测值与数值模拟结果吻合.