IPS预应力鱼腹梁体系受力机理和有限元分析

阐述了IPS鱼腹梁主要工作机理和理论分析,通过MIDAS GTS NX有限元软件的二维平面(水平面)分析与理正深基坑软件(垂直剖面)分析相结合的方法,在其他学者所提出的刚度基础上,对基坑鱼腹梁的平面受力体系整体建模,并结合具体的工程实例,验证其理论分析是合理并可行的,对比分析不同工况下的基坑变形位移,证实了预应力鱼腹梁能够有效的控制基坑位移变形。     

相邻基坑相互影响二维有限元分析

以国内某市典型的两个相邻深基坑同时开挖的工程为例,使用Midas/GTS4.2.0有限元分析软件建立平面模型模拟出了两基坑同时开挖时的相互影响关系,得出了两基坑在开挖过程中的变形、支护结构体系的受力变化以及位移趋势。     

GTS1-2型数字探空仪基值测定解读

本文对GTS1-2型数字探空仪基值测定过程、基测数据及其变化进行了基本解读,试图让值班人员对每一种现象、每一个步骤、每一个数据有清楚的认识,能够及时发现和纠正基测过程中可能出现的错误。     

AES算法在配送物资跟踪系统中的应用

针对配送物资跟踪系统中RFID标签的相关限制,设计了基于AES算法的数据加密方法.实现了AES算法的相关程序,对AES算法应用于配送物资跟踪系统进行了相关的安全性分析.     

IEEE802.15.4多时隙下GTS性能分析及配置优化

IEEE802.15.4标准的保障时隙(GTS)机制可分配多个时隙,用于保障实时性数据的传输。针对非竞争接入期多时隙下GTS性能分析的不足,利用网络微积分法分析时延和吞吐量服务曲线及其与能耗的关系,改进IEEE802.15.4传感器节点模型,建模仿真研究GTS参数对网络性能(时延、吞吐量及能耗)的影响。仿真结果表明：根据高低突发性数据率的情况,最优化配置下的GTS可以满足实时性数据的传输。     

似膏体充填开采沉陷的FLAC3D数值模拟

基于FLAC^3D数值模拟软件与Midas/GTS辅助建模技术,采用Mohr Coulomb本构模型,对西马煤矿南一采区工业广场保护煤柱范围内的1327工作面进行了似膏体充填开采后的地表移动变形预计分析,并将其结果与概率积分法预计结果进行比较,得出FLAC^3D模拟结果（该结果符合实测数据）。分析结果表明:FLAC^3D数值模拟不需要确定繁杂的参数,而是以实际钻取的煤岩的物理参数为计算依据,较概率积分法更为简捷;研究成果为似膏体充填开采沉陷预计分析探求了一种更为高效的研究方法,也是对于传统概率积分预计方法的有效补充。     

In Depth: Inscribing the Indian Landscape

When India was colonised by the British in the 18th and 19th centuries, it was systematically surveyed and delineated in map form for administrative and political purposes. Here, Anuradha Mathur and Dilip da Cunha urge a new, ‘deeper’ reading of the landscape that fully acknowledges the multiple uses and potential initiations of public spaces. Copyright © 2007 John Wiley & Sons, Ltd.     

降雨入渗及地震作用下边坡稳定性研究

边坡滑坡给社会经济和人民生命安全带来了巨大威胁,降雨和地震是边坡滑坡的两大诱因。以云南省某矿山边坡作为研究对象,取样后在室内进行岩石力学实验,得到后期工作所需的岩石力学参数,利用霍克布朗准则推导出岩体的力学参数,运用理论计算和数值模拟分析降雨和地震对边坡稳定性影响,结果表明：1）在降雨入渗作用下,边坡出现滑坡主要是静水压力造成的;2）在地震作用下,当地震峰值加速度为0.1g时,有效塑性区主要位于边坡中下部,当增大地震峰值加速度,其范围向坡脚移动,当加速度为0.3g时,塑性区出现贯通趋势。     

The curvilinear integral method: computer realization and testing 1 (under non-roportional reversed axial force and torque)

The curvilinear integral method seems to be the first not to search for loading cycles; damage accumulation (and the corresponding fatigue life) is computed in terms not of cycles but of differentials of loading (on differential level). Following the classical mathematical differential-integral method, and considering the mutual change of the loading components, a differential of load change ds during dt has been defined as a short element of a ‘trajectory’ (path in appropriate coordinates). The damage differential on ds is dD. Integrating dD to D, the loading is allowed to be arbitrary: non-cyclic, nonproportional (with different component variations), and random. This feature of universality makes the method applicable to real structures for life prediction. The concept of the curvilinear integral has been published previously; this paper provides additional information and details about the mathematical and computer realization of the method and its first testing using a new program. Experimental data from LBF-Darmstadt Germany on the cast iron material GTS45 have been used, under reversed (alternating) axial and shear stresses: in phase, out of phase and of different frequencies.