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从城市垃圾填埋场沉降的 机理出发,以经典力学中应力-应变之间的关系为基础,建立起城市垃圾填埋场在载荷、蠕变 和生物降解耦合作用下沉降的力学模型,并分别确定在载荷、蠕变和生物降解作用下屈服表 面应力增量的表达式. 通过填埋场沉降的实例计算,该模型得到了较为满意的预测结果.     

软土地区桩端后注浆桩承载性状对比试验研究

桩端后注浆技术是在通过预埋的压浆管对桩底压注水泥浆液,从而减少桩底沉渣和桩周泥皮的负面影响,在工程上逐渐得到广泛应用。结合宁波软土地基中某工程桩基静载荷试验,分析2根相邻后注浆和未注浆试桩的承载性状;通过对桩身预埋钢筋应力计的测试,对后注浆和未注浆桩的桩身轴力传递特性和桩侧阻力发挥特性进行比较分析研究。表明桩端后注浆不仅能提高端阻,还能提高桩端以上一定范围内土层的侧摩阻力,同时,后注浆桩的单桩极限承载力约为未注浆桩的2.5倍。根据以上研究结果表明,桩端后注浆技术能有效改善桩土界面条件,提高单桩承载力和减小桩基沉降。     

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采取简化分析模型的方法,对推土机六向铲计算分析结构进行简化,在此基 础上对推土机六向铲进行受力分析及其数学模型的建立,主要对计算载荷的确定、计算位置 的选择进行了分析论证;对提升油缸力、顶推架支点反力和各铰点反力进行了分析计算. 这些计算不仅为工作装置的机构设计提供计算依据,还为工作装置、履带台车架等零部件强 度、刚度计算提供载荷计算依据.     

军用陀螺专用混合集成电路

阐述了 HIC2 81军用陀螺专用混合集成电路的工作原理、设计思想、采用的工艺及关键技术。采用 PCB双面布线和 SMT技术 ,提高了集成度 ;合理的热设计及电感性负载能力的改善 ,提高了产品的稳定性及可靠性     

IP技术与中国电信行业的国际竞争力

ＩＰ技术与ＩＰ业务在国际上大行其道,强烈地冲击着传统电信网,同时改变着电信市场的竞争格局。ＩＰ技术将成为下一代电信网的核心技术之一,它对中国电信运营商是一种机遇,加快向ＩＰ技术升级,将在未来国际竞争中取得主动权。然而,从美国电信市场竞争格局的变化中,我们强烈感受到外国运营商卷入的压力。因此,ＩＰ技术将成为中国电信业国际竞争力中十分重要的因素。     

GitHub中基于CNN-LSTM的开发者项目推荐模型

作为一个开源项目托管平台,GitHub以多开发者协同参与进行开源项目的开发,开发者作为GitHub的核心元素,保证了整个系统的活跃性,然而,很多新项目在短时间内无法找到合适的协同开发者而被拖延开发周期.针对这个问题,本文提出了一种基于Word2Vec的CNN-LSTM开发者项目推荐模型,该模型以Word2Vec训练开发者访问项目的序列,并将项目进行向量化表示,结合CNN-LSTM模型计算项目相似度并为开发者推荐合适的项目序列.通过提取GitHub中62,031个开发者在2015全年的项目访问数据进行项目预测和相似项目发现实验,实验结果表明,该模型推荐效果较佳,并且可以帮助开发者发现感兴趣的相似项目.     

一种云数据中心资源的动态综合负载均衡调度算法

One of the challenging scheduling problems in Cloud data centers is to take the allocation and migration of reconfigurable virtual machines as well as the integrated features of hosting physical machines into consideration. We introduce a Dynamic and Integrated Resource Scheduling algorithm (DAIRS) for Cloud data centers . Unlike traditional loadbalance scheduling algorithms which often consider only one factor such as the CPU load in physical servers , DAIRS treats CPU, memory and network bandwidth integrated for both physical machines and virtual machines . We develop integrated measurement for the total imbalance level of a Cloud datacenter as well as the average imbalance level of each server. Simulation results show that DAIRS has good performance with regard to total imbalance level, average imbalance level of each server, as well as overall running time.     

Furthest reach of a uniform cantilevered elastica

A uniform elastic cantilever is subjected to a uniformly distributed load or a concentrated load at its tip. The angle of the fixed end with the horizontal is varied until the maximum horizontal distance (projection) from the fixed end to the horizontal location of the tip is attained. The beam is modeled as an inextensible elastica, and numerical results are obtained with the use of a shooting method. For the optimal solution (furthest reach), the tip is below the level of the fixed end. Experiments are conducted to verify the analysis for a heavy cantilever (i.e., only subjected to its self-weight).     

交通荷载下沥青路面车辙三维非线性有限元分析

建立了半刚性沥青路面和柔性沥青路面的三维有限元模型,采用非线性粘弹塑性理论分析了不同交通荷载对沥青路面车辙变形和切应力的影响,并考虑了刹车、路面纵坡对路面车辙的影响。结果表明:在相同荷载作用下,两种路面结构的车辙变形和切应力分布随着路面深度呈非线性分布,但不同路面结构对交通荷载变化的敏感性存在较大的差异;不同的胎压、轮载以及刹车产生的水平力对路面车辙变形有着较大的影响。当胎压为1 050 kPa及轮载为62.5 kN时,路面产生的车辙都大于在标准荷载及标准胎压时路面产生的车辙;在坡度为1%～6%时,路面纵坡对沥青路面车辙深度的影响不明显;在坡道上行车(特别是下行)时刹车是路面车辙过大的主要原因。     

Polarimetric distributed Bragg reflector fiber laser sensor array for simultaneous measurement of transverse load and temperature

A polarimetric fiber laser sensor array based on wavelength/beat frequency hybrid interrogation approach for simultaneous measurement of transverse load and temperature is presented and experimentally demonstrated. Operation principle of the hybrid interrogation approach has been theoretically analyzed, which is validated by our experimental results. The shift of beat frequency and laser wavelength in response to the change of transverse load and temperature allows for simultaneous dual-parameter discrimination. Experimental results indicate that laser beat frequency is highly sensitive to transverse load and temperature while laser wavelength is insensitive to transverse load. And the temperature sensitivities of laser wavelength have the same magnitude as common FBG sensors. The proposed active sensor array with simple configuration has considerable potential applications for future fiber sensor networks.