单拱单柱双层浅埋暗挖地铁车站二次衬砌优化施工技术

北京地铁五号线蒲黄榆车站为22.6 m宽大跨度单拱单柱双层结构,采用中洞法开挖,开挖跨度相对较大,临时支护体系繁多,二次衬砌过程中结构受力转换复杂。文章主要介绍蒲黄榆车站二次衬砌施工分层、分段划分及临时支撑拆除代换技术。     

公路外业调查数据二、三维一体化综合管理平台研究

便携式移动采集设备的发展促进了公路外业调查数据的数字化转变,该类数据具有多源、异构等特点.当前公路外业调查数据存在难以统一组织管理、形象展示、查询统计、对比分析和高效共享等问题.为此,基于数据库技术及二、三维可视化引擎研发公路外业调查数据二、三维一体化综合管理平台,实现了公路外业调查数据的高效在线传输、统一组织及集成展...     

CQ Method for Strictly Pseudo-Contractive Mapping

This paper obtains a strong convergence theorem for k-strictly pseudo-contractive mapping under the framework of Hilbert spaces using CQ method. Due to the fact that non-expansive mapping is only 0-strictly pseudo-contractive, the main result obtained in this paper extends the corresponding main result of Nakajo-Takahashi from non-expansive mapping to k-strictly pseudo-contractive one, where k∈[0,1).     

Fabrication and Interfacial Structure of Ni-YSZ-LSM Porous Scaffold for Solid Oxide Fuel Cells

A novel process route using tape casting and stacking for fabricating porous scaffold of solid oxide fuel cells (SOFC) was demonstrated. The linear shrinkages of anode (Ni-YSZ, YSZ stands for 3% Y_2O_3(mole fraction) stabilized ZrO_2) and cathode (LSM-YSZ, LSM stands for La_(0.8)Sr_(0.2)Mn0_3) were optimized to be uniform with that of electrolyte during sintering, by controlling the content of pore former. The micromorphology and interface microstructure of the cross-section of the porous scaffold were observed by optical microscope and scanning electron microscope, respectively. The element distribution and phase composition were analyzed by energy dispersive spectrometer and X-ray diffraction, respectively. The results showed that the porous scaffold with regular pore shape and high specific surface area was obtained after sintering at 1 350℃. The fabricated porous scaffold had defect free interfacial structures due to the uniform shrinkage of anode, cathode and electrolyte layers. In addition, it was shown that diffusions of Zr, Ni and La caused a progressive boundary between YSZ, Ni-YSZ and LSM-YSZ layers. The interface between anode and electrolyte (Ni-YSZ/YSZ) was mainly composed of Ni, YSZ and a small amount of NiO, and the interface between cathode and electrolyte (LSM-YSZ/YSZ) was mainly composed of YSZ, LSM and a small amount of La_2Zr_2O_7.     

基于遗传算法的近红外光谱建模样品集优化研究

探讨遗传算法优化方法在南丰蜜橘内部品质可溶性固形物的建模集样品选择中的应用,根据优化结果建立了南丰蜜橘可溶性固形物的快速无损检测数学模型。研究选择的波长范围为350—1800nm,应用遗传算法优化建模集样品,优化后建模集样品数量由89个减少到36个,累积变异系数达到99．99％,交互验证均方根误差达到最小。研究结果表明：优化后的建模样品数量大大减少,且保证了南丰蜜橘可溶性固形物的快速无损检测数学模型的稳定性。     

TOR沥青-橡胶在常熟通港路养护改善工程中的应用

概述 常熟通港路是227省道干线公路的一部分。通港路的路面原为水泥混凝土,养护改善工程在修补后的水泥路面上加铺20cm二灰碎石基层,然后加铺两层沥青混凝土,下面层为8cm Superpave20结构的普通沥青混合料．在其上加铺4cm的磨耗层．其中从7K＋360至10K＋400共3km为铺筑TOR沥青-橡胶混合料的试验路。     

Constrained submap algorithm for simultaneous localization and mapping

When solving the problem of simultaneous localization and mapping (SLAM), a standard extended Kalman filter (EKF) is subject to linearization errors and causes optimistic estimation. This paper proposes a submap algorithm, which builds a weighted least squares (WLS) constraint between two adjacent submaps according to the different estimations of the common features and the relationship between the vehicle poses in the corresponding submaps. By establishing the constraint equation after loop closing, re-linearization is implemented and each submap’s reference frame tends to its equilibrium position quickly. Experimental results demonstrate that the algorithm could get a globally consistent map and linearization errors are limited in local regions.     

水泥、二灰稳定废旧二灰碎石路用性能分析

目的:为了研究废旧二灰碎石基层材料的再生利用;方法:通过具体的室内试验,对废旧二灰碎石基层材料的物理力学性能进行了分析与评价,对水泥、二灰稳定废旧二灰碎石路用性能进行室内试验分析;结果确定其技术指标要求,寻求最佳再生途径,为二灰碎石废料的大面积推广具有积极重要的指导意义。     

绥满公路混凝土抗压强度曲线的建立

通过采用绥满公路当地具有代表性的混凝土原材料制成的一定批量不同种类(指混凝土试件中的粗骨料、混凝土强度等级不同)普通混凝土标准试件,并对该混凝土试件的抗压强度与无损检测的参数(超声声速值、回弹值)之间建立起关系曲线,得出绥满公路现场适应性和强度测试精度均优于国家统一测强曲线,在工程检测更具有代表性,便于检测人员参考使用。     

浅谈保证水泥二灰稳定碎石基层质量需要注意的问题

主要是通过合理的配合比设计来克服水泥二灰石基层产生的裂缝。注意消除拌和生产和施工过程中容易被忽略影响质量的因素来进一步提高二灰碎石基层的施工质量。