城市道路指路标志文字信息的布置

过多的信息使城市道路指路标志尺寸较大,设置与维护成本增加,有必要研究指路标志信息布置方法。通过室内仿真试验,比较了高信息量条件下,驾驶人对两种指路标志信息布设方式认知时间的差异。利用现场试验,研究指路标志字间距、行间距与视认距离的关系。结果表明,高信息量条件下采用两块标志显示信息有利于驾驶人阅读,建议字间距为汉字高度的1／10,行间距为汉字高度的1／5。     

矿山法海底隧道废水排水系统设计实践

以青岛胶州湾海底隧道工程为依托,对废水系统排水能力的确定、废水提升方案的选择及废水泵房优化设计等方面进行分析,探讨矿山法海底隧道废水排水系统的主要关键技术。主要结论如下： 1）废水排水能力确定的关键在于隧道的结构渗漏水的定量,常规的水下隧道的结构渗漏水量数据不一定适用于海底隧道,必须实际测量后确定; 2）废水提升方案关系到排水的经济性和安全性,核心在于选取安全可靠的水泵类型; 3）废水泵房优化主要从废水池有效容积、结构设计及设备检修等方面进行展开分析; 4）矿山法海底隧道废水排水系统的设计,必须从隧道实际情况出发,综合考虑各类影响因素,以达到安全、经济的设计目标。     

Hybrid process of fabricating high-quality micro wine-glass fused silica resonators

A new hybrid method, which combines improved glass-blown technology with wet etching, is reported to fabricate micro wine-glass resonators with high-quality fused silica. The optimum placement is compared to achieve the resonators with good shell shape. The typical shell diameter is about 4mm and its thickness covers from dozens to hundreds of micrometers. The etching rates in corrosion solutions with different ratios and at different thicknesses of hemispherical shells are studied. We also conclude how to precisely control the thickness. The corrosion solutions with different ratios of HF solution to NH₄F solution make the spherical shells rougher in different degrees. The best roughness is 0.581 nm in the 1: 8 ratio corrosion solution while the original roughness is 0.537 nm. This fact shows that the resonator remains atomically smooth surface. Based on the glassblowing spherical fused silica structure, the thickness of the resonator is effectively controlled by buffered oxide etch (BOE) technology according to the measured etching rate. The measured resonant frequency of the hemispherical shell at ambient pressure and room temperature is 1.75 kHz of rocking mode which is close to the simulated frequency. Using such a low-cost hybrid approach, we can fabricate high-quality microscale resonators in batch.     

A Micro-Electro-Mechanical System-Based Bulk Acoustic Wave Piezoelectric Disk Resonator for Detecting z-axis Rotation Rate

This paper presents a bulk acoustic wave piezoelectric disk resonator based on a special pair of degenerative modes, to detect z-axis angular velocity. A single piezoelectric disk is operated in its appropriate modes in the k Hz frequency range to achieve this function. This design combines the bulk acoustic wave drive/sense mode with lead zirconate titanate resonator which improves device's performance and simplifies its structural complexity. The operation principle of piezoelectric disk resonator is given and validated by finite element method,and the scale factor of piezoelectric disk resonator is 0.977 μV/[(°) · s-1] without any amplification section.The results of impedance analysis for the prototype in the air, which is fabricated on lead zirconate titanate wafer by Micro-Electro-Mechanical System process, show that the resonant frequency of the piezoelectric disk resonator is about 190 k Hz. Moreover, the measured frequency split between drive and sense mode is about290 Hz without any tuning methods. At last, a closed-loop driving and detecting circuit system is designed and its modulation/demodulation method is studied, preliminary experiments show that this device is not sensitive to acceleration, but is sensitive to angular velocity, its performance parameters need follow-up experiments.     

盾构可编程控制器(PLC)系统设计研究

研究目的：自主开发设计盾构可编程控制器（PLC）系统，掌握盾构国产化研究的关键技术。 研究方法：针对盾构的结构特点，进行可编程控制器（PLC）的选型；通过对土压平衡盾构的工况、工作流程及功能要求分析，从系统设计、硬件配置、程序编写等方面对PLC控制系统的设计研究进行详细阐述，体现了检修维护方便，扩充灵活，降低造价的设计优点；从土压平衡控制、姿态控制、推进缸速度与压力协调控制等方面，对盾构的主要动作的控制原理进行了说明；并介绍了计算机控制系统对盾构进行参数设置、故障诊断，远程监视、数据采集分析的基本功能。 研究结果：已基本完成PLC控制系统的设计，为实现盾构可编程控制器（PLC）控制系统的国产化打下了基础。 研究结论：对盾构可编程控制器（PLC）系统的设计研究，已列入国家“863”攻关计划，为国产盾构的开发提供了试验参考。     

公路施工区限速方法效果评价研究

文章对公路典型施工区内三种限速方法的效果进行了分析评价,结论表明:限速标志所能取得的效果很有限,不能达到人们预期的效果;相比之下,旗手具有较好的减速效果,能够使平均速度降低10.4km/h;而减速垄的效果则十分明显,使平均速度降低了23.3km/h,但同时造成通行能力大幅度下降。     

电气安全保护装置在T880E掘进机上的应用

TBM是隧道开挖的工厂化施工机械,其用电设备多,自动化程度高,技术复杂,对电气设备的安全保护要求较高.介绍其中的几项保护装置,如TJB高压电缆快速接头、高压电缆绝缘及接地线连续保护装置、低压母线绝缘监视装置在TBM上的应用.     

航道维护计划可变与不变因子浅析

通过内河航道维护计划各因了变化规律的分析，展示其特点，提出新形势下降低航道维护成本，合理制定维护计划的策略与途径。     

高速公路隧道监控量测及应用

新奥法思想是把坑道周围岩体和各种支护结构作为一个完整支护体系的一种支护理论和方法,而监控量测则是新奥法中不可缺少的重要组成部分,通过监控量测来决定围岩和支护结构的承载-变形-时间特性。结合云南元磨高速公路隧道群的现场监控量测,简介隧道围岩现场监控量测方法和对量测数据的处理、分析及其应用。     

浅谈大梅沙隧道质量监理

质量监理是保证隧道工程质量的重要环节。针对隧道建设中的新情况和新问题，以大梅沙隧为例，介绍了施工中质量监理的方法和实践。