铁路路基地质雷达检测数据智能里程校正方法

针对铁路路基地质雷达(Ground Penetrating Radar,GPR)检测数据里程校正效率低的问题,提出了一种智能里程校正方法。以GPR原始检测数据为数据源,通过构建特征向量和支持向量机识别模型,实现桥梁的智能识别;再根据桥梁里程进行回归计算,得到GPR检测数据的实际里程。采用京九线路基检测数据进行测试,结果表明,本文提出的铁路路基GPR检测数据智能里程校正方法具有较高的精度,里程校正误差约2 m,满足铁路路基检测工程的实际需求。     

A systemic modelling of ground handling services using the functional resonance analysis method

In contrast to air transport safety, safety in ground handling is not concerned only with aircraft accidents but also the Occupational Health and Safety of the employees who work at airport aprons. Ground handling safety costs the aviation industry tens of billions USD every year which raises the questions about the effectiveness of linear safety risk management of Ground Handling Services (GHS). This paper uses the state-of-the-art safety theory to justify and highlight the need for a systemic approach to safety risk management of GHS on the apron. A hybrid Total Apron Safety Management (TASM) framework, based on the combination of Functional Resonance Analysis Method (FRAM), Grounded Theory, Template Analysis and Goals-Means Task Analysis (GMTA) was developed to support systemic safety modelling of GHS. The data that underpins the TASM framework includes extensive literature review, 15 observations, 43 interviews and expert judgement across five international airports. While the TASM framework can be applied in retrospective, prospective and system design analysis to improve both the safety management and the efficiency of apron operations, this paper showcases only one of its application on a case study of a historical safety occurrence. The results of the investigation carried out in this paper clearly demonstrate the benefits of the systemic as opposed to the existing linear approaches to retrospective safety analyses and the suitability of the TASM framework for occurrence analysis and prevention.     

浅谈铁路信号综合防雷系统接地电阻

铁路信号系统机房接地装置的接地电阻在综合防雷系统中十分重要,接地电阻的数值是判断接地装置好坏的唯一判据,测量出接地电阻真值很有必要。为此,分析接地装置接地电阻测量的原理,分析了造成测量误差的原因,希望重视接地电阻测试工作,得出科学准确的接地电阻数据。     

探地雷达在隧道衬砌质量检测中的应用

在隧道工程的质量检测过程中,作为新型无损检测设备,探地雷达因具有携带方便、非破坏性、检测快速、精度高等特点,越来越受到广大技术人员的青睐。被广泛的应用于隧道衬砌的厚度、密实性、钢筋分布情况的检测及进行超前地质预报等。     

城市轨道交通列车电制动地面电阻吸收装置相关参数分析

在地面电阻吸收装置工作的有效区段内,根据列车的电制动特性和供电臂内列车状态的不同,合理地确定制动电阻的技术参数。采用多支路形式的电阻吸收装置,可方便控制电阻吸收装置并可靠吸收列车电制动功率。研究表明,地面电阻吸收装置的输出电流脉动与斩波器的导通比、各支路斩波器的开关滞后角有关。通过分析列车电制动时的最大再生功率与电阻吸收装置的电阻值、电制动时刻牵引供电系统的模型、列车电流、网压降之间的关系,导出了列车电制动时最大输出功率、地面电阻吸收装置的短时功率和持续(等效发热)功率等技术参数的计算方法。给出的计算方法可与现行的城市轨道交通牵引供电计算方法相结合,构成完整的牵引供电计算方法。     

海上搜救立法中的制度设计

内河航道整治的主要手段是通过建设护岸并对墙前土方进行水下疏浚来达到航道等级标准,护岸工程质量优劣不仅在于护岸本身的砌筑量,更要在于护岸的地基处理,下面就护岸的地基处理谈一些认识。     

车地实时无线数据通信方式比较

介绍了多种适合于在运行中的列车和地面之间进行实时无线数据通信的方式，主要是卫星通信、GPRS和GSM-R等，简单介绍各种方式、性能和特点，对它们进行了综合分析比较，指导在实际应用中选择合适的车地实时无线数据通信方式。     

Optimization and integration of ground vehicle systems

This article deals with the optimal design of ground vehicles and their subsystems, with particular reference to 'active' safety and comfort. A review of state-of-the-art optimization methods for solving vehicle system design problems, including the integration of electronic controls, is given, thus further encouraging the use of such methods as standard tools for automotive engineers. Particular attention is devoted to the class of methods pertaining to complex system design optimization, as well as approaches for the optimal design of complex systems under uncertainty. Some examples of design optimizations are given in the fields of vehicle system dynamics, powertrain/internal combustion engine design, active safety and ride comfort, vehicle system design and lightweight structures, advanced automotive electronics, and smart vehicles.     

爆炸固结法和塑料排水板法处理软土地基的对比试验

爆炸固结法是软土地基处理的新方法。在宁启铁路试验段现场爆炸试验的基础上,研究软土地基经过爆炸后的变形特性。在地质情况接近情况下,对比爆炸固结法与塑料排水板加堆载预压法处理的结果表明,爆炸固结法加快了土体前期固结速率和地基沉降速率,有利于缩短施工工期,适用于工期紧的工程,但同时土体也伴随着较大侧向位移;爆炸固结法相对排水固结法,总沉降量有所增加,最终侧移总量基本一致,工后沉降和可比造价较接近,在工期允许情况下工后沉降均能满足设计要求。     

高原融区和多年冻土过渡路段涵洞地基试验研究

运用现场测试方法,对青藏铁路两座拼装式涵洞的基础变形、地基土地温及洞口气温的测试结果进行分析,研究多年冻土区涵洞工程对冻土地温状况、冻融过程、冻土上限变化的影响以及涵洞基础的冻融变形特征。结果表明:多年冻土地区修建涵洞工程后,气温对地温的影响增大,致使涵洞下原多年冻土上限附近地温波动明显,地温年变化深度增大;由于场地冻土条件及地温场沿涵身的变化,涵洞基础变形沿涵身表现出明显的不均匀性。