基于模糊层次分析的连续梁桥健康状态的评估

以模糊层次分析法为基础,通过桥梁健康状态评估的隶属度函数和桥梁技术状态评估等级之间的量化关系,建立桥梁健康状态评估模型,利用计算的各因素隶属度值和权重的结果,获得各层次的模糊评价集。根据最大隶属度原则来评估桥梁结构对应的技术状态等级,用其结果来指导桥梁的维修养护决策。     

新能源动力耦合方式对节能效果的影响

从不同能量源的动力耦合方式入手,并考虑到当前车辆的典型控制策略和实现方式,根据车辆假定的行驶工况,对比分析了多种方案;从系统成本、关联能量、回馈效果等多个角度进行分析,分析出最优方案;并结合系统原理,转化为相关动力源的设计参数,为车辆前期设计开发提供技术支持。     

某重卡转向桥用工字梁设计及强度校核

本文介绍了某重卡9.5吨转向桥用工字梁的主要技术参数及结构设计,并对该工字梁在几种典型工况下进行了受力分析及强度校核。通过与材料的力学性能对比及台架试验验证得出该工字梁的设计是安全、可靠的;与现有成熟产品7.5吨转向桥用工字梁相比,该工字梁的结构是合理的,并具有轻量化的特点。     

通行条件对公共汽车碳排放的影响

针对中国公共汽车能耗与碳排放水平高的现状,基于车辆性能稳定的前提,研究通行条件对碳排放的影响。首先,对工况和通行条件进行划分。然后,以上海市北安跨线为例,在调研数据的基础上,统计各种交通干扰对应的工况并计算其碳排放水平,发现拥堵的作用效果最显著,其次是交叉口。最后,分析载客量对碳排放的影响,空载、半载、满载情景下碳排放水平近似线性地轻微增加,但人均碳排放量显著减少。     

Analytical Solutions to the Fundamental Frequency of Arbitrary Laminated Plates under Various Boundary Conditions

In recent years, as the composite laminated plates are widely used in engineering practice such as aerospace, marine and building engineering, the vibration problem of the composite laminated plates is...     

Effect of variable message signs on driver speed behavior on a section of expressway under adverse fog conditions—A driving simulator approach

Variable message signs (VMS) are used to provide dynamic information and one current application is to show different speed limits under different conditions. As speed is an important contributor to road accidents and also affects driver speed behavior, the present study focuses on how effective traffic advisory information is when helping drivers to divert from potentially dangerous conditions. Graphical representation of an Expressway section made it easy to isolate the effects of speed etc. by drivers with information provided through VMS under adverse fog conditions. Understanding and reacting to the VMS system by drivers is essential for its success. If drivers do not react by changing speed behavior then the VMS system will fail and further implementation may cease. In this paper an Analysis of Variance model, which is appropriate to the proposed experimental conditions, is used to study how subjects (drivers) will perceive provided information and also to find the effect of VMS on driver speed behavior on the simulated Expressway section.     

The trophic state of the Baltic Sea a century ago: a model simulation study

We apply a 3-D circulation model with a biogeochemical module (ERGOM) for the simulation of trophic conditions in the Baltic Sea a century ago. One aim is to provide reference or background data for nitrogen, phosphorus and chlorophyll, which is required for the implementation of the European Water Framework Directive (WFD). We assume that the situation a century ago serves this purpose well. Model input for this long-term simulation study are the regionally differentiated riverine and atmospheric nutrient loads to the Baltic Sea, which were compiled and calculated for a situation 100 years ago on the basis of various literature sources. For the mixed surface layer of the open Baltic Sea, we suggest maximum winter concentrations for dissolved phosphorus (dissolved inorganic nitrogen) of 0.23–0.35 (2.7–3.7) mmol/m³. Maximum chlorophyll-a concentrations are between 1.8 and 2.4 mg/m³. The concentrations of all parameters for different coastal waters vary in a wide range, depending on exposure to nutrient sources. Our nutrient concentrations for the situation a century ago are close to early measured data (1950–1960) and suggest that this data is suitable as reference data, as well.     

浅谈接触网线岔的通车条件与技术标准

本文通过对线岔的通车条件与技术标准的对比,希望人们在注重技术标准的同时,还要多了解一些制定这些技术标准的依据即通车条件。而通车条件也是事故抢修中制定抢修方案的主要依据。在对通车条件分析的同时,对某些技术标准也提出了质疑。     

深水半潜式平台大型生活区结构强度研究

结构安全是保证深水半潜式钻井平台在恶劣海况、复杂载荷作用下正常作业的基本前提,而大型生活区往往因参与平台总强度而发生结构损伤,开展对生活区危险区域结构强度和位置布置研究是半潜式平台安全作业运营的重要保障。采用随机性设计波方法确定波浪参数,开展含生活区的半潜式平台结构响应计算和变形分析,总结主导生活区高应力区域的典型波浪载荷工况。通过横向和纵向布置位置对比分析,总结生活区参与平台总强度的规律。结果显示,主导生活区结构强度的典型波浪载荷工况为中纵剖面扭矩和中纵剖面剪力工况;当生活楼前侧围壁与平台首部侧围壁齐平时,参与平台总强度程度较大;生活楼长度增加会增大其参与平台总强度程度;生活楼的长度应避免与平台立柱内侧板的间距相当;分析结果可为半潜式平台生活区设计提供技术支持。