材料性能和压入深度对球压痕堆积/沉陷的影响

压痕硬度受材料堆积/沉陷影响明显,通过有限元仿真技术分析了材料性能和压入深度对堆积/沉陷的影响,结果表明,随着弹性模量与屈服强度比、压入深度增加或硬化指数减小,材料的沉陷量减小而堆积量增加;当弹性模量与屈服强度比相对较小时,堆积/沉陷受硬化指数的影响较明显。根据建立的等效应变与材料堆积/沉陷的拟合函数关系,可以判断压痕过程的堆积/沉陷状态,从而对计算得到的压痕硬度的准确性进行评判。     

从企业调查探析高职生职业道德教育

职业道德教育一直是高职院校德育工作的重点和难点。文中通过对企业的问卷调查,分析企业对大学生职业道德素养的现实内在需要,探讨从教育观念、教育模式、考核体系等方面加强大学生职业道德教育的对策建议。     

基于工学结合、校企合作的《桥梁结构施工与检测》课程建设成效

文中介绍了广东交通职业技术学院骨干院校建设过程中,专业教师与广东桥梁施工龙头企业共建基于工学结合、校企合作的《桥梁结构施工与检测》课程的成效,“工学结合、校企合作”为本课程建设的特色和亮点。希望对道路桥梁工程技术专业及专业群的其它课程建设能起到借鉴作用。     

《快速公交（BRT）智能系统技术要求》实施效果研究

《快速公交(BRT)智能系统技术要求》以朝阳路和安立路BRT智能系统的建设为出台的重要基础,在运营调度、乘客信息服务、路口信号优先、图像监控、电子设备等十三个方面执行效果良好,大大提高了BRT智能系统建设和运行维护质量,提升了系统运行效率.     

Optimal subwork zone operational strategy for short‐term work zone projects in four‐lane two‐way freeways

Roadside trees in Singapore are regularly trimmed for the purpose of traffic safety and roadside tree‐trimming project is one typical type of short‐term work zone projects. To implement such a short‐term work zone project, contractors usually divide an entire work zone into multiple subwork zones with the uniform length. This paper aims to determine an optimal subwork zone strategy for the short‐term work zone projects in four‐lane two‐way freeways with time window and uniform subwork zone length constraints. The deterministic queuing model is employed to estimate total user delay caused by the work zone project by taking into account variable traffic speeds. Based on the user delay estimations, this paper proceeds to build a minimization model subject to time window and uniform length constraints for the optimal subwork zone strategy problem. This paper also presents a variation of the minimization model to examine the impact of unequal subwork zone length constraint. Since these minimization models belong to the mixed‐integer non‐differentiable optimization problems, an iterative algorithm embedding with the genetic simulated annealing method is thus proposed to solve these models. Finally, a numerical example is carried out to investigate the effectiveness of the proposed models. Copyright © 2010 John Wiley & Sons, Ltd.     

A microeconomic interpretation for the system optimal traffic assignment problem with nonadditive path cost

Using a Bergson–Samuelson welfare function, we outline a microeconomic interpretation of the effects of the non-linearity in the time/cost relationship for travellers in a congested transport network. It is demonstrated that a marginal cost traffic flow assignment following Wardrop's second principle, although it minimizes the total cost of a transport network, may reduce social welfare compared to the market equilibrium assignment based on Wardrop's first principle. A welfare-maximizing assignment model is presented and used to show that if the travellers' utility functions are linear, the assignment that maximizes social welfare will be the same as the assignment that minimizes total network cost, but if users' utility functions are non-linear (reflecting the traditional non-satiation and diminishing marginal utility axioms), the two assignments will be different. It is further shown that the effects of this non-linearity are such that a welfare-maximizing assignment will meet with less user resistance than a minimum total network cost assignment.     

浅谈新形势下路桥企业思想政治工作如何有效发挥作用

文章结合路桥企业工作实际,探讨新形势下思想政治工作有效发挥作用的途径,提出围绕企业中心任务、立足路桥行业特点和以人为本、提高员工整体素质的基本工作思路。     

基于路段风险度的城市危险品运输路径优化选择

以减少运输路径沿线发生事故的风险及减少事故发生后对城市交通的影响为目的,利用交通流理论研究城市危险品运输路径的选择问题.首先利用传统风险管理理论对路段发生事故的风险及发生事故后的交通损失进行分析,提出了路段风险度的定义;利用Dial算法对路段的损失幅度进行计算,从而得到各路段的风险度,建立了风险度最小的危险品运输路径选择模型;然后利用传统标号算法设计了该模型的求解方法;最后通过算例分析了路段交通量与其风险度的关系,得出路段的交通量与路段风险度之间的关系.     

多模式混合动力汽车控制策略研究

针对目前混合动力汽车结构的优缺点及发展现状,提出一种双电机双离合器混合动力结构,在该结构下可实现多种驱动形式,综合各模式优势,可充分利用发动机、电机及电池特性,尽可能地节省能耗.在该混动结构下搭建了基于逻辑门限值和基于ECMS的瞬时优化能量管理策略,仿真及试验分析表明,基于ECMS的瞬时优化能量管理策略与基于规则的策略...     

Ground-truthing social vulnerability indices of Alaska fishing communities

Abstract

Community vulnerability is increasingly evaluated through quantitative social indices, typically developed using secondary data sources rather than primary data collection. It is necessary to understand the validity of these indices if they will be used to inform policy and decision making. This paper presents a ground-truthing effort to validate quantitative indices that characterize the well-being of Alaska fishing communities. We utilized ethnographic data collected from 13 representative communities and a capital assets framework to ground-truth the indices, in which qualitative ranks of vulnerability were compared against quantitative indices. The majority (73.8%) of ranks were in complete or moderate agreement and the results indicate that most of the indices are representative of community vulnerability; yet some variables utilized to create the indices could be modified to better reflect realities in Alaska. Indices of commercial fishery engagement and reliance appeared to be more reliable than socio-economic indicators, particularly for smaller fishing communities. We also confirmed that the indices do not capture political, or ecological factors that affect levels of community vulnerability. We conclude that quantitative indices of community vulnerability are useful rapid assessment tools; however, they should be validated, and complemented with ethnographic data prior to their implementation as policy making and management tools.