基于异构模型的铁路出发旅客衔接时间价值

旅客时间价值是开展区域综合交通一体化研究的重要参数.本文针对现有文献中铁路旅客衔接时间价值研究较少、异构模型计算结果的比较不够充分等问题,以成都铁路东客站出发旅客衔接方式选择SP数据为依托,建立了MNL、ML、LCL、Hybrid等异构模型,对异构模型所得旅客个体和样本总体的等候时间价值、车内时间价值进行了比较.结果表明：模型结构对时间价值求解有较大影响,ML中单侧三角分布模型求解结果较为合理;Hybrid模型在拟合效果上表现优良,但在个体等候时间价值求解结果中呈现出较为明显的偏态性,给总体统计描述带来一定的困难.由于目前尚无关于时间价值的明确比选方法,应用中可考虑取异构模型计算结果的均值.     

DSR试验应变值对复合改性沥青流变性质的影响

通过试验手段对现行规程中动态剪切试验的应变控制范围进行分析,研究不同应变值对复合改性沥青胶结料流变性质的影响。试验结果表明,应变值对沥青胶结料复数剪切模量和高温劲度无显著影响,而对相位角则有显著影响,表明其粘性成分会有所增大;其温度因素对复数剪切模量和相位角影响非常显著。     

高强钢焊接接头CTOD试验允许值与离散性问题探讨

对EQ70高强钢焊接接头进行了低温CTOD试验（-10℃）,用局部压缩法和高K比法保证了疲劳裂纹前沿平直度,但熔合线试样的试验结果较差且具有较大分散性,增加试样个数之后分散性也没有得到改善。不同的预疲方法得到的结果不同,认为应该规定不同的允许值。另外,提出了统一化标准法,为今后接头试样（尤其是熔合线试样）的CTOD试验评定方法提供思路,作为解决离散性等问题的方向。     

Examining stakeholder participation and conflicts associated with large scale infrastructure projects: the case of Tema port expansion project,Ghana

ABSTRACT

Balancing economic activities with socio-environmental considerations has become a global standard for the construction of large scale infrastructure projects, including ports. In this discourse, stakeholder participation and environmental and social impact assessment (ESIA) have been stressed as important tools that can help port managers to co-create values, avoid conflicts and promote inclusive growth. Drawing on qualitative research tools and stakeholder theory, this paper explores whether and to what extent local stakeholders’ inclusion has substantial influence on addressing their socio-cultural concerns and interest. This is illustrated with a case study of an ongoing port expansion project at Ghana’s largest port of Tema. The findings suggest that although the port authority conducted an ESIA and engaged local stakeholders as part of the planning process, this did not translate into preventing the loss of valuable cultural resources of the local communities. The port authority did not place ‘value’ on cultural resources of the local communities that cannot be expressed in monetary terms. Further, lack of good faith engagement with local stakeholders led to conflicts in some cases that triggered a court action and delays. The paper concludes that stakeholder participation if not applied well, can become a ‘post-political’ tool.     

Value creation in the port: opening the boundaries to the market

In the era of fierce competition among ports as elements of value chain systems, the opening of the boundaries to the market represents a crucial challenge that port authority has to cope with, in order to guarantee a lasting economic and social development of the port and its hinterland. We propose a theoretical framework to analyse value creation in the port and its hinterland through two core concepts: resource allocation and interaction. We illustrate such framework with the case of the port of Naples and, specifically, the contribution of the port authority and other port business operators to the value creation process of Garofalo, an export-oriented firm located in its hinterland. A discussion and suggestions for future research are provided in the last section.     

价值工程在工程设计方案优选中的应用

建设项目投资控制贯穿于工程建设全过程,设计阶段是全过程投资控制的关键环节。在工程设计方案优选中引入价值工程理论,并指出价值工程分析的不确定性,应用灰色关联分析理论改进价值工程,使工程造价、使用成木及建筑产品功能匹配合理,有效降低建设投资。     

采空区地层变形产生的隧道附加荷载及变形容许值计算与分析

文章分别计算了采空区上方地层弯曲时对隧道产生的附加荷载q1、q2及地层水平应变时对隧道产生的附加荷载qH,并推导出了采空区地层容许弯曲变形和水平应变数值.结果表明,现行交通部《采空区公路设计与施工技术细则》规定的采空区地基容许变形值较为笼统且偏大,结构偏于不安全.最后,文章根据计算结果对比,对不同围岩级别提出了更严格、更安全、更有针对性和可操作性的隧道对采空区地层变形限制要求,以供广大隧道工作者参考使用.     

基于顾客感知价值的技术降成本方法探讨

本文是基于价值工程理论,从顾客的感知价值角度出发探讨了技术降成本的方法。实践表明,该方法在保证和提高产品市场竞争力的同时,能有效降低其开发和生产成本。     

模糊集和熵权法在船舶耐波性综合评价中的应用

运用模糊集和熵权法开展船舶耐波性综合评价,建立基于横摇、纵摇、垂荡、砰击、甲板上浪、螺旋桨出水和船艏垂向加速度的船舶耐波性综合评价体系,系统阐述该方法的基本原理和实施步骤。该模型结合客观赋权法和主观赋权法的各自特点,依据输入指标的数据矩阵提取备选方案中的有效隐含信息,并反映评价对象所处的背景条件和评价者的意图,其综合权重的确定过程全面且成熟。以30组样本数据为输入,对某油船在不同航行状态下的耐波性能开展评价分析,研究表明,模糊集和熵权法在船舶耐波性综合评价中具有一定的推广和实用价值。     

南疆麦喀高速公路冲击碾压施工工艺

近年来,为提高高速公路的施工质量,增强路基的整体稳定性,降低路基的工后沉降与不均匀沉降,在高速公路的施工过程中,一般都要求对路基做冲击碾压处理。重点分析冲击碾压施工工艺的原理、适用范围、优点、工艺流程与技术要点,以及必要的安全环保措施。实践表明,冲击碾压能够保证的路基的压实质量,而且较为经济。