新形势下高速公路前期工作推进思路的转变

通过近几年我省高速公路前期工作开展的情况,土地预审和报批是影响前期工作的首要控制因素,在高速公路前期工作逐步下放到地市的大环境下,项目管理基本都采用大包制,设计单位同时承担着设计与专题的双重任务,如何有效推进高速公路前期工作是一个值得思考的问题。     

集通铁路长大隧道GSM-R冗余方案研究

针对集通铁路的长大隧道,论述分布式基站和数字光纤直放站的两种冗余方案,通过分析比较两种方案的单网交织以及同站址双网冗余覆盖方式,推荐采用分布式基站单网交织冗余方案。     

港口系统设备钢轨连接技术

港口系统设备一般外型尺寸和质量较大，多采用截面积较大的起重机钢轨作为行走轨道。根据港口系统设备使用特点和工程施工现场条件，结合码头和堆场结构，借鉴轻轨和重轨的无缝连接技术，对各种焊接工艺进行比较，分析钢轨的材料组成和焊接过程内部组织变化，推荐一种保证设备使用安全和操作人员舒适度、连接质量稳定、便于维护、操作简便、满足港口系统设备钢轨安装现场要求的连接方法和工艺,有助于实现工期目标，可推广应用于矿山、港口、电厂、码头及堆场等大质量机车或起重设备的钢轨连接。     

《电加热道岔融雪系统设备》TB/T3539-2018解读

解读《电加热道岔融雪系统设备》与《客运专线铁路信号产品暂行技术条件汇编——电加热道岔融雪系统设备》标准的共性部分,并从编制背景、标准定位、技术要求、试验方法和检验规则等方面,分析两者之间的差异性.     

浅谈车用电动空压机在新能源汽车上的应用

文章以车用电动空压机为研究内容,对其使用环境进行分析,同时对其在新能源车辆上控制策略做了分析,最后对其管路布局做分析,望对各大主机后续空压机管路布局有所借鉴。     

Bottleneck congestion and distribution of work start times: The economics of staggered work hours revisited

Since the seminal work of Henderson (Henderson, J.V., 1981. The economics of staggered work hours. Journal of Urban Economics 9 (3), 349–364), a number of studies have examined the effect of staggered work hours by analyzing models of work start time choice that consider the trade-off between negative congestion externalities and positive production externalities. However, these studies employed flow congestion models to describe traffic congestion. This study develops a model of work start time choice with bottleneck congestion and discloses the intrinsic properties of the model. To this end, this study extends Henderson’s model to incorporate bottleneck congestion. By utilizing the properties of a potential game, we characterize equilibrium and optimal distributions of work start times. We also show that Pigouvian tax/subsidy policies generally yield multiple equilibria and that the first-best optimum must be a stable equilibrium under Pigouvian policies, whereas the second-best optimum in which policymakers cannot eliminate queuing congestion can be unstable.     

异形网箱生态结构的设计及应用

为保护落成洲整治建筑物头部潜堤根部及LL3~LL5号丁坝根部的现有植被,在标准网箱结构的基础上,研发出异形网箱结构来替代抛石筑堤。异形网箱生态堤在满足工程功能需求的前提下,完整保护了落成洲的原有生态环境,可为航道整治生态结构设计提供参考。     

Identifying preferences for public transport investments under a constrained budget

As urban areas face increasing demands for new transport infrastructure to promote a sustainable future with an increasing reality of constrained government budgets, the debate on whether we should focus on rail or bus-based investments continues unabated in many jurisdictions. Associated with the debate is an emotional (or ideological) bias by communities in favour of one mode, especially rail, which carries much sway at the political level as if there is no budget constraint. This paper presents a stated choice experiment to investigate this context as two unlabelled options described by 20 potential drivers of community preferences for improved public transport, where each choice scenario is conditioned on an estimated construction cost and a total annual transport infrastructure budget for the relevant geographical jurisdiction. This is followed by a labelling of each alternative to reveal whether the option is bus rapid transit (BRT) or light rail (LRT) and to establish whether this additional information influences preference revision. Data is collected in all eight capital cities of Australia in mid 2014. Mixed logit models with heteroscedastic conditioning in terms of the cost of the project infrastructure and whether the alternative is labelled BRT or LRT, provide new evidence on the nature and extent of community modal bias in a budget-constrained choice setting. The conclusions are twofold. On the one hand, if a fully compensatory choice rule is assumed (as is common in all previous modal comparison studies), LRT is predominantly preferred over BRT despite budgetary constraints, similarities in quality of service attributes and the opportunity to choose a greater network coverage for a given construction cost. However, when we allow for attribute non-attendance (a semi-compensatory choice rule), the modal bias is no longer a significant driver of preferences.     

船舶压载舱沉积物接收处置现状、问题及履约管理对策

《国际船舶压载水和沉积物控制与管理国际公约(2004)》要求妥善处理和处置压载舱沉积物,以防止有害生物入侵。为研究履约现状,选取13家从事压载水沉积物清理、接收及处理作业的修船厂进行了系统调研,结果表明普遍存在防污染措施不全、接收处理作业不规范、接收设施技术标准缺失、管理要求不明确等问题。在分析压载水沉积物的来源、危害、产生量等特性的基础上,结合公约和国内要求,从标准规范完善、监管部门协作、接收设施配套、公约法规宣贯和科技研发支撑等方面分析提出了履约对策。研究成果为有关压载水沉积物相关标准规范、技术政策的制定提供参考,有助于加强压载舱沉积物防污染管理,提升国际公约履行水平。     

基于AIS网络的VTS信息智能推送应用研究

文中在通过利用智能手段采用AIS网络对航行计划、交通管制、水文气象等VTS相关信息进行推送的相关领域进行了研究,以便提高船舶信息获取效率,减少VTS服务工作强度。