企业集团投资项目的财务战略策划

从企业财务战略理论谈起,阐述了集团投资项目财务战略的内外部因素分析及内容、集团投资项目财务战略具体内容和策划流程。     

我国区域性综合物流中心的建设分析

分析了综合物流中心建设的必要条件,提出我国建设区域性综合物流中心的建议,为我国在新形势下开展综合物流领域的建设提供参考。     

新型聚脲防水材料在海洋环境明挖隧道中的应用研究

以博鳌通道工程为例,从施工的可行性、科学性和经济性等方面介绍在海洋环境下明挖隧道中采用喷涂新型聚脲防水材料施工技术,着重阐述了在隧道结构外部进行喷涂新型聚脲防水材料的施工工艺,并指出了在聚脲防水施工中的注意事项,特别是隧道在海洋环境下有效克服了海水的侵蚀渗漏。此项施工技术的应用不仅有效地缩短了工期、节约了成本,还显著提高了防水效果,为类似条件下工程积累了设计与施工的经验。     

加强高校海洋生态环境道德教育的思考

21世纪是海洋世纪,海洋是人类未来的希望,是全球生命支持系统的一个基本组成部分,也是一种有助于实现可持续发展的宝贵财富.在海洋生态环境日益恶化的今天,高校应积极开展海洋生态环境道德教育,提高大学生的海洋生态环境道德意识.阐释了海洋生态环境道德教育的定义,分析了加强高校海洋生态环境道德教育必要性,提出了加强海洋生态环境道德教育的有效途径.     

沥青路面现场热再生技术解析

由于车辆荷载和一些不可抗拒的自然因素的作用,沥青路面经过一定年限的使用后就会出现部分的损伤和老化,因此为了不影响正常的交通秩序需要进行全方面的修缮,热再生沥青技术是重复利用废弃资源,保护环境和节约成本的重要技术,是道路保护的重要发展方向。     

绿色交通概念解析

分析了交通系统对资源环境的影响机理,在考察"可持续发展"、"低碳"、"节能减排"、"循环"等相关概念的基础上,提出绿色交通的内涵,并对其发展要求和具体理念进行了分析。     

青年人居住环境的设计要点分析

青年喜欢接受新观念、新事物、新时尚,渴望有更多的交往和聚会机会;青年人在居住心理上显现出求新、求变、追求时尚等特征,在生活方式上乐于标榜个性化,崇尚独特;在青年人居住环境设计中要把握其心理需求特点,体现人文关怀.     

工业海洋大气环境下焊接耐候钢Q355NHD腐蚀后力学性能研究

随着钢结构桥梁建设需求不断提高、应用日益广泛,耐候钢以其优良的耐候性能,从材料层面为钢桥防腐提供了一种理想方案;但是,由于中国应用耐候钢的时间较短,耐候钢在某些自然环境下的适用性尚未得到充分论证,对其腐蚀后基本力学性能和疲劳性能的认识尚不完善。为此,以钢桥常用的Q355NHD焊接耐候钢及其对接焊缝为研究对象,针对中国滨海城市常见的工业海洋大气环境,通过周期浸润加速腐蚀试验探讨Q355NHD的耐候性能,并对腐蚀后Q355NHD的单调拉伸性能和疲劳性能开展试验研究。基于形貌观察、基体扫描、锈层分析和腐蚀深度计算等多角度分析,发现在模拟工业海洋大气环境下,Q355NHD尽管会形成具有一定致密性的锈层,但其腐蚀速率等宏观指标相比于普通钢并不突出。腐蚀后单调拉伸试验结果表明:腐蚀8周(等效于青岛受工业污染的海洋大气环境下自然腐蚀20年)后Q355NHD母材试件的屈服强度和抗拉强度分别下降8.1%和7.2%,对接焊缝试件的屈服强度和抗拉强度分别下降14.1%和12.5%。腐蚀后疲劳试验结果表明:腐蚀8周后Q355NHD母材试件和对接焊缝试件的设计疲劳强度分别下降35.6%和30.3%,为317.9 MPa和211.0 MPa,但仍然满足《钢结构设计标准》(GB 50017-2017)中相应构造类别的疲劳设计要求。经与既有文献报道的Q355普通钢试验结果对比,表明尽管Q355NHD在工业海洋大气环境中未表现出良好的耐腐蚀性能,不建议按免涂装使用,但其力学性能在不同批次试验结果中处于较高水平,可以视为一种优质的Q355钢材。     

Short-term planning and policy interventions to promote cycling in urban centers: Findings from a commute mode choice analysis in Barcelona,Spain

BackgroundCycling for transportation has become an increasingly important component of strategies to address public health, climate change, and air quality concerns in urban centers. Within this context, planners and policy makers would benefit from an improved understanding of available interventions and their relative effectiveness for cycling promotion. We examined predictors of bicycle commuting that are relevant to planning and policy intervention, particularly those amenable to short- and medium-term action.MethodsWe estimated a travel mode choice model using data from a survey of 765 commuters who live and work within the municipality of Barcelona. We considered how the decision to commute by bicycle was associated with cycling infrastructure, bike share availability, travel demand incentives, and other environmental attributes (e.g., public transport availability). Self-reported and objective (GIS-based) measures were compared. Point elasticities and marginal effects were calculated to assess the relative explanatory power of the independent variables considered.ResultsWhile both self-reported and objective measures of access to cycling infrastructure were associated with bicycle commuting, self-reported measures had stronger associations. Bicycle commuting had positive associations with access to bike share stations but inverse associations with access to public transport stops. Point elasticities suggested that bicycle commuting has a mild negative correlation with public transport availability (−0.136), bike share availability is more important at the work location (0.077) than at home (0.034), and bicycle lane presence has a relatively small association with bicycle commuting (0.039). Marginal effects suggested that provision of an employer-based incentive not to commute by private vehicle would be associated with an 11.3% decrease in the probability of commuting by bicycle, likely reflecting the typical emphasis of such incentives on public transport.ConclusionsThe results provide evidence of modal competition between cycling and public transport, through the presence of public transport stops and the provision of public transport-oriented travel demand incentives. Education and awareness campaigns that influence perceptions of cycling infrastructure availability, travel demand incentives that encourage cycling, and policies that integrate public transport and cycling may be promising and cost-effective strategies to promote cycling in the short to medium term.     

Individual transport emissions and the built environment: A structural equation modelling approach

Increasing CO₂ emissions from the transport sector have raised substantial concerns among researchers and policy makers. This research examines the impact of the built environment on individual transport emissions through two mediate variables, vehicle usage and vehicle type choice, within a structural equation modelling (SEM) framework. We find that new-urbanism-type built environment characteristics, including high density, mixed land use, good connectivity, and easy access to public transport systems help reduce transport CO₂ emissions. Such mitigating effect is achieved largely through the reduced vehicle miles travelled (VMT) and is enhanced slightly by the more efficient vehicles owned by individuals living in denser and more diverse neighborhoods, all else being equal. Our research findings provide some new evidence that supports land use policies as an effective strategy to reduce transport CO₂ emissions.