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861.
人民币升值对国际工程承包的影响与对策分析 总被引:1,自引:0,他引:1
随着近年来人民币不断升值,我国工程企业在境外承包工程中所取得的利润面临汇兑损失的风险,而各种付款结算方式的风险影响因素不同.为更好地应对人民币升值的影响,建议在投标报价时考虑升值和物价上涨的因素,签订合同时需加入保护性条款,分包合同应注意采取措施转移风险. 相似文献
862.
岩溶地区隧道设计的几点思考及建议 总被引:1,自引:1,他引:0
岩溶地区隧道修建中出现的问题较多,尤其是岩溶水对施工安全、结构安全、运营安全的危害,并严重影响建设工期和工程投资。为此从岩溶发育的类型、岩溶对隧道工程的影响和危害等方面,通过近年在株六、渝怀、宜万等铁路项目的工程实例,对岩溶地区隧道工程设计理念、设计技术等进行了系统分析,提出了岩溶地区隧道工程的选线应尽量避开岩溶水的径流带及深部缓流带的建议;针对岩溶危害,在隧道结构设计时应结合安全评价,采取适宜的加强措施;岩溶水一般宜按"宜疏不宜堵"原则治理,辅助坑道、洞口设置等应重视对岩溶水引排的适应性。 相似文献
863.
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865.
重点介绍软土的前期固结压力对于软土地基上各种建构筑物的工程意义、通过室内试验确定软土前期固结压力的方法、室内确定前期固结压力的影响因素和试验注意事项,并综合运用软土前期固结压力和其他相关土工试验指标分析天津滨海地区软土层的应力历史,为工程设计和施工提供可靠依据. 相似文献
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867.
This paper studies the heterogeneous energy cost and charging demand impact of autonomous electric vehicle (EV) fleet under different ambient temperature. A data-driven method is introduced to formulate a two-dimensional grid stochastic energy consumption model for electric vehicles. The energy consumption model aids in analyzing EV energy cost and describing uncertainties under variable average vehicle trip speed and ambient temperature conditions. An integrated eco-routing and optimal charging decision making framework is designed to improve the capability of autonomous EV’s trip level energy management in a shared fleet. The decision making process helps to find minimum energy cost routes with consideration of charging strategies and travel time requirements. By taking advantage of derived models and technologies, comprehensive case studies are performed on a data-driven simulated transportation network in New York City. Detailed results show us the heterogeneous energy impact and charging demand under different ambient temperature. By giving the same travel demand and charging station information, under the low and high ambient temperature within each month, there exist more than 20% difference of overall energy cost and 60% difference of charging demand. All studies will help to construct sustainable infrastructure for autonomous EV fleet trip level energy management in real world applications. 相似文献
868.
The traditional distribution planning problem in a supply chain has often been studied mainly with a focus on economic benefits. The growing concern about the effects of anthropogenic pollutions has forced researchers and supply chain practitioners to address the socio-environmental concerns. This research study focuses on incorporating the environmental impact on route design problem. In this work, the aim is to integrate both the objectives, namely economic cost and emission cost reduction for a capacitated multi-depot green vehicle routing problem. The proposed models are a significant contribution to the field of research in green vehicle routing problem at the operational level. The formulated integer linear programming model is solved for a set of small scale instances using LINGO solver. A computationally efficient Ant Colony Optimization (ACO) based meta-heuristic is developed for solving both small scale and large scale problem instances in reasonable amount of time. For solving large scale instances, the performance of the proposed ACO based meta-heuristic is improved by integrating it with a variable neighbourhood search. 相似文献
869.
This paper examines the association between access to National Cycle Network (NCN) routes in England and an individual’s cycling behaviour whilst accounting for their broader physical activity lifestyle and controlling for their socio-economic circumstances. It identifies a positive association between access to these routes and the total minutes of any form of cycling, and the number of days that cycling takes place primarily for recreational purposes. The broader physical activity of individuals also has a positive association with cycling. Walking appears most likely to be complementary to non-recreational cycling, whilst participation in sport with all forms of cycling, but not with longer duration utilitarian trips. The research also indicates that access to NCN routes has the potential to increase such cycling further, with the exception of longer utilitarian trips, as does a more physically active lifestyle, particularly walking. The main policy implications of the research are to recognise that cycling is intrinsically linked to other physical activity, notably, walking, but that the NCN routes measured in this study primarily support longer duration recreational activity, which is also affected by sporting activity. This suggests that one avenue for achieving the health benefits of cycling may be through promoting NCN routes to harness a more generally active lifestyle and particularly in leisure, whilst sustainability may be further promoted through being linked more to other active travel such as walking. There is a therefore a need to exploit the potential of such NCN route provision as part of this promotion. 相似文献
870.
针对吴淞江大桥主桥P1#、P2#桥墩用Midas软件建模,分别计算了桥墩在受到1000kN横桥向、顺桥向水平撞击力时在桥墩最危险截面处产生的内力。根据桥墩的实际配筋,按照《公路钢筋混凝土及预应力混凝土桥涵设计规范》,计算桥墩实际能够承受的水平撞击力。横桥向水平抗力由P1#桥墩桩基强度控制,为8890kN;顺桥向水平抗力由P2#桥墩强度控制,为7944kN。应用有限元软件ANSYS/LS—DYNA建模分析在高水位时1000t级船舶正撞、侧桥向45°撞击桥墩产生的最大撞击力。根据计算结果评估桥墩的抗船撞能力。 相似文献