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A potential solution to reduce greenhouse gas (GHG) emissions in the transport sector is the use of alternative fuel vehicles (AFV). As global GHG emission standards have been in place for passenger cars for several years, infrastructure modelling for new AFV is an established topic. However, as the regulatory focus shifts towards heavy-duty vehicles (HDV), the market diffusion of AFV-HDV will increase as will planning the relevant AFV infrastructure for HDV. Existing modelling approaches need to be adapted, because the energy demand per individual refill increases significantly for HDV and there are regulatory as well as technical limitations for alternative fuel station (AFS) capacities at the same time. While the current research takes capacity restrictions for single stations into account, capacity limits for locations (i.e. nodes) – the places where refuelling stations are built such as highway entries, exits or intersections – are not yet considered. We extend existing models in this respect and introduce an optimal development for AFS considering (station) location capacity restrictions. The proposed method is applied to a case study of a potential fuel cell heavy-duty vehicle AFS network. We find that the location capacity limit has a major impact on the number of stations required, station utilization and station portfolio variety. 相似文献
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根据《新能源汽车产业发展规划》,2025年中国新能源汽车新车销量占比将达到25%[1]。发展新能源汽车,是我国从汽车大国迈向汽车强国的必由之路。在国家新能源汽车战略背景下,基于“原价企划”的理念,以控制新产品设计成本为目标,依托原价技术管理工具,建立零件正向成本精算模型,使零件成本测算工作更加精细化,使其面向成本设计变为常态化,实现在研车型设计成本持续优化。实践表明,原价技术是确保新能源在研车型开发成败的有力武器。 相似文献
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路由器互联端口运用安全策略,有效拦截病毒的传播;在网关路由器、三层交换机上实行ARPA绑定,瓦解ARP病毒的攻击,实用效果良好.在计费UNIX主机上编写的程序,查出实时采集丢失的原始话单,保证原始话单无损到达计费系统,带来的经济效益显著. 相似文献
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The objective of the present study is the assessment of the environmental impact of a bivalent (bi-fuel) vehicle, running either on gasoline or compressed natural gas (CNG). To that aim, a Euro 6 passenger car was tested under various real-world driving conditions. In order to cover the full range of conventional powertrains currently in the market, the tests were also repeated on a Euro 6 diesel passenger car. Both cars were driven in two routes, the first complying with the regulation limits and the second going beyond them. Carbon monoxide (CO), nitrogen oxides (NOx) and particle number (PN) emissions were recorded using a Portable Emissions Measurement System (PEMS). Apart from the aggregated emission levels, in g/km, the exact emission location along the route was also assessed. Natural gas proved beneficial for CO and PN emissions, the level of which always remained below the respective legislation limits. On the other hand, under the dynamic driving conditions with gasoline, the relevant limits were exceeded. Cold start, occurring at the beginning of the urban part, and motorway driving were identified as major contributors to total emissions, especially in gasoline mode. However, the application of natural gas was associated with a penalty in NOx emissions, which were significantly increased as compared to gasoline. Local peaks within the urban part were identified in CNG mode. In any case, the diesel vehicle was by far the highest NOx emitter. 相似文献
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Temperature field and its variation with time are necessary for analyzing the thermo-mechanical performance of mass concrete structures at their early ages. This paper carries out a temperature field simulation analysis for an original segment of a real box girder bridge with the finite element software ANSYS. Two representative exothermic rate models are used to describe the heat-releasing process caused by the cement hydration in concrete. The exothermic rate model that conforms to reality more closely is recognized by comparing the simulation results with the data gathered from the optical fiber temperature sensors pre-embedded in the original segment. The air temperature and wind velocity that constitute thermal boundary conditions are determined in the light of the local meteorological department and correlative research achievements of recent years. Moreover, the consideration for the steel formwork acting as a barrier to heat loss is also proved to be beneficial to improve the simulation effect. 相似文献
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东北师范大学学报自然科学版1979年第一期和1980年第二期上,李复中教授给出了部分质数模全部原根的求法,今天我们称它为间接求法。近年来,国内外没有这方面的论述。作者通过大量的数据推演和论证,做出了形如2^λP^α＋1的质数模全部原根的直接算法（定理）,并给出了这类质数模全部原根的递推公式。这种直接算法对于求2^λP^α＋1的原根更具有灵活性,并减少了计算原根一半的计算量。 相似文献
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实验结果显示:生理盐水对照组小鼠的血清溶菌酶含量(μg/ml)为5.31±0.72,益气养血保元方组为7.02±0.44(P<0.01);生理盐水对照组小鼠的MΦ吞噬率(%)及吞噬指数分别为14.58±2.01和0.1826±0.043;益气养血保元方组分别为52.48±4.12及0.7249±0.1222(P<0.01);益气养血保元方组的MΦ中ANAE及ACPasea活性比生理盐水对照组小鼠明显提高。说明益气养血保元方对小鼠血清溶菌酶活性及巨噬细胞活性有正性作用,提示益气养血保元方具有生物反应调节剂BRMs的作用。 相似文献