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241.
主要阐述影响双层观光车侧倾稳定性的各项因素;对比分析后,提出采用四个高度控制阀的改进方案,最终通过出口认证试验。 相似文献
242.
结合云南省东南区域联网收费网络的情况,从收费系统网络结构、收费系统硬件平台、收费系统操作平台、收费系统数据库平台、收费系统业务平台等几方面,就如何提高收费网络安全性的问题进行了探讨。动态路由、VLAN技术和3层交换技术的综合运用,使该系统收费网络的稳定运行取得了良好的效果。对今后高速公路联网收费系统的设计和实施具有一定的参考价值。 相似文献
243.
水破坏是造成沥青混凝土路面多种早期病害中的破坏力最大的一种病害,本文结合本地区实际,重点分析了水破坏病害形成的原因,并提出了相应的预防措施. 相似文献
244.
新时期航海职业教育模式探讨 总被引:1,自引:0,他引:1
分析了新时期当前航运业对高级人才的基本要求和需求情况,提出了“订单”培养与航运企业联合办学模式,并对课程教学体系的构建进行了探讨。 相似文献
245.
Contemporary transport planning requires a flexible modelling approach which can be used to monitor the implementation of a long term plan checking regularly its short term performance with easily available data; the original model is periodically updated using low cost information and this allows the evaluation of the changes to the plan which may be required. Such an approach requires models suited to regular updating and to the use of data from different sources. Models to update trip matrices from traffic counts have been available for some time; however, the estimation and/or updating of other model stages with low cost data has escaped analytical treatment. The paper discusses this idea and formulates the updating problem for an example involving a joint destination/mode choice model under various assumptions about the nature of the available data. Analytical solutions are proposed as well as some general conclusions.requests for offprints 相似文献
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C. Vanesa Durán Grados Zigor Uriondo Manuel Clemente Francisco J. Jiménez Espadafor Juan Moreno Gutiérrez 《Transportation Research Part D: Transport and Environment》2009,14(1):61-66
Emissions from the exhausts of marine diesel engines comprises several different gases including NOX. These are currently regulated at the international level under Regulation 13 of ANNEX VI of MARPOL 73/78, but this regulation only applies to new engines and is based on bench tests, for only a single engine designated the “parent engine”. Here, the need to take measurements from across their whole range and once in operation on board a vessel is examined. This would not only improve assessment of new equipment against the current regulation, but would also detect defects in the functioning of the engine. 相似文献
250.
Juan Carlos Molinero Frdric Ibanez Sami Souissi Emmanuel Bosc Paul Nival 《Journal of Marine Systems》2008,69(3-4):271
High frequency sampling was performed in daylight hours along a 35 km transect in the Ligurian Sea to investigate the upper layer zooplankton distribution during the spring phytoplankton bloom. The results show detailed spatial structure and biomass of key zooplankton functional groups, copepods, salps and krill larvae, within the different water masses characterizing this region. Although observed values of total copepod biomass distribution were rather constant along the transect, species-specific patterns were observed in the copepod spatial distribution. The larger species Calanus helgolandicus, as well as Centropages typicus, Oithona spp., and Oncaea spp., were associated with the frontal zone. However, Acartia spp. had a scattered distribution, and Clausocalanus/Paracalanus did not have a clear pattern. In addition, krill larvae were concentrated in the frontal area and salps had a scattered pattern. The cross-shore zooplankton distribution appeared strongly influenced by both the Northern Ligurian current governing inshore waters, which acts as a major flushing forcing, and the Ligurian front, which governs offshore waters and may act as retention area for zooplankton. 相似文献