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81.
采用数值模拟的研究方法,对比分析了某纯电车型在高速超速以及驱动耐久工况下动力电池包采用液冷和冷媒直冷两种方案的冷却性能,研究结果表明,对于高速超速工况,相对于液冷方案,采用冷媒直冷电池包温度降低了约10%;对于驱动耐久工况,采用冷媒直冷方案电池包温度降低了约 16%,与此同时,电池包均温性也有所改善。在相同工况条件下,动力电池包冷媒直冷的冷却性能优于液冷。  相似文献   
82.
针对内河船舶防污管理工作中出现的问题:如目标不明确,法制建设滞后,设备配备不完善等,提出相应的改进措施,如:制定总目标,落实工作计划;健全和完善有关法律、法规体系;加大专项投入;完善应急处理体系;加强危防队伍建设等,从而形成有效的工作机制.  相似文献   
83.
随着现代雷达系统的日趋复杂,在现代雷达系统设计、分析和性能测试过程中雷达信号模拟器必不可少.基于高速DSP芯片的雷达回波模拟器具有实时性高,可直接与雷达系统设备对接等特点.论文将介绍一款基于高速数字信号处理芯片ADSP-TS201的雷达回波模拟器设计.  相似文献   
84.
A 3D tyre brush model, which aims to predict the longitudinal tyre characteristic under steady-state conditions by modelling the occurring physical effects in the tyre–road contact patch, is presented. The model includes an analytical method to describe the tyre footprint geometry, the pressure distribution, the slip due to the lateral tyre contour, the slip due to braking or traction and the longitudinal as well as the lateral shear stresses on a flattened tyre. The presented development tool offers a method to investigate different rubber friction data (caused by different tread compounds and/or surface textures) and to analyse its influence on longitudinal tyre characteristics. The tyre design is fixed (same casing, dimension and pattern). The results include the shear stresses as well as the different sliding velocities in the contact patch for different slip conditions. The model was developed for a standard summer pattern design and a standard tyre dimension (205/55R16). It can also be adapted to other tread designs and tyre dimensions. To offer a good comparability between model results and test bench measurements, the surface curvature of an internal test rig is considered.  相似文献   
85.
建立客车内摆门的机构运动模型并推导出运动公式,运用Matlab软件得出内摆门滑槽滚轮中心的运动特性曲线,分析门滑槽及门内置铰链在不同位置对滚轮运动情况的影响。  相似文献   
86.
This paper presents the first route choice model for bicyclists estimated from a large sample of GPS observations and overcomes the limitations inherent in the generally employed stated preference approach. It employs an improved mode detection algorithm for GPS post-processing to determine trips made by bicycle, which are map matched to an enriched street network. The alternatives are generated as a random sample from an exhaustive, but constrained search. Accounting for the similarity between the alternatives with the path-size factor the MNL estimates show that the elasticity with regards to trip length is nearly four times larger than that with respect to the share of bike paths. The elasticity with respect to the product of length and maximum gradient of the route is small. No other variable describing the routes had an impact. The heterogeneity of the cyclists is captured through interaction terms formulated on their average behaviour.  相似文献   
87.
As maritime processes do no stop at sea ports, hinterland operations have to be considered and addressed as well. This becomes obviously on designing and managing seamless cargo and information flows from/to hinterland regions via sea ports from/to transcontinental markets. Nowadays, also security-related aspects need to be tackled in order to enable continuous flows corresponding to security legislations and technical requirements set up in the field of maritime and intermodal hinterland transport. Ensuring transport security within the European transport market requires both adequate security legislations and innovative concepts. While for the maritime sector, including sea ports, security regulations are already in force, hinterland operations (road, rail and Inland Waterway Transport) are only indirectly affected today, either on carrying out transports from/to sea ports or exporting commodities to overseas territories. This results in the need for innovative security strategies and concepts combining maritime with hinterland transport enabling seamless security processes.  相似文献   
88.
曾凡友 《水运工程》2005,(12):64-67,75
通过认真调查岩溶地区地质情况,提出岩溶地区桩基设计、施工的合理方案。  相似文献   
89.
针对现代海战环境下数据的非结构化、分散、广泛、实时等特征,并参照英国海军ADDAM(A Distributed Database Application Management System)系统,提出了实时环境下海军分布式指挥和控制系统RNDCCS(Rintime Naval Distributed Command and Control System).同时,详细讨论了实时环境下分布式数据管理遇到的数据分页,数据的更新和维护,结点恢复等典型问题.  相似文献   
90.
曾峰 《西部交通科技》2010,(4):46-49,73
佛山南庄二桥是V型墩连续刚构桥,梁体采用移动支架悬臂施工,均为动态成形,高空作业,故该桥的施工控制成为保证桥梁施工质量的关键因素。文章介绍了该桥施工监控的控制思路和现场测点布置、测量的内容,重点阐述了结构线形控制的实施过程,为同类桥梁的施工控制提供参考依据。  相似文献   
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