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This paper studies the existing problems of message authentication protocols in vehicular ad hoc networks(VANETs) due to their significance in the future of commuting and transportation. Our contribution has been devoted to implementing a new protocol for VANETs so that inherent security problems in past works are resolved. Exclusive security measures have been considered for the system which protects the users against threat of any attack. The new protocol shows a great hardness guaranteed by certificate based 80 bit security which assures messages to remain confidential in any time. Also, new unprecedented features like V2 X which improves system performance effectively have been instantiated. The simulation results indicate that message signature generation and verification both take place in much less time than present comparable rival protocols. 相似文献
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针对RAMS控制体系在转向架设计中的应用进行了研究,在系统寿命周期理论、RAMS各要素要求的实现、RAMS各要素间的关系的处理及如何控制转向架设计中存在的隐患和故障的措施四个方面进行详细的分析.通过分析可以看出,应用RAMS控制体系对转向架设计进行指导,可以极大地提高转向架的设计效率、避免设计风险、减少设计重复更改、减少隐患或危害产生的概率和降低故障产生的影响. 相似文献
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2009年1-4月公路客车市场总体分析 中通统计信息网的统计数据表明:2009年1-4月我国50家主要客车生产企业(占市场95%以上)共销售客车3万5 335辆,其中公路客车2万3 889辆,占客车总销量的67.6%.在公路客车中:座位客车2万3 171辆,占97%;卧铺客车718辆,占3%.2009年1-4月公路客车销量与2008年同期对比情况如表1所示. 相似文献
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目前,金融危机对客车市场的影响已逐渐减弱,但客车企业仍在寻找可以进入的新的细分市场,希望在某一领域有所突破.卖场租车一般由卖场防损部(或客服部、市场部、招商部)提出租车需求报告,提请总经理(店长)批准,报总部备案,然后考察租赁公司(或招标),决定是否采用.近期,笔者对部分城市的该细分市场进行了调研分析,希望能为部分处于窘境中的客车企业提供一些帮助. 相似文献
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