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IntroductionMagnesium alloys are called green-engineeringmaterial with great development potential becauseof its low density, high specific strength and stiff-ness, superior damping capacity, good electromag-netic shielding characteristics and good machinabil-ity[1]. However, the number of commercially avail-able magnesium alloys is still limited especially forapplication at elevated temperatures. The applica-tions of most common magnesium alloys such asAZ91 and AM60 with outstanding mechani… 相似文献
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随着三维设计软件的普及,客车底盘的设计正在逐渐采用三维设计。本文简要介绍CATIA V5在客车底盘设计中的应用。 相似文献
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为了对机车监控装置和机车控制或微机励磁系统提供光电传感器的模拟信号,以达到机车静态不动车进行测试的目的,设计了采用单片集成电路AD654的手持式模拟信号发生器,现场测试表明其精度高,操作简单。 相似文献
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RTK(Real Ti me Kinematic)定位技术是GPS定位技术的一项飞跃,文章通过工程实例,介绍了GPS-RTK在水下测量中的应用,对其作业流程和关键技术问题进行了分析,得出了一些有益的结论。 相似文献
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目的 探讨炎前因子在过敏性紫癜免疫病理损伤中的作用。方法 采用双抗体夹心ELISA法和硝酸还原酶化学比色法分别检测过敏性紫癜 (SHP)患儿血清肿瘤坏死因子α(TNFα)、白细胞介素 6(IL 6)、白细胞介素 8(IL 8)和一氧化氮 (NO)的浓度。结果 SHP急性期血清 4种炎前因子水平明显高于正常对照组 (P <0 .0 5 )。肾型中活动性肾脏病和 (或 )肾功能不全组较其他组血清IL 6明显升高 (P <0 .0 1 )。恢复期TNF α、IL 8仍高于正常对照组 (P <0 .0 5 )。急性期 4种炎前因子间呈正相关关系。结论 血清 4种炎前因子水平与SHP的发生、发展有关。 相似文献
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目的 探讨白介素 (IL) 6、8、1 0在小儿肾脏病发病机制中的作用、相互关系及与细胞免疫的关系。方法 采用双抗体夹心ELISA法检测 65例肾小球疾病患儿血清IL 6、8、1 0水平 ,McAb A E法检测 54例患儿T细胞亚群。结果 各型肾小球疾病患儿血清IL 6水平降低 ,IL 8、1 0水平升高 ,CD4+细胞及CD4+/CD8+比值均降低 ,IL 1 0水平与CD4+细胞呈负相关 ,血清IL 6、8、1 0分别与尿蛋白定量无相关性。结论 在小儿肾脏病中 ,①血清IL 6水平降低 ,可能是继发性改变 ;②血清IL 8、1 0水平升高 ,参与了肾小球疾病的发生 ;③CD4+细胞、CD4+/CD8+比值降低 ,是肾小球疾病发病的主要原因 ;④血清IL 1 0水平升高 ,与CD4+细胞呈负相关 ,抑制细胞免疫 ,导致免疫功能紊乱。 相似文献
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Crash warning systems have been deployed in the high-end vehicle market segment for some time and are trickling down to additional motor vehicle industry segments each year. The motorcycle segment, however, has no deployed crash warning system to date. With the active development of next generation crash warning systems based on connected vehicle technologies, this study explored possible interface designs for motorcycle crash warning systems and evaluated their rider acceptance and effectiveness in a connected vehicle context. Four prototype warning interface displays covering three warning mode alternatives (auditory, visual, and haptic) were designed and developed for motorcycles. They were tested on-road with three connected vehicle safety applications - intersection movement assist, forward collision warning, and lane departure warning - which were selected according to the most impactful crash types identified for motorcycles. Combined auditory and haptic displays showed considerable promise for implementation. Auditory display is easily implemented given the adoption rate of in-helmet auditory systems. Its weakness of presenting directional information in this study may be remedied by using simple speech or with the help of haptic design, which performed well at providing such information and was also found to be attractive to riders. The findings revealed both opportunities and challenges of visual displays for motorcycle crash warning systems. More importantly, differences among riders of three major motorcycle types (cruiser, sport, and touring) in terms of rider acceptance of a motorcycle crash warning system were revealed. Based on the results, recommendations were provided for an appropriate crash warning interface design for motorcycles and riders in a connected vehicle environment. 相似文献
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Safety warning systems generally operate based on information from sensors attached to individual vehicles. Various types of data used for collision risk calculation can be categorized into two types, microscopic or macroscopic, depending on how the sensors collect the information of traffic state. Most collision warning systems use only either of these types of data, but they all have limitations imposed by the data, such as requirement of high installation cost and high market penetration rate of devices. In order to overcome these limits, we propose a collision warning system that utilizes the integrated information of macroscopic data and microscopic data, from loop detectors and smartphones respectively. The proposed system is evaluated by simulating a real vehicle trip based on the NGSIM data. We compare the results against collision warning systems based on macroscopic data from infrastructure and microscopic data from Vehicle-to-Vehicle information. The analysis of three systems shows two findings that (a) ICWS (Infrastructure-based Collision Warning System) is inadequate for immediate collision warning system and (b) VCWS (V2V communication based Collision Warning System) and HCWS (Hybrid Collision Warning System) produce collision warning at very similar timing, even with different behavior of individual drivers. Advantages of HCWS are that it can be directly applied to existing system with small additional cost, because data of loop detector are already available to be used in Korea and smartphones are widely spread. Also, the computation power distributed to each individual smartphone greatly increases the efficiency of the system by distributing the computation resources and load. 相似文献