南极发电机组顺利启动的方法

本文讨论南极用发电机组高海拔低温启动的问题,提出了多种解决此问题的措施,综合应用了柴油机在高海拔低温启动的多种方法,最终柴油机顺利启动,证明了本文中各种措施及方法的可行性和可靠性。     

连接管路管径对空气弹簧动刚度特性的影响

对于带有附加气室的空气弹簧,主、附气室间连接管路的管径对弹簧刚度特性影响较大.用数值方法对管路内部气体流动进行模拟计算,采用FLUNET软件中模拟分析管路内部的三维流场,研究管径对管路内部流场和弹簧刚度特性的影响.同时,建立带附加气室空气弹簧特性试验系统,测试主附气室间连接管路不同管径时空气弹簧的动刚度特性.试验和模拟的结果表明,随着连接管路管径的增大,主附气室间气体交换量大,管路内部流场较稳定,弹簧动刚度减小.     

INCOTERMS2000的修订及未决问题析要

INCOTERMS(贸易术语解释通则)是外贸实务课程的核心内容。本文旨在通过分析INCOTERMS2000的修改内容及未决问题,对教学内容进行必要的更新和补充,使学习者更加准确地理解和掌握INCOTERMS,以避免学习和工作中的失误。     

Research on Multi-Parameter Evaluation of Electric Vehicle Power Battery Consistency Based on Principal Component Analysis

Electric vehicle power battery consistency is the key factor affecting the performance of power batteries. it is not scientific to evaluate the consistency of the battery depending on voltage or capacity. In this paper, multi-parameter evaluation method for battery consistency based on principal component analysis is proposed. Firstly, the characteristic parameters of battery consistency are analyzed, the principal component score can be used as the basis for evaluating the consistency of the battery. Then, the function that multi-parameter evaluation of battery consistency is established. Finally, battery balancing strategy based on fuzzy control is developed. The basic principle of fuzzy control is to fuzzy the input quantity based on expert knowledge, and the fuzzy control quantity is obtained by fuzzy control rule. The results are verified by test.     

高速铁路隧道长度对压缩波波前变形的影响研究

依据一维可压缩非定常不等熵流动理论,以及黎曼变量特征线方法,在控制方程中计入瞬态摩擦项及传热项,对不同长度无碴隧道内压缩波波前变形进行数值模拟。与国外现场试验比较验证,表明本文计算方法和程序是正确的;在长隧道计算工况下,隧道长度对出口处压缩波的压力梯度影响明显,为进一步研究微压波强度提供依据。     

改进粒子滤波算法在组合导航中的应用

为了提高组合导航定位系统的定位精度和可靠性,分别对扩展卡尔曼滤波(EKF)、粒子滤波(PF)和U卡尔曼滤波(UKF)3种算法进行了分析。通过分析3种算法各自的特点,将PF算法和UKF算法的优点相结合,提出了一种新的粒子滤波算法——U粒子滤波(UPF)算法,并将其应用于GPS/DR组合导航系统中。通过对UPF算法与PF算法在GPS/DR组合导航系统中的仿真研究比较,进一步证实了UPF算法的可行性及计算的精确性。     

浅谈高速公路水泥稳定碎石基层的施工技术

为提高高速公路水泥稳定碎石基层的施工质量,该文对水泥稳定碎石基层的施工技术进行了探讨,论述了施工准备、混合料的配制、水泥稳定碎石的施工、养生等关键性问题。     

掺入石灰改良黄土性能的试验研究

在黄土中掺入不同比例的生石灰，通过室内试验研究，得出不同掺灰比下的各种指标和参数，分析其对黄土性能的影响，为设计和施工提供指导。     

Control and monitoring for railway vehicle dynamics

Over the last twenty to thirty years, railway vehicle dynamics has changed from being an essentially mechanical engineering discipline to one that is increasingly starting to include sensors, electronics and computer processing. This paper surveys the application of these technologies to suspensions and running gear, focused upon the complementary issues of control (which has been reviewed within Vehicle System Dynamics previously) and monitoring (which has not previously been reviewed). The theory, concepts and implementation status are assessed in each case, from which the paper identifies the key trends and concludes with a forward look at what is likely to develop over the next years.     

波纹管应力分析研究进展

评述了波纹管应力理论研究方法的进展情况，围绕解析法、工程近似法和数值法，对波纹管理论研究中的一些主要成果作了较详细的回顾和总结，对各种研究方法作出了评价，展望了亟待解决的一些问题。