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本文介绍了汽车行驶综合记录仪智能控制系统的整体结构、工作原理和软、硬件设计.系统采用AT89C51单片机为控制核心,对汽车行驶过程中的运行速度和连续运行时间进行实时监控,当超过规定的安全值时系统可自动提示和报警.经过实际的运行和调试,该系统实现了对汽车行驶时间、速度及车辆制动状态的智能控制. 相似文献
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为了提高车辆的运行平稳性,基于车辆-轨道耦合动力学建立高速列车-无碴轨道-桥梁耦合系统的垂向动力学模型.运用D' Alembert原理和模态综合法,导出高速列车—无碴轨道—桥梁耦合系统的二阶常微分方程组,采用Newmark-β数值方法对系统运动方程组进行求解.以谐波型激扰模型来模拟轨道几何不平顺,研究了轨道不平顺的波长和波深对车辆平稳性的影响.结果表明:长波不平顺对Sperling指标影响较大,即对列车运行平稳性影响较大,存在最不利波长. 相似文献
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现阶段我国经济高速发展,要想保持经济持续稳定铁路运输系统必不可少,除此之外,保证车辆车钩缓冲系统能够稳定运行也尤为重要,其作为铁道车辆顺利运行的主要因素之一,为我国铁路事业做出巨大贡献。因此,充分掌握铁道车辆车钩常见故障极其重要,应时刻注意。此文通过研究目前我国铁道车辆车钩缓冲系统常见故障,根据事实情况以及相关个人经验对车钩系统故障进行一定分析,并提出相关参考意见,仅供参考。 相似文献
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本文概述了中低速磁悬浮列车的技术特点,重点介绍了国内中低速磁悬浮列车悬浮系统和牵引系统的工作原理。磁悬浮车辆悬浮运行的特性,较之传统轮轨车辆,很好地克服了轮轨黏着、运行噪声等问题,可以有效延长磁悬浮车辆的使用年限,减少日常的维护检修。磁悬浮列车有可能成为未来理想的陆上交通工具。 相似文献
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周泽明 《农业装备与车辆工程》2009,(2)
在汽车行驶过程中,轮胎过于膨胀或处于充气不足状态都会影响汽车安全性,如何对汽车运行中轮胎气压进行检测意义重大.汽车轮胎压力检测系统是用于汽车行驶过程中实时、自动监测轮胎气压,对轮胎漏气和低气压进行报警.以保障行车安全的一种系统技术.通过对汽车轮胎压力检测系统工作原理及应用进行阐述,使得含有此系统车辆的维修和运用具有实际价值. 相似文献
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针对某型车辆动力及辅助系统高原运行过程中出现的问题,结合车辆动力舱空间和结构限制,分别从进气中冷、滤清器、供油系统进行改造研究,提出各系统改造方案;通过计算分析、数值仿真和试验分析等手段,对方案进行验证,分析改造技术对发动机高原运行性能的影响。结果表明,在满足各限制条件的基础上,发动机性能得到恢复,为改造技术手段在实车上的应用提供指导。 相似文献
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行驶中的拖拉机,发生故障,往往造成车辆毁坏、人体伤害甚至死亡的严重事故。怎样预测拖拉机运行故障呢?一、看1.看仪表电流表、机油压力表、水温表和气压表等是用来指示车辆有关系统工作情况的,如果其指示读数异常,就说明拖拉机有故障。2.看消耗拖拉机的燃油、机油和冷却水的消 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献