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1.
在整车开发中,车身防锈对于整车品质和市场定位起着决定性的作用。通过对前期开发车型易锈蚀部位调查,需对车门、地板、机盖及加油口等各个组成部分进行防锈控制。文章主要针对汽车钣金件镀锌板应用进行阐述,分别从镀锌板的分类及应用、优缺点及选择确定原则3方面深入研究,并对车身易锈蚀部位进行系统分析和控制,延长钣金件使用寿命,提高整车品质。  相似文献   
2.
A potential solution to reduce greenhouse gas (GHG) emissions in the transport sector is the use of alternative fuel vehicles (AFV). As global GHG emission standards have been in place for passenger cars for several years, infrastructure modelling for new AFV is an established topic. However, as the regulatory focus shifts towards heavy-duty vehicles (HDV), the market diffusion of AFV-HDV will increase as will planning the relevant AFV infrastructure for HDV. Existing modelling approaches need to be adapted, because the energy demand per individual refill increases significantly for HDV and there are regulatory as well as technical limitations for alternative fuel station (AFS) capacities at the same time. While the current research takes capacity restrictions for single stations into account, capacity limits for locations (i.e. nodes) – the places where refuelling stations are built such as highway entries, exits or intersections – are not yet considered. We extend existing models in this respect and introduce an optimal development for AFS considering (station) location capacity restrictions. The proposed method is applied to a case study of a potential fuel cell heavy-duty vehicle AFS network. We find that the location capacity limit has a major impact on the number of stations required, station utilization and station portfolio variety.  相似文献   
3.
This paper illustrates how to estimate a wave source generating a wave system, including local waves, with the assumption of linear dispersive waves of two dimensions. The estimation of wave source is realized by using an inverse problem. Unfortunately, the inverse problem is ill-posed in the sense of stability, since the wave source information included in local waves diminishes as the distance from the wave source increases. In the area of applied mathematics, there are well-developed methods to tackle ill-posed problems, which are called regularizations. In this paper, three different regularizations which are well known in applied mathematics are introduced and investigated to learn whether they are applicable to the present problem of the estimation of wave source. From the numerical experiments, it is shown that the estimation is realized by the regularizations introduced in this study, so that they can be applied to the determination of a wave source generating a wave system including local waves. Received: June 6, 2000 / Accepted: February 7, 2001  相似文献   
4.
对铁路系统常见的11类43种型号计187台固定性声源进行了测定,噪声级为83.0-131.1dB(A),线性声功率级为89.4-138.6dB。在多数固定性怕源呈中高频特性。  相似文献   
5.
本文对企业提高服务质量的特性、特征进行了分析,提出了企业服务质量的测定和管理方法。  相似文献   
6.
A high performance liquid chromatographic method was developed and validated for the quantitative determination of catechin in rat plasma and its pharmacokinetic study after intragastric administration...  相似文献   
7.
杨巍 《北方交通》2008,(6):109-111
以阜新县南卧线公官营子大桥桥位设计为例,分析、探讨了桥位选择、水文计算及桥孔净长在确定时应注意的一些问题.  相似文献   
8.
山岭重丘区公路受平面、纵断面、横断面的制约,在确定构造物方案时无成熟经验可借鉴。本文通过振浑公路选线,分析了山岭重丘区公路构造物的需求特点和构造物自身优缺点,提出确定山岭重丘区公路构造物的一些经验。  相似文献   
9.
介绍了径向剃齿方法及其技术参数的确定。该方法加工效率高、成本低、调整方便、加工精度高,不仅应用于传统的热前精加工,也应用到齿轮热后精加工。克服了热处理变形难于控制的缺点,达到令人满意的效果。  相似文献   
10.
国内外水泥路面板底脱空判别方法研究   总被引:1,自引:0,他引:1  
文章针对目前水泥混凝土板底脱空判别方法的研究尚不完善的实际,介绍国内外的五大类水泥路面板底脱空判别方法,指出了各种评定方法的优缺点,为公路工程人员在判定水泥板底脱空时提供借鉴。  相似文献   
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