基于瞬态电流影响的汽车线束选取分析

本文以某自卸车为例,通过实验对汽车线束设计过程中极易忽略的瞬态电流、线束温度等问题,提出了汽车电路中导线截面积、接插件等线束部件的选取原则和注意事项,为整车运行的可靠性提供参考。     

如何提高汽车线束设计的可靠性

汽车的线束设计关系到车辆的各种功能的实现和行车安全,文章简要探讨了几点提高汽车线束设计可靠性的措施.     

有关汽车线束的修理技术分析

近年来,随着我国科技水平的不断提高,推动了汽车产业的发展,较之以往汽车各方面的性能均有了较大幅度的提升,并且功能也越来越多。电子控制技术在汽车中的广泛应用,也使汽车中的线束不断增多。一旦汽车线束出现问题,势必会影响整车的性能和正常使用,而此时就需要对线束进行修理。基于此点,针对汽车线束的修理技术进行阐述。     

汽车线束设计及可靠性研究

随着社会经济的不断发展,汽车在人们生活和工作中发挥的作用越来越大。在此背景下其安全性也受到越来越多人的关注,汽车线束作为汽车结构中重要的组成部分,其设计和可靠性同样受到人们的关注。本文这对汽车线束设计及可靠性做一研究,希望能为汽车线束设计及其可靠性研究提供参考。     

刚性矿用自卸车电气系统部件-整车线束研究与设计

刚性矿用自卸车在冶金矿山、水利水电工程等领域应用广泛。在总体原则的指导下对刚性矿用自卸车电气系统的整车线束进行了研究。对刚性矿用自卸车的整车线束的选择进行了阐述,对线路的插件与安装进行了设计,同时研究了整车线束的安装与控制,为刚性矿用自卸车安全稳定运行提供了一定的保障。     

谈汽车电气线路与线束

在汽车电气系统中,线路和线束的设计是一项较为重要工作的;汽车电系的工作可靠性,在很大程度上是靠线路和线束质量来保证。     

电动汽车用电池建模及整车动力性能仿真

为研究电动汽车的电池和整车的动力性能,建立了电动汽车的蓄电池、电机及整车的力学和数学模型,基于ADVISOR软件建立了车辆、电池、电机和整车的仿真模型。根据整车设计技术参数进行车辆行驶性能仿真,选取CYC_ECE循环工况,得出了速度和SOC值变化的仿真结果。与实车试验结果对比表明,建立的模型是合理,动力系统设计可行。     

进气系统噪声优化

随着汽车行业技术水平的不断进步,用户对汽车各项性能要求也越来越高,NVH性能是汽车重要性能指标之一,而进气系统的NVH性能是整车NVH性能重要的组成部分,加强对进气系统噪声控制是解决车辆噪声的一种有效途径。文章针对某款轿车在加速过程存在较大轰鸣声,并对车内噪声产生较大贡献问题,诊断出进气系统设计存在缺陷,通过合理设计消音元件对进气系统进行优化设计,并校验了增加消音元件之后的消声效果。结果表明,增加谐振腔和多孔管结构后,进气系统噪声水平改善明显,加速轰鸣声明显减弱,对整车内噪有着极大改观,提升了整车NVH品质。     

汽车线束设计浅谈

在汽车电路的网络体系中,汽车线束占据着主体性的位置,要是没有它就没有汽车电路。现今社会人们对汽车的要求在不断地发生着变化,安全性、舒适性、经济性和排放性使人们购买汽车的时候首先会考虑到的几个条件。虽然汽车线束的复杂性在不断地加强,但是车身能为汽车束线提供的容量的大小会降低。因此,越来越多的设计所追求的最关键的一点变成了对汽车线束综合性能的改变,同时,汽车线束声场方,将放弃原来对线束后期设计和制造的关注和大量投入的模式,与汽车主机生产方结合,展开前期开发已经成为一种主要的模式。笔者在这里对线束设计和制造的实践经验进行了分析,探讨了通常情况下线束设计的步骤和基本要领。     

汽车机械式变速器的可靠性优化设计研究

汽车在使用期间,借助自身内部系统的相互协调,在发动机动力的作用下将汽车带动起来。变速器在控制汽车速度中起到十分重要的作用。车辆车速的控制是利用变速器的协调作用,改变内部结构配置,对车速进行调整。设计车辆变速器时,应根据汽车动力行需求,确保汽车内部零件强度与刚度的可靠性满足车辆变速要求。现通过建立数学模型,优化设计汽车机械式变速器的可靠性。     

Low doses of a red wine ingredient figh diabetes in mice

Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said.     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.     

Cooler temperatures inductive to locust outbreaks

Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.     

Molecular motor assembly of a biomimetic system

Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.     

To serve and promote science development via innovation

CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.     

Tracing the origin and early radiation of birds——Paleornithologist ZHOU Zhonghe

With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants."     

The Information Environment and Universal Service

This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.