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排序方式: 共有2296条查询结果,搜索用时 62 毫秒
991.
伴随着我国社会主义现代化建设的步伐,汽车作为家庭的交通工具,改变了人们的生活方式,推动了社会经济的发展和精神文明的进步。但随着汽车保有量的日益增加,也带来诸如环境污染、能源消耗、交通安全等社会问题,其中汽车道路交通安全问题尤为突出,  相似文献   
992.
Hardware-in-the-loop (HiL) is a testing method in which real-time measurements on physical hardware replace the mathematical model of the particular hardware during simulation. The development of a semi-active suspension prompted the need for such capability. HiL, implemented on a PC with a dSpaceTM board in conjunction with a hydrodynamic actuator, was compared to software simulations of single degree of freedom (DOF) and two DOF systems. HiL was also compared to a physical (ballast-based) two DOF system, comprising the rear suspension of a motorcycle. Comparisons between the HiL and software responses showed its suitability for testing suspension systems, thus providing a viable alternative to ballast-based suspension tests, using available hardware. The research also showed that actuator dynamics, filter types and amounts, and signal reference levels required special consideration.  相似文献   
993.
滕方宏  胡安  耿建明 《舰船电子工程》2006,26(3):121-122,147
通过分析当超级电容器的等效串联内阻与负载阻值接近时直流升压电路的特点,推导出该电路的最大升压比表达式,从而确定系统能保证电网电压恒定工作的超级电容器两端的最低电压。最后用MATLAB/Simulink对模型进行仿真,验证了理论的正确性。  相似文献   
994.
This paper develops a subjective generic methodology for providing ship owners with a transparent evaluation tool for selecting their preferred NOx and SOx control techniques. We quantitatively analyse the merits of the control methods available in marine air pollution control practice using data collected from shipping companies, shipyards and maritime academies. We also prioritize the applicable control techniques with respect to operational shipping environments.  相似文献   
995.
对中速船舶增压发电柴油机动态工作过程进行建模,用VB6.0开发相应的计算程序,计算结果与生产厂家台架试验测试结果吻合良好,证明了程序的正确性和实用性。  相似文献   
996.
介绍了公路工程质检工作在路基施工活动中的重要作用,以及质检工作如何指导路基施工,提高路基施工工作质量。  相似文献   
997.
安飞 《中国船检》2006,(1):56-59
近年来,随着中国航运业、造船业的不断发展,国内二手船舶交易市场日趋火爆。在上海、舟山、广州、温州等地的二手船交易尤为甚之。但是,综观全国船舶交易市场,不仅不完善、不规范的市场操作行为比比皆是,而且混乱无章的市场秩序,也造成了国有资产的大量流失。为此,有业内专家呼吁,强制二手船“进场交易”刻不容缓。  相似文献   
998.
A completely safe engineering solution to the automotive assembly line knuckle ball-joint pull-out problem is achieved using failure analysis based on the “Design of Experiment” (DOE) method. During use, some ball-joints move in their housings or come loose under heavy loads. The purpose of this study is to determine critical production parameters that will eliminate this failure. In this research, the knuckle-ball-joint pull-out problem is examined, and knuckle housing and ball-joint outer diameter limits are re-defined. Four levels of interference between knuckle and ball-joint diameters and 2 levels of knuckle thickness are specified. Experiments are repeated five times using General Variance Analysis. Required pull-out force is determined, and necessary interference is found. New knuckle housing and ball-joint diameters, based on recommended interference values, are determined. It is also found that thickness of knuckle boss does not affect the results. Therefore, the design is unchanged in this region and this reduces costs.  相似文献   
999.
Due to rapid progress in LED (Light Emitting Diode) technology, LEDs have become increasingly prevalent in applications to automotive lighting. This paper studies recent trends of LED headlamps along with various experiments regarding photometric characteristics, glare, and visibility. Experimental results are compared to those of halogen and HID (high intensity discharge) headlamps. LED headlamps are found to be still inferior to conventional headlamps with respect to glare. However, many properties of LED headlamps (luminous intensity, beam width, energy efficiency, and design) are competitive with halogen and HID headlamps. The findings in this investigation will henceforth be reported to the Korean Motor Vehicle Safety Standard (KMVSS).  相似文献   
1000.
Given the inherent complexity of the maritime transportation system, developing effective policy can be challenging. Using risk factors identified by an elicitation and aggregation of expert judgment, a relative-risk rating scheme was developed in the theory-building tradition of the social sciences. The model was empirically evaluated using 18 months of data from the US small passenger vessel sector. The model identified that the top 10% of relatively highest risk vessels accounted for 50% of all marine casualties during the period of examination. A policy for deploying the model nationally is proposed.  相似文献   
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