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221.
The advantages offered by the electronic component LED (Light Emitting Diode) have resulted in a quick and extensive application
of this device in the replacement of incandescent lights. In this combined application, however, the relationship between
the design variables and the desired effect or result is very complex and renders it difficult to model using conventional
techniques. This paper consists of the development of a technique using artificial neural networks that makes it possible
to obtain the luminous intensity values of brake lights using SMD (Surface Mounted Device) LEDs from design data. This technique
can be utilized to design any automotive device that uses groups of SMD LEDs. The results of industrial applications using
SMD LED are presented to validate the proposed technique. 相似文献
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以出口铁路货车KZ1型转向架制动梁滑块磨耗套产品为对象,从产品结构分析、模具设计、注塑机选型、工艺参数确定等方面开展工艺研究.模具型腔采用1模1腔、冷流道、2板模设计,模具四角以圆导柱为动定模导向机构.浇注系统采用盘形浇口进胶方式,以减少熔接痕数量;在分型面上开设排气槽,所有排气槽均与模具外侧联通,以实现良好排气;在产... 相似文献
224.
汽车制动系统的稳定性直接影响整车安全,而制动跑偏又是多年的老问题。文章从设计和生产加工的角度分析了引起制动跑偏的原因,并介绍了一种制动力调节机构(可调式弹簧制动气室)的工作原理,表明制动系统零部件加工及制造误差引起的积累误差是造成制动跑偏的主要原因,而这个积累误差是不可控的,也是无法消除的。指出要解决这个问题必须尽可能提高各零部件加工质量,减小积累误差;同时在制动系统中增加制动力调节机构,通过制动力的调节来弥补积累误差。 相似文献
225.
Diego Iannuzzi Flavio CiccarelliDavide Lauria 《Transportation Research Part C: Emerging Technologies》2012,21(1):321-337
The installation of stationary ultracapacitor storage devices, as widely recognized, allows the recovery of the braking energy for increasing the energy efficiency as well as a better pantograph voltage profile. In the paper a new methodological mean is proposed for determining the fundamental characteristics of this kind of storage device, characterized by high power density, interfaced with the railroad by a bidirectional dc-dc converter. More specifically, the parameters of the storage system can be determined by employing an optimization technique which in a quite general way is able to take contemporaneously into account several aspects in an integrated manner. Some considerations are performed for properly taking into account the stochastic aspects of the design procedure. Numerical simulations with respect to a case study are presented, pointing out the potentiality of the tailored technique. Experimental results are also reported, with reference to an electromechanical simulator, in order to put in evidence the effectiveness and the actual implementation of the proposed optimization technique. 相似文献
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为解决某轻卡加速轰鸣问题,文章基于Nastran有限元法,对车架第二横梁及优化方案进行了模态分析,并通过NVH振动测试试验,有效解决了该车型加速异响轰鸣问题,满足设计目标要求. 相似文献
230.
Central to the concept of Transit Oriented Development (TOD) is a retail core situated around stations. However, successful retail near light rail transit stations has been elusive. Despite significant implications for land use, transportation, and economic development planning, little research exists to explain the gap between TOD concept and reality. We hypothesize that the density, diversity, and design characteristics central to the theory of TODs drive retail success. We implement a TOD Index proposed in the literature to score 474 light rail station areas in 11 metropolitan areas according to the presence and magnitude of those density, diversity, and design characteristics. A series of robustly-developed multilevel models support our hypothesis: TOD Index scores significantly predict station area retail employment, ceteris paribus. An evaluation of its subcomponents individually (block size, which relates to walkability; land use mix; and activity density) suggests activity density may be the driving force in this relationship. Our research works to move the conversation away from an assumption that transit stations and retail naturally co-exist and toward more intentional station area design choices demonstrated to drive retail employment. 相似文献