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介绍了所研制的汽车火控制器性能试验台的测量原理,该试验台榀进行点火控制器正常运行状态闭合率的测量、起动状态正常转换点频率的测量,起动状态闭合率的测量、熄火关断时间的测量、切断保护电压和钳位电压的测量等。 相似文献
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SONG Zhi-ming KANG Feng-ju TANG Kai and CHU Yan-jun Marine College Northuxstern Polytechnical University Xi'''' an China 《船舶与海洋工程学报》2003,2(2):40-45
Realistic simulation of underwater scene is always difficult because of the special and complex vision effects in underwater space. Seabed is an important part of underwater environment. This paper describes the methods for seabed scene simulation based on OpenGL. It includes construction of fluetuant terrain based on the random sinusoidal algorithm, simulation of seabed flicker effect by means of circular texture mapping and generation of turbidity effect by using fog techniques. For the application based on the leading high level 3D development environment-Vega, underwater scene simulation is still a difficulty since there is no module for it. Based on the analysis of Vega software and the research on seabed scene simulation methods, a Vega extending module named “Underwater Space” was created through developing module class and extending lynx interface. The module class was designed through developing DLL written in C . The Lynx was extended through developing keyword configure file, GUI configure file and lynx plug-in DLL. The problem that Vega can‘t simulate underwater space, is elementarily resolved. The results show that this module is efficient, easy using, and the seabed scene images am vivid. 相似文献
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为了研究传统基坑工程钢支撑活络头和不同接触面处理(无滚花、直纹滚花、网纹滚花)的新型抱箍式活络头刚度特性和极限承载力,进行了室内原型试验,观察其受力过程和破坏特征,分析了不同设计参数对位移、应变、承载力的影响。试验研究结果表明:抱箍式活络头整体刚度高于单缸千斤顶支顶活络头,在荷载为2 000 k N时,单缸千斤顶支顶活络头位移约是抱箍式活络头的1.5~4倍;在正常使用状态下,试件可重复使用;在达到极限承载力时,抱箍式活络头发生微小脆性滑移破坏,滑移之后可继续承载;由于底部螺栓的夹持作用,抱箍式活络头调节长度短时,即接触面积大时,承载力反而减小;在轴向压力作用下,抱箍式活络头螺栓预拉力基本不变。总体上看,抱箍式活络头具有良好力学特性,有助于提高基坑工程内支撑体系的安全性和稳定性。 相似文献
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洋山深水港一期泊位于2005年底投入试运营,上港集团为其专门设计了航线调整方案,将上海港所有欧洲航线移至洋山深水港作业。分析洋山深水港投产后沪甬两港竞争态势,指出现有方案的不足之处,提出一些针对性的意见和建议。 相似文献
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D. H. Kim J. M. Lee E. H. Park J. H. Song S. I. Park 《International Journal of Automotive Technology》2011,12(3):409-416
A comprehensive study evaluating the performance of biobutanol-blended gasoline in passenger cars was conducted because biobutanol
is considered a better biofuel than bioethanol as it has no water solubility and it has a higher caloric value, giving it
a higher energy value. Several kinds of samples—suboctane gasoline, 8 volume percentage and 16 volume percentage biobutanol—blended
gasoline, and a 10 volume percentage MTBE-blended market sample (as the oxygencontaining gasoline)-were tested to evaluate
the engine performance in terms of the detergency of the intake valves and combustion chambers, power, emissions, and fuel
efficiency. Additionally, the toxicity of the emissions from these biobutanolblended samples was tested in order to assess
the viability of biobutanol as one of the competitive potential substitutes for MTBE as an oxygenator in the near future.
The results show that biobutanol-blended gasoline samples had relatively better detergency, relatively higher power, and similar
levels of emissions compared with those of MTBE-blended gasoline. Formaldehyde was emitted from all of the samples at almost
the same levels and within the error range, whereas biobutanolblended gasoline samples emitted approximately three times the
amount of acetaldehyde than did the suboctane gasoline. This study shows that biobutanol is one of the best alternative bioalcohol
fuels for use in the near future. 相似文献