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汽油车改装成汽油/LPG双燃料车后,由于汽油和LPG的物化性质和燃烧特性有较大的差别,因而使用同一个点火提前角是不合理的。本文以桑 塔纳LX型轿车发动机为对象,通过台 试验得出燃用LPG时的最佳点火提前角,在原车点火系统的基础上,研制出一套能根据不同的燃料自动切换点火提前角的点火装置,该装置在台架和整车道路试验中都获得较好的结果。 相似文献
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汽车混合器内天然气—空气混合过程的可视化 总被引:1,自引:0,他引:1
本研究制作了透明的混合器模型,把由高速CCD照相机拍摄的纹影画像送入车像处理装置进行处理,调查了空气流量、节气门开度等对混合器内天然气-空气混合过程的影响,探明了混合器出口的混合气的分布特性,并提出了促进混合器内部天然气-空气混合的途径。 相似文献
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Thecancerofgallbladderisacommonmalignanttumorofthebiliarytract ,whichishardtodiagnoseandhasapoorprognosis .Itisalwaysaccompaniedbycholecystolithiasis .The pathologicalresearchforcholecystolithiasis ,adiseasecommonlyandfrequentlywerefoundinclinics ,showedt… 相似文献
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Objective For a brushless AC generator with a rotary rectifier, it is necessary and significant to model and simulate at normal and fault operation states. Methods Two new concepts, namely, Simulink signals and PSB (Power System Blockset) variables, are proposed, and the difference between the two concepts is clarified. Based on the new model for synchronous machines, a simulation model for a brushless AC generator with a rotary rectifier is constructed by Matlab/Simulink/PSB. This new model, which has a speed input terminal and an exciting voltage input one, can simulate the real electrical characters and direct mechanical connection between two synchronous machines perfectly. The rotary rectifier is a three-phase full-wave bridge rectifier which consists of six diodes. The model for the diodes is a macro-model which possesses much better accuracy than an ideal one of switches. Results Based on the present model, some simulation results such as exciting current waveform, phase current waveform and phase voltbge waveform are afftained at several operation conditions. Conclusion The simulation for a brushless AC generator with a rotary rectifier is demonstrated at normal and fault operation states, respectively. The results confirm the presented method. 相似文献
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Objective This paper presents classifications of mental tasks based on EEG signals using an adaptive Radial Basis Function (RBF) network with optimal centers and widths for the Brain-Computer Interface (BCI) schemes. Methods Initial centers and widths of the network are selected by a cluster estimation method based on the distribution of the training set. Using a conjugate gradient descent method, they are optimized during training phase according to a regularized error function considering the influence of their changes to output values. Results The optimizing process improves the performance of RBF network, and its best cognition rate of three task pairs over four subjects achieves 87.0%. Moreover, this network runs fast due to the fewer hidden layer neurons. Conclusion The adaptive RBF network with optimal centers and widths has high recognition rate and runs fast. It may be a promising classifier for on-line BCI scheme. 相似文献