| 1. | The automotive engine noise measurement system based on virtual instrument
基于虚拟仪器技术的发动机噪声测试系统 |
| 2. | Noise level generated by gasoline engine is the key factor that affects the noise level of a vehicle
摘要车用发动机噪声水平是决定整车噪声水平的关键因素。 |
| 3. | High - frequency noises can be checked through barring due to their short wavelengths
对于发动机噪声中的高频噪音，因其波长短，采用阻挡的方式即可达到目的。 |
| 4. | At low speed the cooling fan noise is much lower than the engine noise ; whilst at high speed it always tops the leading noise sources
在低速时风扇噪声要比发动机噪声低很多，而在高速时，往往会成为主要的噪声源。 |
| 5. | Based on noise test results of a four - cylinder gasoline engine , this paper establishes the simulation model by using simulation software gt - power
本文针对某四缸汽油发动机噪声测试结果，运用数值仿真软件gt - power进行建模仿真计算。 |
| 6. | The exhaust noise is the most common sound source of engine noises , and is usually 10 to 15db higher than the overall noise level of the engine
排气噪声是发动机噪声中最主要的声源，其噪声一般要比发动机整机噪声高出10 ~ 15db （ a ） 。 |
| 7. | Because engine noise takes on complicated frequency characteristics , if original noise signal is not collected , the noise control effect will not be evident
由于发动机噪声的频率成分比较复杂，如果采用主动降噪技术不能适时采集到源噪声信号，就达不到理想的降噪效果。 |
| 8. | Using pm inserts can save energy and material . moreover , they have many special properties that are very important to lowering noise , improving lubrication status and advancing the performance of the engine
采用粉末冶金耐磨摇臂镶块，具有节能省材、性能优异等特点，对降低发动机噪声、改善机构润滑性能、提高整机的动力性能等均有着重要的意义。 |
| 9. | A new type of wavelet - exponential damping wavelet is constructed to detect the knocking sound caused by mechanical faults in an engine , experimental results show that by this wavelet effective features of those faults can be extracted from noise signal
为了识别发动机噪声信号中表徵故障的间歇性撞击声，本文构造的一种新型的小波指数衰减型小波函数，它能有效地识别出间歇性撞击声。 |
| 10. | At the same time , by the way of analyzing passengers in electric buses and electric cars on human engineering , it acquire the size of eiect fic buses and elect fic cars " room , 1n order to li attain aerodynamicist ' s ev shape , the thesis cite conclusion from recent paper , then summarize optimum value by synthesizing manufacturing technology and human engineering
噪音低：汽车的噪音、振动大小决定于发动机本身和行驶条件。常规汽车和ev相比，虽然因汽车行驶而引起的噪音、振动无显著区别，但电动机比汽油或柴油发动机噪声要小得多，因此在这方面， ev占有绝对的优势。 |
