Goertek Inc.

Weichai Power Co., Ltd.

Yantai Raytron Technology Co., Ltd

Dong Qiu

Xinfeng Yang

Chao Jiang

Xiaodong Cao

Dehui Tong

Xuguang Tan

Peng Wang

Yupeng Wang

Kang Ping

Sumei Wang

Guoliang Chu

Jinjin Hu

Hongchen Wang

Libing Yan

Xianfeng Ren

Youqiang Xiao

Xinzheng Wang

Wenli Chen

Haihao Feng

Jiaxing Wang

Feng Han

Zhenyong Fan

A method for detecting a urea consumption deviation including: calculating a pump pressure correction factor fac; calculating a urea consumption deviation factor A when the pump pressure correction factor fac is within a calibrated range; calculating the urea consumption deviation factor A multiple times, and calculating an average value of A; and comparing the average value of the urea consumption deviation factor A with a calibrated limiting value range, so as to determine whether there is a great deviation between an actual urea consumption value and a theoretical urea consumption value, the calculating the pump pressure correction factor fac comprises: adjusting a pressure of a urea pump to P; adjusting the pressure of the urea pump to P, where Pis smaller than P; recording a time Tduring which the pressure of the urea pump is adjusted from Pto P; and calculating fac=T/(P−P).

Method for detecting urea consumption deviation, and vehicle post-processing system

An engine exhaust aftertreatment device includes a first exhaust treatment unit and/or a second exhaust treatment unit; the first exhaust treatment unit includes a first bypass pipeline and a first connection pipe provided between a DPF and an SCR; the second exhaust treatment unit comprises a second bypass pipeline and a second connection pipeline provided between a DOC and the DPF, one end of the second bypass pipeline being in communication with the turbine front exhaust pipe, and the other end of the second bypass pipeline being in communication with the second connection pipeline; when it is detected that an engine satisfies a starting condition of the first exhaust treatment unit, the first exhaust treatment unit starts; and when it is detected that the engine satisfies a starting condition of the second exhaust treatment unit, the second exhaust treatment unit starts.

Engine exhaust aftertreatment device and method

Provided are a pixel of an uncooled infrared focal plane detector and a preparation method therefor. The pixel includes a structure of three layers sequentially located on a semiconductor substrate from bottom to top. The first layer is a bridge structure including a metal reflection layer, an insulation dielectric layer, a first supporting layer, a first support layer protection layer, a first metal electrode layer and a first silicon nitride dielectric layer. The second layer is a thermal conversion structure including a second support layer, a second support layer protection layer, a thermal sensitive layer, a thermal sensitive layer production layer, a second metal electrode layer and a second silicon nitride dielectric layer. The third layer is an absorption structure including a third support layer, an absorption layer and an absorption layer protection layer.

Pixel for uncooled infrared focal plane detector and preparation method therefor

A method and a system for acquiring the natural frequency of a diaphragm, wherein, the method comprises: selecting test frequency points in a closed space, converting an electric signal into an acoustic signal, directing sound into the closed space, and acquiring the acoustic pressure of each test frequency point; adjusting the electric signal until the acoustic pressure of each test frequency point is the same; converting the adjusted electric signal into an acoustic signal; acquiring the displacement generated by the vibration of the diaphragm; and taking the frequency corresponding to the maximum displacement of the diaphragm as the natural frequency of the diaphragm. By adopting the method and system, the natural frequency of the diaphragm is determined by acquiring the maximum displacement of the diaphragm. Moreover, the process of acquiring the natural frequency of the diaphragm is not affected by surrounding environment, and therefore the acquired result is more accurate.

Method and system for acquiring natural frequency of diaphragm

Disclosed are a device and a method for testing impedance characteristic and expansion performance of a sound absorption material. The device includes a first cavity and a second cavity which are both sealed. The first cavity is communicated with the second cavity through a slit channel. The second cavity is used for placing a sound absorption material therein. The device further includes a sound excitation source whose sounding face is located in the first cavity and used to provide a testing sound pressure. The device further includes two sound pickup sensors whose sound pickup surfaces are respectively arranged in the first cavity and the second cavity and respectively used to detect sound pressure in the first cavity and the second cavity. The device further includes a material for enclosing the first cavity and the second cavity is a hard sound insulation material.

Device and method for testing impedance characteristic and expansion performance of sound absorption material

A method and system for testing a temperature tolerance limit of a loudspeaker. The method includes: selecting a test signal, and determining a test output voltage as a rated voltage of the loudspeaker, so that the loudspeaker reaches a rated amplitude; determining a gain boosting frequency point according to a resonant frequency of the loudspeaker; performing a plurality of tests for the loudspeaker, and in each test controlling the test signal to maintain the gain constant in a frequency band lower than the gain boosting frequency point and increase the gain in a frequency band higher than the gain boosting frequency point, testing and recording a temperature of the loudspeaker till the loudspeaker fails, and recording a temperature at the time of the failure; and determining a highest temperature that is tolerable by the loudspeaker before the loudspeaker fails.

Method and system for testing temperature tolerance limit of loudspeaker

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Weifang, China

Dong Qiu