Beihang University

China National Petroleum Corporation

Beijing Sankuai Online Technology Co., Ltd

Bgp Inc., China National Petroleum Corporation

Lijun Xu

Ziran Zhao

Yinian Mao

Bo Fu

Jianguo Ma

Xu Bai

Weiwei Zhao

Meng Hu

Kunpeng Hou

Kunpeng Jing

Jiangtao Sun

Wenbin Tian

Yuedong Xie

Jianping Wei

Yongxin Xiao

Bohan Yao

Xiangdong Ma

Haishen Yang

Baojun Liu

Multi-rotor unmanned aerial vehicle

A dynamic impedance imaging system includes a dynamic impedance imaging sensor, an impedance detection and flow rate measurement module and an electrical impedance tomography (EIT) instrument. The impedance detection and flow rate measurement module is configured to detect an abnormal particle flowing through the dynamic impedance imaging sensor to obtain a flow rate of the abnormal particle, and generate a synchronous trigger signal. The EIT instrument is configured to inject a sinusoidal excitation current into the dynamic impedance imaging sensor under the trigger of the synchronous trigger signal, perform multi-channel interleaved sampling for the abnormal particle according to the flow rate to acquire multi-channel sampled data, and calibrate the multi-channel sampled data to implement impedance tomography imaging for the abnormal particle.

Dynamic impedance imaging system

A method for evaluating accuracy in positioning a receiver point, which is associated with at least one shot point, and for which a derived position data is obtained, wherein a pair of the receiver point and a respective shot point is associated with a characteristic parameter which includes an offset, a velocity of first arrival wave and a first arrival time, the method comprising: step S, constructing a residual vector associated with the receiver point and the respective shot point based on the characteristic parameter; step S, determining a characterization parameter of the derived position data based on the residual vector; and step S, evaluating accuracy of the derived position data based on the characterization parameter. An apparatus for evaluating accuracy in positioning a receiver point is also provided.

Method and apparatus for evaluating accuracy in positioning a receiver point

An all-optical ultrasonic detection device based on light-induced ultrasound and laser interference. In the device, a first laser is connected to an optical switch, the optical switch is connected to a dielectric film and a second laser generates a reference laser beam and a plurality of detection laser beams. The reference laser beam generates a first frequency-shifted reference laser beam and a plurality of second frequency-shifted reference laser beams. The first frequency-shifted reference laser beam generates a carrier signal. The detection laser beams are reflected by the dielectric film and then interfere with the second frequency-shifted reference laser beams. The interference light passes through a fourth fiber coupler and reaches a second photodiode to generate a frequency-modulated signal. The frequency-modulated signal and the carrier signal are input to a frequency mixer to generate a mixed signal. An acquisition unit is configured to obtain a vibration signal for the to-be-detected object.

All-optical ultrasonic detection device based on light-induced ultrasound and laser interference

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Beijing, China

Lijun Xu