A5101861170- Advanced Fiber Optic Sensors
- Magneto-Optical Properties and Applications
- Advanced Fiber Laser Technologies
- Photonic and Optical Devices
- Geophysics and Sensor Technology
- Remote-Sensing Image Classification
- Inertial Sensor and Navigation
- Astronomical Observations and Instrumentation
- Advanced Neural Network Applications
- Structural Health Monitoring Techniques
- Reservoir Engineering and Simulation Methods
- Infrared Target Detection Methodologies
- Groundwater flow and contamination studies
- Enhanced Oil Recovery Techniques
- Fluid Dynamics and Thin Films
- Advanced Image and Video Retrieval Techniques
- Tribology and Lubrication Engineering
- Acoustic Wave Resonator Technologies
- Adhesion, Friction, and Surface Interactions
- Video Surveillance and Tracking Methods
- Optical Network Technologies
- Spectroscopy and Laser Applications
- Fault Detection and Control Systems
Beihang University
2018-2022
University of California, Berkeley
1990
As a typical safety-critical system, satellite has extremely stringent requirements for reliability. However, some components, especially attitude sensors, are prone to suffer from performance degradation or even drastic failure in space environment, which leads serious threats satellite. A series of fault diagnosis methods have been investigated diagnose these failures. due the increasingly complex structure and various operating conditions satellite, it is still challenging task sensor...
The depletion of thin liquid films due to the combined effect centrifugation, surface roughness, and air shear is addressed. As a film flows on horizontal rotating solid surface, it thinned by both inertial forces as well shearing at liquid-air interface. equations describing flow viscous over rough disk are solved numerical techniques. Depletion histories given for several cases involving deterministic random asperities. It noted that roughness markedly enhances retention film. thinner...
Arbitrarily oriented object detection has recently attracted increasing attention for its wide applications in remote sensing. However, it is still a challenge algorithms because of complex scenes, small size, rotation, densely parked. And angle discontinuity at the boundary an important factor restricting model performance. In this paper, we propose anchor-free approach high-precision rotated objects. Firstly, our achieves classification and localization by detecting center point. Secondly,...
Remote sensing image object detection has been studied by many researchers in recent years using deep neural networks. However, optical remote images contain scenes with small and dense objects, resulting a high rate of misrecognition. Firstly, this work we selected layer aggregation network updated deformable convolution layers as the backbone to extract features. The classification objects was based on center-point without non-maximum suppression. Secondly, dynamic gradient adjustment...
The verticality of the borehole determines firmness superstructure, so it is very important to measure borehole. However, existing static manual measurement technology has low efficiency and poor accuracy. In order realize dynamic measurement, reduce cost improve accuracy, this paper proposes error mutual correction method for low-cost IMU according working characteristics combination drill pipe, establishes an online compensation model model. gyroscope accelerometer errors suppresses...
A novel fiber-optic distributed acoustic sensor (DAS) utilizing a LiNbO 3 straight through waveguide phase modulator as generation carrier (PGC) modulation module for the detection of signal is presented. The sensitive principle and demodulation method system based on phase-sensitive optical time domain reflectometer (Φ-OTDR) are described. This scheme solves problems low frequency unstable performance piezoelectric transducer (PZT) in traditional homodyne depends only pulse repetition...
The sensing distance of the traditional phase-sensitive optical time domain reflectometry (Φ-OTDR) distributed fiber disturbance system can only reach about 26 km. In order to increase without introducing new technology and increasing cost, a method processing data by segmenting thresholds was proposed 53.6 locating accuracy is up 20 m. Considering impact noise signal on system's false alarm problem, wavelet threshold denoising based empirical mode decomposition (EMD) proposed. Experimental...
The magnetic field sensitivity is the main source of errors in a fiber optic gyroscope (FOG) and polarization-maintaining (PM) optical coil major sensitive source. In this paper, theory that an orthogonal vertical to light propagating direction PM can induce non-Faraday nonreciprocal phase difference FOG presented. theoretical simulation experimental results show drift proportional cause axial FOG, which closely related skeleton radius depends neither on coil's size nor shape. Furthermore,...
In this paper an algorithmic formulation is given for the synthesis of linear two-phase systems with inherent variability. It assumed that uncertainties in flow system arise due to heterogeneities porous medium. Methods stochastic mechanics are adopted offer a novel approach, whereby absolute permeability taken as spatial process log-normal distribution at each point domain. A correlation structure built into model so achieve realistic representation. addition, constraint on invariance...