65 Result(s)
-
Article
5G assisted GNSS precise point positioning ambiguity resolution
This study proposes a model using 5G time-of-arrival data to assist global navigation satellite system precise point positioning ambiguity resolution. Specifically, the model addresses the problem of PPP requi...
-
Article
Initial and comprehensive analysis of PPP time transfer based on Galileo high accuracy service
European Galileo officially provided global users with the initial high accuracy service (HAS) through Galileo satellites for free on January 24, 2023. The emergence of the Galileo HAS provides the possibility...
-
Article
Development of environmental contours from rainfall intensity and duration data for slopes
Rainfall is an important environmental factor affecting the stability of natural slopes. In this study, an environmental contour method is developed by incorporating the infiltration model proposed by Green an...
-
Article
Open AccessComparative nonlinear soil-structure interaction analyses using macro-element and soil-block modelling approaches
In dynamic soil-structure interaction problems, involving the coupling of structure, foundation and soil, the use of a nonlinear macro-element modelling approach may result particularly advantageous not only t...
-
Article
Microseismic signal denoising by combining variational mode decomposition with permutation entropy
Remarkable progress has been achieved on microseismic signal denoising in recent years, which is the basic component for rock-burst detection. However, its denoising effectiveness remains unsatisfactory. To ex...
-
Article
Open AccessShake-table response simulation of a URM building specimen using discrete micro-models with varying degrees of detail
Recent technological advances have enabled earthquake engineering researchers to develop numerical models of increasing complexity, capable of duly reproducing even the smallest structural detail. In the case ...
-
Article
Open AccessIntegrated economic and environmental building classification and optimal seismic vulnerability/energy efficiency retrofitting
A life cycle framework for a new integrated classification system for buildings and the identification of renovation strategies that lead to an optimal balance between reduction of seismic vulnerability and in...
-
Article
Precise frequency transfer model suitable for short baseline link based on GPS single-differenced observations with ambiguity resolution
A frequency transfer model that is suitable for short baseline links is proposed herein. Based on a GPS single-differenced (SD) observation among two stations, the initial values and the corresponding variance...
-
Article
Research on fault recognition method combining 3D Res-UNet and knowledge distillation
Deep learning technologies are increasingly used in the field of geophysics, and a variety of algorithms based on shallow convolutional neural networks are more widely used in fault recognition, but these meth...
-
Article
Low-frequency swell noise suppression based on U-Net
Low-frequency band-shaped swell noise with strong amplitude is common in marine seismic data. The conventional high-pass filtering algorithm widely used to suppress swell noise often results in serious damage ...
-
Article
Separating and imaging diffractions in dip domain on the basis of slope analysis
Fracture-cave reservoirs in carbonate rocks are characterized by a large difference in fracture and cavity size, and a sharp variation in lithology and velocity, thereby resulting in complex diffraction respon...
-
Article
Performance of Galileo precise time and frequency transfer models using quad-frequency carrier phase observations
GNSSs, such as Galileo and modernized GPS, BeiDou and GLONASS systems, offer new potential and challenges in precise time and frequency transfer using multi-frequency observations. We focus on the performance ...
-
Article
An improved method for detecting BeiDou signal-in-space anomalies from precise ephemerides
The signal-in-space (SIS) anomalies caused by satellites and control segments can greatly affect the reliability and safety of navigation and positioning users. The prior information associated with the failur...
-
Article
Modeling and performance analysis of precise time transfer based on BDS triple-frequency un-combined observations
In this study, a model of precise time transfer is developed based on the triple-frequency un-combined observations of the BeiDou navigation satellite system, known as UC-PPP. In this model, except for the tra...
-
Article
Identification of blasting vibration and coal-rock fracturing microseismic signals
Α new method based on variational mode decomposition (VMD) is proposed to distinguish between coal-rock fracturing and blasting vibration microseismic signals. First, the signals are decomposed to obtain the v...
-
Article
Regional disaster risk evaluation of China based on the universal risk model
A comprehensive understanding and scientific evaluation of natural disasters risk is not only the basis of disaster prevention and mitigation, but also the urgent needs of the economic and social sustainable d...
-
Article
Diffraction separation by plane-wave prediction filtering
Seismic data processing typically deals with seismic wave reflections and neglects wave diffraction that affect the resolution. As a general rule, wave diffractions are treated as noise in seismic data process...
-
Article
Automatic event detection in low SNR microseismic signals based on multi-scale permutation entropy and a support vector machine
Microseismic monitoring is an effective means for providing early warning of rock or coal dynamical disasters, and its first step is microseismic event detection, although low SNR microseismic signals often ca...
-
Article
Azimuthal cement evaluation with an acoustic phased-arc array transmitter: numerical simulations and field tests
We developed a novel cement evaluation logging tool, named the azimuthally acoustic bond tool (AABT), which uses a phased-arc array transmitter with azimuthal detection capability. We combined numerical simula...
-
Article
Landslide monitoring in southwestern China via time-lapse electrical resistivity tomography
The dynamic monitoring of landslides in engineering geology has focused on the correlation among landslide stability, rainwater infiltration, and subsurface hydrogeology. However, the understanding of this com...
