In the context of increasing dimensionality design variables and complexity constraints, efficacy Surrogate-Based Optimization (SBO) is limited. The traditional linear nonlinear reduction algorithms are mainly to decompose mathematical matrix composed or objective functions in various forms, smoothness space cannot be guaranteed process, additional constraint need added optimization, which increases calculation cost. This study presents a new parameterization method improve both problems...

Small-loop transient electromagnetic (TEM) method can be used for urban underground space detection. Given the mutual inductance between transmitting and receiving coils, early secondary field signals are contaminated by primary signals. To compensate field, bucking coil technology has been utilized in airborne TEM system due to attractive features of technology, which include a compensation effect strong coupling strength body. However, many problems arise when is directly ground small-loop...

There are many conventional methods that have been applied in transient electromagnetic (TEM) random noise suppression such as stacking-averaging. But, when the TEM system works urban areas with strong noise, these not effective due to extremely low signal-to-noise ratio (SNR). We propose a new method combining minimum fraction (MNF) algorithm and deep learning. The MNF neural network (DNN) used extract complex features of signals from noisy signal data. After using improve SNR certain...

In this paper we present initial results of applying Time-Reversed Acoustics (TRA) technology to salt-dome flank, seismic imaging. We created a set synthetic traces representing multilevel, walkaway VSP for model composed simplified Gulf Mexico vertical-velocity gradient and an embedded salt dome. first applied the concepts TRA create redatummed without having perform velocity analysis, moveout corrections, or complicated processing. Each trace approximates output zero-offset, downhole...

Machine learning inversion (ML-inversion) has been widely used in the interpretation of geophysical data. However, because transient electromagnetic (TEM) is not sensitive to response small-size or large-depth abnormal body, there are some problems such as poor imaging accuracy and low-resolution when directly processing raw TEM data with ML method. To solve this problem, we propose use pseudo seismic wavelet (PSW) obtained from wave field transformation perform ML-inversion. Simulation...

Ground penetrating radar (GPR) and transient electromagnetic (TEM) technologies can detect urban underground space efficiently with good sensitivity. These two have complementary advantages, but they are often used independently in detection rarely for the integrated interpretation of geology. To realize high-resolution measurement space, we take shallow structure information GPR as input TEM inversion use transdimensional Bayesian (Trans-Bayes) method to an data. The simulation results show...

It is well known that de Sitter(dS) black holes generally have a hole horizon and cosmological horizon, both of which Hawking radiation. But the radiation temperature two horizons different, so dS do not meet requirements thermal equilibrium stability, brings certain difficulties to study thermodynamic characteristics holes. In this paper, regarded as system, effective quantities system are obtained. The influence various state parameters on in massive gravity space-time discussed. condition...

Road collapse and underground water inrush accidents pose a serious threat to urban safety development. Transient electromagnetic (TEM) method is an effective geophysical for detecting space. However, due the complexity of geological environment, conventional TEM detection methods are difficult meet needs efficient high-resolution To solve this problem, adaptive (AHR) based on pseudoseismic wavelet transform technology proposed in study. The simulation results show that compared with...

Abstract For Anti-de Sitte (AdS) black holes, the isochoric heat capacity of system is vanished, while isobaric not. However, this situation does not hold on for de Sitter (dS) holes. In work, by introducing interaction between hole horizon and cosmological Reissner–Nordström-de (RNdS) spacetime with quintessence, we discuss phase transition system. The results show that only has similar behavior to Van der Waals (VdW) system, non-vanishing fulfills whole thermodynamics Through discussion...

The transient electromagnetic method (TEM) is one of the geophysical methods that can quickly detect underground space information. It obtains resistivity structure medium by inversion technology. traditional only give a unique solution conforming to TEM data, but cannot solve multiplicity problem solutions. Bayesian technology provide uncertainty information this problem. However, its long calculation time makes it difficult apply engineering detection with high real-time performance. To...

Recently, preventing road collapse caused by subsurface voids became an urgent problem that needs to be solved in the urban safety area. While most study field of object detection deep learning method has only focused on objects can acquired GPR B-scan data easily. This paper aims realize under condition lacks verified B-Scan data. In this paper, a image augmentation SinGAN is proposed and YOLOv5 algorithm applied correspondingly detect from both real collected generated The results show...

Surface nuclear magnetic resonance (SNMR) technology based on a prepolarization field is new geophysical method that offers higher resolution for detecting shallow groundwater than traditional SNMR. However, when SNMR system works in noisy environments (such as cities), it difficult to obtain high-quality data because of the low signal-to-noise ratio (SNR). Moreover, air-core coil sensor has relatively large dead time, which can cause early signal loss and further reduce SNR. To solve these...

Based on a model of the early Universe with relativistic Bose-Einstein condensate as source inflationary expansion, we calculate gauge-invariant measure cosmological density perturbations caused by zero-point fluctuations and excitations condensate. An approximate conservation law in perturbation formulation is used to estimate magnitude at horizon reentry. The have scale-invariant spectrum that depends density, mass, coupling constant.

Through-the-Wall (TTW) human targets detection is extensively desired in civil and military applications. Most studies this field have only focused on multiple with large spacing, while the situation of short spacing has yet to be well treated. To solve problem, an accurate robust post-processing scheme developed article for detecting adjacent TTW targets. First, we identify range slow-time planes a high rate. Second, according comparing result between different operating planes, two...

Transient electromagnetic (TEM) method is a geophysical technique suitable for efficient detection of urban underground space, which can be used advance road collapse and water inrush accidents. In actual geological detection, engineers hope to able quickly characterize the space in 3-D, so as assess potential subsidence area or risk. However, due complexity geology, it difficult conventional 3-D imaging techniques take into account both efficiency accuracy. To address this issue, article...

The observed data of transient electromagnetic (TEM) systems is often contaminated by various noises. Even after stacking averages or applying denoising algorithms, the interference system noise floor cannot be eliminated fundamentally, which limits survey capability and detection efficiency TEM. To improve performance TEM receiver, we have designed a low-noise amplifier using current source long-tail differential structure JFET IF3602 through analyzing power spectrum characteristics forward...

Seismic interferometry is a key technology in geophysical exploration, having achieved significant developments constructing virtual seismic responses, overcoming the limitation of traditional exploration. However, non-physical reflections virtual-shot gathers pose challenges for data processing and interpretation. This study focuses on deghosting gather processing. We propose novel method that integrates sparse nuclear norm constraint inversion multi-shot simultaneous deghosting. Initially,...

With the advancement of computer and mathematical techniques, significant progress has been made in 3D modeling foundation piles. Existing methods include semi-analytical model for non-destructive low-strain integrity assessment large-diameter thin-walled pipe piles soil-pile dynamic interaction model. However, these have complex analysis procedures substantial limitations. This paper introduces an innovative streamlined imaging technique tailored detection pile damage. The approach...