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3-d Full-Waveform modeling and Analysis of Induced Polarization and Magnetic Viscosity Effect in Time-domain Electromagnetic Method

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IEEE TRANSACTIONS ON GEOSCIENCE ANd REMOTE SENSING 2023年 61卷

作者： Liu, Huaishi Zhao, Xuejiao Yu, Yibing Qiu, Shilin Ji, Yanju Jilin Univ Coll Instrumentat & Elect Engn Changchun 130000 Peoples R China Jilin Univ Key Lab Geophys Explorat Equipment Minist Educ Changchun 130000 Peoples R China

With the improvement in the accuracy of time-domain electromagnetic method (TdEM) observations for geophysical exploration, abnormal diffusion phenomena have become a more salient focus of research. In particular, the induced polarization (IP) effect and magnetic viscosity (MV) effect are often observed in the exploration of polymetallic ore, with IP effect leading to a negative TdEM response, and MV effect generating a power-law decay of -0.6 to 1.4 in the late stage response. Ignoring these effects can lead to incorrect data interpretation. Therefore, to model and analyze both IP effect and MV effect accurately, a 3-d numerical modeling method for IP-MV effect is proposed. The Cole-Cole conductivity and Cole-Cole susceptibility models are approximated in the time domain using the multiple-zero-pole (MZP) method. Then, the diffusion equations for the electric and magnetization intensity fields are derived as control equations, while the 3-d modeling of the IP-MV effect with full waveform is realized based on the improved recursive convolution technique and finite-difference time-domain (FdTd) method. The effectiveness is verified by comparing with the 1-d numerical integration solutions. The response characteristics of IP effect and MV effect are analyzed with full trapezoidal waveform, and a complex model including IP-MV effect is discussed. It is demonstrated that IP-MV effect can be better observed at the ON-time stage. The proposed method can effectively model the diffusion process of IP-MV effect with the full waveform, which can be helpful for improving the inversion accuracy and detection precision for complex geological formations.

关键词： & nbsp 3-d modeling induced polarization (IP) effect magnetic viscosity (MV) effect time-domain electromagnetic (TdEM) method

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4-d Spatiotemporal detection and modeling of Free-Bending Pipelines in Cluttered 3-d Point Cloud

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IEEE TRANSACTIONS ON INSTRUMENTATION ANd MEASUREMENT 2021年 70卷

作者： Zhang, Jie Sun, Junhua Beijing Technol & Business Univ Sch Artificial Intelligence Beijing 100048 Peoples R China Beihang Univ Sch Instrumentat & Optoelect Engn Beijing 100191 Peoples R China

Analyzing free-bending pipelines in cluttered 3-d scenarios is a vital and challenging task in industrial manufacture and maintenance. It is beneficial in understanding the structure of pipelines and monitoring pipeline spacing for accurate assembly. Most existing pipeline analysis algorithms focus on regular straight pipelines and only depend on 3-d spatial cues. In this article, we propose a novel pipeline analysis framework based on 4-d spatiotemporal pipeline representation. The framework allows multiple pipeline analysis tasks ranging from detecting free-bending pipelines in point clouds and extracting 3-d skeletons to modeling complete 3-d pipelines. The 4-d pipeline representation formulates a free-bending pipeline as a 3-d cylinder sequence and incorporates 3-d spatial geometrization of each cylinder frame into temporal continuity of the frames. The multitask pipeline analysis starts from a cylinder patch and is performed on sequential pipeline frames using spatiotemporal cues. Finally, surface registration-based optimization refines pipeline skeletons, detected point cloud, and generated complete models simultaneously. The proposed algorithm is verified on real pipeline scenarios. It can deal with challenging free-bending pipeline shapes, clutter, and occlusions. Compared with existing algorithms, our algorithm achieves more comprehensive tasks and higher detection performance. The modeling of complete pipelines reaches an overall accuracy of 0.33 mm. Finally, we present a thorough analysis concerning the applicability of our algorithm from multiple aspects.

关键词： 3-d modeling 3-d pipeline reconstruction 3-d pipelines engine manufacturing point cloud spatiotemporal detection

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Thermal Infrared Radiative Transfer modeling in Urban Areas by Considering 3-d Structures and Sunlit-Shadow Temperature Contrast

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IEEE TRANSACTIONS ON GEOSCIENCE ANd REMOTE SENSING 2023年 61卷

作者： Zheng, Xiaopo Wang, Tianxing Nerry, Francoise Guo, Youying Huang, Zhihao Sun Yat sen Univ Sch Geospatial Engn & Sci Zhuhai 519082 Guangdong Peoples R China CNRS ICube UdS F-67412 Illkirch Graffenstaden France

Land surface temperature (LST) is a crucial parameter needed to study the thermal environment in urban areas. Currently, it can be restored from thermal infrared (TIR) measurements based on various LST retrieval algorithms. However, the expected urban LST retrieval accuracy of < 1 K is difficult to achieve because knowledge is lacking on how to correct the impact from the surface of 3-d structures and the sunlit-shadow temperature contrast. Although an analytical TIR radiative transfer model over urban area (ATIMOU) has been proposed, the temperature contrast between sunlit and shadowed areas has not been well-managed yet, thus leading to its inapplicability in daytime TIR observations. This study develops an extended ATIMOU (E_ATIMOU) that considers the impact from both 3-d structures and sunlit-shadow temperature contrast. According to the simulations based on E_ATIMOU, if such impact is not properly accounted for, a 4.43-K bias can be potentially introduced to the ground brightness temperature of a street canyon under the condition of wavelength of $10 similar to\mu \text{m}$ , ratio "sunlit-road area/total-road area" of 0.5, shadowed wall and road temperature of 300 K, and the sunlit-shadow temperature contrast of 5 K, which emphasizes the necessity of addressing this impact during the LST retrieval in urban areas. Moreover, E_ATIMOU has also been validated by intercomparing with the discrete anisotropic radiative transfer (dART) model. The discrepancy between the two models for the calculated ground brightness temperatures is found to be < 0.1 K for various urban scenarios, indicating that the E_ATIMOU is in good agreement with dART.

关键词： Roads Land surface temperature Urban areas Temperature measurement Land surface Analytical models Solid modeling 3-d modeling land surface temperature (LST) Index Terms radiative transfer thermal infrared (TIR) urban areas

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3-d time-domain electromagnetic modeling based on multi-resolution grid with application to geomagnetically induced currents

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PHYSICS OF THE EARTH ANd PLANETARY INTERIORS 2021年 312卷

作者： Gao, Jingyu Smirnov, Maxim Smirnova, Maria Egbert, Gary Lulea Univ Technol Lulea Sweden Univ Cologne Cologne Germany Oregon State Univ Corvallis OR 97331 USA

Time-domain electromagnetic modeling in 3-d requires the solution of partial differential equations discretized on a grid. The finer grid resolution is usually required to describe rapid variations of the electromagnetic field in the near-surface, where the source and small-scale anomalies present. Since the electromagnetic field diffuses in the lossy medium, its variations become smoother with depth. The conventional finite-difference modeling approach using the staggered grid extends the fine grid resolution (needed for shallow layers) to all depths. It results in over-discretization of the problem and redundant computational costs. Here, we apply the multi resolution (MR) grid approach to the time-domain electromagnetic modeling (TdEM). The MR grid allows us to decrease the grid resolution with depth and consequently reduce the number of degrees of freedom without compromising the accuracy of the solution. We implement a way of treating the loop source in TdEM modeling such that the definition of the source term is based on the Biot-Savart law;this allows separation of the loop source from the grid, making the source simulation more flexible. To verify our new TdEM modeling, we perform several synthetic tests. We also apply the algorithm to model the geomagnetically induced electric field (GIE). Such modeling is an essential part of estimating hazards caused by geomagnetically induced currents (GIC). In contrast to frequency-domain modeling primarily used in previous studies, the time-domain GIE modeling allows us to consider the time variability of the source in the ionosphere in real-time. For more realistic simulations, we use a large-scale 3-d resistivity model of Fennoscandia. An example of the MR grid GIE modeling highlights the areas of high GIE contrasts and shows that the real inhomogeneous 3-d resistivity distribution and realistic source geometry are necessary for a better estimation of GIC.

关键词： Time-domain electromagnetic Multi-resolution grid 3-d modeling Impressed source term Geomagnetically induced currents

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Petrofacies prediction and 3-d geological model in tight gas sandstone reservoirs by integration of well logs and geostatistical modeling

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MARINE ANd PETROLEUM GEOLOGY 2020年 114卷

作者： Cao, Binfeng Luo, Xiaorong Zhang, Likuan Lei, Yuhong Zhou, Jinsong Chinese Acad Sci Key Lab Petr Resources Res Beijing 100029 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Chinese Acad Sci Innovat Acad Earth Sci Beijing 100029 Peoples R China Res Inst Shaanxi Yanchang Petr Grp Co Ltd Xian 710075 Peoples R China

These effective reservoir rocks that can have sufficient porosity and permeability and hydrocarbon accumulations determine economic reserves and high yield of tight oil and gas. Understanding the origin and distribution of these effective reservoir rocks is important for sorting out "sweet spots" in tight reservoirs. Multiple-scale analyses from the microscopic, via drill core to single wellbore have been conducted to examine reservoir heterogeneity of the Upper Paleozoic Shanxi Formation in the southeastern Ordos Basin. Five sandstone petrofacies have been defined in terms of texture and framework composition, detrital matrix, diagenesis and pore types: quartz arenite, tuffaceous quartz arenite, ductile lithic-lean sub-litharenite, ductile lithic-rich sandstone and tightly carbonate-cemented sandstone. The various petrofacies show fundamentally different pathways of diagenetic and reservoir-quality evolutions, due to the complexity of texture and detrital composition in the Shanxi Formation, directly related to the provenance and depositional environment. Quartz arenites and ductile grain-lean sub-litharenites both form effective reservoir rocks. By translating petrofacies to well-log signatures corrected from petrographic and core analysis data, a model based on factor analysis has been built to predict petrofacies at the well scale. For investigating the distribution of each petrofacies at the field scale, sequential indicator simulation method has been used to construct a 3-d petrofacies model with facies conditioning. The isopach maps of quartz arenites and ductile lithic-lean sub-litharenites have been made from the 3-d petrofacies model to quantify their areal distributions, and to define the "sweet spots" by combining isopach maps of these effective reservoir rocks and gas production data from well tests. The concept of reservoir petrofacies is an important tool for the characterization of tight sandstone reservoirs.

关键词： Reservoir heterogeneity Petrofacies Well log 3-d modeling Tight gas sand

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modeling 3-d Scalar Waves Using the Fourier Finite-difference Method

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Chinese Journal of Geophysics 2013年第6期50卷 1603-1614页

作者： Jin-Hai ZHANG Wei-Min WANG Lian-Feng ZHAO Zhen-Xing YAO

Fourier finite-difference (FFd) operator has both of the advantages of Fourier and finite-difference methods, it can handle the wave propagations in complex media with large velocity contrasts and wide propagation angles. In 3-d case, however, two-way splitting may cause artificial azimuthal anisotropy. In this paper, we handle the remnants of the conventional two-way splitting technique by Fourier transforms, and the azimuthal anisotropy is removed. Based on the dual-domain scheme of the FFd method, the proposed algorithm significantly reduces computational cost caused by error correction. Compared with the finite-difference method by the zero-offset records and shot profiles based on 3-d modified French model, the proposed method can properly model the primary reflected waves and is much more attractive in both computational cost and storage demand.

关键词： 3-d modeling Fourier finite-difference Two-way splitting Wave equation

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A Case of 3-d Small Pile Group modeling in Stiff Clay Under Vertical Loading

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SOILS ANd ROCKS 2015年第1期38卷 67-79页

作者： Freitas, A. C. danziger, B. R. Pacheco, M. P. Univ Fed Rio de Janeiro Setor Geotecnia Dept Construcao Civil BR-21941909 Rio De Janeiro RJ Brazil Univ Estado Rio de Janeiro Dept Estruturas & Fundacoes BR-20550013 Rio De Janeiro RJ Brazil

The behavior of experimental pile groups is simulated by 3-d finite element modeling in this paper. The modeled results are compared to small-scale tests in a row of three closely spaced piles in the London clay. The tests aimed at investigating soil-pile-cap interaction and pile-group effect. It is shown that 3-d FE modeling can be regarded as an appropriate tool to predict settlements and load-transfer mechanisms in pile groups under working conditions, with a satisfactory match between simulated and measured results.

关键词： pile group effect 3-d modeling load transfer settlement prediction

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Morphological characteristics of the cubital tunnel as indication for anterior interosseous nerve supercharge end-to-side transfer in treating advanced cubital tunnel syndrome

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Orthopaedics and Traumatology: Surgery and Research 2025年第3期111卷 103982-103982页

作者： Lee, Jang Won Lee, Sang Ki An, Young Sun Department of Orthopedic Surgery Eulji University College of Medicine Daejeon South Korea

Background: Cubital tunnel syndrome (CuTS) is a prevalent compressive neuropathy addressed through various treatments, including the anterior interosseous nerve (AIN) supercharge end-to-side (SETS) transfer for advanced CuTS. decision to add AIN-SETS is based on various indicators and protocols, but deciding on the appropriate method for borderline cases can be challenging. Therefore, this study aims to non-invasively examine the cubital tunnel anatomy of patients using CT scans and compare the findings with existing indicators and measurements, to determine if they can serve as supplementary indicators to aid in treatment decisions. Hypothesis: The bony cubital tunnel volume is correlated to other traditional indicators and can be used as an additional indication for deciding whether to perform AIN-SETS in treating advanced CuTS. Patients and Methods: This is a single-center retrospective cohort study from South Korea, including 91 patients aged 20–70 years with CuTS. Participants were classified into Group A (n = 43), who underwent both cubital tunnel release (CuTR) and AIN-SETS, and Group B (n = 48), who underwent only CuTR. Preoperative elbow CT data were analyzed for cubital tunnel morphology analysis, with follow-up assessments such as grip strength and electromyography/ nerve conduction velocity (EMG/NCV) tests at 3, 6, and 12 months postoperatively. Results: Group A and B showed no significant differences in demographic parameters, except for a longer disease duration in Group A (p = 0.032). Group A had a smaller cubital tunnel volume (CTV) compared to Group B (1150.6 ± 52.8 mm³ vs. 1173.5 ± 56.2 mm³, p = 0.014) and a smaller cross-sectional area (40.9 ± 10.2 mm² vs. 45.1 ± 11.7 mm², p = 0.033). Pearson correlation analysis revealed statistically significant positive correlations between CTV measurements and pre-operative grip strength, as well as EMG results, a key indicator for AIN-SETS (R² = 0.48, 0.2

关键词： 3-d modeling Anterior interosseous nerve Computed tomography Cubital tunnel syndrome Supercharge end-to-side transfer

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Novel Compression Algorithm Based on Sparse Sampling of 3-d Laser Range Scans

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COMPUTER JOURNAL 2013年第7期56卷 852-870页

作者： dobrucali, Oguzcan Barshan, Billur Bilkent Univ Dept Elect & Elect Engn TR-06800 Ankara Turkey

Three-dimensional models of environments can be very useful and are commonly employed in areas such as robotics, art and architecture, facility management, water management, environmental/industrial/urban planning and documentation. A 3-d model is typically composed of a large number of measurements. When 3-d models of environments need to be transmitted or stored, they should be compressed efficiently to use the capacity of the communication channel or the storage medium effectively. We propose a novel compression technique based on compressive sampling applied to sparse representations of 3-d laser range measurements. The main issue here is finding highly sparse representations of the range measurements, since they do not have such representations in common domains, such as the frequency domain. To solve this problem, we develop a new algorithm to generate sparse innovations between consecutive range measurements acquired while the sensor moves. We compare the sparsity of our innovations with others generated by estimation and filtering. Furthermore, we compare the compression performance of our lossy compression method with widely used lossless and lossy compression techniques. The proposed method offers a small compression ratio and provides a reasonable compromise between the reconstruction error and processing time.

关键词： sensor systems robot sensing systems intelligent sensors compressed sensing data compression compression algorithms 3-d mapping 3-d modeling 3-d laser range measurement laser range finders

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Fusion of range camera and photogrammetry: A systematic procedure for improving 3-d models metric accuracy

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IEEE TRANSACTIONS ON SYSTEMS MAN ANd CYBERNETICS PART B-CYBERNETICS 2003年第4期33卷 667-676页

作者： Guidi, G Beraldin, JA Ciofi, S Atzeni, C Univ Florence Dept Elect & Telecommun I-50139 Florence Italy Natl Res Council Canada Ottawa ON K1A 0R6 Canada

The generation of three-dimensional (3-d) digital models produced by optical technologies in some cases involves metric errors. This happens when small high-resolution 3-d images are assembled together in order to model a large object. In some applications, as for example 3-d modeling of,Cultural Heritage, the problem of metric accuracy is a major issue and no methods are currently available for enhancing it. In this paper the authors present a procedure by which the metric reliability of the 3-d model, obtained through iterative alignments of many range maps, can be guaranteed to a known acceptable level. The goal is the integration of the 3-d range camera system with a close range digital photogrammetry technique. The. basic idea is to generate a global coordinate system, determined by the digital photogrammetric procedure, measuring the spatial coordinates of optical targets placed around the object to be modeled. Such coordinates, set as reference points, allow the proper rigid motion of few key range maps, including a portion of the targets, in the global reference system defined by photogrammetry. The other 3-d images are normally aligned around these locked images with usual iterative algorithms. Experimental results on a anthropomorphic test object, comparing the conventional and the proposed alignment method, are finally reported.

关键词： error analysis measurement accuracy shape measurement 3-d modeling

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