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For today’s demands in underground infrastructure, geotechnical considerations are gaining prominence, emphasizing the resolution of complex problems through numerical modeling and soil-structure interaction analysis. There is a clear trend shifting away from two-dimensional (2-D) plane strain or axisymmetric idealizations to the comprehensive analysis of full three-dimensional (3-D) models. However, despite the inclination towards 3-D modeling of tunnels, establishing a realistic 3-D model for this purpose remains a timeconsuming process. This typically involves multiple iterative and incremental phases, essential for gaining deeper insights into the three-dimensional nature of the problem. Beyond selecting an appropriate constitutive soil model, realistically finite element modeling and accurate simulation of the tunneling process are of paramount importance. This study focuses on the development of a practical full 3-D model and simulation of the Earth Pressure Balance (EPB) shield tunneling process using the finite element code PLAXIS 3D. The numerical model incorporates tunnel boring machine driving data recorded during tunnel construction and is validated through back-analysis of field measurements of tunneling-induced ground surface settlements. The findings demonstrate that numerical simulation can realistically reproduce the main characteristics of EPB shield tunneling. The study recommends adopting non-linear face pressures with depth based on the analysis of tunneling data. Regarding grouting pressure, an effectively linear distributed pressure may be considered, accounting for the grout weight and the increase of soil stresses with depth. This validated numerical framework provides valuable guidance for researchers and practitioners to construct more efficient, reliable, and accurate 3-D models. [ABSTRACT FROM AUTHOR]

Three-dimensional (3-D) liver modeling is used globally; however, its actual practice is limited to a few centers. This study aimed to assess practice patterns and barriers to the use of 3-D modeling among liver surgeons worldwide. A survey approved by the International Hepato-Pancreato-Biliary Association research council consisting of 27 questions was conducted using an online questionnaire. Incomplete responses were excluded. Of 235 respondents from 46 countries, 81.3% reported experience with 3-D modeling; however, only 21% used it in > 75% of cases. Surgeons using 3-D reconstruction were older (P =.025), worked more frequently at academic facilities (P =.007), and had more years of experience (P =.001), especially in minimally invasive liver surgery (MILS) (P =.038). In addition, 3-D rendering was performed by surgeons in 50.8% of cases. Liver volumetry was the most frequent indication (80.1%), and decreased postoperative complications were the main perceived benefit (53.6%). More experience in liver surgery because of seniority, case volume, and openness to novel technology (MILS) is associated with a greater appreciation for the value of 3-D modeling. Our results suggest the need for senior surgeons to help early-career surgeons consider 3-D modeling for the reported benefit of reduced intra- and postoperative complications. [ABSTRACT FROM AUTHOR]

The rock mechanical properties influence the selection of drilling parameters, optimized drilling trajectory, and appropriate hydraulic fracturing intervals. Estimating the 3-D spatial distribution of these geomechanical properties at the reservoir scale is a challenging task, especially in the case of limited data only at the well locations. Advanced geostatistical techniques can be utilized to represent a reservoir's inherent spatial variation more realistically. In this study, we investigate the spatial variability of rock mechanical properties, including Young's modulus, shear modulus, bulk modulus, and Poisson's ratio, as major constituents of the reservoir geomechanical model. The data are extracted from a hydrocarbon field located southwest of Iran and consist of forty wells. We first build a 1-D model of rock elastic moduli at each well by integrating petrophysical and core-based laboratory measurements and then develop a corresponding 3-D model using geostatistical simulation techniques. Thereafter, 3-D seismic data are employed to optimize the geomechanical model. Results show that the integration of well logs with seismic data increases the accuracy of field-wise 3-D elastic moduli models. Furthermore, we used various co-simulation techniques to demonstrate the improving effect of complementary data in constructing a more realistic reservoir geomechanical model. [ABSTRACT FROM AUTHOR]

Heritage sites around the world are being impacted by the climate crisis, a situation that continues to grow in scope and severity. As archaeologists, land managers, and other heritage professionals seek solutions to mitigate the impacts, three-dimensional (3-D) digital heritage techniques can assist heritage professionals in the rapid documentation of sites. This technology can be particularly impactful where sites may be lost, creating a digital record of what the site once was. Building upon its Heritage Monitoring Scouts (HMS Florida) Program, the Florida Public Archaeology Network (FPAN) is using terrestrial laser scanning and photogrammetry to document impacted sites across Florida. Documentation techniques include capturing entire landscapes, as well as curating digital models of artifacts in lieu of collecting the physical objects. Several of its projects, including a study of the techniques during a two-year grant-funded project, shed light on the affordances and constraints of the technology's application in historical archaeology. [ABSTRACT FROM AUTHOR]

Development of chimeric enzymes by protein engineering can more efficiently contribute toward biomass conversion for bioenergy generation. Therefore, prior to experimental validation, a computational approach by modeling and molecular dynamic simulation can assess the structural and functional behavior of chimeric enzymes. In this study, a bifunctional chimera, CtXyn11A-BoGH43A comprising an efficient endoxylanase (CtXyn11A) from Clostridium thermocellum and xylosidase (BoGH43A) from Bacteroides ovatus was computationally designed and its binding and stability analysis with xylooligosaccharides were performed. The modeled chimera showed β-jellyroll fold for CtXyn11A and 5-bladed β-propeller fold for BoGH43A module. Stereo-chemical properties analyzed by Ramachandran plot showed 98.8% residues in allowed region, validating the modeled chimera. The catalytic residues identified by multiple sequence alignment were Glu94 and Glu184 for CtXyn11A and Asp229 and Glu384 for BoGH43A modules. CtXyn11A followed retaining-type, whereas BoGH43A enforced inverting-type of reaction mechanism during xylan hydrolysis as revealed by superposition and GH11 and GH43 familial analyses. Molecular docking studies showed binding energy, (ΔG) − 4.54 and − 4.18 kcal/mol for CtXyn11A and BoGH43A modules of chimera, respectively, with xylobiose, while − 3.94 and − 3.82 kcal/mol for CtXyn11A and BoGH43A modules of chimera, respectively, with xylotriose. MD simulation of CtXyn11A-BoGH43A complexed with xylobiose and xylotriose till 100 ns displayed stability by RMSD, compactness by Rg and conformational stability by SASA analyses. The lowered values of RMSF in active-site residues, Glu94, Glu184, Asp229, Asp335 and Glu384 confirmed the efficient binding of chimera with xylobiose and xylotriose. These results were in agreement with the earlier experimental studies on CtXyn11A releasing xylooligosaccharides from xylan and BoGH43A releasing d-xylose from xylooligosaccharides and xylobiose. The chimera showed stronger affinity in terms of total short-range interaction energy; − 190 and − 121 kJ/mol for with xylobiose and xylotriose, respectively. The bifunctional chimera, CtXyn11A-BoGH43A showed stability and integrity with xylobiose and xylotriose. The designed chimera can be constructed and applied for efficient biomass conversion. [ABSTRACT FROM AUTHOR]

Featured Application: Resource and environmental effects of the Tibetan Plateau. Himalayan orogenesis remains enigmatic in terms of Tibetan Plateau geodynamics originating from the Cenozoic India–Eurasian continental collision. India underthrusts below Tibet to the Yarlung–Tsangpo suture, which has been identified as the northernmost boundary for underplating. However, the way in which the historical evolution of continental subduction induces plateau uplift and the way it controls the variation in uplift between outboard and inboard areas is still unclear. To interpret the evolutionary mechanisms involved in the Himalayan growth history, we constructed different 3-D dynamic models at important stages to address these questions related to the formation of the Himalayas on the basis of paleoenthalpy evidence encoded in fossil leaves from recently documented assemblages in southern Tibet. The results show that (1) the effect of crustal thickening was the predominant factor in the early evolution from the Paleocene to the early Eocene, which resulted in a moderate growth rate. (2) The consecutive slab break-off eastward from the western syntaxis and the associated slab rebound significantly accelerated orogenesis from the late Eocene to the Oligocene. The upwelling asthenospheric flow was a key control of increasing crustal buoyancy, which resulted in the fastest growth of the Himalayas during the early Miocene. (3) Thereafter, the gradually enhanced monsoon and surface erosion during accompanying the increasing mountain height resulted in a slowdown of the orogenic rate, which counterbalanced the buoyant force produced by asthenospheric flow driving continuous Himalayan growth. [ABSTRACT FROM AUTHOR]

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, 0.23, p = 0.01)., Discussion: Measuring the cubital tunnel anatomy using CT can aid in determining the treatment approach for advanced CuTS patients and assist in deciding whether to perform AIN-SETS surgery, serving as a supplementary indicator for cases at the borderline limits of other indicators. Future research may be necessary to establish control groups without symptoms and determine appropriate cut-off values., Level of Evidence: IV., (Copyright © 2024. Published by Elsevier Masson SAS.)

To mitigate the total ionizing dose (TID) radiation impact, a new structure named double-silicon-on-insulator (DSOI) is introduced in this article. This new structure exhibits potential benefits of reducing the radiation-induced degradation effectively and independently, thanks to the additional electrode, which can be used to control the internal electrical field of the device. With this structure, the TID response and TID mitigation strategy using back-bias are discussed in DSOI nMOSFETs. Then, a 3-D TCAD simulation model is proposed to analyze the radiation-induced leakage path for each bias configuration. The impact of negative back-bias during irradiation on trapped charge distribution is given for both buried oxide layer and shallow trench isolation. At last, a 4k-bit static random access memory is used to verify the effectiveness of back-bias on TID-induced leakage current suppression at the circuit level. The experimental results show the possibility of using back-bias against TID threat. [ABSTRACT FROM AUTHOR]

Film shovel is the key device for mechanized operation of residual film recovery, in which the depth of soil breakage of the shovel is related to the degree of damage to the plastic film and the recovery efficiency of the residual film. However, the current mode of operation requires experience and visual inspection, which often leads to low level of mechanization and inefficient operation. The topic is to improve the existing residual film recovery device, focusing on the three-dimensional modeling and monitoring system of intelligent film lifting shovel. By optimizing the three-dimensional structure of the intelligent film-lifting shovel and kinematics simulation analysis based on Adams software, the design inclination angle of the loosening shovel is 60 ∘ , and the breaking depth of the safe operation is 20–50 mm. Then through the use of Ethernet interface based on EtherCAT bus and the real-time bidirectional communication between BECKHOFF CX2030 controller and module and HMI, the on-line data transmission in the process of intelligent film shovel operation is realized. Field test results verify that the intelligent film-lifting shovel is feasible in the intelligent operation and recovery efficiency of the residual film recovery operation, which can greatly improve the efficiency of the whole machine operation. [ABSTRACT FROM AUTHOR]

A 3D model for a section of cathode fuel cell comprised of a bipolar plate, a gas diffusion layer (GDL) and a catalyst layer was simulated. The diameter of the carbon fiber GDL is assumed to be the same; moreover, a new and simple method is introduced for the reconstruction of this layer numerically. This method gives the ability to model the heterogeneous and anisotropic structure of the GDL; furthermore, it allows easy implementation and provides realistic results with consideration of the lack of overlap between carbon fibers. The lattice Boltzmann method (LBM) was employed to simulate the flow and the electrochemical reaction. The impacts of changes in the activation potential and the GDL carbon fiber diameter on oxygen species and water vapor, as well as the electric current density distribution over the catalyst layer, were studied. The results showed that at higher values of the activation potential, the concentration of oxygen near the catalyst layer was lower. The current density over the catalyst layer also increased by increasing the activation potential; on the other hand, the mole fraction of water vapor in the cathode increased with the increase in the flow of gas products. Consequently, results indicated that the variation in the GDL carbon fiber diameter affects the distribution of reactants. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Himalayan orogenesis remains enigmatic in terms of Tibetan Plateau geodynamics originating from the Cenozoic India–Eurasian continental collision. India underthrusts below Tibet to the Yarlung–Tsangpo suture, which has been identified as the northernmost boundary for underplating. However, the way in which the historical evolution of continental subduction induces plateau uplift and the way it controls the variation in uplift between outboard and inboard areas is still unclear. To interpret the evolutionary mechanisms involved in the Himalayan growth history, we constructed different 3-D dynamic models at important stages to address these questions related to the formation of the Himalayas on the basis of paleoenthalpy evidence encoded in fossil leaves from recently documented assemblages in southern Tibet. The results show that (1) the effect of crustal thickening was the predominant factor in the early evolution from the Paleocene to the early Eocene, which resulted in a moderate growth rate. (2) The consecutive slab break-off eastward from the western syntaxis and the associated slab rebound significantly accelerated orogenesis from the late Eocene to the Oligocene. The upwelling asthenospheric flow was a key control of increasing crustal buoyancy, which resulted in the fastest growth of the Himalayas during the early Miocene. (3) Thereafter, the gradually enhanced monsoon and surface erosion during accompanying the increasing mountain height resulted in a slowdown of the orogenic rate, which counterbalanced the buoyant force produced by asthenospheric flow driving continuous Himalayan growth.

We estimated the seismic attenuation (Q factor) of the Greenland Ice Sheet (GrIS) by comparing observed and theoretical Rayleigh waveforms. Observed waveforms are obtained by interfering noise waveforms in vertical‐component seismograms between stations belonging to the latest broadband seismic network distributed throughout Greenland (GLISN network). Theoretical waveforms are calculated by parallel computation using the latest 3‐D seismic waveform modeling method. Comparing the observed waveforms with the theoretical waveforms at different Q factors reveals that the GrIS has a low Q of 10 ≤ QP, QS ≤ 50, indicating very high attenuation of seismic waves due to the ice. This study is the first to establish the low Q factor of ice sheets via ultra‐long‐distance propagation (350−1,000 km). The Q factors obtained in this study are indispensable for estimating the thermal state and density distribution of the GrIS, as well as for interpreting the characteristics of seismic waveform that propagates through the GrIS. Plain Language Summary: Seismic anelastic attenuation refers to the energy loss caused by anelastic processes or internal friction during wave propagation and is quantified by the quality (Q) factor. The Q factor of ice sheets and glacial ice is especially important because it is highly sensitive to the thermal state and density distribution. We estimated the Q factor of the Greenland Ice Sheet (GrIS) by comparing observed and theoretical surface (Rayleigh) waveforms. Observed waveforms are extracted by the latest broadband seismic network distributed throughout Greenland (GLISN network). Theoretical waveforms are calculated using the latest 3‐D seismic waveform modeling method. The results showed an extremely low Q (10–50) for the GrIS, indicating very high attenuation of seismic waves. Although previous studies have obtained similar results, they all used high frequency (≥30 Hz) seismic waves with short propagation distances (<∼10 km). This study is the first to infer the large‐scale, bulk Q property of the GrIS using low‐frequency (0.1–0.3 Hz) waves and long (350−1,000 km) propagation distances. The Q factors obtained in this study are essential for estimating the internal state of the GrIS, as well as for interpreting the characteristics of seismic waveforms that propagate through it. Key Points: Seismic attenuation of the Greenland Ice Sheet is estimated by comparing the observed and theoretical Rayleigh waveformsThe quality (Q) factor of the ice sheet is 10–50 for both P and S waves, indicating extremely high attenuationThis is the first Q estimation targeting the ice sheet using waves with a propagation distance of more than 100 km [ABSTRACT FROM AUTHOR]

The blue carbon ecosystem, including the salt marsh ecosystem, possesses a significant carbon sequestration potential. Therefore, accurately quantifying the carbon storage within such ecosystems is crucial for the adequate accounting of carbon sequestration. The present work chose a Spartina alterniflora ecosystem in the Xiaogan Island (China) as the study area (approximately 11 ha), and employed the Bayesian maximum entropy (BME) approach to assimilate both hard organic carbon (OC) data and soft OC data measured from 2 cm and 10 cm stratified samples. A 3-dimensional model was developed for space-time OC estimation purposes based on the sediment chronology results. The 10-fold BME cross validation results demonstrated a high estimation accuracy, with the R2, RMSE and MAE values equal to 0.8564, 0.1026 % and 0.0748 %, respectively. A noteworthy outcome was the BME-generated carbon storage density maps with 1 m spatial resolution. These maps revealed that the carbon storage density at the top 30 cm sediment depth in the stable zone (with elder stand age of S. alterniflora) was higher than that in the rapid expansion zone, i.e., 71.79 t/ha vs. 69.82 t/ha, respectively. Additionally, the study found that the averaged carbon burial rate and the total carbon storage at the top 30 cm sediment depth across the study area were 266 g C/m2/yr and 781.50 t, respectively. Lastly, the proposed BME-based framework of carbon storage estimation was found to be versatile and applicable to other blue carbon ecosystems. This approach can foster the development of a standardized carbon sink metrological methodology for diverse blue carbon ecosystems. • Carbon storage in salt marsh ecosystem was estimated at a spatial resolution of 1 m. • BME exhibited versatile ability for carbon storage estimation in a space-time domain. • Stand age of Spartina Alterniflora positively related to the carbon storage in sediment. [ABSTRACT FROM AUTHOR]

Abstract Determining the width of an induced hydraulic fracture is the first step for applying wellbore strengthening and hydraulic fracturing techniques. However, current 2-D analytical solutions obtained from the plane strain assumption may have large uncertainties when the fracture height is small. To solve this problem, a 3-D finite element method (FEM) is used to model wellbore strengthening and calculate the fracture width. Comparisons show that the 2-D plane strain solution is the asymptote of the 3-D FEM solution. Therefore, the 2-D solution may overestimate the fracture width. This indicates that the 2-D solution may not be applicable in 3-D conditions. Based on the FEM modeling, a new 3-D semi-analytical solution for determining the fracture width is proposed, which accounts for the effects of 3-D fracture dimensions, stress anisotropy and borehole inclination. Compared to the 2-D solution, this new 3-D semi-analytical solution predicts a smaller fracture width. This implies that the 2-D-based old design for wellbore strengthening may overestimate the fracture width, which can be reduced using the proposed 3-D solution. It also allows an easy way to calculate the fracture width in complex geometrical and geological conditions. This solution has been verified against 3-D finite element calculations for field applications.

Façade features are important in large-scale level-of-detail 3 (LoD-3) reconstruction in urban environments, and street-view panoramas are arguably the best option for detailed 3-D façade modeling. However, despite the plethora of street-view panoramas available, few studies have explored the metric capabilities of panoramas. This is due in part to the complexities of system integration and in part to problems associated with projection (e.g., distortion at the tops of buildings), and deformation (e.g., the bending of straight structures). In an effort to solve these problems, this letter introduces a flexible and practical solution using only a single panorama. The key is to efficiently rectify panoramas using image-space line constrained deformation inspired by the as-rigid-as-possible deformation of surface meshes. The image is then re-projected using gnomonic projection on a properly selected tangent plane. The proposed approach requires a reasonable amount of user interaction to select and position the vertical line segments. The tangent point is also chosen empirically for each panorama. The rectified images can then be imported into off-the-shelf 3-D modeling solutions as reference images for interactive sketching. Experimental evaluations reveal the effectiveness of the image-space rectification: after proper scaling, the semantic-aware 3-D façade models achieve decimeter-level accuracy with respect to the reference surface mesh. [ABSTRACT FROM AUTHOR]

We explore dense water cascading (DWC), a type of bottom‐trapped gravity current, on multidecadal time scales using a pan‐Arctic regional ocean‐ice model. DWC is particularly important in the Arctic Ocean as the main mechanism of ventilation of interior waters when open ocean convection is blocked by strong density stratification. We identify the locations where the most intense DWC events occur and evaluate the associated cross‐shelf mass, heat, and salt fluxes. We find that the modeled locations of cascading agree well with the sparse historical observations and that cascading is the dominant process responsible for cross‐shelf exchange in the boundary layers. Simulated DWC fluxes of 1.3 Sv (1 Sv = 106 m3/s) in the Central Arctic are comparable to Bering Strait inflow, with associated surface and benthic Ekman fluxes of 0.85 and 0.58 Sv. With ice decline, both surface Ekman flux and DWC fluxes are increasing at a rate of 0.023 and 0.0175 Sv/year, respectively. A detailed analysis of specific cascading sites around the Beaufort Gyre and adjacent regions shows that autumn upwelling of warm and saltier Atlantic waters on the shelf and subsequent cooling and mixing of uplifted waters trigger the cascading on the West Chukchi Sea shelf break. Lagrangian particle tracking of low salinity Pacific waters originating at the surface in the Bering Strait shows that these waters are modified by brine rejection and cooling, and through subsequent mixing become dense enough to reach depths of 160–200 m.Plain Language Summary: In this study we explore dense water cascading, а specific type of bottom‐trapped gravity current. This current of very dense waters originates on the shelves, due to winter cooling and sea ice freezing, and slowly propagates downslope to deep waters. It is specifically important in the Arctic Ocean as the main mechanism of deep water mass formation and carbon storage. We use numerical model of the Arctic Ocean to predict preferable locations of the cascading, its intensity mass, and heat fluxes. Our results are in agreement with available very sparse observations. Our model predicts that with sea ice melting, cascading formation will accelerate.Key Points: Dense water cascading is explored on multidecadal time scales in a 3‐D pan‐Arctic model, presenting good agreement with observationsThe cross‐shelf water exchanges caused by cascading are estimated as 1.3 Sv of volume flux, thus exceeding the Bering Strait inflowUpwelling of Atlantic waters onto the shelf, followed by subsequent cooling and mixing, trigger cascading on the West Chukchi Sea shelf [ABSTRACT FROM AUTHOR]

Delineating the boundary between troposphere and stratosphere in a chemistry transport model requires a state variable for each air mass that maps out the ever shifting, overlapping three-dimensional (3-D) boundary at each time step. Using an artificial tracer, e90, with surface sources and 90 day decay time, the model e90 tropopause matches the 1-D temperature lapse rate definition of the tropopause as well as the seasonal variation of ozone at this boundary. This approach works from equator to pole, over all seasons, unlike methods based on potential vorticity or ozone. By focusing on the time scales that separate stratosphere from troposphere, we examine the cause of ozone seasonality at the midlatitude tropopause, the oldest air in the troposphere (winter descent in the subtropics), and a north-south bias in the age of air of the lowermost stratosphere as evaluated using a northern tracer. The tracer e90 is invaluable in 3-D modeling, readily separating stratosphere from troposphere and a giving quantitative measure of the effective distance from the tropopause.

We show that high‐resolution aeromagnetic surveys, although rarely employed in the research of salt structures, may be an effective and low‐cost tool for mapping diapirism. A multiscale analysis of a high‐resolution magnetic data set at Nordkapp Basin in the Barents Sea, allows a clear reconstruction of the main salt diapirs of the basin using Multiridge and Compact Depth from Extreme Points methods. We provide a 3‐D model of the diapirs extended from 500 to 4,000 m below sea level, characterized by a general low magnetization contrast no larger than −0.08 A/m. The 3‐D model is consistent with the salt top depth estimated by 2‐D seismics, with borehole data and with the 2‐D gravity model of the Uranus diapir. Our imaging shows the capability of the magnetic method that gives new and comprehensive pictures of salt diapirism. Key Points: We interpret the magnetic field of the Nordkapp Basin by a multiscale approachImaging methods applied to magnetic data can well identify the top, bottom, and shape of saline structuresHigh‐resolution aeromagnetic surveys are a valid and low‐cost tool for mapping diapirism where other methods are not entirely effective [ABSTRACT FROM AUTHOR]

Contribution: The NEWTON fabrication laboratory (Fab Lab) Education Initiative assesses the effectiveness of Fab Lab-based learning on K–12 students’ attitude toward learning science, technology, engineering, art, and mathematics (STEAM). It considers two aspects: 1) students’ motivation and affective state and 2) students’ observations and perception of Fab Lab-based learning. Background: Fab Labs are described as small workshops equipped with a set of computer-controlled tools (e.g., 3-D printers) that offer personalized digital fabrication. They have been shown to have a positive impact on learners’ academic and personal growth when used in extracurricular activities, but little research examines whether integrating Fab Labs into school curricula can help raise student interest in STEAM education. Research Question: Can Fab Lab-based learning foster students’ interest in STEM in primary and secondary schools? Would students be keen to use Fab Labs in their science classes? Methodology: Two case studies were carried out in two different schools as part of the European Horizon 2020 NEWTON project. The study had 39 participants; three different surveys were used to assess different constructs. Findings: Results show that after using the Fab Lab-based learning: 1) students felt more interested in science classes as well as more engaged and less bored and 2) while some students struggled at first when manipulating Fab Lab tools, they adapted quickly and reported that they would like to use Fab Labs as part of their science classes. [ABSTRACT FROM AUTHOR]

The Fairfield Foundation is using new technology to record and recreate archaeology at Fairfield Plantation. Using drone-based photogrammetry, Autodesk 3-D modeling software, and a MakerBot 3-D printer, the organization is developing three-dimensional models of every stratigraphic layer excavated, then printing replicas of each layer that connect seamlessly. This interactive model of the site is ideal for teaching students and the public about archaeology while engaging them in the history and architecture of Fairfield Plantation. At the same time, it creates the most detailed archive of archaeological data yet undertaken at this site, providing the foundations for future virtual and augmented reality applications and preserving a vital record of the archaeology. Methods developed for this project can be applied at any site, enhancing outreach and site documentation efforts around the world, especially when initiated at the onset of a project. [ABSTRACT FROM AUTHOR]

Wideband electromagnetic induction sensors have been shown to be more effective than traditional metal detectors at identifying metallic targets of interest when buried near abundant metallic clutter. A promising strategy for performing target identification using wideband data relies on characterizing the target response using a magnetic polarizability tensor (MPT) that is a function of frequency. In this paper, a surface integral method is presented for deriving the MPT in singularity expansion form using a modal decomposition. The method is verified by comparing the singularity expansion for a spherical shell to a derived analytical solution. The expansion coefficients for cylindrical tubes, of various aspect ratios, are compared to experimental results, showing good agreement. Finally, expansion coefficients are given for a disk and are compared to other numerical results. [ABSTRACT FROM AUTHOR]

In this study, thermal performance and flow characteristics of a shell and tube heat exchanger equipped with various baffle angles were studied. The heat exchanger was operated with distilled water, and a hybrid nanofluid at three concentrations of 0.04% and 0.10% of GNP-Ag/water within Reynolds numbers ranged between 10,000 and 20,000. The thermophysical properties of nanofluid varied with temperature and nanoparticles’ concentration. The baffle angles were set at 45°, 90°, 135°, and 180°. Results showed that the calculated Nusselt number (Nu) could be improved by adding nanoparticles to the distilled water or increasing the fluid’s Reynolds number. At a low Re number, the Nu corresponding to baffle angle of 135° was very close to that recorded for the angle of 180°. At Re = 20,000, the Nu number was the highest (by 35% compared to the reference case), belonging to a baffle angle of 135°. Additionally, results related to friction factor and pressure drop showed that more locations with fluid blocking were observed by increasing the baffle angle, resulting in increased pressure drop value and friction. Finally, the temperature streamlines counter showed that the best baffle angle could be 135° in which maximum heat removal and the best thermal performance can be observed.

Determining the width of an induced hydraulic fracture is the first step for applying wellbore strengthening and hydraulic fracturing techniques. However, current 2-D analytical solutions obtained from the plane strain assumption may have large uncertainties when the fracture height is small. To solve this problem, a 3-D finite element method (FEM) is used to model wellbore strengthening and calculate the fracture width. Comparisons show that the 2-D plane strain solution is the asymptote of the 3-D FEM solution. Therefore, the 2-D solution may overestimate the fracture width. This indicates that the 2-D solution may not be applicable in 3-D conditions. Based on the FEM modeling, a new 3-D semi-analytical solution for determining the fracture width is proposed, which accounts for the effects of 3-D fracture dimensions, stress anisotropy and borehole inclination. Compared to the 2-D solution, this new 3-D semi-analytical solution predicts a smaller fracture width. This implies that the 2-D-based old design for wellbore strengthening may overestimate the fracture width, which can be reduced using the proposed 3-D solution. It also allows an easy way to calculate the fracture width in complex geometrical and geological conditions. This solution has been verified against 3-D finite element calculations for field applications. [ABSTRACT FROM AUTHOR]

Mixing in the ocean and shelf seas is critical for the vertical distribution of dynamically active properties, such as density and biogeochemical tracers. Eight different decadal simulations are used to assess the skill of vertical turbulent mixing schemes (TMS) in a 3‐D regional model of tidally active shelf seas. The TMS differ in the type of stability functions used and in the Ozmidov/Deardorff/Galperin limiter of the turbulence length scales. We review the dependence of the critical Richardson and Prandtl numbers to define the "diffusiveness" of the TMS. The skill in representing bias and variability of stratification profiles is assessed with five different metrics: surface and bottom temperatures and pycnocline depth, thickness, and strength. The assessment is made against hydrography from three data sets (28,000 profiles in total). Bottom and surface temperatures are found to be as sensitive to TMS choice as to horizontal resolution or heat flux formulation, as reported in other studies. All TMS underrepresent the pycnocline depth and benthic temperatures. This suggests physical processes are missing from the model, and these are discussed. Different TMSs show the best results for different metrics, and there is no outright winner. Simulations coupled with an ecosystem model show the choice of TMS strongly affects the ecosystem behavior: shifting the timing of peak chlorophyll by 1 month, showing regional chlorophyll differences of order 100%, and redistributing the production of chorophyll between the pycnocline and mixed layer. Key Points: Turbulence closures are assessed in 3‐D simulations in tidally energetic environmentIn the shelf seas, all closures simulate a seasonal pycnocline that is too shallow and bottom temperatures that are too warm; there is no clear winner out of the choice of closuresChoice of turbulence closure affects the ecosystem behavior, shifting the timing of peak chlorophyll by 1 month and regional chlorophyll differences of order 100% [ABSTRACT FROM AUTHOR]

Creating the initial geometry and temperature configuration of 3‐D numerical simulations is a challenging task. Professional tools are expensive. They often have a steep learning curve and do mostly not interface with the numerical simulation software used by the geodynamics and tectonics academic community. There, we developed geometry Input/Output (geomIO), a MATLAB toolbox to create the initial configuration of geological models regarding model geometry and temperature structure. geomIO allows users to create a geo‐referenced 3‐D volume by drawing multiple 2‐D cross sections in a standard vector graphics editor. The volume is then used to assign material properties and set up initial temperature distribution on a set of vertices. In 2‐D mode, polygons can also be used to create a triangular mesh. In addition to the standard functionality, the gravity anomaly of any geometry created with geomIO can be calculated. In this paper, we give an overview of the basic functionalities of geomIO. We illustrate the strength of our software with advanced tectonic and geodynamic applications that could not have been performed with currently available free software. Applications include the Himalayan orogen, the Japanese subduction zones, present‐day salt diapirs, and small‐scale tectonic structures. We describe algorithms and file formats in the supporting information. The toolbox is user‐friendly and flexible. Users can use custom pipelines or preset data processing pipelines, so most applications require only a few lines of code. geomIO is distributed under the GNU General Public License and includes an online wiki with tutorials and additional examples. Plain Language Summary: Numerical methods are often used to simulate complex physical processes like the deformation of materials. However, creating the initial geometry and temperature configuration of three‐dimensional (3‐D) numerical simulations is a challenging task. Professional tools are expensive, have a high learning curve, and do not interface with the numerical simulation software used by the geologic academic community. Therefore, we developed geometry Input/Output (geomIO). geomIO is a software to create the geometry and initial temperature distribution of numerical simulations. geomIO allows the user to create a 3‐D volume by drawing multiple 2‐D cross sections in a vector graphics editor. Various physical properties are then attributed to this volume. In this paper, we give an overview of the basic functionalities of geomIO and some examples of advanced applications to geological problems. These applications include the Himalayan orogen, the Japanese subduction zones, present‐day salt domes, and small‐scale tectonic structures. The toolbox is user‐friendly and flexible. It allows users to create custom data treatment and with preset options, such that most applications require only a few lines of code. geomIO is distributed under the GNU General Public License, and it includes an online tutorial with additional examples. Key Points: geomIO is an open‐source MATLAB toolbox to design the initial geometry/temperature of 2‐D/3‐D numerical simulations from 2‐D vector graphicsWe demonstrate advanced applications to geodynamic problemsThe online repository contains tutorials and examples to perform basic and advanced tasks [ABSTRACT FROM AUTHOR]

Abstract 3-D inversion of geophysical data has become a practical, commonly used tool in the interpretation of magnetotelluric (MT) data. However, 3-D inversion is a non-linear and non-unique task and requires adopting additional assumptions. In this paper, we analyze the influence of selection of inversion parameters in the case of previously published, real model for Pomerania region (Poland). This zone is a regional scale 2-D structure, which locally becomes 3-D. The analyzed model was accomplished by inversion of full impedance and tippers from 31 MT stations with the period range from 10 s to 10,000 s. The inversion parameters were chosen to provide the best possible agreement of the model with well-known geophysical and geophysical data. The purpose of the presented work is to determine how the change of some inversion parameters influences previously obtained model, and therefore we check which structure features remain in spite of the change of the implied parameters. A number of tests were performed employing an implementation of the freely available ModEM inversion package. These included the choice of an appropriate initial model and a model covariances evaluation as a means to control smoothness between adjoining model areas. Additionally, we compared the models calculated from all transfer functions (impedances and tippers) and from subsets (only tippers and off-diagonal components of the impedance tensor and tippers). Moreover, the tests with the model coordinate system rotation were performed. Our analysis has shown that the values of covariance matrix coefficients have an evident effect on the results. However, the multiple use of the covariance matrix with small coefficients gives a similar result as its single use with higher coefficients. The initial model and the selection of the transfer function for inversion can significantly change the model. However, changing the orientation of the coordinate system from geographic to the one that is aligned with a regional strike direction does not cause noticeable changes in the solution obtained. It can be only noted that for the rotated coordinate system the obtained model becomes closer to the model of a 2-D regional structure. Highlights • 3-D inversion of different magnetotelluric real data sets with various model parameterizations • Examination of the choice of MT transfer functions set on the 3-D inversion solution. • Our tests prove the necessity of careful and appropriate selection of inversion parameters, model space, and type of transfer functions [ABSTRACT FROM AUTHOR]

The creation of digital repositories of human skeletal remains offers bioarchaeologists a variety of potential means of aiding efforts related to curation and analysis. We present a discussion of how issues of preservation and access can affect research and argue that digital repositories not only maintain a record of objects but that the digital format allows researchers to expand their studies to include otherwise inaccessible collections. Digital models can be utilized by bioarchaeologists to collect and analyze a wide variety of quantitative and qualitative data. We review several digital capture methods employed by bioarchaeologists, including CT scanning, laser scanning, and photogrammetry. While photogrammetry is underutilized by bioarchaeologists, we point out its many advantages over other methods. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is going through rapid reorganization due to anthropogenic influences. Understanding how biogeochemical transformation and erosion‐induced SOC redistribution influence SOC profiles and stocks is critical to our food security and adaptation to climate change. The important roles of erosion and deposition on SOC dynamics have drawn increasing attention in the past decades, but quantifying such dynamics is still challenging. Here we develop a process‐based quasi 3‐D model that couples surface runoff, soil moisture dynamics, biogeochemical transformation, and landscape evolution. We apply this model to a subcatchment in Iowa to understand how natural forcing and farming practices affect the SOC dynamics in the critical zone. The net soil thickness and SOC stock change rates are −0.336 (mm/yr) and −1.9 (g C/m2/year), respectively. Our model shows that in a fast transport landscape, SOC transport is the dominant control on SOC dynamics compared to biogeochemical transformation. The SOC profiles have "noses" below the surface at depositional sites, which are consistent with cores sampled at the same site. Generally, erosional sites are local net atmospheric carbon sinks and vice versa for depositional sites, but exceptions exist as seen in the simulation results. Furthermore, the mechanical soil mixing arising from tillage enhances SOC stock at erosional sites and reduces it at depositional ones. This study not only helps us understand the evolution of SOC stock and profiles in a watershed but can also serve as an instrument to develop practical means for protecting carbon loss due to human activities. Plain Language Summary: Understanding how soil organic carbon (SOC) content changes in space and time are critical for our food security and adaptation to climate change. It changes through the belowground transformation—decomposition of litter and release of CO2, and surficial transport—lateral physical redistribution. The balance between the two interactions has been strongly shifted by human activities. Quantifying such interactions has remained challenging. Here we developed a 3‐D model, which simulates the movement and burial of SOC and compare the impacts of natural and human activities in the critical zone. We apply this model to a watershed in Iowa. Our results show that the net soil thickness and SOC stock change rates are both decreasing. The fast burial of legacy carbon by modern carbon results in a "nose" profile at depositional sites, which is consistent with soil cores sampled in the watershed. The lateral transport rate can be significantly larger than the transformation rate, but this balance is modified by the mechanical mixing from tillage. Generally, erosional sites are net sinks for atmospheric carbon and depositional sites are net sources. The model can serve as an important tool for protecting soil carbon change caused by both human and natural events. Key Points: A process‐based 3‐D model is developed to simulate the coevolution of soil organic carbon (SOC) and landscape in a watershedVertical SOC profiles evolve heterogeneously across the watershed due to SOC redistribution and biogeochemical transformationGenerally, erosion and deposition sites are local net atmospheric C sinks and sources, respectively, but exceptions exist [ABSTRACT FROM AUTHOR]

Geomagnetically induced currents (GICs) flowing in long conductors can pose a threat to critical infrastructure such as the power grid in cases of extreme geomagnetic activity. Geomagnetic activity is more pronounced at high latitudes; thus, Nordic countries, such as Sweden, can potentially be vulnerable to GIC. Previous studies have identified the southern region of Sweden as the most vulnerable to extreme space weather, but these studies have relied on 1‐D models of the ground conductivity. Sweden, however, has large lateral variations in the underlying ground conductivity structure across the country. Thus, the understanding of the ground response to space weather events cannot be captured by 1‐D models. In this paper, we utilize a 3‐D crustal conductivity map with surrounding oceans to model the geoelectric ground response due to a uniform magnetic field. We show that southern Sweden is exposed to stronger electric fields due to a combined effect of a low crustal conductivity and the influence of the coast‐land interface from both the east and the west coast. The model can further be used to calculate GICs in the Swedish power grid and has been validated by GIC measurements from a site in northern Sweden. The measured and predicted GIC amplitudes are in excellent agreement. The model can be used to quantitatively asses the hazard from space weather in Sweden. Upon further validation at additional sites it can be used as a powerful predictive tool of the response to extreme space weather events in the Swedish power network. Key Points: Three‐dimensional modeling of the geoelectric field in Sweden is performed based on a crustal conductivity map for the Fennoscandinavian shieldSouthern Sweden is exposed to stronger electric fields due to a combined effect of a lower crustal conductivity and the coastal effectGICs calculated based on the 3‐D modeling, nearby magnetic field observations, and a power grid model are verified by measured GICs [ABSTRACT FROM AUTHOR]

A farm owner was found unresponsive with crushing head injuries on his property in rural Ontario. His small farm tractor was found 60 meters away down a small incline with the engine running and transmission in neutral. The owner's son alleged that when the parking brake was engaged (with the engine running and transmission in neutral), this tractor's parking brake would "pop out," allowing the tractor to move. Field tests were conducted on the tractor to attempt to duplicate the scenario and to determine if the alleged sequence of events was plausible. Components of the parking brake and one exemplar were assessed with specialized metrology to determine whether they were within the manufacturing specifications on the blueprint. A 3-D CAD model of fit was created, and several variances were identified between the parts and the factory drawing. The results of the analysis concurred with the scenario that these variances led to the disengagement of the parking brake and operator fatality. [ABSTRACT FROM AUTHOR]

Understanding of the potential to injection‐induced seismicity along faults requires the response of fault zone system to spatiotemporal perturbations in pore pressure and stress. In this study, three‐dimensional (3‐D) model system consisting of the caprock, reservoir, and basement is intersected by vertical strike‐slip faults. We examine the full poroelastic behavior of the formation and perform the mechanical analysis along each fault zone using the Coulomb stress change. The magnitude, rate, and location of potential earthquakes are predicted using the spatial distribution of stresses and pore pressure over time. Rapid diffusion of pore pressure into conductive faults initiates failure, but the majority of induced seismicity occurs at deep fault zones due to poroelastic stabilization near the injection interval. Less permeable faults can be destabilized by either delayed pore pressure diffusion or poroelastic stressing. A two‐dimensional (2‐D) horizontal model, representing the interface between the reservoir and the basement, limits diffusion of pore pressure and deformation of the formation in the vertical direction that may overestimate or underestimate the potential of earthquakes along the fault. Our numerical results suggest that the 3‐D modeling of faulting system including poroelastic coupling can reduce the uncertainty in the seismic hazard prediction by considering the hydraulic and mechanical interaction between faults and bounding formations. Key Points: Multiple faulting system is modeled in a three‐dimensional (3‐D) domain, including poroelastic couplingPore pressure diffusion and/or poroelastic stressing induce seismicity along the fault with any hydraulic typeThe 3‐D modeling captures properly the hydraulic and mechanical interaction between faults and surrounding formations [ABSTRACT FROM AUTHOR]

Surface nuclear magnetic resonance (SNMR) technique has been widely applied to noninvasive groundwater exploration and aquifer quantitative characterization. Furthermore, it has the potential for studying and detecting hydrocarbon contaminants and for water resource management. To increase the tomography resolution of groundwater and expand the application range of SNMR, we first implemented its 3-D forward modeling using a vector finite-element (FE) method based on the total electric field. The key of SNMR forward modeling is the calculation of excitation magnetic field, and the total-field algorithm is an alternative scheme to numerically simulate the electromagnetic field. In this paper, we viewed the circular loop source as the combination of a certain number of horizontal electric dipoles. The unstructured tetrahedral mesh and local refinement technology were combined to precisely delineate the distribution of circular loop source, which effectively reduces the adverse effects of field source singularity. Then, the vector FE solver based on the total electric field was used to calculate the magnetic field distribution. The accuracy of the calculated results was validated by the analytical solutions for a circular loop laid on the surface of a homogeneous half-space. After calculating the excitation field, SNMR responses of three typical synthetic 3-D groundwater models were obtained with the basic signal response formula. Finally, we studied the effects of some important factors which have significant influences on SNMR signal responses and have practical importance in groundwater issues. [ABSTRACT FROM AUTHOR]

High-strength steel suffers from an increasing susceptibility to solidification cracking in welding due to increasing carbon equivalents. However, the cracking mechanism is not fully clear for a confidently completely crack-free welding process. To present a full, direct knowledge of fracture behavior in high-strength steel welding, a three-dimensional (3-D) modeling method is developed using the extended finite element method (XFEM). The XFEM model and fracture loads are linked with the full model and the output of the thermo-mechanical finite element method (TM-FEM), respectively. Solidification cracks in welds are predicted to initiate at the upper tip at the current cross-section, propagate upward to and then through the upper weld surface, thereby propagating the lower crack tip down to the bottom until the final failure. This behavior indicates that solidification cracking is preferred on the upper weld surface, which has higher weld stress introduced by thermal contraction and solidification shrinkage. The modeling results show good agreement with the solidification crack fractography and in situ observations. Further XFEM results show that the initial defects that exhibit higher susceptibility to solidification cracking are those that are vertical to the weld plate plane, open to the current cross-section and concentratedly distributed compared to tilted, closed and dispersedly distributed ones, respectively.

In the context of a 10-day summer camp makerspace experience that employed design-based learning (DBL) strategies, the purpose of this descriptive case study was to better understand the ways in which children use visualization skills to negotiate design as they move back and forth between the world of nondigital design techniques (i.e., drawing, 3-D drawing with hot glue, sculpture, discussion, writing) and digital technologies (i.e., 3-D scanning, 3-D modeling, 3-D printing). Participants included 20 children aged 6-12. This research was guided by Vossoughi, Hooper, and Escudé's (2016) call for explicit attention to pedagogical practices during the integration of "making" activities. Content analysis was used to analyze qualitative data, including observation, researcher/facilitator field notes, think aloud protocols, daily reflective exit tickets, and participant artifacts. Findings highlight the ways in which participants negotiated visualization skills through (a) imagining, drawing, and seeing through creating 2-D sketches, (b) reasoning and relating through writing stories, (c) transforming through 3-D extrusion, (d) observing and noticing through 3-D sculpting and 3-D scanning, and (e) manipulating through digital 3-D modeling, mental rotation, and mental transformation. Implications for formal K-12 educational contexts and teacher preparation programs are discussed. [ABSTRACT FROM AUTHOR]

Functionality of an infrastructure is its ability to provide its intended services. Maintaining an acceptable level of infrastructure functionality, particularly for critical infrastructure, following an extreme event is vital for effective community recovery. Estimating functionality depends on proper quantification of losses, which requires accurate assessment of infrastructure damage. The damage is presented in the form of fragility functions that are generally developed using nonlinear finite element analysis. To date, no study has been conducted to assess the effect of modeling approach on seismic fragilities of an infrastructure, the associated losses, and functionality reduction. In addition, existing frameworks for estimating functionality of critical infrastructure, such as a hospital, following an extreme event have not considered the interdependent relationship between a hospital and other lifelines. In this study, a new framework for evaluating immediate functionality of a hospital following an earthquake is presented. The functionality is estimated based on hospital losses that result from its sustained damage as well as damage to other lifelines on which the hospital relies. In addition, the effects of modeling resolution on the calculated fragilities, the estimated direct losses, and the associated functionality are evaluated. The hospital models vary from simplified 2-D with idealized boundary conditions to more comprehensive 3-D models that account for soil-structure interaction. The analysis show that using simplified 2-D models that ignore soil-structure interaction could lead to non-conservative results. On the contrary, using more refined 3-D models could provide accurate estimation of the behavior, and subsequently better assessment of losses and functionality. [ABSTRACT FROM AUTHOR]

X-ray tomography is used to produce three-dimensional images of an aluminium alloy foam with a high porosity ( > 93 % ). These data allow describing the foam structure from which a finite element model is derived to predict the thermal conductivity of the foam. The results are compared with experimental values measured by a new guarded hot plate apparatus adapted for the range of thermal conductivity values of interest. Good agreement is observed which validated the finite element model used to evaluate the thermal properties of any porous metallic foam with stochastic cell size and configuration. Furthermore, the thermal conductivity of the foam has also been predicted using previous analytical models. The differences with previous values show that it is important to account for the real geometry of the foam to get an accurate value of the thermal conductivity. [ABSTRACT FROM AUTHOR]

Abstract: 3‐D modeling of Mount Etna, the largest and most active volcano in Europe, has for the first time enabled acquiring new information on the volumes of products emitted during the volcanic phases that have formed Mount Etna and particularly during the last 60 ka, an issue previously not fully addressed. Volumes emitted over time allow determining the trend of eruption rates during the volcano's lifetime, also highlighting a drastic increase of emitted products in the last 15 ka. The comparison of Mount Etna's eruption rates with those of other volcanic systems in different geodynamic frameworks worldwide revealed that since 60 ka ago, eruption rates have reached a value near to that of oceanic‐arc volcanic systems, although Mount Etna is considered a continental rift strato‐volcano. This finding agrees well with previous studies on a possible transition of Mount Etna's magmatic source from plume‐related to island‐arc related. As suggested by tomographic studies, trench‐parallel breakoff of the Ionian slab has occurred north of Mount Etna. Slab gateway formation right between the Aeolian magmatic province and the Mount Etna area probably induced a previously softened and fluid‐enriched suprasubduction mantle wedge to flow toward the volcano with consequent magmatic source mixing. [ABSTRACT FROM AUTHOR]

Numerical finite element analysis is considered a reliable tool for response assessment of structures under extreme loadings. When developing finite element models, various geometrical and behavioral assumptions are typically made to simplify the modeling approach and to save on computational cost. The effect of these assumptions on analysis results, however, could be substantial and might significantly alter the decisions pertaining to design, assessment, or retrofit of the structure considered. The importance of accurate modeling, particularly of critical infrastructures, can be vital for post-disaster recovery management following an extreme event. In this study, the seismic response of a six-story hospital building with buckling-restrained braces, located in Memphis, Tennessee, is evaluated for different modeling resolution levels. Different pushover and non-linear time-history analyses are conducted to understand, compare, and evaluate the seismic performance of the structure using both 2-D and 3-D numerical models with and without soil. Various nonlinear features are considered in the simulations including realistic hysteretic behavior of the connections, buckling-restrained braces, and soil-foundation-structure interaction. The results highlight the importance of including representative member and connection models as well as realistic boundary conditions, while employing 3-D simulations, for accurate predictions of system response. [ABSTRACT FROM AUTHOR]

Three-dimensional (3-D) models of archaeological artifacts can be obtained using free or low-cost image-based modeling (IBM) systems. IBM systems generate a 3-D model by processing a set of overlapping digital photographs of an object or scene. Sundials are generally located in inaccessible places, and photography may be the only method to study them. The purpose of this paper is to explore the potential of the 3-D modeling of archaeological objects obtained by IBM systems and embedded in a 3-D interactive portable document format (PDF) file. The process is illustrated by two case studies: a Roman sundial and a historical vertical sundial. The 3-D interactive PDF file allows for measuring some elements in the 3-D model. These measurements can be obtained easily and provide metric information about the sundials without touching them. [ABSTRACT FROM AUTHOR]