Three-dimensional Configuration Research Articles

A BIM-Based Approach for Pavement Monitoring Integrating Data from Non-Destructive Testing Methods (NDTs)

Monitoring of critical civil engineering infrastructures has become a priority for public owners and administrative authorities. Several laws and regulations have been issued on this topic, emphasizing the crucial role of Building Information Modeling (BIM)- based procedures for the design and management of civil infrastructures. This study aims at examining the potential of an interoperable and upgradeable BIM model supplemented by ground-based non-destructive survey data, such as Mobile Laser Scanner (MLS) and Ground-Penetrating Radar (GPR), for the analysis of the potential distresses identified in a transport infrastructure’s pavement. The main goal of the work is to implement an infrastructure management process that aims to reduce the limits associated with the separate observation of these assessments and to provide a more efficient way to store data regarding the status of a linear transport infrastructure, to the advantage of an integrated analysis. As on-site surveys are carried out, preliminary analyses on the condition of the inspected infrastructure are performed by relying on the information provided by Non-Destructive Testing (NDTs) inspections. Subsequently, a digital informative model capable of storing the data obtained by the surveys is generated, integrating both the MLS and GPR information to accurately represent the status of the infrastructure’s pavement in a three-dimensional environment. Data obtained from these instruments were used as the input for the digitalization process, making use of parametric digital elements capable of adapting their configuration to the information provided by the NDT surveys. As more analysis on the surveys’ results is carried out, potential distresses in the deep layers of the pavement are identified, and the information related to these elements is then integrated into the BIM model previously created. The process hereby described allows for an analysis of the three-dimensional configuration of the pavement, along with potential distresses and their location into the road’s superstructure. This digitalization process has shown promising viability for data management aimed at supporting asset managers in various management phases.

Adjoint high-dimensional aircraft shape optimization using a CAD-ROM parameterization

A gradient-based aeroelastic shape optimization framework making use of a reduced order model to substitute a parameterization based on computer-aided design software is presented. This parameterization concept is not novel in principle, but it is embedded here in a complex high-fidelity optimization process and proven for a high-dimensional design space. The design software is used initially to generate a parametric model of a three-dimensional transport aircraft configuration. To streamline the actual optimization process, the computer-aided design model is replaced with a parametric reduced order model based on proper orthogonal decomposition that is capable of predicting discrete surface displacement fields as a function of the design parameters. During the optimization, surface displacements are computed according to the current design parameters and applied on the baseline shape. In every optimization step, the aircraft's steady-state equilibrium of forces and moments are satisfied by a trimming algorithm and the Reynolds-averaged Navier–Stokes solver TAU is coupled with a linear structural finite-element method model. Gradients are computed analytically using geometric sensitivities provided by the reduced order model and by applying the adjoint method to the flow solver and the mesh deformation tool. The workflow is embedded within FlowSimulator, a multiphysics environment for high performance computing. The optimization process is demonstrated for a high-dimensional wing parameterization with 126 degrees of freedom. The aircraft cruise drag could be significantly reduced by 6% on a series of three continuously refined meshes for the aerodynamic analysis. For an accurate representation of the optimal shape by the computer-aided design software after the optimization, the approximation error introduced by the reduced order modelling approach must be sufficiently small. Therefore, the accuracy of the predictions was analyzed. The results identify the main source of the geometric error and quantify their effect on the drag reduction gained by the optimization. We dedicate this article to the memory of our colleague and friend Arno Ronzheimer, whose devotion to CAD modeling was unsurpassed.

Effects of Co Addition on Microstructure Evolution and Efficient Hydrogen Evolution of Self-Supported Fe–P@Cu Immiscible Alloy

In this article, the effects of Co addition on microstructure evolution and catalytic efficiency variation of an Fe–P@Cu immiscible alloy were systematically studied. According to the first-principles molecular dynamics simulations, it was found that P in the Fe–P@Cu alloy with Co addition would be preferentially bonded with Fe and/or Co in the first coordination shell, and Cu and (Fe+Co) atoms tended to appear on the opposite side of P atom in the three-dimensional cluster configuration, which would have a significant guiding effect on the subsequent solidification process. Through the microstructure analysis, it was observed that the addition of Co element had an inhibitory action on the liquid phase separation behavior due to the changes of interfacial tension, resulting in the formation of a fine second phase structure. Through the electrochemistry characteristics, it was found that the overpotentials of Fe–P@Cu metallic catalysts containing 8% Co and 16% Co with a current density of 10 mA/cm2 have been improved to be 160 and 155 mV in 0.5 M H2SO4 respectively. This excellent catalytic performance might be mainly attributed to the rapid transport of ions and the remarkable amount increase of electron transfer, resulting in the obvious promotion of the hydrogen evolution reaction of (FexCo1–x)nP@Cu alloys.

Spatially Defined Cell-Secreted Protein Detection Using Granular Hydrogels: μGeLISA.

Intercellular communication through secreted proteins is necessary in essential processes such as embryo and limb development, disease progression, and immune responses. There exist many techniques to study bulk solution protein concentrations, but there is a limited set of tools to study the concentrations of cell-secreted proteins in situ within diverse cell platforms while retaining spatial information. In this study, we have developed a microgel system that is able to quantitatively measure the cell-secreted protein concentration within defined three-dimensional culture configurations with single-cell spatial resolution, called μGeLISA (microgel-linked immunosorbent assay). This system, which is based on the surface modification of polyethylene glycol microgels, was able to detect interleukin 6 (IL-6) concentrations of 2.21-21.86 ng/mL. Microgels were also able to detect cell spheroid-secreted IL-6 and distinguish between low- and high-secreting single cells. The system was also adapted to measure the concentration of cell-secreted matrix metalloproteinase-2 (MMP-2). μGeLISA represents a highly versatile system with a straightforward fabrication process that can be adapted toward the detection of secreted proteins within a diverse range of cell culture configurations.

Direct Observation of Group-V Dopant Substitutional Defects in CdTe Single Crystals.

Point defect chemistry strongly affects the fundamental properties of materials and has a decisive impact on device performance. The Group-V dopant is prominent acceptor species with high hole concentration in CdTe; however, its local atomic structure is still not clear owing to difficulties in definitive measurements and discrepancies between experimental observations and theoretical models. Herein, we report on direct observation of the local structure for the As dopant in CdTe single crystals by the X-ray fluorescence holography (XFH) technique, which is a powerful tool to visualize three-dimensional atomic configurations around a specific element. The XFH result shows the As substituting on both Cd (AsCd) and Te (AsTe) sites. Although AsTe has been well known as a shallow acceptor, AsCd has not attracted much attention and been discussed so far. Our results provide new insights into point defects by expanding the experimental XFH study in combination with theoretical first-principles studies in II-VI semiconductors.

Eye Morphogenesis in Vertebrates.

Proper eye structure is essential for visual function: Multiple essential eye tissues must take shape and assemble into a precise three-dimensional configuration. Accordingly, alterations to eye structure can lead to pathological conditions of visual impairment. Changes in eye shape can also be adaptive over evolutionary time. Eye structure is first established during development with the formation of the optic cup, which contains the neural retina, retinal pigment epithelium, and lens. This crucial yet deceptively simple hemispherical structure lays the foundation for all later elaborations of the eye. Building on descriptions of the embryonic eye that started with hand drawings and micrographs, the field is beginning to identify mechanisms driving dynamic changes in three-dimensional cell and tissue shape. A combination of molecular genetics, imaging, and pharmacological approaches is defining connections among transcription factors, signaling pathways, and the intracellular machinery governing the emergence of this crucial structure.

Circuit Topology Approach for the Comparative Analysis of Intrinsically Disordered Proteins.

Intrinsically disordered proteins (IDPs) lack a stable native conformation, making it challenging to characterize their structure and dynamics. Key topological motifs with fundamental biological relevance are often hidden in the conformational noise, eluding detection. Here, we develop a circuit topology toolbox to extract conformational patterns, critical contacts, and timescales from simulated dynamics of intrinsically disordered proteins. We follow the dynamics of IDPs by providing a smart low-dimensionality representation of their three-dimensional (3D) configuration in the topology space. Such an approach allows us to quantify topological similarity in dynamic systems, therefore providing a pipeline for structural comparison of IDPs.

Hierarchical Porous Pt/ZrO2 Nanoframework for Efficient Oxygen Reduction Reaction

Rational regulation of the three-dimensional (3D) intrinsic configuration of nanocatalysts is essential for the complex three-phase interfacial mass transfer process in the oxygen reduction reaction (ORR) and proton membrane exchange membrane fuel cells (PEMFCs). In this work, we developed a highly efficient 3D hierarchical porous ORR catalytic system by introducing stable and multiaperture zirconia (ZrO2) and conductive N-doped carbon (NC) into a Pt-based catalyst. We found that the constructed Pt–ZrO2 interface greatly promotes the activation of O2 by modulating the electronic state of Pt nanoparticles. The hierarchical porous structure of a NC-encapsulated nanoframework compensates for the system conductivity, promoting the mass diffusion and the electron transfer of catalytic species, thereby enhancing the ORR activity and stability. This developed hierarchical porous ORR catalytic system exhibits a good mass activity/specific activity of 1.26 A mgPt–1/1.44 mA cm–2, which is 4.5/5.8 times higher than that of commercial Pt/C. Moreover, it exhibits negligible activity decay and morphological stability after 30 K potential cycling. Our findings of integrating hierarchical porous systems to simultaneously optimize the geometric and electric structure of Pt-based catalysts should finally boost their development in practical PEMFCs.

Deciphering three-dimensional bioanode configuration for augmenting power generation and nitrogen removal in air–cathode microbial fuel cells

In this study, the engineering-oriented three-dimensional (3D) bioanode concept was applied, demonstrating that spiral-stairs-like/rolled carbon felt (SCF/RCF) configurations achieved good performances in air–cathode microbial fuel cells (ACMFCs). With the 3D anodes, ACMFCs generated significantly higher power densities of 1535 mW/m3 (SCF) and 1800 mW/m3 (RCF), compared with that of a traditional flat carbon felt anode (FCF, 315 mW/m3). The coulombic efficiency of 15.39 % at SCF anode and 14.34 % at RCF anode also is higher than the 7.93 % at FCF anode. The 3D anode ACMFCs exhibited favorable removal of chemical oxygen demand (96 % of SCF and RCF) and total nitrogen (97 % of SCF, 99 % of RCF). Further results show that three-dimensional anode structures could enrich more electrode surface biomass and diversify the biofilm microbial communities for promoting bioelectroactivity, denitrification, and nitrification. These results demonstrate that three-dimensional anodes with active biofilm is a promising strategy for creating scalable MFCs-based wastewater treatment system.

Controllable synthesis of porous 3D Pd loaded ZIF-67/g-C3N4 hierarchical nanostructure for efficient detection of NO2 gas at room temperature

The two-dimensional (2D) g-C3N4 nanosheets have been widely recognized for their great potential in gas sensing. However, the disadvantages brought by layer stacking of two-dimensional nanosheets also seriously affect their performance and application. In this paper, three-dimensional hydrangea-like Pd-ZIF-67/g-C3N4 was prepared for the detection of nitrogen dioxide gas at room temperature via a simple hydrothermal method. The Pd-ZIF-67/g-C3N4 gas sensor exhibited excellent sensing properties with highest sensing response (23.8–100 ppm), ultrafast response speed (0.5 s) and lowest limit of detection (10 ppb) at room temperature. Moreover, it also manifests excellent reversibility and durability, optimal stability and commendable selectivity towards NO2 gas. This excellent performance is due to the three-dimensional spatial configuration, synergistic effect and catalytic action of Pd. In general, the constructed structure and the proposed design strategy have a certain promoting role in promoting the creation of high performance gas sensors with three-dimensional heterogeneous structures based on two-dimensional nanosheets.

Fe-doping-induced cation substitution and anion vacancies promoting Co3O4 hexagonal nanosheets for efficient overall water splitting

Water electrolysis is a green technology for hydrogen fuel production, but greatly hampered by the slow kinetics of the anodic oxygen evolution reaction (OER) and the cathodic hydrogen evolution reaction (HER). In this work, we report an efficient strategy to simultaneously promote OER and HER performance on Co3O4 hexagonal nanosheets via Fe-doping-induced cation substitution and anion vacancies. Benefiting from the integrated advantages of well-defined ultrathin nanosheets, abundant vacancies, and unique three-dimensional electrode configuration, the optimized Fe-doped Co3O4 hexagonal nanosheets/nickel foam (Fe0.4Co2.6O4 HNSs/NF) can achieve overpotentials of 328 mV at 100 mA cm−2 for OER and 315 mV at 500 mA cm−2 for HER, respectively, which is comparable to those of the benchmark noble electrocatalysts. More importantly, the Fe0.4Co2.6O4 HNSs/NF-assembled electrolyzer for overall water splitting can deliver a current density of 100 mA cm−2 at a cell voltage as low as 1.66 V and work steadily at 50 mA cm−2 with a negligible fading up to 140 h.

Straightness Perception Mechanism of Scraper Conveyor Based on the Three-Dimensional Curvature Sensing of FBG

In order to solve the key technical problem of accurate perception of the straightness of a scraper conveyor in intelligent mining of coal mines, a three-dimensional (3D) curvature sensor of fiber Bragg grating (FBG) is designed and developed based on the curvature sensing principle of FBG. The grating string embedded in the FBG curvature sensor is simulated under the radius of curvature of 100 m, 200 m, 300 m, 400 m and 500 m. The results show that the strain of the built-in FBG string is linearly related to the curvature at the bend of the FBG string. The simulation results are consistent with the theoretical results, which verifies the rationality of the sensor design. Based on the discrete curvature information obtained by the 3D curvature sensor of FBG, the curve reconstruction algorithm is derived by using the method of fitting recursion, and the bending shape fitting perception and curve reconstruction of the scraper conveyor is realized. A test platform for the three-dimensional bending of the scraper conveyor is set up. The measuring effect of perceived and actual shape at the straight and bending states of the scraper conveyor is verified. The test results show that the measured curve is basically the same as the perceptual curve in the three-dimensional bending configuration of the scraper conveyor, and the error of the direction of each coordinate axis is not more than ±15 mm, which can meet the requirements of the accuracy of detecting the straightness of the intelligent work.

A kinetic origami surfaces methodology

This paper presents original research developed during PhD research. It proposes a multidisciplinary process as a methodology for the construction of thick, rigid origami surfaces to be used for kinetic architectural purposes. Origami surfaces that fold rigidly allow for strict geometry-based simulations that can reproduce rigorous rigid kinematics from the unfolded to the completely folded state, which is particularly important in large scale structures where motion must be predictable. The considered surfaces are regularly tessellated and have planar initial and final states. Through movement, these can assume a cycle of folding states with different three-dimensional configurations. The proposed method departs from concept, moves to geometry definition, kinematic simulation, structural evaluation, construction, and implementation for folding surfaces. It includes steps for evaluation and correction of issues as well as strategies for construction through digital fabrication with planar, thick materials. Its validity is demonstrated by its application in a constructed case study.

Three-dimensional coupling of electron cyclotron drift instability and ion–ion two stream instability

Electron cyclotron drift instability (ECDI) and ion–ion two stream instability (IITSI) are both kinetic instabilities that can be present in low-temperature, partially magnetized plasmas. The coupling of instabilities in a three-dimensional configuration leads to the existence of more than one unstable roots to the kinetic dispersion relation. In this paper, a generalized method has been developed for numerically evaluating solutions to the three-dimensional dispersion relation for coupled ECDI and IITSI, assuming cold singly and doubly charged ions and a Maxwellian velocity distribution function for the electrons. The present study demonstrates the coupling between ECDI and IITSI that affects the most unstable mode as a function of the wavenumbers in three dimensions and various plasma properties, including the applied electric field, magnetic field, electron temperature, ion velocities, and plasma density. One of the most notable results is that, while the most unstable mode with the largest growth rate is in the direction of the E×B drift in the two-dimensional cases, the most unstable mode for the three-dimensional configuration occurs in the oblique direction between the applied electric field and the E×B drift. This agrees with experimental observations in cross field plasma sources using coherent Thomson scattering.

Dimensions of bony Kambin's triangle pertaining to endoscopic procedure

BackgroundEndoscopic procedures nowadays are successful, minimally invasive, and safer, with fewer intraoperative and postoperative complications and shorter hospital stays. Kambin's triangle (KT) is the three-dimensional configuration that is used as a transforaminal anatomical corridor for epidural steroid injections and endoscopic surgeries for various lumbar pathologies. This study aims to estimate the dimensions of KT and diameter of the cannula for the transforaminal surgical approaches using KT in the Chhattisgarh population. MethodsSeven human cadavers (three males and four females) were included in the study for observing KT. Dissection was done to carefully clear landmarks, including the vertebral bodies, intervertebral disc, exiting nerve root, and superior articular process. Base (a horizontal plane passing through the superior border of the caudal vertebra) and height (along the superior articular process of the inferior vertebra in line with the articular facet) were measured. Hypotenuse, semiperimeter of the triangle, area of triangle, diameter, and area of the inscribed circle were calculated. ResultsHeight, base, and inscribed circle diameter increased from L1-L2 to L4-L5 then decreased to L5-S1. There was no statistically significant difference between males and females. The safest admissible cannula diameter according to the current study that can be used at all levels in KT was 6.06 mm. ConclusionThis study provides the safest cannula size to be considered in the patients of the Chhattisgarh population during transforaminal approaches in the lumbar area. Minimally invasive surgery and shorter hospitalization are vital criteria to evaluate any surgery these days.

Influence of upstream wall slope on aerodynamic properties of a rectangular cavity in rarefied hypersonic flows

A comprehensive numerical study is performed to reveal influence of the upstream wall slope on aerodynamic properties as rarefied hypersonic flows pass through the two- and three-dimensional cavity configurations using the direct simulation Monte Carlo (DSMC) method. In this work, slope effect is obtained by the cavity upstream wall sloping upward and downward as well as bulging partially. Besides, cases of freestream with different velocities and altitudes are taken into account to examine the slope effect. It is found that cavity flow is transformed from the open type to the transitional and finally to the closed as the cavity upstream wall gradually slopes upward, promoting the heat energy exchange between gas molecules with the cavity floor, and meanwhile achieving a considerable rate of decrease of the peak heat flux on the reattachment corner. However, the upstream wall sloping downward or bulging partially seems to only have a slight effect on cavity flow and wall heat flux. It's worth noting that slope effect is closely related to velocity and altitude of the freestream, such as the greater the velocity and altitude, the stronger the slope effect. For the three-dimensional cavity configuration, influence of the upstream wall slope on cavity flow and wall heat flux is weaken considerably due to the three-dimensional effect. From the perspective of optimal design for the hypersonic thermal protection system, the cavity with an upward upstream wall is proposed because it not only reduces peak heat flux on the reattachment corner, but also decreases gas temperature inside the cavity.

Does multi-way, long-range chromatin contact data advance 3D genome reconstruction?

BackgroundMethods for inferring the three-dimensional (3D) configuration of chromatin from conformation capture assays that provide strictly pairwise interactions, notably Hi-C, utilize the attendant contact matrix as input. More recent assays, in particular split-pool recognition of interactions by tag extension (SPRITE), capture multi-way interactions instead of solely pairwise contacts. These assays yield contacts that straddle appreciably greater genomic distances than Hi-C, in addition to instances of exceptionally high-order chromatin interaction. Such attributes are anticipated to be consequential with respect to 3D genome reconstruction, a task yet to be undertaken with multi-way contact data. However, performing such 3D reconstruction using distance-based reconstruction techniques requires framing multi-way contacts as (pairwise) distances. Comparing approaches for so doing, and assessing the resultant impact of long-range and multi-way contacts, are the objectives of this study.ResultsWe obtained 3D reconstructions via multi-dimensional scaling under a variety of weighting schemes for mapping SPRITE multi-way contacts to pairwise distances. Resultant configurations were compared following Procrustes alignment and relationships were assessed between associated Procrustes root mean square errors and key features such as the extent of multi-way and/or long-range contacts. We found that these features had surprisingly limited influence on 3D reconstruction, a finding we attribute to their influence being diminished by the preponderance of pairwise contacts.ConclusionDistance-based 3D genome reconstruction using SPRITE multi-way contact data is not appreciably affected by the weighting scheme used to convert multi-way interactions to pairwise distances.

3D calculation studies of dislocation density in a β-Ga2O3 crystal grown by vertical Bridgman method

This paper reports numerical study of dislocation-density distribution in a β-gallium oxide. We calculated time dependent distributions of temperature and velocity in a furnace of a vertical Bridgman method. Then, we used Alexander-Haasen (AH) model in three-dimensional configuration. Growth directions were set to show different orientations: [010] and [001]. The results obtained from [010] grown crystal show that large number of dislocation distributed at the periphery of the [010] grown crystals at an initial stage of the crystal growth process while the maximum dislocation density lies along [100] at the middle stage of the process. The results obtained from [001] grown crystal show that large number of dislocation distributed also lies along [100] at the middle stage of the process.

Performance Testing of Person Passable Openings to Evaluate Accepted Risk

Researchers at Sandia National Laboratories, in conjunction with the Nuclear Energy Institute and Light Water Reactor Sustainability Programs, have conducted testing and analysis to reevaluate and redefine the minimum passible opening size through which a person can effectively pass and navigate. Physical testing with a representative population has been performed on both simple two-dimensional (rectangular and circular cross sections up to 91.4 cm in depth) and more complex three-dimensional (circular cross sections of longer lengths up to 9.1 m and changes in direction) opening configurations. The primary impact of this effort is to define the physical design in which an adversary could successfully pass through a potentially complex opening, as well as to define the designs in which an adversary would not be expected to successfully traverse a complex opening. These data can then be used to support risk-informed decision making.

Bonding states of hydrogen for supported Ti clusters on pristine and defective graphene

To determine whether graphene-supported Ti clusters can synergistically store hydrogen through Kubas and spillover effect, we systematically investigate the growth pattern of Tin (n = 1–10) clusters on pristine and defective graphene and analyze multiple types of bonding states of hydrogen in detail. For pristine graphene, the most stable Tin (n = 1–10) clusters are the quasi-planar structure except for supported Ti4 and Ti5. The Ti dissociation energies and the binding energy of Tin clusters gradually increase with increasing n, which indicates that larger Tin clusters tend to form. Efficient spillover will occur on single-site Ti Catalysts at low hydrogen concentration due to the lower hydrogen spillover energy barrier (3.05 eV), while the energy barrier of hydrogen migration from Tin (n = 2–7) clusters to graphene on the cluster is 5.34–6.82 eV. The Ti: H ratio is a maximum of 1:8 for the single-site Ti catalyst, while decreases with the Tin cluster increases. Therefore, the pristine graphene-supported Ti nanoclusters are more suitable as substrates for hydrogen adsorbent rather than spillover. The introduced defects make Tin clusters have three-dimensional conical configurations from n = 4. Ti3 and Ti6 are the most stable clusters. Moreover, the migration energy barriers of H atoms on them decrease from 6.54 eV to 6.82 eV–4.32 eV and 3.42 eV, respectively. Our results explain recent experimental phenomena [Appl Phys Lett 2015; 106: 083,901. ACS Energy Lett 2022; 7 (7): 2297–2303] in depth at the molecular level.