Integrated 3D Model Research Articles

3D numerical simulation on thermal hydraulic characteristics in integrated sodium pool of PHENIX reactor during dissymmetric test

Temperature distribution of internals under different transient events is important for the design and safety analysis of pool-type sodium-cooled fast reactor (SFR). It is influenced by overall flow and thermal stratification phenomena in the multi-scale sodium pool. Due to the difficulty to perform experiment, three-dimensional (3D) numerical method is usually adopted for obtaining the temperature distribution and analyzing complex phenomena in pool-type SFRs. It needs to be further validated using the published benchmark, such as PHENIX Dissymmetric Test. The simplified model in system code and 3D model of local area in current study cannot capture the complex coupling effect of cold and hot pool during dissymmetric test. In this paper, an integrated 3D model of PHENIX reactor primary system both including cold and hot pools is established. The steady and transient simulation with 1800 s of PHENIX Dissymmetric Test process are carried out. The key parameters of simulation are compared with the available experimental and predicted data, which achieves good agreement. Overall flow and asymmetric temperature distribution phenomena in cold pool, hot pool and local area of IHX inlet are simulated. There is a temperature difference between different sides of IHX inlet during a period after scram, with the maximum value of 80 ℃ approximately at 90 s. This validated numerical method can be further used for the analysis of thermal hydraulic characteristics in other pool-type SFR. The obtained temperature distribution of internals can provide the reference for the stress assess of structures in the engineering design.

Retraction Note: An integrated 3D model based face recognition method using synthesized facial expressions and poses for single image applications

Retraction Note: An integrated 3D model based face recognition method using synthesized facial expressions and poses for single image applications

Research on 3D Visualization of Real Scene in Subway Engineering Based on 3D Model

As an urban infrastructure project, subway engineering exhibits the characteristics of large scale, trans-regional presence, and complex environmental conditions. The three-dimensional (3D) real scene of subway engineering aims to visually present the project features by creating a virtual environment in the 3D form by integrating numerous geographical scenes and entities. However, existing methods of geometric data integration and model visualization are insufficient for handling the diverse and heterogeneous data types encountered in this process. To address these challenges, this study proposes a framework for real-scene 3D visualization management in subway engineering, establishing a technical process of multi-source data integration for organizing 3D models within the scene, and developing a visualization display strategy that incorporates octree and level of detail principles for multi-scale hierarchical dynamic loading of 3D Scene. To validate the proposed method, a prototype system is developed with Geographic Information System (GIS) and Building Information Modeling (BIM) technology and applied to an actual subway project. The results demonstrate that this method ensures effective integration and management of data, enabling the display of real scenes in an integrated 3D model in a web environment.

Correction to: An integrated 3D model based face recognition method using synthesized facial expressions and poses for single image applications

Correction to: An integrated 3D model based face recognition method using synthesized facial expressions and poses for single image applications

ACCURACY ASSESSMENT TOWARD MERGING OF TERRESTRIAL LASER SCANNER POINT DATA AND UNMANNED AERIAL SYSTEM POINT DATA

Terrestrial Laser Scanning (TLS) techniques are widely preferred for 3D models of small and large objects, buildings, and historical and cultural heritages. However, sometimes relying on a single method for 3D modelling an object/structure is insufficient to arrive at a solution or meet expectations. For example, Unmanned Aerial Systems (UAS) provide perspective for building roofs, while terrestrial laser scanners provide general information about building facades. In this research, several facades of a selected building could not be modelled using terrestrial laser scanning, and UAS was used to complete the missing data for 3D modelling. The transformation matrix, a linear function, is created to merge different data types. In the transformation matrix, the scale was found to be 1:1.012. The accuracy analysis of the produced 3D model was also made by comparing the spatial measurements taken from different building facades and the differences in the measurement values obtained from the 3D model and calculating statistically. According to the accuracy analysis results, the Root Mean Square Error (RMSE) value is approximately 3 cm. The results of the accuracy research, which are within the 95% confidence interval with the three-sigma rule, are approximately 2 cm as RMSE. As a result of the study, it was determined that the data obtained from UAV photogrammetry and the data obtained by the TLS technique could be combined, and the integrated 3D model obtained can be used more efficiently.

3D Modeling of Bosscha Observatory With TLS and UAV Integration Data

Terrestrial Laser Scanner is a tool capable of generating millions 3D points with mm accuracy, but upper structure is difficult to model. Unmanned Aerial Vehicle is an unmanned aircraft system technology that can provide structural data on buildings. Measurements with one technique can lead to unsatisfactory results, so an integration process is carried out to obtain a more accurate 3D model. The purpose of this research is to see the successful integration of TLS and UAV point cloud data for 3D modeling. The data used is secondary data from previous research. TLS and UAV data were processed with Agisoft Metashape and Cyclone in the same coordinate system. The integration process is carried out by aligning the same point cloud between the two data in CloudCompare with an RMSE of 25.60 mm. Validation is done by comparing the distance between the results of the 3D model with the actual conditions. The integrated 3D model can be implemented for the purposes of Bosscha Observatory 3D modeling.

A practical workflow for the 3D reconstruction of complex historic sites and their decorative interiors: Florence As It Was and the church of Orsanmichele

The Digital Humanities project Florence As It Was (http://florenceasitwas.wlu.edu) seeks to reconstruct the architectural and decorative appearance of late Medieval and early Modern buildings by combining 3D point cloud models of buildings (i.e. extant structures such as chapels, churches, etc.) with 3D rendered models of artworks that were installed inside them during the fourteenth and fifteenth centuries. This paper documents a novel bifurcated workflow that allows the construction of such integrated 3D models as well as an example case study of a church in Florence, Italy called Orsanmichele (https://3d.wlu.edu/v21/pages/orsanmichele2.html). The key steps worked out in the optimized workflow include: (1) art historical research to identify the original artworks in each building, (2) the use of LiDAR scanners to obtain 3D data (along with associated color information) of the interiors and exteriors of buildings, (3) the use of high resolution photogrammetry of works of art (i.e. paintings and sculptures) which have been removed from those buildings and are now in public collections, (4) the generation of point clouds from the 3D data of the buildings and works of art, (5) the editing and cojoining of a textured polygon model of artworks with a reduced size (using novel algorithms) point cloud model of the buildings in an open-source software tool called Potree so that artworks can be embedded in their original architectural settings, and (6) the annotation of these models with scholarly art historical texts that present viewers immediate access to information, archival evidence, and historical descriptions of these spaces. The integrated point cloud and textured models of buildings and artworks, respectively, plus annotations are then published with Potree. This process has resulted in the development of highly accurate virtual reconstructions of key monuments from the Florentine Middle Ages and Renaissance (like the fourteenth century building of Orsanmichele and the multiple paintings that were once inside it) as they originally appeared. The goal of this project is to create virtual models for scholars and students to explore research questions while providing key information that may assist in generating new projects. Such models represent a significant tool to allow improved teaching of art and architectural history. Furthermore, since the assigned location of some of the historic artworks within these sites are not always firmly known, the virtual model allows users to experiment with potential arrangements of objects in and on the buildings they may have originally decorated.

The contribution of integrated 3D model analysis to Protoaurignacian stone tool design.

Protoaurignacian foragers relied heavily on the production and use of bladelets. Techno-typological studies of these implements have provided insights into crucial aspects of cultural variability. However, new technologies have seldom been used to quantify patterns of stone tool design. Taking advantage of a new scanning protocol and open-source software, we conduct the first 3D analysis of a Protoaurignacian assemblage, focusing on the selection and modification of blades and bladelets. We study a large dataset of complete blanks and retouched tools from the early Protoaurignacian assemblage at Fumane Cave in northeastern Italy. Our main goal is to validate and refine previous techno-typological considerations employing a 3D geometric morphometrics approach complemented by 2D analysis of cross-section outlines and computation of retouch angle. The encouraging results show the merits of the proposed integrated approach and confirm that bladelets were the main focus of stone knapping at the site. Among modified bladelets, various retouching techniques were applied to achieve specific shape objectives. We suggest that the variability observed among retouched bladelets relates to the design of multi-part artifacts that need to be further explored via renewed experimental and functional studies.

RETRACTED ARTICLE: An integrated 3D model based face recognition method using synthesized facial expressions and poses for single image applications

RETRACTED ARTICLE: An integrated 3D model based face recognition method using synthesized facial expressions and poses for single image applications

An integrated 3D method to assess the application potential of GWHP systems in fluvial deposit areas

Fluvial deposits are commonly abundant in groundwater resources, indicating very high potential for the application of groundwater heat pump (GWHP) systems. To better understand the geospatial variation in geothermal potential, this paper presents a multidisciplinary 3D approach to assess aquifer-based geothermal resources in the Han River area in Hubei Province, China. The geological setting was determined by collecting data from 1286 drilling holes. The thermophysical-hydraulic properties were investigated, and the geospatial variation was characterized by 3D geological modeling. A GIS-based procedure was deployed for the assessment of the geothermal potential by extracting parameters from these 3D models as input. The results show that the middle reaches have the highest potential due to the great thickness of the aquifer layers, followed by the upper reaches, and the lower reaches have the lowest potential. The validation of 3 specific cases, located in the upper, middle, and lower reaches, shows that the model has uncertainties of 6.1%, 14.7% and 5.5%, respectively. This implies that the accuracy of the estimated potential depends on both the available drilling data and geological heterogeneity. This study shows that integrated 3D modeling and the GIS-based approach could be useful in geothermal planning in fluvial deposit areas.

Qlone®: A Simple Method to Create 360-Degree Photogrammetry-Based 3-Dimensional Model of Cadaveric Specimens.

Human cadavers are an essential component of anatomy education. However, access to cadaveric specimens and laboratory facilities is limited in most parts of the world. Hence, new innovative approaches and accessible technologies are much needed to enhance anatomy training. To provide a practical method for 3-dimensional (3D) visualization of cadaveric specimens to maximize the utility of these precious educational materials. Embalmed cadaveric specimens (cerebrum, brain stem, and cerebellum) were used. The 3D models of cadaveric specimens were built by merging multiple 2-dimensional photographs. Pictures were taken with standard mobile devices (smartphone and tablet). A photogrammetry program (Qlone®, 2017-2020, EyeCue Vision Technologies Ltd, Yokneam, Israel), an all-in-one 3D scanning and augmented reality technology, was then used to convert the images into an integrated 3D model. High-resolution 360-degree 3D models of the cadaveric specimens were obtained. These models could be rotated and moved freely on different planes, and viewed from different angles with varying magnifications. Advanced editing options and the possibility for export to virtual- or augmented-reality simulation allowed for better visualization. This inexpensive, simple, and accessible method for creating 360-degree 3D cadaveric models can enhance training in neuroanatomy and allow for a highly realistic surgical simulation environment for neurosurgeons worldwide.

Seabed liquefaction around breakwater heads at a river mouth: An integrated 3D model

In this paper, a 3D model is developed to investigate the foundation stability around breakwaters at a river mouth, where both ocean waves and river currents are considered. The present model consists of flow and seabed sub-models. In the flow sub-model, the VARANS equations is used to describe hydrodynamic process, while the dynamic u−p approximation is employed in the seabed sub-model. Based on the integrated model, both oscillatory and residual liquefaction phenomenon is investigated by adopting the poro-elastic and poro-elastoplastic seabed models, respectively. The numerical results reveal that the breakwaters at the river mouth with the river current significantly alter the hydrodynamic properties around breakwater heads. Furthermore, the dynamic soil responses and liquefaction zones predicted by the poro-elastic and poro-elastoplastic seabed models show the completely different development trend, which the latter seabed has more intense and severe reactions. The parametric study indicates that the breakwater foundation is more likely to be liquefied in a loosely deposited soil under larger waves. The river currents can exacerbate the liquefaction condition in the region near breakwater heads. In addition, the pore pressure is smaller in front of a milder slope of breakwater flank and a round breakwater head with a smooth slope.

Knowledge-based 3D reconstruction of bridge structures using UAV-based photogrammetric point cloud

Due to the rapid developments of smart cities, 3D modeling of urban infrastructures has become essential for making decisions in urban management and planning applications. 3D modeling of the bridge structure, as one of the most important civil structures in transportations, includes many challenges due to geometrical and structural complexities. A knowledge-based approach based on a 2D projection method is proposed for automatic 3D reconstruction of the main bridge elements including the railing, body, piers, and abutment using dense point clouds of unmanned aerial vehicle images. The knowledge is the geometric relations between the bridge elements to model different types of bridge structures. In the first step, the input point cloud is segmented into the major elements using a fuzzy c-means clustering algorithm. Next, the 2D model of each element is generated using a 2D projection-based reconstruction technique. Then 3D models of elements are created by extruding 2D models into the 3D space. Finally, an integrated 3D model of the bridge structure is formed by merging individual 3D models in a CAD format. In order to evaluate the performance of the proposed modeling framework, the length differences of the elements are compared with a reference model. In addition, the geometric distances between the final models and the input point cloud are calculated. Accordingly, a median error of about 3 cm between the length of the elements in the reference and reconstructed models and 3.8 cm between the reconstructed models and corresponding point clouds highlight the effectiveness of the proposed method to generate 3D models of different bridges.

A PROJECTION-BASED RECONSTRUCTION ALGORITHM FOR 3D MODELING OF BRIDGE STRUCTURES FROM DRONE-BASED POINT CLOUD

Abstract. This paper presents a projection-based method for 3D bridge modeling using dense point clouds generated from drone-based images. The proposed workflow consists of hierarchical steps including point cloud segmentation, modeling of individual elements, and merging of individual models to generate the final 3D model. First, a fuzzy clustering algorithm including the height values and geometrical-spectral features is employed to segment the input point cloud into the main bridge elements. In the next step, a 2D projection-based reconstruction technique is developed to generate a 2D model for each element. Next, the 3D models are reconstructed by extruding the 2D models orthogonally to the projection plane. Finally, the reconstruction process is completed by merging individual 3D models and forming an integrated 3D model of the bridge structure in a CAD format. The results demonstrate the effectiveness of the proposed method to generate 3D models automatically with a median error of about 0.025 m between the elements’ dimensions in the reference and reconstructed models for two different bridge datasets.

Neural tube patterning: From a minimal model for rostrocaudal patterning toward an integrated 3D model

SummaryRostrocaudal patterning of the neural tube is a defining event in vertebrate brain development. This process is driven by morphogen gradients which specify the fate of neural progenitor cells, leading to the partitioning of the tube. Although this is extensively studied experimentally, an integrated view of the genetic circuitry is lacking. Here, we present a minimal gene regulatory model for rostrocaudal patterning, whose tristable topology was determined in a data-driven way. Using this model, we identified the repression of hindbrain fate as promising strategy for the improvement of current protocols for the generation of dopaminergic neurons. Furthermore, we combined our model with an established minimal model for dorsoventral patterning on a realistic 3D neural tube and found that key features of neural tube patterning could be recapitulated. Doing so, we demonstrate how data and models from different sources can be combined to simulate complex in vivo processes.

Integration of 3D models of structures and geological composition as an underground infrastructure model

To develop three-dimensional (3D) models as examples of the infrastructure model concept which would be useful for the operation and maintenance or design and construction of underground facilities we integrated 3D models of the geological composition, the structure and the lifeline facilities (water supply and sewerage system, city gas line, electrical power and communication lines) for the underground mall named ESCA in Nagoya City, Japan. In addition to the above 3D models, 3D structural models of tunnels of the underground railway passing underneath ESCA are developed based on as-built drawings in cooperation with the transportation authority of Nagoya City, and settlements occurred by that construction are visualized in 3D models from a record of the construction of tunnels of that subway. ESCA built out a 3D data platform with browser software for daily maintenance and planning of modification work of the underground mall.

A highly efficient numerical method to investigate the conductivity of CNT/polymer composite

Compared to conventional electronic composites, polymer nanocomposites containing carbon nanotubes (CNT) have superior electrical properties. In the research, a highly efficient numerical method used to calculate the resistivity of the CNT/polymer composite is presented based on an integrated three-dimensional (3D) statistical resistor network model (RNM) which incorporates the tunneling effect between neighboring nanotubes. By this 3D RNM, the electrical properties of a composite brick in which a certain number of CNT are distributed randomly can be calculated. However, to guarantee the convergence of calculation, the number of CNTs must be larger than a threshold, and this may cause the calculation to be very time-consuming. In order to improve the computational efficiency, a modified calculation scheme using coarse-net model (CNM) is proposed. According to the scheme, a composite brick containing a large number of CNTs is divided into an array of cells, each of which has a limited volume and contains a small number of CNTs. These cells are assumed to be connected in a 3D network whereby each cell is considered as a resistor and its resistance can be calculated by the original integrated 3D model efficiently. Statistically, the effective resistance of such a resistor network that can be evaluated by Kirchhoff’s current law is the same as the resistance of the composite brick. The comparison between the conventional RNM and the CNM proves that the latter can improve the computational efficiency tremendously.

A digital control system designed for ore thermal furnaces producing metallurgical silicon

This paper considers the key control issues related to non-adjustable parameters in the production of metallurgical silicon in ore thermal furnaces. A series of experiments has been conducted to confirm the possibility of introducing the electrode off-position control. Thus, additional control parameters were introduced in the process control system. The electrode positioning algorithm was tested and adjusted to minimize electrode bending and reduce the risk of breakage and to minimize end cracking and spalling during restarting in the current production environment. An integrated 3D model of the thermal field distribution has been developed and built that accounts for the charcoal moisture content, the position of the electrodes and the power emitted as the charge gets hot. Substantiation is given to the application of this adaptive adjustment algorithm to control the changing parameters as determined by the process conditions, such as the moisture content of the charge, the position of the electrode, the power mode of the furnace. The authors propose to expand the existing control system by adding a digital module, i.e. due to the integration of electrode off-position signals and the use of the adaptive adjustment algorithm and avoiding using any additional corrective signals. This research was carried out as part of the Governmental Assignment No. 075-03-2020-127/1 for the year of 2020, Project No. FSRW-2020-0014. Subject: A crossdisciplinary approach to the comprehensive exploitation of natural resources and conservation. Area (a 2020 topic): “Comprehensive processing of minerals and man-made materials and gasification of solid hydrocarbons: A review and concept elaboration”. As greenhouse gases and carbon are produced as a result of electrode destruction, it is proposed to use the method of gasification and dispose of the heat produced.

How well do integrated 3D models predict alveolar defects after treatment with clear aligners?

To evaluate the accuracy of integrated models (IMs) constructed by pretreatment cone-beam computed tomography (pre-CBCT) in diagnosing alveolar defects after treatment with clear aligners. Pre-CBCT and posttreatment cone-beam computed tomography (CBCT) scans from 69 patients who completed nonextraction treatment with clear aligners were collected. The IMs comprised anterior teeth in predicted positions and alveolar bone from pre-CBCT scans. The accuracy of the IMs for identifying dehiscences or fenestrations was evaluated by comparing the means of the defect volumes, absolute mean differences, and Pearson correlation coefficients with those measured from post-CBCT scans. Defect prediction accuracy was assessed by sensitivity, specificity, positive predictive values, and negative predictive values. Factors possibly affecting changes in mandibular alveolar defects were analyzed using a mixed linear model. The IM measurements showed mean deviations of 2.82 ± 9.99 mm3 for fenestrations and 3.67 ± 9.93 mm3 for dehiscences. The absolute mean differences were 4.50 ± 9.35 mm3 for fenestrations and 5.17 ± 9.24 mm3 for dehiscences. The specificities of the IMs were higher than 0.8, whereas the sensitivities were both lower (fenestration = 0.41; dehiscence = 0.53). The positive predictive values were unacceptable (fenestration = 0.52; dehiscence = 0.62), and the overall reliability was low (<0.80). Molar distalization and proclination were positively correlated with significant increases in alveolar defects at the mandibular incisors after treatment. Alveolar defects after clear aligner treatment cannot be simulated accurately by IMs constructed from pre-CBCT. Caution should be taken in the treatment of crowding with proclination and molar distalization for the safety of alveolar bone at the mandibular incisors.

Integrating 3D modeling, sustainability and cost estimating at the conceptual design stage of bridges

Integrated 3D modeling adaptation to infrastructure has been slow due to technical challenges, such as the lack of interoperability between software. To fill this gap, a versatile model with 3D modeling capabilities was developed to assist in designing sustainable bridges at the conceptual design stage. The model incorporates a rule-based expert system and four modules, namely, 3D CAD modeling, bridge sustainability rating system (BrSRS), bridge environmental performance strategy mapping (BrEPSM), and conceptual cost estimation. The 3D CAD module was developed using the Graphics.DrawLine method. The BrSRS and BrEPSM modules were developed by amalgamation of the identified pertinent sustainable and footprint indicators. The model aims to provide bridge type recommendations, allow customization of a sustainable bridge, illustrate forecasted footprint levels, present the conceptual design in AutoCAD’s 3-dimensional (3D) mode, facilitate a recalculation process when the bridge’s dimensions are altered, and generate a conceptual cost estimate.