Three-dimensional Approach Research Articles

A Particle Finite Element Method for Additive Manufacturing Simulations

Abstract In this work, the particle finite element method (PFEM) is extended to simulate additive manufacturing processes in a variety of different complicated geometries. A three-dimensional α-shape approach is used to carry out the material addition procedure. It overcomes the limitation of merely employing the traditional element birth and death technique and reduces the degrees-of-freedom compared to this technique. Furthermore, numerical examples are used to evaluate and demonstrate the applicability of the PFEM method for additive manufacturing within the framework of a weakly coupled thermoelasticity formulation. During additive manufacturing operations, deflections, stresses, and temperature are computed using a user-defined implementation in FEniCS.

Pediatric orbital fractures.

The aim of this study was to summarize current evidence on the clinical presentation, evaluation, and management of pediatric orbital fractures. Recent trends in management strategies as well as emerging surgical techniques for pediatric orbital fracture repair are presented. Although somewhat limited, growing bodies of evidence support a conservative approach with close follow up in pediatric orbital fractures. For those patients necessitating surgical repair, resorbable implants are increasingly preferred given their lack of donor site morbidity and a minimal impact on the developing craniofacial skeleton. There are emerging data reporting the use of three-dimensional (3D) printing-assisted approaches and intraoperative navigation; however, more research is needed to assess their applicability in the pediatric population. There are few studies with large patient cohorts and long-term follow up given the rare incidence of pediatric orbital fractures, which restricts the generalizability of research on the topic. The studies available increasingly suggest that fractures without clinical evidence of entrapment can be managed conservatively with close follow up. A variety of reconstructive implants are available for those fractures necessitating repair. Donor site morbidity, availability, and need for additional procedures should all be factored into the reconstructive decision-making process.

Simulating the spatial impacts of a coastal barrier in Galveston Island, Texas: a three-dimensional urban modeling approach

Due to its vulnerability to hurricanes, Galveston Island, TX, USA, is exploring the implementation of a coastal surge barrier (also referred to as the ‘Ike Dike’) for protection from severe flood events. This research evaluates the predicted effects that the coastal spine will have across four different storm scenarios, including a Hurricane Ike scenario and 10-year, 100-year, and 500-year storm events with and without a 2.4 ft. sea level rise (SLR). To achieve this, we develop a 1:1 ratio, 3-dimensional urban model and ran real-time flood projections using ADCIRC model data with and without the coastal barrier in place. Findings show that inundated area and property damages due to flooding will both significantly decrease if the coastal spine is implemented, with a 36% decrease in the inundated area and $4 billion less in property damage across all storm scenarios, on average. When including SLR, the amount of protection of the Ike Dike diminishes due to flooding from the bay side of the island. While the Ike Dike does appear to offer substantial protection from flooding in the short term, integrating the coastal barrier with other non-structural mechanisms would facilitate more long-term protection when considering SLR.

Automatic Generation Construction Shop Design Model of the MEP Hanger Based on BIM

Due to the growing complexity of mechanical, electrical and plumbing (MEP) functions, the design, production and installation of hanger based on MEP has become low efficiency in traditional ways. Compared with the Computer-Aided Design (CAD) approach, the MEP hanger three-dimensional (3D) design approach has not received adequate attention in the process of engineering practice. Based on Building Information Modeling (BIM) and Revit secondary development technology, an automatic generation construction shop design model system of MEP hanger (MEP hanger-CDM) for the quick placement of hanger components, automatic grouping of hanger components and hanger component constructability checking was developed. By conducting investigations with the construction companies and construction sites in China, four basic forms of MEP hanger layouts were identified to accommodate different types of MEP layouts. In addition, the design requirements of the family of LOD 400 BIM models were summarized along with the analysis of user requirements. The results of the case studies indicate a 70% reduction in the manpower number on the MEP hanger shop design and an 85.9% reduction in the number of working hours. Moreover, the efficiency of the hanger construction model design and the accuracy of the output of material lists and shop drawings could be improved. Thus, the process of designing MEP hanger could be optimized in a visualized method.

Three-dimensional radiographic assessment of the mandibular retromolar donor site in different vertical facial growth types

PurposeTo assess volumetrically, the impact of vertical facial growth types (VGFT) on the retromolar area as a bone donor site Material and methods60 cone beam computed tomography (CBCT) scans of adult individuals were classified in three groups according to their SN-GoGn angle: hypodivergent group (hG) (33.33%), normodivergent group (NG) (30%) and hyperdivergent group (HG) (36.67%). Total harvestable bone volume and surface (TBV and TBS respectively), total cortical and cancellous bone volume (TCBV and TcBV respectively) and the percentage of cortical and cancellous bone volume (CBV and cBV respectively) were evaluated. ResultsThe whole sample showed a mean TBV of 1220.99±448.81mm³ and a mean TBS of 940.29±259.93mm². Statistically significant differences were found between the different outcome variables and the vertical growth patterns (p<0.001). TBS differs for the different vertical growth patterns with the highest mean of TBS observed in the hG group. TBV also significantly differs between the different vertical growth patterns (p<0.001) with the highest mean observed for the hG individuals. Significant differences in percentages of cBV and CBV were present between the hyper-divergent groups and the other groups (p<0.001) with the hyper-divergent group having the lowest percentage of CBV and the highest percentage of cBV. Conclusionhypodivergent individuals tend to have thicker bone blocks that can be used in onlay technique while thinner bone blocks harvested from hyperdivergent and normodivergent individuals can be used in three-dimensional grafting approach.

The process of establishing marine spatial planning maps in Vietnam

Creating a marine spatial planning map (MSP) guides the determination of the map's extent and scale, the map, the content of the map, the methods and techniques of mapping, and the sequence of steps performed. The process consists of 5 steps: 1) Define nature, requirements, scope, and methods, 2) Analyze and evaluate data and information, 3) Make and draw thematic maps and diagrams, 4) MSP mapping, and 5) Make a description of the MSP map. MSP maps' location, scope, and scale are established according to a 3-level system: national, regional, and local. The three-dimensional approach MSP map is integrated and synthesized from the marine functional zoning and marine space use zoning maps of the same scale. The set of MSP maps in Vietnam is divided into 3 levels: national level MSP maps with a scale of 1:1,000,000; regional MSP map, scale 1:500,000 together with MSP map of sub-regions at 1:250,000 scale; local-provincial MSP maps at the scale of 1:100,000 and in case of necessity, establish district-level MSP maps at scale 1:25,000–1:50,000. Vietnam's sea is functionally divided into 5 large marine regions, including the Gulf of Tonkin. The Gulf of Tonkin (region I) is divided into 6 functional zones, including Mong Cai - Do Son one. This area is established MSP Map at scale 1:250,000 as a reference example, showing 3 functional areas and 7 basic units using marine space.

Application of Pathway Analysis Factors Affecting the Human Development Index in North Sumatra in 2021-2022

The Human Development Index (IPM) measures human development achievements based on a number of basic quality of life components. As a measure of quality of life, HDI is built through a basic three-dimensional approach. These dimensions include a long and healthy life; knowledge, and a decent life. These three dimensions have a very broad meaning because they are related to many factors. To measure the health dimension, life expectancy at birth is used. Furthermore, to measure the dimensions of knowledge, a combination of literacy rate indicators and the average length of schooling is used. This study aims to determine the relationship or influence between variables on the human development index. These variables are the average length of schooling, life expectancy, and the percentage of poor people. This research uses survey data from BPS North Sumatra for the 2021-2022 period. Data processing uses path analysis with the help of SPSS version 23 software. The path equation obtained in this study is Y = 0.672X1 + 0.297X2 − 0.223Z + 0.081. The results showed that there was a significant influence between the average length of schooling, life expectancy, and the percentage of poor people on the human development index.

Violence against Male in Abu Ghraib in The New Yorker's political Reports

The present study under the title " Violence against Male in Abu Ghraib in The New Yorker's political Reports" is interested in revealing issues of power, dominance and ideologies in the political reports which talk about violence against men in Abu Ghraib. Revealing these issues in the report will be according to the use of CDA approach depending on the two scholars who are interested in this approach, Tuen Van Dijk, Norman Fairclough. In this study, there is a use of language as a tool to express the dominance, power and ideology. With these linguistic elements, the previous issues are exploited indirectly by the American forces. &#x0D; We aim in this study to identify all the linguistic elements which symbolize violence in the selected report. Then, we will explain its function in this report which is used pragmatically. After that, we explain the issues of power, dominance and ideologies and check whether they are used in these reports implicitly or explicitly.&#x0D; We selected one report to be analysed in this paper. This report was taken from the American weekly magazine "The New Yorker". Selecting these Extracts was based on the using of many linguistic elements which refer to violence in Abu Ghraib. &#x0D; We used the qualitative approach in analyzing the data, because we deal with behavioral study, and it is the preferable approach in analyzing studies like these. In this method, we depend on the narrative way in the analysis rather than using numbers or statistics. The model adopted in this study will be eclectic one depending on Fairclough's three-dimensional approach and Van Dijk's socio-cognitive approach. These models are interested in the texts with their social and cultural function.&#x0D; The findings have included the use of linguistic elements of violence in these reports in many lines. The function of these linguistic elements was used indirectly in a hidden way. The study also revealed that issues of power, dominance and ideologies were exploited pragmatically in the American speeches. Our aims and Hypothesis have been achieved in the findings and conclusions. In the last lines of chapter five, we gave some recommendations and suggestions for further studies.

Microencapsulated Hepatocytes Differentiated from Human Induced Pluripotent Stem Cells: Optimizing 3D Culture for Tissue Engineering Applications.

Liver cell therapy and in vitro models require functional human hepatocytes, the sources of which are considerably limited. Human induced pluripotent stem cells (hiPSCs) represent a promising and unlimited source of differentiated human hepatocytes. However, when obtained in two-dimensional (2D) cultures these hepatocytes are not fully mature and functional. As three-dimensional culture conditions offer advantageous strategies for differentiation, we describe here a combination of three-dimensional (3D) approaches enabling the successful differentiation of functional hepatocytes from hiPSCs by the encapsulation of hiPSC-derived hepatoblasts in alginate beads of preformed aggregates. The resulting encapsulated and differentiated hepatocytes (E-iHep-Orgs) displayed a high level of albumin synthesis associated with the disappearance of α-fetoprotein (AFP) synthesis, thus demonstrating that the E-iHep-Orgs had reached a high level of maturation, similar to that of adult hepatocytes. Gene expression analysis by RT-PCR and immunofluorescence confirmed this maturation. Further functional assessments demonstrated their enzymatic activities, including lactate and ammonia detoxification, as well as biotransformation activities of Phase I and Phase II enzymes. This study provides proof of concept regarding the benefits of combining three-dimensional techniques (guided aggregation and microencapsulation) with liver differentiation protocols as a robust approach to generate mature and functional hepatocytes that offer a permanent and unlimited source of hepatocytes. Based on these encouraging results, our combined conditions to produce mature hepatocytes from hiPSCs could be extended to liver tissue engineering and bioartificial liver (BAL) applications at the human scale for which large biomasses are mandatory.

Mimicking exercise in vitro - effects of myotube contractions and mechanical stretch on omics.

The number of studies using skeletal muscle (SkM) cell culture models to study exercise in vitro are rapidly expanding. Progressively, more comprehensive analysis methods, such as different omics approaches including transcriptomics, proteomics and metabolomics have been used to examine the intra- and extracellular molecular responses to exercise mimicking stimuli in cultured myotubes. Among other techniques, exercise-like electrical pulse stimulation (EL-EPS) and mechanical stretch of SkM cells are the two most commonly used methods to mimic exercise in vitro. In this mini-review we focus on these two approaches and their effects on the omics of myotubes and/or cell culture media. Furthermore, besides traditional two-dimensional (2D) methods, the use of three-dimensional (3D) SkM approaches are increasing in the field of in vitro exercise mimicry. Our aim with this mini-review is to provide the reader with an up-to-date overview of the 2D and 3D models and the use of omics approaches to study the molecular response to exercise in vitro.

An observationally derived kick distribution for neutron stars in binary systems

ABSTRACT Understanding the natal kicks received by neutron stars (NSs) during formation is a critical component of modelling the evolution of massive binaries. Natal kicks are an integral input parameter for population synthesis codes, and have implications for the formation of double NS systems and their subsequent merger rates. However, many of the standard observational kick distributions that are used are obtained from samples created only from isolated NSs. Kick distributions derived in this way overestimate the intrinsic NS kick distribution. For NSs in binaries, we can only directly estimate the effect of the natal kick on the binary system, instead of the natal kick received by the NS itself. Here, for the first time, we present a binary kick distribution for NSs with low-mass companions. We compile a catalogue of 145 NSs in low-mass binaries with the best available constraints on proper motion, distance, and systemic radial velocity. For each binary, we use a three-dimensional approach to estimate its binary kick. We discuss the implications of these kicks on system formation, and provide a parametric model for the overall binary kick distribution, for use in future theoretical modelling work. We compare our results with other work on isolated NSs and NSs in binaries, finding that the NS kick distributions fit using only isolated pulsars underestimate the fraction of NSs that receive low kicks. We discuss the implications of our results on modelling double NS systems, and provide suggestions on how to use our results in future theoretical works.

Two-Dimensional Post-Traumatic Measurements of Orbital Floor Blowout Fractures Underestimate Defect Sizes Compared to Three-Dimensional Approaches

Orbital floor fractures represent a common fracture type of the midface and are standardly diagnosed clinically as well as radiologically using linear measurement methods. The aim of this study was to evaluate the accuracy of diagnostic measurements of isolated orbital floor fractures based on two-dimensional (2D) and three-dimensional (3D) measurement techniques. A cohort of 177 patients was retrospectively and multi-centrically evaluated after surgical treatment of an orbital floor fracture between 2010 and 2020. In addition to 2D and 3D measurements of the fracture area, further fracture-related parameters were investigated. Calculated fracture areas using the 2D measurement technique revealed an average area of 287.59 mm2, whereas the 3D measurement showed fracture areas with a significantly larger average value of 374.16 mm2 (p < 0.001). On average, the 3D measurements were 1.53-fold larger compared to the 2D measurements. This was observed in 145 patients, whereas only 32 patients showed smaller values in the 3D-based approach. However, the process duration of the 3D measurement took approximately twice as long as the 2D-based procedure. Nonetheless, 3D-based measurement of orbital floor defects provides a more accurate estimation of the fracture area than the 2D-based procedure and can be helpful in determining the indication and planning the surgical procedure.

3D printing-based full-scale human brain for diverse applications.

Surgery is the most frequent treatment for patients with brain tumors. The construction of full-scale human brain models, which is still challenging to realize via current manufacturing techniques, can effectively train surgeons before brain tumor surgeries. This paper aims to develop a set of three-dimensional (3D) printing approaches to fabricate customized full-scale human brain models for surgery training as well as specialized brain patches for wound healing after surgery. First, a brain patch designed to fit a wound's shape and size can be easily printed in and collected from a stimuli-responsive yield-stress support bath. Then, an inverse 3D printing strategy, called "peeling-boiled-eggs," is proposed to fabricate full-scale human brain models. In this strategy, the contour layer of a brain model is printed using a sacrificial ink to envelop the target brain core within a photocurable yield-stress support bath. After crosslinking the contour layer, the as-printed model can be harvested from the bath to photo crosslink the brain core, which can be eventually released by liquefying the contour layer. Both the brain patch and full-scale human brain model are successfully printed to mimic the scenario of wound healing after removing a brain tumor, validating the effectiveness of the proposed 3D printing approaches.

Multiscale Finite-Element Analysis of Damage Behavior of Curved Ramp Bridge Deck Pavement Considering Tire–Bridge Interaction Effect

The present study developed a three-dimensional (3D) multiscale modeling approach to investigate the mesoscale damage behavior of curved ramp bridge deck pavement subjected to tire loading. First, a full-scale tire–bridge interaction finite element (FE) model was established to solve the macroscopic response of deck pavement during vehicle turning. Subsequently, the 3D mesostructure of the asphalt concrete layer was reconstructed from X-ray computer tomography (CT) images through a digital image processing (DIP) technology. Finally, a homogenization method was adopted to link the mechanical properties of deck pavement at two different scales, and a mapping procedure was employed to transfer the boundary displacements from macroscale pavement target element to the mesoscale representative volume element (RVE) model. Also, the bilinear cohesive elements were applied to simulate damage initiation in the RVEs. The results showed that smaller curvature radius and higher travel speed can promote unbalanced stress and local damage of the outer loading zone. From the mesoscale viewpoint, reducing curvature radius or increasing travel speed could result in crack direction shifts and increase the irregularity of microcrack distribution. In addition, transverse microcracks are commonly found in the center of the tire load, while longitudinal microcracks are distributed on the deck pavement surface around the tire edges and the dual-tire clearance center.

Carbon footprint of the analytical laboratory and the three-dimensional approach to its reduction

Carbon footprint of the analytical laboratory and the three-dimensional approach to its reduction

Notch Signaling Pathway in Tooth Shape Variations throughout Evolution.

Evolutionary changes in vertebrates are linked to genetic alterations that often affect tooth crown shape, which is a criterion of speciation events. The Notch pathway is highly conserved between species and controls morphogenetic processes in most developing organs, including teeth. Epithelial loss of the Notch-ligand Jagged1 in developing mouse molars affects the location, size and interconnections of their cusps that lead to minor tooth crown shape modifications convergent to those observed along Muridae evolution. RNA sequencing analysis revealed that these alterations are due to the modulation of more than 2000 genes and that Notch signaling is a hub for significant morphogenetic networks, such as Wnts and Fibroblast Growth Factors. The modeling of these tooth crown changes in mutant mice, via a three-dimensional metamorphosis approach, allowed prediction of how Jagged1-associated mutations in humans could affect the morphology of their teeth. These results shed new light on Notch/Jagged1-mediated signaling as one of the crucial components for dental variations in evolution.

Exploration of three-dimensional spatial learning approach based on machine learning–taking Taihu stone as an example

Under the influence of globalization, the transformation of traditional architectural space is vital to the growth of local architecture. As an important spatial element of traditional gardens, Taihu stone has the image qualities of being “thin, wrinkled, leaky and transparent” The “transparency” and “ leaky” of Taihu stone reflect the connectivity and irregularity of Taihu stone’s holes, which are consistent with the contemporary architectural design concepts of fluid space and transparency. Nonetheless, relatively few theoretical studies have been conducted on the spatial analysis and design transformation of Taihu stone. Using machine learning, we attempt to extract the three-dimensional spatial variation pattern of Taihu stone in this paper. This study extracts 3D spatial features for experiments using artificial neural networks (ANN) and generative adversarial networks (GAN). In order to extract 3D spatial variation patterns, the machine learning model learns the variation patterns between adjacent sections. The trained machine learning model is capable of generating a series of spatial sections with the spatial variation pattern of the Taihu stone. The purpose of the experimental results is to compare the performance of various machine learning models for 3D space learning in order to identify a model with superior performance. This paper also presents a novel concept for machine learning to master continuous 3D spatial features.

Modernisation of a Country in the Context of Social Environmental Sustainability: Example of Lithuania

This paper seeks to encourage deeper scientific discussions about the country’s modernisation in the context of social environmental sustainability. Emphasizing the importance of this study, the research problem was identified in response to the questions of how the country’s modernisation manifests itself in the context of social environment sustainability and what are the consequences for the society. This paper is based on a quantitative empirical study to support the structural perspective of the modernisation of the country, to develop an integrated system of indicators for the formation of a modern country following an analysis of the country’s modernisation trends in terms of the social environment. The scientific value of the study: the present paper investigates the ‘soft’ determinants of social environmental sustainability of the country; provides a methodological framework for the methods used (descriptive statistics, confirmatory factor analysis (CFA) and structural equation modelling (SEM). A three-dimensional research approach, covering the education system and educational culture; socio-economic integration; the legal system and the importance of public administration and citizenship, was utilized. A cross-sectional survey of 1021 respondents and structural equation modelling were selected as the main research tools. Lithuania served as an empirical basis for the research. It was revealed that the most important factors in shaping the modernisation of the country through the lens of social environmental sustainability are the participation of citizens in social communities and social activities. Factors that need improvement are public participation and tolerance for the disabled.

Addressing Nanocomposite Systems via 3D-SCFT: Assessment of Smearing Approximation and Irregular Grafting Distributions

We develop a three-dimensional self-consistent field-theoretic approach (3D-SCFT) for polymer matrix nanocomposites of arbitrary geometries, e.g., polymer-grafted nanoparticles (PGNPs), polymer brushes, and particle solids. The spatio-temporal discretization of Edwards’s diffusion equation is realized with the finite element method (FEM). Unidimensional implementations for PGNPs (1D-SCFT) invoke the smearing approximation (SA), which treats the grafting points as being delocalized across a spherical shell. By conducting detailed comparisons between 1D-SCFT and 3D-SCFT, we assess the accuracy of the SA in terms of reproducing key structural and thermodynamic properties of dilute grafted silica/polystyrene NPs in molten polystyrene. The SA yields accurate radially averaged structural features such as the mean brush thickness and its scaling with grafting density, chain length, and particle size. The free energy is reproduced accurately as well, albeit noticeable deviations are observed when transitioning toward the mushroom regime. In the SA, the stretching free energy is a function of the radial distance of the free end of a grafted chain from the particle surface. In 3D-SCFT, the grafting points are fixed in space, and thus chain stretching is described more accurately. 3D-SCFT offers direct access to the spatial distribution of the segment density of a chain and affords detailed visualization of the mushroom-to-dense brush transition, at the levels of both the whole system and individual grafted chains. By taking advantage of the single-chain representation in 3D-SCFT, we explore NPs with arbitrary grafting distributions (e.g., rings, tadpoles, and dual-poles) and the corresponding variation of the free energy and structural properties. To the best of the authors’ knowledge, this is the first time that the grafting distribution is examined as an additional degree of freedom in a 3D field-theoretic framework. Our work constitutes a step toward the computational design of nanocomposites with tailor-made self-assembly properties, achieved by controlling the interactions of nanoparticles through modulation of the distribution of points of attachment of grafted chains on their surface (e.g., Janus particles).

Higher-order models for the passive damping analysis of variable-angle-tow composite plates

In this paper, the damped free-vibration and frequency response analysis of variable-angle-tow composite plates embedding viscoelastic layers with frequency-dependent properties are performed. The governing equations are derived from the Principle of Virtual Displacements and higher-order Layer-Wise models are used for the unknown variables description in the thickness direction, furthermore a nine-node finite plate element is employed to solve them. The plate formulation presented in this paper is more efficient with respect to three-dimensional approaches, typically used for this kind of structures, and it is more accurate than existing reduced order methods thanks to the use of the mixed interpolation of tensorial components technique, employed to solve the problem of the shear and membrane locking phenomena. Different multilayered structures have been considered, laminated with unidirectional cross-ply layers or with curvilinear fibers path ones. The use of viscoelastic soft sheets permits to have a passive damping of the structural vibration. The frequency dependent properties of the viscoelastic materials are described through the use of a Kelvin-Voigt model. Numerical solutions are presented for the analysis of variable-angle-tow composites with different boundary-conditions and various lamination schemes.