Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
73,480
result(s) for
"Three dimensional models"
Sort by:
Learn Autodesk Inventor 2018 basics : 3D modeling, 2D graphics, and assembly design
\"Get started with the basics of part modeling, assembly modeling, presentations, and drawings in this step-by-step tutorial on Autodesk Inventor fundamentals. Next, this book teaches you some intermediate-level topics such as additional part modeling tools, sheet metal modeling, top-down assembly features, assembly joints, and dimension and annotations. Engaging explanations, practical examples, and step-by-step instructions make this tutorial book complete. Once you have read Learn Autodesk Inventor 2018 Basics you will be able to use Autodesk Inventor for 3D modeling, 2D drawings, finite element analysis, mold design, and other purposes, just like a design professional. You will gain all the basic information and essential skills you need to work in Autodesk Inventor immediately. You will: Carry out virtual 3D modeling for your next 3D printing projects Design molds for 3D printing and other projects Generate 2D drawings Apply basic finite element analysis for figuring stress, tension, and optimized dimensions for your 3D printing projects\"--Page [4] of cover.
Book
Slab2, a comprehensive subduction zone geometry model
Subduction zones are responsible for the most-damaging and tsunami-generating great earthquakes. Hayes
et al.
updated their Slab1.0 model to include all seismically active subduction zones, including geometrically complex regions like the Philippines. The new model, Slab2, details the geometry of 24 million square kilometers of subducted slabs, from ocean trench to upper mantle. The model will be vital for fully understanding seismic hazard in some of the most populated regions in the world.
Science
, this issue p.
58
Slab2 is a comprehensive model of all seismically active subduction zones on Earth.
Subduction zones are home to the most seismically active faults on the planet. The shallow megathrust interfaces of subduction zones host Earth’s largest earthquakes and are likely the only faults capable of magnitude 9+ ruptures. Despite these facts, our knowledge of subduction zone geometry—which likely plays a key role in determining the spatial extent and ultimately the size of subduction zone earthquakes—is incomplete. We calculated the three-dimensional geometries of all seismically active global subduction zones. The resulting model, called Slab2, provides a uniform geometrical analysis of all currently subducting slabs.
Journal Article
Digital modelmaking : laser cutting, 3D printing and reverse engineering
Digital manufacturing has become an intrinsic part of the modelmaking profession, so today's practitioner must be skilled in both traditional hand-making techniques and digital technology. Relevant to a wide variety of creative industries, including film and television, theatre, architecture and product design, Digital Modelmaking offers a comprehensive insight into the manufacturing processes and technologies used within contemporary modelmaking. Each chapter contains an in-depth explanation of each topic, presents examples of how each process is used and includes case studies from professional modelmakers and students. Topics covered include: making models using a laser cutter, 3D printer and CNC milling machinery; generating 3D digital data using a 3D scanner and photogrammetry; two-and three- dimensional drawing software such as CAD; designing models for digital manufacturing; selecting materials based on their suitability for modelmaking; combining traditional hand-making skills with digital manufacturing; painting and finishing models, and finally, moulding and casting using silicone and resin. This invaluable book will be of great interest for students, young professionals and everyone with a passion for design and making. It is superbly illustrated with 234 colour photographs and 32 line artworks giving numerous examples of the design process. Helen Lansdown has worked professionally as a modelmaker and designer for thirty years and is a lecturer at Herefordshire University teaching on the Model Design programme.
Book
A three-dimensional nonlinear rock damage creep model with double damage factors and residual strength
Creep failure behavior of rock is the focus of research on rock rheology and affects the stability and safety of slopes and underground structure. Based on continuous damage mechanics and the physical damage mechanism, double variables of time-dependent damages are defined here to further investigate the creep behaviors of rock. A new viscoelastic-plastic damage element and residual strength correction factor are first introduced to construct a novel double damage factor for the creep constitutive model. Furthermore, three-dimensional creep equations are derived for considering the yield criterion, plastic potential function, and flow law. Finally, the experimental data and the Burgers model have conducted a series of validations on the proposed model. Results show that the model proposed here can accurately capture the creep characteristics of rock, especially in simulating accelerated creep. The proposed model is more advantageous than the Burgers model and provides some reference for practical engineering design and safety monitoring.
Journal Article
Evaluating models and assessment techniques for understanding oral biofilm complexity
Oral biofilms are three‐dimensional (3D) complex entities initiating dental diseases and have been evaluated extensively in the scientific literature using several biofilm models and assessment techniques. The list of biofilm models and assessment techniques may overwhelm a novice biofilm researcher. This narrative review aims to summarize the existing literature on biofilm models and assessment techniques, providing additional information on selecting an appropriate model and corresponding assessment techniques, which may be useful as a guide to the beginner biofilm investigator and as a refresher to experienced researchers. The review addresses previously established 2D models, outlining their advantages and limitations based on the growth environment, availability of nutrients, and the number of bacterial species, while also exploring novel 3D biofilm models. The growth of biofilms on clinically relevant 3D models, particularly melt electrowritten fibrous scaffolds, is discussed with a specific focus that has not been previously reported. Relevant studies on validated oral microcosm models that have recently gaining prominence are summarized. The review analyses the advantages and limitations of biofilm assessment methods, including colony forming unit culture, crystal violet, 2,3‐bis‐(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium‐5‐carboxanilide inner salt assays, confocal microscopy, fluorescence in situ hybridization, scanning electron microscopy, quantitative polymerase chain reaction, and next‐generation sequencing. The use of more complex models with advanced assessment methodologies, subject to the availability of equipment/facilities, may help in developing clinically relevant biofilms and answering appropriate research questions.
This review focuses on diverse biofilm models and assessment strategies, highlighting the transition in the field from two‐dimensional models to the recently explored novel three‐dimensional models that aim to mimic biofilm development in the microenvironment of biological structures. The review further explores culture‐dependent biofilm assessment strategies such as colony‐forming unit assay, crystal violet assay, 2,3‐bis‐(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium‐5‐carboxanilide inner salt (XTT) assay, and imaging techniques, as well as the culture‐independent approach of next‐generation sequencing.
Journal Article
Description of a complex, rainfall-induced landslide within a multi-stage three-dimensional model
The mechanical processes involved in movements of earth or rock masses under the effect of gravity—a landslide—may include several phases where the failure of one portion of terrain can lead to the instability of the surrounding parts. An earlier landslide might have follow-up landslides until the landscape finds the equilibrium state. Recurring landslides are often recorded in landslide inventories but the information is seldom exploited in physical landslide modeling. Here, we study the landslide mechanism using Scoops3D—a three-dimensional, physically based landslide model. The program employs the three-dimensional column limit equilibrium and a digital elevation model to perform a slope stability analysis. Scoops3D evaluates the stability of rotational, spherical slip surfaces encompassing many grid cells, and finds the least-stable sliding surface throughout the entire digital landscape. The program generates two important outputs, namely a factor of safety map and a terrain map showing the new topographical conditions of the site with unstable areas removed. To define the final predicted landslide boundary, we have run Scoops3D repeatedly to assess the site’s stability using a newly produced terrain profile until the model predicts as stable all of the grid cells within the entire landscape. We compared the method's prediction with the actual sliding scar that took place on August 05, 2019, following a historical rainstorm in Sapa-Vietnam. Results for modified success rate, a performance metric, show that with reliable input data, the approach can predict the evolution of landslides with improved results compared to the traditional method using Scoops3D.
Journal Article
3D modeling of different areas of China based on the 3D Surface Spline model
This study creates a three-dimensional surface spline (3DSS) model of mainland China based on surface and CHAMP satellite observations. Through this model, the magnetic field analyses of domestic plateau (Qinghai-Tibet Plateau 28°N–38°N, 78°E–102°E), plain (middle and lower reaches of Yangtze River Plain 27°N–34°N, 111°E–122°E), and marine (parts of the East and South China Seas 16°N–30°N, 123°E–136°E) areas have been investigated. Single models of plateau and plain have also been created. To compare and verify results, the corresponding two-dimensional (2DTY) and three-dimensional (3DTY) Taylor polynomial models have been derived. Issues such as the removal of disturbing geomagnetic fields, the data gap between surface and satellite level, and boundary effect are all seriously considered. With an aim to evaluate the resulting model, some randomly selected points are not join the modeling, by which we thereby inspected the results in terms of residuals, change rate absolutes, and Root Mean Square Error (RMSE). Results show that except component Y, the change rate absolutes of other components are less than 1% both in domestic and single models, which means that the modeling result of 3DSS is better than the other two models. Plateau and plain 3DSS models reflect the fine distribution of the magnetic field after comparison with domestic distribution. The 3DSS model fits the plateau best, followed by the plain, while the worst fit is in the marine area. This means that the modeling precision depends mainly on the number and distribution of measuring points.
Journal Article
Whale Algorithm for Schedule Optimization of Construction Projects Employing Building Information Modeling
ABSTRACT
This study introduces a new approach by applying the Whale Optimization Algorithm (WOA) to create construction schedules using geometric data from Building Information Modeling (BIM). The algorithm utilizes 3D model information to establish stability criteria, which are organized in a Directed Design Structure Matrix (DSM). These criteria are integrated into the WOA Fitness function to enhance the constructability of schedules, where each schedule is symbolized as a unique whale. Through iterative WOA computations, the approach consistently achieves maximum constructability scores starting from randomly generated schedules, affirming the efficacy of this method. The results reveal that the proposed algorithm effectively produced fully executable project schedules from diverse inputs. Despite variations in computational times due to different input parameters, the experiments verified the consistent generation of schedules that are 100% executable.
The entire process of whale optimization method for the current problem is summarized in the graphical image.
Journal Article
Locality-based 3-D multiple-point statistics reconstruction using 2-D geological cross sections
Multiple-point statistics (MPS) has shown promise in
representing complicated subsurface structures. For a practical
three-dimensional (3-D) application, however, one of the critical issues is
the difficulty in obtaining a credible 3-D training image. However,
bidimensional (2-D) training images are often available because established
workflows exist to derive 2-D sections from scattered boreholes and/or other
samples. In this work, we propose a locality-based MPS approach to
reconstruct 3-D geological models on the basis of such 2-D cross sections (3DRCS),
making 3-D training images unnecessary. Only several local
training subsections closer to the central uninformed node are used in the
MPS simulation. The main advantages of this partitioned search strategy are
the high computational efficiency and a relaxation of the stationarity
assumption. We embed this strategy into a standard MPS framework. Two
probability aggregation formulas and their combinations are used to assemble
the probability density functions (PDFs) from different subsections.
Moreover, a novel strategy is adopted to capture more stable PDFs, where the
distances between patterns and flexible neighborhoods are integrated on
multiple grids. A series of sensitivity analyses demonstrate the
stability of the proposed approach. Several hydrogeological 3-D application
examples illustrate the applicability of the 3DRCS approach in reproducing
complex geological features. The results, in comparison with previous MPS
methods, show better performance in portraying anisotropy characteristics
and in CPU cost.
Journal Article
Impacts of 25 years of groundwater extraction on subsidence in the Mekong delta, Vietnam
Many major river deltas in the world are subsiding and consequently become increasingly vulnerable to flooding and storm surges, salinization and permanent inundation. For the Mekong Delta, annual subsidence rates up to several centimetres have been reported. Excessive groundwater extraction is suggested as the main driver. As groundwater levels drop, subsidence is induced through aquifer compaction. Over the past 25 years, groundwater exploitation has increased dramatically, transforming the delta from an almost undisturbed hydrogeological state to a situation with increasing aquifer depletion. Yet the exact contribution of groundwater exploitation to subsidence in the Mekong delta has remained unknown. In this study we deployed a delta-wide modelling approach, comprising a 3D hydrogeological model with an integrated subsidence module. This provides a quantitative spatially-explicit assessment of groundwater extraction-induced subsidence for the entire Mekong delta since the start of widespread overexploitation of the groundwater reserves. We find that subsidence related to groundwater extraction has gradually increased in the past decades with highest sinking rates at present. During the past 25 years, the delta sank on average ∼18 cm as a consequence of groundwater withdrawal. Current average subsidence rates due to groundwater extraction in our best estimate model amount to 1.1 cm yr−1, with areas subsiding over 2.5 cm yr−1, outpacing global sea level rise almost by an order of magnitude. Given the increasing trends in groundwater demand in the delta, the current rates are likely to increase in the near future.
Journal Article