scholarly journals Printing In Three Dimensions

2001 ◽  
Vol 123 (05) ◽  
pp. 58-60 ◽  
Author(s):  
Jean Thilmany
Keyword(s):  
Three Dimensional ◽  
Physical Models ◽  
Three Dimensions ◽  
Digital Archive ◽  
3D Printer ◽  
Vehicle Engineering ◽  
3D Cad ◽  
Hard Time ◽  
Entire Vehicle

This article discusses that a starch printer, commonly referred to as a three-dimensional printer, serves as a way to make physical models from 3D CAD files. The rapid engineering and 3D printing methods are frequently used in conjunction with a host of compatible technologies, notably a scanning technology that brings physical objects—including items produced by a 3D printer—back into the digital realm. Engineers make use of this form of scanning technology to digitize a complex item that they would have a hard time reverse engineering any other way. Others might use it to digitize 3D artwork such as sculptures to capture a long-term, digital archive of important cultural artifacts. Rapid prototyping at DaimlerChrysler takes place in the vehicle engineering operations mock-up department, among other places. The group builds physical models of parts for the engineers who designed them. Models might range from an individual part to a full-scale mock-up of the entire vehicle.

scholarly journals Design and implementation of a three dimensions (3D) printer for modeling and pre-manufacturing applications

2019 ◽  
Vol 9 (6) ◽  
pp. 4749
Author(s):  
Ghazi Qaryouti ◽  
Abdel Rahman Salbad ◽  
Sohaib A. Tamimi ◽  
Anwar Almofleh ◽  
Wael A. Salah ◽  
...  
Keyword(s):  
3D Printing ◽  
Manufacturing Sector ◽  
Low Cost ◽  
Three Dimensional ◽  
Three Dimensions ◽  
3D Printer ◽  
Overall Design ◽  
Design And Implementation ◽  
Manufacturing Applications ◽  
Functional Components

The three-dimensional (3D) printing technologies represent a revolution in the manufacturing sector due to their unique characteristics. These printers arecapable to increase the productivitywithlower complexity in addition tothe reduction inmaterial waste as well the overall design cost prior large scalemanufacturing.However, the applications of 3D printing technologies for the manufacture of functional components or devices remain an almost unexplored field due to their high complexity. In this paper the development of 3D printing technologies for the manufacture of functional parts and devices for different applications is presented. The use of 3D printing technologies in these applicationsis widelyused in modelingdevices usually involves expensive materials such as ceramics or compounds. The recent advances in the implementation of 3D printing with the use of environmental friendly materialsin addition to the advantages ofhighperformance and flexibility. The design and implementation of relatively low-cost and efficient 3D printer is presented. The developed prototype was successfully operated with satisfactory operated as shown from the printed samples shown.

scholarly journals A systematic study of proto-neutron star convection in three-dimensional core-collapse supernova simulations

2020 ◽  
Vol 492 (4) ◽  
pp. 5764-5779 ◽  
Author(s):  
Hiroki Nagakura ◽  
Adam Burrows ◽  
David Radice ◽  
David Vartanyan
Keyword(s):  
Neutron Star ◽  
Systematic Study ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Core Collapse ◽  
Core Collapse Supernova ◽  
Tau Neutrinos ◽  
The Impact ◽  
Proto Neutron Star

ABSTRACT This paper presents the first systematic study of proto-neutron star (PNS) convection in three dimensions (3D) based on our latest numerical fornax models of core-collapse supernova (CCSN). We confirm that PNS convection commonly occurs, and then quantify the basic physical characteristics of the convection. By virtue of the large number of long-term models, the diversity of PNS convective behaviour emerges. We find that the vigour of PNS convection is not correlated with CCSN dynamics at large radii, but rather with the mass of PNS − heavier masses are associated with stronger PNS convection. We find that PNS convection boosts the luminosities of νμ, ντ, $\bar{\nu }_{\mu }$, and $\bar{\nu }_{\tau }$ neutrinos, while the impact on other species is complex due to a competition of factors. Finally, we assess the consequent impact on CCSN dynamics and the potential for PNS convection to generate pulsar magnetic fields.

scholarly journals Elements for the Successful Computer Simulation of Sediment Management Strategies for Reservoirs

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 714 ◽  
Author(s):  
Razieh Anari ◽  
Rollin H. Hotchkiss ◽  
Eddy Langendoen
Keyword(s):  
Computer Simulation ◽  
Management Strategies ◽  
Three Dimensional ◽  
Sediment Management ◽  
Three Dimensions ◽  
Density Currents ◽  
Local Pressure ◽  
Reservoir Sediment ◽  
Computer Codes

Computer simulation of reservoir sediment management strategies is becoming more important as worldwide water supply shrinks due to sediment deposition, while population growth continues. We identified the physical processes underlying each of the several alternatives available to transport incoming or deposited sediments downstream into receiving waters and the governing equations that describe each process. The purpose of this paper is to understand how physical characteristics of reservoir sediment management can be simulated with available computer codes. We described commonly available computer codes and their abilities to solve the appropriate equations in one, two, or three dimensions. The results revealed that one dimensional models are most appropriate for long-term simulations of the evolving reservoir bottom profile, while two or three dimensional codes are more appropriate for simulating density currents and detailed lateral movement of sediments, such as during local pressure flushing near reservoir outlets. We conclude that existing codes can successfully simulate sediment management, but because each code has limitations, they require seasoned judgment in their choice, application, and interpretation. Incorporating sediment prediction and management correctly into the planning, design, and operational phases of dam projects is essential for ensuring that the benefits of reservoir storage are sustained over the long term. The implications of our key findings are that sediment management strategies can be successfully simulated and that such simulations should be performed for our aging dams and newly proposed projects.

scholarly journals Investigation of Patient-Specific Maxillofacial Implant Prototype Development by Metal Fused Filament Fabrication (MF3) of Ti-6Al-4V

2021 ◽  
Vol 9 (10) ◽  
pp. 109
Author(s):  
Mohammad Qasim Shaikh ◽  
Subrata Deb Nath ◽  
Arulselvan Arumugam Akilan ◽  
Saleh Khanjar ◽  
Vamsi Krishna Balla ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Image Data ◽  
Total Porosity ◽  
Physical Models ◽  
Patient Specific ◽  
Fused Filament Fabrication ◽  
3D Cad ◽  
Prototype Development ◽  
Cad Models ◽  
First Time

Additive manufacturing (AM) and related digital technologies have enabled several advanced solutions in medicine and dentistry, in particular, the design and fabrication of patient-specific implants. In this study, the feasibility of metal fused filament fabrication (MF3) to manufacture patient-specific maxillofacial implants is investigated. Here, the design and fabrication of a maxillofacial implant prototype in Ti-6Al-4V using MF3 is reported for the first time. The cone-beam computed tomography (CBCT) image data of the patient’s oral anatomy was digitally processed to design a 3D CAD model of the hard tissue and fabricate a physical model by stereolithography (SLA). Using the digital and physical models, bone loss condition was analyzed, and a maxillofacial implant initial design was identified. Three-dimensional (3D) CAD models of the implant prototypes were designed that match the patient’s anatomy and dental implant requirement. In this preliminary stage, the CAD models of the prototypes were designed in a simplified form. MF3 printing of the prototypes was simulated to investigate potential deformation and residual stresses. The patient-specific implant prototypes were fabricated by MF3 printing followed by debinding and sintering using a support structure for the first time. MF3 printed green part dimensions fairly matched with simulation prediction. Sintered parts were characterized for surface integrity after cutting the support structures off. An overall 18 ± 2% shrinkage was observed in the sintered parts relative to the green parts. A relative density of 81 ± 4% indicated 19% total porosity including 11% open interconnected porosity in the sintered parts, which would favor bone healing and high osteointegration in the metallic implants. The surface roughness of Ra: 18 ± 5 µm and a Rockwell hardness of 6.5 ± 0.8 HRC were observed. The outcome of the work can be leveraged to further investigate the potential of MF3 to manufacture patient-specific custom implants out of Ti-6Al-4V.

scholarly journals The Virtues of Virtual Products

1998 ◽  
Vol 120 (06) ◽  
pp. 60-63 ◽  
Author(s):  
Steve Ghee
Keyword(s):  
Computer Aided Design ◽  
Three Dimensional ◽  
Wide Distribution ◽  
Physical Models ◽  
Time Interaction ◽  
Interactive Product ◽  
Time Distance ◽  
High Level ◽  
Aided Design

Manufacturing and engineering companies around the world are building virtual products that can communicate across the barriers of time, distance, discipline, and culture. Interactive-product-simulation (IPS) technology complements the processes used to create three-dimensional geometry. IPS software leverages a company's investment in computer-aided design (CAD) design by providing earlier access to prototypes, faster updates than with physical models, enterprise-wide distribution of information in an easy-to-understand format, support for existing processes, and long-term value that extends beyond the finalization of product designs. IPS provides real-time interaction via the virtual product-a simulated version of the final functioning design that can include functional simulations, animations, mechanisms, and simulated humans or ‘manikins.’ IPS has many applications in the concept phase, where one of the most critical challenges for manufacturers is the economic evaluation and frequent review of multiple high-level concepts and configurations. PS enables engineers, manufacturing and maintenance staff, and even customers to visualize and operate complex virtual products so that they can improve the designs' manufacturability, ergonomics, and maintainability.

Long-Term Effects of Nasoalveolar Molding on Three-Dimensional Nasal Shape in Unilateral Clefts

1999 ◽  
Vol 36 (5) ◽  
pp. 391-397 ◽  
Author(s):  
Deirdre J. Maull ◽  
Barry H. Grayson ◽  
Court B. Cutting ◽  
Larry L. Brecht ◽  
Fred L. Bookstein ◽  
...  
Keyword(s):  
New York ◽  
Medical Center ◽  
Three Dimensional ◽  
Asymmetry Index ◽  
Mirror Image ◽  
Three Dimensions ◽  
Control Group ◽  
Long Term Effects ◽  
Nasoalveolar Molding

Objective: This objective of this study was to determine the effect of presurgical nasoalveolar molding on long-term nasal shape in complete unilateral clefts. Design: The study was retrospective, and the subjects were chosen at random. Nasal casts of the subjects were scanned in three dimensions. Each nose was best fit to its mirror image, and a numerical asymmetry score was determined. Setting: All patients were treated at the Institute of Reconstructive Plastic Surgery, NYU Medical Center, New York, New York. Patients: The study subjects (n = 10) were selected from a group that had undergone presurgical nasal molding in conjunction with alveolar molding. The control subjects (n = 10) were selected from a group that had undergone presurgical alveolar molding alone. Interventions: All subjects underwent presurgical orthopedic treatment until the age of approximately 4 months at which time the primary surgery was performed. Main Outcome Measure: The nasal shape following nasal molding should be more symmetrical than if molding had not been done. Results: The mean asymmetry index for the nasoalveolar molding group was 0.74, and the control group was 1.21. This difference was statistically significant (p < .05). Conclusions: Presurgical nasoalveolar molding significantly increases the symmetry of the nose. The increase in symmetry is maintained long term into early childhood. The limitations of this study include (1) asymmetry alone is not an adequate shape result in most situations, (2) the children evaluated in this study were not fully grown, and (3) the control group was not age matched.

Practical electron tomography

1995 ◽  
Vol 53 ◽  
pp. 742-743
Author(s):  
C.L. Woodcock
Keyword(s):  
Electron Tomography ◽  
Tomographic Reconstruction ◽  
Three Dimensional ◽  
3D Shape ◽  
Computational Resources ◽  
Shape Of Particles

Despite the potential of the technique, electron tomography has yet to be widely used by biologists. This is in part related to the rather daunting list of equipment and expertise that are required. Thanks to continuing advances in theory and instrumentation, tomography is now more feasible for the non-specialist. One barrier that has essentially disappeared is the expense of computational resources. In view of this progress, it is time to give more attention to practical issues that need to be considered when embarking on a tomographic project. The following recommendations and comments are derived from experience gained during two long-term collaborative projects.Tomographic reconstruction results in a three dimensional description of an individual EM specimen, most commonly a section, and is therefore applicable to problems in which ultrastructural details within the thickness of the specimen are obscured in single micrographs. Information that can be recovered using tomography includes the 3D shape of particles, and the arrangement and dispostion of overlapping fibrous and membranous structures.

convergent-beam diffraction from surfaces

1987 ◽  
Vol 45 ◽  
pp. 30-33
Author(s):  
J. A. Eades ◽  
A. E. Smith ◽  
D. F. Lynch
Keyword(s):  
Reciprocal Lattice ◽  
Three Dimensional ◽  
Grazing Incidence ◽  
Three Dimensions ◽  
Plane Figure ◽  
Transmission Electron ◽  
Convergent Beam ◽  
Beam Patterns ◽  
Beam Diffraction

It is quite simple (in the transmission electron microscope) to obtain convergent-beam patterns from the surface of a bulk crystal. The beam is focussed onto the surface at near grazing incidence (figure 1) and if the surface is flat the appropriate pattern is obtained in the diffraction plane (figure 2). Such patterns are potentially valuable for the characterization of surfaces just as normal convergent-beam patterns are valuable for the characterization of crystals.There are, however, several important ways in which reflection diffraction from surfaces differs from the more familiar electron diffraction in transmission.GeometryIn reflection diffraction, because of the surface, it is not possible to describe the specimen as periodic in three dimensions, nor is it possible to associate diffraction with a conventional three-dimensional reciprocal lattice.

Custom Presurgical Planning for Midfacial Reconstruction

2020 ◽  
Vol 36 (06) ◽  
pp. 696-702
Author(s):  
Nolan B. Seim ◽  
Enver Ozer ◽  
Sasha Valentin ◽  
Amit Agrawal ◽  
Mead VanPutten ◽  
...  
Keyword(s):  
Multidisciplinary Approach ◽  
Functional Performance ◽  
Three Dimensional ◽  
Free Tissue Transfer ◽  
Long Term Effects ◽  
Presurgical Planning ◽  
Dental Rehabilitation ◽  
Midface Reconstruction ◽  
Reconstructive Algorithm

AbstractResection and reconstruction of midface involve complex ablative and reconstructive tools in head and oncology and maxillofacial prosthodontics. This region is extraordinarily important for long-term aesthetic and functional performance. From a reconstructive standpoint, this region has always been known to present challenges to a reconstructive surgeon due to the complex three-dimensional anatomy, the variable defects created, combination of the medical and dental functionalities, and the distance from reliable donor vessels for free tissue transfer. Another challenge one faces is the unique features of each individual resection defect as well as individual patient factors making each preoperative planning session and reconstruction unique. Understanding the long-term effects on speech, swallowing, and vision, one should routinely utilize a multidisciplinary approach to resection and reconstruction, including head and neck reconstructive surgeons, prosthodontists, speech language pathologists, oculoplastic surgeons, dentists, and/or craniofacial teams as indicated and with each practice pattern. With this in mind, we present our planning and reconstructive algorithm in midface reconstruction, including a dedicated focus on dental rehabilitation via custom presurgical planning.

Extension of the Spatial PDI Model to Three Dimensions

1997 ◽  
Vol 84 (1) ◽  
pp. 176-178
Author(s):  
Frank O'Brien
Keyword(s):  
Population Density ◽  
Dimensional Space ◽  
Finite Lattice ◽  
Three Dimensional ◽  
Upper Bounds ◽  
Three Dimensions ◽  
Lower And Upper Bounds ◽  
Density Index ◽  
Three Dimensional Space

The author's population density index ( PDI) model is extended to three-dimensional distributions. A derived formula is presented that allows for the calculation of the lower and upper bounds of density in three-dimensional space for any finite lattice.

Sign in / Sign up

Export Citation Format

Share Document