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Optimizing supports for additive manufacturing

Grégoire Allaire, Beniamin Bogosel
2018 Structural And Multidisciplinary Optimization  
Our optimization algorithm is based on the level set method and on the computation of shape derivatives by the Hadamard method.  ...  In this article we present mathematical models and their numerical implementations in an optimization loop, which allow us to design optimal support structures.  ...  Acknowledgements This work was partially supported by the SOFIA project, funded by BPI (Banque Publique d'Investissement). G.A. is a member of the DEFI project at INRIA Saclay Ile-de-France.  ... 
doi:10.1007/s00158-018-2125-x fatcat:kvu2v3jyurc47d7yv6jddeuddi

Computing medial axes of generic 3D regions bounded by B-spline surfaces

Suraj Musuvathy, Elaine Cohen, James Damon
2011 Computer-Aided Design  
Evolution of the (self-) intersection set is computed by adapting a method for tracking intersection curves of two different surfaces deforming over generalized offset vector fields.  ...  The generic structure of the 3D medial axis is a set of smooth surfaces along with a singular set consisting of edge curves, branch curves, fin points and six junction points.  ...  extraction [26, 28] , tool-path creation in computer-aided manufacturing [25] and shape search and retrieval [43] .  ... 
doi:10.1016/j.cad.2011.08.023 fatcat:yolqbcikmzbybbxjmprfu7a4zu

Geometry and Domain Modelling for Construction Robots [chapter]

R. F. Woodbury, W. T. Keirouz, I. J. Oppenheim, D. R. Rehak
1986 CAD and Robotics in Architecture and Construction  
All of these differences provide arguments for two related capabilities that are required of construction robots: the ability to reason obmur and to murlc•l their environment.  ...  -flex and more dynamic than is the norm in ntanutacuiring.  ...  There exist efficient (and often optimal) algorithms for [lie computation of many of these properties. • Many geometric operations and questions are used very widely in the course of solving a problem.  ... 
doi:10.1007/978-1-4684-7404-6_18 fatcat:2xbrcwf5wbfwfeyptgiuovc72y

CONSTRAINT MODELING FOR CURVES AND SURFACES IN CAGD: A SURVEY

VINCENT CHEUTET, MARC DANIEL, STEFANIE HAHMANN, RAPHAEL LA GRECA, JEAN-CLAUDE LEON, ROBERT MACULET, DAVID MENEGAUX, BASILE SAUVAGE
2007 International journal of shape modeling  
Computer-Aided Geometric Design modelers are now based on powerful mathematical curve and surface models, but there is still a considerable need for efficient tools to handle, analyze and modify these  ...  Designing product shapes using geometric operations on free-form curves and surfaces is still a tedious task.  ...  Léon and B. Sauvage are also contributing in the scope of the European network  ... 
doi:10.1142/s0218654307000993 fatcat:ut24ngjdjrb7tp2isy7f4d5vsu

Thermal modelling of a fractional-slot concentrated-winding Kaman type Axial-Flux Permanent-Magnet machine

Gy. Vainel, D. A. Staton, F. Giulii Capponi, G. De Donato, F. Caricchi
2013 2013 IEEE Energy Conversion Congress and Exposition  
This is achieved through a lumped parameter network and subdivision of machine into cuboidal elements.  ...  This machine is air-cooled and equipped with specific arrangements to enhance heat dissipation. Thermal paths inside the machine are quite complex and require three-dimensional modelling.  ...  Among the particular manufacturing solutions chosen in this design, flat ribbon conductors have been used for the stator concentrated coils , thus achieving a high slot fill factor, i.e. > 0.7.  ... 
doi:10.1109/ecce.2013.6646883 fatcat:3czr6ym7bfbjrnq6wl25ndqria

Active Vibration Suppression of Acrobatic Aircraft Wing by Acceleration Feedback Controller

Ahmed A., Mahmood Wael
2017 International Journal of Computer Applications  
Results show that utilizing the acceleration feedback method for active vibration controlling method can suppress wing vibration and that will pave the way for further application of this controlling method  ...  In the present work, direct acceleration feedback method is utilized to be used as a controlling technique to satisfy wing stability.  ...  Algorithm is achieved using Matlab tool for calculating the different values of variables.  ... 
doi:10.5120/ijca2017912825 fatcat:b647g4w5rnhvnkljklymvdjwcy

State of the art in lighting simulation for building science: a literature review

Carlos E. Ochoa, Myriam B.C. Aries, Jan L.M. Hensen
2012 Journal of Building Performance Simulation, Taylor & Francis  
Existing models apply roughly the same theoretical algorithms and calculation aids, limiting representation of certain physical phenomena.  ...  Works are grouped using the main aspects of a program (input, modelling, and output).  ...  Data entry methods and guidance for input Frequently used methods include: text files, use of command prompt, translators from computer aided drafting (CAD) programs and graphical user interfaces with  ... 
doi:10.1080/19401493.2011.558211 fatcat:vxlav4qwqjespdrcpmhcurbqba

Feature-based design and material blending for free-form heterogeneous object modeling

Kuntal Samanta, Bahattin Koc
2005 Computer-Aided Design  
In this paper, a new feature-based method is proposed to represent and design heterogeneous objects. Material governing features are defined to control material composition inside the objects.  ...  Interrelations between the material governing features and material attributes are established in the design process and retained in the object model.  ...  Fig. 24 . 24 Smooth B-spline curves representing material features for Example part IV. K.Samanta, B. Koc / Computer-Aided Design 37 (2005) 287-305  ... 
doi:10.1016/j.cad.2004.03.005 fatcat:iu2zaxklmvd5pewsn4cqqkejgm

From geometric design to numerical analysis: A direct approach using the Finite Cell Method on Constructive Solid Geometry

Benjamin Wassermann, Stefan Kollmannsberger, Tino Bog, Ernst Rank
2017 Computers and Mathematics with Applications  
During the last ten years, increasing efforts were made to improve and simplify the process from Computer Aided Design (CAD) modeling to a numerical simulation.  ...  Isogeometric Analysis (IGA), which applies the shape functions used for the geometry description (typically B-Splines and NURBS) directly to the numerical analysis.  ...  Acknowledgements The first and the last author gratefully acknowledge the financial support of the German Research Foundation (DFG) under Grant RA 624/22-1.  ... 
doi:10.1016/j.camwa.2017.01.027 fatcat:yv5im47obrbjznjotlxafgkvzu

Towards an Analysis of Daylighting Simulation Software

Ignacio Acosta, Jaime Navarro, Juan J. Sendra
2011 Energies  
The aim of this article was to assess some of the main lighting software programs habitually used in architecture, subjecting them to a series of trials and analyzing the light distribution obtained in  ...  The analysis examines Lightscape 3.2, Desktop Radiance 2.0, Lumen Micro 7.5, Ecotect 5.5 and Dialux 4.4.  ...  The comparison of the daylight factors shows significant differences between the computer calculations and the measurements carried out with the aid of an artificial sky.  ... 
doi:10.3390/en4071010 fatcat:nus63jie6nhrpdmykwcoj7dtk4

Sobre cáscaras y blobs: Superficies estructurales de la era digital

Martin Bechthold
2006 ARQ (Santiago. Impresa)  
On shells and blobs Structural surfaces in the digital age 1 We all know that computer-aided design and manufacturing (CAD/CAM) technology has triggered a proliferation of complexly shaped building designs  ...  The process was then tested on a six-foot long prototype. Bibliography / Bechthold, Martin. Complex shapes in wood: Computer aided design and manufacturing techniques.  ... 
doi:10.4067/s0717-69962006000200007 fatcat:2fotxtvgefcy7krr6whihp6jie

Artificial Neural Networks Based Optimization Techniques: A Review

Maher G. M. Abdolrasol, S. M. Suhail Hussain, Taha Selim Ustun, Mahidur R. Sarker, Mahammad A. Hannan, Ramizi Mohamed, Jamal Abd Ali, Saad Mekhilef, Abdalrhman Milad
2021 Electronics  
The obtained neural net is used for solving energy management problems in the virtual power plant system.  ...  This paper includes some results for improving the ANN performance by PSO, GA, ABC, and BSA optimization techniques, respectively, to search for optimal parameters, e.g., the number of neurons in the hidden  ...  ANN is also used to optimize and control thin film growth processes [85] . A sampling method for the ANN model's optimal design [86] .  ... 
doi:10.3390/electronics10212689 fatcat:oupnikhxdbhedfz5yeatmtj4xa

Performance characteristics of the Spiky Central Receiver Air Pre-heater (SCRAP)

M. Lubkoll, D.J. Erasmus, T.M. Harms, T.W. von Backström, D.G. Kröger
2020 Solar Energy  
The iii Stellenbosch University https://scholar.sun.ac.za iv ABSTRACT developed thermodynamic computer model was verified against an experimental test setup designed and built at the heat transfer laboratory  ...  The development and writing of the papers (published and unpublished) were the principle responsibility of myself and, for each of the cases where this is not the case, a declaration is included in the  ...  crossed-strings-method (a) general illustration for F 1→2 between two surfaces, (b) and (c) for computation of F 1→2 between top and bottom of a rectangular duct and between the bottom and a wall segment  ... 
doi:10.1016/j.solener.2020.03.027 fatcat:25wnqx57k5dhxhhljcvg5a5bpm

3D reconstruction and analysis of wing deformation in free-flying dragonflies

C. Koehler, Z. Liang, Z. Gaston, H. Wan, H. Dong
2012 Journal of Experimental Biology  
The reconstruction method makes no rigid wing assumptions and allows for an arbitrary arrangement of marker points on the interior and edges of each wing.  ...  Using an Eastern pondhawk (Erythimus simplicicollis) dragonfly for demonstration, we quantify and visualize the wing twist and camber in both the chord-wise and span-wise directions, and discuss the implications  ...  Given at least 6 marker point correspondences, the DLT algorithm is used for calibration.  ... 
doi:10.1242/jeb.069005 pmid:22660780 fatcat:jgy24k5c3jhvxfbmhiztghckia

CAD-based computer vision: from CAD models to relational graphs

P.J. Flynn, A.K. Jain
1991 IEEE Transactions on Pattern Analysis and Machine Intelligence  
J-D object recognition is a difficult and yet an important problem in computer vision.  ...  In this paper, we focus on the topic of mode&building for 3-D objects.  ...  ACKNOWLEDGMENT The authors wish to thank the anonymous referees for 1271 very valuable comments, and Dr. P. Besl for providing scanconversion software. PI  ... 
doi:10.1109/34.67642 fatcat:gzvqjviklrcqfknqu2fkerhzgm
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