455,993 Hits in 3.9 sec

Evaluation and correction of laser-scanned point clouds

Christian Teutsch, Tobias Isenberg, Erik Trostmann, Michael Weber, Dirk Berndt, Thomas Strothotte, J.-Angelo Beraldin, Sabry F. El-Hakim, Armin Gruen, James S. Walton
2005 Videometrics VIII  
Furthermore, operations on optimized meshes consider the entire model and pay only little attention to individual measurements.  ...  Measurements on the generated data leads to incorrect results if the contained error is too high.  ...  To ensure that a B-spline curve approximates given points in an optimal way, control points have to be generated from the measured points.  ... 
doi:10.1117/12.585450 fatcat:v4cwncrgjbg7lhu6nbrrpbpyry

Reverse Engineering of 3D Models Based on Image Processing and 3D Scanning Techniques [chapter]

A. Manor, A. Fischer
2001 Geometric Modelling  
A new method based on fusion of 3D scanned data and an intensity image is proposed to overcome the above problems and improve the accuracy of the reconstructed surface.  ...  3D laser scanners play an essential role in Reverse Engineering. Laser-based sensors are non-contact fast sensors and therefore are commonly used to digitize the object.  ...  points have been parameterized and the 3D boundary of the object has been determined, we can proceed to fit a surface interpolating the boundary and approximating the inner measured data points.  ... 
doi:10.1007/978-0-387-35490-3_23 fatcat:warkkslicrcrhjlnwwdg4mpt3u

Optimization-Based Inverse Identification of the Parameters of a Concrete Cap Material Model

Petr Král, Filip Hokeš, Martin Hušek, Jiří Kala, Petr Hradil
2017 IOP Conference Series: Materials Science and Engineering  
will best approximate the experimental data.  ...  Parameter identification goes hand in hand with experimental investigation while it trying to find parameter values of the used material model so that the resulting data obtained from the computer simulation  ...  Acknowledgments This outcome has been achieved with the financial support of the project GACR 17-23578S "Damage assessment identification for reinforced concrete subjected to extreme loading" provided  ... 
doi:10.1088/1757-899x/245/3/032078 fatcat:fzvxkwmauvhhhk6n3bnpsi6ksu

Surface Fitting for Quasi Scattered Data from Coordinate Measuring Systems

Qing Mao, Shugui Liu, Sen Wang, Xinhui Ma
2018 Sensors  
In [28,31] scattered data points are projected to base surfaces to do parameterization according to parameters of the projected points.  ...  Surface approximation to scanned data. Vis. Comput. 2000, 16, 386–395. [CrossRef] 19. Pan, R.; Skala, V. Continuous global optimization in surface reconstruction from an oriented point cloud.  ... 
doi:10.3390/s18010214 pmid:29342869 pmcid:PMC5796382 fatcat:pp7loxfuvffobhz6vu3caa3dia

A Gaussian Filter for Plate Flatness Evaluation System with 3-D Scanner

Shinichiro Aoe, Masaru Miyake, Kazuhisa Kabeya
2017 ISIJ International  
This approximation greatly reduced the calculation time needed to estimate the optimal smoothing.  ...  The engine generated clear surfaces and was robust against various dirty point clouds.  ...  It took 9.8 sec to calculate the plate surface in Fig. 6 and 226 sec to calculate the optimal smoothing parameter.  ... 
doi:10.2355/isijinternational.isijint-2016-559 fatcat:msvqr2yl7je5rdwkhs5hn6av2e

Inverse identification of the material parameters of a nonlinear concrete constitutive model based on the triaxial compression strength testing

Petr Král, Petr Hradil, Jií Kala
2016 Frattura ed Integrità Strutturale  
When applying such parameters, the resulting response of the structure obtained from a computer simulation is very similar to the real response of the structure based on the related experimental measurement  ...  For the purposes of the inverse analysis performed in this paper the experimental data was obtained from the triaxial compression strength tests carried out on the concrete cylinders.  ...  Financial assistance was also received via project FAST-J-16-3744 "Optimization of the parameters of nonlinear concrete material models for explicit dynamics"; this instrument was structured and guaranteed  ... 
doi:10.3221/igf-esis.39.05 fatcat:f4nmvwbenre3jjj4yzkc4gyoam

Fitting curves and surfaces to point clouds in the presence of obstacles

Simon Flöry
2009 Computer Aided Geometric Design  
We consider the problem of fitting B-spline curves and surfaces to point clouds in the presence of obstacles constraining this approximation at the same time.  ...  We discuss several numerical aspects of this constrained optimization and present experimental results for B-spline curve and surface fittings in the presence of obstacles.  ...  Acknowledgements I would like to thank Helmut Pottmann for his valuable comments and suggestions throughout the development of this work and the anonymous reviewer for their efforts to improve the paper  ... 
doi:10.1016/j.cagd.2008.04.003 fatcat:4iritpxk7fhftbl3qxvzgwqjgm

Constrained curve fitting on manifolds

Simon Flöry, Michael Hofer
2008 Computer-Aided Design  
When designing curves on surfaces the need arises to approximate a given noisy target shape by a smooth fitting shape.  ...  We discuss the problem of fitting a B-spline curve to a point cloud by squared distance minimization in the case that both, the point cloud and the fitting curve, are constrained to lie on a smooth manifold  ...  Acknowledgements We would like to thank the Austrian Science Fund (FWF) for supporting our work under grants P16002 and P18865.  ... 
doi:10.1016/j.cad.2007.01.012 fatcat:kdm3n2o6gnfkpices5eevdad5i

Fitness function and nonunique solutions in x-ray reflectivity curve fitting: crosserror between surface roughness and mass density

J Tiilikainen, V Bosund, M Mattila, T Hakkarainen, J Sormunen, H Lipsanen
2007 Journal of Physics D: Applied Physics  
) curve fitting problem were studied by modelling layer structures with neural networks and designing a fitness function to handle the nonidealities of measurements.  ...  Lipsanen, Fitness function and nonunique solutions in x-ray reflectivity curve fitting: Crosserror between surface roughness and mass density, Abstract Nonunique solutions of the x-ray reflectivity (XRR  ...  Acknowledgments The authors acknowledge the Finnish Agency for Technology and Innovation (TEKES, ALDUS Project) and the Academy of Finland for supporting this work financially.  ... 
doi:10.1088/0022-3727/40/14/023 fatcat:it4isf5p4jbplchp3rjo375myy

Discussion on Reverse Design of Components with Complex Curved Surface and Computer Numerical Control Machining

Dapeng Fu, Xinyu Lv, Shuangyang Jiang
2018 Journal of Electronic Research and Application  
Among them, curved surface generation and data processing are the focus of management and design, which necessitate the full application of reverse design of complex curved surface components to complete  ...  numerical control processing, effective optimization and upgrading, integration the tasks of point cloud data collection and point cloud data processing to ensure that the corresponding computer numerical  ...  Based on the guaranteed tolerance, the milling process parameters were set and optimized, and the straight line fitting approximation curve method was used to conduct comprehensive process, which can improve  ... 
doi:10.26689/jera.v2i4.508 fatcat:ki3lw2clbbetpkss23riofdfu4

TLS-Based Feature Extraction and 3D Modeling for Arch Structures

Xiangyang Xu, Xin Zhao, Hao Yang, Ingo Neumann
2017 Journal of Sensors  
The paper discusses the accuracy of fittings in four cases between whole curve, segmentation, polynomial, and B-spline.  ...  The ideal modeling strategy should be fast, accurate, and less complex regarding its application to large amounts of data.  ...  Ordinary Bspline approximation involves data parameterization, knot adjustment, and control point determination.  ... 
doi:10.1155/2017/9124254 fatcat:ue6n5tjb7ngznf246kfwqylqqi

Prediction of Bolted Joint Dynamics Based on the Thin-Layer Element of Nonlinear Material

Delin Sun, Lingling Zhao, Guihang Liang, Huawei Zhou
2019 Annales de Chimie - Science des Materiaux  
On this basis, the response surface methodology (RSM) and the genetic algorithm (GA) were combined to identify the parameters of the material in the finite-element model.  ...  The simulated force-displacement curve agrees well with that measured through experiment.  ...  Parameter identification based on Abaqus and Isight As shown in Figure 5 , Abaqus and Isight were combined to establish the response surface function and optimize model parameters.  ... 
doi:10.18280/acsm.430506 fatcat:74nvhrfwj5dwrmxqsubhj3aagm

Capturing planar shapes by approximating their outlines

M. Sarfraz, M. Riyazuddin, M.H. Baig
2006 Journal of Computational and Applied Mathematics  
In addition to independent studies of the optimization of weight and knot parameters of the NURBS, a separate scheme has also been developed for the optimization of weights and knots simultaneously.  ...  The optimized NURBS models have been fitted over the contour data of the planar shapes for the ultimate and automatic output.  ...  Acknowledgements The authors are thankful to the anonymous referees for their helpful and valuable suggestions towards the improvement of this manuscript.  ... 
doi:10.1016/ fatcat:k32yld5v6vf55p2dm4xjv6uil4

Firefly Algorithm for Polynomial Bézier Surface Parameterization

Akemi Gálvez, Andrés Iglesias
2013 Journal of Applied Mathematics  
A classical issue in many applied fields is to obtain an approximating surface to a given set of data points.  ...  In real-world settings, data points are generally irregularly sampled and subjected to measurement noise, leading to a very difficult nonlinear continuous optimization problem, unsolvable with standard  ...  Special thanks are due to the Editor and the anonymous reviewers for their useful comments and suggestions that allowed us to improve the final version of this paper.  ... 
doi:10.1155/2013/237984 fatcat:qwmbsreanzbwne4uspeq2rskzi

A parameter estimation technique for stochastic self-assembly systems and its application to human papillomavirus self-assembly

M Senthil Kumar, Russell Schwartz
2010 Physical Biology  
Our method combines quadratic response surface and quasi-gradient-descent approximations to deal with the high computational cost of simulations, stochastic noise in simulation trajectories, and limitations  ...  and are in good concordance with prior analysis of the data.  ...  We are grateful to David Wu for providing the HPV light scattering data used in the present work.  ... 
doi:10.1088/1478-3975/7/4/045005 pmid:21149973 pmcid:PMC3128809 fatcat:r5cn7hu55zbw3j3winq3jsfshu
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