Transport in 3D volume-preserving flows

1994 ◽  
Vol 4 (1) ◽  
pp. 329-354 ◽  
Author(s):  
R. S. MacKay
Keyword(s):  
2008 ◽  
Vol 7 (4) ◽  
pp. 1527-1557 ◽  
Author(s):  
Héctor E. Lomelí ◽  
Rafael Ramírez-Ros

Nonlinearity ◽  
2018 ◽  
Vol 31 (12) ◽  
pp. 5615-5642 ◽  
Author(s):  
James D Meiss ◽  
Narcís Miguel ◽  
Carles Simó ◽  
Arturo Vieiro

2005 ◽  
Vol 173 (4S) ◽  
pp. 464-464
Author(s):  
Ithaar H. Derweesh ◽  
Gaspar A. Motta-Ramirez ◽  
Mahesh Gael ◽  
Nancy Obuchowski ◽  
Hazem A. Moneim ◽  
...  

2010 ◽  
Vol 63 (2) ◽  
pp. 80-83 ◽  
Author(s):  
Károly Vincze ◽  
Péter Zádori ◽  
Zsolt Magyaródi ◽  
Gyula Horváth

Absztrakt A szerzők a világirodalmi ritkaságnak számító atraumaticus (spontán) mellkasfali tüdősérvet ismertetik. Két operált betegük kapcsán bemutatják a sérv kialakulását elősegítő körülményeket és a kórkép klinikai jellemzőit. Mindkét betegük spontán mellkasfali (intercostalis) sérvét chronicus obstructiv syndroma (COPD) okozta makacs köhögés váltotta ki. Az elvégzett multislice spirál CT (MSCT) vizsgálat, valamint a speciális szoftver segítségével készített másodlagos 3D „volume-rendering” (VRT) rekonstrukciós képek egyértelműen utaltak a ritka kórformára. Az MSCT-vizsgálatok a Kaposi Mór Oktató Kórházban készültek, Siemens Somatom Emotion 6 MSCT-berendezéssel. A pontos diagnózis birtokában végzett mellkasfali korrekciók tartós gyógyuláshoz vezettek. A szerzők röviden ismertetik a mellkasfali sérvekkel kapcsolatos hazai és fontosabb külföldi irodalmi vonatkozásokat. A kórkép rendkívüli ritkasága ellenére a kialakulásában szerepet játszó COPD elterjedtsége miatt érdemel figyelmet. A hasonló esetek diagnosztikájában nagy segítséget jelenthet a bemutatott korszerű képalkotó eljárás alkalmazása.


Micron ◽  
2010 ◽  
Vol 41 (7) ◽  
pp. 886.e1-886.e17 ◽  
Author(s):  
Bernhard Ruthensteiner ◽  
Natalie Baeumler ◽  
David G. Barnes

2011 ◽  
Vol 69 (4) ◽  
pp. 842-858 ◽  
Author(s):  
Yibao Li ◽  
Eunok Jung ◽  
Wanho Lee ◽  
Hyun Geun Lee ◽  
Junseok Kim

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
T. M. Schwarz ◽  
C. A. Dietrich ◽  
J. Ott ◽  
E. M. Weikum ◽  
R. Lawitzki ◽  
...  

AbstractAtom Probe Tomography (APT) is currently a well-established technique to analyse the composition of solid materials including metals, semiconductors and ceramics with up to near-atomic resolution. Using an aqueous glucose solution, we now extended the technique to frozen solutions. While the mass signals of the common glucose fragments CxHy and CxOyHz overlap with (H2O)nH from water, we achieved stoichiometrically correct values via signal deconvolution. Density functional theory (DFT) calculations were performed to investigate the stability of the detected pyranose fragments. This paper demonstrates APT’s capabilities to achieve sub-nanometre resolution in tracing whole glucose molecules in a frozen solution by using cryogenic workflows. We use a solution of defined concentration to investigate the chemical resolution capabilities as a step toward the measurement of biological molecules. Due to the evaporation of nearly intact glucose molecules, their position within the measured 3D volume of the solution can be determined with sub-nanometre resolution. Our analyses take analytical techniques to a new level, since chemical characterization methods for cryogenically-frozen solutions or biological materials are limited.


2021 ◽  
Vol 10 (3) ◽  
pp. 157
Author(s):  
Paul-Mark DiFrancesco ◽  
David A. Bonneau ◽  
D. Jean Hutchinson

Key to the quantification of rockfall hazard is an understanding of its magnitude-frequency behaviour. Remote sensing has allowed for the accurate observation of rockfall activity, with methods being developed for digitally assembling the monitored occurrences into a rockfall database. A prevalent challenge is the quantification of rockfall volume, whilst fully considering the 3D information stored in each of the extracted rockfall point clouds. Surface reconstruction is utilized to construct a 3D digital surface representation, allowing for an estimation of the volume of space that a point cloud occupies. Given various point cloud imperfections, it is difficult for methods to generate digital surface representations of rockfall with detailed geometry and correct topology. In this study, we tested four different computational geometry-based surface reconstruction methods on a database comprised of 3668 rockfalls. The database was derived from a 5-year LiDAR monitoring campaign of an active rock slope in interior British Columbia, Canada. Each method resulted in a different magnitude-frequency distribution of rockfall. The implications of 3D volume estimation were demonstrated utilizing surface mesh visualization, cumulative magnitude-frequency plots, power-law fitting, and projected annual frequencies of rockfall occurrence. The 3D volume estimation methods caused a notable shift in the magnitude-frequency relations, while the power-law scaling parameters remained relatively similar. We determined that the optimal 3D volume calculation approach is a hybrid methodology comprised of the Power Crust reconstruction and the Alpha Solid reconstruction. The Alpha Solid approach is to be used on small-scale point clouds, characterized with high curvatures relative to their sampling density, which challenge the Power Crust sampling assumptions.


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