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CURDIS:A template for incremental curve discretization algorithms and its application to conics

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虚拟现实与智能硬件（中英文） 2024年第5期6卷 358-382页

作者： Philippe LATOUR Marc van droogenbroeck Montefiore Institute University of LiègeQuartier Polytech 1Allée de la découverte 104000 LiègeBelgium

We introduce CURDIS,a template for algorithms to discretize arcs of regular curves by incrementally producing a list of support pixels covering the *** this template,algorithms proceed by finding the tangent quadrant at each point of the arc and determining which side the curve exits the pixel according to a tailored *** two elements can be adapted for any type of curve,leading to algorithms dedicated to the shape of specific *** the calculation of the tangent quadrant for various curves,such as lines,conics,or cubics,is simple,it is more complex to analyze how pixels are traversed by the *** the case of conic arcs,we found a criterion for determining the pixel exit *** leads us to present a new algorithm,called CURDIS-C,specific to the discretization of conics,for which we provide all the ***,the criterion for conics requires between one and three sign tests and four additions per pixel,making the algorithm efficient for resource-constrained systems and feasible for fixed-point or integer arithmetic *** algorithm also perfectly handles the pathological cases in which the conic intersects a pixel twice or changes quadrants multiple times within this pixel,achieving this generality at the cost of potentially computing up to two square roots per *** illustrate the use of CURDIS for the discretization of different curves,such as ellipses,hyperbolas,and parabolas,even when they degenerate into lines or corners.

关键词： Computer graphics Curve discretization Conics Rasterization Ellipse drawing Conic spline Conic pencil

Numerical modeling techniques for noise emission of free railway wheels

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Railway Engineering Science 2024年第2期32卷 144-161页

作者： Linus Taenzer Urs Pachale bart van Damme Andrea Bergamini Domenico Tallarico Laboratory of Acoustics/Noise Control EmpaÜberlandstrasse 129DübendorfSwitzerland

In this article,we consider the numerical prediction of the noise emission from a wheelset in laboratory *** focus on the fluid-structure interaction leading to sound emission in the fluid domain by analyzing three different methods to account for acoustic *** are a discretized baffled piston using the discrete calculation method(DCM),a closed cylindrical volume using the boundary element method(BEM)and radiating elastic disks in a cubic enclosure solved with the finite element method(FEM).We provide the validation of the baffled piston and the BEM using measurements of the noise emission of a railway wheel by considering ground reflections in the numerical *** space-resolved waveforms are compared with experimental results as well as with a fluid-structure interaction finite element *** computational advantage of a discretized disk mounted on a baffle and BEM compared to FEM is highlighted,and the baffled pistons limitations caused by a lack of edge radiation effects are investigated.

关键词： Discretized baffled piston Finite element Boundary element Railway noise Acoustic emission Vibrations

Surface modification of HKUST-1 for enhanced activity of immobilized formate dehydrogenase used in CO_(2)hydrogenation

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Carbon Resources Conversion 2024年第1期7卷 89-102,F0004页

作者： Shadeera Rouf Yaser E.Greish bart van der Bruggen Sulaiman Al-Zuhair Department of Chemical and Petroleum Engineering UAE University15551 Al AinUnited Arab Emirates Department of Chemistry UAE University15551 Al AinUnited Arab Emirates Department of Chemical Engineering KU Leuven3000 LeuvenBelgium

Post synthetic modification of a hydrophilic metal-organic framework(MOF),HKUST-1,with stearic acid(SA)was carried out to enhance the stability of HKUST-1 in aqueous solution to be used as a support for formate dehydrogenase(FDH)used for CO_(2)conversion to *** modification improved the hydrophobicity without affecting the morphology and crystal structure of *** of FDH on the modified MOF(SA@HKUST-1)was compared to that of the native HKUST-1 and *** adsorption kinetics on all MOFs was found to follow pseudo-second order kinetics and the isotherm was best described by Freundlich *** high stability of SA@HKUST-1 and enhanced hydrophobic interaction between support and CO_(2)resulted in high catalytic efficiency and stability of FDH@SA@*** immobilized enzyme retained 95.1%of its initial activity after 4 cycles of repeated *** was also shown that FDH@SA@HKUST-1 retained morphology and crystal structure after repeated *** of the present work provide novel insight into the influence of hydrophobic MOFs on the activity and stability of immobilized *** findings are expected to assist in developing highly active and stable biocatalysts for CO_(2)hydrogenation at commercial level.

关键词： CO_(2)hydrogenation Formate dehydrogenase Metal organic frameworks Hydrophobic MOFs Formate

Tree species identity and interaction determine vertical forest structure in young planted forests measured by terrestrial laser scanning

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Forest Ecosystems 2024年第3期11卷 266-275页

作者： Mengxi Wang Lander Baeten Frieke van Coillie Kim Calders Kris Verheyen Quentin Ponette Haben Blondeel bart Muys John Armston Hans Verbeeck Q-ForestLab Department of EnvironmentFaculty of Bioscience EngineeringGhent UniversityBelgium Forest&Nature Lab Department of EnvironmentFaculty of Bioscience EngineeringGhent UniversityBelgium Earth and Life Institute Université Catholique de Louvain(UCLouvain)Louvain-la-NeuveBelgium Department of Earth&Environmental Sciences KU LeuvenBelgium Department of Geographical Sciences University of MarylandCollege ParkMDUSA

Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and *** tree species in planted forests has the potential to create diverse vertical forest structures due to the different physiological and morphological traits of the composing tree ***,the relative importance of species richness,species identity and species interactions for the variation in vertical forest structure remains unclear,mainly because traditional forest inventories do not observe vertical stand structure in *** laser scanning(TLS),however,allows to study vertical forest structure in an unprecedented ***,we used TLS single scan data from 126 plots across three experimental planted forests of a largescale tree diversity experiment in Belgium to study the drivers of vertical forest *** plots were 9–11years old young pure and mixed forests,characterized by four levels of tree species richness ranging from monocultures to four-species mixtures,across twenty composition *** generated vertical plant profiles from the TLS data and derived six stand structural *** mixed models were used to test the effect of species richness on structural *** a hierarchical diversity interaction modelling framework,we further assessed species identity effect and various species interaction effects on the six stand structural *** results showed that species richness did not significantly influence most of the stand structure variables,except for canopy height and foliage height *** identity on the other hand exhibited a significant impact on vertical forest structure across all *** interaction effects were observed to be site-dependent due to varying site conditions and species pools,and rapidly growing tree species tend to dominate these ***,our results highlighted the importance of considering both species identity an

关键词： TreeDivNet FORBIO Stand structural complexity Terrestrial laser scanning Vertical forest structure Tree diversity Planted forests

Intraoperative application of three-dimensional printed guides in total hip arthroplasty: A systematic review

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World Journal of Orthopedics 2024年第7期15卷 660-667页

作者： Tim P Crone bart M W Cornelissen Jakob van Oldenrijk Pieter Koen Bos Ewout S Veltman Department of Orthopedic Surgery and Sports Medicine Erasmus Medical CenterRotterdam 3015 GDNetherlands Department of Oral and Maxillofacial Surgery Erasmus Medical CenterRotterdam 3015 GDNetherlands

BACKGROUND Acetabular component positioning in total hip arthroplasty(THA)is of key importance to ensure satisfactory post-operative outcomes and to minimize the risk of *** majority of acetabular components are aligned freehand,without the use of navigation *** specific instruments(PSI)and three-dimensional(3D)printing of THA placement guides are increasingly used in primary THA to ensure optimal *** To summarize the literature on 3D printing in THA and how they improve acetabular component *** PubMed was used to identify and access scientific studies reporting on different 3D printing methods used in *** studies with 236 hips in 228 patients were *** studies could be divided into two main categories;3D printed models and 3D printed *** 3D printing in THA helped improve preoperative cup size planning and post-operative Harris hip scores between intervention and control groups(P=0.019,P=0.009).Otherwise,outcome measures were heterogeneous and thus difficult to *** overarching consensus between the studies is that the use of 3D guidance tools can assist in improving THA cup positioning and reduce the need for revision THA and the associated *** The implementation of 3D printing and PSI for primary THA can significantly improve the positioning accuracy of the acetabular cup component and reduce the number of complications caused by malpositioning.

关键词： Total hip arthroplasty Three-dimensional printing Hip replacement surgery Three-dimensional planning Surgical guides

Supramolecular Polymerization of Hydrogen-Bonded Trimers in Bulk and Aqueous Medium

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CCS Chemistry 2024年第6期6卷 1458-1465页

作者： Freek V.de Graaf Stef A.H.Jansen Sandra M.C.Schoenmakers Bas van Genabeek Marle E.J.Vleugels bart W.L.van den Bersselaar E.W.Meijer Ghislaine vantomme Institute for Complex Molecular Systems Laboratory of Macromolecular and Organic ChemistryEindhoven University of Technology5600 MBEindhoven School of Chemistry and RNA Institute University of New South WalesSydneyNew South Wales 2052

Synthetic molecules that form functional noncovalent assemblies in water have received much attention for their potential applications as *** this work,we introduce a novel water-compatible monomer based on the phthalhydrazide moiety that assembles into hydrogen-bonded trimeric *** bulk,the material exhibits a cylindrical nanostructure in the liquid-crystalline phase at elevated temperatures,morphologically distinct from the crystalline lamellar *** water,these molecules effectively form cylinders in a one-dimensional fashion,yielding fibrous *** formation of these supramolecular polymers follows a cooperative mechanism,as evidenced by denaturation *** trimerized pattern represents a new category of aqueous su pramolecular polymers with future prospects for functional complex molecular systems.

关键词： noncovalent chemistry supramolecular polymers hydrogen bonding cooperativity nanostructure

Single-emitter super-resolved imaging of radiative decay rate enhancement in dielectric gap nanoantennas

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Light(Science & Applications) 2024年第1期13卷 47-54页

作者： R.Margoth Córdova-Castro bart van Dam Alberto Lauri Stefan A.Maier Riccardo Sapienza Yannick De Wilde Ignacio Izeddin Valentina Krachmalnicoff Institut Langevin ESPCI ParisPSL UniversityCNRSParisFrance The Blackett Laboratory Department of PhysicsImperial College LondonLondonUK School of Physics and Astronomy Monash UniversityClaytonVictoriaAustralia Chair in Hybrid Nanosystems Ludwig-Maximilians Universität MünchenMuenchenGermany Department of Physics University of OttawaOttawaONCanada

High refractive index dielectric nanoantennas strongly modify the decay rate via the Purcell effect through the design of radiative *** to their dielectric nature,the field is mainly confined inside the nanostructure and in the gap,which is hard to probe with scanning probe *** we use single-molecule fluorescence lifetime imaging microscopy(smFLIM)to map the decay rate enhancement in dielectric GaP nanoantenna dimers with a median localization precision of 14 *** measure,in the gap of the nanoantenna,decay rates that are almost 30 times larger than on a glass *** comparing experimental results with numerical simulations we show that this large enhancement is essentially radiative,contrary to the case of plasmonic nanoantennas,and therefore has great potential for applications such as quantum optics and biosensing.

关键词： dielectric decay radiative

Flapping vortex dynamics of two coupled side-by-side flexible plates submerged in the wake of a square cylinder

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International Journal of Fluid Engineering

International Journal of Fluid Engineering 2024年第1期 40-55页

作者： Bin Xu Hao Wang Weibin Zhang Yilin Deng Xi Shen Desheng Zhang B.P.M.(bart) van Esch Research Center of Fluid Machinery Engineering and Technology Jiangsu University Key Laboratory of Fluid and Power Machinery(Xihua University) Ministry of Education Institute for Energy Research Jiangsu University Eindhoven University of Technology

The flapping vortex dynamics of two flexible plates submerged side-by-side in the wake of a square cylinder are investigated through a two-way fluid–structure interaction(FSI) simulation. The gap between the two plates can stabilize wakes, lengthen vortex formation,elongate vortices, suppress vortex shedding, and decrease hydrodynamic forces. The numerical results indicate that the two flexible plates can exhibit four distinct modes of coupled motion: out-of-phase flapping, in-phase flapping, transition flapping, and decoupled flapping,depending on the gap spacing. Additionally, it is discovered that each of the four coupling modes has a unique pattern of vortex development. The findings of this study should proved valuable in the design of FSI-based piezoelectric energy harvesters utilizing cylinder–plate systems.

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On Some Families of Smooth Affine Spherical Varieties of Full Rank

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Acta Mathematica Sinica,English Series 2018年第3期34卷 563-596页

作者： Kay PAULUS Guido PEZZINI bart van STEIRTEGHEM Department Mathematik FA U Erlangen-Niirnberg 91058 Erlangen Germany Dipartimento di Matematica 'Sapienza' Universith di Roma 00185 Roma Italy Department Mathematik FA U Erlangen-Niirnberg & Department of MathematicsMedgar Evers College-City University of New York Brooklyn New York 11225 USA

Let G be a complex connected reductive group. Losev has shown that a smooth affine spherical G-variety X is uniquely determined by its weight monoid, which is the set of irreducible representations of G that occur in the coordinate ring of X. In this paper we use a combinatorial characterization of the weight monoids of smooth affine spherical varieties to classify：（a） all such varieties for G = SL（2） × C~×and（b） all such varieties for G simple which have a G-saturated weight monoid of full rank. We also use the characterization and Knop＇s classification theorem for multiplicity free Hamiltonian manifolds to give a new proof of Woodward＇s result that every reflective Delzant polytope is the moment polytope of such a manifold.

关键词： Affine spherical variety weight monoid multiplicity free Hamiltonian manifold moment polytope