2,467 research outputs found
Simple and Robust Boolean Operations for Triangulated Surfaces
Boolean operations of geometric models is an essential issue in computational
geometry. In this paper, we develop a simple and robust approach to perform
Boolean operations on closed and open triangulated surfaces. Our method mainly
has two stages: (1) We firstly find out candidate intersected-triangles pairs
based on Octree and then compute the inter-section lines for all pairs of
triangles with parallel algorithm; (2) We form closed or open
intersection-loops, sub-surfaces and sub-blocks quite robustly only according
to the cleared and updated topology of meshes while without coordinate
computations for geometric enti-ties. A novel technique instead of
inside/outside classification is also proposed to distinguish the resulting
union, subtraction and intersection. Several examples have been given to
illus-trate the effectiveness of our approach.Comment: Novel method for determining Union, Subtraction and Intersectio
Modular matrices from universal wave function overlaps in Gutzwiller-projected parton wave functions
We implement the universal wave function overlap (UWFO) method to extract
modular and matrices for topological orders in Gutzwiller-projected
parton wave functions (GPWFs). The modular and matrices generate a
projective representation of on the degenerate-ground-state
Hilbert space on a torus and may fully characterize the 2+1D topological
orders, i.e. the quasi-particle statistics and chiral central charge (up to
bosonic quantum Hall states). We used the variational Monte Carlo method
to computed the and matrices of the chiral spin liquid (CSL)
constructed by the GPWF on the square lattice, and confirm that the CSL carries
the same topological order as the bosonic Laughlin state. We
find that the non-universal exponents in UWFO can be small and direct numerical
computation is able to be applied on relatively large systems. We also discuss
the UWFO method for GPWFs on other Bravais lattices in two and three dimensions
by using the Monte Carlo method. UWFO may be a powerful method to calculate the
topological order in GPWFs.Comment: 5 pages with 3 figure
Thermodynamics of the Schwarzschild-AdS black hole with a minimal length
Using the mass-smeared scheme of black holes, we study the thermodynamics of
black holes. Two interesting models are considered. One is the self-regular
Schwarzschild-AdS black hole whose mass density is given by the analogue to
probability densities of quantum hydrogen atoms. The other model is the same
black hole but whose mass density is chosen to be a rational fractional
function of radial coordinates. Both mass densities are in fact analytic
expressions of the -function. We analyze the phase structures of the
two models by investigating the heat capacity at constant pressure and the
Gibbs free energy in an isothermal-isobaric ensemble. Both models fail to decay
into the pure thermal radiation even with the positive Gibbs free energy due to
the existence of a minimal length. Furthermore, we extend our analysis to a
general mass-smeared form that is also associated with the -function,
and indicate the similar thermodynamic properties for various possible
mass-smeared forms based on the -function.Comment: v1: 25 pages, 14 figures; v2: 26 pages, 15 figures; v3: minor
revisions, final version to appear in Adv. High Energy Phy
Discrete Surface Modeling Based on Google Earth: A Case Study
Google Earth (GE) has become a powerful tool for geological, geophysical and
geographical modeling; yet GE can be accepted to acquire elevation data of
terrain. In this paper, we present a real study case of building the discrete
surface model (DSM) at Haut-Barr Castle in France based on the elevation data
of terrain points extracted from GE using the COM API. We first locate the
position of Haut-Barr Castle and determine the region of the study area, then
extract elevation data of terrain at Haut-Barr, and thirdly create a planar
triangular mesh that covers the study area and finally generate the desired DSM
by calculating the elevation of vertices in the planar mesh via interpolating
with Universal Kriging (UK) and Inverse Distance Weighting (IDW). The generated
DSM can reflect the features of the ground surface at Haut-Barr well, and can
be used for constructingthe Sealed Engineering Geological Model (SEGM) in
further step.Comment: Proceedings of IEEE Conference, ICCSNT 2012, in Pres
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