搜索结果: 1-15 共查到“知识库 几何学基础”相关记录54条 . 查询时间(4.556 秒)
The Ptolemy coordinates for boundary-unipotent SL(n; C)-representations of a
3-manifold group were introduced in [7] inspired by the A-coordinates on higher Teichmuller
space due to Fock and Goncha...
Reduction of Markov chains with two-time-scale state transitions
Reduction Markov chain time scale approximation limit behavior
2014/12/5
We consider a general class of two-time-scale Markov chains whose transition rate matrices
depend on a parameterI. We assume that some transition rates of the Markov chain will tend to
infinity as I...
On the Complexity of 2D Discrete Fixed Point Problem
Complexity 2D Discrete Fixed Point Problem
2012/12/3
While the 3-dimensional analogue of Sperner’s problem in the plane was known to be complete in class PPAD, the complexity of 2D-SPERNER itself is not known to be PPAD-complete or not. In this paper, w...
保持几何结构的一个改进的NMF 算法
非负矩阵分解 几何结构 分离性 聚类
2012/9/10
非负矩阵分解（NMF）是一种基于局部的数据挖掘方法。算法的非负约束使其很适合处理图像等非负数据。然而，原始的NMF 算法和多数改进的NMF 算法并未明确考虑数据的几何结构。本文提出一种改进的非负矩阵分解算法，在矩阵分解过程中明确考虑了数据集的几何信息，包括类内数据和类间数据的关系。在COIL20 和ALOI 数据库上的测试结果表明了算法的有效性。
Expander Graph Based Overlapped Chunked Codes
Expander Graph Based Overlapped Chunked Codes
2012/12/4
Chunked codes are a variation of random linear network codes with low computational complexities. In chunked codes, the packets in a file are grouped into small (non-overlapped or overlapped) chunks, ...
Finding the Maximum Area Parallelogram in a Convex Polygon
Maximum Area Parallelogram Convex Polygon
2012/12/3
We consider the problem of finding the maximum area parallelogram (MAP) inside a given convex polygon. Our main result is an algorithm for computing the MAP
in an n-sided polygon in O(n2) time. Achie...
This paper develops a structural credit risk model to characterize the difference between the economic and recorded default times for a firm.
A quantitative isoperimetric inequality for fractional perimeters
quantitative isoperimetric inequality fractional perimeters
2011/1/14
Recently Frank & Seiringer have shown an isoperimetric inequality for nonlocal perimeter functionals arising from Sobolev seminorms of fractional order. This isoperimetric inequality is improved here ...
Diagonalization-free implementation of spin relaxation theory for large spin systems
NMR EPR relaxation simulation spin dynamics
2011/3/1
The Liouville space spin relaxation theory equations are reformulated in such a way as to avoid the computationally expensive Hamiltonian diagonalization step, replacing it by numerical evaluation of ...
Almost Series-Parallel graphs: structure and colorability
Series-Parallel graphs structure colorability
2011/2/28
The series-parallel (SP) graphs are those containing no topological K4 and are considered trivial.We relax the prohibition distinguishing the SP graphs by forbidding only embeddings of K4 whose edges ...
Rectangular Mixed Elements for Elasticity with Weakly Imposed symmetry Condition
Rectangular Mixed Elements Elasticity symmetry Condition
2011/1/19
We present new rectangular mixed nite elements for linear elasticity.The approach is based on a modi cation of the Hellinger-Reissner functional in which the symmetry of the stress eld is enforced w...
Contracting planar graphs to contractions of triangulations
planar graph dual graph contraction topological minor
2011/1/20
For every graph H, there exists a polynomial-time algorithm deciding if a planar input graph G can be contracted to H. However, the degree of the polynomial depends on the size of H. In this paper, we...
Two remarks on rectangular mixed finite elements for elasticity
Two remarks rectangular finite elements elasticity
2011/1/19
The lowest order nonconforming rectangular element in three dimen-sions involves 54 degrees of freedom for the stress and 12 degrees of freedom for the displacement.
Harmonic deformation of Delaunay triangulations
Harness process Point processes Harmonic functions on graphs Corrector
2011/1/19
We construct harmonic functions on random graphs given by Delaunay triangulations of ergodic
point processes as the limit of the zero-temperature harness process.
Group-Theoretical Classification of BPS and Possibly Protected States in D=4 Conformal Supersymmetry
Group-Theoretical Classification of BPS Possibly Protected States D=4 Conformal Supersymmetry
2011/3/3
We use earlier results on the classification of the positive energy unitary irreducible representations of the N-extended D=4 conformal superalgebras su(2,2/N). These results are applied to the reduct...