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1.
In this article, motivated by a work of Caffarelli and Cordoba in phase transitions analysis, we prove new weighted anisotropic Sobolev type inequalities where different derivatives have different weight functions. These inequalities are also intimately connected to weighted Sobolev inequalities for Grushin type operators, the weights being not necessarily Muckenhoupt. For example we consider Sobolev inequalities on finite cylinders, the weight being a power of the distance function from the top or the bottom of the cylinder. We also prove similar inequalities in the more general case in which the weight is a power of the distance function from a higher codimension part of the boundary.  相似文献   

2.
一类4次旋转对称布尔函数的汉明重量和非线性度   总被引:1,自引:0,他引:1  
旋转对称布尔函数在密码学中具有重要的应用价值.本文研究了一类特殊4次的旋转对称布尔函数的快速求值及其汉明重量的递归关系,通过将该函数分解成数个子函数,并利用这些函数的傅里叶变换值的递归关系,证明了其汉明重量与非线性度相等.本文的结果和处理指数和的方法对于进一步研究Cusick的一个猜想可能有帮助.  相似文献   

3.
假设A是一个Young函数,MD#为广义sharp极大函数.本文首先引进了LA-Hrmander条件,对于满足LA-Hrmander条件的算子T,得到了与T相关的广义sharp极大函数的估计.然后,再利用该估计得到了算子T的加权Lp范数被Hardy-Littlewood极大函数和与Aˉ相关的极大函数的加权Lp范数所控制(0相似文献   

4.
In this paper, we define a new combinatorial function on the edges of complete weighted graphs. This function assigns to each edge of the graph the sum of the weights of all Hamiltonian cycles that contain the edge. Since this function involves the factorial function, whose exact calculation is intractable due to its superexponential asymptotic rate of increase, we also introduce a normalized version of the function that is efficiently computable. From this version, we derive an upper bound to the weight of the minimum weight Hamiltonian cycle of the graph based on the weights of the graph edges. Then we investigate the possible algorithmic applications of this normalized function using the Nearest Neighbor Heuristic and a smallest edge first heuristic. As evidence for its applicability, we show that the use of this function as a criterion for the selection of the next edge, improves the performance of both heuristics for approximating the minimum weight Hamiltonian cycles in Euclidean plane graphs. Moreover, our experimental results show that the use of the function is more suitable with the structure of the smallest edge first heuristic since it provides a solution closer to the best known solution of known hard TSP instances but in \(O(n^3)\) time.  相似文献   

5.
For the special type of weight functions on circular arc we study the asymptotic behavior of the Christoffel kernel off the arc and of the Christoffel function inside the arc. We prove Totik's conjecture for the Christoffel function corresponding to such weight functions.  相似文献   

6.
杨秋霞  王万义 《应用数学》2012,25(1):150-159
研究一类带不定权函数的奇型Sturm-Liouville算子,给出相应自伴算子在无穷点邻域的局部可定性.  相似文献   

7.
The spectral theory for general non–selfadjoint elliptic boundary problems involving a discontinuous weight function has been well developed under certain restrictions concerning the weight function. In the course of extending the results so far established to a more general weight function, there arises the problem of establishing, in an Lp Sobolev space setting, the existence of and a priori estimates for solutions for a boundary problem for the half–space ?n+ involving a weight function which vanishes at the boundary xn = 0. In this paper we resolve this problem.  相似文献   

8.
We consider the Laplacian matrix of a weighted graph, and how the algebraic connectivity, α, behaves when considered as a function of a single edge weight. Under suitable differentiability conditions, we bound the first derivative of α from above, show that α is necessarily concave down, and produce a lower bound on the second derivative of α. When α is simple, we discuss the effect of increasing an edge weight on the corresponding Fiedler vector. We also compute the limiting value of α as the edge weight increases to infinity.  相似文献   

9.
This paper analyzes polynomials orthogonal with respect to the Sobolev inner product with and (x)is a weight function.We study this family of orthogonal polynomials, as linked to the polynomials orthogonal with respect to (x) and we find the recurrence relation verified by such a family. If the weight is semiclassical we obtain a second order differential equation for these polynomials. Finally, an illustrative example is shown.  相似文献   

10.
关于Hardy-Hilbert不等式的单参数推广   总被引:1,自引:1,他引:0  
引入单参数λ及β函数,应用权系数的方法,推广H ardy-H ilbert不等式,并证明常数因子是最佳值.作为应用,建立其等价形式及对应的积分不等式.  相似文献   

11.

Orthogonal polynomials with respect to a weight function defined on a wedge in the plane are studied. A basis of orthogonal polynomials is explicitly constructed for two large class of weight functions and the convergence of Fourier orthogonal expansions is studied. These are used to establish analogous results for orthogonal polynomials on the boundary of the square. As an application, we study the statistics of the associated determinantal point process and use the basis to calculate Stieltjes transforms.

  相似文献   

12.
The paper deals with machine scheduling problems with a general learning effect. By the general learning effect, we mean that the actual processing time of a job is not only a non-increasing function of the total weighted normal processing times of the jobs already processed, but also a non-increasing function of the job’s position in the sequence, where the weight is a position-dependent weight. We show that even with the introduction of a general learning effect to job processing times, some single machine scheduling problems are still polynomially solvable under the proposed model. We also show that some special cases of the flow shop scheduling problems can be solved in polynomial time.  相似文献   

13.
Online Gradient Methods with a Punishing Term for Neural Networks   总被引:1,自引:0,他引:1  
1 IntroductionOnline gradient methods (OGM, for short) are widely used for training neuraJ networks (cf.Il,2,3,4]). Its iterative convergence for linear models is proved in e.g. I5,6,71. A nonlinearn1odel is considered in [8]. During the iterative training procedure, sometimes (see the nextsection of this paper)the weight of the network may become very laxge, causing difficultiesin the implementation of the network by electronic circuits. A revised error fUnction ispresented in [gl to prev…  相似文献   

14.
In this paper we ascertain the exact blow-up rate of the large solutions of a class of sublinear elliptic problems of a logistic type related to the porous media equation, from which we can obtain the uniqueness of the solution. The weight function in front of the nonlinearity vanishes on the boundary of the underlying domain with a general decay rate which can be approximated by a distance function.  相似文献   

15.
In this paper we review techniques for estimating the intensity function of a spatial point process. We present a unified framework of mass preserving general weight function estimators that encompasses both kernel and tessellation based estimators. We give explicit expressions for the first two moments of these estimators in terms of their product densities, and pay special attention to Poisson processes.  相似文献   

16.
Summary By introducing some parameters and estimating the weight coefficient, we give a new extension of Hilbert’s inequality with a best constant factor, which involves the β function. As its applications, we consider the equivalent form and some particular results.  相似文献   

17.
In this paper, we define a new weight function to represent a single-mode squeezed state. By means of this function, we shall be enabled to construct an interesting relationship between the total mean number of photons occupied a single-mode squeezed state and the mean free path of the atoms of the medium through which the natural light is diffused. This relationship assures the possibility to measure experimentally the average number of photons present in a single-mode squeezed state.  相似文献   

18.
In this paper, based on measure theoretical arguments, we establish Harnack estimates and Hölder continuity of nonnegative weak solutions for a degenerate parabolic equation with a singular weight. We transform the equation by performing the change of function. The energy estimates, the upper boundedness, the lower boundedness and the expansion of positivity for the solutions to the transformed equation are obtained. Then our aim is reached.  相似文献   

19.
In this paper, by estimating the weight function, we give a new Hilbert-type integral inequality whose kernel is a homogeneous form of degree −3 with the best constant factor and the reverse form is considered.  相似文献   

20.
通过对权数进行系统的研究,本文认为从"权数的性质"这个角度出发,权数具有"重要性"、"模糊性"、"主观性"和"时序性".将区域因素考虑进去,提出了权数具有"空间性","时空性"的观点.进一步,随着时间或区域的连续变化时,若权数也连续取值,则此时权数可以看成函数的形式,并给出两种具体的方法求权函数.特别针对权函数取值范围在0和1之间,将其进行函数变换后,通过新函数(权函数的Logit函数)的函数生成方法,进而得出权函数的生成方法.最后通过例子说明该方法比较符合权数的实际取值.  相似文献   

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