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1.
The signless Laplacian matrix of a graph is the sum of its diagonal matrix of vertex degrees and its adjacency matrix. Li and Feng gave some basic results on the largest eigenvalue and characteristic polynomial of adjacency matrix of a graph in 1979. In this paper, we translate these results into the signless Laplacian matrix of a graph and obtain the similar results.  相似文献   

2.
We study symmetric tensor spaces and cones arising from polynomial optimization and physical sciences.We prove a decomposition invariance theorem for linear operators over the symmetric tensor space,which leads to several other interesting properties in symmetric tensor spaces.We then consider the positive semidefiniteness of linear operators which deduces the convexity of the Frobenius norm function of a symmetric tensor.Furthermore,we characterize the symmetric positive semidefinite tensor(SDT)cone by employing the properties of linear operators,design some face structures of its dual cone,and analyze its relationship to many other tensor cones.In particular,we show that the cone is self-dual if and only if the polynomial is quadratic,give specific characterizations of tensors that are in the primal cone but not in the dual for higher order cases,and develop a complete relationship map among the tensor cones appeared in the literature.  相似文献   

3.
In the present paper, we find that the Bemstein-Durrmeyer operators, besides their better applications in approximation theory and some other fields, are good tools in constructing translation network. With the help of the de la Vallee properties of the Bernstein-Durrmeyer operators a sequence of translation network operators is constructed and its degree of approximation is dealt.  相似文献   

4.
The left semi-tensor product of matrices was proposed in [2]. In this paper the right semi-tensor product is introduced first. Some basic properties are presented and compared with those of the left semi-tensor product.Then two new applications are investigated. Firstly, its applications to connection, an important concept in differential geometry, is considered. The structure matrix and the Christoffel matrix are introduced. The transfer formulas under coordinate transformation are expressed in matrix form. Certain new results are obtained.Secondly, the structure of finite dimensional Lie algebra, etc. are investigated under the matrix expression. These applications demonstrate the usefulness of the new matrix products.  相似文献   

5.
Estimation in partial linear EV models with replicated observations   总被引:4,自引:0,他引:4  
The aim of this work is to construct the parameter estimators in the partial linear errors-in-variables (EV) models and explore their asymptotic properties. Unlike other related references, the assumption of known error covariance matrix is removed when the sample can be repeatedly drawn at each designed point from the model. The estimators of interested regression parameters, and the model error variance, as well as the non-parametric function, are constructed. Under some regular conditions, all of the estimators prove strongly consistent. Meanwhile, the asymptotic normality for the estimator of regression parameter is also presented. A simulation study is reported to illustrate our asymptotic results.  相似文献   

6.
PM环的扩张     
A ring is called PM-ring if every primitive ideal is a intersection of its some maximal ideals.In this paper,the property of PM-ring is discussed and the necessary and sufficient condition are given for the polynomial,centralizing,strongly normal extensions of PM-ring to be PM-rings.We also get some applications of the extension of PM-ring in group ring.  相似文献   

7.
Since Schoenberg's fundamental paper was published in 1946, the theory of polynomial spline functions developed rapldly and was rich in contents. Spline functions have wide range of applications to numerical approximation.But to certain functions, for example, to the function with singular points, the interpolation by polynomial spline is not always efficient and reasonable. Since 1973 some authors have investigated the rational spline functions, and abtained a lot of results. But  相似文献   

8.
Fractional factorial designs have played a prominent role in the theory and practice of experimental design.For designs with qualitative factors under an ANOVA model,the minimum aberration criterion has been frequently used;however,for designs with quantitative factors,a polynomial regression model is often established,thus theβ-wordlength pattern can be employed to compare different fractional factorial designs.Although theβ-wordlength pattern was introduced in 2004,its properties have not been investigated extensively.In this paper,we will present some properties ofβ-wordlength pattern for four-level designs.These properties can help find better designs with quantitative factors.  相似文献   

9.
张文俊 《数学季刊》1994,9(4):37-45
This paper is assigned to discuss the dynamics of a special class of polynomial automorphisms of C^N which was shown to be dense in the group of the polynomial automorphisms.We give some results about the analytic and geometric properties of the filled-in Julia set and the nonwandering set.We also make a characterization of the stable and unstable manifold for the filled-in Julia set.Furthermore,the number of the fixes points for such maps is studied.  相似文献   

10.
In this article, we introduce and characterize approximate duality for g-frames. We get some important properties and applications of approximate duals. We also obtain some new results in approximate duality of frames, and generalize some of the known results in approximate duality of frames to g-frames. We also get some results for fusion frames, and perturbation of approximately dual g-frames. We show that approximate duals are stable under small perturbations and they are useful for erasures and reconstruction.  相似文献   

11.
韩燕 《东北数学》2007,23(3):272-282
Due to its complexities in both mathematicM formulations and applications, universal co-kriging (UCK) has not been sufficiently discussed in literature. An extended and simpler matrix formulation UCK with incorporation of a polynomial variable trend is proposed in this paper. Estimators of the value and expectation of a regionMized vector taken in a point are obtained on the basis of cross-covaxiance and cross-vaxiogram, respectively. The complex expressions of co-kriging with trend are greatly simplified by introducing special matrix operations, such as Kronecker product, into the formulations. This simplification offers a feasible and easier approach for computer coding of the UCK, and helps the practitioners to use the UCK technique conveniently in real cases.  相似文献   

12.
We introduce first a sort of gray-scale morphological dilations and erosions, which might have some further applications in image analysis. Then we show that the dilation and the erosion defined here form adjunctive pairs. The duality between the dilation and the erosion and some other properties, such as the commuting property with translation and homothety, of these operators are discussed as well.  相似文献   

13.
Approximation by generalized MKZ-operators in polynomial weighted spaces   总被引:2,自引:0,他引:2  
We prove some approximation properties of generalized Meyer-Konig and Zeller operators for differentiable functions in polynomial weighted spaces. The results extend some results proved in [1-3,7-16].  相似文献   

14.
Comparison is made between the MINQUE and simple estimate of the error variance in the normal linear model under the nean square errors criterion,where the model matrix need not have full rank and the dispersion matrix can be singular.Our results show that any one of both estimates cannot be always superior to the other.Some sufficient criteria for any one of them to be better than the other are established.Some interesting relations between these two estimates are also given.  相似文献   

15.
Under the framework of the complex column-vector loop algebra ■~p,we propose a scheme for generating nonisospectral integrable hierarchies of evolution equations which generalizes the applicable scope of the Tu scheme.As applications of the scheme,we work out a nonisospectral integrable Schrodinger hierarchy and its expanding integrable model.The latter can be reduced to some nonisospectral generalized integrable Schrodinger systems,including the derivative nonlinear Schrodinger equation once obtained by Kaup and Newell.Specially,we obtain the famous Fokker-Plank equation and its generalized form,which has extensive applications in the stochastic dynamic systems.Finally,we investigate the Lie group symmetries,fundamental solutions and group-invariant solutions as well as the representation of the tensor of the Heisenberg group H_3 and the matrix linear group SL(2,R)for the generalized Fokker-Plank equation(GFPE).  相似文献   

16.
In this paper, the new subclass Bn( ,a,A,B) of analytic functions is introduced. Its subordination relations, inclusion relations, the inequality properties and convering theorem are discussed. The results obtained in this paper are sharp, which generalize the related works of some authors and some other new results are obtained.  相似文献   

17.
An extended fast algorithm for constructing the Dixon resultant matrix   总被引:1,自引:0,他引:1  
In recent years,the Dixon resultant matrix has been used widely in the re-sultant elimination to solve nonlinear polynomial equations and many researchers havestudied its efficient algorithms.The recursive algorithm is a very efficient algorithm,butwhich deals with the case of three polynomial equations with two variables at most.Inthis paper,we extend the algorithm to the general case of n 1 polynomial equations in nvariables.The algorithm has been implemented in Maple 9.By testing the random polyno-mial equations,the results demonstrate that the efficiency of our program is much betterthan the previous methods,and it is exciting that the necessary condition for the existenceof common intersection points on four general surfaces in which the degree with respectto every variable is not greater than 2 is given out in 48×48 Dixon matrix firstly by ourprogram.  相似文献   

18.
In this paper, we consider preconditioners for generalized saddle point systems with a nonsymmetric coefficient matrix. A constraint preconditioner for this systems is constructed, and some spectral properties of the preconditioned matrix are given. Our results extend the corresponding ones in [3] and [4].  相似文献   

19.
The mixed spin P-fields (MSP for short) theory sets up a geometric platform to relate Gromov-Witten invariants of the quintic three-fold and Fan-Jarvis-Ruan-Witten invariants of the quintic polynomial in five variables.It starts with Wittens vision and the P-fields treatment of GW invariants and FJRW invariants.Then it briefly discusses the master space technique and its application to the set-up of the MSP moduli.Some key results in MSP theory are explained and some examples are provided.  相似文献   

20.
In this paper,the so-called π-cover-avoiding properties of subgroups are defined and investigated.In terms of this property,we characterize the π-solvability of finite groups.Some other new results are also obtained based on the assumption that some subgroups have the semi cover-avoiding properties in a finite group.  相似文献   

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