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1.
In this paper, we mainly discuss the class of charming spaces. First, we show that there exists a charming space such that the Tychonoff product is not a charming space. Then we discuss some properties of charming spaces and give some characterizations of some class of charming spaces. Finally, we show that the Suslin number of an arbitrary charming rectifiable space is countable.  相似文献   

2.
The paper is devoted to the study of geodesic orbit Riemannian spaces that could be characterized by the property that any geodesic is an orbit of a 1-parameter group of isometries. In particular, we discuss some important totally geodesic submanifolds that inherit the property to be geodesic orbit. For a given geodesic orbit Riemannian space, we describe the structure of the nilradical and the radical of the Lie algebra of the isometry group. In the final part, we discuss some new tools to study geodesic orbit Riemannian spaces, related to compact Lie group representations with non-trivial principal isotropy algebras. We discuss also some new examples of geodesic orbit Riemannian spaces, new methods to obtain such examples, and some unsolved questions.  相似文献   

3.
根据胡固定教授经典集信息量定义给出一种新的模糊糊信息量度量方法,研究了其性质,并与Yager的特征测度进行了比较,表明该潮度是合理的.提出了模糊推理中蕴涵运算的信息度约束,给出了基于合成算法的模糊推理中,模糊蕴涵运算满足该信息度约束的充分条件.  相似文献   

4.
Mathematical models used for product positioning are proliferating at a rapid rate. To provide a structure to this research, we have categorized the models/algorithms into three basic approaches: utility functions, maps and trees. In this article we identify and discuss the recent advances related to these approaches, discuss data requirements and indicate issues that influence that choice of the particular product positioning approach best-suited for various situations.  相似文献   

5.
The paper is aimed at developing agent-based variants of traditional network models that make full use of concurrency. First, we review some classic models of the static structure of complex networks with the objective of developing agent-based models suited for simulating a large-scale, technology-enabled social network. Secondly, we outline the basic properties that characterize such networks. Then, we briefly discuss some classic network models and the properties of the networks they generate. Finally, we discuss how such models can be converted into agent-based models (i) to be executed more easily in heavily concurrent environments and (ii) to serve as basic blocks for more complex agent-based models. We evidence that many implicit assumptions made by traditional models regarding their execution environment are too expensive or outright impossible to maintain in concurrent environments. Consequently, we present the concurrency issues resulting from the violation of such assumptions. Then, we experimentally show that, under reasonable hypothesis, the agent-based variants maintain the main features of the classic models, notwithstanding the change of environment. Eventually, we present a meta-model that we singled out from the individual classic models and that we used to simplify the agent-oriented conversion of the traditional models. Finally, we discuss the software tools that we built to run the agent-based simulations.  相似文献   

6.
In the present paper we discuss a new clustering procedure in the case where instead of a single metric we have a family of metrics. In this case we can obtain a partially ordered graph of clusters which is not necessarily a tree. We discuss a structure of a hypergraph above this graph. We propose two definitions of dimension for hyperedges of this hypergraph and show that for the multidimensional p-adic case both dimensions are reduced to the number of p-adic parameters.We discuss the application of the hypergraph clustering procedure to the construction of phylogenetic graphs in biology. In this case the dimension of a hyperedge will describe the number of sources of genetic diversity.  相似文献   

7.
In this paper we discuss problems related to the value distribution of some special meromorphic functions in Clifford analysis. With a generalized Argument principle we describe orders of isolated a-points of a monogenic function. We prove a generalized version of Rouché's theorem. Further, we observe that the generalized elliptic functions in Clifford analysis play a special role with respect to value distributional questions. In particular, we discuss analogs to the classical Liouville theorems. The Argument principle will be exploited to show that the sum of the orders of all isolated a-points of a generalized elliptic function that has only isolated poles vanishes.  相似文献   

8.
The nonasymptotic method developed in Ref. 1 has been extended for solving general linear singularly perturbed two-point boundary-value problems. Firstly, we discuss problems with a right-hand boundary layer. Secondly, we discuss problems with an interior layer. Finally, we discuss problems with two boundary layers. Numerical experience with the method for some model problems is also reported to confirm the theoretical analysis.  相似文献   

9.
首先讨论了ICM公司职位分配到职员办公室的原则,并讨论了在这些原则下一个合理分配方案的合作网络和监管网络构成的混合网络模型;然后,利用该模型的节点属性、公司职员属性及两者之间的关系建立了后档案矩阵,讨论了公司职员属性函数,在此基础上研究了包含职员离职算法、内部升迁算法和外部招聘算法的动力学分析;最后,在混合网络模型中利用算法进行了动力学仿真。  相似文献   

10.
本文讨论了广义阿贝尔微分方程.利用不动点定理,得到了方程存在两个非零周期解的充分条件.同时,我们还讨论了不存在非零周期解和存在唯一非零周期解的情况.  相似文献   

11.
In this note, we establish several results concerning the gliding hump properties of matrix domains. In order to discuss F-WGHP, we introduce the UAK-property and find that this sort of property has close relationship with F-WGHP. In the course of discussing F-WGHP and WGHP of (C0)cn, we discuss the F-WGHP and WGHP of the almost-null sequence space f0.  相似文献   

12.
In this paper, we discuss examples of assignments for a course in discrete mathematics for undergraduate students majoring in business informatics. We consider several problems with computer-based solutions and discuss general strategies for using computers in teaching mathematics and its applications. In order to evaluate the effectiveness of our approach, we conducted an anonymous survey. The results of the survey provide evidence that our approach contributes to high outcomes and aligns with the course aims and objectives.  相似文献   

13.
Timo Reis  Matthias Voigt 《PAMM》2014,14(1):11-14
We discuss the infinite time-horizon linear-quadratic optimal control problem for differential-algebraic equations. In contrast to previous approaches we do not impose any assumptions on the system except for impulse controllability. In particular, we show that the optimal control problem is feasible if and only if a dissipation inequality has a solution. Moreover, we discuss conditions under which the problem has a minimizing (instead of only an infimizing) solution and furthermore, when this minimizing solution is unique. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

14.
In this paper, we consider the Riemann problem for a quasilinear hyperbolic system of equations governing the one dimensional unsteady simple wave flow of an isentropic, inviscid and perfectly conducting compressible fluid, subjected to a transverse magnetic field. This class of equations includes, as a special case, the equations of isentropic gasdynamics. We study the shock and rarefaction waves and their properties, and discuss the geometry of shock curves using the Riemann invariant coordinates. Under certain conditions, we show the existence and uniqueness of the solution to the Riemann problem for arbitrary initial data, and then discuss the vacuum state in isentropic magnetogasdynamics. Finally, we discuss numerical results for different initial data, and discuss all possible interactions of elementary waves. It is noticed that although the magnetogasdynamic system is more complex than the corresponding gasdynamic system, all the parallel results remain identical. However, unlike the ordinary gasdynamic case, the solution inside rarefaction waves in magnetogasdynamics cannot be obtained directly and explicitly; indeed, it requires an extra iteration procedure. It is also observed that the presence of a magnetic field makes both the shock and rarefaction stronger compared to what they would have been in the absence of a magnetic field.  相似文献   

15.
Our aim is to discuss how a visual display introduced in a classroom activity to represent a specific algebraic procedure is transformed, taking a central role and modifying the ongoing activity. To discuss how visualization comes about in this activity, we describe an illustrative example selected from observations carried out in a 9th grade classroom and analyze the class interaction from a cultural-historical perspective. Our analysis illuminates the tensions that emerge from a difference between the teacher’s way of signifying the algebraic procedure and the students’ overuse of a visual display they associate with it, and how these tensions impel changes in the activity. We further discuss some pros and cons of using visual displays in algebra classes, and we argue that it is very important for the teacher to be aware of them in order to realize the benefits of using such displays.  相似文献   

16.
针对一般的非线性规划问题,利用某些Lagrange型函数给出了一类Lagrangian对偶问题的一般模型,并证明它与原问题之间存在零对偶间隙.针对具体的一类增广La- grangian对偶问题以及几类由非线性卷积函数构成的Lagrangian对偶问题,详细讨论了零对偶间隙的存在性.进一步,讨论了在最优路径存在的前提下,最优路径的收敛性质.  相似文献   

17.
苏淳  刘杰  胡治水 《数学进展》2007,36(2):181-188
本文讨论完全区间树顶点数目Sx的大数律,所采用的方法不同于单边区间树.文章包括三部分内容:首先探讨完全区间树所得以定义的概率空间,弄清楚它的结构,为强大数律的研究奠定理论基础.接着,针对完全区间树上的Sx的矩母函数不易求得的情况,另辟蹊径,求得Sx的期望和方差.最后,给出Sx的强弱大数律.  相似文献   

18.
Recently Dritschel proved that any positive multivariate Laurent polynomial can be factorized into a sum of square magnitudes of polynomials. We first give another proof of the Dritschel theorem. Our proof is based on the univariate matrix Fejér–Riesz theorem. Then we discuss a computational method to find approximates of polynomial matrix factorization. Some numerical examples will be shown. Finally we discuss how to compute nonnegative Laurent polynomial factorizations in the multivariate setting.  相似文献   

19.
张相虎  边平勇 《经济数学》2007,24(2):130-133
将多险种风险模型推广到带干扰项的一种新模型,讨论了收益过程的性质,并利用鞅的方法得出了破产概率所满足的Lundberg不等式及其一般公式.  相似文献   

20.
弱Galois扩张与反Smash积   总被引:1,自引:0,他引:1  
陈惠香 《数学学报》1998,41(6):0-1172
本文对(H,K)-余模代数A,讨论了弱Galois扩张A/C,证明了k的每个自由二次扩张是弱Galois扩张.并利用反Smash积#op(K,A)与K-余不变子代数C之间的Morita联系讨论A的投射性、Galois扩张及其传递性.  相似文献   

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