Trees, parking functions, syzygies, and deformations of monomial ideals

For a graph , we construct two algebras whose dimensions are both equal to the number of spanning trees of . One of these algebras is the quotient of the polynomial ring modulo certain monomial ideal, while the other is the quotient of the polynomial ring modulo certain powers of linear forms. We describe the set of monomials that forms a linear basis in each of these two algebras. The basis elements correspond to -parking functions that naturally came up in the abelian sandpile model. These ideals are instances of the general class of monotone monomial ideals and their deformations. We show that the Hilbert series of a monotone monomial ideal is always bounded by the Hilbert series of its deformation. Then we define an even more general class of monomial ideals associated with posets and construct free resolutions for these ideals. In some cases these resolutions coincide with Scarf resolutions. We prove several formulas for Hilbert series of monotone monomial ideals and investigate when they are equal to Hilbert series of deformations. In the appendix we discuss the abelian sandpile model.

     

光纤智能结构中的光纤联接

光纤能以多种不同的构造方式集成并埋入复合材料中来构成可使用的智能结构,但如果没有有效的光纤联接技术,所有的埋入能力和传感器活动就找不到在实际可行的结构中去应用。文章作者对光纤智能结构中光纤互联问题按光纤联接的要求,光学联接法与装置、联接器件设计三方面进行了探讨。     

Expected Sums of General Parking Functions

A (u₁, u₂, . . . )-parking function of length n is a sequence (x₁, x₂, . . . , x_n) whose order statistics (the sequence (x₍₁₎, x₍₂₎, . . . , x_(n)) obtained by rearranging the original sequence in non-decreasing order) satisfy x_(i) u_(i). The Gonarov polynomials g _n (x; a₀, a ₁, . . . , a _n-1) are polynomials biorthogonal to the linear functionals (a _i) Dⁱ, where (a) is evaluation at a and D is differentiation. In this paper, we give explicit formulas for the first and second moments of sums of u-parking functions using Gonarov polynomials by solving a linear recursion based on a decomposition of the set of sequences of positive integers. We also give a combinatorial proof of one of the formulas for the expected sum. We specialize these formulas to the classical case when u _i=a+ (i-1)b and obtain, by transformations with Abel identities, different but equivalent formulas for expected sums. These formulas are used to verify the classical case of the conjecture that the expected sums are increasing functions of the gaps u_i+1 - u_i. Finally, we give analogues of our results for real-valued parking functions.AMS Subject Classification: 05A15, 05A19, 05A20, 05E35.     

基于Petri网的多Agent行为协进化模型研究

协进化方法是解决多Agent控制系统在动态、开放环境下行为协调协作自适应问题的新途径。针对多Agent行为协进化过程的实现,采用Petri网方法研究并构建了多Agent行为协进化过程模型,对模型进行了特性分析及仿真验证。所建模型较好地描述了协进化过程的流程结构和动态行为规律,为系统的分析及实现奠定了基础。     

面向机构的智能文本分析系统的研究

随着电子文本信息在机构内部的快速增加,人们无法应对堆积如山的文档,许多文档无法实现其信息价值,如何充分利用这些文本信息资源已成为一个迫切需要解决的问题。介绍一种可用于机构内部的智能文本分析系统以及相关的关键技术,其功能包括文档检索、文档自动摘要和话题自动识别与跟踪。利用智能文本分析系统能够充分实现文本文档的信息价值。     

智能测控仪表系统的CAN总线通信方案

在分析了CAN现场总线特点的基础上提出了智能测控仪表系统的CAN总线通信方案。然后分别以内嵌CAN控制器的DSP芯片TMS320LF2407和CAN232智能CAN接口卡为例说明了它们与CAN总线通信的工程实现方法。     

移动代理在智能电子商务中的建模分析

从电子商务的概念出发,分析了移动代理技术和智能电子商务的关系,同时提出了使用代理技术的电子商务概念模型;并按照这一概念设计了一个以Aglet为代理平台的网上交易系统的实现模型。     

Initial guess by improved population-based intelligent algorithms for large inter-frame deformation measurement using digital image correlation

Digital image correlation (DIC) has received a widespread research and application in experimental mechanics. In DIC, the performance of subpixel registration algorithm (e.g., Newton-Raphson method, quasi-Newton method) relies heavily on the initial guess of deformation. In the case of small inter-frame deformation, the initial guess could be found by simple search scheme, the coarse-fine search for instance. While for large inter-frame deformation, it is difficult for simple search scheme to robustly estimate displacement parameters and deformation parameters simultaneously with low computational cost. In this paper, we proposed three improving strategies, i.e. Q-stage evolutionary strategy (T), parameter control strategy (C) and space expanding strategy (E), and then combined them into three population-based intelligent algorithms (PIAs), i.e. genetic algorithm (GA), differential evolution (DE) and particle swarm optimization (PSO), and finally derived eighteen different algorithms to calculate the initial guess for qN. The eighteen algorithms were compared in three sets of experiments including large rigid body translation, finite uniaxial strain and large rigid body rotation, and the results showed the effectiveness of proposed improving strategies. Among all compared algorithms, DE-TCE is the best which is robust, convenient and efficient for large inter-frame deformation measurement.     

OTT 系统在三网融合背景下的推行

随着三网融合的日渐加速，OTT系统已成为业界炙手可热的平台和方案。 OTT提供了基于IP网络的跨屏全业务运营平台，将传统电视收视扩展到IP网络领域。 OTT平台将原本独立的DVB平台与Internet平台联系起来，发挥桥梁的作用，促进了平台间的业务与信息的交换。阐述三网融合背景下OTT系统的方案、功能及未来发展方向。     

移动预付费智能业务

对移动预付费智能业务的概念、系统结构、业务功能、事务处理流程、链路配置等进行了分析。