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1.
AMETHODFORMECHANICALGEOMETRYTHEOREMPROVING¥WUJinzhao(InstituteofSystemsScience,AcademiaSinica,Beijing100080,China)TANHongyan(...  相似文献   

2.
ONTHEALGEBRAICVARIETYDECOMPOSITIONWUJinzhao(InstituteofSystemsScience,AcademiaSinica,Beijing100080,China)ONTHEALGEBRAICVARIET...  相似文献   

3.
仿真结果与试验数据的一致性研究   总被引:5,自引:0,他引:5  
给出了判断作战仿真结果与战史数据是否一致的参考准则,及通过仿真结果和试验数据的比较判断仿真模型有效性的方法。  相似文献   

4.
Gao,Volny and Wang(2010) gave a simple criterion for signature-based algorithms to compute Grobner bases.It gives a unified frame work for computing Grobner bases for both ideals and syzygies,the latter is very important in free resolutions in homological algebra.Sun and Wang(2011) later generalized the GVW criterion to a more general situation(to include the F5 Algorithm).Signature-based algorithms have become increasingly popular for computing Grobner bases.The current paper introduces a concept of factor pairs that can be used to detect more useless J-pairs than the generalized GVW criterion,thus improving signature-based algorithms.  相似文献   

5.
As a consequence of a previons study of algebraic differential geometry(see [WU1]) theremay be associated to certain special kinds of differential ideals some well-behaved basis enjoyingsome well-behaved properties.If the differential ideals are further specialized so that theycorrespond to ordinary polynomial ideals then such a well-behaved basis will become the usualGroebner basis of the polynomial ideals while the latter is not known for differential ideals.  相似文献   

6.
Model update mechanism for mean-shift tracking   总被引:1,自引:0,他引:1  
1.INTRODUCTION Theefficientandrobusttrackingofobjectintheim agesequencesisalwaysachallengingtaskforcomput ervision.Mostoftheapplicationssuchassurveillance andmonitoringrequirethetrackershouldberobustto occlusion,changesinobjectappearanceandcamera positionincomplexenvironments.Recently,the mean shiftalgorithmiswidelyinthetrackingappli cation[1~4].Itisaneficientwaytolocateobject withoutdoingexhaustivesearch.Therefore,wepay moreattentiontothemodelupdateissuethatplaysan importantroleinrob…  相似文献   

7.
8.
1. INTanDUCTIONIn recent years, a number of research efforts have been made on stability analysis ed design for large-scaletime--delay systems. Hmamed [1] adopted a generalized linear system model and solxred the complex LyaPu-novequation to obtain the main results. Mori, et al.[2I worked ont a stability criterion for large--scale systemswith time delays by using comparison methods and M--matrix properties. Suh and Bien [3l and Lewis andAnderson [4] deve1oped some stability criteria for…  相似文献   

9.
基于模糊控制的最大功率点跟踪的仿真研究   总被引:4,自引:0,他引:4  
在Matlab仿真环境下建立了一个基于Boost拓扑的光伏充电器,并且引入模糊控制技术对该仿真模型进行最大功率点跟踪(MPPT)控制。不仅从标准测试条件、光照突变这两种情况来比较模糊控制跟踪策略与爬坡法、电导增量法的区别,还从温度持续上升、光照持续上升、采样时间间隔这三方面,对三种跟踪策略进行比较,能够更全面地证明模糊控制跟踪策略在响应速度以及稳定性上优于爬坡法和电导增量法。  相似文献   

10.
TOWARDS REAL-TIME CUSTOMIZED MANAGEMENT OF SUPPLY AND DEMAND CHAINS   总被引:1,自引:1,他引:0  
Our focus herein is on developing an effective taxonomy for the simultaneous and real-timemanagement of supply and demand chains.More specifically,the taxonomy is developed in terms ofits underpinning components and its research foci.From a components perspective,we first considerthe value chain of supplier,manufacturer,assembler,retailer,and customer,and then develop aconsistent set of definitions for supply and demand chains based on the location of the customer orderpenetration point.From a research perspective,we classify the methods that are employed in themanagement of these chains,based on whether supply and/or demand are flexible or fixed.Interestingly,our taxonomy highlights a very critical research area at which both supply and demandare flexible,thus manageable.Simultaneous management of supply and demand chains sets the stagefor mass customization which is concerned with meeting the needs of an individualized customermarket.Simultaneous and real-time management of supply and demand chains set  相似文献   

11.
Gr?bner basis theory for parametric polynomial ideals is explored with the main objective of mimicking the Gr?bner basis theory for ideals. Given a parametric polynomial ideal, its basis is a comprehensive Gr?bner basis if and only if for every specialization of its parameters in a given field, the specialization of the basis is a Gr?bner basis of the associated specialized polynomial ideal.For various specializations of parameters, structure of specialized ideals becomes qualitatively different even though there are significant relationships as well because of finiteness properties. Key concepts foundational to Gr?bner basis theory are reexamined and/or further developed for the parametric case:(i) Definition of a comprehensive Gr?bner basis,(ii) test for a comprehensive Gr?bner basis,(iii) parameterized rewriting,(iv) S-polynomials among parametric polynomials,(v) completion algorithm for directly computing a comprehensive Gr?bner basis from a given basis of a parametric ideal. Elegant properties of Gr?bner bases in the classical ideal theory, such as for a fixed admissible term ordering,a unique Gr?bner basis can be associated with every polynomial ideal as well as that such a basis can be computed from any Gr?bner basis of an ideal, turn out to be a major challenge to generalize for parametric ideals; issues related to these investigations are explored. A prototype implementation of the algorithm has been successfully tried on many examples from the literature.  相似文献   

12.
In this paper, the so-called invertibility is introduced for rational univariate representations, and a characterization of the invertibility is given. It is shown that the rational univariate representations, obtained by both Rouillier’s approach and Wu’s method, are invertible. Moreover, the ideal created by a given rational univariate representation is defined. Some results on invertible rational univariate representations and created ideals are established. Based on these results, a new appr...  相似文献   

13.
Gröbner basis theory for parametric polynomial ideals is explored with the main objective of mimicking the Gröbner basis theory for ideals. Given a parametric polynomial ideal, its basis is a comprehensive Gröbner basis if and only if for every specialization of its parameters in a given field, the specialization of the basis is a Gröbner basis of the associated specialized polynomial ideal. For various specializations of parameters, structure of specialized ideals becomes qualitatively different even though there are significant relationships as well because of finiteness properties. Key concepts foundational to Gröbner basis theory are reexamined and/or further developed for the parametric case: (i) Definition of a comprehensive Gröbner basis, (ii) test for a comprehensive Gröbner basis, (iii) parameterized rewriting, (iv) S-polynomials among parametric polynomials, (v) completion algorithm for directly computing a comprehensive Gröbner basis from a given basis of a parametric ideal. Elegant properties of Gröbner bases in the classical ideal theory, such as for a fixed admissible term ordering, a unique Gröbner basis can be associated with every polynomial ideal as well as that such a basis can be computed from any Gröbner basis of an ideal, turn out to be a major challenge to generalize for parametric ideals; issues related to these investigations are explored. A prototype implementation of the algorithm has been successfully tried on many examples from the literature.  相似文献   

14.
估计Verhulst 模型中参数的线性规划方法及应用   总被引:9,自引:2,他引:9  
估计灰色Verhulst模型中的参数通常采用最小二乘准则,而在模型精度检验时又经常采用平均相对误差.本文主要在平均相对误差达到最小准则或最大相对误差达到最小准则下,阐明了Verhulst模型中参数估计问题可转化为线性规划问题,可以利用线性规划方法估计Verhulst模型中的参数.实际应用表明本文的方法是可行的且有效的,比传统方法预测精度高.  相似文献   

15.
It is already known that there are several nonlinearity criteria such as algebraic degree, nonlinearity,distance to linear structures, correlation immune, propagationcriterion, differential uniformity,which are used to check whether a cryptographic functionis weak or not. In this paper we will discuss these criteria from a valuation point of view,and consider the largest transformation group which leave a criterion invariant, which isnamed its symmetry group. It can serve as a way of comparing the stability of nonlinearitycriteria under the action of invertible transformations.  相似文献   

16.
基于客观系统分析的解释结构模型   总被引:10,自引:0,他引:10  
用解释结构模型(ISM)进行系统分析的关键是准确确定系统要素的邻接矩阵。基于OSA的ISM模型是利用自组织的客观系统分析(OSA)方法在训练集上产生复杂度逐渐增加的模型,用检验集筛选模型,系统外准则值的最小值对应着最优方程组。最优方程组以定量的方式给出系统变量间的连接方法和连接强度。根据OSA最优方程组中变量之间的系数是否为0或通过设定阈值可以客观地确定邻接矩阵。在此基础上建立的ISM模型从整体角度准确地揭示了系统要素的结构,是实现系统知识提取的有效途径。  相似文献   

17.
带全局判据的改进量子粒子群优化算法   总被引:1,自引:0,他引:1  
针对现有量子粒子群优化算法的多参数(≥5)优化问题易收敛到局部最优解、且无法判定优化结果全局性的问题,提出了带全局判据的改进量子粒子群优化算法。在惯性权重自适应调整的量子粒子群优化算法基础上,进行了粒子位置周期性变异,以及随粒子进化速度和聚集度变化的搜索范围变异。依据粒子聚集度大小,建立了判定优化结果全局性的全局收敛判据。以典型标准函数和乘波体外形多参数优化问题为算例,验证了改进算法和全局判据的可靠性。结果表明,改进算法的全局搜索能力明显提高,优化结果真实可靠,全局判据实用性强。  相似文献   

18.
Manufacturing and services: From mass production to mass customization   总被引:3,自引:1,他引:2  
Manufacturing and services constitute two of the five sectors of every country’s economy;depending on the maturity of the economy,they are-in terms of employment-typically the two largest sectors.The outputs or products of an economy can also be divided into goods products(due to manufacturing,construction,agriculture and mining) and services products.To date,the goods and services products have,for the most part,been mass produced;it is the premise of this paper that recent technological advances-including flexible manufacturing,cloud computing,nanotechnology and smart sensing-can better enable the transformation from mass production to mass customization.We regard mass customization as the simultaneous and real time management of supply and demand chains,based on a taxonomy that can be defined in terms of its underpinning component and management foci.From a components perspective,we first consider the value chain of supplier,manufacturer,assembler,retailer,and customer,and then develop a consistent set of definitions for supply and demand chains based on the location of the customer order penetration point.From a management perspective,we classify the methods that are employed in the management of these chains,based on whether supply and/or demand are flexible or fixed.Interestingly,our management taxonomy highlights a very critical research area at which both supply and demand are flexible,thus manageable.Simultaneous management of supply and demand chains sets the stage for mass customization which is concerned with meeting the needs of an individualized customer market.Simultaneous and real time management of supply and demand chains set the stage for real time mass customization(e.g.,wherein a tailor first laser scans an individual’s upper torso and then delivers a uniquely fitted jacket within a reasonable period,while the individual is waiting).The benefits of real time mass customization cannot be over-stated as goods and services become indistinguishable and are co-produced-as "servgoods"-in real time,resulting in an overwhelming economic advantage.  相似文献   

19.
Information structures and pricing decisions in competing supply chains   总被引:1,自引:1,他引:0  
The paper investigates the pricing decisions of two competing supply chains under the different information structures. Each retailer has private information about the market demand and has the right to decide whether or not to share the information with the manufacturer. Three demand-information structures, i.e., information sharing in both supply chains, information sharing in only one supply chain and information sharing in neither supply chain, are considered. We investigate the value of information by comparing the information structures, and find that the information value not only works in the channel directly, but also does in the competing channel indirectly. Information sharing in a supply chain always benefits its manufacturer, but hurts its retailer; while it benefits both the manufacturer and the retailer of competing supply chain, regardless of whether this competing supply chain has information sharing. From the perspective of channel, when the competition is more intense, information sharing in a supply chain makes this supply chain better off, and when the competition is less intense, the information sharing in a supply chain makes this supply chain worse off. However, it always makes the competing supply chain better off regardless of whether the competing supply chain has information sharing.  相似文献   

20.
研究不同价格的同类零部件的归并问题。以总购置成本最低为目标,建立了针对两种不同价格的同类零部件的归并模型,提出了零部件归并的条件。在此基础上,用参数示例法分析了零部件需求量、采购价格差异、购置成本结构等因素对零部件归并的影响,并对企业的零部件归并管理提出了一些具体的建议。  相似文献   

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