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多项集元素的hash_tree快速查找方法 被引量:2
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作者 曾传璜 郑剑 邵利平 《南方冶金学院学报》 2003年第5期41-43,共3页
为了解决传统的hash查找无法对元素是多项集结构进行有效的处理,提出了一种基于hash查找和树(tree)结构的hash_tree快速查找方法.
关键词 散列查找 多项集 hash-tree查找
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关系数据库多项集关联规则挖掘的探讨
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作者 李力 朱天翔 许占文 《沈阳工业大学学报》 EI CAS 1998年第5期26-29,共4页
关联规则挖掘是数据挖掘领域的重要技术.在分析关联规则和广义关联规则的基本模型的基础上,提出了关系数据库中多项集关联规则的基本模型,对多项集关联规则挖掘方法进行了探讨.
关键词 数据挖掘 关联规则 多项集 关系数据库
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调查问卷回答缺项对交通方式选择模型的影响:发展中国家城市的比较分析 被引量:1
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作者 李纲 藤原章正 张峻屹 《交通运输系统工程与信息》 EI CSCD 2011年第4期61-76,共16页
为提高交通规划与决策质量,有必要妥善处理交通调查无回答问题.但是在相关研究中尤其在发展中国家此问题常被忽视.本文统计分析了发展中城市居民出行调查中项目无回答的缺失模式,进一步分析项目无回答作为模型缺失数据对基于期望最大化... 为提高交通规划与决策质量,有必要妥善处理交通调查无回答问题.但是在相关研究中尤其在发展中国家此问题常被忽视.本文统计分析了发展中城市居民出行调查中项目无回答的缺失模式,进一步分析项目无回答作为模型缺失数据对基于期望最大化的数据修补的多项Logit集计的出行方式选择模型的影响.选择三个发展中城市代表调查无回答的三个等级做案例分析.首先,根据项目无回答缺失模式,利用Pearson开方检验得出重要的出行者社会经济属性和出行背景因素.其次,利用基于缺失模式分析的期望最大化估计,处理缺失数据得到无偏数据集作为基准.此外,利用独立样本的T检验检验了零假设,即有无期望最大化估计情况下的模型参数估计是相同的.用基于R平方系数的内在效度检验计算估计情况下的模型预测偏差.最后,考虑缺失数据的影响,评估一个重要的指标——出行时间价值.结果表明,在发展中城市,问卷回答者和不回答者的社会经济背景存在很大差异.缺失率和缺失模式均对出行方式选择模型的参数和预测精度有很大影响.考虑缺失模式的出行时间价值计算表明,项目无回答对出行时间价值的影响被过高估计了. 展开更多
关键词 城市交通 缺失模式 期望最大化修补方法 出行方式选择 多项Logit计模型 发展中城市 出行时间价值
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NOTE ON FORMULATION OF GEOMETRIC PROPERTIES OF A POLYNOMIAL SYSTEM
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作者 郦志新 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期203-207,共5页
This note shows that when studying geometric pro perties, a polynomial system is defined as a line field on a projective space such that its singular set has co dimension at least 2. By this definition, the concept ... This note shows that when studying geometric pro perties, a polynomial system is defined as a line field on a projective space such that its singular set has co dimension at least 2. By this definition, the concept of the degree of a polynomial system does not coincide with the usual one. The usual degenerate polynomial system of degree n+1 should be regarded as a system of degree n . Note that the definition is independent coordinate system. And, by this definition, some geometric properties concerning polynomial vector fields turn out to be evident. 展开更多
关键词 polynomial vector fields line fields geome tric properties
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Ferrers Matrices Characterized by the Rook Polynomials
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作者 MA Hai-cheng,HU Sheng-biao(Department of Mathematics , Qinghai Nationalities College , Xining 810007, China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期163-167,共5页
In this paper,we show that there exist precisely W(A) Ferrers matrices F(C1,C2,…,cm)such that the rook polynomials is equal to the rook polynomial of Ferrers matrix F(b1,b2,…,bm), where A={b1,b2-1,…,bm-m+1} is a re... In this paper,we show that there exist precisely W(A) Ferrers matrices F(C1,C2,…,cm)such that the rook polynomials is equal to the rook polynomial of Ferrers matrix F(b1,b2,…,bm), where A={b1,b2-1,…,bm-m+1} is a repeated set,W(A) is weight of A. 展开更多
关键词 rook polynomial Ferrers matrix repeated set
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On Total Domination Polynomials of Certain Graphs
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作者 S. Sanal H. E. Vatsalya 《Journal of Mathematics and System Science》 2016年第3期123-127,共5页
We have introduced the total domination polynomial for any simple non isolated graph G in [7] and is defined by Dt(G, x) = ∑in=yt(G) dr(G, i) x', where dr(G, i) is the cardinality of total dominating sets of... We have introduced the total domination polynomial for any simple non isolated graph G in [7] and is defined by Dt(G, x) = ∑in=yt(G) dr(G, i) x', where dr(G, i) is the cardinality of total dominating sets of G of size i, and yt(G) is the total domination number of G. In [7] We have obtained some properties of Dt(G, x) and its coefficients. Also, we have calculated the total domination polynomials of complete graph, complete bipartite graph, join of two graphs and a graph consisting of disjoint components. In this paper, we presented for any two isomorphic graphs the total domination polynomials are same, but the converse is not true. Also, we proved that for any n vertex transitive graph of order n and for any v ∈ V(G), dt(G, i) = 7 dt(V)(G, i), 1 〈 i 〈 n. And, for any k-regular graph of order n, dr(G, i) = (7), i 〉 n-k and d,(G, n-k) = (kn) - n. We have calculated the total domination polynomial of Petersen graph D,(P, x) = 10X4 + 72x5 + 140x6 + 110x7 + 45x8 + [ 0x9 + x10. Also, for any two vertices u and v of a k-regular graph Hwith N(u) ≠ N(v) and if Dr(G, x) = Dt( H, x ), then G is also a k-regular graph. 展开更多
关键词 total dominating set total domination number total domination polynomial
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On Dickson Polynomials and Difference Sets
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作者 曹喜望 丘维声 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2006年第2期219-226,共8页
In 1998, Maschietti constructed several cyclic difference sets from monomial hyperovals. R. Evans, H.D.L. Holloman, C. Krattnthaler and Qing Xiang gave an algebraic proof of the two autocorrelation property of the rel... In 1998, Maschietti constructed several cyclic difference sets from monomial hyperovals. R. Evans, H.D.L. Holloman, C. Krattnthaler and Qing Xiang gave an algebraic proof of the two autocorrelation property of the related binary sequence. In this paper, we show that hyperovals are very closely related to two-to-one maps, and then we proceed to generalize Maschietti's result. 展开更多
关键词 cyclic difference sets permutation polynomials hyperovals two-to-one maps binary sequences.
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Asymptotics for partly linear regression with dependent samples and ARCH errors:consistency with rates 被引量:3
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作者 卢祖帝 I.Gijbels 《Science China Mathematics》 SCIE 2001年第2期168-183,共16页
Partly linear regression model is useful in practice, but littleis investigated in the literature to adapt it to the real data which are dependent and conditionally heteroscedastic. In this paper, the estimators of th... Partly linear regression model is useful in practice, but littleis investigated in the literature to adapt it to the real data which are dependent and conditionally heteroscedastic. In this paper, the estimators of the regression components are constructed via local polynomial fitting and the large sample properties are explored. Under certain mild regularities, the conditions are obtained to ensure that the estimators of the nonparametric component and its derivatives are consistent up to the convergence rates which are optimal in the i.i.d. case, and the estimator of the parametric component is root-n consistent with the same rate as for parametric model. The technique adopted in the proof differs from that used and corrects the errors in the reference by Hamilton and Truong under i.i.d. samples. 展开更多
关键词 ARCH (GARCH) errors dependent samples local polynomial fitting convergence rates partly linear model root-n consistency
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A CRITERION FOR TESTING WHETHER A DIFFERENCE IDEAL IS PRIME
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作者 Chunming YUAN Xiao-Shan GAO Key Laboratory of Mathematics Mechanization,Institute of Systems Science Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,China. 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2009年第4期627-635,共9页
This paper presents a criterion for testing the irreducibility of a polynomial over an algebraicextension field.Using this criterion and the characteristic set method,the authors give a criterion fortesting whether ce... This paper presents a criterion for testing the irreducibility of a polynomial over an algebraicextension field.Using this criterion and the characteristic set method,the authors give a criterion fortesting whether certain difference ascending chains are strong irreducible,and as a consequence,whetherthe saturation ideals of these ascending chains are prime ideals. 展开更多
关键词 Characteristic set difference prime ideal IRREDUCIBILITY strong irreducibility.
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On Univalence of the Power Deformation z(f(z)/z)c
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作者 Yong Chan KIM Toshiyuki SUGAWA 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2012年第6期823-830,共8页
The authors mainly concern the set Uf of c E C such that the power deformation z(f-(z)/z)c is univalent in the unit disk |z|〈 1 for a given analytic univalent function f(z) = z + a2z2 + ... in the unit disk... The authors mainly concern the set Uf of c E C such that the power deformation z(f-(z)/z)c is univalent in the unit disk |z|〈 1 for a given analytic univalent function f(z) = z + a2z2 + ... in the unit disk. It is shown that Uf is a compact, polynomially convex subset of the complex plane C unless f is the identity function. In particular, the interior of Uf is simply connected. This fact enables us to apply various versions of the X-lemma for the holomorphic family z(f(z)/z)c of injections parametrized over the interior of Uf. The necessary or sufficient conditions for Uf to contain 0 or 1 as an interior point are also given. 展开更多
关键词 Univalent function Holomorphic motion Quasiconformal extension Grunsky inequality Univalence criterion
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Equality-constrained minimization of polynomial functions
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作者 XIAO ShuiJing ZENG GuangXing 《Science China Mathematics》 SCIE CSCD 2015年第10期2181-2204,共24页
This paper investigates the equality-constrained minimization of polynomial functions. Let R be the field of real numbers, and R[x1,..., xn] the ring of polynomials over R in variables x1,..., xn. For an f ∈ R[x1,...... This paper investigates the equality-constrained minimization of polynomial functions. Let R be the field of real numbers, and R[x1,..., xn] the ring of polynomials over R in variables x1,..., xn. For an f ∈ R[x1,..., xn] and a finite subset H of R[x1,..., xn], denote by V(f : H) the set {f( ˉα) | ˉα∈ Rn, and h( ˉα) =0, ? h ∈ H}. We provide an effective algorithm for computing a finite set U of non-zero univariate polynomials such that the infimum inf V(f : H) of V(f : H) is a root of some polynomial in U whenever inf V(f : H) = ±∞.The strategies of this paper are decomposing a finite set of polynomials into triangular chains of polynomials and computing the so-called revised resultants. With the aid of the computer algebraic system Maple, our algorithm has been made into a general program to treat the equality-constrained minimization of polynomials with rational coefficients. 展开更多
关键词 polynomial function equality constraints equality-constrained minimization constrained infimum Wu’s algorithm triangular decompo
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A Triangular Decomposition Algorithm for Differential Polynomial Systems with Elementary Computation Complexity 被引量:1
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作者 ZHU Wei GAO Xiao-Shan 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2017年第2期464-483,共20页
In this paper, a new triangular decomposition algorithm is proposed for ordinary differential polynomial systems, which has triple exponential computational complexity. The key idea is to eliminate one algebraic varia... In this paper, a new triangular decomposition algorithm is proposed for ordinary differential polynomial systems, which has triple exponential computational complexity. The key idea is to eliminate one algebraic variable from a set of polynomials in one step using the theory of multivariate resultant. This seems to be the first differential triangular decomposition algorithm with elementary computation complexity. 展开更多
关键词 Differential polynomial system regular triangular set saturated triangular set triangular decomposition.
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Generating Semi-Algebraic Invariants for Non-Autonomous Polynomial Hybrid Systems 被引量:1
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作者 WANG Qiuye LI Yangjia +1 位作者 XIA Bican ZHAN Naijun 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2017年第1期234-252,共19页
Hybrid systems are dynamical systems with interacting discrete computation and continuous physical processes, which have become more common, more indispensable, and more complicated in our modern life. Particularly, m... Hybrid systems are dynamical systems with interacting discrete computation and continuous physical processes, which have become more common, more indispensable, and more complicated in our modern life. Particularly, many of them are safety-critical, and therefore are required to meet a critical safety standard. Invariant generation plays a central role in the verification and synthesis of hybrid systems. In the previous work, the fourth author and his coauthors gave a necessary and sufficient condition for a semi-algebraic set being an invariant of a polynomial autonomous dynamical system, which gave a confirmative answer to the open problem. In addition, based on which a complete algorithm for generating all semi-algebraic invariants of a given polynomial autonomous hybrid system with the given shape was proposed. This paper considers how to extend their work to non-autonomous dynamical and hybrid systems. Non-autonomous dynamical and hybrid systems are with inputs, which are very common in practice; in contrast, autonomous ones are without inputs. Furthermore, the authors present a sound and complete algorithm to verify semi-algebraic invariants for non-autonomous polynomial hybrid systems. Based on which, the authors propose a sound and complete algorithm to generate all invariants with a pre-defined template. 展开更多
关键词 Hybrid systems INVARIANTS NON-A utonomous systems polynomial ideals semi-algebraic sets.
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Operational Solution to the Nonlinear Klein-Gordon Equation
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作者 G.Bengochea L.Verde-Star M.Ortigueira 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第5期506-512,共7页
We obtain solutions of the nonlinear Klein-Gordon equation using a novel operational method combined with the Adomian polynomial expansion of nonlinear functions. Our operational method does not use any integral trans... We obtain solutions of the nonlinear Klein-Gordon equation using a novel operational method combined with the Adomian polynomial expansion of nonlinear functions. Our operational method does not use any integral transforms nor integration processes. We illustrate the application of our method by solving several examples and present numerical results that show the accuracy of the truncated series approximations to the solutions. 展开更多
关键词 operational calculus partial differential equations nonlinear Klein-Gordon equation
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THE TOPOLOGY OF JULIA SETS FOR GEOMETRICALLY FINITE POLYNOMIALS 被引量:1
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作者 YIN YONGCHENG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1998年第1期77-80,共4页
By means of the Branner-Hubbard puzzle, the author studies the topology of filled-in Julia sets for geometrically finite polynomials,and proves a conjecture of C. McMullen and a conjecture of B. Branner and J. H. Hu... By means of the Branner-Hubbard puzzle, the author studies the topology of filled-in Julia sets for geometrically finite polynomials,and proves a conjecture of C. McMullen and a conjecture of B. Branner and J. H. Hubbard partially. 展开更多
关键词 Filled-in Julia set Geometrically finite polynomial TOPOLOGY
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