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The Lower Orders of Dirichlet and Random Dirichlet Series 被引量:7
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作者 Yu Jiarong (Department of Mathematics,Wuhan University,Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期1-8,共8页
The formulas of the lower orders of Dirichlet series are given by means of the exponents and the convex regularized sequences of the logarithms and the convex regularized sequences of the logarithms of the moduli of t... The formulas of the lower orders of Dirichlet series are given by means of the exponents and the convex regularized sequences of the logarithms and the convex regularized sequences of the logarithms of the moduli of the coefficients. Corresponding results are obtained for some random Dirichlet series. 展开更多
关键词 Dirichlet series random Dirichlet series lower order convex regularization
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THE LOWER ORDER AND LINEAR ORDER OF MULTIPLE DIRICHLET SERIES 被引量:4
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作者 梁美丽 霍颖莹 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期131-138,共8页
The article investigates the growth of multiple Dirichlet series.The lower order and the linear order of n-tuple Dirichlet series in Cn are defined and some relations between them and the coefficients and exponents of... The article investigates the growth of multiple Dirichlet series.The lower order and the linear order of n-tuple Dirichlet series in Cn are defined and some relations between them and the coefficients and exponents of n-tuple Dirichlet series are obtained. 展开更多
关键词 multiple Dirichlet series lower order linear order
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Theoretical Explanation for Lower Order Harmonic Resonance Phenomenon of Three-Ring Gear Transmissions 被引量:2
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作者 杨建明 张策 +1 位作者 林忠钦 陈关龙 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第1期71-74,共4页
Dynamic investigations revealed that lower order harmonic resonance phenomenon exists in the three ring gear transmission. That is, when the input speed is close to 1/3, 1/6, 1/9,…, 1/3 n of the primary natural frequ... Dynamic investigations revealed that lower order harmonic resonance phenomenon exists in the three ring gear transmission. That is, when the input speed is close to 1/3, 1/6, 1/9,…, 1/3 n of the primary natural frequency of the transmission, the loads on the bearings and gears are especially high. This paper explained this phenomenon from the viewpoint of parametric resonance in terms of perturbation technique. A conclusion was drawn that the basic reason for this phenomenon is the primary resonance caused by forcing excitation and parametric resonance caused by parametric change. 展开更多
关键词 three ring gear transmission lower order resonance phenomenon natural frequency primary resonance parametric resonance
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THE GENERALIZED LOWER ORDER OF DIRICHLET SERIES 被引量:1
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作者 Qingyuan CHEN Yingying HUO 《Acta Mathematica Scientia》 SCIE CSCD 2020年第4期1141-1151,共11页
In this paper,we study the generalized lower order of entire functions defined by Dirichlet series.By constructing the Newton polygon based on Knopp-Kojima’s formula,we obtain a relation between the coefficients of t... In this paper,we study the generalized lower order of entire functions defined by Dirichlet series.By constructing the Newton polygon based on Knopp-Kojima’s formula,we obtain a relation between the coefficients of the Dirichlet series and its generalized lower order. 展开更多
关键词 Dirichlet series Knopp-Kojima method Newton polygon generalized lower order
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The Lower Order and Type of Solutions of Second Order Differential Equation
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作者 ZHANG Shao-hua WU Zhao-jun SUN Dao-chun 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期14-21,共8页
The main purpose of this paper is to study the lower order and type of second order differential equation w"(z)-A(z)w=0,where A(z)is a polynomial.In the case of A(z)=a_dz^d,the authors prove that the lower order ... The main purpose of this paper is to study the lower order and type of second order differential equation w"(z)-A(z)w=0,where A(z)is a polynomial.In the case of A(z)=a_dz^d,the authors prove that the lower order and the type of all non-trivial solutions w of w"(z)-A(z)w=0 are equal to(d+2)/2 and(2(|a_d|)^(1/2))/(d+2)respectively.In the case of A(z)=a_dz^d+a_(d-1)z^(d-1)+…a_1z+a_0,a_d>0,a_(d-1)>0,…,a_1≥0,a_0≥0,the authors prove that the lower order of all non-trivial solutions w of w"(z)-A(z)w=0 is(d+2)/2. 展开更多
关键词 TYPE order lower order differential equation
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Construction of Split-Plot Designs with General Minimum Lower Order Confounding
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作者 Kexin Li Beichen Han Zhenzhen Niu 《Open Journal of Applied Sciences》 CAS 2023年第3期261-274,共14页
Fractional factorial split-plot design has been widely used in many fields due to its advantage of saving experimental cost. The general minimum lower order confounding criterion is usually used as one of the attracti... Fractional factorial split-plot design has been widely used in many fields due to its advantage of saving experimental cost. The general minimum lower order confounding criterion is usually used as one of the attractive design criterion for selecting fractional factorial split-plot design. In this paper, we are interested in the theoretical construction methods of the optimal fractional factorial split-plot designs under the general minimum lower order confounding criterion. We present the theoretical construction methods of optimal fractional factorial split-plot designs under general minimum lower order confounding criterion under several conditions. 展开更多
关键词 Fractional Factorial Design General Minimum lower order Confounding Criterion Split-Plot Design
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DOA Estimation Based on Sparse Representation of the Fractional Lower Order Statistics in Impulsive Noise 被引量:8
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作者 Sen Li Rongxi He +1 位作者 Bin Lin Fei Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第4期860-868,共9页
This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive ... This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive noise as α-stable distribution, new methods which combine the sparse signal representation technique and fractional lower order statistics theory are proposed. In the new algorithms, the fractional lower order statistics vectors of the array output signal are sparsely represented on an overcomplete basis and the DOAs can be effectively estimated by searching the sparsest coefficients. To enhance the robustness performance of the proposed algorithms,the improved algorithms are advanced by eliminating the fractional lower order statistics of the noise from the fractional lower order statistics vector of the array output through a linear transformation. Simulation results have shown the effectiveness of the proposed methods for a wide range of highly impulsive environments. 展开更多
关键词 α-stable distribution direction of arrival(DOA) fractional lower-order statistics impulsive noise sparse representation
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New blind estimation method of evoked potentials based on minimum dispersion criterion and fractional lower order statistics
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作者 Daifeng Zha 《Journal of Biomedical Science and Engineering》 2008年第2期91-97,共7页
Evoked potentials (EPs) have been widely used to quantify neurological system properties. Tra-ditional EP analysis methods are developed under the condition that the background noises in EP are Gaussian distributed. A... Evoked potentials (EPs) have been widely used to quantify neurological system properties. Tra-ditional EP analysis methods are developed under the condition that the background noises in EP are Gaussian distributed. Alpha stable distribution, a generalization of Gaussian, is better for modeling impulsive noises than Gaussian distribution in biomedical signal proc-essing. Conventional blind separation and es-timation method of evoked potentials is based on second order statistics or high order Statis-tics. Conventional blind separation and estima-tion method of evoked potentials is based on second order statistics (SOS). In this paper, we propose a new algorithm based on minimum dispersion criterion and fractional lower order statistics. The simulation experiments show that the proposed new algorithm is more robust than the conventional algorithm. 展开更多
关键词 EVOKED POTENTIALS (EPs) Alpha stable distribution BLIND source separation Minimum dispersion (MD) FRACTIONAL lower order statistics (FLOS)
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Some Results on Entire Functions of Finite Lower Order 被引量:7
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作者 Wu Shengjian Department of Mathematics Peking University Beijing, 100871 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1994年第2期168-178,共11页
Let f(z) be an entire function of order λ and of finite lower order μ. If the zeros of f(z) accumulate in the vicinity of a finite number of rays, then (a) λ is finite; (b) for every arbitrary number k<... Let f(z) be an entire function of order λ and of finite lower order μ. If the zeros of f(z) accumulate in the vicinity of a finite number of rays, then (a) λ is finite; (b) for every arbitrary number k<sub>1</sub>】1, there exists k<sub>2</sub>】1 such that T(k<sub>1</sub>r, f)≤k<sub>2</sub>T(r, f) for all r≥r<sub>0</sub>. Applying the above results, we prove that if f(z) is extremal for Yang’s inequality p=g/2, then (c) every deficient value of f(z) is also its asymptotic value; (d) every asymptotic value of f(z) is also its deficient value; (e) λ=μ; (f) ∑a≠∞δ5(a, f)≤1-k(μ). 展开更多
关键词 Some Results on Entire Functions of Finite lower order
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A theory on constructing blocked two-level designs with general minimum lower order confounding 被引量:1
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作者 Yuna ZHAO Shengli ZHAO Min-Qian LIU 《Frontiers of Mathematics in China》 SCIE CSCD 2016年第1期207-235,共29页
Completely random allocation of the treatment combinations to the experimental units is appropriate only if the experimental units are homogeneous. Such homogeneity may not always be guaranteed when the size of the ex... Completely random allocation of the treatment combinations to the experimental units is appropriate only if the experimental units are homogeneous. Such homogeneity may not always be guaranteed when the size of the experiment is relatively large. Suitably partitioning inhomogeneous units into homogeneous groups, known as blocks, is a practical design strategy. How to partition the experimental units for a given design is an important issue. The blocked general minimum lower order confounding is a new criterion for selecting blocked designs. With the help of doubling theory and second order saturated design, we present a theory on constructing optimal blocked designs under the blocked general minimum lower order confounding criterion. 展开更多
关键词 Aliased effect-number pattern general minimum lower orderconfounding second order saturated design Yates order
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Lower Approximation Reduction in Ordered Information System with Fuzzy Decision 被引量:1
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作者 Xiaoyan Zhang Weihua Xu 《Applied Mathematics》 2011年第7期918-921,共4页
Attribute reduction is one of the most important problems in rough set theory. This paper introduces the concept of lower approximation reduction in ordered information systems with fuzzy decision. Moreover, the judgm... Attribute reduction is one of the most important problems in rough set theory. This paper introduces the concept of lower approximation reduction in ordered information systems with fuzzy decision. Moreover, the judgment theorem and discernable matrix are obtained, in which case an approach to attribute reduction in ordered information system with fuzzy decision is constructed. As an application of lower approximation reduction, some examples are applied to examine the validity of works obtained in our works.. 展开更多
关键词 Fuzzy DECISION lower APPROXIMATION REDUCTION orderED Information Systems ROUGH Set
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Direction finding of bistatic MIMO radar in strong impulse noise
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作者 CHEN Menghan GAO Hongyuan +2 位作者 DU Yanan CHENG Jianhua ZHANG Yuze 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期888-898,共11页
For bistatic multiple-input multiple-output(MIMO)radar,this paper presents a robust and direction finding method in strong impulse noise environment.By means of a new lower order covariance,the method is effective in ... For bistatic multiple-input multiple-output(MIMO)radar,this paper presents a robust and direction finding method in strong impulse noise environment.By means of a new lower order covariance,the method is effective in suppressing impulse noise and achieving superior direction finding performance using the maximum likelihood(ML)estimation method.A quantum equilibrium optimizer algorithm(QEOA)is devised to resolve the corresponding objective function for efficient and accurate direc-tion finding.The results of simulation reveal the capability of the presented method in success rate and root mean square error over existing direction-finding methods in different application situations,e.g.,locating coherent signal sources with very few snapshots in strong impulse noise.Other than that,the Cramér-Rao bound(CRB)under impulse noise environment has been drawn to test the capability of the presented method. 展开更多
关键词 bistatic multiple-input multiple-output(MIMO)radar impulse noise direction finding lower order covariance quan-tum equilibrium optimizer algorithm(QEOA) maximum likeli-hood estimation method Cramér-Rao bound(CRB)
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THIRD-ORDER NONLINEAR SINGULARLY PERTURBED BOUNDARY VALUE PROBLEM 被引量:1
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作者 WANG Guo-can(王国灿) +1 位作者 JIN Li(金丽) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第6期670-677,共8页
Third order singulary perturbed boundary value problem by means of differential inequality theories is studied. Based on the given results of second order nonlinear boundary value problem, the upper and lower solution... Third order singulary perturbed boundary value problem by means of differential inequality theories is studied. Based on the given results of second order nonlinear boundary value problem, the upper and lower solutions method of third order nonlinear boundary value problems by making use of Volterra type integral operator was established. Specific upper and lower solutions were constructed, and existence and asymptotic estimates of solutions under suitable conditions were obtained. The result shows that it seems to be new to apply these techniques to solving these kinds of third order singularly perturbed boundary value problem. An example is given to demonstrate the applications. 展开更多
关键词 third order boundary value problem upper and lower solutions Volterra type integral operator existence and asymptotic estimates
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Research on Outcrop Sequence Stratigraphy of Permian in Middle-Lower Yangtze Region
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作者 ZhangKexin HeWeihong 《Journal of China University of Geosciences》 SCIE CSCD 2002年第2期192-202,共11页
According to the latest International Chronostratigraphic Scheme (ICS, 2000), the Permian in the Middle Lower Yangtze region of South China can be divided into three series and nine stages relevant to the traditional... According to the latest International Chronostratigraphic Scheme (ICS, 2000), the Permian in the Middle Lower Yangtze region of South China can be divided into three series and nine stages relevant to the traditional six stages of South China. From Assellian to Changxingian of Permian, 44 Ma in age range, the strata are composed of 14 third order sequences, each of which is 3.14 Ma in average age range. There is one third order sequence of Zisongian, equivalent to middle and upper Chuanshan Formation or equal to Asselian and two thirds of Sakmarian. There are two third order sequences, corresponding to Liang shan Formation or Zhenjiang Formation and upper Chuanshan Formation, which are assigned to Longlingian, coinciding with Artinskian and one third of Sakmarian. In addition, three third order sequences, equal to Qixia Formation, are attributed to Chihsian, corresponding to Kubergandian and one third of Roadian. Four third order sequences, comprising Gufeng, Maokou, Yanqiao, Yinping and Wuxue formations, are assigned to Maokouan, equivalent to two thirds of Roadian, Wordian and Capitanian. Two third order sequences, equal to Longtan Formation or Wujiaping Formation, are included in Wuchiapingian. Other two third order sequences, corresponding to Changxing Formation or Dalong Formation, are assigned to Changhsingian. In brief, these above third order sequences can be incorporated into 4 sequences sets. 展开更多
关键词 systems tract third order sequence sea level changes PERMIAN Middle lower Yangtze region.
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Existence of Positive Solutions for A Fourth-order Boundary Value Problems with p-Laplacian Operators
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作者 WANG Wan-peng 《Chinese Quarterly Journal of Mathematics》 2018年第4期377-385,共9页
This paper investigates the existence of positive solutions for a fourth-order p-Laplacian nonlinear equation. We show that, under suitable conditions, there exists a positive number λ~*such that the above problem ha... This paper investigates the existence of positive solutions for a fourth-order p-Laplacian nonlinear equation. We show that, under suitable conditions, there exists a positive number λ~*such that the above problem has at least two positive solutions for 0 < λ < λ~* , at least one positive solution for λ = λ~* and no solution forλ > λ~* by using the upper and lower solutions method and fixed point theory. 展开更多
关键词 FOURTH-order P-LAPLACIAN POSITIVE SOLUTIONS UPPER and lower SOLUTIONS method Fixed point theory
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三水平逆耶茨序设计的低阶混杂性质
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作者 黄智赟 李智明 《应用概率统计》 CSCD 北大核心 2024年第3期452-462,共11页
在三水平正规设计中,低阶成分效应的混杂信息对选择最优设计至关重要.本文研究一类三水平逆耶茨序设计Dq(n),其中q为独立列个数,n为因子个数,得到设计Dq(n)在三种情况下低阶混杂信息的结果:(i)q<n<3q-1,n=2k,k∈N;(ii)q<n<3... 在三水平正规设计中,低阶成分效应的混杂信息对选择最优设计至关重要.本文研究一类三水平逆耶茨序设计Dq(n),其中q为独立列个数,n为因子个数,得到设计Dq(n)在三种情况下低阶混杂信息的结果:(i)q<n<3q-1,n=2k,k∈N;(ii)q<n<3q-1;n=2k+1;k∈N;(iii)3q-1≤n<(3q-1)/2.通过实例来演示上述结果. 展开更多
关键词 正规设计 逆耶茨序 别名成分数型 一般最小低阶混杂准则
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Existence of Solutions to the Higher Order Nonlinear Differential Equations
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作者 TANG Lin-shan JIANG Cheng-shun 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期1-10,共10页
This paper is concerned with the following n-th ordinary differential equation:{u~(n)(t)=f(t,u(t),u~(1)(t),···,u~(n-1) (t)),for t∈(0,1),u~(i) (0)=0,0 ≤i≤n3,au~(n-2)(0)du~(n-1)(0)=0,cu~(n-2)(1)... This paper is concerned with the following n-th ordinary differential equation:{u~(n)(t)=f(t,u(t),u~(1)(t),···,u~(n-1) (t)),for t∈(0,1),u~(i) (0)=0,0 ≤i≤n3,au~(n-2)(0)du~(n-1)(0)=0,cu~(n-2)(1)+du~(n-1)(1)=0,where a,c ∈ R,,≥,such that a~2 + b~2 >0 and c~2+d~2>0,n ≥ 2,f:[0,1] × R → R is a continuous function.Assume that f satisfies one-sided Nagumo condition,the existence theorems of solutions of the boundary value problem for the n-th-order nonlinear differential equations above are established by using Leray-Schauder degree theory,lower and upper solutions,a priori estimate technique. 展开更多
关键词 n-th order boundary value problems one-sided Nagumo condition lower and upper solutions a priori estimates Leray-Schauder degree
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极限下限分析的区域光滑径向点插值法
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作者 陈莘莘 董昊 李庆华 《力学季刊》 CAS CSCD 北大核心 2024年第3期697-705,共9页
极限分析的高效数值计算方法在结构设计和安全评定中具有非常重要的作用.为了更加有效地求解极限分析问题,将区域光滑径向点插值法与二阶锥规划相结合,提出了理想弹塑性结构极限下限分析的一种新方法.将问题域离散为简单的三角形背景单... 极限分析的高效数值计算方法在结构设计和安全评定中具有非常重要的作用.为了更加有效地求解极限分析问题,将区域光滑径向点插值法与二阶锥规划相结合,提出了理想弹塑性结构极限下限分析的一种新方法.将问题域离散为简单的三角形背景单元,每个单元进一步划分成若干个光滑域.为了将复杂的域积分转化为简单的边界积分,并且避免计算形函数的导数,采用广义梯度光滑技术对每个光滑域进行应变光滑处理.由于径向点插值法构造的形函数满足Kronecker delta性质,本质边界条件可以直接施加.依据下限定理,在满足以等效积分弱形式表达的自平衡应力场平衡条件的基础上,用二阶锥规划成功构建了极限分析下限法的计算模型,从而可方便地通过基于原始-对偶内点法的数学规划求解器MOSEK直接求解该问题.数值算例结果表明,本文所提方法有效地克服了维数障碍问题,具有较高的计算精度,并且计算结果对网格畸变十分不敏感. 展开更多
关键词 无网格法 区域光滑径向点插值法 极限下限分析 广义梯度光滑技术 二阶锥规划
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灾后应急配送中心选址问题的降阶回溯算法
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作者 胡开元 宁爱兵 +2 位作者 尹远翔 陈至伟 张惠珍 《物流科技》 2024年第16期1-5,共5页
近年来自然灾害频发,提高灾后应急物资的配送效率一直以来都是性命攸关的大事,因此文章基于灾后应急配送中心选址问题的精确算法进行研究。首先,建立该问题的数学模型并对该问题中的数学性质进行研究和证明;其次,在这些数学性质的基础上... 近年来自然灾害频发,提高灾后应急物资的配送效率一直以来都是性命攸关的大事,因此文章基于灾后应急配送中心选址问题的精确算法进行研究。首先,建立该问题的数学模型并对该问题中的数学性质进行研究和证明;其次,在这些数学性质的基础上,设计上下界子算法和降阶子算法,这些子算法能够有效减少解空间,提高算法的效率,使该算法能够更有效地处理规模更大的问题;再次,提出降阶回溯子算法,通过剪枝和局部降阶进一步缩小问题的搜索规模,并能得到最优解;最后,通过分析和解决一个案例来更清楚地说明算法的原理和操作步骤。 展开更多
关键词 应急配送中心选址问题 上下界算法 降阶回溯算法
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奖励-收集Steiner树问题的精确算法
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作者 曾宾 宁爱兵 +2 位作者 付振星 付馨懿 张惠珍 《系统管理学报》 CSSCI CSCD 北大核心 2024年第5期1242-1250,共9页
奖励-收集Steiner树问题是图的Steiner最小树问题的衍生,同时也是组合优化中的NP-hard问题。首先,提出该问题的数学性质并给出证明,利用数学性质能降低该问题的规模;其次,基于该问题的数学性质设计出上下界子算法、降阶子算法和回溯子算... 奖励-收集Steiner树问题是图的Steiner最小树问题的衍生,同时也是组合优化中的NP-hard问题。首先,提出该问题的数学性质并给出证明,利用数学性质能降低该问题的规模;其次,基于该问题的数学性质设计出上下界子算法、降阶子算法和回溯子算法,通过上下界子算法和降阶子算法可以降低该问题解空间的规模,从而缩短回溯子算法的搜索时间,进而降低求解该问题最优解的时间;最后,应用案例分析、算例分析以及算法分析与对比表明,所设计的算法不仅可以求出该问题的最优解,而且比没有考虑该问题数学性质的一般回溯算法的时间复杂度更低。 展开更多
关键词 奖励-收集Steiner树 上下界子算法 降阶子算法 回溯子算法
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