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Asymptotic Solution to Scattering Problem on a Set of Small Particles and Application to Creating the Materials with a Peculiar Refractive Index
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作者 Mykhaylo I. Andriychuk 《Journal of Applied Mathematics and Physics》 2020年第3期375-391,共17页
The asymptotic solution to the scattering problem on a set of small particles, supplemented into homogeneous material, is used for modeling the materials with the desired refractive index. The consideration concerns t... The asymptotic solution to the scattering problem on a set of small particles, supplemented into homogeneous material, is used for modeling the materials with the desired refractive index. The consideration concerns the case of acoustic scalar scattering and the solution to initial scattering problem is built using an asymptotic approach. The closed form solution is reduced for the scattering problem. This is significant advantage of approach because there is no need to solve the respective system of boundary integral equations. High accuracy of solving the scattering problem is achieved by choosing the optimal parameters of the domain with small particles. The approach allows obtaining an explicit formula for the refractive index of the resulting inhomogeneous material. The numerical calculations show the possibility to get the specific values of refractive index including its negative values. 展开更多
关键词 SET of Small Particles SCATTERING problem ASYMPTOTIC Solution PECULIAR Refractive index Computational Modeling
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基于Hash算法的DNA序列k-mer index问题的数学建模 被引量:3
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作者 郭方舟 华阳 +1 位作者 董修伟 蔡志丹 《长春理工大学学报(自然科学版)》 2015年第5期116-119,共4页
针对查找DNA序列的相似序列问题,给出了建立索引和查找索引的数学模型,基于Hash算法,建立了依赖于k值大小的顺序索引模型和散列索引模型,特别对较大k值选用了DJBHash函数,有效的避免了Hash冲突问题。最后在硬件平台CPU为2.6GHz、内存为8... 针对查找DNA序列的相似序列问题,给出了建立索引和查找索引的数学模型,基于Hash算法,建立了依赖于k值大小的顺序索引模型和散列索引模型,特别对较大k值选用了DJBHash函数,有效的避免了Hash冲突问题。最后在硬件平台CPU为2.6GHz、内存为8G、操作系统为64位Windows 7的条件下,对100万条长度为100的DNA序列进行了测试,给出了不同k值下建立和查询索引的用时和占用内存情况,有效的解决了DNA序列的k-mer index问题。 展开更多
关键词 HASH算法 索引问题 数学模型 复杂度分析
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软件实验DNA k-mer index四字链表字典树检索算法
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作者 王辉 于立君 +2 位作者 张旭 高菁 魏智红 《实验室科学》 2018年第1期81-84,共4页
针对软件实验中常涉及到的DNA碱基序列k-mer 问题,提出一种基于四字链表字典树的快速检索算法。根据不同的k值建立深度为k的四字字典树,最大程度地避免字符串中重复公共前缀而造成的空间浪费,压缩内存消耗,降低空间复杂度;以叶子节点作... 针对软件实验中常涉及到的DNA碱基序列k-mer 问题,提出一种基于四字链表字典树的快速检索算法。根据不同的k值建立深度为k的四字字典树,最大程度地避免字符串中重复公共前缀而造成的空间浪费,压缩内存消耗,降低空间复杂度;以叶子节点作为k-mer 结束标志建立索引查询链表,并输出k-mer 的所有序列号与位置号,最终完成DNA序列k-mer 问题的建立索引与快速查找任务。实验表明,该算法具有很高的查找效率,且可以减少查询时间,能够高效解决DNA序列的k-mer index问题。 展开更多
关键词 k-mer问题 四字字典树 索引链表
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ON HILBERT BOUNDARY VALUE PROBLEMS WITH RADICAL 被引量:4
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作者 路见可 《Acta Mathematica Scientia》 SCIE CSCD 2005年第4期755-760,共6页
The Hilbert boundary value problem Re{λ(t) p√ψ+(t)} = c(t), t∈L of normal type with Holder continuous coefficients is discussed, where L is the unit circle |t| = 1,p ≥2 is any definite integer,ψ^+(t)... The Hilbert boundary value problem Re{λ(t) p√ψ+(t)} = c(t), t∈L of normal type with Holder continuous coefficients is discussed, where L is the unit circle |t| = 1,p ≥2 is any definite integer,ψ^+(t) is the boundary value of the unknown function ψ(z) holomorphic in |z| 〈 1 with single-valued continuous p√ψ+(t) on L. 展开更多
关键词 Hilbert boundary value problem index class h0 Plemelj formula normalized canonical function
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ON SOLUTION OF A KIND OF RIEMANN BOUNDARY VALUE PROBLEM WITH SQUARE ROOTS 被引量:19
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作者 路见可 《Acta Mathematica Scientia》 SCIE CSCD 2002年第2期145-149,共5页
Solution of the Riemann boundary value problem with square roots (1.1) for analytic functions proposed in [1] is reconsidered, which was solved under certain assumptions on the branch points appeared. Here the work is... Solution of the Riemann boundary value problem with square roots (1.1) for analytic functions proposed in [1] is reconsidered, which was solved under certain assumptions on the branch points appeared. Here the work is continued without these assumptions and the problem is solved in the general case. 展开更多
关键词 Riemann boundary value problem branch points index order at infinity sectionally holomorphic functions
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MULTIPLE POSITIVE SOLUTIONS FOR SUPERLINEAR SECOND ORDER SINGULAR BOUNDARY VALUE PROBLEMS WITH DERIVATIVE DEPENDENCE 被引量:2
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作者 闫宝强 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期851-864,共14页
The existence of at least two positive solutions is presented for the singular second-order boundary value problem{1/p(t)( p(t)x′(t))′+Φ(t)f(t,x(t),p(t)x′(t))=0,0〈t〈1, limt→0 p(t)x′(t)=... The existence of at least two positive solutions is presented for the singular second-order boundary value problem{1/p(t)( p(t)x′(t))′+Φ(t)f(t,x(t),p(t)x′(t))=0,0〈t〈1, limt→0 p(t)x′(t)=0,x(1)=0by using the fixed point index, where f may be singular at x = 0 and px ′= 0. 展开更多
关键词 Boundary value problems SINGULARITY fixed point index
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Existence of Multiple Positive Solutions for Singular Impulsive Boundary Value Problems in Banach Space 被引量:3
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作者 徐西安 《Northeastern Mathematical Journal》 CSCD 2004年第3期317-330,共14页
In this paper, we first obtain some new results about the existence of multiple positive solutions for singular impulsive boundary value problems, and then to illustrate our main results we studied the existence of mu... In this paper, we first obtain some new results about the existence of multiple positive solutions for singular impulsive boundary value problems, and then to illustrate our main results we studied the existence of multiple positive solutions for an infinite system of scalar equations. 展开更多
关键词 Singular problem fixed point index multiple positive solution
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The Relationship of Psychological Symptoms among Mothers of Children in Different Body Mass Index Categories
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作者 Gulsen Meral Aysegul Uslu Asli Bostanci 《Open Journal of Pediatrics》 2016年第2期149-157,共9页
We tried to emphasize the importance of psychological status analysis of the mothers of children, who have abnormal Body Mass Index (BMI), when treating these children. Materials and methods: Our study enrolled mother... We tried to emphasize the importance of psychological status analysis of the mothers of children, who have abnormal Body Mass Index (BMI), when treating these children. Materials and methods: Our study enrolled mothers of 150 children in normal, high and low BMI categories who were admitted to Kagithane State Hospital. The inclusion criteria required that these children had no chronic disease, developmental defect, and diagnosed psychological or physical disease impairing the reliability of the interview. Symptom Check List (SCL-90-R) and Beck Depression Scale (BDS) were used on all mothers of these children. In this study, BDS values of high BMI children’s mothers were significantly higher than those of normal BMI children’s mothers and BDS values of mothers of low BMI children were found to be higher than those of mothers of normal BMI children. The SCL-90-R results between mothers of high and normal BMI, high and low BMI, normal and low BMI children were statistically significant. We observed the effect of the psychological state of the family on childhood eating habits and the higher incidence of childhood feeding problems in families with psychopathology. Currently family therapy is indicated according to guidelines in solving eating disorders in children. This approach may also be useful for children with abnormal BMI. 展开更多
关键词 FAMILY CHILDREN Body Mass index Feeding problems DEPRESSION
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Positive Solutions for Fractional Differential Equations with Multi-Point Boundary Value Problems 被引量:1
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作者 Lina Zhou Weihua Jiang 《Journal of Applied Mathematics and Physics》 2014年第5期108-114,共7页
In this paper, a fractional multi-point boundary value problem is considered. By using the fixed point index theory and Krein-Rutman theorem, some results on existence are obtained.
关键词 Caputo FRACTIONAL DERIVATIVE FRACTIONAL INTEGRAL BOUNDARY VALUE problem Fixed Point index Theory
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TWO POSITIVE SOLUTIONS TO THREE-POINT SINGULAR BOUNDARY VALUE PROBLEMS 被引量:3
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作者 李宇华 梁占平 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期29-38,共10页
In this article, we consider the existence of two positive solutions to nonlinear second order three-point singular boundary value problem: -u′′(t) = λf(t, u(t)) for all t ∈ (0, 1) subjecting to u(0) = ... In this article, we consider the existence of two positive solutions to nonlinear second order three-point singular boundary value problem: -u′′(t) = λf(t, u(t)) for all t ∈ (0, 1) subjecting to u(0) = 0 and αu(η) = u(1), where η ∈ (0, 1), α ∈ [0, 1), and λ is a positive parameter. The nonlinear term f(t, u) is nonnegative, and may be singular at t = 0, t = 1, and u = 0. By the fixed point index theory and approximation method, we establish that there exists λ* ∈ (0, +∞], such that the above problem has at least two positive solutions for any λ ∈ (0, λ*) under certain conditions on the nonlinear term f. 展开更多
关键词 Three-point singular boundary value problem positive solutions fixed point index
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The Solution of A Compound Periodic Boundary Problem
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作者 ZHUJun-ming DUJin-yuan 《Wuhan University Journal of Natural Sciences》 CAS 2005年第2期344-346,共3页
We have studied the compound periodic boundary problem in the upper halfplane above the real axis. Under proper conditions, we obtain a periodic and sectionallyholo-morphic function in the upper half plane. In additio... We have studied the compound periodic boundary problem in the upper halfplane above the real axis. Under proper conditions, we obtain a periodic and sectionallyholo-morphic function in the upper half plane. In addition, we have also solved the compoundboundary problem with discontinuities of the first kind of the coefficients in the Hilbertcondition. 展开更多
关键词 Riemann boundary problem Hilbert boundary problem compound boundaryproblem periodic boundary problem index
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Non-Homogeneous Riemann Boundary Value Problem with Radicals 被引量:6
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作者 Lu Jian-ke School of Mathematics and Statistics,Wuhan University,Wuhan 430072, Hubei,China 《Wuhan University Journal of Natural Sciences》 EI CAS 2002年第4期379-382,共4页
The solution of the non-homogeneous Riemann boundary value problem with radicals (1. 2) together with its condition of solvability is obtained for arbitrary positive integersp andq, which generalizes the results for t... The solution of the non-homogeneous Riemann boundary value problem with radicals (1. 2) together with its condition of solvability is obtained for arbitrary positive integersp andq, which generalizes the results for the casep=q=2. 展开更多
关键词 Riemann boundary value problem branch points of radicals index order at infinity sectionally holomorphic functions
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A Generalized Riemann Boundary Value Problem 被引量:10
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作者 LIU Hua LU Jian 《Wuhan University Journal of Natural Sciences》 CAS 2000年第2期147-149,共3页
The generalized Riemann boundary value problem for analytic functions is considered, where the unknown function may have branch points of the second order. Under certain assumptions, its general solution as well as th... The generalized Riemann boundary value problem for analytic functions is considered, where the unknown function may have branch points of the second order. Under certain assumptions, its general solution as well as the condition of solvability is obtained when the solution is required to be of finite order at infinity. 展开更多
关键词 Riemann boundary value problem sectionally holomorphic function order at infinily index
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EXTENSION OF SOLUTIONS TO RIEMANN BOUNDARY VALUE PROBLEMS AND ITS APPLICATION 被引量:2
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作者 路见可 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期694-702,共9页
In this paper, solutions of Riemann boundary value problems with nodes are extended to the case where they may have singularties of high order at the nodes. Moreover, further extension is discussed when the free term ... In this paper, solutions of Riemann boundary value problems with nodes are extended to the case where they may have singularties of high order at the nodes. Moreover, further extension is discussed when the free term of the problem involved also possesses singularities at the nodes. As an application, certain singular integral equation is discussed. 展开更多
关键词 Riemann boundary value problem class KN index and canonical function in class KN almost bounded almost of order k characteristic singular integral equation
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Reconsideration on Homogeneous Quadratic Riemann Boundary Value Problem 被引量:2
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作者 LuJian-ke 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第1期1-5,共5页
The homogeneous quadratic riemann boundary value problem (1) with H?lder continuous coefficients for the normal case was considered by the author in 1997. But the solutions obtained there are incomplete. Here its gene... The homogeneous quadratic riemann boundary value problem (1) with H?lder continuous coefficients for the normal case was considered by the author in 1997. But the solutions obtained there are incomplete. Here its general method of solution is obtained. Key words homogeneous quadratic Riemann boundary value problem - ordinary and special nodes - index - sectionally holomorphic function CLC number O 175.5 Foundation item: Supported by the National Natural Science Foundation of China (19871064)Biography: Lu Jian-ke (1922-), male, Professor, research direction: complex analysis and its applications. 展开更多
关键词 homogeneous quadratic Riemann boundary value problem ordinary and special nodes index sectionally holomorphic function
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Existence and Multiplicity of Positive Solutions for a Singular Third-Order Three-Point Boundary Value Problem with a Parameter
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作者 Xingfang Feng Hanying Feng 《Journal of Applied Mathematics and Physics》 2022年第4期1146-1157,共12页
In this paper, we investigate the existence of positive solutions for a singular third-order three-point boundary value problem with a parameter. By using fixed point index theory, some existence, multiplicity and non... In this paper, we investigate the existence of positive solutions for a singular third-order three-point boundary value problem with a parameter. By using fixed point index theory, some existence, multiplicity and nonexistence results for positive solutions are derived in terms of different values of λ. 展开更多
关键词 Three-Point Boundary Value problem Fixed Point index Positive Solution EXISTENCE MULTIPLICITY
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Optimal index shooting policy for layered missile defense system 被引量:1
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作者 LI Longyue FAN Chengli +2 位作者 XING Qinghua XU Hailong ZHAO Huizhen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期118-129,共12页
In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting op... In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting optimization is how to choose the next BM which needs to be shot according to the previous engagements and results,thus maximizing the expected return of BMs killed or minimizing the cost of BMs penetration.Motivated by this,this study aims to determine an optimal shooting policy for a two-layer missile defense(TLMD)system.This paper considers a scenario in which the TLMD system wishes to shoot at a collection of BMs one at a time,and to maximize the return obtained from BMs killed before the system demise.To provide a policy analysis tool,this paper develops a general model for shooting decision-making,the shooting engagements can be described as a discounted reward Markov decision process.The index shooting policy is a strategy that can effectively balance the shooting returns and the risk that the defense mission fails,and the goal is to maximize the return obtained from BMs killed before the system demise.The numerical results show that the index policy is better than a range of competitors,especially the mean returns and the mean killing BM number. 展开更多
关键词 Gittins index shooting policy layered missile defense multi-armed bandits problem Markov decision process
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Solving Intuitionistic Fuzzy Linear Programming Problem 被引量:3
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作者 Arpita Kabiraj Prasun Kumar Nayak Swapan Raha 《International Journal of Intelligence Science》 2019年第1期44-58,共15页
Intuitionistic Fuzzy Set (IFS) can be used as a general tool for modeling problems of decision making under uncertainty where, the degree of rejection is defined simultaneously with the degree of acceptance of a piece... Intuitionistic Fuzzy Set (IFS) can be used as a general tool for modeling problems of decision making under uncertainty where, the degree of rejection is defined simultaneously with the degree of acceptance of a piece of information in such a way that these degrees are not complement to each other. Accordingly, an attempt is made to solve intuitionistic fuzzy linear programming problems using a technique based on an earlier technique proposed by Zimmermann to solve fuzzy linear programming problem. Our proposed technique does not require the existing ranking of intuitionistic fuzzy numbers. This method is also different from the existing weight assignment method or the Angelov’s method. A comparative study is undertaken and interesting results have been presented. 展开更多
关键词 Intuitionistic FUZZY Set Intuitionistic index Intuitionistic FUZZY NUMBER Intuitionistic FUZZY LINEAR PROGRAMMING problem FUZZY LINEAR PROGRAMMING problem
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指数有界双连续n阶α次积分C半群与高阶抽象Cauchy问题研究
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作者 葛国菊 《佳木斯大学学报(自然科学版)》 CAS 2024年第4期173-176,92,共5页
算子半群理论在求解Cauchy问题等领域具有很大的应用价值,并且其在泛函分析理论等各方面的研究中同样有着重要意义。此次研究在Banach空间上,基于泛函分析、算子半群理论对柯西问题进行探讨。并基于n阶α次积分C半群的生成定理,对指数... 算子半群理论在求解Cauchy问题等领域具有很大的应用价值,并且其在泛函分析理论等各方面的研究中同样有着重要意义。此次研究在Banach空间上,基于泛函分析、算子半群理论对柯西问题进行探讨。并基于n阶α次积分C半群的生成定理,对指数有界双连续n阶α次积分C半群的生成定理与其Laplace逆变换表达式进行推算。由结果可知,L∞范数误差在分数阶n为1.47时达到最低值,为0.04,这表明其与实际值极为接近。在T=0.2,0.5两种时刻下,中精确解和正则解的变化趋势基本一致,并且二者的误差在x∈0.1,0.9区间内接近于0。研究有效验证了指数有界双连续n阶α次积分C半群解决高阶抽象Cauchy问题具有适用性与可靠性。 展开更多
关键词 高阶抽象Cauchy问题 适定性 指数有界 双连续 n阶α次积分C半群
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基于生成对抗网络的强对流临近预报方法及其在中国东部地区的应用评估
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作者 曾康 闵锦忠 +1 位作者 庄潇然 康志明 《大气科学》 CSCD 北大核心 2024年第6期2316-2328,共13页
为了缓解深度学习雷达回波外推预报中普遍存在的模糊问题,发展了一种有机融合PhyDNet方法和频域匹配生成对抗网络的雷达回波外推预报方法(PhyDNetSGAN),能够预测江苏及其上游地区未来3 h的雷达组合反射率因子,通过对比PhyDNetSGAN、PhyD... 为了缓解深度学习雷达回波外推预报中普遍存在的模糊问题,发展了一种有机融合PhyDNet方法和频域匹配生成对抗网络的雷达回波外推预报方法(PhyDNetSGAN),能够预测江苏及其上游地区未来3 h的雷达组合反射率因子,通过对比PhyDNetSGAN、PhyDNet(未使用生成对抗网络)、PhyDNetGAN和Sprog(改进的光流法)验证了新方法在强对流天气临近预报中的适用性。结果表明:(1)与光流法Sprog相比,深度学习方法能更好地体现强回波的非线性发展演变过程。(2)增加生成对抗网络的PhyDNetGAN和PhyDNetSGAN较其他两组试验能够得到更精细且符合预报员主观认知的雷达回波外推结果,缓解模糊问题。(3)新提出的PhyDNetSGAN不仅能够改善预报精细度,还能更好地捕获强回波的形态、位置和中心强度,从而获得更优的预报技巧,延长有效预报时长。(4)新提出的综合TS评分、Bias评分和FID评分的综合评分指标较TS评分能够更好地反应与预报员主观体验相一致的临近预报检验效果。 展开更多
关键词 生成对抗网络 雷达回波外推 模糊问题 综合评分指标
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