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Euler Product Expressions of Absolute Tensor Products of Dirichlet L-Functions
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作者 Hidenori Tanaka Shin-ya Koyama 《Advances in Pure Mathematics》 2024年第6期451-486,共36页
In this paper, we calculate the absolute tensor square of the Dirichlet L-functions and show that it is expressed as an Euler product over pairs of primes. The method is to construct an equation to link primes to a se... In this paper, we calculate the absolute tensor square of the Dirichlet L-functions and show that it is expressed as an Euler product over pairs of primes. The method is to construct an equation to link primes to a series which has the factors of the absolute tensor product of the Dirichlet L-functions. This study is a generalization of Akatsuka’s theorem on the Riemann zeta function, and gives a proof of Kurokawa’s prediction proposed in 1992. 展开更多
关键词 dirichlet l-function Absolute Tensor Product (Kurokawa Tensor Product) Euler Product
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一种利用远场数据恢复Dirichlet特征值的神经网络方案
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作者 徐照斌 孟品超 《长春理工大学学报(自然科学版)》 2024年第2期128-133,共6页
探讨了声场中利用远场数据重构具有Dirichlet边界条件的障碍物的特征值反问题,提出了一种基于数据驱动的神经网络方案。首先针对具有Dirichlet边界条件的障碍物建立内特征值问题和外散射问题的数学模型,然后构建一个具有序列对序列结构... 探讨了声场中利用远场数据重构具有Dirichlet边界条件的障碍物的特征值反问题,提出了一种基于数据驱动的神经网络方案。首先针对具有Dirichlet边界条件的障碍物建立内特征值问题和外散射问题的数学模型,然后构建一个具有序列对序列结构的多层前馈神经网络,该网络采用反向传播误差和自学习的方式更新网络中的超参数,最后在散射体信息未知的前提下,利用远场数据重构障碍物的Dirichlet特征值。数值实验表明该方法可以有效地重构障碍物的Dirichlet特征值。 展开更多
关键词 特征值反问题 dirichlet特征值 远场数据 数据驱动的神经网络
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Localisation Inverse Problem and Dirichlet-to-Neumann Operator for Absorbing Laplacian Transport
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作者 Ibrahim Baydoun 《Journal of Modern Physics》 2013年第6期772-779,共8页
We study Laplacian transport by the Dirichlet-to-Neumann formalism in isotropic media (γ = I). Our main results concern the solution of the localisation inverse problem of absorbing domains and its relative Dirichlet... We study Laplacian transport by the Dirichlet-to-Neumann formalism in isotropic media (γ = I). Our main results concern the solution of the localisation inverse problem of absorbing domains and its relative Dirichlet-to-Neumann operator . In this paper, we define explicitly operator , and we show that Green-Ostrogradski theorem is adopted to this type of problem in three dimensional case. 展开更多
关键词 Absorbing LAPLACIAN TRANSPORT dirichlet-to-Neumann Operators inverse Problem
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半平面中的Dirichlet边值逆问题 被引量:4
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作者 王明华 《四川师范大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第6期683-687,共5页
给出半平面中解析函数的一类Dirichlet边值逆问题的数学提法.依据半平面中解析函数的D irichlet边值问题和广义D irichlet边值问题,讨论了此边值逆问题的可解性.利用半平面中解析函数D irichlet边值问题的Schwarz公式,给出了该边值逆问... 给出半平面中解析函数的一类Dirichlet边值逆问题的数学提法.依据半平面中解析函数的D irichlet边值问题和广义D irichlet边值问题,讨论了此边值逆问题的可解性.利用半平面中解析函数D irichlet边值问题的Schwarz公式,给出了该边值逆问题的可解条件和解的表示式. 展开更多
关键词 dirichlet边值逆问题 dirichlet边值问题 Schwarz公式
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PROPORTION OF DISTINCT ZEROS OF A DIRICHLET L-SERIES
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作者 Xinhua QIN Xiaosheng WU 《Acta Mathematica Scientia》 SCIE CSCD 2022年第6期2367-2376,共10页
By studying the distribution of zeros of combinations of a Dirichlet L-function and its first-order derivative,we prove that every Dirichlet L-function has more than 66.7934%distinct zeros.
关键词 simple zeros distinct zeros dirichlet l-function
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Solution of 1D Poisson Equation with Neumann-Dirichlet and Dirichlet-Neumann Boundary Conditions, Using the Finite Difference Method
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作者 Serigne Bira Gueye Kharouna Talla Cheikh Mbow 《Journal of Electromagnetic Analysis and Applications》 2014年第10期309-318,共10页
An innovative, extremely fast and accurate method is presented for Neumann-Dirichlet and Dirichlet-Neumann boundary problems for the Poisson equation, and the diffusion and wave equation in quasi-stationary regime;usi... An innovative, extremely fast and accurate method is presented for Neumann-Dirichlet and Dirichlet-Neumann boundary problems for the Poisson equation, and the diffusion and wave equation in quasi-stationary regime;using the finite difference method, in one dimensional case. Two novels matrices are determined allowing a direct and exact formulation of the solution of the Poisson equation. Verification is also done considering an interesting potential problem and the sensibility is determined. This new method has an algorithm complexity of O(N), its truncation error goes like O(h2), and it is more precise and faster than the Thomas algorithm. 展开更多
关键词 1D POISSON Equation Finite Difference Method Neumann-dirichlet dirichlet-Neumann Boundary Problem TRIDIAGONAL Matrix inversion Thomas Algorithm
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Localisation Inverse Problem of Absorbing Laplacian Transport
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作者 Ibrahim Baydoun 《Journal of Modern Physics》 2013年第5期572-578,共7页
We study the localisation inverse problem corresponding to Laplacian transport of absorbing cell. Our main goal is to find sufficient Dirichelet-to-Neumann conditions insuring that this inverse problem is uniquely sol... We study the localisation inverse problem corresponding to Laplacian transport of absorbing cell. Our main goal is to find sufficient Dirichelet-to-Neumann conditions insuring that this inverse problem is uniquely soluble. In this paper, we show that the conformal mapping technique is adopted to this type of problem in the two dimensional case. 展开更多
关键词 LAPLACIAN TRANSPORT dirichlet-to-Neumann Operators inverse Problem CONFORMAL Mapping
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An Explicit Formula of the Dirichlet-to-Neumann Map for a Radial Potential in Dimension 3
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作者 Fagueye Ndiaye 《Journal of Applied Mathematics and Physics》 2022年第2期379-404,共26页
In this paper, we provide an explicit expression for the full Dirichlet-to-Neumann map corresponding to a radial potential for the Schr&#246;dinger equation in 3-dimensional. We numerically implement the coefficie... In this paper, we provide an explicit expression for the full Dirichlet-to-Neumann map corresponding to a radial potential for the Schr&#246;dinger equation in 3-dimensional. We numerically implement the coefficients of the explicit formulas. In this work, Lipschitz type stability is established near the edge of the domain with giving estimation constant. That is necessary for the reconstruction of the potential from Dirichlet-to-Neuman map. 展开更多
关键词 Calderón’s Problem Schrödinger Operator POTENTIAL inverse Potential Problem dirichlet-to-Neuman Map Numerical Simulations Lipschitz Stability
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Dirichlet-to-Neumann Map for a Hyperbolic Equation
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作者 Fagueye Ndiaye Mouhamadou Ngom Diaraf Seck 《Journal of Applied Mathematics and Physics》 2023年第8期2231-2251,共21页
In this paper, we provide an explicit expression for the full Dirichlet-to-Neumann map corresponding to a radial potential for a hyperbolic differential equation in 3-dimensional. We show that the Dirichlet-Neumann op... In this paper, we provide an explicit expression for the full Dirichlet-to-Neumann map corresponding to a radial potential for a hyperbolic differential equation in 3-dimensional. We show that the Dirichlet-Neumann operators corresponding to a potential radial have the same properties for hyperbolic differential equations as for elliptic differential equations. We numerically implement the coefficients of the explicit formulas. Moreover, a Lipschitz type stability is established near the edge of the domain by an estimation constant. That is necessary for the reconstruction of the potential from Dirichlet-to-Neumann map in the inverse problem for a hyperbolic differential equation. 展开更多
关键词 Hyperbolic Differential Equation Calderón’s Problem Schrödinger Operator POTENTIAL inverse Potential Problem dirichlet-to-Neumann Map Numerical Simulations Lipschitz Stability
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基于改进TF-IDF与BERT的领域情感词典构建方法 被引量:1
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作者 蒋昊达 赵春蕾 +1 位作者 陈瀚 王春东 《计算机科学》 CSCD 北大核心 2024年第S01期150-158,共9页
领域情感词典的构建是领域文本情感分析的基础。现有的领域情感词典构建方法存在所筛选候选情感词冗余度高、情感极性判断失准、领域依赖性强等问题。为了提高所筛选候选情感词的领域性和判断领域情感词极性的准确程度,提出了一种基于... 领域情感词典的构建是领域文本情感分析的基础。现有的领域情感词典构建方法存在所筛选候选情感词冗余度高、情感极性判断失准、领域依赖性强等问题。为了提高所筛选候选情感词的领域性和判断领域情感词极性的准确程度,提出了一种基于改进词频-逆文档频率(TF-IDF)与BERT的领域情感词典构建方法。该方法在筛选领域候选情感词阶段对TF-IDF算法进行改进,将隐含狄利克雷分布(LDA)算法与改进后的TF-IDF算法结合,进行领域性修正,提升了所筛选候选情感词的领域性;在候选情感词极性判断阶段,将情感倾向点互信息算法(SO-PMI)与BERT结合,利用领域情感词微调BERT分类模型,提高了判断领域候选情感词情感极性的准确程度。在不同领域的用户评论数据集上进行实验,结果表明,该方法可以提高所构建领域情感词典的质量,使用该方法构建的领域情感词典用于汽车领域和手机领域文本情感分析的F1值分别达到78.02%和88.35%。 展开更多
关键词 情感分析 领域情感词典 词频-逆文档频率 隐含狄利克雷分布 情感倾向点互信息算法 BERT模型
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On the 2k-th Power Mean of Inversion of L-functions with the Weight of the Gauss Sum 被引量:3
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作者 YuanYI WenPengZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2004年第1期175-180,共6页
The main purpose of this paper is to use the estimate for character sums and the method of trigonometric sums to study the 2k-th power mean of the inversion of Dirichlet L-functions with the weight of the Gauss sums, ... The main purpose of this paper is to use the estimate for character sums and the method of trigonometric sums to study the 2k-th power mean of the inversion of Dirichlet L-functions with the weight of the Gauss sums, and give a sharper asymptotic formula. 展开更多
关键词 dirichlet l-functions Gauss sums Mean value Asymptotic formula
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融合TF-IDF和LDA的中文FastText短文本分类方法 被引量:31
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作者 冯勇 屈渤浩 +2 位作者 徐红艳 王嵘冰 张永刚 《应用科学学报》 CAS CSCD 北大核心 2019年第3期378-388,共11页
FastText文本分类模型具有快速高效的优势,但直接将其用于中文短文本分类则存在精确率不高的问题.为此提出一种融合词频-逆文本频率(term frequency-inverse document frequency, TF-IDF)和隐含狄利克雷分布(latent Dirichlet allocatio... FastText文本分类模型具有快速高效的优势,但直接将其用于中文短文本分类则存在精确率不高的问题.为此提出一种融合词频-逆文本频率(term frequency-inverse document frequency, TF-IDF)和隐含狄利克雷分布(latent Dirichlet allocation, LDA)的中文FastText短文本分类方法.该方法在FastText文本分类模型的输入阶段对n元语法模型处理后的词典进行TF-IDF筛选,使用LDA模型进行语料库主题分析,依据所得结果对特征词典进行补充,从而在计算输入词序列向量均值时偏向高区分度的词条,使其更适用于中文短文本分类环境.对比实验结果可知,所提方法在中文短文本分类方面具有更高的精确率. 展开更多
关键词 中文短文本分类 FastText 词频-逆文本频率 词向量 隐含狄利克雷分布
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关于特征和与L-函数的混合均值
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作者 张小蹦 《黑龙江大学自然科学学报》 CAS 北大核心 2012年第1期56-58,64,共4页
考虑特征和的均值估计,张小蹦研究了不完整区间上特征和与Dirichlet L-函数倒数的均值估计。利用初等方法以及Igor E.Shparlinski的思想,改进了张小蹦结论的误差项。
关键词 不完整区间特征和 dirichlet L-函数的倒数 渐近公式
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基于单频数据重构散射障碍的新型线性采样方法
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作者 丁濛 《工程数学学报》 CSCD 北大核心 2020年第5期583-590,共8页
散射及反散射的数学理论与计算一直是应用数学领域中的重要课题,其成果在地质勘探、无损探测、医学成像等领域都具有广泛的应用.线性采样方法(LSM)是近年来反散射理论中一类非常流行的非迭代型重建算法,但是这种方式很难推广到如半空间... 散射及反散射的数学理论与计算一直是应用数学领域中的重要课题,其成果在地质勘探、无损探测、医学成像等领域都具有广泛的应用.线性采样方法(LSM)是近年来反散射理论中一类非常流行的非迭代型重建算法,但是这种方式很难推广到如半空间中障碍反散射等更为复杂的问题中.本文基于单频数据研究Dirichlet障碍反散射问题的数值重建算法.通过构造带有阻尼边界条件的辅助边值问题,提出了一类新型的线性采样方法,并在理论上严格证明了该方法在任意给定的波数下重构障碍形状及位置的有效性. 展开更多
关键词 反散射 dirichlet障碍 线性采样方法 单频数据
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基于TFIDF+LDA和Mini Batch K⁃means算法的在线课程推荐方法研究
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作者 严武军 王丽蓉 《现代计算机》 2023年第23期15-20,共6页
在线教育资源急剧增长让学习者难以抉择,研究在线课程分类推荐,能帮助学习者快速获取所需资源。首先将潜在狄利克雷分配算法融入词频-逆向文件频率算法对数据进行预处理,生成词向量矩阵;之后采用Mini Batch K-means算法训练聚类模型,并... 在线教育资源急剧增长让学习者难以抉择,研究在线课程分类推荐,能帮助学习者快速获取所需资源。首先将潜在狄利克雷分配算法融入词频-逆向文件频率算法对数据进行预处理,生成词向量矩阵;之后采用Mini Batch K-means算法训练聚类模型,并采用T分布随机邻域嵌入降维算法对训练结果进行可视化分析。实验采用从Pluralsight在线课程API获取8016条数据进行实验,实验结果表明融入潜在狄利克雷分配算法的词频-逆向文件频率算法效果更好。 展开更多
关键词 词频逆向文件频率 潜在狄利克雷分配 Mini Batch K-means 在线课程推荐
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基于LDA主题的改进TFIDF 95598工单智能分类研究 被引量:10
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作者 武光华 李洪宇 +2 位作者 刘二刚 柳长发 李倩 《微型电脑应用》 2020年第3期87-90,共4页
为了提高95595工单智能分类的准确率,提出了基于LDA(Latent Dirichlet Allocation)的改进TFIDF算法。先对文本提取特征词,然后采用K-means算法进行聚类处理。构建LDA模型,获得概率分布函数θ和φ,求取语义影响力SI(semantic influence,... 为了提高95595工单智能分类的准确率,提出了基于LDA(Latent Dirichlet Allocation)的改进TFIDF算法。先对文本提取特征词,然后采用K-means算法进行聚类处理。构建LDA模型,获得概率分布函数θ和φ,求取语义影响力SI(semantic influence,SI)作为特征词的权重,该改进算法记作SI-TFIDF(semantic influence-term frequency inverse document frequency,SI-TFIDF)。将SI-TFIDF算法与传统的TFIDF算法在sougou的数据库进行特征词提取,并采用K-means算进行聚类,对比结果显示,采用SI-TFIDF算法提取的特征词聚类效果优于TFIDF,验证了所提出方法的可靠性。在95598投诉工单上进行仿真实验,SI-TFIDF算法的投诉工单聚类准确率高于传统的TFIDF算法,验证了SI-TFIDF更适用于处理工单投诉的分类研究。 展开更多
关键词 95598 投诉工单 LATENT dirichlet allocation TERM FREQUENCY inverse document FREQUENCY
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Fermat小定理的推广及其应用
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作者 张敏 李金蒋 居腾霞 《江苏师范大学学报(自然科学版)》 CAS 2012年第4期1-5,共5页
利用映射的不动点以及不动点阶的思想将整数环Z上的Fermat小定理推广到一般集合S上,并运用该推广讨论了Dirichlet定理的一种特殊情形:只要给定正整数m≥3,那么算术数列1+lm(l=0,1,2,…)中一定存在无穷多个素数.
关键词 Fermat小定理 dirichlet定理 Mobius反演公式 分圆多项式 素数
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On the reconstruction of Dirichlet-to-Neumann map in inverse scattering problems with stability estimates 被引量:2
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作者 WANG HaiBing 1,2 & LIU JiJun 1 1 Department of Mathematics,Southeast University,Nanjing 210096,China 2 School of Mathematics and Computational Science,Hunan University of Science and Technology,Xiangtan 411201,China 《Science China Mathematics》 SCIE 2010年第8期2069-2084,共16页
Consider the determination of Dirichlet-to-Neumann(D-to-N) map from the far-field pattern in inverse scattering problems,which is the key step in some recently developed inversion schemes such as probe method.Essentia... Consider the determination of Dirichlet-to-Neumann(D-to-N) map from the far-field pattern in inverse scattering problems,which is the key step in some recently developed inversion schemes such as probe method.Essentially,this problem is related to the reconstruction of the scattered wave from its far-field data.We firstly prove the well-known uniqueness result of the D-to-N map from the far-field pattern using a new scheme based on the mixed reciprocity principle.The advantage of this new proof scheme is that it provides an efficient algorithm for computing the D-to-N map,avoiding the numerical differentiation for the scattered wave.Then combining with the classical potential theory,a simple and feasible regularizing reconstruction scheme for the D-to-N map is proposed.Finally the stability estimate for the reconstruction with noisy input data is rigorously analyzed. 展开更多
关键词 inversE scattering dirichlet-to-Neumann map REGULARIZATION mixed RECIPROCITY PRINCIPLE stability
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Some Notes on Identities for Dirichlet L-functions
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作者 Rong MA Yu Long ZHANG Melchior GRTZMANN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2014年第5期747-754,共8页
Let q ≥ 3 be an integer, and χ be a Dirichlet character modulo q, L(s, χ) denote the Dirichlet L-function corresponding to χ. In this paper, we show some early information on the mean value of the Dirichlet L-fu... Let q ≥ 3 be an integer, and χ be a Dirichlet character modulo q, L(s, χ) denote the Dirichlet L-function corresponding to χ. In this paper, we show some early information on the mean value of the Dirichlet L-functions and give some new identities forwhere a = 2, 3, or 4. Then we give general identities for the case that the integer a divides q - 1. Keywords Dirichlet L-functions, Dedekind sum, trigonometric formula, MSbius inversion formula 展开更多
关键词 dirichlet l-functions Dedekind sum trigonometric formula M¨obius inversion formula
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Several Expressions of Dirichlet L-function at Positive Integers
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作者 Yuan HE 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2019年第9期1549-1562,共14页
In this paper, by making use of Abel’s theorem on power series, the reflection formula and the function equation for Hurwitz zeta function, we establish several expressions of Dirichlet Lfunction at positive integers... In this paper, by making use of Abel’s theorem on power series, the reflection formula and the function equation for Hurwitz zeta function, we establish several expressions of Dirichlet Lfunction at positive integers by means of some finite sums of different types. Some special cases as well as immediate consequences of the results presented here are also considered. 展开更多
关键词 dirichlet l-function trigonometric SUMS GAUSS SUMS BERNOULLI polynomials combinatorial IDENTITIES
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