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s-Conditionally Permutable Subgroups and p-Nilpotency of Finite Groups
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作者 刘熠 秦亚 《Journal of Southwest Jiaotong University(English Edition)》 2010年第2期177-181,共5页
A subgroup H of G is called s-conditionally permutable in G if for every Sylow subgroup T of G, there exists an element x ∈ G such that HTK = T^KH. In this paper, we investigate further the influence of s-conditional... A subgroup H of G is called s-conditionally permutable in G if for every Sylow subgroup T of G, there exists an element x ∈ G such that HTK = T^KH. In this paper, we investigate further the influence of s-conditionally permutability of some 2-maximal subgroups of the Sylow subgroup of G, on the structure of finite groups. New criteria for a group G being p-nilpotent are obtained. 展开更多
关键词 s-conditionally permutable subgroup 2-Maximal subgroup p-Nilpotent group
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On the Julia Sets of Permutable Transcendental Entire Functions
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作者 朱玲妹 杨德贵 王小灵 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期270-273,共4页
Let f and g be two permutable transcendental entire functions. In this paper, we first prove that J(fg)=J(f n g m) for any positive integers n and m . Then we prove that the function h(p(z))+az ∈/ B , where h(z) is... Let f and g be two permutable transcendental entire functions. In this paper, we first prove that J(fg)=J(f n g m) for any positive integers n and m . Then we prove that the function h(p(z))+az ∈/ B , where h(z) is any transcendental entire function with h′(z)=0 having infinitely many solutions, p(z) is a polynomial with deg p ≥2 and a(≠0) ∈ C . 展开更多
关键词 singular value Fatou component permutable transcendental entire function
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ON SYMMETRIC EXTENDED MS-ALGEBRAS WHOSE CONGRUENCES ARE PERMUTABLE 被引量:1
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作者 罗从文 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1113-1122,共10页
Algebras whose congruences are permutable were investigated by a number of authors in the literature. In this paper, we study the symmetric extended MS-algebras whose congruences are permutable. Some results obtained ... Algebras whose congruences are permutable were investigated by a number of authors in the literature. In this paper, we study the symmetric extended MS-algebras whose congruences are permutable. Some results obtained by Jie Fang on symmetric extended De Morgan algebras are generalized. 展开更多
关键词 extended Ockham algebra symmetric extended MS-algebra congruence permutable
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Congruence Permutable Kleene-Stone Algebras
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作者 LUO Congwen WANG Gaoxia 《Wuhan University Journal of Natural Sciences》 CAS 2010年第2期99-102,共4页
A Kleene-Stone algebra is a bounded distributive lattice with two unary operations that make it a Kleene and a Stone algebra.In this paper,we study the properties of the prime ideals in a Kleene-Stone algebra and char... A Kleene-Stone algebra is a bounded distributive lattice with two unary operations that make it a Kleene and a Stone algebra.In this paper,we study the properties of the prime ideals in a Kleene-Stone algebra and characterize the class of Kleene-Stone algebras that are congruence permutable by means of the dual space of a Kleene-Stone algebra and then show that a finite Kleene-Stone algebra is congruence permutable if and only if it is isomorphic to a direct product of finitely many simple algebras. 展开更多
关键词 Kleene-Stone algebra Kleene-Stone space congruence permutable
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The Lebesgue Measure of the Julia Sets of Permutable Transcendental Entire Functions
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作者 Cunji Yang Shaomin Wang 《Advances in Pure Mathematics》 2022年第9期526-534,共9页
In 1958, Baker posed the question that if f and g are two permutable transcendental entire functions, must their Julia sets be the same? In order to study this problem of permutable transcendental entire functions, by... In 1958, Baker posed the question that if f and g are two permutable transcendental entire functions, must their Julia sets be the same? In order to study this problem of permutable transcendental entire functions, by the properties of permutable transcendental entire functions, we prove that if f and g are permutable transcendental entire functions, then mes (J(f)) = mes (J(g)). Moreover, we give some results about the zero measure of the Julia sets of the permutable transcendental entire functions family. 展开更多
关键词 Transcendental Entire Function permutable Functions Random Dynamics Julia Set Lebesgue Measure
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An Iterated Greedy Algorithm with Memory and Learning Mechanisms for the Distributed Permutation Flow Shop Scheduling Problem
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作者 Binhui Wang Hongfeng Wang 《Computers, Materials & Continua》 SCIE EI 2025年第1期371-388,共18页
The distributed permutation flow shop scheduling problem(DPFSP)has received increasing attention in recent years.The iterated greedy algorithm(IGA)serves as a powerful optimizer for addressing such a problem because o... The distributed permutation flow shop scheduling problem(DPFSP)has received increasing attention in recent years.The iterated greedy algorithm(IGA)serves as a powerful optimizer for addressing such a problem because of its straightforward,single-solution evolution framework.However,a potential draw-back of IGA is the lack of utilization of historical information,which could lead to an imbalance between exploration and exploitation,especially in large-scale DPFSPs.As a consequence,this paper develops an IGA with memory and learning mechanisms(MLIGA)to efficiently solve the DPFSP targeted at the mini-malmakespan.InMLIGA,we incorporate a memory mechanism to make a more informed selection of the initial solution at each stage of the search,by extending,reconstructing,and reinforcing the information from previous solutions.In addition,we design a twolayer cooperative reinforcement learning approach to intelligently determine the key parameters of IGA and the operations of the memory mechanism.Meanwhile,to ensure that the experience generated by each perturbation operator is fully learned and to reduce the prior parameters of MLIGA,a probability curve-based acceptance criterion is proposed by combining a cube root function with custom rules.At last,a discrete adaptive learning rate is employed to enhance the stability of the memory and learningmechanisms.Complete ablation experiments are utilized to verify the effectiveness of the memory mechanism,and the results show that this mechanism is capable of improving the performance of IGA to a large extent.Furthermore,through comparative experiments involving MLIGA and five state-of-the-art algorithms on 720 benchmarks,we have discovered that MLI-GA demonstrates significant potential for solving large-scale DPFSPs.This indicates that MLIGA is well-suited for real-world distributed flow shop scheduling. 展开更多
关键词 Distributed permutation flow shop scheduling MAKESPAN iterated greedy algorithm memory mechanism cooperative reinforcement learning
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Sign-Balanced Pattern-Avoiding Permutation Classes
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作者 Junyao PAN Pengfei GUO 《Journal of Mathematical Research with Applications》 2025年第4期427-436,共10页
A set of permutations is called sign-balanced if the set contains the same number of even permutations as odd permutations.Let S_(n)(σ_(1),σ_(2),...,σ_(r))denote the set of permutations in the symmetric group S_(n)... A set of permutations is called sign-balanced if the set contains the same number of even permutations as odd permutations.Let S_(n)(σ_(1),σ_(2),...,σ_(r))denote the set of permutations in the symmetric group S_(n)which avoid patternsσ_(1),σ_(2),...,σ_(r).The aim of this paper is to investigate when,for certain patternsσ_(1),σ_(2),...,σ_(r),S_(n)(σ_(1),σ_(2),...,σ_(r))is sign-balanced for every integer n>1.We prove that for any{σ_(1),σ_(2),...,σ_(r)}?S_3,if{σ_(1),σ_(2),...,σ_(r)}is sign-balanced except for{132,213,231,312},then S_(n)(σ_(1),σ_(2),...,σ_(r))is sign-balanced for every integer n>1.In addition,we give some results in the case of avoiding some patterns of length 4. 展开更多
关键词 permutATION sign-balanced symmetric group avoid patterns
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A Note on a Class of Permutation Quadrinomials of F_(q^(2))
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作者 QIN Xiaoer GUO Xiaonan +1 位作者 QIU Yinuo YAN Li 《Wuhan University Journal of Natural Sciences》 2025年第3期231-234,共4页
Constructing permutation polynomials is a hot topic in finite fields,and permutation polynomials have many applications in dif‐ferent areas.In this paper,by using monomials on the cosets of a subgroup to characterize... Constructing permutation polynomials is a hot topic in finite fields,and permutation polynomials have many applications in dif‐ferent areas.In this paper,by using monomials on the cosets of a subgroup to characterize the permutational property of rational functions onμq+1,we construct a class of permutation quadrinomials with the form f_(r,a,b,c,s,t,u)(x)=x^(r)(1+ax^(s(q-1))+bx^(t(q-1))+cxu(q-1))of F_(q^(2)). 展开更多
关键词 permutation quadrinomials MONOMIALS finite fields
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Efficient implementation of quantum permutation algorithm using a polar SrO molecule in pendular states
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作者 Jie-Ru Hu Zuo-Yuan Zhang Jin-Ming Liu 《Communications in Theoretical Physics》 2025年第2期39-51,共13页
Quantum algorithms offer more enhanced computational efficiency in comparison to their classical counterparts when solving specific tasks.In this study,we implement the quantum permutation algorithm utilizing a polar ... Quantum algorithms offer more enhanced computational efficiency in comparison to their classical counterparts when solving specific tasks.In this study,we implement the quantum permutation algorithm utilizing a polar molecule within an external electric field.The selection of the molecular qutrit involves the utilization of field-dressed states generated through the pendular modes of SrO.Through the application of multi-target optimal control theory,we strategically design microwave pulses to execute logical operations,including Fourier transform,oracle U_(f)operation,and inverse Fourier transform within a three-level molecular qutrit structure.The observed high fidelity of our outcomes is intricately linked to the concept of the quantum speed limit,which quantifies the maximum speed of quantum state manipulation.Subsequently,we design the optimized pulse sequence to successfully simulate the quantum permutation algorithm on a single SrO molecule,achieving remarkable fidelity.Consequently,a quantum circuit comprising a single qutrit suffices to determine permutation parity with just a single function evaluation.Therefore,our results indicate that the optimal control theory can be well applied to the quantum computation of polar molecular systems. 展开更多
关键词 polar molecule optimal control quantum permutation algorithm pendular states
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A Secure Audio Encryption Method Using Tent-Controlled Permutation and Logistic Map-Based Key Generation
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作者 Ibtisam A.Taqi Sarab M.Hameed 《Computers, Materials & Continua》 2025年第10期1653-1674,共22页
The exponential growth of audio data shared over the internet and communication channels has raised significant concerns about the security and privacy of transmitted information.Due to high processing requirements,tr... The exponential growth of audio data shared over the internet and communication channels has raised significant concerns about the security and privacy of transmitted information.Due to high processing requirements,traditional encryption algorithms demand considerable computational effort for real-time audio encryption.To address these challenges,this paper presents a permutation for secure audio encryption using a combination of Tent and 1D logistic maps.The audio data is first shuffled using Tent map for the random permutation.The high random secret key with a length equal to the size of the audio data is then generated using a 1D logistic map.Finally,the Exclusive OR(XOR)operation is applied between the generated key and the shuffled audio to yield the cipher audio.The experimental results prove that the proposed method surpassed the other techniques by encrypting two types of audio files,as mono and stereo audio files with large sizes up to 122 MB,different sample rates 22,050,44,100,48,000,and 96,000 for WAV and 44,100 sample rates for MP3 of size 11 MB.The results show high Mean Square Error(MSE),low Signal-to-Noise Ratio(SNR),spectral distortion,100%Number of Sample Change Rate(NSCR),high Percent Residual Deviation(PRD),low Correlation Coefficient(CC),large key space 2^(616),high sensitivity to a slight change in the secret key and that it can counter several attacks,namely brute force attack,statistical attack,differential attack,and noise attack. 展开更多
关键词 Wave protection 1D logistic map Tent map random permutation key generation
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Layer-2 transferable belief model:Manage uncertainty on random permutation sets
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作者 Qian-Li Zhou Yong Deng 《Journal of Electronic Science and Technology》 2025年第2期52-64,共13页
In this paper,the transferable belief model established on power sets is extended to the permutation event space(PES)and is referred to as the layer-2 transferable belief model.Our goal is to provide a comprehensive a... In this paper,the transferable belief model established on power sets is extended to the permutation event space(PES)and is referred to as the layer-2 transferable belief model.Our goal is to provide a comprehensive approach for handling and modeling uncertainty,capable of representing both quantitative and qualitative information.First,the motivation for proposing the layer-2 transferable belief model and its information processing principles are explored from the perspective of weak propensity.Then,based on these principles,the corresponding information processing methods for the credal and pignistic levels are developed.Finally,the advantages of this model are validated through a classifier that leverages attribute fusion to enhance performance and decision-making accuracy. 展开更多
关键词 Evidence theory Information processing Information fusion Layer-2 belief structure Random permutation set
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基于扩散先验的脑部MRI超分辨率重建
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作者 熊承义 曹雨轩 高志荣 《中南民族大学学报(自然科学版)》 2026年第2期202-211,共10页
现有基于Transformer的MRI超分辨率方法虽具有良好的全局建模能力,但忽略了深度先验约束建模的重要性.为此,提出了一种基于扩散先验的脑部MRI超分辨率方法,利用潜在扩散模型生成的先验来引导Transformer进行超分辨率重建,以提升MRI细节... 现有基于Transformer的MRI超分辨率方法虽具有良好的全局建模能力,但忽略了深度先验约束建模的重要性.为此,提出了一种基于扩散先验的脑部MRI超分辨率方法,利用潜在扩散模型生成的先验来引导Transformer进行超分辨率重建,以提升MRI细节重建能力.具体而言,采用两阶段协同训练策略:第一阶段通过真实图像潜编码构建内容先验;第二阶段引入扩散模型重构先验,并联合优化去噪与重建过程,实现无监督条件下的图像超分辨率.此外,采用深度可分离卷积与置换自注意力机制,实现编码器的高效建模与感受野扩展.在IXI多模态MRI数据集上的4倍超分辨率实验表明:所提出方法在提升重建图像主客观质量与重建效率方面优于已有方法 . 展开更多
关键词 MRI超分辨率 扩散先验 置换自注意力 深度可分离卷积
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最优和渐近最优码本的新构造
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作者 高有 谢明月 王刚 《中国民航大学学报》 2026年第1期86-90,共5页
码本是一类具有较低相关性的信号集,满足Welch界或Levenshtein界的码本(又称信号集)主要用于码分多址(CDMA,code-division multiple-access)系统中不同用户信号的区分,也可用于压缩感知、编码理论和量子计算。本文提供了两类关于Levensh... 码本是一类具有较低相关性的信号集,满足Welch界或Levenshtein界的码本(又称信号集)主要用于码分多址(CDMA,code-division multiple-access)系统中不同用户信号的区分,也可用于压缩感知、编码理论和量子计算。本文提供了两类关于Levenshtein界的最优和渐近最优码本的新构造。首先,利用设计理论对象网和Hadamard矩阵构造了一类新的关于Levenshtein界的最优码本;其次,利用有限域上的置换函数构造了一类关于Levenshtein界的渐近最优码本。参数对比表明,这两类码本的构造参数和方法均为新成果。 展开更多
关键词 最优码本 渐近最优码本 Levenshtein界 设计理论对象网 置换函数 有限域
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两个一维总体分布相等性的permutation检验 被引量:4
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作者 黄群 林洁梅 赵佳因 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2012年第6期929-932,共4页
检验两个一维总体分布的相等性,采用理论证明和数值模拟的方法,在Prastgaard提出的Kolmogorov-Smirnov统计量T1及相应的permutation统计量T 1基础上,提出了基于K-S统计量的新统计量T2及相应的permutation统计量T 2,研究了在一维的情形... 检验两个一维总体分布的相等性,采用理论证明和数值模拟的方法,在Prastgaard提出的Kolmogorov-Smirnov统计量T1及相应的permutation统计量T 1基础上,提出了基于K-S统计量的新统计量T2及相应的permutation统计量T 2,研究了在一维的情形下T2与T 2的分布,并进行了数值模拟.结果表明:新统计量在原假设下有相同的极限分布,数值模拟结果优于原统计量.该方法对检验两总体分布的相等性有一定的参考价值. 展开更多
关键词 permutation方法 K-S统计量 permutation统计量 假设检验 统计推断 经验分布函数 极限分布 数值模拟
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Permutation Test在假设检验中的应用 被引量:38
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作者 荀鹏程 赵杨 +3 位作者 易洪刚 柏建岭 于浩 陈峰 《数理统计与管理》 CSSCI 北大核心 2006年第5期616-621,共6页
本文介绍了一种实用的、基于大量计算的统计推断方法———Permutation test。该法根据所研究的问题构造检验统计量,并利用手头样本,按排列组合的原理导出检验统计量的理论抽样分布;若难以导出确切的理论分布,则采用抽样模拟的方法估计... 本文介绍了一种实用的、基于大量计算的统计推断方法———Permutation test。该法根据所研究的问题构造检验统计量,并利用手头样本,按排列组合的原理导出检验统计量的理论抽样分布;若难以导出确切的理论分布,则采用抽样模拟的方法估计其近似分布,然后求出从该分布中获得手头样本及更极端样本的概率(P值),并界定此概率值,作出推论。本方法属分布自由检验,适用于总体分布未知的小样本资料,以及某些难以用常规方法分析的资料之假设检验问题。本文就“Permutation”的含义,“Permutation tes”t的特点,“统计量的构造”,“模拟次数的选择”,应用进展等问题展开探讨。 展开更多
关键词 排列(组合)检验 确切概率 假设检验 分布自由
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REVERSIBLE LOGIC GATE NETWORK CASCADE BASED ON PERMUTATION GROUP 被引量:1
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作者 管致锦 秦小麟 戴华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期219-223,共5页
The cascade of reversible logic gate network with n inputs and n outputs forms a group isomorphic to the symmetric group S2^n. Characteristics of a number of gates from the set of all generalized Toffoli gates are stu... The cascade of reversible logic gate network with n inputs and n outputs forms a group isomorphic to the symmetric group S2^n. Characteristics of a number of gates from the set of all generalized Toffoli gates are studied. Any permutation Sn is proved to be generated by a n-cycle 9 and a permutation τ= (ij,ik) together. It shows that any neighboring 2-cycle permutation can be generated by at most two NOT gates without ancilla bit. Based on the above theory, a cascade algorithm for reversible logic gate networks is proposed. A reversible example of logic gate network cascade is given to show the correctness of the algorithm. 展开更多
关键词 logic gates cascade connection permutation group
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Bootstrap和Permutation方法在样本率多重比较中的应用 被引量:3
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作者 钱俊 陈平雁 《中国医院统计》 2008年第1期43-45,共3页
目的介绍Bootstrap和Permutation方法在样本率多重比较中的应用。方法调用SAS中的MULTTEST过程,编写程序实现样本率的两两比较和与控制组比较,并通过实例说明效果。结果运用Bootstrap和Permutation方法能较好解决样本率的多重比较问题... 目的介绍Bootstrap和Permutation方法在样本率多重比较中的应用。方法调用SAS中的MULTTEST过程,编写程序实现样本率的两两比较和与控制组比较,并通过实例说明效果。结果运用Bootstrap和Permutation方法能较好解决样本率的多重比较问题。结论使用Bootstrap和Permutation方法的SAS程序,简单明了,结果准确,使用方便。 展开更多
关键词 BOOTSTRAP permutATION 样本率 多重比较
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基于ICEEMDAN和小波包阈值的滚动轴承故障特征分析
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作者 李鑫 石维喜 +3 位作者 蔡景 左洪福 周恒康 羊玢 《振动.测试与诊断》 北大核心 2026年第1期154-162,222,共10页
为了解决滚动轴承故障诊断过程中由于环境噪声干扰所导致的故障分类准确性较低的问题,提出一种基于改进型完全自适应噪声集合经验模态分解(improved complete ensemble empirical mode decomposition with adaptive noise,简称ICEEMDAN... 为了解决滚动轴承故障诊断过程中由于环境噪声干扰所导致的故障分类准确性较低的问题,提出一种基于改进型完全自适应噪声集合经验模态分解(improved complete ensemble empirical mode decomposition with adaptive noise,简称ICEEMDAN)与小波包阈值去噪相结合的多阶段处理的轴承故障诊断方法。首先,对滚动轴承的原始振动信号应用ICEEMDAN方法将其分解为不同分量;其次,基于分解结果构建相关系数-多尺度排列熵(multi-scale permutation entropy,简称MPE)筛选准则以划分高噪、低噪分量;然后,利用小波包阈值抑制高噪分量中的背景噪声,并与低噪分量进行重构;最后,对重构信号实施包络解调,提取出蕴含关键故障信息的特征信号,并建立故障特征能量图,实现对轴承故障类型的识别。为了验证所提出方法的有效性,分别采用滚动轴承外圈故障仿真数据、凯斯西储大学深沟球轴承实验台的故障数据和某型航空发动机三支点轴承试验平台的试验数据开展试验验证。试验结果表明,所提方法能够在复杂工况下准确识别滚动轴承的故障模式,对滚动轴承的智能运维具有重要的理论意义和工程实用价值。 展开更多
关键词 滚动轴承 小波包阈值 多尺度排列熵 包络谱 故障能量
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基于多种机器学习模型的沉积物质量评估研究——以太湖为例
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作者 钱姝羽 王品雅 +2 位作者 赵政 吴文斌 江和龙 《环境科学学报》 北大核心 2026年第1期488-498,共11页
本研究旨在将湖泊沉积物现有评估方法与机器学习在数据驱动、识别非线性关系方面的优势融合,开发新型的湖泊沉积物质量评估方法.基于2000—2022年太湖沉积物中重金属和氮磷等营养盐及相关元素的历史实验监测数据,以梯度提升机(GB)、支... 本研究旨在将湖泊沉积物现有评估方法与机器学习在数据驱动、识别非线性关系方面的优势融合,开发新型的湖泊沉积物质量评估方法.基于2000—2022年太湖沉积物中重金属和氮磷等营养盐及相关元素的历史实验监测数据,以梯度提升机(GB)、支持向量机(SVM)和随机森林(RF)3种机器学习算法为核心,构建了不同的太湖沉积物质量等级分类方案.模型性能评估采用精确率(Precision)、召回率(Recall)、F1值(F1 Score)和综合准确率(Accuracy)4项指标,对不同方案下的模型表现进行系统比较.结果显示,各方案的综合准确率均在84.98%以上,最佳评估方案为SVM结合输入方案4(Precision=0.892,Recall=0.901,F1=0.896,Accuracy=90.14%),并提出营养盐与重金属优化权重配比(0.4∶0.6).验证结果显示,在2000—2021年太湖不同区域的22条验证数据中,预测与真实分类在81.8%的时间点完全一致,其余结果多呈相邻等级偏差,等级1、6、7因样本量不足预测性能略低.为揭示各变量贡献,采用置换重要性(Permutation Importance)方法进行排序,结果表明,镉(Cd)、总氮(TN)、总磷(TP)是影响太湖沉积物质量的主导因素.本研究不仅为太湖沉积物动态监测提供了科学依据,还为未来太湖沉积物污染治理与评估方法的发展提供了技术路径参考. 展开更多
关键词 沉积物质量评估 机器学习 置换重要性 湖泊
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基于置换多项式簇的五类置换码构造及其参数分析
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作者 叶娜 夏永波 《数学杂志》 2026年第1期20-30,共11页
本文研究了基于有限域上的置换多项式构造置换码的问题.利用有限域上形如f(x)=αx^(m)+βx(其中m为正整数)的置换多项式簇,构造了五类置换码,并借助求解有限域上代数方程的一些方法,确定了这五类置换码的参数,包括码长、码字数量和极小... 本文研究了基于有限域上的置换多项式构造置换码的问题.利用有限域上形如f(x)=αx^(m)+βx(其中m为正整数)的置换多项式簇,构造了五类置换码,并借助求解有限域上代数方程的一些方法,确定了这五类置换码的参数,包括码长、码字数量和极小汉明距离,所得结果丰富了置换码的构造理论. 展开更多
关键词 置换多项式 置换码 极小汉明距离 码字数量 有限域
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