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The Influence of Second Maximal Subgroups on the Structure of Group Class J_(pr)
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作者 Lin YANG Wei LIU +1 位作者 Shuqin DONG Hongwei BAO 《Journal of Mathematical Research with Applications》 2025年第5期629-636,共8页
In this paper,we introduce the set of maximal subgroups with non-trivial core and their corresponding second maximal subgroups.A correlation characterization of the group class J_(pr)is presented by establishing the r... In this paper,we introduce the set of maximal subgroups with non-trivial core and their corresponding second maximal subgroups.A correlation characterization of the group class J_(pr)is presented by establishing the relationship between the core and the second maximal subgroups in these classifications. 展开更多
关键词 maximal subgroups second maximal subgroups group class J_(pr)
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Attributes reduct and decision rules optimization based on maximal tolerance classification in incomplete information systems with fuzzy decisions 被引量:1
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作者 Fang Yang Yanyong Guan +1 位作者 Shujin Li Lei Du 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期995-999,共5页
A new approach to knowledge acquisition in incomplete information system with fuzzy decisions is proposed. In such incomplete information system, the universe of discourse is classified by the maximal tolerance classe... A new approach to knowledge acquisition in incomplete information system with fuzzy decisions is proposed. In such incomplete information system, the universe of discourse is classified by the maximal tolerance classes, and fuzzy approximations are defined based on them. Three types of relative reducts of maximal tolerance classes are then proposed, and three types of fuzzy decision rules based on the proposed attribute description are defined. The judgment theorems and approximation discernibility functions with respect to them are presented to compute the relative reduct by using Boolean reasoning techniques, from which we can derive optimal fuzzy decision rules from the systems. At last, three types of relative reducts of the system and their computing methods are given. 展开更多
关键词 rough sets information systems maximal tolerance class attribute reduct decision rules.
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Boundeness of a Class of Maximal Operators on H^p Spaces on Compact Lie Groups
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作者 江寅生 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第4期1-9,共9页
In this paper we discuss the weak type(IP,I)boundedness of a class of maximal operators T and themaximal strong,mean boundedness of a family of the operators {T on the atomic IP spaces on compaet Lie groups.Also,we ob... In this paper we discuss the weak type(IP,I)boundedness of a class of maximal operators T and themaximal strong,mean boundedness of a family of the operators {T on the atomic IP spaces on compaet Lie groups.Also,we obtain the correspoding convergent rosults. 展开更多
关键词 compact Lie group IP spaces boundedness of a class of maximal operators
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Finite p-groups all of whose maximal abelian subgroups are soft
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作者 QU HaiPeng 《Science China Mathematics》 SCIE 2010年第11期3037-3040,共4页
A subgroup A of a p-group G is said to be soft in G if CG(A)=A and|NG(A)/A|=p.In this paper we determined finite p-groups all of whose maximal abelian subgroups are soft;see Theorem A and Proposition 2.4.
关键词 soft subgroup p-group of maximal class
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Maximal operators of pseudo-differential operators with rough symbols
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作者 Ramla Benhamoud ZHU Xiang-rong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期174-180,共7页
Consider a pseudo-differential operator T_(a)f(x)=∫_(R^(n))e^(ix,ζ)a(x,ζ)f(ζ)dζwhere the symbol a is in the rough Hormander class L^(∞)S_(ρ)^(m)with m∈R andρ∈[0,1].In this note,when 1≤p≤2,if n(ρ-1)/p and ... Consider a pseudo-differential operator T_(a)f(x)=∫_(R^(n))e^(ix,ζ)a(x,ζ)f(ζ)dζwhere the symbol a is in the rough Hormander class L^(∞)S_(ρ)^(m)with m∈R andρ∈[0,1].In this note,when 1≤p≤2,if n(ρ-1)/p and a∈L^(∞)S_(ρ)^(m),then for any f∈S(R^(n))and x∈R^(n),we prove that M(T_(a)f)(x)≤C(M(|f|^(p))(x))^(1/p) where M is the Hardy-Littlewood maximal operator.Our theorem improves the known results and the bound on m is sharp,in the sense that n(ρ-1)/p can not be replaced by a larger constant. 展开更多
关键词 pseudo-differential operator rough Hormander class H-L maximal operator
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MAXIMAL ELEMENTS AND EQUILIBRIUM OF ABSTRACT ECONOMY
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作者 刘心歌 蔡海涛 《应用数学和力学》 CSCD 北大核心 2001年第10期1105-1109,共5页
economy and qualitative game in which the constraint or preference correspondences are Q θ-majorized are obtained in locally convex topological vector spaces.
关键词 Qθ-类 Qθ-控制 最大元 抽象经济 经济均衡 拓扑向量空间
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MAXIMAL ELEMENTS AND EQUILIBRIUM OF ABSTRACT ECONOMY
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作者 LIU Xin-ge(刘心歌) +1 位作者 CAI Hai-tao(蔡海涛) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1225-1230,共6页
An existence theorem of maximal elements for a new type of preference correspondences which are Q(0)-majorized is given. Then some existence theorems of equilibrium for abstract economy and qualitative game in which t... An existence theorem of maximal elements for a new type of preference correspondences which are Q(0)-majorized is given. Then some existence theorems of equilibrium for abstract economy and qualitative game in which the constraint or preference correspondences are Q(0)-majorized are obtained in locally convex topological vector spaces. 展开更多
关键词 Q(0)-class Q(0)-majorized maximal element EQUILIBRIUM abstract economy
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基于强化类级匹配网络的齿轮箱跨域故障诊断
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作者 饶朗 邓艾东 +3 位作者 邓敏强 吴一凡 夏卫平 胡沁怡 《动力工程学报》 北大核心 2026年第1期148-156,共9页
为解决风电机组齿轮箱无监督域适应故障诊断领域存在的分类器决策边界附近样本误分类的问题,提出了一种强化类级匹配网络(RCMN)。该网络在最大化分类器差异的基础上,一方面通过引入基于伪标签的多步训练类级匹配机制,解决决策边界附近... 为解决风电机组齿轮箱无监督域适应故障诊断领域存在的分类器决策边界附近样本误分类的问题,提出了一种强化类级匹配网络(RCMN)。该网络在最大化分类器差异的基础上,一方面通过引入基于伪标签的多步训练类级匹配机制,解决决策边界附近样本误分类的问题;另一方面引入自适应对比学习损失函数,解决原有损失函数鲁棒性较差、对参数敏感的缺点。最后,在变转速和变负载2个案例下进行了模型验证。结果表明:在2个案例(共计12个迁移学习任务)中,RCMN的故障诊断准确率均高于最大均值差异、深度相关对齐网络、深度对抗领域适配网络和最大化分类器差异;所提RCMN在解决因分类器决策边界附近样本误分类导致的故障诊断准确率较低的问题上具有一定的有效性和优越性。 展开更多
关键词 故障诊断 无监督 类级匹配 最大化分类器差异 变工况
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On the Wielandt Subgroup in a p-Group of Maximal Class
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作者 Xiaohong ZHANG Xiuyun GUO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2012年第1期83-90,共8页
The Wielandt subgroup of a group G, denoted by w(G), is the intersection of the normalizers of all subnormal subgroups of G. In this paper, the authors show that for a p-group of maximal class G, either wi(G) = ζ... The Wielandt subgroup of a group G, denoted by w(G), is the intersection of the normalizers of all subnormal subgroups of G. In this paper, the authors show that for a p-group of maximal class G, either wi(G) = ζi(G) for all integer i or wi(G) = ζi+1(G) for every integer i, and w(G/K) = ζ(G/K) for every normal subgroup g in G with K ≠ 1. Meanwhile, a necessary and sufficient condition for a regular p-group of maximal class satisfying w(G) = ζ2(G) is given. Finally, the authors prove that the power automorphism group PAut(G) is an elementary abelian p-group if G is a non-abelian p- group with elementary ζ(G) ∩ζ1(G). 展开更多
关键词 p-groups of maximal class Wielandt subgroup Wielandt series Uppercentral series
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ANOTHER CHARACTERIZATIONS OF MUCKENHOUPT A_p CLASS 被引量:3
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作者 王定怀 周疆 陈文艺 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1761-1774,共14页
This manuscript addresses Muckenhoupt Ap weight theory in connection to Mor- rey and BMO spaces. It is proved that a; belongs to Muckenhoupt Ap class, if and only if Hardy-Littlewood maximal function M is bounded from... This manuscript addresses Muckenhoupt Ap weight theory in connection to Mor- rey and BMO spaces. It is proved that a; belongs to Muckenhoupt Ap class, if and only if Hardy-Littlewood maximal function M is bounded from weighted Lebesgue spaces LP(w) to weighted Morrey spaces Mpq(ω) for 1 〈 q 〈 p 〈 ∞. As a corollary, if M is (weak) bounded on Mpq(ω), then ω∈Ap. The Ap condition also characterizes the boundedness of the Riesz transform Rj and convolution operators Tε on weighted Morrey spaces. Finally, we show that ω∈Ap if and only if ω∈BMOp' (ω) for 1 ≤ p 〈 ∞ and 1/p + 1/p' = 1. 展开更多
关键词 CHARACTERIZATION Hardy-Littlewood maximal function Muckenhoupt Ap class weighted Morrey spaces weighted BMO space
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Finite p-Groups all of Whose Maximal Subgroups Either are Metacyclic or Have a Derived Subgroup of Order ≤ p 被引量:1
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作者 Lihua ZHANG Yanming XIA Qinhai ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2015年第1期11-30,共20页
The groups as mentioned in the title are classified up to isomorphism. This is an answer to a question proposed by Berkovich and Janko.
关键词 Finite p-groups Nonmetacyclic p-groups Minimal nonabelian p-groups maximal subgroups
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p-Capitulation over Number Fields with p-Class Rank Two 被引量:2
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作者 Daniel C. Mayer 《Journal of Applied Mathematics and Physics》 2016年第7期1280-1293,共14页
Theoretical foundations of a new algorithm for determining the p-capitulation type ù(K) of a number field K with p-class rank ?=2 are presented. Since ù(K) alone is insufficient for identifying the seco... Theoretical foundations of a new algorithm for determining the p-capitulation type ù(K) of a number field K with p-class rank ?=2 are presented. Since ù(K) alone is insufficient for identifying the second p-class group  G=Gal(F<sub>p</sub><sup>2</sup>K∣K) of K, complementary techniques are deve- loped for finding the nilpotency class and coclass of . An implementation of the complete algorithm in the computational algebra system Magma is employed for calculating the Artin pattern  AP(K)=(τ (K),ù(K)) of all 34631 real quadratic fields K=Q(√d) with discriminants  0d<10<sup>8</sup> and 3-class group of type (3, 3). The results admit extensive statistics of the second 3-class groups G=Gal(F<sub>3</sub><sup>2</sup>K∣K) and the 3-class field tower groups G=Gal(F<sub>3</sub><sup>∞</sup>K∣K). 展开更多
关键词 Hilbert p-class Field Tower maximal Unramified Pro-p Extension p-Capitulation of class Groups Real Quadratic Fields (3 3)
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Finite p-groups with abelian maximal subgroups generated by two elements
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作者 Zhixiu LI Haipeng QU 《Frontiers of Mathematics in China》 CSCD 2024年第1期1-12,共12页
Assume that G is a finite non-abelian p-group.If G has an abelian maximal subgroup whose number of Generators is at least n,then G is called an M_(n)-group.For p=2,M_(2)-groups have been classified.For odd prime p,thi... Assume that G is a finite non-abelian p-group.If G has an abelian maximal subgroup whose number of Generators is at least n,then G is called an M_(n)-group.For p=2,M_(2)-groups have been classified.For odd prime p,this paper provides the isomorphism classification of M_(2)-groups,thereby achieving a complete classification of M_(2)-groups. 展开更多
关键词 Finite p-group regular p-group abelian maximal subgroupnumber of Generators
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Successive Approximation of p-Class Towers
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作者 Daniel C. Mayer 《Advances in Pure Mathematics》 2017年第12期660-685,共26页
Let F be a number field and p be a prime. In the successive approximation theorem, we prove that, for each integer n ≥ 1, finitely many candidates for the Galois group of the nth stage of the p-class tower over F are... Let F be a number field and p be a prime. In the successive approximation theorem, we prove that, for each integer n ≥ 1, finitely many candidates for the Galois group of the nth stage of the p-class tower over F are determined by abelian type invariants of p-class groups C1pE of unramified extensions E/F with degree [E : F] = pn-1. Illustrated by the most extensive numerical results available currently, the transfer kernels (TE, F) of the p-class extensions TE, F : C1pF → C1pE from F to unramified cyclic degree-p extensions E/F are shown to be capable of narrowing down the number of contestants significantly. By determining the isomorphism type of the maximal subgroups S G of all 3-groups G with coclass cc(G) = 1, and establishing a general theorem on the connection between the p-class towers of a number field F and of an unramified abelian p-extension E/F, we are able to provide a theoretical proof of the realization of certain 3-groups S with maximal class by 3-tower groups of dihedral fields E with degree 6, which could not be realized up to now. 展开更多
关键词 p-class TOWERS Galois GROUPS Second p-class GROUPS Abelian Type Invariants of p-class GROUPS p-Transfer Kernel Types Artin Limit Pattern Quadratic FIELDS Unramified Cyclic Extensions of Degree p Dihedral FIELDS of Degree 2p Finite p-groups maximal Nilpotency class maximal Subgroups Polycyclic Pc-Presentations Commutator Calculus Central Series
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p-群上的作用与p-超可解性
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作者 白鹏飞 王俊新 曹建基 《山东大学学报(理学版)》 北大核心 2025年第5期13-19,共7页
设有限群A作用在有限p-群P上,其中|P|>p^(e)≥p^(3),e是某个固定的正整数,证明了若P中的每个pe阶非循环且非极大类子群皆是O^(p)(A)-不变的,则O^(p)(A^(■)_(p-1))在P上的作用是平凡的(即C_(p)(O^(p)(A^(■)_(p-1)))=P),其中■_(p-1... 设有限群A作用在有限p-群P上,其中|P|>p^(e)≥p^(3),e是某个固定的正整数,证明了若P中的每个pe阶非循环且非极大类子群皆是O^(p)(A)-不变的,则O^(p)(A^(■)_(p-1))在P上的作用是平凡的(即C_(p)(O^(p)(A^(■)_(p-1)))=P),其中■_(p-1)是由所有方次数整除p-1的交换群组成的群系,■是A的■剩余。给出了有限群是p-超可解的若干充分条件。 展开更多
关键词 非循环且非极大类p-群 P-超可解 S-半置换 ■-置换
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FINITE GROUPS WITH AT MOST TWO SAME ORDER CLASSES OF MAXIMAL SUBGROUPS
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作者 施武杰 《Chinese Science Bulletin》 SCIE EI CAS 1987年第19期1367-,共1页
S. Adnan has proved the fallowing theorem: Let G be a finite group. If G has exactly 2 conjugacy classes of maximal subgroups, then G is solvable. We extend the conjugacy classes to isomorphic classes, and further gen... S. Adnan has proved the fallowing theorem: Let G be a finite group. If G has exactly 2 conjugacy classes of maximal subgroups, then G is solvable. We extend the conjugacy classes to isomorphic classes, and further generalize them to same order classes of maximal subgroups. We obtain the following results. 展开更多
关键词 SUBGROUPS ISOMORPHIC maximal SOLVABLE EXACTLY generalize classES
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Bogomolov Multipliers for Some p-groups of Nilpotency Class 2
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作者 Ivo MICHAILOV 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2016年第5期541-552,共12页
The Bogomolov multiplier B0 (G) of a finite group G is defined as the subgroup of the Schur multiplier consisting of the cohomology classes vanishing after restriction to all abelian subgroups of G. The triviality o... The Bogomolov multiplier B0 (G) of a finite group G is defined as the subgroup of the Schur multiplier consisting of the cohomology classes vanishing after restriction to all abelian subgroups of G. The triviality of the Bogomolov multiplier is an obstruction to Noether's problem. We show that if G is a central product of G1 and G2, regarding Ki ≤ Z(Gi),i = 1,2, and θ : G1 →G2 is a group homomorphism such that its restriction θ|K1 : K1 → K2 is an isomorphism, then the triviality of Bo(G1/K1), Bo(G1) and B0(G2) implies the triviality of Bo(G). We give a positive answer to Noether's problem for all 2-generator p-groups of nilpotency class 2, and for one series of 4-generator p-groups of nilpotency class 2 (with the usual requirement for the roots of unity). 展开更多
关键词 Bogomolov multiplier Noether's problem rationality problem central product of groups p-groups of nilpotency class 2
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Finite Autocapable Groups with the 2-Groups of Maximal Class
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作者 Pengfei Bai Xiuyun Guo Jiao Wang 《Algebra Colloquium》 SCIE CSCD 2024年第4期651-660,共10页
A group H is said to be autocapable if there exists a group M such that H is isomorphic to the absolute central factor group M/L(M)of M.In this paper,we first prove that if N is a characteristic subgroup of an autocap... A group H is said to be autocapable if there exists a group M such that H is isomorphic to the absolute central factor group M/L(M)of M.In this paper,we first prove that if N is a characteristic subgroup of an autocapable group H,then N is neither the generalized quaternion group nor the semi-dihedral group.Next,we give the classification of finite groups G if G/L(G)is a 2-group of maximal class. 展开更多
关键词 autocapable group absolute center 2-group of maximal class
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Finite p-groups whose nonnormal subgroups are metacyclic 被引量:2
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作者 Qiangwei Song Haipeng Qu 《Science China Mathematics》 SCIE CSCD 2020年第7期1271-1284,共14页
For an odd prime p,we give a criterion for finite p-groups whose nonnormal subgroups are metacyclic,and based on the criterion,the p-groups whose nonnormal subgroups are metacyclic are classified up to isomorphism.Thi... For an odd prime p,we give a criterion for finite p-groups whose nonnormal subgroups are metacyclic,and based on the criterion,the p-groups whose nonnormal subgroups are metacyclic are classified up to isomorphism.This solves a problem proposed by Berkovich. 展开更多
关键词 metacyclic groups minimal nonabelian groups minimal nonmetacyclic groups p-groups of maximal class the rank of a p-group
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2维Otsu自适应阈值的快速算法 被引量:121
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作者 郝颖明 朱枫 《中国图象图形学报(A辑)》 CSCD 北大核心 2005年第4期484-488,共5页
Otsu自适应阈值法作为图像阈值分割的经典算法,在图像处理领域得到了广泛的应用,在其基础上发展起来的2维Otsu阈值法却因为计算时间长而制约了其应用。针对2维Otsu自适应阈值方法计算复杂度高的缺点,通过改变2维直方图上的区域划分,将2... Otsu自适应阈值法作为图像阈值分割的经典算法,在图像处理领域得到了广泛的应用,在其基础上发展起来的2维Otsu阈值法却因为计算时间长而制约了其应用。针对2维Otsu自适应阈值方法计算复杂度高的缺点,通过改变2维直方图上的区域划分,将2维阈值转换为1维阈值,从而提高了2维自适应阈值算法的计算速度。实验结果表明,该算法的计算时间远远小于原始2维Otsu算法,分割效果和原始算法基本一致。 展开更多
关键词 自适应阈值 2维 快速算法 图像阈值分割 OTSU算法 计算时间 计算复杂度 经典算法 图像处理 区域划分 阈值转换 计算速度 阈值法 直方图 应用 原始
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