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ON ALMOST PRIME SUBMODULES 被引量:2
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作者 Hani A.Khashan 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期645-651,共7页
In this article, we define almost prime submodules as a new generalization of prime and weakly prime submodules of unitary modules over a commutative ring with identity. We study some basic properties of almost prime ... In this article, we define almost prime submodules as a new generalization of prime and weakly prime submodules of unitary modules over a commutative ring with identity. We study some basic properties of almost prime submodules and give some characterizations of them, especially for (finitely generated faithful) multiplication modules. 展开更多
关键词 Prime submodules weakly prime submodules almost prime submodules multiplication modules
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Discrete modulational instability and bright localized spin wave modes in easy-axis weak ferromagnetic spin chains involving the next-nearest-neighbor coupling
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作者 Jiayu Xie Zhihao Deng +1 位作者 Xia Chang Bing Tang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期449-458,共10页
We report a theoretical work on the properties of modulational instability and bright type nonlinear localized modes in one-dimensional easy-axis weak ferromagnetic spin lattices involving next-nearest-neighbor coupli... We report a theoretical work on the properties of modulational instability and bright type nonlinear localized modes in one-dimensional easy-axis weak ferromagnetic spin lattices involving next-nearest-neighbor couplings.With a linear stability analysis, we calculate the growth rates of the modulational instability, and plot the instability regions.When the strength of the next-nearest-neighbor coupling is large enough, two new asymmetric modulational instability regions appear near the boundary of the first Brillouin zone.Furthermore, analytical forms of the bright nonlinear localized modes are constructed by means of a quasi-discreteness approach.The influence of the next-nearest-neighbor coupling on the Brillouin zone center mode and boundary mode are discussed.In particular, we discover a reversal phenomenon of the propagation direction of the Brillouin zone boundary mode. 展开更多
关键词 modulational instability analysis intrinsic LOCALIZED SPIN-WAVE MODES weak FERROMAGNETS NEXT-NEAREST-NEIGHBOR COUPLINGS
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Passive decoy-state quantum key distribution using weak coherent pulses with modulator attenuation
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作者 李源 鲍皖苏 +2 位作者 李宏伟 周淳 汪洋 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期118-124,共7页
Passive decoy-state quantum key distribution is more desirable than the active one in some scenarios. It is also affected by the imperfections of the devices. In this paper, the influence of modulator attenuation on t... Passive decoy-state quantum key distribution is more desirable than the active one in some scenarios. It is also affected by the imperfections of the devices. In this paper, the influence of modulator attenuation on the passive decoy-state method is considered. We introduce and analyze the unbalanced Mach-Zehnder interferometer, briefly, and combining with the virtual source and imaginary unitary transformation, we characterize the passive decoy-state method using a weak coherent photon source with modulator attenuation. According to the attenuation parameter 6, the pass efficiencies are given. Then, the key generation rate can be acquired. From numerical simulations, it can be seen that modulator attenuation has a non- negligible influence on the performance of passive-state QKD protocol. Based on the research, the analysis method of virtual source and imaginary unitary transformation are preferred in analyzing passive decoy state protocol, and the passive decoy-state method is better than the active one and is close to the active vacuum + weak decoy state under the condition of having the same modulator attenuation. 展开更多
关键词 quantum key distribution passive decoy state modulator attenuation weak coherent pulses
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EXPLICIT DESCRIPTION OF A CLASS OF INDECOMPOSABLE INJECTIVE MODULES
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作者 M.R.Pournaki M.Tousi 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期511-514,共4页
Let R be a commutative Noetherian ring and p be a prime ideal of R such that the ideal pRp is principal and ht(p)≠0. In this note, the anthors describe the explicit structure of the injective envelope of the R-module... Let R be a commutative Noetherian ring and p be a prime ideal of R such that the ideal pRp is principal and ht(p)≠0. In this note, the anthors describe the explicit structure of the injective envelope of the R-module R/p. 展开更多
关键词 Noetherian ring injective module indecomposable injective module injective envelope weakly locally principal prime ideal
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Hopf Modules in the Category of Yetter-Drinfeld Modules
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作者 Yanmin Yin 《Applied Mathematics》 2016年第7期629-637,共9页
We give the Fundamental Theorem for Hopf modules  in the category of Yetter-Drinfeld modules , where L is a quasitriangular weak Hopf algebra with a bijective antipode. We also show that H* has a right H-Hopf mod... We give the Fundamental Theorem for Hopf modules  in the category of Yetter-Drinfeld modules , where L is a quasitriangular weak Hopf algebra with a bijective antipode. We also show that H* has a right H-Hopf module structure in the Yetter-Drinfeld category. As an application we deduce the existence and uniqueness of right integral from it. 展开更多
关键词 weak Hopf Algebra Hopf module Fundamental Theorem
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On the Structure of the B-cocleft Module Coalgebra
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作者 焦争鸣 王栓宏 赵文正 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第4期44-47, ,共4页
In this paper we develope the notions of crossed coproduct of Hopf algebras and study an equivalent theorem of generalized crossed coproduct of H weakly comodule coalgebras and H module coalgebras. The main result is ... In this paper we develope the notions of crossed coproduct of Hopf algebras and study an equivalent theorem of generalized crossed coproduct of H weakly comodule coalgebras and H module coalgebras. The main result is to prove a structure theorem about B cocleft H module coalgebras. 展开更多
关键词 H module coalgebra H weakly comodule coalgebra crossed coproduct
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Interpolation Problems for Nest Algebra Modules
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作者 李鹏同 鲁世杰 《Northeastern Mathematical Journal》 CSCD 2002年第4期323-329,共7页
Let U be a weakly closed nest algebra module acting on a Hilbert space H. Given two operators X and Y in B(H), a necessary and sufficient condition for the existence of an operator T in U satisfying TX = Y is provided.
关键词 nest algebra weakly closed nest algebra module INTERPOLATION
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Temporally Modulated Phase Retrieval Method for Weak Temporal Phase Measurement of Laser Pulses
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作者 姚玉东 乔治 +2 位作者 汪小超 范薇 林尊琪 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第3期29-33,共5页
We propose a simple iterative algorithm based on a temporally movable phase modulation process to retrieve the weak temporal phase of laser pulses. This unambiguous method can be used to achieve a high accuracy and to... We propose a simple iterative algorithm based on a temporally movable phase modulation process to retrieve the weak temporal phase of laser pulses. This unambiguous method can be used to achieve a high accuracy and to simultaneously measure the weak temporal phase and temporal profile of pulses, which are almost transform- limited. A detailed analysis shows that this iterative method has valuable potential applications in the charac- terization of pulses with weak temporal phase. 展开更多
关键词 Temporally modulated Phase Retrieval Method for weak Temporal Phase Measurement of Laser Pulses
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Weak Co-AB-context for G_(C)-χ-injective Modules
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作者 YANG Qiang 《数学进展》 2026年第1期103-119,共17页
In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses... In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses,some properties and some equivalent characterizations of G_(C)-X-injective modules are investigated,and we also show that the triple(■,cores■,■)is a weak co-AB-context.As an application,two complete cotorsion pairs and a new model structure in Mod S are given. 展开更多
关键词 C-X-injective module G_(C)-X-injective module cotorsion pair weak co-ABcontext
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基于循环移频环的啁啾信号光学产生方法研究
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作者 赵硕 张静 +3 位作者 张一博 王云新 濮环宇 张钰 《科学技术创新》 2026年第1期18-22,共5页
线性啁啾信号是一种频率随时间线性变化的信号,因其优异的脉冲压缩性能,在雷达探测、传感等领域具有广泛应用。本文研究了一种基于光学循环移频环路的线性啁啾信号产生方法。该方法首先将窄带线性啁啾信号调制到光信号上,随后利用循环... 线性啁啾信号是一种频率随时间线性变化的信号,因其优异的脉冲压缩性能,在雷达探测、传感等领域具有广泛应用。本文研究了一种基于光学循环移频环路的线性啁啾信号产生方法。该方法首先将窄带线性啁啾信号调制到光信号上,随后利用循环移频环路拓展信号的频率范围,从而获得频率步进的宽带线性啁啾信号。利用所生成的啁啾信号对弱反射光纤光栅阵列的光栅间距进行了测量。实验结果表明,啁啾信号的带宽由100 MHz拓展至2 GHz,测得的光栅间距平均值为9.8 m。通过该系统的课堂演示,有助于学生深入理解微波信号的光学产生原理和方法,并使其掌握光电子器件的使用技巧。另外,通过与实际应用相结合,增强学生的综合实践能力与创新意识。 展开更多
关键词 线性啁啾信号 光学循环移频环路 双平行马赫曾德尔调制器 声光调制器 弱反射光纤光栅阵列
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On Weakly P.P. Rings 被引量:1
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作者 Xiang Yue-ming Ouyang Lun-qun +1 位作者 Wang Shu-gui Du Xian-kun 《Communications in Mathematical Research》 CSCD 2015年第4期362-372,共11页
We introduce, in this paper, the right weakly p.p. rings as the generaliza- tion of right p.p. rings. It is shown that many properties of the right p.p. rings can be extended onto the right weakly p.p. rings. Relative... We introduce, in this paper, the right weakly p.p. rings as the generaliza- tion of right p.p. rings. It is shown that many properties of the right p.p. rings can be extended onto the right weakly p.p. rings. Relative examples are constructed. As applications, we also characterize the regular rings and the semisimple rings in terms of the right weakly p.p. rings. 展开更多
关键词 weakly p.p. ring GP-injective module regular ring
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SYMMETRIES IN YETTER-DRINFELD CATEGORIES OVER WEAK HOPF ALGEBRAS
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作者 高楠 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期870-876,共7页
This article is devoted to the study of the symmetry in the Yetter-Drinfeld category of a finite-dimensional weak Hopf algebra.It generalizes the corresponding results in Hopf algebras.
关键词 weak Hopf algebra Yetter-Drinfeld module SYMMETRY
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Picosecond supercontinuum generation seeded by a weak continuous wave
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作者 李荧 侯静 +2 位作者 冷进勇 王文亮 姜宗福 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期214-217,共4页
We experimentally investigate the spectral details of a picosecond supercontinuum pumped at 1064 nm and seeded by a weak continuous wave (~20000 times weaker than the pulse peak power) at several power levels in ph... We experimentally investigate the spectral details of a picosecond supercontinuum pumped at 1064 nm and seeded by a weak continuous wave (~20000 times weaker than the pulse peak power) at several power levels in photonic crystal fibers. Seeding at different wavelengths leads to different spectral details and the effects to the bandwidth of supercontinuum are also distinct. Spectra can be widened when seeded by a continuous wave at 1070 nm and narrowed by ~100 nm when seeded at 1080 nm. The influence is enhanced by increasing the average seeded power. 展开更多
关键词 supercontinuum seeded by a weak continuous wave modulation instability four-wave mixing
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Synergistic engineering of cobalt selenide and biomass-derived S,N,P co-doped hierarchical porous carbon for modulation of stable Li-S batteries
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作者 Yang Lin Song He +5 位作者 Zhiyong Ouyang Jianchao Li Jie Zhao Yanhe Xiao Shuijin Lei Baochang Cheng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第3期11-21,共11页
Hierarchical porous carbon co-doped with heterogeneous atoms has attracted much attention thanks to sizable internal void space accommodating electrolyte,high-density microporous structure physically con-fining polysu... Hierarchical porous carbon co-doped with heterogeneous atoms has attracted much attention thanks to sizable internal void space accommodating electrolyte,high-density microporous structure physically con-fining polysulfides(LPS),and heterogeneous atoms serving as active sites to capture LPS.However,solely relying on carbon material defects to capture LPS proves ineffective.Hence,metal compounds must be introduced to chemisorb LPS.Herein,cobalt ions are in-situ grown on the polydopamine layer coated on the surface of biomass-derived S,N,P co-doped hierarchical porous carbon(SNP-PC).Then a layer of nitrogen-doped porous carbon(MPC)dotted with CoSe nanoparticles is acquired by selenizing.Thus,a strong-polar/weak-polar composite material of SNP-PC studded with CoSe nanoparticles is obtained(SNP-PC@MPC@CoSe).Button cells assembled with SNP-PC@MPC@CoSe-modified separator enable superb long-cycle stability and satisfactory rate performance.An excellent rate capacity of 796 mAh g^(−1)at a high current rate of 4 C with an ultra-low capacity fading of 0.06%over 700 cycles can be acquired.More impressively,even in a harsh test condition of 5.65 mg cm^(−2)sulfur loading and 4μL mg^(−1)ratio of electrolyte to active materials,the battery can still display a specific capacity of 980 mAh g^(−1)(area capacity of∼5.54 mAh cm^(−2))at 0.1 C.This work provides a promising route toward high-performance Li-S batteries. 展开更多
关键词 Lithium-sulfur battery Biomass conversion S N P-codoped porous carbon CoSe modulation Multifunctional separator Synergism of strong and weak polarity
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基于热流计的微弱信号检测系统 被引量:1
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作者 尚泽 张磊 谭秋林 《舰船电子工程》 2025年第1期191-196,共6页
测量热流密度这一参数时,当面对极端恶劣环境和工作空间限制的双重问题时,热流传感器不仅需要耐高温还要做到小型化设计,会导致其输出电势小,噪声大,导致被测信号的瞬态非平稳性开始凸显,信噪比降低。放大有用信号,抑制噪声可以有效提... 测量热流密度这一参数时,当面对极端恶劣环境和工作空间限制的双重问题时,热流传感器不仅需要耐高温还要做到小型化设计,会导致其输出电势小,噪声大,导致被测信号的瞬态非平稳性开始凸显,信噪比降低。放大有用信号,抑制噪声可以有效提高信噪比,为此提出了一种基于高温热流传感器的微弱信号检测方法。在信号检测的过程中,通过斩波器和相敏检波器实时调制解调被测信号,降低噪声水平,提高检测精度,从而实现微弱信号的检测。经过测试表明,当测量高温环境下的热流传感器时,所设计电路具有较好的测试效果,相对误差最大仅为17μV。该研究为设计具有微弱信号检测能力的测量仪器提供了一种新的方法,也为推动高温热流传感器在需要高精度热流管理的应用场景方面发挥了重要作用。 展开更多
关键词 高温热流传感器 微弱信号 调制解调 相敏检波
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Remarks on Gorenstein Weak Injective and Weak Flat Modules 被引量:8
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作者 Tiwei Zhao Yunge Xu 《Algebra Colloquium》 SCIE CSCD 2020年第4期687-702,共16页
In this paper,we introduce Gorenstein weak injective and weak flat modules in terms of,respectively,weak injective and weak flat modules;the classes of Gorenstein weak injective and weak flat modules are larger than t... In this paper,we introduce Gorenstein weak injective and weak flat modules in terms of,respectively,weak injective and weak flat modules;the classes of Gorenstein weak injective and weak flat modules are larger than the classical classes of Gorenstein injective and flat modules.In this new setting,we characterize rings over which all modules are Gorenstein weak injective.Moreover,we discuss the relation between the weak cosyzygy and Gorenstein weak cosyzygy of a module,and also the stability of Gorenstein weak injective modules. 展开更多
关键词 weak injective module weak flat module Gorenstein weak injective module Gorenstein weak flat module cosyzygy
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基于改进CORDIC算法的DFT解调方法
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作者 焦宇涛 曹胜利 +1 位作者 岳钊 赵二刚 《南开大学学报(自然科学版)》 北大核心 2025年第3期59-65,共7页
调制解调法是一种常用的微弱信号检测方法,高精度、低复杂度的解调方法的实现对于调制解调法的应用具有重要的意义.传统坐标旋转数字计算(coordinate rotation digital computer,CORDIC)算法具有占用资源多,需要缩放因子补偿等问题.因... 调制解调法是一种常用的微弱信号检测方法,高精度、低复杂度的解调方法的实现对于调制解调法的应用具有重要的意义.传统坐标旋转数字计算(coordinate rotation digital computer,CORDIC)算法具有占用资源多,需要缩放因子补偿等问题.因此设计并实现了一种基于改进CORDIC算法的离散傅里叶变换(discrete Fourier transform,DFT)解调方法用于微弱信号的检测.首先改进了传统的CORDIC算法用于正余弦函数值的计算,该方法不仅免除了缩放因子,而且不需要进行旋转角度的判断,降低了算法的资源占用;然后基于该CORDIC算法设计了DFT解调算法,避免了乘法器与大量查找表的使用.最终仿真结果表明,设计的DFT解调方法在整周期采样的情况下能够实现对调制信号的高精度解调,并且具备良好的抗噪声性能,能够满足微弱信号检测的要求. 展开更多
关键词 DFT解调 免缩放因子CORDIC 调制解调法 微弱信号检测
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基于CELMDAN与IMOMEDA的微弱机械特征增强方法 被引量:1
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作者 顾张清 黄清岩 +1 位作者 任世锦 郝国生 《常州大学学报(自然科学版)》 2025年第3期75-86,92,共13页
针对设备背景噪声影响机械故障检测的问题,提出一种融合自适应噪声完全集成局部均值分解(Complete Ensemble Local Mean Decomposition with Adaptive Noise,CELMDAN)与改进的多点最优最小熵去卷积调整(Improved Multipoint Optimal Min... 针对设备背景噪声影响机械故障检测的问题,提出一种融合自适应噪声完全集成局部均值分解(Complete Ensemble Local Mean Decomposition with Adaptive Noise,CELMDAN)与改进的多点最优最小熵去卷积调整(Improved Multipoint Optimal Minimum Entropy Deconvolution Adjusted,IMOMEDA)的微弱机械特征增强方法。该方法首先利用CELMDAN方法把复杂振动信号分解为多个单模态的乘积函数(Product Functions,PFs),解决了集成局部均值分解(Ensemble Local Mean Decomposition,ELMD)对信号施加噪声幅值和试错次数难以确定的问题。其次,提出一种具有鲁棒性较强、物理意义明确以及尺度不变性的周期调制强度(Periodic Modulation Intensity,PMI),以筛选出有效的PFs。接着,针对所选PFs中的噪声,提出IMOMEDA方法进行消除,该方法通过迭代估计最优模型参数,自适应地提取振动信号中的周期性故障瞬态特征,能够在频域中定位瞬态的谱峭度,从而抽取被背景噪声淹没的微弱故障特征。最后,以煤矿提升机为研究对象,设计了多种振动信号特征增强方法对比实验、机械运行状态诊断性能实验以及信号特征增强算法性能对比实验,多角度验证了本文方法的有效性。 展开更多
关键词 微弱故障信号增强 改进的多点最优最小熵去卷积调整 自适应噪声完全集成局部均值分解 周期调制强度 煤矿提升机
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Weak Gorenstein Cotorsion Modules 被引量:2
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作者 Liang Zhao Jiaqun Wei Jiangsheng Hu 《Algebra Colloquium》 SCIE CSCD 2018年第2期265-276,共12页
Let R be a ring and let be the class of strongly Gorenstein fiat right R-modules. We call a right R-module M a weak Gorenstein cotorsion module if M is in the class ⊥. Properties of weak Gorenstein cotorsion modu... Let R be a ring and let be the class of strongly Gorenstein fiat right R-modules. We call a right R-module M a weak Gorenstein cotorsion module if M is in the class ⊥. Properties of weak Gorenstein cotorsion modules are investigated. It is shown that weak Gorenstein cotorsion R-modules over coherent rings are indeed weaker than Gorenstein cotorsion R-modules. Weak Gorenstein cotorsion dimension for modules and rings are also studied. 展开更多
关键词 weak Gorenstein cotorsion module weak Gorenstein cotorsion injective dimension global weak Corenstein cotorsion dimension
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Yetter–Drinfeld Modules over Weak Braided Hopf Monoids and Center Categories 被引量:1
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作者 Jos Nicanor ALONSO LVAREZ Ramón GONZLEZ RODRIGUEZ Carlos SONEIRA CALVO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2014年第4期567-590,共24页
In this paper, we introduce several centralizer constructions in a monoidal context and establish a monoidal equivalence with the category of Yetter-Drinfeld modules over a weak braided Hopf monoid. We apply the gener... In this paper, we introduce several centralizer constructions in a monoidal context and establish a monoidal equivalence with the category of Yetter-Drinfeld modules over a weak braided Hopf monoid. We apply the general result to the calculus of the center in module categories. 展开更多
关键词 weak (braided) Hopf monoid Yetter-Drinfeld module CENTER
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