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The first cohomology group of trivial extensions of special biserial algebras 被引量:6
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作者 XU YungeDepartment of Mathematics & Computer Sciences, Hubei University, Wuhan 430062, China 《Science China Mathematics》 SCIE 2004年第4期578-592,共15页
Given a finite dimensional special biserial algebra A with normed basis we obtain the dimension formulae of the first Hochschild homology groups of A and the vector space Alt(DA). As a consequence, an explicit dimensi... Given a finite dimensional special biserial algebra A with normed basis we obtain the dimension formulae of the first Hochschild homology groups of A and the vector space Alt(DA). As a consequence, an explicit dimension formula of the first Hochschild cohomology group of trivial extension TA = A × DA in terms of the combinatorics of the quiver and relations is determined. 展开更多
关键词 HOCHSCHILD (co)homology trivial extension SPECIAL biserial algebra.
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Paradox of voting and the trivial preference set of groupdecision making 被引量:5
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作者 Yuda Hu Hui Cai 《Chinese Science Bulletin》 SCIE EI CAS 1998年第7期550-553,共4页
The structure of the trivial preference set of group decision making is studied, and the essential characters and generating reasons of the paradox of voting are revealed.
关键词 GROUP decision making PARADOX of VOTING one-to-one mapping trivial PREFERENCE set.
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Recollements of extension algebras 被引量:2
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作者 陈清华 林亚南 《Science China Mathematics》 SCIE 2003年第4期530-537,共8页
Let A be a finite-dimensional algebra over arbitrary base fieldk. We prove: if the unbounded derived module category D-(Mod-A) admits symmetric recollement relative to unbounded derived module categories of two finite... Let A be a finite-dimensional algebra over arbitrary base fieldk. We prove: if the unbounded derived module category D-(Mod-A) admits symmetric recollement relative to unbounded derived module categories of two finite-dimensionalk-algebras B and C: then the unbounded derived module category D-(Mod - T(A)) admits symmetric recollement relative to the unbounded derived module categories of T(B) and T(C): 展开更多
关键词 trivial extension algebras derived categories (symmetric) recollements partial TILTING complexes.
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Direct extraction of topological Zak phase with the synthetic dimension 被引量:4
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作者 Guangzhen Li Luojia Wang +6 位作者 Rui Ye Yuanlin Zheng Da-Wei Wang Xiong-Jun Liu Avik Dutt Luqi Yuan Xianfeng Chen 《Light(Science & Applications)》 SCIE EI CSCD 2023年第4期671-679,共9页
Measuring topological invariants is an essential task in characterizing topological phases of matter.They are usually obtained from the number of edge states due to the bulk-edge correspondence or from interference si... Measuring topological invariants is an essential task in characterizing topological phases of matter.They are usually obtained from the number of edge states due to the bulk-edge correspondence or from interference since they are integrals of the geometric phases in the energy band.It is commonly believed that the bulk band structures could not be directly used to obtain the topological invariants.Here,we implement the experimental extraction of Zak phase from the bulk band structures of a Su-Schrieffer-Heeger(SSH)model in the synthetic frequency dimension.Such synthetic SSH lattices are constructed in the frequency axis of light,by controlling the coupling strengths between the symmetric and antisymmetric supermodes of two bichromatically driven rings.We measure the transmission spectra and obtain the projection of the time-resolved band structure on lattice sites,where a strong contrast between the non-trivial and trivial topological phases is observed.The topological Zak phase is naturally encoded in the bulk band structures of the synthetic SSH lattices,which can hence be experimentally extracted from the transmission spectra in a fiber-based modulated ring platform using a laser with telecom wavelength.Our method of extracting topological phases from the bulk band structure can be further extended to characterize topological invariants in higher dimensions,while the exhibited trivial and non-trivial transmission spectra from the topological transition may find future applications in optical communications. 展开更多
关键词 TOPOLOGICAL trivial SYNTHETIC
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琐事与真理——对王建疆“主义的缺位”命题的进一步讨论 被引量:5
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作者 阿列西.艾尔雅维茨 徐薇 《探索与争鸣》 CSSCI 北大核心 2018年第5期68-72,共5页
某个国家和地区在特定的时间内其艺术和人文学科之间会有发展并不一致的现象,这似乎在说明真理的抽象性与具体性之间的矛盾。中国当代在世界上具有引领作用的艺术往往都是"出口产品",与本国的观众无关,而且本国的学者也对此... 某个国家和地区在特定的时间内其艺术和人文学科之间会有发展并不一致的现象,这似乎在说明真理的抽象性与具体性之间的矛盾。中国当代在世界上具有引领作用的艺术往往都是"出口产品",与本国的观众无关,而且本国的学者也对此所知甚少。王建疆教授的"别现代"理论在批判思想欠发达现状的同时,呼吁中国的美学也要领先世界;但在我看来这一主张有些夸张,也未必如此,因为中国美学缺少中国当代艺术那样的内因和影响力。中国美学的出路在于瓦解"同一"与"他者"之间的对立关系。 展开更多
关键词 琐事 真理 中国当代艺术 中国人文学科 领先世界 别现代
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Transport through a quantum dot coupled to two Majorana bound states 被引量:2
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作者 Qi-Bo Zeng Shu Chen +1 位作者 L. You Rong Lu 《Frontiers of physics》 SCIE CSCD 2017年第4期131-141,共11页
We investigate electron transport inside a ring system composed of a quantum dot (QD) coupled to two Majorana bound states confined at the ends of a one-dimensional topological superconductor nanowire. By tuning the... We investigate electron transport inside a ring system composed of a quantum dot (QD) coupled to two Majorana bound states confined at the ends of a one-dimensional topological superconductor nanowire. By tuning the magnetic flux threading through the ring, the model system we consider can be switched into states with or without zero-energy modes when the nanowire is in its topological phase. We find that the Fano profile in the conductance spectrum due to the interference between bound and continuum states exhibits markedly different features for these two different situations, which consequently can be used to detect the Majorana zero-energy mode. Most interestingly, as a periodic function of magnetic flux, the conductance shows 2π periodicity when the two Majorana bound states are nonoverlapping (as in an infinitely long nanowire) but displays 4π periodicity when the overlapping becomes nonzero (as in a finite length nanowire). We map the model system into a QD-Kitaev ring in the Majorana fermion representation and affirm these different characteristics by checking the energy spectrum. 展开更多
关键词 quantum dot Majorana bound states Fano profile QD Kitaev ring topologically trivial and nontrivial
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Second Maximal Invariant Subgroups and Solubility of Finite Groups
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作者 Changguo Shao Antonio Beltrán 《Communications in Mathematics and Statistics》 SCIE CSCD 2024年第1期45-54,共10页
Let G be a finite group and assume that a group of automorphisms A is acting on G such that A and G have coprime orders.We prove that the fact of imposing specific properties on the second maximal A-invariant subgroup... Let G be a finite group and assume that a group of automorphisms A is acting on G such that A and G have coprime orders.We prove that the fact of imposing specific properties on the second maximal A-invariant subgroups of G determines that G is either soluble or isomorphic to a fewnon-soluble groups such as PSL(2,5)or SL(2,5). 展开更多
关键词 Invariant subgroups Coprime action Second maximal subgroup trivial intersection subgroup
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A new method to solve the Reynolds equation including mass-conserving cavitation by physics informed neural networks(PINNs)with both soft and hard constraints
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作者 Yinhu XI Jinhui DENG Yiling LI 《Friction》 SCIE EI CAS CSCD 2024年第6期1165-1175,共11页
In this work,a new method to solve the Reynolds equation including mass-conserving cavitation by using the physics informed neural networks(PINNs)is proposed.The complementarity relationship between the pressure and t... In this work,a new method to solve the Reynolds equation including mass-conserving cavitation by using the physics informed neural networks(PINNs)is proposed.The complementarity relationship between the pressure and the void fraction is used.There are several difficulties in problem solving,and the solutions are provided.Firstly,the difficulty for considering the pressure inequality constraint by PINNs is solved by transferring it into one equality constraint without introducing error.While the void fraction inequality constraint is considered by using the hard constraint with the max-min function.Secondly,to avoid the fluctuation of the boundary value problems,the hard constraint method is also utilized to apply the boundary pressure values and the corresponding functions are provided.Lastly,for avoiding the trivial solution the limitation for the mean value of the void fraction is applied.The results are validated against existing data,and both the incompressible and compressible lubricant are considered.Good agreement can be found for both the domain and domain boundaries. 展开更多
关键词 Reynolds equation mass-conserving cavitation physics informed neural networks hard constraints trivial solution
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琐屑平凡 率真纯情——论丰子恺散文特色 被引量:1
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作者 李力 《河南教育学院学报(哲学社会科学版)》 2005年第1期60-62,共3页
丰子恺是文学家、教育家、美术家。他的散文朴实自然 ,从琐屑平凡中流露率真纯情。宗教、自然、艺术和儿童是丰子恺观察世界的视角和出发点 。
关键词 丰子恺 散文 琐屑 自然 纯情
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Extensions of Symmetric Rings 被引量:3
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作者 王占平 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2007年第2期229-235,共7页
We first consider properties and basic extensions of symmetric rings. We next argue about the symmetry of some kinds of polynomial rings, and show that if R is a reduced ring then R[x]/(x^n) is a symmetric ring, whe... We first consider properties and basic extensions of symmetric rings. We next argue about the symmetry of some kinds of polynomial rings, and show that if R is a reduced ring then R[x]/(x^n) is a symmetric ring, where (x^n) is the ideal generated by x^n and n is a positive integer. Consequently, we prove that for a right Ore ring R with Q its classical right quotient ring, R is symmetric if and only if Q is symmetric. 展开更多
关键词 symmetric ring trivial extension polynomial ring classical right quotient ring
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Advances on topological materials 被引量:4
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作者 Qian Niu 《Frontiers of physics》 SCIE CSCD 2020年第4期33-34,共2页
Topological materials refer to solid structures with topo-logically protected electronic states or other degrees of freedom.A prime example is a Chern insulator in which the occupied bands of states are organized with... Topological materials refer to solid structures with topo-logically protected electronic states or other degrees of freedom.A prime example is a Chern insulator in which the occupied bands of states are organized with a non-trivial topology as characterized by a nonzero Chern in-teger,exhibiting gapless chiral excitations on the bound-aries,which are robust against scatterings. 展开更多
关键词 TOPOLOGICAL trivial EXCITATION
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Weak Graph Map Homotopy and Its Applications
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作者 Conglei ZHANG Yanying WANG +1 位作者 Zhiguo ZHANG Yan ZHAO 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2024年第2期235-252,共18页
The authors introduce a notion of a weak graph map homotopy(they call it M-homotopy),discuss its properties and applications.They prove that the weak graph map homotopy equivalence between graphs coincides with the gr... The authors introduce a notion of a weak graph map homotopy(they call it M-homotopy),discuss its properties and applications.They prove that the weak graph map homotopy equivalence between graphs coincides with the graph homotopy equivalence defined by Yau et al in 2001.The difference between them is that the weak graph map homotopy transformation is defined in terms of maps,while the graph homotopy transformation is defined by means of combinatorial operations.They discuss its advantages over the graph homotopy transformation.As its applications,they investigate the mapping class group of a graph and the 1-order M P-homotopy group of a pointed simple graph.Moreover,they show that the 1-order M P-homotopy group of a pointed simple graph is invariant up to the weak graph map homotopy equivalence. 展开更多
关键词 Weak graph map homotopy trivial vertex Strong deformation retract Mapping class group MP-Homotopy group
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教育的本末倒置10例 被引量:4
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作者 张家 《大学教育科学》 CSSCI 2009年第3期110-112,共3页
在教育领域里存在本末倒置的现象,常常出现于下列关系中:教学与评估,办学质量与"示范学校",好教师与"名师",学术水平与获得课题,高水平与获奖,特色与水平,发展与规范,大学里的学术与行政,世界观、价值观与人生观,... 在教育领域里存在本末倒置的现象,常常出现于下列关系中:教学与评估,办学质量与"示范学校",好教师与"名师",学术水平与获得课题,高水平与获奖,特色与水平,发展与规范,大学里的学术与行政,世界观、价值观与人生观,人与经济。教育中的本末倒置带来严重问题,也说明高等教育改革任务之繁重。 展开更多
关键词 本末倒置 教育
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Double Frobenius algebras 被引量:1
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作者 Zhihua WANG Libin LI 《Frontiers of Mathematics in China》 SCIE CSCD 2018年第2期399-415,共17页
Some equivalent conditions for double Frobenius algebras to be strict ones are given. Then some examples of (strict or non-strict) double Frobenius algebras are presented. Finally, a sufficient and necessary conditi... Some equivalent conditions for double Frobenius algebras to be strict ones are given. Then some examples of (strict or non-strict) double Frobenius algebras are presented. Finally, a sufficient and necessary condition for the trivial extension of a double Frobenius algebra to be a (strict) double Frobenius algebra is given. 展开更多
关键词 Double Frobenius algebra bi-Frobenius algebra trivial extension
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The Projective Cover of the Trivial Representation for a Finite Group of Lie Type in Defining Characteristic
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作者 Shigeo Koshitani Jürgen Müller 《Algebra Colloquium》 SCIE CSCD 2017年第3期439-452,共14页
We give a lower bound of the Loewy length of the projective cover of the trivial module for the group algebra kG of a finite group G of Lie type defined over a finite field of odd characteristic p, where k is an arbit... We give a lower bound of the Loewy length of the projective cover of the trivial module for the group algebra kG of a finite group G of Lie type defined over a finite field of odd characteristic p, where k is an arbitrary field of characteristic p. The proof uses Auslander-Reiten theory. 展开更多
关键词 modular representations projective cover of trivial module finite groups ofLie type in defining characteristic
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Trivial extension of Koszul algebras
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作者 Zhi CHENG 《Frontiers of Mathematics in China》 SCIE CSCD 2017年第5期1045-1056,共12页
Let A be a Koszul algebra, and let M be a graded A-bimodule. We prove that the trivial extension algebra of A by M is also a Koszul algebra whenever M is Koszul as a left A-module. Applications and examples are also p... Let A be a Koszul algebra, and let M be a graded A-bimodule. We prove that the trivial extension algebra of A by M is also a Koszul algebra whenever M is Koszul as a left A-module. Applications and examples are also provided. 展开更多
关键词 Koszul algebra Koszul module trivial extension
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Li Ang's Gendered Dissent in "The Devil in a Chastity Belt"
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作者 Yenna Wu 《Frontiers of Literary Studies in China-Selected Publications from Chinese Universities》 2014年第2期253-276,共24页
Through a close reading, this article explores a few aspects of gendered dissent in Li Ang's story, "The Devil in a Chastity Belt," which reveals the ambivalence and irony of a woman's participation in the Taiwan ... Through a close reading, this article explores a few aspects of gendered dissent in Li Ang's story, "The Devil in a Chastity Belt," which reveals the ambivalence and irony of a woman's participation in the Taiwan Residents opposition movement. Instead of writing a stereotypical work of political fiction for the opposition movement that she supports, Li Ang interrogates the problematic intersection of gender and politics, while reclaiming some of the neglected aspects of oppositional history. While recognizing the inevitability of historical contingency, she nevertheless questions the politically-motivated choice of asceticism, heroism, and sacrifice over individual and familial well-being. Li juxtaposes seemingly trivial and disorderly details of ordinary life against the apparently important and grandiose arena of national politics, creating tension through their interaction and contention. She employs images--including the Devil, the female body, and sensory feelings--to perform gendered dissent. While the lyrical and trivial discourse gradually disrupts the political and didactic, the story's open-ended conclusion inspires complex interpretations of the enigmatic symbol: the Devil wearing a chastity belt. 展开更多
关键词 gendered dissent opposition politics lyrical and trivial discourse political and didactic discourse open-ended conclusion
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ON INDECOMPOSABLE MODULES OVER A REPRESENTATION-FINITE TRIVIAL EXTENSION ALGEBRA
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作者 肖杰 《Science China Mathematics》 SCIE 1991年第2期129-137,共9页
Let T(A)=A?D(A) be a representation-finite trivial extension algebra. We haveproved: (i) every indecomposable module of T(A) is determined by its top and socle, (ii)every indecomposable module of T(A) is determined by... Let T(A)=A?D(A) be a representation-finite trivial extension algebra. We haveproved: (i) every indecomposable module of T(A) is determined by its top and socle, (ii)every indecomposable module of T(A) is determined by its Loewy factors and socal factorsrespectively. 展开更多
关键词 representation-finite trivial EXTENSION Auslander-Reiten QUIVER Loewy factors.
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Knotted pictures of the Bell bases on the surface of a trivial torus
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作者 顾之雨 钱尚武 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期12-18,共7页
By means of the method of torus knot theory, this paper gives the complete processes of obtaining the knotted pictures of four Bell b^es from the knotted pictures of four basic two qubit states.
关键词 knotted picture torus knot theory Bell bases surface of trivial torus
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Directing Components of an Auslander-Reiten Quiver
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作者 章璞 《Science China Mathematics》 SCIE 1993年第3期265-274,共10页
In this paper we give the criteria and constructions of directing compo-nents of a representation-infinite algebra,and the structure of a trivial extension algebraT(A)having Z-component,where A is an iterated-tilted a... In this paper we give the criteria and constructions of directing compo-nents of a representation-infinite algebra,and the structure of a trivial extension algebraT(A)having Z-component,where A is an iterated-tilted algebra. 展开更多
关键词 directing COMPONENT quasi-slice tilted ALGEBRA trivial EXTENSION ALGEBRA
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