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Characterizations of m-weak group inverses
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作者 Zhou Yukun Chen Jianlong 《Journal of Southeast University(English Edition)》 EI CAS 2024年第3期313-318,共6页
To characterize m-weak group inverses,several algebraic methods are used,such as the use of idempotents,one-side principal ideals,and units.Consider an element a within a unitary ring that possesses Drazin invertibili... To characterize m-weak group inverses,several algebraic methods are used,such as the use of idempotents,one-side principal ideals,and units.Consider an element a within a unitary ring that possesses Drazin invertibility and an involution.This paper begins by outlining the conditions necessary for the existence of the m-weak group inverse of a.Moreover,it explores the criteria under which a can be considered pseudo core invertible and weak group invertible.In the context of a weak proper*-ring,it is proved that a is weak group invertible if,and only if,a D can serve as the weak group inverse of au,where u represents a specially invertible element closely associated with a D.The paper also introduces a counterexample to illustrate that a D cannot universally serve as the pseudo core inverse of another element.This distinction underscores the nuanced differences between pseudo core inverses and weak group inverses.Ultimately,the discussion expands to include the commuting properties of weak group inverses,extending these considerations to m-weak group inverses.Several new conditions on commuting properties of generalized inverses are given.These results show that pseudo core inverses,weak group inverses,and m-weak group inverses are not only closely linked but also have significant differences that set them apart. 展开更多
关键词 m-weak group inverse weak group inverse Drazin inverse commuting property
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Weighted weak group inverse for Hilbert space operators 被引量:4
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作者 Dijana MOSIC Daochang ZHANG 《Frontiers of Mathematics in China》 SCIE CSCD 2020年第4期709-726,共18页
We present the weighted weak group inverse,which is a new generalized inverse of operators between two Hilbert spaces,and we extend the notation of the weighted weak group inverse for rectangular matrices.Some charact... We present the weighted weak group inverse,which is a new generalized inverse of operators between two Hilbert spaces,and we extend the notation of the weighted weak group inverse for rectangular matrices.Some characterizations and representations of the weighted weak group inverse are investigated.We also apply these results to define and study the weak group inverse for a Hilbert space operator.Using the weak group inverse,we define and characterize various binary relations. 展开更多
关键词 weak group inverse weighted core-EP inverse Wg-Drazin inverse Hilbert space
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Weakly coordinating group directed rhodium-catalyzed unconventional site-selective C-H olefination of indolizines at the 8-position
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作者 Xue Feng Jiaxin Tian +5 位作者 Ying Sun Huayou Hu Mingzhu Lu Yuhe Kan Danjun Fang Chao Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第1期470-474,共5页
A rhodium-catalyzed directing group promoted selective C-H olefination reaction of indolizines at the 8-position is re ported.Di-olefination at 2,8-positions also achieved with silver hexafluoroantimonate as an additi... A rhodium-catalyzed directing group promoted selective C-H olefination reaction of indolizines at the 8-position is re ported.Di-olefination at 2,8-positions also achieved with silver hexafluoroantimonate as an additive under similar reaction conditions.Weakly coordinating groups,such as ketone,alde hyde,amide and ester,were used as directing groups.The ester group can be removed under acid conditions and therefore is used as a traceless directing group. 展开更多
关键词 RHODIUM-CATALYZED C–H olefination INDOLIZINE weakly coordinating directing group Unconventional site-selectivity
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Quantum Decoherence of Neutrino Oscillation and Weak Measurement about Its Group Velocity
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作者 玉素甫.吐拉克 徐大智 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第12期801-808,共8页
We theoretically explore the possibility of observing the quantum decoherence of neutrino oscillation due to the vacuum dispersion, that the wave-packet of neutrino spatially splits according to the different velociti... We theoretically explore the possibility of observing the quantum decoherence of neutrino oscillation due to the vacuum dispersion, that the wave-packet of neutrino spatially splits according to the different velocities of two mass eigenstates. We find that if this decoherence could be observed and the range of values of the mixing angle is known, then the superluminal neutrino phenomena could occur for some mixing angles as the consequence of a weak measurement about flavor mixing in the neutrino propagation. Our calculation gives the explicit dependence of group velocity shift to the decoherence factor and the weak value of neutrino's pre and post-selected states. We also study the related problems for the neutrino oscillation with three generations. 展开更多
关键词 weak MEASUREMENT NEUTRINO OSCILLATION group VELOCITY SHIFT
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Weak Isomorphism of Finite Group
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作者 蒲伟 何军华 《Journal of Southwest Jiaotong University(English Edition)》 2007年第1期80-83,共4页
On the basis of the quasi-isomorphism of finite groups, a new mapping, weak isomorphism, from a finite group to another finite group is defined. Let G and H be two finite groups and G be weak-isomorphic to H. Then G≌... On the basis of the quasi-isomorphism of finite groups, a new mapping, weak isomorphism, from a finite group to another finite group is defined. Let G and H be two finite groups and G be weak-isomorphic to H. Then G≌H if G satisfies one of the following conditions. 1) G is a finite Abelian group. 2) The order of G is p^3. 3 ) The order of G is p^n+1 and G has a cyclic normal subgroup N = 〈a〉 of order p^n. 4) G is a nilpotent group and if p^││G│, then for any P ∈ Sylp (G), P has a cyclic maximal subgroup, where p is a prime; 5) G is a maximal class group of order p4(p〉3). 展开更多
关键词 weak isomorphism Finite Abelian group Nilpotent gtoup p-Cvtoup
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Endpoints of Multi-Valued Weak Contractions on the Metric Space of Partially Ordered Groups
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作者 Congdian Cheng 《Advances in Pure Mathematics》 2022年第11期638-651,共14页
The present work considers the endpoint in the abstract metric space. It firstly introduces the metric space of partially ordered groups and the metric space of partially ordered modules, respectively;and defines the ... The present work considers the endpoint in the abstract metric space. It firstly introduces the metric space of partially ordered groups and the metric space of partially ordered modules, respectively;and defines the convergence of sequences and the multi-valued weak contractions, etc., on the introduced space. And then, with the methods of functional analysis and abstract algebra, it successively establishes an endpoint theorem for the metric space of partially ordered groups and an endpoint theorem for the metric space of partially ordered modules. The contributions of this article extend the theory of cone metric space constructed by Huang and Zhang (2007) and some recent results on the fixed point and endpoint theory, such as the endpoint theorem given by Amini-Harandi (2010). 展开更多
关键词 Fixed Point Endpoint Metric Space Valued in Partially Ordered group Topological Structure weak Contraction
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On Weak Braided T-category
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作者 史美华 贾玲 《Chinese Quarterly Journal of Mathematics》 2016年第3期248-259,共12页
Recently Turaev generalized the notion of a tensor category to that of a crossed group category.In[5]the authors constructed the representation category Rep(H) of a T-coalgebra H.In[2]the authors introduced the notion... Recently Turaev generalized the notion of a tensor category to that of a crossed group category.In[5]the authors constructed the representation category Rep(H) of a T-coalgebra H.In[2]the authors introduced the notions of a weak tensor category to characterize a weak bialgebra and a weak Hopf algebra.This paper is based on these ideas to naturally introduce the notions of a weak T-category and a weak braided T-category which are not under the usual way and prove that the categories of representations of a weak T-coalgebra and a weak braided T-coalgebra are a weak T-category and a weak braided T-category respectively.Furthermore we also discuss some properties of weak T-category. 展开更多
关键词 weak T-coalgebra braided weak T-coalgebra weak crossed group category braided weak crossed group category
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Weak Hopf Algebras Corresponding to the Non-Standard Deformation of Type B_n
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作者 Cheng CHENG Shilin YANG 《Journal of Mathematical Research with Applications》 CSCD 2018年第6期567-576,共10页
We introduce a non-standard quantum group Xq(Bn) of type Bn which is a Hopf algebra. Then we replace the group of grouplike elements of Xq(Bn), and obtain a weak Hopf algebra wXq(Bn). Finally, we describe the Ex... We introduce a non-standard quantum group Xq(Bn) of type Bn which is a Hopf algebra. Then we replace the group of grouplike elements of Xq(Bn), and obtain a weak Hopf algebra wXq(Bn). Finally, we describe the Ext-quiver of wXq(Bn) as a coalgebra. 展开更多
关键词 non-standard quantum group weak Hopf algebra Ext quiver
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A Riesz Product Type Measure on the Cantor Group
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作者 SHI QI-YAN 《Communications in Mathematical Research》 CSCD 2010年第1期7-16,共10页
A Riesz type product as Pn=nЛj=1(1+awj+bwj+1)is studied, where a, b are two real numbers with |a| + |b| 〈 1, and {wj} are indepen- dent random variables taking values in (-1, 1} with equal probability. Le... A Riesz type product as Pn=nЛj=1(1+awj+bwj+1)is studied, where a, b are two real numbers with |a| + |b| 〈 1, and {wj} are indepen- dent random variables taking values in (-1, 1} with equal probability. Let dw be the normalized Haar measure on the Cantor group Ω = (-1, 1}^N. The sequence of P,~dw 1 probability measures {Pndw/E(Pn) } is showed to converge weakly to a unique continuous measure on/2, and the obtained measure is singular with respect to dw. 展开更多
关键词 Riesz product Cantor group weak topology singularity of measure 2000 MR subject classification- 42A55 28A33
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弱对偶Drazin逆的性质及刻画
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作者 王宏兴 凌秋丽 +1 位作者 蒋添合 LIU Shuangzhe 《数学年刊(A辑)》 北大核心 2025年第2期169-186,共18页
对偶Drazin逆是一种重要的对偶广义逆.作者为了推广它,引入了对任意对偶方阵都唯一存在的弱对偶Drazin逆.当对偶Drazin逆存在时,它与弱对偶Drazin逆等价.此外,作者还引入了弱对偶群逆,并将其应用于一类约束对偶矩阵方程的研究.
关键词 对偶Drazin逆 对偶群逆 弱对偶Drazin逆 弱对偶群逆
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Electro-Weak Gauge, Weinberg-Salam Angle
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作者 Claude Daviau Jacques Bertrand 《Journal of Modern Physics》 2015年第14期2080-2092,共13页
The main aim of this paper is to explain why the Weinberg-Salam angle in the electro-weak gauge group satisfies . We study the gauge potentials of the electro-weak gauge group from our wave equation for electron + neu... The main aim of this paper is to explain why the Weinberg-Salam angle in the electro-weak gauge group satisfies . We study the gauge potentials of the electro-weak gauge group from our wave equation for electron + neutrino. These potentials are space-time vectors whose components are amongst the tensor densities without derivative built from the three chiral spinors of the wave. The ?gauge invariance allows us to identify the four potential space-time vectors of the electro-weak gauge to four of the nine possible vectors. One and only one of the nine derived bivector fields is the massless electromagnetic field. Putting back the four potentials linked to the spinor wave into the wave equation we get simplified equations. From the properties of the second-order wave equation we obtain the Weinberg-Salam angle. We discuss the implications of the simplified equations, obtained without second quantification, on mass, charge and gauge invariance. Chiral gauge, electric gauge and weak gauge are simply linked. 展开更多
关键词 Invariance group Dirac Equation Chirality Electron Neutrino Electro-weak GAUGE GAUGE Bosons Photon Weinberg-Salam Angle
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基于代谢组学的中华蜜蜂群势强弱相关机制研究
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作者 邓晓银 武敏 +3 位作者 徐凯 牛庆生 郭丽娜 郭媛 《应用昆虫学报》 北大核心 2025年第3期731-740,共10页
【目的】旨在探究中华蜜蜂Apis cerana cerana强群和弱群的相关代谢差异及潜在分子调控机制。【方法】通过液相色谱-质谱联用(Liquid chromatography-mass spectrometry,LC-MS)联用的非靶向代谢组学筛选中华蜜蜂强群和弱群之间的差异代... 【目的】旨在探究中华蜜蜂Apis cerana cerana强群和弱群的相关代谢差异及潜在分子调控机制。【方法】通过液相色谱-质谱联用(Liquid chromatography-mass spectrometry,LC-MS)联用的非靶向代谢组学筛选中华蜜蜂强群和弱群之间的差异代谢物,并进行KEGG富集分析。利用生化方法测定谷胱甘肽S-转移酶(GST)、超氧化物歧化酶(SOD)和细胞色素P450(CYP450)活性。【结果】中华蜜蜂强群和弱群的工蜂在代谢组学检测到的正、负离子模式下分别有616和212个差异代谢物,注释后筛选到甜菜碱、黄酮类化合物、赖氨酸磷脂酸等与蜜蜂抗氧化、抗炎、抗菌、防止细胞凋亡相关的代谢物。中华蜜蜂强弱群间的差异代谢物显著富集于CYP450、AMPK信号通路、谷胱甘肽代谢、精氨酸生物合成、生热作用、叶酸生物合成等代谢通路。此外,工蜂强群体内CYP450浓度,SOD及GST活性均高于弱群。【结论】中华蜜蜂强群与弱群在代谢物组成上存在显著差异,强群中工蜂的抗氧化应激、能量代谢、抵御外界环境温度和有害物质侵害、抗炎抗菌的能力更强。 展开更多
关键词 中华蜜蜂 强群 弱群 非靶向代谢组 差异代谢物
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新生儿ABO血型抗原弱表达的基因分析 被引量:2
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作者 杨佳丽 赵鼎 +3 位作者 李巍 张笑盼 李志浩 田冬冬 《中国输血杂志》 2025年第1期85-90,96,共7页
目的对新生儿ABO血型抗原弱凝集和混合凝集的标本进行基因分析,探讨新生儿ABO亚型分子生物学特性。方法采用试管法和微柱凝胶法进行ABO血型的血清学鉴定,PCR法扩增其ABO基因第2~7外显子,扩增产物用Sanger测序法进行基因测序,判断基因型... 目的对新生儿ABO血型抗原弱凝集和混合凝集的标本进行基因分析,探讨新生儿ABO亚型分子生物学特性。方法采用试管法和微柱凝胶法进行ABO血型的血清学鉴定,PCR法扩增其ABO基因第2~7外显子,扩增产物用Sanger测序法进行基因测序,判断基因型。结果14例新生儿ABO血型血清学结果中A抗原减弱8例,B抗原减弱6例,有7例标本检出ABO亚型等位基因,基因型分别为A102/B101+c.538C>T、Aw26/B102、A205/O02、A205/B101(2例)、Aw26/O02、B(A)06/O01、B101/O01(3例)、A102/O01(2例)、A102/B101、B101/O02。此外,在对携带B(A)06等位基因患者的家系调查中发现另外3名家庭成员同样携带该等位基因。结论对于新生儿ABO血型鉴定中抗原减弱的标本,除了年龄因素有必要考虑ABO亚型的可能,借助基因检测可防止新生儿ABO亚型的漏检。 展开更多
关键词 新生儿 ABO血型 抗原弱表达 ABO亚型 基因测序
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双桥山群变质砂岩区含软层滑坡机理
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作者 刘清 甘建军 +2 位作者 陈浩 李小明 刘玉伟 《地质科技通报》 北大核心 2025年第1期185-193,共9页
双桥山群地层在华东地区广泛揭露,岩性与地层复杂,断层及褶皱发育,常形成软弱夹层斜坡,在降雨入渗的作用下极易发生滑坡。为揭示其在降雨条件下变形演化机理,以江西省修水县一典型含粉质黏土软弱夹层堆积体滑坡为例,分析了该软弱夹层滑... 双桥山群地层在华东地区广泛揭露,岩性与地层复杂,断层及褶皱发育,常形成软弱夹层斜坡,在降雨入渗的作用下极易发生滑坡。为揭示其在降雨条件下变形演化机理,以江西省修水县一典型含粉质黏土软弱夹层堆积体滑坡为例,分析了该软弱夹层滑坡的形成原因和变形破坏特征,建立了堆积体滑坡的地质力学模型,采用GeoStudio数值分析软件模拟了该滑坡在不同降雨强度条件下的形成机理。研究结果表明:(1)滑坡后缘EW向断层与韧性断裂带共同作用,发育了4组控制坡体稳定性的裂隙,在滑床之上形成厚达8.8 m的船形软弱夹层。(2)降雨入渗到碎屑和黏土物质组成的滑带,使滑体经历前期蠕变-中期滑动面贯通-后期剪切变形3个变形破坏阶段。(3)当降雨强度达9.9 mm/d时,滑坡坡体开始蠕变;当降雨强度增加到40 mm/d时,坡体沿着软弱结构面剪切变形增大;当降雨强度上升至120 mm/d时,坡体沿着软层结构面产生贯通性破碎面,最终加速失稳破坏。研究结果对今后该类似岩群的滑坡灾害的防治具有一定的参考价值。 展开更多
关键词 双桥山群 岩质滑坡 软弱夹层 降雨入渗 数值模拟 变质砂岩
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^(*)-环中m-e-弱群逆和右m-e-弱群逆的若干性质
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作者 李梦雨 宋贤梅 《安徽师范大学学报(自然科学版)》 2025年第5期401-407,共7页
首先在^(*)-环上给出了m-e弱群逆存在的充分必要条件,作为应用证明了正则元a是(m+1)-e-弱群逆当且仅当a2a-是m-e弱群逆的,其中a-是a的内逆;其次引入右e-弱群逆和右m-e-弱群逆的概念,给出了右m-e-弱群逆与右e-弱群逆之间的关系,并借助幂... 首先在^(*)-环上给出了m-e弱群逆存在的充分必要条件,作为应用证明了正则元a是(m+1)-e-弱群逆当且仅当a2a-是m-e弱群逆的,其中a-是a的内逆;其次引入右e-弱群逆和右m-e-弱群逆的概念,给出了右m-e-弱群逆与右e-弱群逆之间的关系,并借助幂等元研究了右m-e-弱群逆存在性的等价刻画。 展开更多
关键词 m-e-弱群逆 右e-弱群逆 右m-e-弱群逆
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偶超八面体群上左弱序的一个等价刻画
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作者 宝显婷 喻厚义 《西北师范大学学报(自然科学版)》 2025年第2期40-44,共5页
利用偶符号排列的逆序集与负和对集,给出了偶超八面体群上左弱序的一个等价刻画.作为应用,证明了给定负指标集的所有偶符号排列的集合在左弱序下是一个区间.
关键词 偶符号排列 左弱序 区间 偶超八面体群
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群体博弈的弱Nash平衡与演化分析
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作者 汤卫 王春 +1 位作者 杨光惠 皮进修 《运筹学学报(中英文)》 北大核心 2025年第4期112-120,共9页
在博弈的策略转移过程中,如果局中人会获得策略转移成本,那么一些局中人的最优回应策略可能没有最大化支付。对此,本文在群体博弈模型下引入更一般的策略转移成本函数,对弱Nash平衡概念进行改进,新的弱Nash平衡包含Nash平衡集。此外,我... 在博弈的策略转移过程中,如果局中人会获得策略转移成本,那么一些局中人的最优回应策略可能没有最大化支付。对此,本文在群体博弈模型下引入更一般的策略转移成本函数,对弱Nash平衡概念进行改进,新的弱Nash平衡包含Nash平衡集。此外,我们在2×2对称矩阵博弈诱导的单群体博弈下,通过复制动力学得到了弱Nash平衡稳定性,并进行了仿真实验。结果表明,相比未考虑策略转移成本的情形,演化稳定状态有所增加。 展开更多
关键词 策略转移成本 群体博弈 弱Nash平衡 复制动力学 演化稳定状态
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浅析集团公司对子公司的财务管理与控制
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作者 程海梅 《市场周刊》 2025年第26期115-118,共4页
集团公司对子公司的财务管理控制是集团公司顺利实现集团战略目标、防范财务风险、提高集团整体财务绩效、增强集团内部治理水平的有效手段。文章通过深入分析,指出集团公司应增强对子公司的财务管理控制意识,制定完善的财务管理控制措... 集团公司对子公司的财务管理控制是集团公司顺利实现集团战略目标、防范财务风险、提高集团整体财务绩效、增强集团内部治理水平的有效手段。文章通过深入分析,指出集团公司应增强对子公司的财务管理控制意识,制定完善的财务管理控制措施,提高集团公司对子公司的财务管理控制水平,进而顺利实现集团整体战略目标,推动集团及子公司的健康、有序发展。 展开更多
关键词 集团公司 子公司 财务管理控制 监督薄弱 信息共享
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可数离散群顺从性的算子代数等价刻画
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作者 方少明 张辉 《咸阳师范学院学报》 2025年第6期12-16,共5页
对于可数离散群顺从性的算子代数等价刻画,核心在于建立群表示的弱包含性质、约化群C^(*)-代数的结构特征与群顺从性之间的深刻联系。首先,基于弱包含的严格定义,揭示了左正则表示与平凡表示的弱包含关系对顺从性的刻画作用。其次,通过... 对于可数离散群顺从性的算子代数等价刻画,核心在于建立群表示的弱包含性质、约化群C^(*)-代数的结构特征与群顺从性之间的深刻联系。首先,基于弱包含的严格定义,揭示了左正则表示与平凡表示的弱包含关系对顺从性的刻画作用。其次,通过详细阐述并应用Hulanicki定理,证明约化群C^(*)-代数与全群C^(*)-代数的同构等价于群的顺从性。最后,深入讨论了nuclear C^(*)-代数的结构特征,完善补充并修正了John Roe关于“一个可数离散群G是顺从群当且仅当它的约化群C^(*)-代数C_(r)^(*)是nuclear C^(*)-代数”定理证明中的关键步骤与疏漏。文中结论不仅将经典结果整合为基于算子代数的统一框架,而且完善了若干核心定理的证明细节,为顺从群的研究提供了坚实的算子代数理论基础。 展开更多
关键词 顺从群 算子代数 群C^(*)-代数 nuclear C^(*)-代数 弱包含
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湖南省城镇“弱势群体”健康及健身状况的调查研究 被引量:12
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作者 谭志刚 贺仕刚 +1 位作者 陈勇 徐斌 《成都体育学院学报》 CSSCI 北大核心 2002年第6期20-22,共3页
对湖南省城镇弱势群体参加健身活动和身体健康现状进行抽样调查。结果显示 :城镇弱势群体的健康状况极差 ,健身意识不强、健身活动太少是其主要原因。提出了强化对弱势群体的救助和关注 ,不能仅限于生活上的关心 ,经济上的资助 ,还应关... 对湖南省城镇弱势群体参加健身活动和身体健康现状进行抽样调查。结果显示 :城镇弱势群体的健康状况极差 ,健身意识不强、健身活动太少是其主要原因。提出了强化对弱势群体的救助和关注 ,不能仅限于生活上的关心 ,经济上的资助 ,还应关心他们的体质与健康 ,支持他们参与健身活动。 展开更多
关键词 湖南 弱势群体 健身状况 调查研究 城镇居民 健康状况 全民健身
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