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有限置换模自同态环的可分性质 被引量:1
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作者 陈焕艮 《数学年刊(A辑)》 CSCD 北大核心 2003年第4期521-528,共8页
设Q是有限置换右R模,则End_R(Q)是可分环当且仅当对所有A,B∈FP(Q),A AA B B B A≤ B或 B≤A,作为应用得到了 End_R(P Q)是可分环当且仅当End_R P和End_R Q为可分环,其中P,Q为有限置换右R模。
关键词 可分环 有限置换性模 自同态
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关于2可逆的置换可分环(英文)
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作者 陈焕银 《数学进展》 CSCD 北大核心 2017年第4期563-569,共7页
环R称为可分环,如果对任何有限生成投射右R-模A和B,AA≌AB≌BBA≌B.假设R是置换可分环,其中2可逆,a-a^3∈R正则,证明了a∈R单位正则当且仅当R(1-a^2)R=Rr(a)=e(a)R.环R中元素a称为特殊clean元,如果有幂等元e∈R使得a-e∈R可逆,... 环R称为可分环,如果对任何有限生成投射右R-模A和B,AA≌AB≌BBA≌B.假设R是置换可分环,其中2可逆,a-a^3∈R正则,证明了a∈R单位正则当且仅当R(1-a^2)R=Rr(a)=e(a)R.环R中元素a称为特殊clean元,如果有幂等元e∈R使得a-e∈R可逆,而且aR∩eR=0.进一步,证明了a∈R是特殊clean元,如果aR/ar(a^2),R/(aR+r(a))投射,而且R(a-a^3)R=Rar(a^2)=e(a^2)aR.由此推广了正则可分环中相关结论. 展开更多
关键词 单位正则元 特殊clean元 可分环 置换
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模一个诣零理想的可分性的提升
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作者 裴银淑 《鞍山师范学院学报》 2002年第3期25-27,共3页
一个环称为可分的 ,如果它的扭理想是直和项 .本文研究可分环模一个诣零理想的提升问题 .证明了如果环R满足条件 :对任意a∈R ,若存在幂等元e和 f,使得 (1-e)a(1-f) =0 且R模一个诣零理想后是可除理想与扭理想的和 。
关键词 谐零理想 提升 可分 扭理想 可除理想 可分环 直和项
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上环的若干性质在其对偶中的推广 被引量:3
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作者 江静 王顶国 《曲阜师范大学学报(自然科学版)》 CAS 2007年第1期17-22,共6页
在Brzezinski T(2002)A-上环的基础上介绍了C-环的基本概念,C是一个余代数.分析了C-环及其模范畴的结构,并构造了C-环的例子.研究了C-环中的两个主要函子:忘却函子F:MA→MC和导出函子-□CA:MC→MA.并且讨论了两个函子可分的条件以及这... 在Brzezinski T(2002)A-上环的基础上介绍了C-环的基本概念,C是一个余代数.分析了C-环及其模范畴的结构,并构造了C-环的例子.研究了C-环中的两个主要函子:忘却函子F:MA→MC和导出函子-□CA:MC→MA.并且讨论了两个函子可分的条件以及这两个函子的伴随情况.其次结合伽罗华理论将上环的一些主要性质推广到C-环,进而得到了C-环中的一些有意义的结论. 展开更多
关键词 A-上 C- 伽罗华C- 可分C-
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数学年刊第26卷B辑第1期(2005)目次和提要
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《数学年刊(A辑)》 CSCD 北大核心 2005年第1期i001-i002,共2页
关键词 维数 半定松弛 正则性 年刊 连续出版物 可分环 方程组 联立方程 函数族 拟对称 核空间 线性空间 数学 局部适定性 范数 泛函 消去 提要 二次文献 目次
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EFFICIENT METHOD FOR MULTIDISCIPLINARY DESIGN OPTIMIZATION BY CONSIDERING UNCERTAINTY
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作者 贺谦 李元生 +2 位作者 敖良波 温志勋 岳珠峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第3期213-218,共6页
A new reliability-based multidisciplinary design optimization (RBMDO) framework is proposed by combining the single-loop-based reliability analysis (SLBRA) method with multidisciplinary feasible (MDF) method. Th... A new reliability-based multidisciplinary design optimization (RBMDO) framework is proposed by combining the single-loop-based reliability analysis (SLBRA) method with multidisciplinary feasible (MDF) method. The Kriging approximate model with updating is introduced to reduce the computational cost of MDF caused by the complex structure. The computational efficiency is remarkably improved as the lack of iterative process during reliability analysis. Special attention is paid to a turbine blade design optimization by adopting the proposed method. Results show that the method is much more efficient than the commonly used double-loop based RBMDO method. It is feasible and efficient to apply the method to the engineering design. 展开更多
关键词 multidisciplinary design optimization multidisciplinary feasible method single loop method reliability analysis Kriging approximate model
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ANALYSIS ON A TYPE OF SERVICING MACHINES MODEL WITH REPAIRABLE SERVICE STATION
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作者 朱翼隽 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第2期153-159,共7页
This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantiti... This paper deals with a type of servicing machines model, which service station has a life time of the kth Er-langian distribution and can be repaired just like a new one. The cyclic time and the inefficiency quantities of this system in equilibrium are obtained. 展开更多
关键词 queuing theory DISTRIBUTION Erlangian distribution repairable service station cyclic time inefficiency quantities
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The Least Distributive Lattice Congruence on Commutative Distributive Semiring 被引量:7
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作者 LI Shi-zheng,LI Shan-hai,YU Xiao-ming (Department of Mathematics, Shandong Normal University, Shandong 250014,China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第1期35-43,共9页
In this paper, we describe the least distributive lattice congruence on a commutative distributive semiring.
关键词 SEMIRING commutative distributive semiring distributive lattice congruence
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Generalized Multi-component TC Hierarchy and Its Multi-component Integrable Coupling System 被引量:1
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作者 XIA Tie-Cheng YOU Fu-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5X期793-798,共6页
A new 3M-dimensional Lie algebra X is constructed firstly. Then, the corresponding loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1.... A new 3M-dimensional Lie algebra X is constructed firstly. Then, the corresponding loop algebra X is produced, whose commutation operation defined by us is as simple and straightforward as that in the loop algebra A1.It follows that a generalscheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then well-known multi-component TC hierarchy is obtained. Finally,an expanding loop algebra FM of the loop algebra X is presented. Based on the FM, the multi-component integrable coupling system of the generalized multi-component TC hierarchy has been worked out. The method in this paper can be applied to other nonlinear evolution equations hierarchies. It is easy to find that we can construct any finite-dimensional Lie algebra by this approach. 展开更多
关键词 loop algebra multi-component TC hierarchy multi-component integrable coupling system
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A New Loop Algebra and Its Corresponding Multi-component Integrable Hierarchy
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作者 YAO Yu-Qin CHEN Deng-Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期385-388,共4页
A type of new loop algebra GM is constructed by making use of the concept of cycled numbers. As its application, an isospectral problem is designed and a new multi-component integrable hierarchy with multi-potential f... A type of new loop algebra GM is constructed by making use of the concept of cycled numbers. As its application, an isospectral problem is designed and a new multi-component integrable hierarchy with multi-potential functions is worked out, which can be reduced to the famous KN hierarchy. 展开更多
关键词 cycled numbers loop algebra multi-component integrable hierarchy
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New Matrix Loop Algebra and Its Application
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作者 DONG Huan-He XU Yue-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期321-325,共5页
A new matrix Lie algebra and its corresponding Loop algebra are constructed firstly,as its application,the multi-component TC equation hierarchy is obtained,then by use of trace identity the Hamiltonian structure of t... A new matrix Lie algebra and its corresponding Loop algebra are constructed firstly,as its application,the multi-component TC equation hierarchy is obtained,then by use of trace identity the Hamiltonian structure of the above system is presented.Finally,the integrable couplings of the obtained system is worked out by the expanding matrix Loop algebra. 展开更多
关键词 matrix loop algebra Liouville integrable system Hamiltonian structure integrable couplings
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Carbon Productivity Analysis to Address Global Climate Change 被引量:5
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作者 He Jiankun Su Mingshan 《Chinese Journal of Population,Resources and Environment》 2011年第1期9-15,共7页
Developing low-carbon economy and enhancing carbon productivity are basic approaches to coordinating economic development and protecting global environment, which are also the major ways to address climate change unde... Developing low-carbon economy and enhancing carbon productivity are basic approaches to coordinating economic development and protecting global environment, which are also the major ways to address climate change under the framework of sustainable development. In this paper, the authors analyze the annual rate of carbon productivity growth, the differences of carbon productivity of different countries, and the factors for enhancing carbon productivity. Consequently, the authors clarify their viewpoint that the annual rate of carbon productivity growth can be used to weigh the efforts that a country takes to address climate change, and propose policies and suggestions on promoting carbon production. 展开更多
关键词 carbon productivity annual rate of carbon productivity growth global climate change greenhouse gas reduction
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Multi-component Levi Hierarchy and Its Multi-component Integrable Coupling System
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作者 XIA Tie-Cheng YOU Fu-Cai ZHAO Wen-Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期990-996,共7页
A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-... A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then by making use of the Tu scheme the well-known multi-component Levi hierarchy is obtained. Finally, an expanding loop algebra FM of the loop algebra .X is presented, based on the FM, the multi-component integrable coupling system of the multi-component Levi hierarchy is worked out. The method in this paper can be applied to other nonlinear evolution equation hierarchies. 展开更多
关键词 loop algebra multi-component Levi hierarchy multi-component integrable coupling system
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Study on Weed Control and Safety of Tembotrione-Atrazine Tank Mixture in Spring Maize Fields
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作者 SHAO Jia-li SUN Jin-jun DUAN Gui-fang 《Agricultural Science & Technology》 CAS 2022年第1期28-31,38,共5页
This study aimed to explore the effect of 5% tembotrione oil dispersion(OD)-38% atrazine suspension concentrate(SC) tank mixture on the weeds in spring maize fields and the safety of the mixture. To be specific, rando... This study aimed to explore the effect of 5% tembotrione oil dispersion(OD)-38% atrazine suspension concentrate(SC) tank mixture on the weeds in spring maize fields and the safety of the mixture. To be specific, randomized block design was adopted for the field experiments. The results showed that the application of tankmixture of 5% tembotrione OD at 90 g a.i./hm^(2)and 38% atrazine SC at 570 g a.i./hm^(2)and the mixture of 5% tembotrione OD at 90 g a.i./hm^(2)and 38% atrazine SC at 1140 g a.i./hm^(2)respectively controlled 94.7%~96.3% and 94.0%~96.3% of the grass weeds, 94.7%~96.0% and 93.7%~95.7% fresh weight of grass weeds, 95.3%~96.3%and 93.3%~97.3% of broadleaf weeds, and 94.7%~96.0% and 93.3%~96.3% fresh weight of broadleaf weeds. The efficacy was better than that of the 5% tembotrione alone and the control herbicide and no phytotoxicity of the mixtures was identified.The tank mixture of tembotrione and atrazine should be promoted in the spring maize field for weed control and the recommended dosages were 90 g a.i./hm^(2)for 5%tembotrione and 570 g a.i./hm^(2)for 38% atrazine. 展开更多
关键词 5%Tembotrione OD 38%Atrazine SC MAIZE Weed control Crop safety
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Educational Achievement, Age Distribution and the Disables
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作者 Jitesh Chandra Saha 《Management Studies》 2018年第5期414-424,共11页
Educational achievement and age correlatives may have significant bearings on generation, maintenance, and sustenance of environment to disseminate education for comprehensive development of learners as permeation of ... Educational achievement and age correlatives may have significant bearings on generation, maintenance, and sustenance of environment to disseminate education for comprehensive development of learners as permeation of learning and its diffusion rate may vary depending upon different achievements on literacy scale for different age groups. More so, for disable learners as such learners need additional initiatives and assisting environment of even more literate fellow beings constituting surroundings. From this perspective, this paper makes a descriptive analytical effort to present census (2011) results in evaluating overall literacy position and that for disable ones alongwith environment availability through simple statistical tools 展开更多
关键词 CENSUS LITERACY age composition educational environment disable learners
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High Cycle Fatigue Life Prediction and Reliability Analysis of Aeroengine Blades
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作者 张俊红 林杰威 +1 位作者 张桂昌 刘海 《Transactions of Tianjin University》 EI CAS 2012年第6期456-464,共9页
Based on the nonlinear continuum damage model (CDM) developed by Chaboehe, a modified model for high cycle fatigue of TC4 alloy was proposed. Unsymmetrical cycle fatigue tests were conducted on rod specimens at room... Based on the nonlinear continuum damage model (CDM) developed by Chaboehe, a modified model for high cycle fatigue of TC4 alloy was proposed. Unsymmetrical cycle fatigue tests were conducted on rod specimens at room temperature. Then the material parameters needed in the CDM were obtained by the fatigue tests, and the stress distribution of the specimen was calculated by FE method. Compared with the linear damage model (LDM), the dam- age results and the life prediction of the CDM show a better agreement with the test and they are more precise than the LDM. By applying the CDM developed in this study to the life prediction of aeroengine blades, it is concluded that the root is the most dangerous region of the whole blade and the shortest life is 58 211 cycles. Finally, the Cox propor- tional hazard model of survival analysis was applied to the analysis of the fatigue reliability. The Cox model takes the covariates into consideration, which include diameter, weight, mean stress and tensile strength. The result shows that the mean stress is the only factor that accelerates the fracture process. 展开更多
关键词 life prediction RELIABILITY continuum damage model survival analysis Cox proportional hazard model aeroengine blade
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Some Structures of Irreducible Polynomials over a Unique Factorization Domain R 被引量:4
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作者 王瑞 《Journal of Mathematical Research and Exposition》 CSCD 1999年第2期367-373,共7页
In this paper, we give the conception of implicit congruence and nonimplicit congruence in a unique factorization domain R and establish some structures of irreducible polynomials over R . A classical result, E... In this paper, we give the conception of implicit congruence and nonimplicit congruence in a unique factorization domain R and establish some structures of irreducible polynomials over R . A classical result, Eisenstein′s criterion, is generalized. 展开更多
关键词 unique factorization domain prime element nonimplicit congruence irreducible polynomial.
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CONSTRUCTION OF INDECOMPOSABLEDEFINITE HERMITIAN FORMS 被引量:2
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作者 ZHU FUZU (Department ofMathematics, East China Normal University Shanghai 200062,China) 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1994年第3期349-360,共12页
This Paper gives a method to construct indecomposable positive definite integral Hermitianforman imnginary quadratic field Q with gin discriminant and g。n rank.It is shown that for ally natural numbers n and a, there... This Paper gives a method to construct indecomposable positive definite integral Hermitianforman imnginary quadratic field Q with gin discriminant and g。n rank.It is shown that for ally natural numbers n and a, there are n-ary Indecomposable positivedefinite intopal Herlllltian lattices over Q(resp. Q)with discriminant a, exceptfor four(resp. one) exceptions. In these exceptional cases there are no lattices with the desiredproperties. 展开更多
关键词 Indecomposable lattice(form) Minimum of a lattice(form) Minimal、ctor Irreduclble vector.
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Limit Cycles Bifurcating from a Quadratic Reversible Lotka-Volterra System with a Center and Three Saddles 被引量:1
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作者 Kuilin WU Haihua LIANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第1期25-32,共8页
This paper is concerned with limit cycles which bifurcate from a period annulus of a quadratic reversible Lotka-Volterra system with sextic orbits.The authors apply the property of an extended complete Chebyshev syste... This paper is concerned with limit cycles which bifurcate from a period annulus of a quadratic reversible Lotka-Volterra system with sextic orbits.The authors apply the property of an extended complete Chebyshev system and prove that the cyclicity of the period annulus under quadratic perturbations is equal to two. 展开更多
关键词 Reversible Lotka-Volterra systems Abelian integrals Limit cycles
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A compact tunable metamaterial filter based on split-ring resonators 被引量:1
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作者 赵亚娟 周必成 +2 位作者 张泽奎 张榕 李宝毅 《Optoelectronics Letters》 EI 2017年第2期120-122,共3页
A tunable metamaterial filter is designed based on split-ring resonators(SRRs) in this paper. The metamaterial filter has a compact size of 15 mm×20 mm, and miniaturization is realized by using the SRRs. By loadi... A tunable metamaterial filter is designed based on split-ring resonators(SRRs) in this paper. The metamaterial filter has a compact size of 15 mm×20 mm, and miniaturization is realized by using the SRRs. By loading tunable devices, the continuous operation of the filter is realized at X band(from 10.7 GHz to 12 GHz), the bandwidth is about 13%, the minimum return loss is 35 dB, and the maximum insertion loss is 0.37 d B. The results illustrate that the metamaterial filter shows the compact size, wide bandwidth and good band pass characteristics. 展开更多
关键词 tunable bandwidth illustrate return realized split resonator insertion dielectric symmetrical
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