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Some Studies on Quasi AP-injective Modules 被引量:6
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作者 赵玉娥 杜先能 《Northeastern Mathematical Journal》 CSCD 2006年第1期73-80,共8页
Let R be a ring. R is called right AP-injective if, for any a E R, there exists a left ideal of R such that lr(a) = Ra+Xa. We extend this notion to modules. A right R-module M with S = End(MR) is called quasi AP-... Let R be a ring. R is called right AP-injective if, for any a E R, there exists a left ideal of R such that lr(a) = Ra+Xa. We extend this notion to modules. A right R-module M with S = End(MR) is called quasi AP-injective if, for any s∈S, there exists a left ideal Xs of S such that ls(Ker(s)) = Ss+Xs. In this paper, we give some characterizations and properties of quasi AP-injective modules which generalize results of Page and Zhou. 展开更多
关键词 quasi ap-injective module ap-injective ring self-generator ANNIHILATOR
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Some Notes on Quasi AP-injective Modules
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作者 赵玉娥 杜先能 《Northeastern Mathematical Journal》 CSCD 2006年第4期433-440,共8页
Let R be a ring. A right R-module M with S = End(MR) is called a quasi AP-injective module, if, for any s C S, there exists a left ideal Xs of S such that ls(ker s) = Ss+Xs. Let M be a quasi AP-injective module w... Let R be a ring. A right R-module M with S = End(MR) is called a quasi AP-injective module, if, for any s C S, there exists a left ideal Xs of S such that ls(ker s) = Ss+Xs. Let M be a quasi AP-injective module which is a self-generator. We show that for such a module, if S is semiprime, then every maximal kernel of S is a direct summand of M. Furthermore, if ker(a1) lohtain in ker(a2a1) lohtain in ker(a3a2a1) lohtain in... satisfy the ascending conditions for any sequence al, a2, a3,… ∈ S, then S is right perfect. In this paper, we give a series of results which extend and generalize results on AP-injective rings. 展开更多
关键词 quasi ap-injective module ap-injective ring self-generator
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On minimal quasi-injective modules and strong Kasch modules 被引量:2
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作者 朱占敏 张小向 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2009年第3期243-248,253,共7页
设R为一个环,M为一个右R-模.若每个从M的单子模到M的同态都可以开拓为M的自同态,则称M为一个极小拟内射模.若每个单的右R-模都可以嵌入M,则称M为一个强Kasch模.本文研究了这两类模的一些刻画和性质.
关键词 极小拟内射模 强Kasch模 半完全环 半局部环
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STUDY OF FAILURE MODES OF MICROELECTRONIC PACKAGING MODULES BY HOLOGRAPHY QUASI PROJECTION MOIRE METHOD 被引量:1
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作者 史训清 刘宝琛 戴福隆 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1997年第2期179-185,共7页
In this paper, a novel interferometric method with a wide range of sensitivities, called holography quasi projection moire, is proposed. It combines the features of the variated double projection moire method and the ... In this paper, a novel interferometric method with a wide range of sensitivities, called holography quasi projection moire, is proposed. It combines the features of the variated double projection moire method and the holographic interferometry method. This technique is used to study the failure modes of microelectronic packaging modules. 展开更多
关键词 HOLOGRAPHY quasi projection moire sensitivity failure modes packaging modules
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Characterization of V-modules by Relative Quasi-continuity
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作者 刘仲奎 《Northeastern Mathematical Journal》 CSCD 2001年第2期151-158,共8页
We characterize V modules by relative (quasi )continuity of left R modules in this paper. It is shown that a left R module M is a V module if and only if every finitely cogenerated left R ... We characterize V modules by relative (quasi )continuity of left R modules in this paper. It is shown that a left R module M is a V module if and only if every finitely cogenerated left R module in σ[M] is S ( quasi )continuous if and only if every left R module in σ[M] is S continuous, where S is the set of all simple left R modules. We also show that a left R module M is a locally noetherian V module if and only if every semisimple left R module (in σ[M]) is M injective if and only if every essential extension in σ[M] of every semisimple left R module in σ[M] is S ? 2 (quasi )continuous, where S ? 2 is the set of all semisimple left R modules. 展开更多
关键词 V module S continuous module S quasi continuous module
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Modulation of the Intensity of Nascent Tibetan Plateau Vortices by Atmospheric Quasi-Biweekly Oscillation 被引量:1
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作者 Lun LI Renhe ZHANG +1 位作者 Min WEN Jianping DUAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第11期1347-1361,共15页
The modulation of the intensity of nascent Tibetan Plateau vortices(ITPV) by atmospheric quasi-biweekly oscillation(QBWO) is investigated based on final operational global analysis data from the National Centers for E... The modulation of the intensity of nascent Tibetan Plateau vortices(ITPV) by atmospheric quasi-biweekly oscillation(QBWO) is investigated based on final operational global analysis data from the National Centers for Environmental Prediction. The spatial and temporal distributions of the ITPV show distinct features of 10–20-day QBWO. The average ITPV is much higher in the positive phases than in the negative phases, and the number of strong TPVs is much larger in the former,with a peak that appears in phase 3. In addition, the maximum centers of the ITPV stretch eastward in the positive phases,indicating periodic variations in the locations where strong TPVs are generated. The large-scale circulations and related thermodynamic fields are discussed to investigate the mechanism by which the 10–20-day QBWO modulates the ITPV. The atmospheric circulations and heating fields of the 10–20-day QBWO have a major impact on the ITPV. In the positive QBWO phases, the anomalous convergence at 500 hPa and divergence at 200 hPa are conducive to ascending motion. In addition, the convergence centers of the water vapor and the atmospheric unstable stratification are found in the positive QBWO phases and move eastward. Correspondingly, condensational latent heat is released and shifts eastward with the heating centers located at 400 hPa, which favors a higher ITPV by depressing the isobaric surface at 500 hPa. All of the dynamic and thermodynamic conditions in the positive QBWO phases are conducive to the generation of stronger TPVs and their eastward expansion. 展开更多
关键词 quasi-biweekly oscillation TIBETAN PLATEAU vortex modulATION
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The characterization of Γ-modules in terms of fuzzy soft Γ-submodules 被引量:1
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作者 ZHOU Min XIANG Da-jing ZHAN Jian-ming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第2期217-239,共23页
In this paper,we focus on combining the theories of fuzzy soft sets with Γ-modules,and establishing a new framework for fuzzy soft Γ-submodules.The main contributions of the paper are 3-fold.First,we present the con... In this paper,we focus on combining the theories of fuzzy soft sets with Γ-modules,and establishing a new framework for fuzzy soft Γ-submodules.The main contributions of the paper are 3-fold.First,we present the concepts of(R,S)-bi-Γ-submodules,quasi-Γ-submodules and regular Γ-modules.Meanwhile,some illustrative examples are given to show the rationality of the definitions introduced in this paper.Second,several new kinds of generalized fuzzy soft Γ-submodules are proposed,and related properties and mutual relationships are also investigated.Third,we discover some intrinsic connections between the generalized fuzzy soft Γ-submodules presented in this paper and crisp Γ-submodules,and describe the relationships between regular Γ-modules and the generalized fuzzy soft Γ-submodules presented in this paper. 展开更多
关键词 Fuzzy soft set Γ-module (∈ γ γ q δ)(resp. (■ γ γ δ))-fuzzy soft left R-Γ-submodule(right R-Γ-submodules (R S)-bi-Γ-submodule quasi-Γ-submodule) regular Γ-module
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Penrose Transform on Induced <i>D<sub>G/H</sub></i>-Modules and Their Moduli Stacks in the Field Theory
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作者 Francisco Bulnes 《Advances in Pure Mathematics》 2013年第2期246-253,共8页
We consider generalizations of the Radon-Schmid transform on coherent DG/H-Modules, with the intention of obtaining the equivalence between geometric objects (vector bundles) and algebraic objects (D-Modules) characte... We consider generalizations of the Radon-Schmid transform on coherent DG/H-Modules, with the intention of obtaining the equivalence between geometric objects (vector bundles) and algebraic objects (D-Modules) characterizing conformal classes in the space-time that determine a space moduli [1] on coherent sheaves for the securing solutions in field theory [2]. In a major context, elements of derived categories like D-branes and heterotic strings are considered, and using the geometric Langlands program, a moduli space is obtained of equivalence between certain geometrical pictures (non-conformal world sheets [3]) and physical stacks (derived sheaves), that establishes equivalence between certain theories of super symmetries of field of a Penrose transform that generalizes the implications given by the Langlands program. With it we obtain extensions of a cohomology of integrals for a major class of field equations to corresponding Hecke category. 展开更多
关键词 Penrose Transform Coherent G-quasi-Equivariant D-modules HECKE SHEAF modulI STACKS modulI Spaces
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功率前馈的准Z源光伏并网逆变器Quasi-PR控制 被引量:17
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作者 杜强 高锋阳 +2 位作者 乔垚 强国栋 庄圣贤 《高电压技术》 EI CAS CSCD 北大核心 2017年第10期3322-3329,共8页
为了加快准Z源光伏并网逆变器的动态响应,避免电网电压矢量定向控制策略需解耦控制和多次坐标变换的不足,同时提高并网电流控制器对电网频率偏移的适应范围,将功率前馈及准比例谐振控制引入准Z源光伏并网系统中。在两相静止坐标下,将功... 为了加快准Z源光伏并网逆变器的动态响应,避免电网电压矢量定向控制策略需解耦控制和多次坐标变换的不足,同时提高并网电流控制器对电网频率偏移的适应范围,将功率前馈及准比例谐振控制引入准Z源光伏并网系统中。在两相静止坐标下,将功率前馈、准比例谐振控制与直通分段空间矢量脉宽调制(SVPWM)相结合,设计了并网系统的完整控制策略。在Matlab/Simulink中搭建了系统仿真模型,并与传统控制进行对比分析。仿真结果表明:当外界环境发生变化时,采用功率前馈的准比例谐振控制策略能使系统较快地过渡到另一个稳态,且可实现对给定值的无静差跟踪控制,抗电网频率偏移能力强。 展开更多
关键词 光伏并网 准Z源逆变器 功率前馈 准比例谐振 直通分段空间矢量脉宽调制
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开关电感型Quasi-Z源逆变器SVPWM调制策略仿真研究 被引量:2
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作者 吴晓迪 梁占红 陶瑞 《电源技术》 CAS CSCD 北大核心 2014年第5期924-926,929,共4页
针对开关电感型Quasi-Z源逆变器,采用Matlab/Simulink仿真平台对空间矢量脉宽调制(SVPWM)策略进行了仿真研究。仿真结果表明,与简单升压调制策略相比,SVPWM调制策略具有开关频率低、直流母线电压小、调制度较大等优点,可以提高直流母线... 针对开关电感型Quasi-Z源逆变器,采用Matlab/Simulink仿真平台对空间矢量脉宽调制(SVPWM)策略进行了仿真研究。仿真结果表明,与简单升压调制策略相比,SVPWM调制策略具有开关频率低、直流母线电压小、调制度较大等优点,可以提高直流母线电压的利用率。 展开更多
关键词 开关电感型quasi-Z源逆变器 空间矢量脉宽调制 逆变器 简单升压调制
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开关电感Quasi-Z源逆变器SVPWM策略研究
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作者 吴晓迪 高金峰 +2 位作者 陶瑞 刘青 张锐 《电气传动》 北大核心 2013年第12期28-32,共5页
开关电感Quasi-Z源逆变器具有无源器件个数少,电感、二极管电流低等特点。将SVPWM调制策略应用于开关电感Quasi-Z源逆变器,实现电源的逆变。在对调制过程分析的基础上,通过调整同一桥臂的开关管开通、关断时刻,实现直通的插入,分别采用... 开关电感Quasi-Z源逆变器具有无源器件个数少,电感、二极管电流低等特点。将SVPWM调制策略应用于开关电感Quasi-Z源逆变器,实现电源的逆变。在对调制过程分析的基础上,通过调整同一桥臂的开关管开通、关断时刻,实现直通的插入,分别采用4次、6次和8次直通插入方式,对开关电感Quasi-Z源逆变器进行控制。通过分析可得,在低频情况下,直通次数越多,电感电流脉动越小,电气应力比较低;而在高频情况下,直通次数的多少将不会引起效果的明显差异。 展开更多
关键词 逆变器 开关电感quasi-Z源逆变器 空间矢量脉宽调制
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S-Armendariz模与Quasi S-Armendariz模
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作者 欧阳伦群 《数学物理学报(A辑)》 CSCD 北大核心 2010年第3期828-834,共7页
作为对Armendariz环的推广,该文引进了S-Armendariz模,并证明了S-Armendariz模具有许多与Armendariz环相类似的性质,从而将文献中的相关结论推广到更一般的情形.
关键词 Armendariz模 quasi Armendariz模 广义幂级数
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Quasi-dual模和V-环的一个新的推广(英文) 被引量:1
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作者 郭勇华 易忠 《广西师范大学学报(自然科学版)》 CAS 北大核心 2005年第3期33-37,共5页
定义了quasi-dual模,讨论了它的性质和等价条件,并且通过quasi-dual模,详细讨论了V-环的一个新的推广结构,得到了以下等价条件:1R/Soc(RR)是右V-环;2每一个R的本质真右理想是极大右理想的交;3存在一个奇异半单右R-模是quasi-dual的.
关键词 quasi-dual环 V-环 零化子 奇异模
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分次Quasi-内射模和分次Quasi-投射模
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作者 汤建良 黄留佳 易忠 《广西师范大学学报(自然科学版)》 CAS 2000年第1期42-45,共4页
设G是一个群 ,R是一个G 分次环 研究分次quasi 内射模 ,分次quasi 投射模分别与quasi 内射模和quasi 投射模的关系 特别地 。
关键词 quasi-内射模 分次quasi-投射模 模论
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PWAM控制的Quasi-Z源电机驱动系统
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作者 李艺 梁伟华 +1 位作者 郭明珠 葛宝明 《电源学报》 CSCD 北大核心 2018年第5期89-97,共9页
针对传统的quasi-Z源电机驱动系统效率低、体积大等缺点,提出了一种新型的脉冲宽度幅值调制PWAM(pulse-width-amplitude-modulation)方法。与其他广泛应用于电机驱动系统中的PWM方法有很大不同,该调制方法中每个调制周期内只有一个桥臂... 针对传统的quasi-Z源电机驱动系统效率低、体积大等缺点,提出了一种新型的脉冲宽度幅值调制PWAM(pulse-width-amplitude-modulation)方法。与其他广泛应用于电机驱动系统中的PWM方法有很大不同,该调制方法中每个调制周期内只有一个桥臂的上下开关管进行PWM的开关动作。因此,整个逆变器的开关动作和开关损耗大大减少,电机驱动系统的效率也随之提高;与传统PWM方法相比,混合调制方法所需的电感、电容明显减小,这使得系统的体积减小,经济性更强。通过建立1 k W的quasi-Z源逆变器仿真模型,其仿真结果验证了基于PWAM的磁场定向控制的永磁同步电机具有良好的运行结果。 展开更多
关键词 脉冲宽度幅值调制 quasi-Z源逆变器 磁场定向控制 电机驱动
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Baer、quasi-Baer和p.q.-Baer模
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作者 景丽敏 任艳丽 《南京晓庄学院学报》 2007年第6期4-6,共3页
文章定义了Baer模、quasi-Baer模和p.q.-Baer模.使用了环论和模论的一般方法,讨论了在一定条件下模的子模、商模、直积(直和)和同态象保Baer性(quasi-Bear性、p.q.-Baer性.)
关键词 Baer模 quasi-Baer模 p.q.-Baer模 直和项 模同态
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Quasi-α-斜线性Armendariz模
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作者 章东青 殷晓斌 《南通大学学报(自然科学版)》 CAS 2016年第4期80-86,共7页
作为线性Armendariz模和α-斜Armendariz模的推广,引入了quasi-α-斜线性Armendariz模的概念.研究了quasi-α-斜线性Armendariz模的若干性质,讨论了quasi-α-斜线性Armendariz模与其他模之间的关系,并给出了quasi-α-斜线性Armendariz... 作为线性Armendariz模和α-斜Armendariz模的推广,引入了quasi-α-斜线性Armendariz模的概念.研究了quasi-α-斜线性Armendariz模的若干性质,讨论了quasi-α-斜线性Armendariz模与其他模之间的关系,并给出了quasi-α-斜线性Armendariz模的平凡扩张. 展开更多
关键词 Armendariz模 α-斜Armendariz模 线性Armendariz模 quasi-α-斜线性Armendariz模 quasi-线性Armendariz模
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Design of Irregular QC-LDPC Code Based Multi-Level Coded Modulation Scheme for High Speed Optical Communication Systems 被引量:7
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作者 Liqian Wang Dongdong Wang +3 位作者 Yongjing Ni Xue Chen Midou Cui Fu Yang 《China Communications》 SCIE CSCD 2019年第5期106-120,共15页
In this paper, we focus on the design of irregular QC-LDPC code based multi-level coded modulation(MLCM) scheme by jointly optimizing the component code rate and the degree distribution of the irregular QC-LDPC compon... In this paper, we focus on the design of irregular QC-LDPC code based multi-level coded modulation(MLCM) scheme by jointly optimizing the component code rate and the degree distribution of the irregular QC-LDPC component code. Firstly, the sub-channel capacities of MLCM systems is analyzed and discussed, based on which the optimal component code rate can be obtained. Secondly, an extrinsic information transfer chart based two-stage searching algorithm is proposed to find the good irregular QC-LDPC code ensembles with optimal component code rates for their corresponding sub-channels. Finally, by constructing the irregular QC-LDPC component codes from the designed ensembles with the aim of possibly enlarging the girth and reducing the number of the shortest cycles, the designed irregular QC-LDPC code based 16QAM and 64QAM MLCM systems can achieve 0.4 dB and 1.2 dB net coding gain, respectively, compared with the recently proposed regular QC-LDPC code based 16QAM and 64QAM MLCM systems. 展开更多
关键词 quasi-cyclic LOW-DENSITY parity check (QC-LDPC) code irregular extrinsic INFORMATION transfer(EXIT) chart generalized mutual information(GMI) MULTI-LEVEL coded modulation(MLCM)
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On Quasi-Chebyshevity Subsets of Unital Banach Algebras
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作者 M.Iranmanesh F.Soleimany 《Analysis in Theory and Applications》 CSCD 2018年第1期92-102,共11页
In this paper, first, we consider closed convex and bounded subsets of infinite-dimensional unital Banach algebras and show with regard to the general conditions that these sets are not quasi-Chebyshev and pseudo-Cheb... In this paper, first, we consider closed convex and bounded subsets of infinite-dimensional unital Banach algebras and show with regard to the general conditions that these sets are not quasi-Chebyshev and pseudo-Chebyshev. Examples of those algebras are given including the algebras of continuous functions on compact sets. We also see some results in C*-algebras and Hilbert C*-modules. Next, by considering some conditions, we study Chebyshev of subalgebras in C*-algebras. 展开更多
关键词 Best approximation quasi-Chebyshev sets Pseudo-Chebyshev C*-algebras HilbertC*-modules.
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准二维钙钛矿中结晶调控与低阈值微纳激光器
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作者 高华兴 张红旗 李璇 《材料导报》 EI CAS CSCD 北大核心 2024年第12期22-26,共5页
准二维(Q-2D)钙钛矿由于大的激子结合能和量子限域作用,是一种可以应用于光电器件构筑的有前途的材料。然而,Q-2D钙钛矿是具有丰富晶界和界面的多相结构,在能量传递过程中导致非辐射损耗。本工作通过操纵不同n相的结晶动力学过程,实现了... 准二维(Q-2D)钙钛矿由于大的激子结合能和量子限域作用,是一种可以应用于光电器件构筑的有前途的材料。然而,Q-2D钙钛矿是具有丰富晶界和界面的多相结构,在能量传递过程中导致非辐射损耗。本工作通过操纵不同n相的结晶动力学过程,实现了Q-2D钙钛矿中更高效的能量传递。通过在Q-2D钙钛矿前驱体中引入钠离子来实现对Q-2D钙钛矿成核和生长过程的操控。研究表明,钠离子的掺入促进高n相的成核,使不同n相在空间上更均匀地分布,寿命的表征证实该操作促进了能量的转移。得益于这种高效的能量传递过程,与普通薄膜体系的光放大阈值(23.3μJ·cm^(-2))相比,掺杂薄膜的光放大阈值降低至14.3μJ·cm^(-2)。该研究提供了一种有效的优化Q-2D钙钛矿光子学性能的新方法,从而进一步拓宽Q-2D钙钛矿的光子学应用范围。 展开更多
关键词 准二维钙钛矿 Na+掺杂 结晶调控 能量传递 微纳激光器
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