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n-strongly Gorenstein Projective and Injective and Flat Modules 被引量:3
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作者 YANG Xiao-yan 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第4期553-564,共12页
In this paper, we study some properties of n-strongly Gorenstein projective,injective and flat modules, and discuss some connections between n-strongly Gorenstein injective, projective and flat modules. Some applicati... In this paper, we study some properties of n-strongly Gorenstein projective,injective and flat modules, and discuss some connections between n-strongly Gorenstein injective, projective and flat modules. Some applications are given. 展开更多
关键词 n-strongly Gorenstein projective module n-strongly Gorenstein injective module n-strongly Gorenstein flat module
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Notes on Strongly n-Gorenstein Projective, Injective and Flat Modules 被引量:1
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作者 SHANG Wen-liang 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期389-396,共8页
In this paper, we mainly investigate some properties of strongly n-Gorenstein projective, injective and flat modules under the extension of rings, which mainly including excellent extensions, morita equivalences, poly... In this paper, we mainly investigate some properties of strongly n-Gorenstein projective, injective and flat modules under the extension of rings, which mainly including excellent extensions, morita equivalences, polynomial extensions and localizations. 展开更多
关键词 excellent extensions strongly n-Gorenstein projective modules strongly nGorenstein injective modules strongly n-Gorenstein flat modules
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A Generalization of Gorenstein Injective and Flat Modules
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作者 LU BO Du Xian-kun 《Communications in Mathematical Research》 CSCD 2016年第4期339-351,共13页
In this article, we introduce and study the concept of n-Gorenstein injective (resp., n-Gorenstein flat) modules as a nontrivial generalization of Gorenstein injective (resp., Gorenstein flat) modules. We invest... In this article, we introduce and study the concept of n-Gorenstein injective (resp., n-Gorenstein flat) modules as a nontrivial generalization of Gorenstein injective (resp., Gorenstein flat) modules. We investigate the properties of these modules in various ways. For example, we show that the class of n-Gorenstein injective (resp., n -Gorenstein flat) modules is closed under direct sums and direct products for n ≥ 2. To this end, we first introduce and study the notions of n-injective modules and n-flat modules. 展开更多
关键词 n-injective module n-flat module n-Gorenstein injective module n- Gorenstein flat module PREENVELOPE COVER
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PS-injective Modules, PS-flat Modules and PS-coherent Rings
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作者 Xiang Yue-ming Du Xian-kun 《Communications in Mathematical Research》 CSCD 2013年第2期121-130,共10页
A left ideal I of a ring R is small in case for every proper left ideal K of R, K + I ≠R. A ring R is called left PS-coherent if every principally small left ideal Ra is finitely presented. We develop, in this paper... A left ideal I of a ring R is small in case for every proper left ideal K of R, K + I ≠R. A ring R is called left PS-coherent if every principally small left ideal Ra is finitely presented. We develop, in this paper, PS-coherent rings as a generalization of P-coherent rings and J-coherent rings. To characterize PS-coherent rings, we first introduce PS-injective and PS-flat modules, and discuss the relation between them over some spacial rings. Some properties of left PS-coherent rings are also studied. 展开更多
关键词 PS-injective module PS-flat module PS-coherent ring
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ABSOLUTELY E-PURE MODULES AND E-PURE SPLIT MODULES 被引量:2
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作者 阎舫宇 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期207-220,共14页
We first introduce the concepts of absolutely E-pure modules and E-pure split modules. Then, we characterize the IF rings in terms of absolutely E-pure modules. The E-pure split modules are also characterized.
关键词 Absolutely E-pure module E-pure split module IF ring copure flat module
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Combining cytochrome P-450 3A4 modulators and cyclosporine or everolimus in transplantation is successful 被引量:4
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作者 Fernando González Ricardo Valjalo 《World Journal of Transplantation》 2015年第4期338-347,共10页
AIM: To describe the long term follow-up of kidney allograft recipients receiving ketoconazole with calcineurin inhibitors(CNI) alone or combined with everolimus. METHODS: This is an open-label, prospective observatio... AIM: To describe the long term follow-up of kidney allograft recipients receiving ketoconazole with calcineurin inhibitors(CNI) alone or combined with everolimus. METHODS: This is an open-label, prospective observational clinical trial in low immunologic risk patients who, after signing an Institutional Review Board approved consent form, were included in one of two groups. The first one(n = 59) received everolimus(target blood level, 3-8 ng/m L) and the other(n = 114) azathioprine 2 mg/kg per day or mycophenolate mofetyl(MMF) 2 g/d. Both groups also received tapering steroids, the cytochrome P-450 3A4(CYP3A4) modulator, ketoconazole 50-100 mg/d, and cyclosporine with C0 targets in the everolimus group of 200-250 ng/mL in 1 mo, 100-125 ng/m L in 2 mo, and 50-65 ng/m L thereafter, and in the azathioprine or MMF group of 250-300 ng/mL in 1 mo, 200-250 ng/mL in 2 mo, 180-200 ng/m L until 3-6 mo, and 100-125 ng/mL thereafter. Clinical visits were performed monthly the first year and quarterly thereafter by treating physicians and all data was extracted by the investigators.RESULTS: The clinical characteristics of these two cohorts were similar. During the follow up(66 + 31 mo), both groups showed comparable clinical courses, but the biopsy proven acute rejection rate during the full follow-up period seemed to be lower in the everolimus group(20% vs 36%; P = 0.04). The everolimus group did not show a higher surgical complication rate thanthe other group. By the end of the follow-up period, the everolimus group tended to show a higher glomerular filtration rate. Nevertheless, we found no evidence of a consistent negative slope of the temporal allograft function estimated by the modification of the diet in renal disease formula in any of both groups. At 6 years of follow-up, the uncensored and death-censored graft survivals were 91% and 93%, and 91% and 83% in the everolimus plus cyclosporine, and cyclosporine alone groups, respectively. The addition of ketoconazole saved 80% of cyclosporine and 56% of everolimus doses. CONCLUSION: Combining CYP3A4 modulators with CNI or mammalian target of rapamycin inhibitor, in low immunological risk kidney transplant recipients is feasible, effective, safe and affordable even in the long term. 展开更多
关键词 Kidney transplant IMMUNOSUPPRESSIVE CYCLOSPORINE KETOCONAZOLE EVEROLIMUS CYTOCHROME p-450 CYTOCHROME p-450 3A4 modulator
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IFP-FLAT DIMENSIONS AND IFP-INJECTIVE DIMENSIONS 被引量:1
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作者 卢博 刘仲奎 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2085-2095,共11页
In basic homological algebra, the flat and injective dimensions of modules play an important and fundamental role. In this paper, the closely related IFP-flat and IFP-injective dimensions are introduced and studied. W... In basic homological algebra, the flat and injective dimensions of modules play an important and fundamental role. In this paper, the closely related IFP-flat and IFP-injective dimensions are introduced and studied. We show that IFP-fd(M) = IFP-id(M+) and IFP-fd(M+)=IFP-id(M) for any R-module M over any ring R. Let :Z-In (resp., "Zgv,~) he the class of all left (resp., right) R-modules of IFP-injective (resp., IFP-flat) dimension at most n. We prove that every right R-module has an IFn- preenvelope, (IFn,IF⊥n) is a perfect cotorsion theory over any ring R, and for any ring R with IFP-id(RR) 〈 n, (IIn,II⊥n) is a perfect cotorsion theory. This generalizes and improves the earlier work (J. Algebra 242 (2001), 447-459). Finally, some applications are given. 展开更多
关键词 IFp-flat dimension IFp-injective dimension Pre (Cover) Pre (Envelope) Cotorsion theory IFp-cotorsion module
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Flatly Broadened and Highly Coherent Supercontinuum Generation by Induced Modulation Instability in ANDi-PCF
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作者 Chunfu Cheng Yan Zeng +2 位作者 Yiwen Ou Zhangyong Yang Zehao Chen 《Journal of Applied Mathematics and Physics》 2018年第4期640-646,共7页
In this paper, a flatly broadened and highly coherent supercontinuum generation by induced modulation instability in ANDi-PCF is proposed. The numerical results show that the bandwidth of supercontinuun can be increas... In this paper, a flatly broadened and highly coherent supercontinuum generation by induced modulation instability in ANDi-PCF is proposed. The numerical results show that the bandwidth of supercontinuun can be increased by increasing the modulation depth and the coherence property of supercontinuum can be improved with the optimal modulation frequency. A highly coherent supercontinuum with the 10 dB bandwidth of 1305 nm and the flatness of less than 10 dB can be obtained when seeding at the modulation depth of 0.3 and modulation frequency of 24 THz. 展开更多
关键词 SUPERCONTINUUM Generation flat COHERENT modulation INSTABILITY
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关于P-平坦模 被引量:14
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作者 李珊珊 汪明义 《广西师范大学学报(自然科学版)》 CAS 2004年第4期36-40,共5页
给出了P-平坦模的定义,并探讨了P-平坦模具有的一些良好性质,以及P-平坦模与平坦模等几类模之间的关系,最后用P-平坦模来刻画了几种常见的环.
关键词 p-平坦模 平坦模 p-内射模Von Neumann正则环 SF-环
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关于L P-内射模与L-P-平坦模 被引量:6
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作者 周德旭 《福建师范大学学报(自然科学版)》 CAS CSCD 1999年第3期16-21,共6页
引进LP内射模与LP平坦模的概念, 给出了它们的特征刻划, 并用这二类模刻划了LPcoherent环、LP正则环。
关键词 内射模 平坦模 右R模 R-P平坦模 R-P内射模
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关于ZP-内射维数及ZP-平坦维数 被引量:1
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作者 徐龙玉 万吉湘 王芳贵 《江西师范大学学报(自然科学版)》 CAS 北大核心 2016年第2期200-203,共4页
给出了ZP-内射维数以及ZP-平坦维数的定义,揭示了左ZP-内射维数l.zp.ID(R)=0及右ZP-平坦维数r.zp.FD(R)=0的环,即它们为非奇异环,并给出等价描述.讨论了环R的左ZP-内射维数l.zp.ID(R)≤n以及环R的右ZP-平坦维数r.zp.FD(R)≤n的等价刻画... 给出了ZP-内射维数以及ZP-平坦维数的定义,揭示了左ZP-内射维数l.zp.ID(R)=0及右ZP-平坦维数r.zp.FD(R)=0的环,即它们为非奇异环,并给出等价描述.讨论了环R的左ZP-内射维数l.zp.ID(R)≤n以及环R的右ZP-平坦维数r.zp.FD(R)≤n的等价刻画,证明了环R上的模类ZPI若满足单同态的上核封闭且l.zp.ID(R)<!,则l.zp.ID(R)=r.zp.FD(R)=l.zp-id(_RR),并证明ZP-内射左R-模的商模是ZP-内射模当且仅当模类ZPI满足单同态的上核封闭且l.zp.ID(R)≤1. 展开更多
关键词 Zp-内射模 Zp-内射维数 Zp-平坦模 Zp-平坦维数
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广义FP-内射模、广义平坦模与某些环 被引量:7
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作者 朱占敏 《数学理论与应用》 2002年第3期40-46,共7页
左(右)R-模A称为GFP-内射模,如果ExtR1(M,A)=0对任-2-表现R-模M成立;左(右)R-模称为G-平坦的,如果TorR1(M,A)=0(TorR1(AM)=0)对于任一2-表现右(左)R-模M成立;环R称左(右)G-半遗传环,如果投射左(右)R-模的有限表现子... 左(右)R-模A称为GFP-内射模,如果ExtR1(M,A)=0对任-2-表现R-模M成立;左(右)R-模称为G-平坦的,如果TorR1(M,A)=0(TorR1(AM)=0)对于任一2-表现右(左)R-模M成立;环R称左(右)G-半遗传环,如果投射左(右)R-模的有限表现子模是投射的;环R称为左(右)G-正则环,如果自由左(右)R-模的有限表现子模为其直和项.研究了GFP-内射模和G-平坦模的一些性质,给出了它们的一些等价刻划.并利用它们刻划了凝聚环、G-半遗传环和G-正则环. 展开更多
关键词 广义Fp-内射模 广义平坦模 G-平坦模 凝聚环 G-半遗传环 G-正则环
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关于内射模的P-平坦性 被引量:1
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作者 王修建 杜先能 《大学数学》 2011年第6期88-92,共5页
通过引用P-平坦模的定义,引入了右IPF环的概念,推广了右IF环的概念,这对研究IF环及QF环具有重要的作用,同时对右IPF环的性质作了一些刻画,得到了右IPF环的若干个等价命题;最后,用P-平坦模及右IPF环推出了正则环的一些等价条件.
关键词 右IPF环 p-平坦模 p-内射模 p-凝聚环 正则环
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关于ZP-凝聚环
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作者 徐龙玉 胡葵 +1 位作者 万吉湘 王芳贵 《四川师范大学学报(自然科学版)》 CAS 北大核心 2017年第1期68-72,共5页
给出ZP-凝聚环的概念,举例说明左ZP-凝聚环不一定是右ZP-凝聚环,并利用ZP-内射盖及ZP-平坦预包对ZP-凝聚环进行一系列的等价刻画,如R是左ZP-凝聚环,当且仅当ZP-平坦右R-模的直积是ZP-平坦右R-模,当且仅当任意右R-模有一个ZP-平坦预包.... 给出ZP-凝聚环的概念,举例说明左ZP-凝聚环不一定是右ZP-凝聚环,并利用ZP-内射盖及ZP-平坦预包对ZP-凝聚环进行一系列的等价刻画,如R是左ZP-凝聚环,当且仅当ZP-平坦右R-模的直积是ZP-平坦右R-模,当且仅当任意右R-模有一个ZP-平坦预包.证明左ZP-凝聚环上的任意左R-模存在ZP-内射盖,并揭示若R是左ZP-凝聚环,则RR是ZP-内射模,当且仅当任意左R-模有一个满的ZP-内射盖,当且仅当任意右R-模有一个单的ZP-平坦预包. 展开更多
关键词 Zp-凝聚环 Zp-内射模 Zp-平坦模 Zp-内射盖 Zp-平坦预包
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P-平坦模的特征
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作者 赵玉娥 陈正新 《河南科技大学学报(自然科学版)》 CAS 北大核心 2009年第2期88-90,共3页
给出了P-平坦模的定义,然后给出了P-平坦模的一些特征,而后定义了维数lTPD(R),并且研究了这个整体维数。得到了一些重要的结果:(1)每一个P-平坦模的商模是P-平坦的,等价于内射模的商模是P-平坦的;(2)R是左完全环等价于每一个左R-模是P-... 给出了P-平坦模的定义,然后给出了P-平坦模的一些特征,而后定义了维数lTPD(R),并且研究了这个整体维数。得到了一些重要的结果:(1)每一个P-平坦模的商模是P-平坦的,等价于内射模的商模是P-平坦的;(2)R是左完全环等价于每一个左R-模是P-平坦的。 展开更多
关键词 p-平坦模 平坦模 整体维数
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广义P-平坦性和广义P-内射性的一些刻画
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作者 王修建 杜先能 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2013年第4期608-612,共5页
利用同调代数方法分别给出了环R为左GP-内射环、左GPP-环和左GPF-环的一些等价刻画,通过引入GP-内射维数和GP-平坦维数的概念,证明了在左P-凝聚环条件下,环的左GP-内射整体维数等于环的右GP-弱维数,并给出了GP-内射维数和GP-平坦维数的... 利用同调代数方法分别给出了环R为左GP-内射环、左GPP-环和左GPF-环的一些等价刻画,通过引入GP-内射维数和GP-平坦维数的概念,证明了在左P-凝聚环条件下,环的左GP-内射整体维数等于环的右GP-弱维数,并给出了GP-内射维数和GP-平坦维数的若干新刻画. 展开更多
关键词 Gp-平坦模 Gp-内射模 Gp-平坦维数 Gp-内射维数
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P-平坦模和P-平坦维数的若干性质
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作者 王修建 祝家贵 赵建中 《皖西学院学报》 2008年第5期9-11,共3页
根据P-平坦模和P-平坦维数的定义给出了它们的一些性质。用P-平坦模刻画了正则环,同时对P-平坦维数也进行了探讨,得出了对于任意环R,rpfD(R)=sup{rpfd(R/I)|I是R的左主理想}等性质。
关键词 p-平坦模 p-内射模 p-平坦维数 正则环
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Gorenstein fp-平坦和强Gorenstein fp-平坦模
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作者 陈文静 《纯粹数学与应用数学》 CSCD 2014年第3期323-330,共8页
引入了Gorenstein fp-平坦模和强Gorenstein fp-平坦模的概念,讨论了这两类模的一些性质、联系以及稳定性.
关键词 GORENSTEIN fp-平坦模 强Gorenstein fp-平坦模 投射可解类
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n-P-凝聚环
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作者 乔虎生 郑奇莲 《西北师范大学学报(自然科学版)》 CAS 北大核心 2014年第1期20-23,共4页
设R是环,n是一个固定的正整数.本文引入了n-P-凝聚环及n-P-平坦模,并且用n-P-平坦模和n-P-内射模刻画了n-P-凝聚环.
关键词 n-p-凝聚环 n-p-平坦模 n-p-内射模
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Amplitude modulation and extreme events in turbulent channel flow 被引量:5
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作者 Y.C.Yao W.X.Huang C.X.Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第1期1-9,共9页
Amplitude modulation of near-wall turbulence by large-scale structures in the outer layer is investigated by direct numerical simulation of turbulent channel flows at Reynolds number Re= 540, 1000, 2000. The effect of... Amplitude modulation of near-wall turbulence by large-scale structures in the outer layer is investigated by direct numerical simulation of turbulent channel flows at Reynolds number Re= 540, 1000, 2000. The effect of modulation is obvious in the two-point cross-section correlation map, and the correlation coefficients increase significantly with the Reynolds number. The influence of modulation is reflected in the tail of the probability density function of the near-wall flow signals, which expands as the Reynolds number increases. The flatness factor provides a quantitative description of the high fluctuation events due to modulation. Vortical structures associated with modulation are revealed by conditionally averaging the flow field of the near-wall extreme events, providing a depiction of how the influence of the large-scale structures penetrate towards the near-wall region. 展开更多
关键词 Wall turbulence Amplitude modulation flatNESS Extreme events
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