Let A be a finite dimensional k-algebra and T be a supportτ-tilting right A-module.In this note,we give lower and upper bounds for the global dimension of the endomorphism algebra End_(A)(T)under some mild conditions...Let A be a finite dimensional k-algebra and T be a supportτ-tilting right A-module.In this note,we give lower and upper bounds for the global dimension of the endomorphism algebra End_(A)(T)under some mild conditions.Finally,we give some examples to illustrate that both the upper and lower bounds can be reached.展开更多
Associated with each finite directed quiver Q is a quasi-hereditary algebra. the so-called twisted double of the path algebra kQ. Characteristic tilting modules over this class of quasi-hereditary algebras are constru...Associated with each finite directed quiver Q is a quasi-hereditary algebra. the so-called twisted double of the path algebra kQ. Characteristic tilting modules over this class of quasi-hereditary algebras are constructed. Their endonorphism algebras are explicitly described. It turns out that this class of quasi-hereditary algebras is closed under taking the Ringel dual.展开更多
The purpose of this paper is to provide the TTF-theories and investigate the comparisons of recollements(one-sided recollements) both induced by the BB-tilting modules.
Let G be a semisimple group over an algebraically closed field of characteristic p > 0. We give a(partly conjectural) closed formula for the character of many indecomposable tilting rational G-modules assuming that...Let G be a semisimple group over an algebraically closed field of characteristic p > 0. We give a(partly conjectural) closed formula for the character of many indecomposable tilting rational G-modules assuming that p is large.展开更多
Throughout this note, we assume that k is an algebraically closed field and A is a basic connected finite-dimensional algebra over k (associative, with identity). All modules over an algebra A are finitely generated l...Throughout this note, we assume that k is an algebraically closed field and A is a basic connected finite-dimensional algebra over k (associative, with identity). All modules over an algebra A are finitely generated left A-modules. We usually denote, up to isomorphism, by {P_A(a)|a∈I} the set of all indecomposable projective modules, by {E_A(a)|a∈I} the set of all indecomposable injective modules, and by {S_A(a)|a∈I} the set of all simple modules,展开更多
Let A be a basic, connected and finite-dimensional algebra over an algebraically closed field k. A tilting module A^T is called separating if the torsion theory (F(A^T), G(A^T)) induced by A^T is splitting in A-mod, i...Let A be a basic, connected and finite-dimensional algebra over an algebraically closed field k. A tilting module A^T is called separating if the torsion theory (F(A^T), G(A^T)) induced by A^T is splitting in A-mod, i. e. any indecomposable module A^M belongs either to F(A^T) or to G(A^T). In this note we prove the following main result by using the representation theory of representation-infinite hereditary algebra.展开更多
Let be a connected finite quiver without oriented cycle, A=k(?) the corresponding path algebra with k being an algebraically closed field, A<sup>T</sup> a preprojective tilting module. B=End<sub>A&...Let be a connected finite quiver without oriented cycle, A=k(?) the corresponding path algebra with k being an algebraically closed field, A<sup>T</sup> a preprojective tilting module. B=End<sub>A</sub>T. Then B is called a tame (resp. wild)concealed algebra provided is an Euclidean (resp. wild ) graph. The following result is important in the representation theory of tame concealed algebras (see [1,4.9]): if A is tame concealed, T= T<sub>0</sub>⊕ T<sub>1</sub> a tilting module with T<sub>0</sub> nonzero preprojective and T<sub>1</sub> regular, then End<sub>A</sub>T<sub>0</sub> is tame concealed. The main purpose of this note is to generalize it to the 'wild' case. For this we generally consider the endomorphism algebra of preprojective partial tilting modules over a concealed algebra. For the notations the readers can refer to Ref.[1].展开更多
Motivated by T-tilting theory developed by T. Adachi, O. Iyama, I. Reiten, for a finite-dimensional algebra A with action by a finite group G, we introduce the notion of G-stable support τ-tilting modules. Then we es...Motivated by T-tilting theory developed by T. Adachi, O. Iyama, I. Reiten, for a finite-dimensional algebra A with action by a finite group G, we introduce the notion of G-stable support τ-tilting modules. Then we establish bijections among G-stable support τ-tilting modules over ∧, G-stable two-term silting complexes in the homotopy category of bounded complexes of finitely generated projective ∧-modules, and G-stable functorially finite torsion classes in the category of finitely generated left ∧-modules. In the case when ∧ is the endomorphism of a G-stable cluster-tilting object T over a Horn-finite 2-Calabi- Yau triangulated category L with a G-action, these are also in bijection with G-stable cluster-tilting objects in L. Moreover, we investigate the relationship between stable support τ-tilitng modules over ∧ and the skew group algebra ∧G.展开更多
We consider whether the tilting properties of a tilting A-module T and a tilting B-module T′ can convey to their tensor product T T′. The main result is that T T′ turns out to be an (n + m)-tilting A B-modu...We consider whether the tilting properties of a tilting A-module T and a tilting B-module T′ can convey to their tensor product T T′. The main result is that T T′ turns out to be an (n + m)-tilting A B-module, where T is an m-tilting A-module and T′ is an n-tilting B-module.展开更多
Let T be a tilting A-module over a path algebra of Dynkin type.We prove that if the indecomposable direct summands of T are in the differentτ-orbits of the AR-quiver of A,then T is a complete slice module.
This paper gives the relationships among partial tilting objects (tilting objects) of categories of graded left A-modules of type G, left A-modules, left Ae-modules and A#-modules, and then proves that for graded pa...This paper gives the relationships among partial tilting objects (tilting objects) of categories of graded left A-modules of type G, left A-modules, left Ae-modules and A#-modules, and then proves that for graded partial tilting modules, there exist the Bongartz complements in the category of graded A-modules.展开更多
Tilting pair was introduced by Miyashita in 2001 as a generalization of tilting module. In this paper, we construct a tilting left Endh(C)-right Endh(T)-bimodule for a given tilting pairs (C,T) in modh, where A ...Tilting pair was introduced by Miyashita in 2001 as a generalization of tilting module. In this paper, we construct a tilting left Endh(C)-right Endh(T)-bimodule for a given tilting pairs (C,T) in modh, where A is an Artin algebra.展开更多
The tilt angle of the small scale existing solar power plants is 60 degree and it is 45 degree for the megawatts(MW)class solar power plant in Mongolia.However,the PV module which is installed with 45 degree accumulat...The tilt angle of the small scale existing solar power plants is 60 degree and it is 45 degree for the megawatts(MW)class solar power plant in Mongolia.However,the PV module which is installed with 45 degree accumulates lots of snow during the winter.Currently,all solar PV systems installed in Mongolia are fixed the direction and tilt angles.According to the previous research result,the tilt angle of those systems was not suitable for using especially in the winter.The PV module which is installed with 60 degree does not accumulates snow even during the autumn and spring.According to the National Aeronautics and Space Administration(NASA)solar radiation database,solar irradiance for equator facing is largest at 32-degree tilted angle during the summer,47-degree during the spring and autumn,at 62-degree during the winter.The results of this paper show,the tilt angle of the PV module should be adjusted at least twice a year.For instance,the tilt angle will be adjusted at the 32-degree from 15th March to 24th August,at the 62-degree from 25th August to 15th March.In this case,the annual total energy output will be increased up to 30%than present production.展开更多
设R为交换 Noether 环,给出关于半对偶R-模W的n-倾斜模的定义.利用同调代数的方法,讨论n-倾斜模(未必有限生成)与n-W-倾斜模之间的关系,研究n-W-倾斜模的若干性质和等价刻画.结果表明,T是n-W-倾斜模当且仅当 Hom R(W,T)是n-倾斜模;T是n...设R为交换 Noether 环,给出关于半对偶R-模W的n-倾斜模的定义.利用同调代数的方法,讨论n-倾斜模(未必有限生成)与n-W-倾斜模之间的关系,研究n-W-倾斜模的若干性质和等价刻画.结果表明,T是n-W-倾斜模当且仅当 Hom R(W,T)是n-倾斜模;T是n-倾斜模当且仅当W R T是n-W-倾斜模.展开更多
IN the theory of infinite abelian groups, the concepts of torsion-free groups and divisible groups are well known. We know that there exists, up to isomorphism, one and only one abelian group which is both torsion-fre...IN the theory of infinite abelian groups, the concepts of torsion-free groups and divisible groups are well known. We know that there exists, up to isomorphism, one and only one abelian group which is both torsion-free and divisible at the same time. This is the additive group Q of the rational numbers. Q plays an important role in the study of infinite-abelian groups. The theory of infinite-dirnensional modules over a finite-dimensional algebra runs similarly to the theory of infinite abelian groups but there are also some substantial differences.展开更多
目的:评价前囊抛光对白内障超声乳化术后视觉质量的影响。方法:前瞻性随机对照研究。纳入2021-11/2022-06于应急总医院眼科行白内障超声乳化联合人工晶状体(IOL)植入术的年龄相关性白内障患者65例73眼,随机分为抛光组(30例35眼,术中行...目的:评价前囊抛光对白内障超声乳化术后视觉质量的影响。方法:前瞻性随机对照研究。纳入2021-11/2022-06于应急总医院眼科行白内障超声乳化联合人工晶状体(IOL)植入术的年龄相关性白内障患者65例73眼,随机分为抛光组(30例35眼,术中行前后囊联合抛光)和对照组(35例38眼,术中仅行后囊抛光)。观察术后1wk,1、3、6mo最佳矫正视力,术后3、6mo测量前囊口面积,并使用Pentacam三维眼前节系统评估后囊膜混浊程度(P评分)、IOL倾斜度和偏心量,使用OPD-ScanⅢ光程差分析系统评估波前像差、点扩散函数(PSF)的斯特列尔比(SR)和调制传递函数(MTF)。结果:术后1wk,1、3、6mo,抛光组患者最佳矫正视力均优于对照组(P<0.05)。术后3、6mo,两组患者前囊口面积、后囊膜混浊程度(P评分)、IOL偏心量、PSF的SR值和MTF均无差异(P>0.05)。术后3mo,两组患者IOL倾斜度、波前像差均无差异(P>0.05),但术后6mo,抛光组IOL倾斜度小于对照组[(1.65±0.60)°vs(2.34±0.43)°,P<0.001)],波前像差也小于对照组(0.03±0.01μm vs 0.06±0.03μm,P<0.001)。结论:白内障超声乳化吸除术中行360°抛光前后囊膜能提高术后最佳矫正视力,且术后IOL倾斜度更低、波前像差更小,视觉质量更好。展开更多
基金supported by the National Natural Science Foundation of China(11971255,11901567,12071120)supported by the Hunan Provincial Natural Science Foundation of China(2023JJ30008)the National Natural Science Foundation of China(12371034).
文摘Let A be a finite dimensional k-algebra and T be a supportτ-tilting right A-module.In this note,we give lower and upper bounds for the global dimension of the endomorphism algebra End_(A)(T)under some mild conditions.Finally,we give some examples to illustrate that both the upper and lower bounds can be reached.
基金Supported partially by Alexander von Humboldt FoundationNational Natural Science Foundation of China (Grant No. 19971009).
文摘Associated with each finite directed quiver Q is a quasi-hereditary algebra. the so-called twisted double of the path algebra kQ. Characteristic tilting modules over this class of quasi-hereditary algebras are constructed. Their endonorphism algebras are explicitly described. It turns out that this class of quasi-hereditary algebras is closed under taking the Ringel dual.
基金supported by National Natural Science Foundation of China(Grant No.10931006)
文摘The purpose of this paper is to provide the TTF-theories and investigate the comparisons of recollements(one-sided recollements) both induced by the BB-tilting modules.
基金G.Lusztig was supported by National Science Foundation of USA(GrantNo.DMS-1303060)by a Simons Fellowship
文摘Let G be a semisimple group over an algebraically closed field of characteristic p > 0. We give a(partly conjectural) closed formula for the character of many indecomposable tilting rational G-modules assuming that p is large.
基金Project supported by the National Natural Science Foundation of China.
文摘Throughout this note, we assume that k is an algebraically closed field and A is a basic connected finite-dimensional algebra over k (associative, with identity). All modules over an algebra A are finitely generated left A-modules. We usually denote, up to isomorphism, by {P_A(a)|a∈I} the set of all indecomposable projective modules, by {E_A(a)|a∈I} the set of all indecomposable injective modules, and by {S_A(a)|a∈I} the set of all simple modules,
基金Proiect supported by the National Natural Science Foundation of China
文摘Let A be a basic, connected and finite-dimensional algebra over an algebraically closed field k. A tilting module A^T is called separating if the torsion theory (F(A^T), G(A^T)) induced by A^T is splitting in A-mod, i. e. any indecomposable module A^M belongs either to F(A^T) or to G(A^T). In this note we prove the following main result by using the representation theory of representation-infinite hereditary algebra.
基金Project supported by the National Natural Science Foundation of China
文摘Let be a connected finite quiver without oriented cycle, A=k(?) the corresponding path algebra with k being an algebraically closed field, A<sup>T</sup> a preprojective tilting module. B=End<sub>A</sub>T. Then B is called a tame (resp. wild)concealed algebra provided is an Euclidean (resp. wild ) graph. The following result is important in the representation theory of tame concealed algebras (see [1,4.9]): if A is tame concealed, T= T<sub>0</sub>⊕ T<sub>1</sub> a tilting module with T<sub>0</sub> nonzero preprojective and T<sub>1</sub> regular, then End<sub>A</sub>T<sub>0</sub> is tame concealed. The main purpose of this note is to generalize it to the 'wild' case. For this we generally consider the endomorphism algebra of preprojective partial tilting modules over a concealed algebra. For the notations the readers can refer to Ref.[1].
基金The authors would like to thank Dong Yang and Yuefei Zheng for their helpful discussion. This work was partially supported by the National Natural Science Foundation of China (Grant No. 11571164) and a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Motivated by T-tilting theory developed by T. Adachi, O. Iyama, I. Reiten, for a finite-dimensional algebra A with action by a finite group G, we introduce the notion of G-stable support τ-tilting modules. Then we establish bijections among G-stable support τ-tilting modules over ∧, G-stable two-term silting complexes in the homotopy category of bounded complexes of finitely generated projective ∧-modules, and G-stable functorially finite torsion classes in the category of finitely generated left ∧-modules. In the case when ∧ is the endomorphism of a G-stable cluster-tilting object T over a Horn-finite 2-Calabi- Yau triangulated category L with a G-action, these are also in bijection with G-stable cluster-tilting objects in L. Moreover, we investigate the relationship between stable support τ-tilitng modules over ∧ and the skew group algebra ∧G.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (Grant Nos. 11471269, 61373140), the Natural Science Foundation of Fujian Province (2016J01002), and 2016 Incubation Program for Scientific Research Talent of Distinguished Young of Colledges and Universities in Fujian Province.
文摘We consider whether the tilting properties of a tilting A-module T and a tilting B-module T′ can convey to their tensor product T T′. The main result is that T T′ turns out to be an (n + m)-tilting A B-module, where T is an m-tilting A-module and T′ is an n-tilting B-module.
基金supported by the National Natural Science Foundation of China(Grant No.10701062)the Huaqiao University Natural Science Foundation(Grant No.01HZR05).
文摘Let T be a tilting A-module over a path algebra of Dynkin type.We prove that if the indecomposable direct summands of T are in the differentτ-orbits of the AR-quiver of A,then T is a complete slice module.
基金the National Natural Science Foundation of China (Nos. 10371101 10671161)+2 种基金 the Natural Science Foundation of Fujian Province (Nos. Z0511022) and the Foundation of the Education Committee of Fujian Province (Nos. JA050206 JA06008 JB04215).
文摘This paper gives the relationships among partial tilting objects (tilting objects) of categories of graded left A-modules of type G, left A-modules, left Ae-modules and A#-modules, and then proves that for graded partial tilting modules, there exist the Bongartz complements in the category of graded A-modules.
基金Supported by the National Natural Science Foundation of China (Grant Nos.1097102410826036)+2 种基金the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No.200802860024)the Natural Science Foundation of Jiangsu Province (Grant No.BK2010393)the Scientific Research Foundation of Guangxi University (Grant No.XJZ100246)
文摘Tilting pair was introduced by Miyashita in 2001 as a generalization of tilting module. In this paper, we construct a tilting left Endh(C)-right Endh(T)-bimodule for a given tilting pairs (C,T) in modh, where A is an Artin algebra.
文摘The tilt angle of the small scale existing solar power plants is 60 degree and it is 45 degree for the megawatts(MW)class solar power plant in Mongolia.However,the PV module which is installed with 45 degree accumulates lots of snow during the winter.Currently,all solar PV systems installed in Mongolia are fixed the direction and tilt angles.According to the previous research result,the tilt angle of those systems was not suitable for using especially in the winter.The PV module which is installed with 60 degree does not accumulates snow even during the autumn and spring.According to the National Aeronautics and Space Administration(NASA)solar radiation database,solar irradiance for equator facing is largest at 32-degree tilted angle during the summer,47-degree during the spring and autumn,at 62-degree during the winter.The results of this paper show,the tilt angle of the PV module should be adjusted at least twice a year.For instance,the tilt angle will be adjusted at the 32-degree from 15th March to 24th August,at the 62-degree from 25th August to 15th March.In this case,the annual total energy output will be increased up to 30%than present production.
文摘设R为交换 Noether 环,给出关于半对偶R-模W的n-倾斜模的定义.利用同调代数的方法,讨论n-倾斜模(未必有限生成)与n-W-倾斜模之间的关系,研究n-W-倾斜模的若干性质和等价刻画.结果表明,T是n-W-倾斜模当且仅当 Hom R(W,T)是n-倾斜模;T是n-倾斜模当且仅当W R T是n-W-倾斜模.
文摘IN the theory of infinite abelian groups, the concepts of torsion-free groups and divisible groups are well known. We know that there exists, up to isomorphism, one and only one abelian group which is both torsion-free and divisible at the same time. This is the additive group Q of the rational numbers. Q plays an important role in the study of infinite-abelian groups. The theory of infinite-dirnensional modules over a finite-dimensional algebra runs similarly to the theory of infinite abelian groups but there are also some substantial differences.
文摘目的:评价前囊抛光对白内障超声乳化术后视觉质量的影响。方法:前瞻性随机对照研究。纳入2021-11/2022-06于应急总医院眼科行白内障超声乳化联合人工晶状体(IOL)植入术的年龄相关性白内障患者65例73眼,随机分为抛光组(30例35眼,术中行前后囊联合抛光)和对照组(35例38眼,术中仅行后囊抛光)。观察术后1wk,1、3、6mo最佳矫正视力,术后3、6mo测量前囊口面积,并使用Pentacam三维眼前节系统评估后囊膜混浊程度(P评分)、IOL倾斜度和偏心量,使用OPD-ScanⅢ光程差分析系统评估波前像差、点扩散函数(PSF)的斯特列尔比(SR)和调制传递函数(MTF)。结果:术后1wk,1、3、6mo,抛光组患者最佳矫正视力均优于对照组(P<0.05)。术后3、6mo,两组患者前囊口面积、后囊膜混浊程度(P评分)、IOL偏心量、PSF的SR值和MTF均无差异(P>0.05)。术后3mo,两组患者IOL倾斜度、波前像差均无差异(P>0.05),但术后6mo,抛光组IOL倾斜度小于对照组[(1.65±0.60)°vs(2.34±0.43)°,P<0.001)],波前像差也小于对照组(0.03±0.01μm vs 0.06±0.03μm,P<0.001)。结论:白内障超声乳化吸除术中行360°抛光前后囊膜能提高术后最佳矫正视力,且术后IOL倾斜度更低、波前像差更小,视觉质量更好。