3D printing techniques offer an effective method in fabricating complex radially multi-material structures.However,it is challenging for complex and delicate radially multi-material model geometries without supporting...3D printing techniques offer an effective method in fabricating complex radially multi-material structures.However,it is challenging for complex and delicate radially multi-material model geometries without supporting structures,such as tissue vessels and tubular graft,among others.In this work,we tackle these challenges by developing a polar digital light processing technique which uses a rod as the printing platform.The 3D model fabrication is accomplished through line projection.The rotation and translation of the rod are synchronized to project and illuminate the photosensitive material volume.By controlling the distance between the rod and the printing window,we achieved the printing of tubular structures with a minimum wall thickness as thin as 50 micrometers.By controlling the width of fine slits at the printing window,we achieved the printing of structures with a minimum feature size of 10 micrometers.Our process accomplished the fabrication of thin-walled tubular graft structure with a thickness of only 100 micrometers and lengths of several centimeters within a timeframe of just 100 s.Additionally,it enables the printing of axial multi-material structures,thereby achieving adjustable mechanical strength.This method is conducive to rapid customization of tubular grafts and the manufacturing of tubular components in fields such as dentistry,aerospace,and more.展开更多
On December 26, 2009, in the main control room of Shanghai Fengxian Converter Station, the voltage value on the screen rose from zero to 800 kV. This represented the demonstrative ±800-kV
The UHVAC 1 000-kV transmission system is so far the one with the most advanced transmission technique applied and highest operation voltage.There are no guidelines or standards available for the design of 1 000-kV ov...The UHVAC 1 000-kV transmission system is so far the one with the most advanced transmission technique applied and highest operation voltage.There are no guidelines or standards available for the design of 1 000-kV overhead transmission line in China.Study on key technologies and design schemes shall be carried out to ascertain the technical principles and construction standards for project construction,which are presented in this paper based on the Southeast Shanxi-Nanyang-Jingmen test and demonstration transmission line.A comparison and analysis of technical data and economic indices between UHV line and other lines are also described.展开更多
Using the cluster tilting theory,we investigate the tilting objects in the stable category of vector bundles on a weighted projective line of weight type(2,2,2,2).More precisely,a tilting object consisting of rank-two...Using the cluster tilting theory,we investigate the tilting objects in the stable category of vector bundles on a weighted projective line of weight type(2,2,2,2).More precisely,a tilting object consisting of rank-two bundles is constructed via the cluster tilting mutation.Moreover,the cluster tilting approach also provides a new method to classify the endomorphism algebras of the tilting objects in the category of coherent sheaves and the associated bounded derived category.展开更多
In the present paper, we introduce the concepts of Prüfer sheaves and adic sheaves over a weighted projective line of genus one or an elliptic curve, show that Prüfer sheaves and adic sheaves can characteriz...In the present paper, we introduce the concepts of Prüfer sheaves and adic sheaves over a weighted projective line of genus one or an elliptic curve, show that Prüfer sheaves and adic sheaves can characterize the category of coherent sheaves. Moreover, we describe the relationship between Prüfer sheaves and generic sheaves, and provide two methods to construct generic sheaves by using coherent sheaves and Prüfer sheaves.展开更多
We give a complete classification of tilting bundles over a weighted projective line of type （2, 3, 3）. This yields another realization of the tame concealed algebras of type E6.
We investigate the incidence algebras arising from one-branch extensions of“rectangles”.There are four different ways to form such extensions,and all four kinds of incidence algebras turn out to be derived equivalen...We investigate the incidence algebras arising from one-branch extensions of“rectangles”.There are four different ways to form such extensions,and all four kinds of incidence algebras turn out to be derived equivalent.We provide realizations for all of them as endomorphism algebra of tilting modules or tilting complexes over a Nakayama algebra.Meanwhile,an unexpected derived equivalence between Nakayama algebras N(2r-1,r)and N(2r-1,r+1)has been found.As an application,we obtain the explicit formulas of the Coxeter polynomials for a large family of Nakayama algebras,i.e.,the Nakayama algebras N(n,r)with n/2<r<n.展开更多
We determine the sizes of orbits from the action of subgroups of PSL(2,q) on projective line X = GF(q) ∪ {∞} with q a prime power and congruent to 1 modulo 4.As an example of its application,we construct some new fa...We determine the sizes of orbits from the action of subgroups of PSL(2,q) on projective line X = GF(q) ∪ {∞} with q a prime power and congruent to 1 modulo 4.As an example of its application,we construct some new families of simple 3-designs admitting PSL(2,q) as automorphism group.展开更多
This paper investigates the structure of the"missing part"from the category of coherent sheaves over a weighted projective line of weight type(2,2,n)to the category of finitely generated right modules on the...This paper investigates the structure of the"missing part"from the category of coherent sheaves over a weighted projective line of weight type(2,2,n)to the category of finitely generated right modules on the associated canonical algebra.By constructing a t-structure in the stable category of the vector bundle category,we show that the"missing part"is equivalent to the heart of the t-structure,hence it is abelian.Moreover,it is equivalent to the category of finitely generated modules on the path algebra of type An-1.展开更多
We study the dynamics of commuting rational maps with coefficients in Cp. By lifting the dynamics from P1（Cp） to Berkovich projective space P1 Berk, we prove that two nonlinear commuting maps have the same Berkovich...We study the dynamics of commuting rational maps with coefficients in Cp. By lifting the dynamics from P1（Cp） to Berkovich projective space P1 Berk, we prove that two nonlinear commuting maps have the same Berkovich Julia set and the same canonical measure. As a consequence, two nonlinear commuting maps with coefficient in Cp have the same classical Julia set. We also prove that they have the same pre-periodic Berkovich Fatou components.展开更多
基金supported financially by the Fundamental Research Funds for the Central Universities (YWF-22-K-101,YWF-23-L-805 and YWF-23-YG-QB-006)the support from the National Natural Science Foundation of China (12372106)Fundamental Research Funds for the Central Universities
文摘3D printing techniques offer an effective method in fabricating complex radially multi-material structures.However,it is challenging for complex and delicate radially multi-material model geometries without supporting structures,such as tissue vessels and tubular graft,among others.In this work,we tackle these challenges by developing a polar digital light processing technique which uses a rod as the printing platform.The 3D model fabrication is accomplished through line projection.The rotation and translation of the rod are synchronized to project and illuminate the photosensitive material volume.By controlling the distance between the rod and the printing window,we achieved the printing of tubular structures with a minimum wall thickness as thin as 50 micrometers.By controlling the width of fine slits at the printing window,we achieved the printing of structures with a minimum feature size of 10 micrometers.Our process accomplished the fabrication of thin-walled tubular graft structure with a thickness of only 100 micrometers and lengths of several centimeters within a timeframe of just 100 s.Additionally,it enables the printing of axial multi-material structures,thereby achieving adjustable mechanical strength.This method is conducive to rapid customization of tubular grafts and the manufacturing of tubular components in fields such as dentistry,aerospace,and more.
文摘On December 26, 2009, in the main control room of Shanghai Fengxian Converter Station, the voltage value on the screen rose from zero to 800 kV. This represented the demonstrative ±800-kV
文摘The UHVAC 1 000-kV transmission system is so far the one with the most advanced transmission technique applied and highest operation voltage.There are no guidelines or standards available for the design of 1 000-kV overhead transmission line in China.Study on key technologies and design schemes shall be carried out to ascertain the technical principles and construction standards for project construction,which are presented in this paper based on the Southeast Shanxi-Nanyang-Jingmen test and demonstration transmission line.A comparison and analysis of technical data and economic indices between UHV line and other lines are also described.
基金supported by National Natural Science Foundation of China(Grant Nos.11571286,11871404 and 11801473)the Fundamental Research Funds for the Central Universities of China(Grant Nos.20720180002 and 20720180006)。
文摘Using the cluster tilting theory,we investigate the tilting objects in the stable category of vector bundles on a weighted projective line of weight type(2,2,2,2).More precisely,a tilting object consisting of rank-two bundles is constructed via the cluster tilting mutation.Moreover,the cluster tilting approach also provides a new method to classify the endomorphism algebras of the tilting objects in the category of coherent sheaves and the associated bounded derived category.
基金Supported by National Nature Science Foundation of China(Grant Nos.11571286,11471269)the Natural Science Foundation of Fujian Province of China(Grant No.2016J01031)the Fundamental Research Funds for the Central Universities of China(Grant No.20720150006)
文摘In the present paper, we introduce the concepts of Prüfer sheaves and adic sheaves over a weighted projective line of genus one or an elliptic curve, show that Prüfer sheaves and adic sheaves can characterize the category of coherent sheaves. Moreover, we describe the relationship between Prüfer sheaves and generic sheaves, and provide two methods to construct generic sheaves by using coherent sheaves and Prüfer sheaves.
文摘We give a complete classification of tilting bundles over a weighted projective line of type （2, 3, 3）. This yields another realization of the tame concealed algebras of type E6.
基金Supported by the Natural Science Foundation of Xiamen(Grant No.3502Z20227184)the Natural Science Foundation of Fujian Province(Grant No.2022J01034)+2 种基金the Natural Science Foundation of Shanghai(Grant No.23ZR1435100)the National Natural Science Foundation of China(Grant Nos.12271448 and 12301054)the Fundamental Research Funds for Central Universities of China(Grant No.20720220043)。
文摘We investigate the incidence algebras arising from one-branch extensions of“rectangles”.There are four different ways to form such extensions,and all four kinds of incidence algebras turn out to be derived equivalent.We provide realizations for all of them as endomorphism algebra of tilting modules or tilting complexes over a Nakayama algebra.Meanwhile,an unexpected derived equivalence between Nakayama algebras N(2r-1,r)and N(2r-1,r+1)has been found.As an application,we obtain the explicit formulas of the Coxeter polynomials for a large family of Nakayama algebras,i.e.,the Nakayama algebras N(n,r)with n/2<r<n.
基金supported by National Natural Science Foundation of China (Grant Nos.10871205 and 10971252)the Research Foundation of Education Bureau of Hunan Province of China (Grant No. 08c021)
文摘We determine the sizes of orbits from the action of subgroups of PSL(2,q) on projective line X = GF(q) ∪ {∞} with q a prime power and congruent to 1 modulo 4.As an example of its application,we construct some new families of simple 3-designs admitting PSL(2,q) as automorphism group.
基金supported by National Natural Science Foundation of China(Grant Nos.11201386,10931006,11071040 and 11201388)the Natural Science Foundation of Fujian Province of China(Grant No.2012J05009)
文摘This paper investigates the structure of the"missing part"from the category of coherent sheaves over a weighted projective line of weight type(2,2,n)to the category of finitely generated right modules on the associated canonical algebra.By constructing a t-structure in the stable category of the vector bundle category,we show that the"missing part"is equivalent to the heart of the t-structure,hence it is abelian.Moreover,it is equivalent to the category of finitely generated modules on the path algebra of type An-1.
基金Supported by National Natural Science Foundation of China (Grant Nos.10831008 and 11231009)
文摘We study the dynamics of commuting rational maps with coefficients in Cp. By lifting the dynamics from P1（Cp） to Berkovich projective space P1 Berk, we prove that two nonlinear commuting maps have the same Berkovich Julia set and the same canonical measure. As a consequence, two nonlinear commuting maps with coefficient in Cp have the same classical Julia set. We also prove that they have the same pre-periodic Berkovich Fatou components.
