In this paper, we study the extension of isometries between the unit spheresof some Banach spaces E and the spaces C(Ω). We obtain that if the set sm.S_1(E) of all smoothpoints of the unit sphere S_1(E) is dense in S...In this paper, we study the extension of isometries between the unit spheresof some Banach spaces E and the spaces C(Ω). We obtain that if the set sm.S_1(E) of all smoothpoints of the unit sphere S_1(E) is dense in S_1(E), then under some condition, every surjectiveisometry V_0 from S_1(E) onto S_1(C(Ω)) can be extended to be a real linearly isometric map V of Eonto C(Ω). From this result we also obtain some corollaries. This is the first time we study thisproblem on different typical spaces, and the method of proof is also very different too.展开更多
This paper is devoted to studying the recollement of the categories of finitely generated modules over finite dimensional algebras. We prove that for algebras A, B and C, if A-mod admits a recollement relative to B-mo...This paper is devoted to studying the recollement of the categories of finitely generated modules over finite dimensional algebras. We prove that for algebras A, B and C, if A-mod admits a recollement relative to B-mod and C-mod, then A[R]-mod admits a recollement relative to B[S]-mod and C-mod, where A[R]and B[S]are the one-point extensions of A by R and of B by S.展开更多
In this article,we use some analytic and geometric characters of the smooth points in a sphere to study the isometric extension problem in the separable or reflexive real Banach spaces.We obtain that under some condit...In this article,we use some analytic and geometric characters of the smooth points in a sphere to study the isometric extension problem in the separable or reflexive real Banach spaces.We obtain that under some condition the answer to this problem is affirmative.展开更多
In this paper, based on the smooth point of the unit ball and its support linear functional,we show two equivalent formulations of the isometric extension problem between the unit spheres of strictly convex two-dimens...In this paper, based on the smooth point of the unit ball and its support linear functional,we show two equivalent formulations of the isometric extension problem between the unit spheres of strictly convex two-dimensional normed spaces. We prove that these equivalent formulations have a positive answer in a special case.展开更多
Let R[P] be the one point extension of a k-algebra R by a projective R-module P.We prove that the extension of a complete ideal cotorsion pair in R-Mod is still a complete ideal cotorsion pair in R[P]-Mod.As an applic...Let R[P] be the one point extension of a k-algebra R by a projective R-module P.We prove that the extension of a complete ideal cotorsion pair in R-Mod is still a complete ideal cotorsion pair in R[P]-Mod.As an application,it is obtainable that the operation(-)_(m)[P]satisfies the so-called distributive law relating the operations of products and extensions of ideals under appropriate conditions.展开更多
我们讨论了一类具有抛物不动点的二维保面积映射的一种受摄扩张:T_3:()? X_(n+1)=X_n-Ay_2~3+B sin z_n,y_(n+1)=x_n+y_n-Ay_n^3+C sin x_n+1,z_n+1=z_n+D sin y_(n+1)+E(mod 2π),其中A、B、C、D、E 为参数。我们发现了一些有趣的性态...我们讨论了一类具有抛物不动点的二维保面积映射的一种受摄扩张:T_3:()? X_(n+1)=X_n-Ay_2~3+B sin z_n,y_(n+1)=x_n+y_n-Ay_n^3+C sin x_n+1,z_n+1=z_n+D sin y_(n+1)+E(mod 2π),其中A、B、C、D、E 为参数。我们发现了一些有趣的性态,有的与文[3],[5]中的结果相似。我们还发现了一些特殊的性态:当 B=C=D=0.03,E=0.009时,仅在围绕原点的环域中产生二维不变流形(不变管子)。当摄动参数 B、C、D、E 减小时,相应的环域扩大了,即在受摄扩张下接近抛物不动点的有序区要比离不动点运的环域内的有序区更容易受到破坏。展开更多
文摘In this paper, we study the extension of isometries between the unit spheresof some Banach spaces E and the spaces C(Ω). We obtain that if the set sm.S_1(E) of all smoothpoints of the unit sphere S_1(E) is dense in S_1(E), then under some condition, every surjectiveisometry V_0 from S_1(E) onto S_1(C(Ω)) can be extended to be a real linearly isometric map V of Eonto C(Ω). From this result we also obtain some corollaries. This is the first time we study thisproblem on different typical spaces, and the method of proof is also very different too.
基金the National Natural Science Foundation of China (Grant No. 10671161)
文摘This paper is devoted to studying the recollement of the categories of finitely generated modules over finite dimensional algebras. We prove that for algebras A, B and C, if A-mod admits a recollement relative to B-mod and C-mod, then A[R]-mod admits a recollement relative to B[S]-mod and C-mod, where A[R]and B[S]are the one-point extensions of A by R and of B by S.
基金Supported by National Natural Science Foundation of China(Grant No.11371201)
文摘In this article,we use some analytic and geometric characters of the smooth points in a sphere to study the isometric extension problem in the separable or reflexive real Banach spaces.We obtain that under some condition the answer to this problem is affirmative.
基金supported by the National Natural Science Foundation of China(Grant No.11371201)supported by the National Natural Science Foundation of China(Grant No.11601371)
文摘In this paper, based on the smooth point of the unit ball and its support linear functional,we show two equivalent formulations of the isometric extension problem between the unit spheres of strictly convex two-dimensional normed spaces. We prove that these equivalent formulations have a positive answer in a special case.
基金Supported by Zhejiang Provincial Natural Science Foundation of China(LY18A010032)
文摘Let R[P] be the one point extension of a k-algebra R by a projective R-module P.We prove that the extension of a complete ideal cotorsion pair in R-Mod is still a complete ideal cotorsion pair in R[P]-Mod.As an application,it is obtainable that the operation(-)_(m)[P]satisfies the so-called distributive law relating the operations of products and extensions of ideals under appropriate conditions.
文摘我们讨论了一类具有抛物不动点的二维保面积映射的一种受摄扩张:T_3:()? X_(n+1)=X_n-Ay_2~3+B sin z_n,y_(n+1)=x_n+y_n-Ay_n^3+C sin x_n+1,z_n+1=z_n+D sin y_(n+1)+E(mod 2π),其中A、B、C、D、E 为参数。我们发现了一些有趣的性态,有的与文[3],[5]中的结果相似。我们还发现了一些特殊的性态:当 B=C=D=0.03,E=0.009时,仅在围绕原点的环域中产生二维不变流形(不变管子)。当摄动参数 B、C、D、E 减小时,相应的环域扩大了,即在受摄扩张下接近抛物不动点的有序区要比离不动点运的环域内的有序区更容易受到破坏。