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排序方式: 共有2177条查询结果,搜索用时 15 毫秒
31.
Rasoul Ahangari Maleki 《代数通讯》2017,45(2):514-520
32.
Zhi CHENG Yu YE 《数学学报(英文版)》2007,23(6):965-972
We introduce the category of t-fold modules which is a full subcategory of graded modules over a graded algebra. We show that this subcategory and hence the subcategory of t-Koszul modules are both closed under extensions and cokernels of monomorphisms. We study the one-point extension algebras, and a necessary and sufficient condition for such an algebra to be t-Koszul is given. We also consider the conditions such that the category of t-Koszul modules and the category of quadratic modules coincide. 相似文献
33.
讨论了Gpp环和Gp-内射模的一些性质;讨论了Gp-内射模和R-内射模的关系及Gp-内射模和Gpp环的若干联系.最后讨论了和Gpp环有关的有限生成模的投射盖问题. 相似文献
34.
The computational problems of two special determinants are investigated. Those tion for computing Fredholm integral equation of the second kind. The main tool to be used in this paper is the well-known Schur complement theorem. 相似文献
35.
We prove the existence of solutions for some semilinear elliptic equations in the appropriate H4 spaces using the fixed‐point technique where the elliptic equation contains fourth‐order differential operators with and without Fredholm property, generalizing the previous results. 相似文献
36.
利用自行研制的空心微球耐外压装置和充气装置,测试了目前激光惯性约束聚变实验打靶使用的空心玻璃微球耐内压能力和耐外压能力。空心玻璃微球采用液滴法制备,直径为180~250 mm、壁厚为0.8~4.0 mm。理论计算表明,当微球纵横比超过90时,耐外压能力与球壳材料的杨氏模量有关,由此测量得到的空心玻璃微球杨氏模量为55~75 GPa。玻璃微球的耐内压能力主要与球壳材料的抗拉强度有关,实验测量得到的玻璃微球抗拉强度为90~140 MPa。 相似文献
37.
运用Mawhin重合度理论建立了二阶Stieltjes积分边值问题解的存在性定理,其所得结果推广了多点边值问题已有的一些结论。 相似文献
38.
In this paper, we propose an original approach to the solution of Fredholm equations of the second kind. We interpret the standard Von Neumann expansion of the solution as an expectation with respect to a probability distribution defined on a union of subspaces of variable dimension. Based on this representation, it is possible to use trans-dimensional Markov chain Monte Carlo (MCMC) methods such as Reversible Jump MCMC to approximate the solution numerically. This can be an attractive alternative to standard Sequential Importance Sampling (SIS) methods routinely used in this context. To motivate our approach, we sketch an application to value function estimation for a Markov decision process. Two computational examples are also provided. 相似文献
39.
Rod Gow 《Geometriae Dedicata》1997,64(3):283-295
Let K be a field of characteristic 2 and letV be a vector space of dimension 2m over K. Let f be a non-degenerate alternating bilinear form defined on V × V. The symplectic group Sp(2m, K) acts on the exterior powers
k
V for 0 k. 2m There is a contraction map defined on the exterior algebra , which commutes with the Sp(2m, K) action and satisfies 2 = 0 and (
k
V)
k–1
V We prove that (
k
V)= ker
k–1
V except when k=m+2. In the exceptional case, (
m+2
V) has codimension 2m in ker
m
V and we show that the quotient module ker
m
V/
m+2
V is a spin module for Sp(2m,K). When K is algebraically closed, we show that this spin module occurs with multiplicity 1 in
m
V and multiplicity 0 in all other components of V. 相似文献
40.
Crossed Modules and Quantum Groups in Braided Categories 总被引:2,自引:0,他引:2
Yu. N. Bespalov 《Applied Categorical Structures》1997,5(2):155-204
Let A be a Hopf algebra in a braided category
. Crossed modules over A are introduced and studied as objects with both module and comodule structures satisfying a compatibility condition. The category
of crossed modules is braided and is a concrete realization of a known general construction of a double or center of a monoidal category. For a quantum braided group
the corresponding braided category of modules
is identified with a full subcategory in
. The connection with cross products is discussed and a suitable cross product in the class of quantum braided groups is built. Majid–Radford theorem, which gives equivalent conditions for an ordinary Hopf algebra to be such a cross product, is generalized to the braided category. Majid's bosonization theorem is also generalized. 相似文献