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201.
202.
We investigate the Induced Subgraph Isomorphism problem with non-standard parameterization, where the parameter is the difference |V(G)|−|V(H)| with H and G being the smaller and the larger input graph, respectively. Intuitively, we can interpret this problem as “cleaning” the graph G, regarded as a pattern containing extra vertices indicating errors, in order to obtain the graph H representing the original pattern. We show fixed-parameter tractability of the cases where both H and G are planar and H is 3-connected, or H is a tree and G is arbitrary. We also prove that the problem when H and G are both 3-connected planar graphs is NP-complete without parameterization. 相似文献
203.
Choonkil Park Jung Rye Lee Dong Yun Shin 《Journal of Applied Analysis & Computation》2015,5(4):635-650
In this paper, we investigate homomorphisms in proper CQ-algebras, proper Lie CQ-algebras and proper Jordan CQ-algebras and deriva-tions on proper CQ-algebras, proper Lie CQ-algebras and proper JordanCQ-algebras associated with the Cauchy-Jensen functional equation2f(x + y2+ z)= f(x) + f(y) + 2f(z);which was introduced and investigated in [3, 28].Furthermore, Isometries and isometric isomorphisms in proper CQ-algebrasare studied. 相似文献
204.
利用金刚石压腔同步辐射X射线就位衍射技术,在室温、最高压力达13 GPa条件下,对采自云南个旧锡矿的天然锡石做了X衍射测量。结果表明,在实验压力范围内锡石未发生相变,其晶胞参数随压力增大而逐渐减小。与前人合成锡石实验结果相比,本次实验测定的晶胞参数偏大。由Birch状态方程对实验结果p-V进行最小二乘法拟合,得出锡石的KT(0)=228 GPa。分析认为,在天然矿物晶体中,Zr对Sn的类质同象置换是晶胞参数偏大的主要原因。 相似文献
205.
In this paper, we prove the Hyers-Ulam-Rassias stability of isometric homomorphisms in proper CQ*-algebras for the following Cauchy-Jensen additive mapping: 2f[(x1+x2)/2+y]=f(x1)+f(x2)+2f(y) The concept of Hyers-Ulam-Rassias stability originated from the Th.M. Rassias' stability theorem that appeared in the paper: On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc., 72 (1978), 297-300. This is applied to investigate isometric isomorphisms between proper CQ*-algebras. 相似文献
206.
Yong Ge TIAN 《数学学报(英文版)》2006,22(1):289-300
For any element a in a generalized 2^n-dimensional Clifford algebra Lln (F) over an arbitrary field F of characteristic not equal to two, it is shown that there exits a universal invertible matrix Pn over Lln(F) such that Pn^-1DnPn= φ(α)∈F^2n×2n, where φ(a) is a matrix representation of α over and Dα is a diagonal matrix consisting of a or its conjugate. 相似文献
207.
We prove that two dual operator spaces X and Y are stably isomorphic if and only if there exist completely isometric normal representations ? and ψ of X and Y, respectively, and ternary rings of operators M1, M2 such that and . We prove that this is equivalent to certain canonical dual operator algebras associated with the operator spaces being stably isomorphic. We apply these operator space results to prove that certain dual operator algebras are stably isomorphic if and only if they are isomorphic. Consequently, we obtain that certain complex domains are biholomorphically equivalent if and only if their algebras of bounded analytic functions are Morita equivalent in our sense. Finally, we provide examples motivated by the theory of CSL algebras. 相似文献
208.
Peter Danchev 《Southeast Asian Bulletin of Mathematics》2002,25(4):589-598
We let FG be the group algebra of an abelian group G over a field F with characteristic p. Also, we define Gp and S(FG) as the groups of all p-primary normed elements in G and FG, respectively. We prove that if Gp is Hausdorff and both F and G have cardinalities not exceeding
1, then S(FG)/Gp is a direct sum of cyclics. Thus Gp is a direct factor of S(FG), and in particular G is a direct factor of the group of all normalized units V(FG), provided that the torsion part of G is a p-group. This answers a question posed by us in Hokkaido Math. J. (2000). Moreover we establish that if G is p-splitting, then any F-isomorphism of the group algebras FG and FH implies that H is p-splitting. We also show that if G is of power
1 whose p-component Gp is a direct sum of torsion-complete groups and F has power p, then the F-isomorphism of FG and FH for any group H yields an isomorphism between Gp and Hp. In particular, when G is of power
1 and is p-mixed of torsion-free rank 1 whose Gp is torsion-complete, we have G H. If F is in power p and G, with cardinality
1, is a direct sum of p-local algebraically compact groups such that FG FH as F-algebras for some group H, then G H. These statements extend results due to Beers-Richman-Walker (1983), and also partially solve a well-known question raised by May in 1979. 相似文献
209.
For integral table algebras with integral table basisT, we can consider integralR-algebraRT over a subringR of the ring of the algebraic integers. It is proved that anR-algebra isomorphism between two integral table algebras must be an integral table algebra isomorphism if it is compatible
with the so-called normalizings of the integral table algebras 相似文献
210.