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981.
《组合设计杂志》2018,26(4):154-173
Given a combinatorial design with block set , the block‐intersection graph (BIG) of is the graph that has as its vertex set, where two vertices and are adjacent if and only if . The i‐block‐intersection graph (i‐BIG) of is the graph that has as its vertex set, where two vertices and are adjacent if and only if . In this paper, several constructions are obtained that start with twofold triple systems (TTSs) with Hamiltonian 2‐BIGs and result in larger TTSs that also have Hamiltonian 2‐BIGs. These constructions collectively enable us to determine the complete spectrum of TTSs with Hamiltonian 2‐BIGs (equivalently TTSs with cyclic 2‐intersecting Gray codes) as well as the complete spectrum for TTSs with 2‐BIGs that have Hamilton paths (i.e. for TTSs with 2‐intersecting Gray codes). In order to prove these spectrum results, we sometimes require ingredient TTSs that have large partial parallel classes; we prove lower bounds on the sizes of partial parallel classes in arbitrary TTSs, and then construct larger TTSs with both cyclic 2‐intersecting Gray codes and parallel classes. 相似文献
982.
Murray Bremner 《代数通讯》2018,46(6):2396-2404
The commutator [a,b] = ab?ba in a free Zinbiel algebra (dual Leibniz algebra) is an anticommutative operation which satisfies no new relations in arity 3. Dzhumadildaev discovered a relation T(a,b,c,d) which he called the tortkara identity and showed that it implies every relation satisfied by the Zinbiel commutator in arity 4. Kolesnikov constructed examples of anticommutative algebras satisfying T(a,b,c,d) which cannot be embedded into the commutator algebra of a Zinbiel algebra. We consider the tortkara triple product [a,b,c] = [[a,b],c] in a free Zinbiel algebra and use computer algebra to construct a relation TT(a,b,c,d,e) which implies every relation satisfied by [a,b,c] in arity 5. Thus, although tortkara algebras are defined by a cubic binary operad (with no Koszul dual), the corresponding triple systems are defined by a quadratic ternary operad (with a Koszul dual). We use computer algebra to construct a relation in arity 7 satisfied by [a,b,c] which does not follow from the relations of lower arity. It remains an open problem to determine whether there are further new identities in arity n≥9. 相似文献
983.
In this paper, we first introduce a special structure that allows us to construct a large set of resolvable Mendelsohn triple systems of orders 2q + 2, or LRMTS(2q + 2), where q = 6t + 5 is a prime power. Using a computer, we find examples of such structure for t C T = {0, 1, 2, 3, 4, 6, 7, 8, 9, 14, 16, 18, 20, 22, 24}. Furthermore, by a method we introduced in [13], large set of resolvable directed triple systems with the same orders are obtained too. Finally, by the tripling construction and product construction for LRMTS and LRDTS introduced in [2, 20, 21], and by the new results for LR-design in [8], we obtain the existence for LRMTS(v)and LRDTS(v), where v = 12(t + 1) mi≥0(2.7mi+1)mi≥0(2.13ni+1)and t∈T,which provides more infinite family for LRMTS and LRDTS of even orders. 相似文献
984.
提出应变能集中这一概念,对三晶体中三晶交线附近的弹性应变能的集中特性进行了计算,发现当加载方向平行于三晶交线时,三晶交线附近有弹性应变能集中,但是集中程度不是很高,当加载方向垂直于三晶交线时,根据三晶体中组元晶体的相对位置的不同和取向的不同,三晶交线附近或者没有弹性应变能集中,或者有弹性应变能集中,而且在一些情况下与平行于三晶交线方向加载的情况相比,弹性应变能的集中程度要高很多。 相似文献
985.
In this paper, we consider nonlinear evolution problems, defined on an evolution triple of spaces, driven by a nonmonotone operator, and with a perturbation term which is multivalued. We prove existence theorems for the cases of a convex and of a nonconvex valued perturbation term which is defined on all of T × H or only on T × X with values in H or even in X* (here X - H - X* is the evolution triple). Also, we prove the existence of extremal solutions, and for the “monotone” problem we have a strong relaxation theorem. Some examples of nonlinear parabolic problems are presented. 相似文献
986.
期权定价的新型三叉树方法 总被引:1,自引:0,他引:1
讨论了普通二叉树模型定价公式的缺陷,在新型二叉树定价模型的基础上利用原点矩和中心矩的关系得出新型三叉树定价模型公式,并且证明该三叉树模型下期权价格满足的方程是B-S方程在Δt上的一阶近似. 相似文献
987.
对完全0-单半群上的相容组条件进行简化,引入完全单半群上同余结的概念,并给出相容组与同余结的应用. 相似文献
988.
本文研究了δJordan-李三系上带有权λ的k-阶广义导子的相关问题.通过计算,得到了每一个δJordan-李三系上带有权λ的k-阶Jordan三角θ-导子都是一个带有权λ的k-阶θ-导子.在定义下,给出了带有权λ的k-阶Jordan三角θ-导子的另一种等价形式.同时,建立了带有权λ的k-阶广义(θ,ϕ)-导子和Rota-BaxterδJordan-李三系上带有权λ的Rota-Baxter算子的遗传性质,得到了每一个Rota-BaxterδJordan-李代数能看成一个Rota-BaxterδJordan-李三系的结论. 相似文献
989.
990.
Serkan Güldal 《哲学杂志》2020,100(5):642-657
ABSTRACTThe edge and surface antiferromagnetic properties of the ABO3 perovskite-type nanoparticle and their components (A, B and O) are investigated through the Effective Field Theory developed by Kaneyoshi. It is found that the Edge AntiFerroMagnetism (EAFM) causes a decrease in the Curie temperature and separation in the magnetizations. However, the Surface AntiFerroMagnetism (SAFM) causes a compensation behaviour (TComp?=?1.23) in the total magnetisation of the ABO3 perovskite-type nanoparticle. The magnetisation of the central B component has been affected by the edge antiferromagnetism more strongly than by the surface antiferromagnetism. Moreover, coercivity (Hc) and remanence magnetizations (Mr) decrease for the EAFM, but they increase for the SAFM. Triple hysteresis behaviour is obtained for the SAFM. Therefore, it is suggested that there is a strong relationship between the compensation behaviour and the triple hysteresis behaviour. 相似文献