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91.
In this work we compute the thermodynamic properties of the 3-satisfiability problem in the infinite connectivity limit. In this limit the computation can be strongly simplified and the thermodynamic properties can be obtained with a high accuracy. We find evidence for a continuous replica symmetry breaking in the region of high number of clauses, >c. 相似文献
92.
We study Dedekind complete commutative BCK-algebras with the relative cancellation property and their connection with corresponding universal groups. We shall characterize Dedekind orthogonally complete atomic and Archimedean BCK-algebras, generalizing results of Jakubík known for MV-algebras. Finally, we characterize those Dedekind complete and atomic commutative BCK-algebras that are isomorphic to direct products of basic BCK-chains, generalizing a result of Cignoli for MV-algebras. 相似文献
93.
Ralf Kemper 《Proceedings of the American Mathematical Society》2000,128(3):709-712
It is an open question as to whether every left coherent ring satisfying the intersection property for finitely generated left ideals of is a right-product-trace-ring or not. is a right-product-trace-ring iff every product of trace-right--modules (= universally torsionless-right--modules) is a trace-right--module. This question is shown to have a negative answer. Furthermore, looking at all valuation domains, the complete product-trace-rings, the product-trace-rings and the product-content-rings are characterized.
94.
设计了一种棋盘格子复式晶格的二维光子晶体:在二维正方形格子中,把截面为正方形的柱子旋转45°,同时在每个原胞中心引入一个圆形截面的柱子构成的光子晶体结构. 用平面波展开计算棋盘格子复式晶格的完全光子带隙,结果表明:棋盘格子复式晶格的完全光子带隙的Δω/ω比值几乎是普通棋盘格子的5倍,完全光子带隙的个数也增加. 与其他复式结构相比较,发现其最佳的Δω/ω比值是一类粗锐复合结构光子晶体的2.1倍.
关键词:
二维光子晶体
复式晶格
完全光子带隙 相似文献
95.
S. Ya. Grinshpon 《代数通讯》2013,41(11):4273-4282
We study primary groups containing proper fully invariant subgroups isomorphie to the group. The admissable sequence of Ulm–Kaplansky invariants for primary groups is introduced. Using these sequences, If-groups are described in the classes of seperable and periodically complete groups. 相似文献
96.
We show that every plane graph with maximum face size four in which all faces of size four are vertex‐disjoint is cyclically 5‐colorable. This answers a question of Albertson whether graphs drawn in the plane with all crossings independent are 5‐colorable. © 2009 Wiley Periodicals, Inc. J Graph Theory 64: 184–205, 2010 相似文献
97.
State tomography on qubit pairs is routinely carried out by measuring the two qubits separately, while one expects a higher efficiency from tomography with highly symmetric joint measurements of both qubits. Our numerical study of simulated experiments does not support such expectations. 相似文献
98.
W.-Q. Chen 《Archive of Applied Mechanics (Ingenieur Archiv)》1999,69(7):455-464
Summary Utilizing the general solution of transversely isotropic piezoelectricity, the paper analyzes the problem of an inclined
rigid circular flat punch indenting a transversely isotropic piezoelectric half-space. The potential theory method is employed
and generalized to take into account the effect of the electric field in piezoelectric materials. Assuming that the punch
is maintained at a constant electric potential, exact expressions for the elastoelectric field are derived in terms of elementary
functions. It is noted that the solution corresponding to a flat circular punch centrally loaded by a concentrated force can
be obtained as a special case.
Received 15 December 1998; accepted for publication 9 March 1999 相似文献
99.
We analyse the mixing time of Markov chains using path coupling with stopping times. We apply this approach to two hypergraph problems. We show that the Glauber dynamics for independent sets in a hypergraph mixes rapidly as long as the maximum degree Δ of a vertex and the minimum size m of an edge satisfy m ≥ 2Δ + 1. We also show that the Glauber dynamics for proper q‐colorings of a hypergraph mixes rapidly if m ≥ 4 and q > Δ, and if m = 3 and q ≥ 1.65Δ. We give related results on the hardness of exact and approximate counting for both problems. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008 相似文献
100.