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51.
We base ourselves on the construction of the two-dimensional random interlacements (Comets et al., 2016) to define the one-dimensional version of the process. For this, we consider simple random walks conditioned on never hitting the origin. We compare this process to the conditional random walk on the ring graph. Our results are the convergence of the vacant set on the ring graph to the vacant set of one-dimensional random interlacements, a central limit theorem for the interlacements’ local time and the convergence in law of the local times of the conditional walk on the ring graph to the interlacements’ local times. 相似文献
52.
We construct a connected cubic nonnormal Cayley graph on for each integer and determine its full automorphism group. This is the first infinite family of connected cubic nonnormal Cayley graphs on nonabelian simple groups. 相似文献
53.
Let be a graph and let be a group of automorphisms of . The graph is called -normal if is normal in the automorphism group of . Let be a finite non-abelian simple group and let with . In this paper we prove that if every connected pentavalent symmetric -vertex-transitive graph is -normal, then every connected pentavalent symmetric -vertex-transitive graph is -normal. This result, among others, implies that every connected pentavalent symmetric -vertex-transitive graph is -normal except is one of 57 simple groups. Furthermore, every connected pentavalent symmetric -regular graph is -normal except is one of 20 simple groups, and every connected pentavalent -symmetric graph is -normal except is one of 17 simple groups. 相似文献
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56.
在Girard Quantale中引入了模糊滤子和模糊关联滤子的概念,研究了Girard Quantale中模糊滤子和模糊关联滤子的一些性质,给出了Girard Quantale中模糊关联滤子的若干等价刻画,探讨了模糊关联滤子与模糊布尔滤子之间的关系. 相似文献
57.
《Journal of Macromolecular Science: Physics》2013,52(2):385-403
Abstract Mechanical behavior of bulk semicrystalline poly(ethylene terephthalate) (PET) processed through simple shear is investigated. The equal channel angular extrusion (ECAE) process was used to achieve the simple shear condition. The PET samples were processed in one and two ECAE passes in the same direction, with the sample rotated 180° about the extrusion axis for the second pass. Microstructural features at the nanometer and micrometer scales were studied by small‐angle x‐ray scattering (SAXS) and scanning electron microscopy (SEM). SAXS results showed that at the nanometer scale, two types of lamellar orientations are induced in both samples, but with different extents of orientation. In the ECAE‐oriented PET structures on the micrometer scale, as revealed by SEM, are well‐defined macrofibrils. However, the fibrillar structures in the sample extruded once are more oriented than those in the sample extruded twice. Fractography investigations suggest that the ECAE‐induced fibrillar structure and stretched amorphous chains are responsible for the change in mechanical properties. 相似文献
58.
The negative viscosity of a colloidal dispersion composed of ferromagnetic rod-like particles, which have a magnetic moment normal to the particle axis, have been investigated. A simple shear flow problem has been treated to clarify the particle orientational distribution and rheological properties of such a semi-dense dispersion, under circumstances of an external magnetic field applied in the direction normal to the shear plane of a simple shear flow. The results obtained here are summarized as follows. For the cases of a very strong magnetic field and magnetic interactions between particles, the magnetic moment of the rod-like particles is significantly restricted in the magnetic field direction, so that the particle approximately aligns in the shear flow direction. Also, the particle can easily rotate around the axis of the cluster almost freely even in a simple shear flow. Characteristic orientational properties of the particle cause negative viscosity, as in the previous study for a dilute dispersion. However, magnetic particle-particle interactions have a function to make such negative viscosity decrease. 相似文献
59.
Letitia Golubitsky 《代数通讯》2013,41(6):2091-2105
It is well known that the Eulerian polynomials, which count permutations in S n by their number of descents, give the h-polynomial/h-vector of the simple polytopes known as permutohedra, the convex hull of the S n -orbit for a generic weight in the weight lattice of S n . Therefore, the Eulerian polynomials give the Betti numbers for certain smooth toric varieties associated with the permutohedra. In this article we derive recurrences for the h-vectors of a family of polytopes generalizing this. The simple polytopes we consider arise as the orbit of a nongeneric weight, namely, a weight fixed by only the simple reflections J = {s n , s n?1, s n?2,…, s n?k+2, s n?k+1} for some k with respect to the A n root lattice. Furthermore, they give rise to certain rationally smooth toric varieties X(J) that come naturally from the theory of algebraic monoids. Using effectively the theory of reductive algebraic monoids and the combinatorics of simple polytopes, we obtain a recurrence formula for the Poincaré polynomial of X(J) in terms of the Eulerian polynomials. 相似文献
60.
Surjeet Kour 《代数通讯》2013,41(11):4100-4110
It is shown that the derivation y r ? x + (xy s + g)? y , where 0 ≤ r < s are integers, is a simple derivation of k[x, y], the polynomial ring in two variables over a field k of characteristic zero. 相似文献