Báo cáo toán hoc:"A New Lower Bound on the Density of Vertex Identifying Codes for the Infinit" doc

... more vertices). Proposition 1. The density of every vertex identifying code for the infinite hexagonal grid is at least 2/5. Proof: Our proof is by the discharging method. Thus, D must contain at least 2/5 of the ... elsewhere. Theorem 1. The density of every vertex identifying code for the infinite hexagonal grid is at least 12/29. Proof: Our proof is by disch...

Ngày tải lên: 08/08/2014, 01:20

... components of G  [S  ], other than the P 2 -component consisting of the two degree-2 vertices in the copy of X and, if N ∗ uv = ∅, the P 1 -component consisting of the degree-2 vertex in the copy of ... neighbor of the link vertex in the attached copy of Z and the link vertex in the attached copy of X. Deleting these three vertices in the attache...

Ngày tải lên: 07/08/2014, 15:23

... whether a superlinear lower bound exists for M(n, n). The quantity M(n, n) gives an upper bound for the largest convexly independent subset of P ⊕ P, and it is related to the convex dimension of ... part of the work has been done at the 12th Korean Workshop on Computational Geometry, June 2009 and at the 7th Gremo Workshop on Open Problems, July 2009. The aut...

Ngày tải lên: 08/08/2014, 11:20

... satisfying the Newton inequalities (2) of order m. I.e. we dropped the condition of nonnegativity from the definition of ultra-logconcavity. It is not true that c = a  a satisfies the Newton inequalities ... (but powerful) representation of the convolution in terms of the product of the corresponding poly- nomials. The original Liggett’s proof does not rely on thi...

Ngày tải lên: 07/08/2014, 21:21

... lower bounds, but also provides certificates for all the other proved and currently known lower bounds for Van der Waerden numbers with even r. The only exception is the lower bound of the Van ... proof of the Szemer´edi theorem [17] on arithmetic progressions. Still, there is a significant gap between the upper and lower bounds on the Van der Waerden numbers...

Ngày tải lên: 07/08/2014, 15:22

... condition from three to two, but restrict the structure of the graph the electronic journal of combinatorics 18 (2011), #P12 6 that is, F consists of the 28035 non-isomorphic graphs in the family ... graph in the family G 2conn . The family G 2conn we have constructed is a family of 2-connected graphs that achieve equality in the bound of Theorem 1. We remark, howe...

Ngày tải lên: 08/08/2014, 12:23

... organisms. The objec- tive of the ongoing research is to extend and improve the current experimental design based on the knowledge of the presented proof -of- concept study [13]. During the next ... bear the risk of eroding sediments in rivers, reservoirs, harbour basins or estuaries. One of the key concerns associated with these erosion processes is the re-mobilis...

Ngày tải lên: 20/06/2014, 21:20

Ngày tải lên: 05/08/2014, 09:46

Ngày tải lên: 05/08/2014, 15:20

... family of subsets of a n-set and f(k,n) to be the size of the largest possible cancellative family of k-subsets of a n-set. Note the condition A ∪ B = A ∪ C ⇒ B = C isthesameastheconditionBC ... than (1) for m ≥ 8. So the Bollobas conjecture fails for k ≥ 10. The idea of the above construction which improves on products of H 3 can be applied to products of o...

Ngày tải lên: 07/08/2014, 06:20