Báo cáo toán học: "Switching of edges in strongly regular graphs " ppsx

... then switching of edges in a strongly regular graph may produce another strongly regular graph. If switching of edges in a regular graph produces a regular graph then the corresponding partition ... merging of classes in the scheme of 2-orbits of this action of H. It was clear from the beginning that one of the resulting schemes will give the graph Θ, howev...

Ngày tải lên: 07/08/2014, 07:21

... the goal and scope for energy accounting in conventional agriculture in Austria In line wi th the goal definition and principles of LCA (ISO, 2006) and following the approach taken by Hüls- bergen ... of plant and machin- ery used to cultivate cropland and maintain livestock housing, and indirectly, in the form of manufactured mineral fertilizers and pesticides. The level of e...

Ngày tải lên: 20/06/2014, 21:20

... any pair of integers m<nin the interval I, there exists some set of integers in the interval J whose product is mn times a square (of an integer). ii) Suppose that the interval I contains a square. ... product of some subset of the integers in I equals N times a square, then there is some set of integers in the interval J whose product equals N times a square. Proof: i) Su...

Ngày tải lên: 07/08/2014, 06:22

... class="bi x0 y0 w1 h 1" alt =""

Ngày tải lên: 05/08/2014, 15:21

... All five of the long-lived mutants had increased pools of amino acids, especially of the branched-chain amino acids isoleucine, leucine and valine, together with phenylalanine and tyrosine. A ... to threefold. daf-2 and age-1 specify steps in the insulin/ insulin-like signaling (IIS) pathway, thereby in uencing metabolism. IIS signaling inactivates the FOXO (forkhead box O) tran...

Ngày tải lên: 06/08/2014, 19:21

... C(e)thecolor of the the electronic journal of combinatorics 12 (2005), #R33 1 [6] P. Erd˝os and Zs. Tuza, Rainbow Hamiltonian paths and canonically colored sub- graphs in infinite complete graphs, ... Voigt, Minimal colorings for properly colored subgraphs, Graphs and Combin. 12 (1996), 345–360. the electronic journal of combinatorics 12 (2005), #R33 32 Then, P  is a heterochroma...

Ngày tải lên: 07/08/2014, 13:21

... by considering another packing pattern. 1 Introduction The search of the densest packing of n non-overlapping equal disks in a compact set of the plane is a classical problem of discrete geometry. An introductory ... displacing the n remaining congruent disks which grow continuously and do not overlap. During a weak generation of Q K n from Q K m , we consider the contact graphs...

Ngày tải lên: 07/08/2014, 21:21

... (D i ) i∈I of subsets of E thin if no edge lies in D i for in nitely many indices i. Let the (thin) sum  F of this family be the set of all edges that lie in D i for an odd number of indices i, ... closed, every point in P \ C is contained in a C-arc in P. Suppose no C-arc in P is a shortcut of C. We can find a family (W i ) i∈N of countably many internally disjoi...

Ngày tải lên: 08/08/2014, 01:20

... t)|Y 0 |. By the induction hypothesis, G 0 has a K a−1,t -minor, in which each of the branch sets corresponding to the vertices in the partite set of order t in K a−1,t is a singleton of X 0 . Since y 0 is ... − a + 1). Then G has a K a,t -minor, in which each of the branch sets corresponding to the vertices in the partite set of order t of K a,t is a singleton of X....

Ngày tải lên: 08/08/2014, 14:23

... electronic journal of combinatorics 12 (2005), #R42 1 Proof. Since v ≥ 19, there are at least nine blocks containing x. Also X has at most six points not in any of the blocks of X that contain x. Hence ... least nine blocks containing y and, since X contains at most eight points, there is at least one block (containing y) that is disjoint from X . Theorem 4.1 The block intersection gr...

Ngày tải lên: 07/08/2014, 13:21