We introduce a newnotion called a quasi-Feistel cipher, which is a generalization of the Feistel cipher, and contains the Lai–Massey cipher as an instance. We show that most of the works on the Feistel cipher can be naturally extended to the quasi-Feistel cipher. From this, we give a new proof for Vaudenay’s theorems on the security of the Lai–Massey cipher, and also we introduce for Lai–Massey...

In the crystal structure of the title compound, C(7)H(7)N(2) (+)·Br(-), the cations are associated into inversion dimers through weak pairwise C-H⋯N hydrogen bonds. The dimers further form stepped sheets via weak pairwise C-H⋯N hydrogen bonds. In the sheets, the spacing between the mean planes of the laterally displaced aromatic rings in adjacent dimers is 1.124 (6) Å. Three N-H⋯Br inter-action...

Let G be a 2-connected claw-free graph on n vertices, and let H be a subgraph of G. We prove that G has a cycle containing all vertices of H whenever a3(H) 5 K(G), where a 3 ( H ) denotes the maximum number of vertices of H that are pairwise at distance at least three in G, and K(G) denotes the connectivity of G. This result is an analog of a result from the thesis of Fournier, and generalizes ...

A topological graph is k-quasi-planar if it does not contain k pairwise crossing edges. An old conjecture states that for every fixed k, the maximum number of edges in a k-quasi-planar graph on n vertices is O(n). Fox and Pach showed that every kquasi-planar graph with n vertices and no pair of edges intersecting in more than O(1) points has at most n( log n log k ) k) edges. We improve this up...

A topological graph is quasi-planar, if it does not contain three pairwise crossing edges. Agarwal et al. [2] proved that these graphs have a linear number of edges. We give a simple proof for this fact that yields the better upper bound of 8n edges for n vertices. Our best construction with 7n−O(1) edges comes very close to this bound. Moreover, we show matching upper and lower bounds for seve...

A digraph D is called quasi-transitive if for any triple x, y, z of distinct vertices of D such that (x, y) and (y, z) are arcs of D there is at least one arc from x to z or from z to x. A minimum path factor of a digraph D is a collection of the minimum number of pairwise vertex disjoint paths covering the vertices of D. J. Bang-Jensen and J. Huang conjectured that there exist polynomial algor...

This paper presents a new asymptotically exact lower bound on pairwise error probability of a space-time code as well as an example code that outperforms the comparable orthogonal-design-based space-time (ODST) code. Also contained in the paper are some observations relating to exact pairwise error probability, signal design guidelines and simplicity of the ODST code receiver. Keywords— Space-t...

We make use of a set of text analysis tools, primarily based on Latent Semantic Indexing, to study the dynamics of memes on the Net. Our analysis discovers replicating memes within posts to the USENET News (or NetNews) system. We cluster the posts to NetNews into clouds within a conceptual sequence space; these clusters describe quasispecies. We then go on to study the pairwise interactions bet...

A graph drawn in the plane is called k-quasi-planar if it does not contain k pairwise crossing edges. It has been conjectured for a long time that for every fixed k, the maximum number of edges of a k-quasi-planar graph with n vertices is O(n). The best known upper bound is n(logn) . In the present note, we improve this bound to (n logn)2 c k (n) in the special case where the graph is drawn in ...

in this study, we investigate the further properties of quasi irresolute topological groupsdened in [20]. we show that if a group homomorphism f between quasi irresolute topologicalgroups is irresolute at eg, then f is irresolute on g. later we prove that in a semi-connectedquasi irresolute topological group (g; ; ), if v is any symmetric semi-open neighborhood ofeg, then g is generated by v...