In this study two actual types of problems are considered and solved: 1) determining the maximum common connected fragment of the T-tree (T-directed tree) which does not change with time; 2) determining all maximum common connected fragments of the T-tree (T-directed tree) which do not change with time. The choice of the primary study of temporal directed trees and trees is justified by the wid...

Within the natural language information system PLIDIS [6] a semantic processor was implemented for the translation of syntactically analyzed sentences into expressions of a predicate calculus-orlented internal representation language. This semantic processor was designed according to a translation grammar defined by Wulz [8], which is similar to the transformation grammar introduced by Chomsky ...

* Partially supported by NSF under Grant No. DMS-9701598. † Research partially supported by NSF under Grant No. DMS-9401981 and by DIMACS Center, Rutgers University, New Brunswick, NJ 08903. ‡ Partially supported by ONR under Contract No. N00014-97-1-0512. §Partially supported by NSF under Grant No. DMS-9623031, by NSA under Contract No. MDA904-98-1-0517, and by DIMACS Center, Rutgers Universit...

In [1] Johnson, Robertson, Seymour and Thomas define the notion of directed tree-width dtw(D) of a directed graph D. They ask whether dtw(D) ≥ k− 1 implies that D has a haven of order k. A negative answer is given. Furthermore they define a generalisation of the robber and cops game of [3] to digraphs. They ask whether it is true that if k cops can catch the robber on a digraph, then they can d...

Connectivity and reachability on temporal networks, which can describe the spreading of a disease, decimation information or accessibility public transport system over time, have been among main contemporary areas study in complex systems for last decade. However, while isotropic percolation theory successfully describes connectivity static similar description has not yet developed networks. He...

1 Graph streams have been studied extensively, such as for data mining, while fairly limitedly for visualizations. Recently, edge bundling promises to diminish visual clutter in large graph visualizations, though mainly focusing on static graphs. This paper presents a new framework, namely StreamEB, for edge bundling of graph streams, which integrates temporal, neighbourhood, data-driven and sp...

Although the structure of simple actions can be captured by rigid grids [3] or by sequences of short temporal parts [2], activities are composed of a variable number of sub-events connected by more complex spatio-temporal relations. In this paper, we learn how to automatically represent activities as a hierarchy of mid-level motion components in order to improve activity classification in real-...