It is known that by iterating the look-ahead tree languages for deterministic topdown tree automata, more and more powerful recognizing devices are obtained. Let DR0 = DR, where DR is the class of all tree languages recognizable by deterministic top-down tree automata, and let, for n 1, DRn be the class of all tree languages recognizable by deterministic top-down tree automata with DRn 1 lookah...

International Patent Classification (IPC) is a standard taxonomy or hierarchy maintained by WIPO (World Intellectual Property Organization). Using this standard hierarchy, patents are classified using machine learning techniques. The first sets of experiments investigate the effect on classification performance at different levels (section, class, subclass and main group level) of IPC hierarchy...

Working Paper Series Abstract Hierarchy is a generic structure in which levels are asymmetrically ordered. In an industry setting, classic supply chains display strict hierarchy, whereas clusters of firms have linkages going in many different directions. Previous theory has often assumed the existence of the hierarchical relationships among firms and empirical work has focused on a single level...

The analytic hierarchy process (AHP) is used as a modelling and solution tool for multicriteria decision making. The AHP breaks a problem down and then aggregates the solutions of all the subproblems into a conclusion. By breaking it down, the AHP utilizes the human ability to make sound judgements about small problems. (see Saaty 1991 and Saaty 1996.) The most creative part of decision making ...

An incrementally modular abstraction hierarchy is known to effectively linearize cyberworlds and virtual worlds which are combinatorially exploding and hardly managed. It climbs down from general level to specific model preserving the higher level modules as invariants. It not only prevents the combinatorial explosion but also benefits the reuse, development, testing and validation of cyberworl...

We investigate the quark masses and mixings by including vector-like down-type quark singlets in universality of strength for Yukawa couplings (USY). In contrast with the standard model with USY, the sufficient CP violation is obtained for the Cabibbo-Kobayashi-Maskawa matrix through the mixing between the ordinary quarks and quark singlets. The top-bottom mass hierarchy mt ≫ mb also appears na...