The main contribution of this work has been the establishment of an institution independent theory of composition of hierarchic specifications. Hierarchic specifications consist of formulas (“defaults”) from an underlying logic (institution), organized by priority levels (related by a partial order). These formulas can be defeated when in contradiction with more reliable information (at more im...

Converging evidence from anatomical studies (Maunsell, 1983) and functional analyses (Hubel & Wisesel, 1968) of the nervous system suggests that the feed-forward pathway of the mammalian perceptual system follows a largely hierarchic organization scheme. This may be because hierarchic structures are intrinsically more viable and thus more likely to evolve (Simon, 2002). But it may also be becau...

ALTHOUGH SYNTHETIC ANALOGS of proteins might be developed ultimately, Flory’s succinct statement accurately summarizes the remarkable behavior of globular proteins. Today, an intense search is being made for the principles that guide the folding process. Although the work began with experimental studies (see Box 1), it has become increasingly clear that these results cannot be interpreted succe...

locating landfills in urban areas is one of the most important issues in urban planning because of the effect on economy, ecology, and environment, therefore the right management and principled landfilling of solid waste is the major concern all over the world especially in the developed countries. in locating landfills, different criteria should be considered. in the present study, locating si...

just like any other process, vaccine manufacturing procedures are defined as a series of interrelated functions and activities using a variety of specified actions and equipment designed to produce a defined product. to assure the reproducibility and consistency of such processes, they must be carried out using validated equipment and under the established procedures that meet all the acceptanc...

We present an abstract specification theory that formalizes non-monotonic composition constructs from specification languages providing explicit non-monotonic mechanisms as a specification facility. This theory generalizes the institutional framework from Goguen and Burstall by adding defeasibility mechanisms to a given institution. The denotation of a specification module consists of defaults ...