Showing papers by "Marco Ronchetti published in 1996"

Local icosahedral structures in binary-alloy clusters from molecular-dynamics simulation

Abstract: We investigate the structure of 13-particle clusters in binary alloys for various size ratios and different concentrations via molecular-dynamics simulation. Our goal is to predict which systems are likely to form local icosahedral structures when rapidly supercooled from the melt. We calculate the energy spectrum of the minimal energy structures, and characterize all detected minima from both their relative probability and a structural point of view. We identify regions in our parameter space where the icosahedral structure is dominant (like in the corresponding monatomic case), regions where the icosahedral structure disappears, and others where icosahedral structures are present but not dominant. Finally, we compare our results with simulations reported in the literature and performed on extended binary systems with various size ratios and at different concentrations. \textcopyright{} 1996 The American Physical Society.

A taxonomy for identifying a software component for uncertain and partial specifications

Abstract: Software maintenance and reuse depends on a system for inserting and subsequently searching for software objects in a repository. A number of classical methodologies from library and information science exist and seem appropriate to this purpose. All of these methodologies bring to a high degree of uncertainty both in the specification of the searched objects and in the way an object is classified. To give a basis for a better understanding of these approximations, this paper presents a formal view of the basic li.brary science methodologies for indexing and classification. The formalization permits the computational complexity of the different methodologies to be compared. In considering the special needs for extensions to the methodologies to support software reuse, a strategy based upon a hybridization of the simplest three methodologies is proposed rather than using or developing more complex methodologies. The authors conclude that some extensions oriented towards the inevitable informal human side of the process may be necessary based on a domain analysis of the environment in which such methodologies must operate, but these extensions should be accounted for by engineering the proper elements into a formal framework which will "Permission to make digital/hard copy of all or part of this material without fee is granted provided that copies are not made or distributed for profit or commercial advantage, the ACM copyright/server notice, the title of the publication and its date appear, and notice is given that copying is by permission of the Association for Computing Machinery, Inc.(ACM). To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee." © 1996 ACM0-89791-820-7 96 0002 3.50 support software reuse and reusability.