41,336 research outputs found
Modelling multi-scale microstructures with combined Boolean random sets: A practical contribution
Boolean random sets are versatile tools to match morphological and topological properties of real structures of materials and particulate systems. Moreover, they can be combined in any number of ways to produce an even wider range of structures that cover a range of scales of microstructures through intersection and union. Based on well-established theory of Boolean random sets, this work provides scientists and engineers with simple and readily applicable results for matching combinations of Boolean random sets to observed microstructures. Once calibrated, such models yield straightforward three-dimensional simulation of materials, a powerful aid for investigating microstructure property relationships. Application of the proposed results to a real case situation yield convincing realisations of the observed microstructure in two and three dimensions
Three Puzzles on Mathematics, Computation, and Games
In this lecture I will talk about three mathematical puzzles involving
mathematics and computation that have preoccupied me over the years. The first
puzzle is to understand the amazing success of the simplex algorithm for linear
programming. The second puzzle is about errors made when votes are counted
during elections. The third puzzle is: are quantum computers possible?Comment: ICM 2018 plenary lecture, Rio de Janeiro, 36 pages, 7 Figure
Document Retrieval, Automatic
Document Retrieval is the computerized process of producing a relevance ranked list of documents in response to an inquirer’s request by comparing their request to an automatically produced index of the documents in the system. Everyone uses such systems today in the form of web-based search engines. While evolving from a fairly small discipline in the 1940s, to a large, profitable industry today, the field has maintained a healthy research focus, supported by test collections and large-scale annual comparative tests of systems. A document retrieval system is comprised of three core modules: document processor, query analyzer, and matching function. There are several theoretical models on which document retrieval systems are based: Boolean, Vector Space, Probabilistic, and Language Model
Save up to 99% of your time in mapping validation
Identifying semantic correspondences between different vocabularies has been recognized as a fundamental step towards achieving interoperability. Several manual and automatic techniques have been recently proposed. Fully manual approaches are very precise, but extremely costly. Conversely, automatic approaches tend to fail when domain specific background knowledge is needed. Consequently, they typically require a manual validation step. Yet, when the number of computed correspondences is very large, the validation phase can be very expensive. In order to reduce the problems above, we propose to compute the minimal set of correspondences, that we call the minimal mapping, which are sufficient to compute all the other ones. We show that by concentrating on such correspondences we can save up to 99% of the manual checks required for validation
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