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111.
This contribution deals with developments in the history of philosophy, logic, and mathematics during the time before and up to the beginning of fuzzy logic. Even though the term “fuzzy” was introduced by Lotfi A. Zadeh in 1964/1965, it should be noted that older concepts of “vagueness” and “haziness” had previously been discussed in philosophy, logic, mathematics, applied sciences, and medicine. This paper delineates some specific paths through the history of the use of these “loose concepts”. Vagueness was avidly discussed in the fields of logic and philosophy during the first decades of the 20th century—particularly in Vienna, at Cambridge and in Warsaw and Lvov. An interesting sequel to these developments can be seen in the work of the Polish physician and medical philosopher Ludwik Fleck.Haziness and fuzziness were concepts of interest in mathematics and engineering during the second half of the 1900s. The logico-philosophical history presented here covers the work of Bertrand Russell, Max Black, and others. The mathematical–technical history deals with the theories founded by Karl Menger and Lotfi Zadeh. Menger's concepts of probabilistic metrics, hazy sets (ensembles flous) and micro-geometry as well as Zadeh's theory of fuzzy sets paved the way for the establishment of soft computing methods using vague concepts that connote the nonexistence of sharp boundaries. 相似文献
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Rudolf Berghammer 《Acta Informatica》2008,45(3):211-236
Relation algebra is well suited for dealing with many problems on ordered sets. Introducing lattices via order relations,
this suggests to apply it and tools for its mechanization for lattice-theoretical problems, too. We combine relation algebra
and the BDD-based specific purpose Computer Algebra system RelView to solve some algorithmic problems on orders and lattices and to visualize their solutions. 相似文献
116.
We present relation-algebraic specifications of injective embedding mappings and splittings of partial equivalence relations
and show in each case that the axioms characterize these constructions up to isomorphism, i.e., in an essentially unique way.
Based on the specifications, we develop a relational program for computing splitting and demonstrate some applications. The
examples originate from a relation-algebraic treatment of processes, graph theory, and the decomposition of specific relations. 相似文献
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Two major planning problems are encountered when designing a cellular radio network. The initial question is where to locate the base transmitter stations such that full coverage is achieved at low interference. This is relevant for frequency division (FDMA) as well as code division multiple access (CDMA) technology. If the locations of base stations are given, then for an FDMA-system frequencies have to be assigned such that there is a sufficient number of channels per cell available at a low total interference level. Since cell site selection and frequency allocation have mutual influences on each other, the ultimate goal is to deal with both problems in a single design step. The main intention of this paper is to model the above planning issues as linear integer programs, and to discuss solution methods for the corresponding NP-hard problems. According to their increasing complexity we proceed from channel allocation via cell site selection to an integrated single setup. 相似文献
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