Abstract
Alsina, Frank, and Schweizer posed a question whether a non-trivial convex combination of triangular norms can ever be a triangular norm. In this paper we deal with the class of strict t-norms with well-defined first partial derivatives along their zero borders. We show that the answer to the question is negative for certain couples of such t-norms and we state out possible further research.
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Acknowledgments
The author would like to thank the anonymous referee for valuable comments. The author was supported by Czech Science Foundation under Project 201/07/1136.
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Petrík, M. Convex combinations of strict t-norms. Soft Comput 14, 1053–1057 (2010). https://doi.org/10.1007/s00500-009-0484-3
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DOI: https://doi.org/10.1007/s00500-009-0484-3