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71.
Monica Bianchi Alessandra Cornaro Anna Torriero 《Discrete Applied Mathematics》2013,161(16-17):2731-2739
This paper presents a unified approach for localizing some relevant graph topological indices via majorization techniques. Using this method, we derive old and new bounds. Numerical examples are provided showing how current results in the literature could be improved. 相似文献
72.
United States and South Korean citizens’ interpretation and assessment of COVID-19 quantitative data
We investigate United States and South Korean citizens’ mathematical schemes and how these schemes supported or hindered their attempts to assess the severity of COVID-19. We selected web and media-based COVID-19 data representations that we hypothesized citizens would interpret differently depending on their mathematical schemes. We included items that we conjectured would be easier or more difficult to interpret with schemes that prior research had reported were more or less productive, respectively. We used the representations during clinical interviews with 25 United States and seven South Korean citizens. We illustrate that citizens’ mathematical schemes (as well as their beliefs) impacted how they assessed the severity of COVID-19. We present vignettes of citizens’ schemes that inhibited interpreting representations of COVID-19 in ways compatible with the displayed quantitative data, schemes that aided them in assessing the severity of COVID-19, and beliefs about the reliability of scientific data that overrode their mathematical conclusions. 相似文献
73.
This paper presents a method for establishing relations between entropy-based measures applied to graphs. A special class of relations called implicit information inequalities or implicit entropy bounds is developed. A number of entropy-based measures of the structural information content of a graph have been developed over the past several decades, but little attention has been paid to relations among these measures. The research reported here aims to remedy this deficiency. 相似文献
74.
V. Metaftsis 《代数通讯》2013,41(11):3879-3886
We show that if the fundamental group of a finite graph of groups with finitely generated Abelian vertex groups is subgroup separable, then it is linear. 相似文献
75.
A new optimisation problem for design of multi-position machines and automatic transfer lines is considered. To reduce the number of pieces of equipment, machining operations are grouped into blocks. The operations of the same block are performed simultaneously by one piece of equipment (multi-spindle head). At the studied design stage, constraints related to the design of blocks and workstations, as well as precedence constraints for operations are known. The problem consists in an optimal grouping of the operations into blocks minimizing the total number of blocks and workstations while reaching a given cycle time (productivity). A constrained shortest path algorithm is developed and tested. 相似文献
76.
A.M. Blokh 《Journal of Difference Equations and Applications》2013,19(3-4):343-357
We characterize sets of periods of cycles which arbitrary continuous graph maps may have. In this investigation, we need the spectral decomposition for graph maps [Blokh, A.M. "On dynamical systems on one-dimensional branched manifolds", Theory Funct. Funct. Anal. Appl. Kharkov 46 (1986) pp. 8-18 (Russian); 47 (1986) pp. 67-77; 48 (1987) pp. 32-46] briefly described in "The Spectral Decomposition" Section. 相似文献
77.
Florent Hivert Jean-Christophe Novelli Jean-Yves Thibon 《Journal of Algebraic Combinatorics》2008,28(1):65-95
We propose several constructions of commutative or cocommutative Hopf algebras based on various combinatorial structures and
investigate the relations between them. A commutative Hopf algebra of permutations is obtained by a general construction based
on graphs, and its noncommutative dual is realized in three different ways, in particular, as the Grossman–Larson algebra
of heap-ordered trees. Extensions to endofunctions, parking functions, set compositions, set partitions, planar binary trees,
and rooted forests are discussed. Finally, we introduce one-parameter families interpolating between different structures
constructed on the same combinatorial objects. 相似文献
78.
Peter Beelen 《Journal of Number Theory》2004,108(2):217-240
In this paper we state and explore a connection between graph theory and the theory of recursively defined towers. This leads, among other things, to a generalization of Lenstra's identity (Finite Fields Appl. 8 (2001) 166) and the solution of an open problem concerning the Deuring polynomial posed in (J. Reine Angew. Math. 557 (2003) 53). Further we investigate the effect extension of the constant field has on the limit of certain towers. 相似文献
79.
We introduce the lexicographic balanced optimization problem (LBaOP) and show that it can be solved efficiently if an associated lexicographic bottleneck problem can be solved efficiently. For special cases of cuts in a graph and base system of a matroid, improved algorithms are proposed. A generalization of LBaOP is also discussed. 相似文献
80.