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101.
Antoine Musitelli 《Mathematical Programming》2010,124(1-2):349-381
Binet matrices generalize network matrices and play an important role in combinatorial optimization. A first polynomial-time algorithm for recognizing binet matrices appeared in the author’s doctoral thesis. In this paper, we present some key ideas and results involved in the design of this algorithm. We show how we can find a Camion basis of the input matrix, whenever this one is binet, and then reduce the recognition problem to that of special binet matrices called bicyclic and cyclic. 相似文献
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Antoine Bonnefont Franoise Argoul Martin Z. Bazant 《Journal of Electroanalytical Chemistry》2001,500(1-2)
We investigate the subtle effects of the diffuse charged layer on interfacial kinetics by solving the governing equations for ion transport (Nernst–Planck) with realistic boundary conditions representing reaction kinetics (Butler–Volmer) and compact-layer capacitance (Stern) in the asymptotic limit =λD/L→0, where λD is the Debye screening length and L is the distance between the working and counter electrodes. Using the methods of singular perturbation theory, we derive the leading-order steady-state response to a nonzero applied current in the case of the oxidation of a neutral species into cations, without any supporting electrolyte. In certain parameter regimes, the theory predicts a reaction-limited current smaller than the classical diffusion-limited current; this over potential effect is not due to ohmic drop effects in the bulk of the cell but rather to antagonist processes involved in the surface charge transfer and diffuse layer charging respectively. We demonstrate that the charging of diffuse charge, since it is intimately coupled to the surface reaction and cannot be considered independently, plays a fundamental role in nonequilibrium surface reactions when the transport of one of the reacting species is coupled to the total interfacial response of the compact and diffuse layers. 相似文献
105.
The classical game of Peg Solitaire has uncertain origins, but was certainly popular by the time of Louis XIV, and was described
by Leibniz in 1710. The modern mathematical study of the game dates to the 1960s, when the solitaire cone was first described
by Boardman and Conway. Valid inequalities over this cone, known as pagoda functions, were used to show the infeasibility
of various peg games. In this paper we study the extremal structure of solitaire cones for a variety of boards, and relate
their structure to the well studied metric cone. In particular we give:?1. an equivalence between the multicommodity flow
problem with associated dual metric cone and a generalized peg game with associated solitaire cone;?2. a related NP-completeness
result;?3. a method of generating large classes of facets;?4. a complete characterization of 0-1 facets;?5. exponential upper
and lower bounds (in the dimension) on the number of facets;?6. results on the number of facets, incidence and adjacency relationships
and diameter for small rectangular, toric and triangular boards;?7. a complete characterization of the adjacency of extreme
rays, diameter, number of 2-faces and edge connectivity for rectangular toric boards.
Received: July 1996 / Accepted: February 2000?Published online February 22, 2001 相似文献
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J. H. Coste C. Z. Rosecrans E. Selivounoff 《Analytical and bioanalytical chemistry》1931,83(9-10):379-381
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