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81.
Prof. Josep M. Ribó Dr. David Hochberg 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(52):13098-13106
The way chemical transformations are described by models based on microscopic reversibility does not take into account the irreversibility of natural processes, and therefore, in complex chemical networks working in open systems, misunderstandings may arise about the origin and causes of the stability of non-equilibrium stationary states, and general constraints on evolution in systems that are far from equilibrium. In order to be correctly simulated and understood, the chemical behavior of complex systems requires time-dependent models, otherwise the irreversibility of natural phenomena is overlooked. Micro reversible models based on the reaction-coordinate model are time invariant and are therefore unable to explain the evolution of open dissipative systems. The important points necessary for improving the modeling and simulations of complex chemical systems are: a) understanding the physical potential related to the entropy production rate, which is in general an inexact differential of a state function, and b) the interpretation and application of the so-called general evolution criterion (GEC), which is the general thermodynamic constraint for the evolution of dissipative chemical systems. 相似文献
82.
Josep Àlvarez Montaner 《代数通讯》2013,41(9):3695-3704
We prove that sequentially Cohen–Macaulay rings in positive characteristic, as well as sequentially Cohen–Macaulay Stanley–Reisner rings in any characteristic, have trivial Lyubeznik table. Some other configurations of Lyubeznik tables are also provided depending on the deficiency modules of the ring. 相似文献
83.
Josep Maria Izquierdo 《TOP》2006,14(2):375-398
The paper introduces a refinement of the notion of population monotonic allocation scheme, called regular population monotonic
allocation scheme (regularpmas). This refinement is based on economic situations in which players may have to select new partners from a set of potential
players and in which there exist certain capacity constraints. A sufficient condition for the existence of a regularpmas is given. For the class of games with regularpmas, we prove that the core coincides with the Davis and Maschler and the Mas-Colell bargaining sets. 相似文献
84.
We present a new generic problem solving approach for over-constrained problems based on Max-SAT. We first define a Boolean
clausal form formalism, called soft CNF formulas, that deals with blocks of clauses instead of individual clauses, and that allows one to declare each block either as hard (i.e., must be satisfied by any solution) or soft (i.e., can be violated by some solution). We then present two Max-SAT solvers that find a truth assignment that satisfies
all the hard blocks of clauses and the maximum number of soft blocks of clauses. Our solvers are branch and bound algorithms
equipped with original lazy data structures, powerful inference techniques, good quality lower bounds, and original variable
selection heuristics. Finally, we report an experimental investigation on a representative sample of instances (random 2-SAT,
Max-CSP, graph coloring, pigeon hole and quasigroup completion) which provides experimental evidence that our approach is
very competitive compared with the state-of-the-art approaches developed in the CSP and SAT communities.
Research partially supported by projects TIN2004-07933-C03-03 and TIC2003-00950 funded by the Ministerio de Educación y Ciencia. The second author is supported by a grant Ramón y Cajal. 相似文献
85.
Josep M. Brunat 《Discrete Mathematics》2006,306(4):401-412
Let Φ(x,y) be a bivariate polynomial with complex coefficients. The zeroes of Φ(x,y) are given a combinatorial structure by considering them as arcs of a directed graph G(Φ). This paper studies some relationship between the polynomial Φ(x,y) and the structure of G(Φ). 相似文献
86.
87.
An axiomatic characterization of ‘a Banzhaf score’ notion is provided for a class of games called (j,k) simple games with a numeric measure associated to the output set, i.e., games with n players, j ordered qualitative alternatives in the input level and k possible ordered quantitative alternatives in the output. Three Banzhaf measures are also introduced which can be used to
determine a player's ‘a priori’ value in such a game. We illustrate by means of several real world examples how to compute
these measures.
Research partially supported by Grant BFM 2003-01314 of the Science and Technology Spanish Ministry and the European Regional
Development Fund. 相似文献
88.
A basic problem in the theory of simple games and other fields is to study whether a simple game (Boolean function) is weighted
(linearly separable). A second related problem consists in studying whether a weighted game has a minimum integer realization.
In this paper we simultaneously analyze both problems by using linear programming.
For less than 9 voters, we find that there are 154 weighted games without minimum integer realization, but all of them have minimum normalized realization. Isbell in 1958 was the first to find a weighted game without a minimum normalized
realization, he needed to consider 12 voters to construct a game with such a property. The main result of this work proves
the existence of weighted games with this property with less than 12 voters.
This research was partially supported by Grant MTM 2006-06064 of “Ministerio de Ciencia y Tecnología y el Fondo Europeo de
Desarrollo Regional” and SGRC 2005-00651 of “Generalitat de Catalunya”, and by the Spanish “Ministerio de Ciencia y Tecnología”
programmes ALINEX (TIN2005-05446 and TIN2006-11345). 相似文献
89.
We consider a bounded version of the restrictive and the restrictive list H-coloring problem in which the number of pre-images of certain vertices of H is taken as parameter. We consider the decision and the counting versions, as well as, further variations of those problems. We provide complexity results identifying the cases when the problems are NP-complete or #P-complete or polynomial time solvable. We conclude stating some open problems. 相似文献
90.
Given a Jordan matrix J, we obtain an explicit formula for the determinant of any matrix T that commutes with it. 相似文献