Search results for "Crete"

Formulations for an inventory routing problem

2014

In this paper, we present and compare formulations for the inventory routing problem (IRP) where the demand of customers has to be served, over a discrete time horizon, by capacitated vehicles starting and ending their routes at a depot. The objective of the IRP is the minimization of the sum of inventory and transportation costs. The formulations include known and new mathematical programming formulations. Valid inequalities are also presented. The formulations are tested on a large set of benchmark instances. One of the most significant conclusions is that the formulations that use vehicle-indexed variables are superior to the more compact, aggregate formulations.

On minimal ∗-identities of matrices∗

1995

Let Mn (F) be the algebra of n×n matrices (n≥2) over a field F of characteristic different from 2 and let ∗ be an involution in Mn (F) In case ∗ is the transpose involution, we construct a multilinear ∗ polynomial identify of Mn (F) of degree 2n−1, P 2n−1(k 1, s 2, … s 2n−1) in one skew variable and the remaining symmetric variables of minimal degree among all ∗-polynomial identities of this type. We also prove that any other multilinear ∗-polynomial identity of Mn (F) of this type of degree 2n−1 is a scalar multiple of P2n−1 . In case ∗ is the symplectic involution in Mn (F), we construct a ∗-polynomial identity of Mn (F) of degree 2n−1 in skew variables T2n−1 (k 1,…,k 2n−1) and we prove t…

ALGEBRAS WITH INVOLUTION WHOSE EXPONENT OF THE *-CODIMENSIONS IS EQUAL TO TWO

2002

ABSTRACT Let be a finite dimensional algebra with involution over a field of characteristic zero. In studying the sequence of -codimensions of , the notion of the -PI-exponent of has recently been introduced. We characterize algebras with involution having -PI-exponent greater than two and those having -PI-exponent equal to two.

The Hermitian part of a Rickart involution ring, I

2014

Rickart *-rings may be considered as a certain abstraction of the rings B(H) of bounded linear operators of a Hilbert space H. In 2006, S. Gudder introduced and studied a certain ordering (called the logical order) of self-adjoint Hilbert space operators; the set S(H) of these operators, which is a partial ring, may be called the Hermitian part of B(H). The new order has been further investigated also by other authors. In this first part of the paper, an abstract analogue of the logical order is studied on certain partial rings that approximate the Hermitian part of general *-rings; the special case of Rickart *-rings is postponed to the next part.

Algorithms for rational discrete least squares approximation

1975

In this paper an algorithm for the computation of a locally optimal polefree solution to the discrete rational least squares problem under a mild regularity condition is presented. It is based on an adaptation of projection methods [8], [12], [13], [14], [18], [19] to the modified Gaus-Newton method [4], [10]. A special device makes possible the direct handling of the infinitely many linear constraints present in this problem.

Reclutamiento y reclutas en la ciudad de Valencia (1717-1762)

2019

This research aims to analyze recruitment by quintas, Spanish word for recruitment levies by lot, in the city of Valencia and the townships included in its jurisdictional area. The analyzed period began in 1717 with the first levie decreted by king Philip V once the War of Spanish Succession was over. Applied this levie in the kingdom of Valencia, this was the first application of levies by lot. The closing year for the reported period up to 1762, whith the last levy made by king Charles III before the establishment of the annual periodicity for the recruitment process. Procedures with which human contingents claimed to the city of Valencia between the mentioned dates were organized and dis…

Khovanov–Rozansky homology for embedded graphs

2011

Vertical Representation of C∞-words

2015

International audience; We present a new framework for dealing with C∞-words, based on their left and right frontiers. Thisallows us to give a compact representation of them, and to describe the set of C∞-words throughan infinite directed acyclic graph G. This graph is defined by a map acting on the frontiers ofC∞-words. We show that this map can be defined recursively and with no explicit reference toC∞-words. We then show that some important conjectures on C∞-words follow from analogousstatements on the structure of the graph G.

Some Remarks on Differentiable Sequences and Recursivity

2010

International audience; We investigate the recursive structure of differentiable sequences over the alphabet {1, 2}. We derive a recursive formula for the (n + 1)-th symbol of a differentiable sequence, which yields to a new recursive formula for the Kolakoski sequence. Finally, we show that the sequence of absolute differences of consecutive symbols of a differentiable sequence u is a morphic image of the run-length encoding of u.

Representation of Autonomous Automata

2001

An autonomous automaton is a finite automaton with output in which the input alphabet has cardinality one when special reduced. We define the transition from automata to semigroups via a representation successful if given two incomparable automata (neither simulate the other), the semigroups representing the automata are distinct. We show that representation by the transition semigroup is not successful. We then consider a representation of automata by semigroups of partial transformations. We show that in general transition from automata to semigroups by this representation is not successful either. In fact, the only successful transition presented is the transiton to this semigroup of par…