Les tables de réservation numériques : un outil pour la résolution de certains problèmes d'ordonnancement cycliques
Lexicographic α-robustness: an application to the 1-median problem
In the last decade, several robustness approaches have been developed to deal with uncertainty. In decision problems, and particularly in location problems, the most used robustness approach rely either on maximal cost or on maximal regret criteria. However, it is well known that these criteria are too conservative. In this paper, we present a new robustness approach, called lexicographic α-robustness, which compensates for the drawbacks of criteria based on the worst case. We apply this approach...
Limit Theorems for Two-unit Standby Redundant Sistems with Rapid Repair and Rapid Preventive Maintenance
Limited space double channel Markovian queue with heterogeneus servers.
For a double channel Markovian queue with finite waiting space and unequal service rates at the two counters, the difference equations satisfied by the Laplace transforms of the state probabilities at finite time are solved and the state probabilities have been obtained. The closed form of the state probabilities can be used to obtain the important parameters of the system.
Limites d'emploi imposées par la contrainte de sélectivité aux systèmes de transport guidé en site propre
L'importance des réseaux en économie
Linear approach for synchronous state stability in fully connected PLL networks.
Little's formula for work-conserving normal G/G/1 queues in series
Localización minimax bajo posiciones aleatorias de los destinos.
En este trabajo estudiamos el problema de localización minimax cuando no se conocen exactamente las coordenadas de los destinos, pero vienen especificadas por variables aleatorias con distribución conocida. Hemos analizado este problema bajo el criterio del valor esperado y el criterio de probabilidad máxima, por medio de la dominancia estocástica. Probamos, a través del concepto de valor esperado de información perfecta, que se puede obtener una reducción considerable de la distancia máxima cuando...
Localización sobre redes estocásticas con criterio minisum.
Se considera el problema de localización de centros de servicio sobre redes estocásticas, donde los puntos de demanda son cada uno de los puntos de los arcos, así como los nodos de la red y el tiempo de duración de los trayectos, sobre los arcos de la red, son variables aleatorias discretas con distribuciones de probabilidad conocidas. Bajo un conjunto particular de supuestos, se encuentra que siempre existe un conjunto de m puntos de la red que son puntos medios de los arcos, o nodos de la red,...
Localizzazione di impianti e instradamento di materiali nocivi: il caso discreto
Location of polygon vertices on circles and its application in transport studies
The paper deals with the problem how to locate a set of polygon vertices on given circles fulfilling some criteria of "regularity" of individual and composed polygons. Specifying the conditions we can obtain a lot of particular versions of this general problem. Some of them are already solved, the others are not. Applications of this theory can be found in scheduling of periodically repeating processes, e.g. in coordination of several urban lines on a common leg, in optimization of the rhythm of...
Location patterns and distances in Tinbergen-Bos systems
Locational equilibrium of two facilities on a tree
Long-run availability of a priority system: a numerical approach.
Long-term planning versus short-term planning in the asymptotical location problem
Given the probability measure over the given region , we consider the optimal location of a set composed by points in in order to minimize the average distance (the classical optimal facility location problem). The paper compares two strategies to find optimal configurations: the long-term one which consists in placing all points at once in an optimal position, and the short-term one which consists in placing the points one by one adding at each step at most one point and preserving...
Long-term planning versus short-term planning in the asymptotical location problem
Given the probability measure ν over the given region , we consider the optimal location of a set Σ composed by n points in Ω in order to minimize the average distance (the classical optimal facility location problem). The paper compares two strategies to find optimal configurations: the long-term one which consists in placing all n points at once in an optimal position, and the short-term one which consists in placing the points one by one adding at each step at most one point and preserving...
Lower bounds for the scheduling problem with uncertain demands
This paper proposes various lower bounds to the makespan of the flexible job shop scheduling problem (FJSP). The FJSP is known in the literature as one of the most difficult combinatorial optimisation problems (NP-hard). We will use genetic algorithms for the optimisation of this type of problems. The list of the demands is divided in two sets: the actual demand, which is considered as certain (a list of jobs with known characteristics), and the predicted demand, which is a list of uncertain jobs....
Lower bounds to the graph partitioning problem through generalized linear programming and network flows