On the calculation of steady-state loss probabilities in the queue.
On the coefficients of variation of uptime and downtime in manufacturing equipment.
On the complexity of the subgraph problem
On the computational complexity of centers locating in a graph
It is shown that the problem of finding a minimum -basis, the -center problem, and the -median problem are -complete even in the case of such communication networks as planar graphs with maximum degree 3. Moreover, a near optimal -center problem is also -complete.
On the connection between the theory of signal flow graphs and the theory of directed graphs
On the convergence of truncated processes of multiserver retrial queues.
On the ergodic distribution of oscillating queueing systems.
On the generalization of the STER distribution applied to generalized hypergeometric parents
On the hardness of approximating the UET-UCT scheduling problem with hierarchical communications
We consider the unit execution time unit communication time (UET-UCT) scheduling model with hierarchical communications [1], and we study the impact of the hierarchical communications hypothesis on the hardness of approximation. We prove that there is no polynomial time approximation algorithm with performance guarantee smaller than (unless ). This result is an extension of the result of Hoogeveen et al. [6] who proved that there is no polynomial time -approximation algorithm with for the...
On the hardness of approximating the UET-UCT scheduling problem with hierarchical communications
We consider the unit execution time unit communication time (UET-UCT) scheduling model with hierarchical communica tions [CITE], and we study the impact of the hierarchical communications hypothesis on the hardness of approximation. We prove that there is no polynomial time approximation algorithm with performance guarantee smaller than 5/4 (unless P = NP). This result is an extension of the result of Hoogeveen et al. [CITE] who proved that there is no polynomial time ρ-approximation algorithm...
On the Implementation of Stochastic Quasigradient Methods to some Facility Location Problems
On the level crossing of multi-dimensional delayed renewal processes.
On the mathematical aspects of an urban retail model
On the maximum probability criteria concerning the sequencial decision-making problem.
On the M/G/1 retrial queue subjected to breakdowns
Retrial queueing systems are characterized by the requirement that customers finding the service area busy must join the retrial group and reapply for service at random intervals. This paper deals with the M/G/1 retrial queue subjected to breakdowns. We use its stochastic decomposition property to approximate the model performance in the case of general retrial times.
On the M/G/1 retrial queue subjected to breakdowns
Retrial queueing systems are characterized by the requirement that customers finding the service area busy must join the retrial group and reapply for service at random intervals. This paper deals with the M/G/1 retrial queue subjected to breakdowns. We use its stochastic decomposition property to approximate the model performance in the case of general retrial times.
On the minimum cost multiple-source unsplittable flow problem
The minimum cost multiple-source unsplittable flow problem is studied in this paper. A simple necessary condition to get a solution is proposed. It deals with capacities and demands and can be seen as a generalization of the well-known semi-metric condition for continuous multicommdity flows. A cutting plane algorithm is derived using a superadditive approach. The inequalities considered here are valid for single knapsack constraints. They are based on nondecreasing superadditive functions and...
On the minimum dummy-arc problem
On the modelling and management of traffic
Several realistic situations in vehicular traffic that give rise to queues can be modeled through conservation laws with boundary and unilateral constraints on the flux. This paper provides a rigorous analytical framework for these descriptions, comprising stability with respect to the initial data, to the boundary inflow and to the constraint. We present a framework to rigorously state optimal management problems and prove the existence of the corresponding optimal controls. Specific cases are...
On the modelling and management of traffic
Several realistic situations in vehicular traffic that give rise to queues can be modeled through conservation laws with boundary and unilateral constraints on the flux. This paper provides a rigorous analytical framework for these descriptions, comprising stability with respect to the initial data, to the boundary inflow and to the constraint. We present a framework to rigorously state optimal management problems and prove the existence of the corresponding optimal controls. Specific cases...