Showing papers in "Operations Research Letters in 1999"

TL;DR: It is shown that the RC of an LP with ellipsoidal uncertainty set is computationally tractable, since it leads to a conic quadratic program, which can be solved in polynomial time.

TL;DR: It is shown that, in expectation, z^*"n is a lower bound on z* and that this bound monotonically improves as n increases, and confidence intervals are constructed on the optimality gap for any candidate solution x@^ to SP.

TL;DR: An algorithm for solving stochastic integer programming problems with recourse, based on a dual decomposition scheme and Lagrangian relaxation, which can be applied to multi-stage problems with mixed-integer variables in each time stage.

TL;DR: For the first time, animal data have been collected that indicate the possibility of nearly interference-free use of both stimulation types simultaneously simultaneously, and the first clinical patient experience is gathered, which confirms the encouraging results.

TL;DR: The significance of a diagnosis of large vestibular aqueduct syndrome, in the presence of serviceable hearing, is that it identifies patients who should refrain from activities that increase intracranial pressure to prevent hearing loss.

TL;DR: Stochastic mathematical programs with equilibrium constraints (SMPEC), which generalize MPEC models by explicitly incorporating possible uncertainties in the problem data to obtain robust solutions to hierarchical problems, are introduced.

TL;DR: This work is based on a precise norm-dependent explicit closed form for the projection of a point on a plane that is used to formulate the separating-plane problem as a minimization of a convex function on a unit sphere in a norm dual to that of the arbitrary norm used.

TL;DR: This paper proposes a new approach for solving the general capacitated (or uncapacitated) FCNFP by adapting an economic viewpoint of the fixed cost by presenting a new concept of the dynamic slope scaling procedure.

TL;DR: This paper proposes practical modeling and analysis methods to facilitate dynamic staffing in a telephone call center with the objective of immediately answering all calls using infinite-server queueing models.

TL;DR: The proposed procedure may be viewed as a specialization of the well-known BENDERS partitioning procedure, leading to iteratively solving an integer 0-1 linear programming relaxed subproblem which is progressively augmented through constraint generation.

TL;DR: In this article, a Minimax Regret formulation suitable for large-scale linear programming models was proposed for Greenhouse Gas abatement in the Province of Quebec, where the minimax regret strategy depends only on the extremal scenarios and not on intermediate ones, thus making the approach computationally efficient.

TL;DR: This paper considers the case where demand is discrete and provides examples to show that ordering products from the more expensive (and more reliable) supplier alone is optimal, and provides sufficient conditions under which it is optimal to order a larger share from theMore expensive supplier whenDemand is discrete.

TL;DR: It can be concluded that NO together with O–2, which form more reactive peroxynitrite, play an important role in GM ototoxicity in the guinea pig.

TL;DR: It is proved that the relevant cost is convex with the number of replenishments and the search for the optimal replenishment number is reduced to finding a local minimum.

TL;DR: It is concluded that the finding of a vibration-induced nystagmus reflects a side difference of peripheral vestibular excitability.

TL;DR: A new linear programming relaxation for the problem of minimizing the sum of weighted completion times of precedence-constrained jobs is presented, which provides a new 2-approximation algorithm in the complexity of a minimum cut on a graph.

TL;DR: This work studies the problem of minimizing, in the preemptive case, the number of late jobs on a single machine (1|pmtn,r"j|@?U"j) and proposes a new dynamic programming algorithm whose complexities are respectively O(n^4) and O( n^2).

TL;DR: This paper describes a class of rounding methods that exploits the structure and geometry of the underlying problem to round fractional solution to 0-1 solution and shows that this technique can be used to establish the integrality of several classical polyhedra.

TL;DR: A novel Branch and Bound algorithm is described based on successive solutions of parametric linear programs where n right-hand side parameters are allowed to vary independently.

TL;DR: A three-dimensional mechanical model of the cochlea including the fluid-structure couplings is developed and evaluated numerically by finite elements and it is now easy to calculate the mechanical input impedance of the Cochlear partition.

TL;DR: Hyalinizing clear cell carcinoma is a rare, recently described tumor of salivary gland origin and a favorable prognosis after wide local excision has been evidenced.

TL;DR: Otomicroscopically and Histologically, sclerotic lesions were present in the pars tensa and pars flaccida 9 and 12 h, respectively, after myringotomy, which indicates that myringosclerosis develops promptly after my ringotomy and its establishment is related to an inflammatory reaction.

TL;DR: This paper presents efficient lower and upper bound procedures and a branch and bound algorithm which is able to find the exact solution of large instances, employing short computing times.

TL;DR: The results of this investigation reveal a strong correlation between the clinical symptomatology and the in vitro parameters of eicosanoid levels in isolated blood cells, indicating the need to induce aspirin tolerance to reduce the risk of recurrent rhinosinusitis.

TL;DR: This work considers the ordered cluster traveling salesman problem (OCTSP), a problem in which a vehicle starting and ending at a given depot must visit a set of n points.

TL;DR: It is shown that, as long as the number of objects is given in advance, the selector can pick a maximal one with probability at least 18, without prior knowledge of the partial order.

TL;DR: This work proposes a general rule which leads, given the considered problem, to a vectorial version of the solution procedure for the underlying sum optimization (minsum) problem.

TL;DR: The two main ideas implemented are a primal-dual subproblem simplex method and a compact matrix storage scheme to speed up linear programming solution times.

TL;DR: In this paper, a polynomial-time approximation algorithm with worst case ratio 2 for the case that the number s of stages is part of the input is presented, based on Racsmany's concept of dense schedules.

TL;DR: 3D imaging of temporal bone specimens with intact regions of interest and spatial resolution currently in the 10-μm range, but providing capabilities for future enhancements down to the submicron level is presented.