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SENSORS ON SPEAKING TERMS SCHEDULEBASED MEDIUM ACCESS CONTROL PROTOCOLS FOR WIRELESS SENSOR NETWORKS
"... Sensors on speaking terms Schedulebased medium access control protocols for wireless sensor networks Lodewijk F.W. van Hoesel ..."
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Sensors on speaking terms Schedulebased medium access control protocols for wireless sensor networks Lodewijk F.W. van Hoesel
Scheduling to Minimize Average Completion Time: Offline and Online Algorithms
, 1996
"... Timeindexed linear programming formulations have recently received a great deal of attention for their practical effectiveness in solving a number of singlemachine scheduling problems. We show that these formulations are also an important tool in the design of approximation algorithms with good wo ..."
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Cited by 228 (24 self)
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Timeindexed linear programming formulations have recently received a great deal of attention for their practical effectiveness in solving a number of singlemachine scheduling problems. We show that these formulations are also an important tool in the design of approximation algorithms with good worstcase performance guarantees. We give simple new rounding techniques to convert an optimal fractional solution into a feasible schedule for which we can prove a constantfactor performance guarantee, thereby giving the first theoretical evidence of the strength of these relaxations. Specifically, we consider the problem of minimizing the total weighted job completion time on a single machine subject to precedence constraints, and give a polynomialtime (4 + ffl)approximation algorithm, for any ffl ? 0; the best previously known guarantee for this problem was superlogarithmic. With somewhat larger constants, we also show how to extend this result to the case with release date constraints, ...
Polynomial cases of the tarification problem Stan van Hoesel ∗ Anton F. van der Kraaij † Carlo Mannino
, 2003
"... We consider the problem of determining a set of optimal tariffs for an agent in a network, who owns a subset of the arcs of the network, and who wishes to maximize his revenues on this subset from a set of clients that make use of the network. The general variant of this problem is NPhard, already ..."
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We consider the problem of determining a set of optimal tariffs for an agent in a network, who owns a subset of the arcs of the network, and who wishes to maximize his revenues on this subset from a set of clients that make use of the network. The general variant of this problem is NPhard, already with a single client. This paper introduces several new polynomially solvable special cases. An important case is the following. For multiple clients, if the number of tariff arcs is bounded from above, we can solve the problem by a polynomial number of linear programs (each of which is of polynomial size). Furthermore, we show that the parametric tarification problem and the single arc fixed charge tarification problem can be solved in polynomial time. Subject Classification: Networks, Combinatorial Optimization, Bilevel Programs. 1
OUTWARD INVESTMENT FROM THE NETHERLANDS: INTRODUCTION AND OVERVIEW 1
"... Forthcoming in, [R. van Hoesel and R.Narula (eds)] ‘Multinationals from the ..."
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Forthcoming in, [R. van Hoesel and R.Narula (eds)] ‘Multinationals from the
R.L.M.J. van de Leensel C.P.M. van Hoesel J.J. van de Klundert Lifting valid inequalities for the precedence constrained knapsack problem
, 1997
"... Abstract. This paper considers the precedence constrained knapsack problem. More specifically, we are interested in classes of valid inequalities which are facetdefining for the precedence constrained knapsack polytope. We study the complexity of obtaining these facets using the standard sequential ..."
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Abstract. This paper considers the precedence constrained knapsack problem. More specifically, we are interested in classes of valid inequalities which are facetdefining for the precedence constrained knapsack polytope. We study the complexity of obtaining these facets using the standard sequential lifting procedure. Applying this procedure requires solving a combinatorial problem. For valid inequalities arising fromminimal induced covers, we identify a class of lifting coefficients for which this problem can be solved in polynomial time, by using a supermodular function, and for which the values of the lifting coefficients have a combinatorial interpretation. For the remaining lifting coefficients it is shown that this optimization problem is strongly NPhard. The same lifting procedure can be applied to (1,k)configurations, although in this case, the same combinatorial interpretation no longer applies. We also consider Kcovers, to which the same procedure need not apply in general. We show that facets of the polytope can still be generated using a similar lifting technique. For tree knapsack problems, we observe that all lifting coefficients can be obtained in polynomial time. Computational experiments indicate that these facets significantly strengthen the LPrelaxation. 1.
unknown title
, 1994
"... ) algorithm for the economic lotsizing problem with constant capacities C.P.M. van Hoesel ..."
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) algorithm for the economic lotsizing problem with constant capacities C.P.M. van Hoesel
Models and Solution Techniques for Frequency Assignment Problems
, 2001
"... Wireless communication is used in many different situations such as mobile telephony, radio and TV broadcasting, satellite communication, and military operations. In each of these situations a frequency assignment problem arises with application specific characteristics. Researchers have developed d ..."
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Cited by 106 (9 self)
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Wireless communication is used in many different situations such as mobile telephony, radio and TV broadcasting, satellite communication, and military operations. In each of these situations a frequency assignment problem arises with application specific characteristics. Researchers have developed different modeling ideas for each of the features of the problem, such as the handling of interference among radio signals, the availability of frequencies, and the optimization criterion. This survey
Local branching
 MATHEMATICAL PROGRAMMING
, 2002
"... The availability of effective exact or heuristic solution methods for general MixedInteger Programs (MIPs) is of paramount importance for practical applications. In the present paper we investigate the use of a generic MIP solver as a blackbox “tactical ” tool to explore effectively suitable solu ..."
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Cited by 91 (8 self)
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The availability of effective exact or heuristic solution methods for general MixedInteger Programs (MIPs) is of paramount importance for practical applications. In the present paper we investigate the use of a generic MIP solver as a blackbox “tactical ” tool to explore effectively suitable solution subspaces defined and controlled at a “strategic” level by a simple external branching framework. The procedure is in the spirit of wellknown local search metaheuristics, but the neighborhoods are obtained through the introduction in the MIP model of completely general linear inequalities called local branching cuts. The new solution strategy is exact in nature, though it is designed to improve the heuristic behavior of the MIP solver at hand. It alternates highlevel strategic branchings to define the solution neighborhoods, and lowlevel tactical branchings to explore them. The result is a completely general scheme aimed at favoring early updatings of the incumbent solution, hence producing highquality solutions at early stages of the computation. The method is analyzed computationally on a large class of very difficult MIP problems by using the stateoftheart commercial software ILOGCplex 7.0 as the blackbox tactical MIP solver. For these instances, most of which cannot be solved to proven optimality in a reasonable time, the new method exhibits consistently an improved heuristic performance: in 23 out of 29 cases, the MIP solver produced significantly better incumbent solutions when driven by the local branching paradigm.
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