A Recombination-Based Tabu Search Algorithm for the Winner Determination Problem

Abstract. We propose a dedicated tabu search algorithm (TSX_WDP) for the winner determination problem (WDP) in combinatorial auctions. TSX_WDP integrates two complementary neighborhoods designed re-spectively for intensification and diversification. To escape deep local optima, TSX_WDP employs a backbone-based recombination opera-tor to generate new starting points for tabu search and to displace the search into unexplored promising regions. The recombination operator operates on elite solutions previously found which are recorded in an global archive. The performance of our algorithm is assessed on a set of 500 well-known WDP benchmark instances. Comparisons with five state of the art algorithms demonstrate the effectiveness of our approach

Towards a European ITS for freight transport and logistics: results of current EU funded research and prospects for the future

Objective The purpose of this paper is to review the developments of the last 15 years in the field of Freight Transport research and innovation, primarily (but not exclusively) in Europe focusing on the “Intelligent Transport Systems” aspects. Document type: Articl

An auction mechanism for multilateral procurement based on Dantzig-Wolfe Decomposition

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Traffic analysis for GSM networks

When GSM was introduced in the early 90's, it was considered an over specified system. Nowadays, it is obvious that the whole range of services is widely in use. In addition, performance is degrading due to the rapidly increasing number of mobile subscribers, numbering over 2.9 billion subscribers around the world. The performance of cellular networks is the most important issue concerning their operators. The main goal is to keep subscribers satisfied with the delivered quality of service (QoS). In order to achieve the best performance, service providers have to monitor and optimize their network continuously. A Network Management System (NMS) with an online database is responsible for the collection of data on live networks. For greater effectiveness, operators install systems that do a lot more than collect and store raw data. These systems are easier to use and take advantage of all the data provided by the NMS. In this paper, we summarize measurements that were carried out on an operative GSM-1900 network to evaluate the performance of the GSM's Air-Interface (Um), during eight months. In this paper we have established statistically the following facts: (i) The peak hour in North America is between 4:00 and 5:00 PM. (ii) During week days the duration of calls increases from Monday through Friday. (iii) Weekend traffic is different from week-days traffic. Using a regression analysis we forecast traffic over time. The presented KPIs along with the derived statistical facts are crucial for operators who are concerned with maintaining a reliable and stable network, while maintaining an acceptable QoS

A study of auction mechanisms for multilateral procurement based on subgradient and bundle methods

The use of iterative auctions is very common in procurement processes, where the market-maker often does not have access to complete and truthful information about the bidders' private valuations of the resources on sale. The literature on the design of iterative mechanisms for combinatorial auctions has addressed only the most basic cases and has been dominated by primal-dual approaches. In this paper, we consider a general production/consumption exchange of interdependent goods, for which we investigate iterative auction mechanisms based on mathematical programming dual decomposition methods. We focus on Lagrangian relaxation and the solution of the Lagrangian dual through subgradient algorithms and the bundle method. A case study of a simulated wood chip market is used to evaluate numerically the efficiency of the mechanisms