4 présentations

• 
  15h30 - 15h55

  Multi-attribute bid construction for TL transportation services procurement

  • abir bahri, prés., Université Laval
  • Rekik Monia, Université Laval
  • Hajji Adnene, Université Laval

  We consider a transportation services procurement auction in which the carriers -invited to participate- compete by submitting combinatorial bids on the shipper’s requests. Each shipper’s request is characterized by its pick-up and delivery locations, the volume to be shipped, the time widow within which the delivery must be done and a target delivery time. Each carrier is assumed to submit a single combinatorial bid including the set of shipments the carrier is interested in, the price asked for servings all these shipments as well as the delivery time promised for each TL shipment. We propose different mathematical models to formulate the problem in different contexts related to the carrier’s existing commitments. Preliminary results will be presented.

• 
  15h55 - 16h20

  Auction-Based Procurement of Transportation Services: A review and new trends

  • Mehdi Changizi, prés., Département d'opérations et systèmes de décision, Université Laval, Pavillon Palasis-Prince, Québec, Canada
  • Monia Rekik, Département d'opérations et systèmes de décision, Université Laval, Pavillon Palasis-Prince, Québec, Canada
  • Mikael Rönnqvist, Université Laval

  Procuring transportation services efficiently is crucial for organizations facing rising freight costs, fluctuating demand, and the need for flexible logistics. Auction mechanisms have been used for decades for the procurement of transportation services. Drawing on peer-reviewed studies up to 2025, we illustrate the shift from simple, price-only bidding to more advanced mechanisms such as combinatorial, multi-round, and multi-attribute auctions. We present the core auction-design methods in different contexts, including Full Truckload and Less-than-Truckload operations in both strategic and spot markets. We finally discuss new trends in auction design for transportation services procurement.

• 
  16h20 - 16h45

  Sustainable Bid Generation and Contract Selection in Transportation Procurement Under Shipper-Specific Emission Constraints

  • Rekik Monia, Université Laval
  • Fourat Trabelsi, prés., Université Laval

  The increasing urgency of climate change and the tightening of environmental regulations have significantly transformed transportation procurement practices. Traditional approaches to bid generation in transportation services procurement auctions have largely focused on economic objectives and fall short of satisfying the growing demands of environmentally conscious shippers and evolving regulatory frameworks. To bridge this gap, we propose a novel optimization model that explicitly incorporates sustainability considerations into the bid generation and contract selection process. We introduce a structured approach to represent shipper-specific environmental requirements, whereby each shipper imposes a maximum allowable average emission rate—measured in CO₂ emissions per ton-kilometer—on the set of bids submitted by carriers. The model accounts for fleet heterogeneity, capturing the operational and environmental characteristics of electric, hybrid, and internal combustion engine vehicles. By optimizing contract selection and fleet assignment jointly, the model allows carriers to balance profit maximization, regulatory compliance, and carbon efficiency. This dual focus enables carriers to meet diverse shipper requirements, maintain competitiveness, and contribute to sustainable logistics practices.

• 
  16h45 - 17h10

  Carriers' selection and shipments assignment for tactical transportation planning under dynamic stochastic demand

  • Simon Schmiedel, Université Laval
  • Rania Boujemaa, Université Laval
  • Monia Rekik, prés., Université Laval
  • Hajji Adnene, Université Laval

  We consider a Carrier's Selection and Shipment Assignment Problem (CSSAP) in a distribution network where a set of products need to be shipped from warehouses to distribution centers to satisfy the demand at each distribution center at each period of a tactical planning horizon. The demand at distribution centers is uncertain and back-ordering is permitted but penalized. Shipments are ensured by external carriers either strategic or spot ones. Strategic carriers are long-term contracts carriers with commitments to respect when solving the CSSAP.
  The problem is formulated as a multi-stage dynamic stochastic model. In this talk, we will present the new variants of the Stochastic Dual Dynamic Programming (SDDP) algorithm we propose to solve the problem. Our results show that the SDDP algorithm is a good approach to solve the CSSAP under different contexts yielding good-quality solutions in a reasonable time. In this talk, we will also show how some of the new variants of the SDDP algorithm we propose outperform existing ones.