30-04-2026 - Lecture Hall H

PhD presentation

Hydroelastic wave impact on a flexible overhang

Marnix Bockstael

Extreme wave impacts can exert high loads on maritime structures, which can lead to damage or failure. Controlled, artificially generated wave impacts are therefore important tools for the study of the expected value and variability of these events. The dynamics of extreme wave impacts involve large free surface variations and responses of the impacted structure. The hydrodynamic loads and structural response depend on their coupled interaction (hydroelasticity), which should be taken into account.
I will present an experimental setup that was designed to include all of these phenomena. After an introduction to my research context, the effects of hydroelasticity on the (numerical) analysis of the physical experiment will be the main point of discussion.

30-04-2026 - Lecture Hall H

PhD presentation

Choice-Based Periodic Vehicle Routing and Pricing for Urban Last-Mile Deliveries

Ethan Yang

In urban periodic deliveries, business customers exhibit heterogeneous preferences over price, visit frequency, timing, and time window length. Ignoring such heterogeneity leads to service designs that misalign customer needs.
We propose the choice-based periodic vehicle routing and pricing problem (CB-PVRP), which incorporates stochastic customer choices into joint optimization of service offering, pricing, and vehicle routing. We formulate CB-PVRP as a two-stage stochastic mixed-integer program. The first stage determines offerings and pricing to maximize expected profit. The second stage, which embeds a bilevel structure, decides daily routing subject to revealed choices. We capture preference heterogeneity using a multinomial logit model with segmentation. We apply sample average approximation to address stochasticity and propose linear best-response sets for the bilevel reformulation.
Our tailored logic-based Benders decomposition algorithm outperforms a commercial solver on solution quality and speed. By incorporating customer choice behaviors, the provider achieves higher expected profitability while customers receive improved services.