Global optimization for the multilevel European gas market system with nonlinear flow models on trees

Abstract

The European gas market is implemented as an entry-exit system, which aims to decouple transport and trading of gas. It has been modeled in the literature as a multilevel problem, which contains a nonlinear flow model of gas physics. Besides the multilevel structure and the nonlinear flow model, the computation of so-called technical capacities is another major challenge. These lead to nonlinear adjustable robust constraints that are computationally intractable in general. We provide techniques to equivalently reformulate these nonlinear adjustable constraints as finitely many convex constraints including integer variables in the case that the underlying network is tree-shaped. We further derive additional combinatorial constraints that significantly speed up the solution process. Using our results, we can recast the multilevel model as a single-level nonconvex mixed-integer nonlinear problem, which we then solve on a real-world network, namely the Greek gas network, to global optimality. Overall, this is the first time that the considered multilevel entry-exit system can be solved for a real-world sized network and a nonlinear flow model.

Intelligent Evaluation Method of Engineering Cost Feasibility Model Based on Internet of Things

“…In formula (5), the obtained correlation degrees are sorted, the greater the correlation degree, the more consistent the change trend of the j-th index and the cost, that is, the higher the influence of X j on X 0 . According to the rule of taking the larger one, the indicators with greater correlation are reserved.…”

“…BIM is a complete enterprise engineering information system model, which can integrate engineering information, processes, and human resources in all stages of the enterprise's entire life cycle and apply it to the same model; it is convenient for the comprehensive management and operation of enterprises, projects, and engineering parties [5,6]. This technology uses three-dimensional digital technology to accurately analyze and simulate the real situation and construction information of a large building and provides a coordinated and internally unified information model for the design and construction of the entire construction project.…”

A tractable multi-leader multi-follower peak-load-pricing model with strategic interaction

“…In [26], the authors provide a framework to analyze the interaction of gas producers and traders with the network operator in the context of the entry-exit system in a multilevel setup. First computational techniques and numerical results have been presented in [7,30,63]. Our framework is complementary to this approach in the sense that it is capable to analyze the important case of strategic interaction of firms, when making their booking and nomination decisions.…”