activity
20212026
collaborators

10 papers

math.OC2026

On the Computational Complexity of Bilevel Integer Linear Programming

Nagisa Sugishita, Margarida Carvalho

We investigate the computational complexity of bilevel integer linear programming. While Jeroslow~(1985) established that the decision version of this problem is -complete w…

math.OC2026

Price of Coupling in Multilevel Linear Programming

Nagisa Sugishita, Margarida Carvalho

Multilevel programming is the standard framework for modeling hierarchical decision-making. In this paper, we characterize the computational complexity of deciding the existence of…

math.OC2026

Decision Problems in Multilevel Linear Programming

Nagisa Sugishita, Margarida Carvalho

We study the computational complexity of decision problems in -level linear programming (LP). Seminal work by Jeroslow establishes that determining whether the optimal objective…

eess.SY2025

Competitive EV charging station location with queues

The Minh Nguyen, Nagisa Sugishita, Margarida Carvalho +1

Electric vehicle (EV) public charging infrastructure planning faces significant challenges in competitive markets, where multiple service providers affect congestion and user behav…

math.OC2025

The Branch-and-Bound Tree Closure

Marius Roland, Nagisa Sugishita, Alexandre Forel +3

This paper investigates the a-posteriori analysis of Branch-and-Bound~(BB) trees to extract structural information about the feasible region of mixed-binary linear programs. We int…

math.OC2025

Complexity of Bilevel Linear Programming with a Single Upper-Level Variable

Nagisa Sugishita, Margarida Carvalho

Bilevel linear programming (LP) is one of the simplest classes of bilevel optimization problems, yet it is known to be NP-hard in general. Specifically, determining whether the opt…