no code implementations • 28 Apr 2016 • Shunji Umetani
We present a data mining approach for reducing the search space of local search algorithms in a class of binary integer programs including the set covering and partitioning problems.
no code implementations • 14 May 2017 • Shunji Umetani, Masanao Arakawa, Mutsunori Yagiura
For the conventional SCP, the pricing method has been introduced to reduce the size of instances, and several efficient heuristic algorithms based on such reduction techniques have been developed to solve large-scale instances.
no code implementations • 10 Nov 2018 • Naoya Uematsu, Shunji Umetani, Yoshinobu Kawahara
Nemhauser and Wolsey developed an exact algorithm called the constraint generation algorithm that starts from a reduced BIP problem with a small subset of constraints taken from the constraints and repeats solving a reduced BIP problem while adding a new constraint at each iteration.
no code implementations • 26 Apr 2019 • Naoya Uematsu, Shunji Umetani, Yoshinobu Kawahara
For the problem of maximizing an approximately submodular function (ASFM problem), a greedy algorithm quickly finds good feasible solutions for many instances while guaranteeing ($1-e^{-\gamma}$)-approximation ratio for a given submodular ratio $\gamma$.
no code implementations • 9 Apr 2021 • Shunji Umetani, Shohei Murakami
We consider the irregular strip packing problem of rasterized shapes, where a given set of pieces of irregular shapes represented in pixels should be placed into a rectangular container without overlap.
