GIPS is an open-source framework for Graph-Based (M)ILP Problem Specification. This repository holds the GIPS implementation projects and additional documentation for the Integrated Healthcare Timetabling Problem (IHTP) paper 2025:

High-Level Specification of MILP Problems with Class Diagrams and Graph Transformations: A Case Study in Model-Driven Optimisation of the Integrated Healthcare Timetabling Problem. Maximilian Kratz, Jule Pfau, Steffen Zschaler, Jens Kosiol, and Andy Schürr. 2025.

Our complete problem description and modelling approach of section 3 of the paper is documented in problem-description.md.

Our complete solution specification of section 4 of the paper is documented in solution-description.md.

The implementation described in section 4 and 5 of the paper can be found in the folder implementation.

The necessary steps to set up the implementation are listed below.

• Install GIPS as described in its repository.
• Launch a runtime workspace (while using a runtime Eclipse) as stated in the eMoflon::IBeX installation steps. (Please refer to the installation steps of GIPS above.)
• Use this PSF file to import all IHTP-related projects.
• Build all your projects with the black eMoflon hammer. Sometimes, it is required to trigger a cleaning in Eclipse (Project -> Clean... -> Clean all projects).
• Some of the examples have a runnable Java class with a main function.
• You can now launch the GIPS project ihtcvirtualrunner:
  • Go to ihtcvirtualrunner -> src -> org.emoflon.gips.ihtc.virtual.runner.cli in the project explorer.
  • Execute the main method of the class IhtcVirtualGipsHeadlessRunner.java and provide the explained arguments.

This project is licensed under the GNU General Public License v3.0 - see the LICENSE file for more details.