Postdoc In Symmetry Handling in Bilevel Programming

Introduction

Bilevel programming (BP) is a powerful mathematical framework for modeling hierarchical decision-making processes involving two players: a leader and a follower. In energy network design, for example, the leader aims to build a robust network that mitigates failures caused by the follower’s actions. A key characteristic of such applications is the presence of symmetries. For instance, a symmetric network naturally leads to symmetric failure scenarios, which are reflected in BP models. However, current BP software can neither detect nor exploit these symmetries. As a result, despite BP’s strong modeling capabilities, existing technology can only handle relatively small-scale problems.

Job Description

In the SymBi project (Exploiting Symmetries for Faster Bilevel Optimization Algorithms), we address this limitation by developing a general mathematical theory of symmetries in BP and efficient algorithms for symmetry detection and exploitation. While the related field of mixed-integer programming (MIP) primarily uses symmetries to eliminate redundant parts of the solution space, SymBi goes further: it aims to enhance other components of BP solvers, such as cutting planes, to achieve a stronger coupling between leader and follower decisions.

We are seeking for a motivated and enthusiastic Postdoc (PD) researcher to join the Combinatorial Optimization group (https://www.tue.nl/en/research/research-groups/mathematics/statistics-probability-and-operations-research/combinatorial-optimization-1) under the supervision of dr. Christopher Hojny, assistant professor. The research activities of the PD will include

• defining a mathematically sound notion of symmetries for bilevel optimization problems,
• developing a novel theory for exploiting symmetries that is tailored for bilevel optimization problems, and
• implementing and testing the developed algorithms for solving benchmark problems.

Next to the research tasks, the PD will be asked to assist, for a small percentage of their time, with educational tasks (course support and supervision of students).

The SymBi project is a collaborative project between dr. Christopher Hojny (Eindhoven University of Technology) and prof. dr. Martin Schmidt (Trier University, Germany). Both groups will work closely together on the project to create synergies between the different expertise of the different groups. This synergy will not only yield a novel theoretical foundation for symmetries in BP but also advance state-of-the-art BP software—enabling researchers and practitioners in fields such as economics and engineering to solve complex problems significantly faster.

Job Requirements

• Motivated researcher, with a PhD in integer programming, bilevel programming, mathematical optimization, or a comparable domain.
• Very good programming skills, preferably in C/C++.
• Ability to conduct high quality academic research, reflected in demonstrable outputs.
• A team player who enjoys coaching PhD and Master's students and working in a dynamic, interdisciplinary team.
• A proven ability to manage complex projects to completion on schedule.
• Excellent (written and verbal) proficiency in English, good communication skills (knowledge of the Dutch language is not required).

Conditions of Employment

A meaningful job in a dynamic and ambitious university, in an interdisciplinary setting and within an international network. You will work on a beautiful, green campus within walking distance of the central train station. In addition, we offer you:

• Full-time employment for 3 years. Please note that for a postdoc position, our departmental policy is that we offer a one-year contract first, which is extended based on good performance.
• Salary in accordance with the Collective Labour Agreement for Dutch Universities, scale 10 (min. € 4,241 max. € 5,538).
• A year-end bonus of 8.3% and annual vacation pay of 8%.
• High-quality training programs on general skills, didactics and topics related to research and valorization.
• An excellent technical infrastructure, on-campus children's day care and sports facilities.
• Partially paid parental leave and an allowance for commuting, working from home and internet costs. 
• A TU/e Postdoc Association that helps you to build a stronger and broader academic and personal network, and offers tailored support, training and workshops.
• A Staff Immigration Team is available for international candidates, as are a tax compensation scheme (the 30% facility) and a compensation for moving expenses.

About us

Eindhoven University of Technology is a leading international university within the Brainport region where scientific curiosity meets a hands-on mindset. We work in an open and collaborative way with high-tech industries to tackle complex societal challenges. Our responsible and respectful approach ensures impact — today and in the future. TU/e is home to over 13,000 students and more than 7,000 staff, forming a diverse and vibrant academic community.

With over 110 (assistant, associate and full) professors, almost 300 PhD and EngD students, about 1500 Bachelor students and 1000 Master students, the Department of Mathematics and Computer Science (M&CS) is the largest department of the TU/e. By performing top-level fundamental and applied research, and maintaining strong ties with industry, M&CS aims to contribute to science and innovation in and beyond the region.

Information

Do you recognize yourself in this profile and would you like to know more? Please contact the hiring manager Christopher Hojny, Assistant Professor, c.hojny@tue.nl.

Visit our website for more information about the application process or the conditions of employment.

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Application

We invite you to submit a complete application using the apply-button. The application should include a:

• Cover letter in which you describe your motivation and qualifications for the position.
• Curriculum vitae, including a list of your publications and the contact information of three references. Kindly note that we may reach out to references at any stage of the recruitment process. We recommend notifying your references upon submitting your application.
• List of up to five self-selected ‘best publications’.

Ensure that you submit all the requested application documents. Please note that incomplete applications may not be considered and could be rejected.

We give priority to complete applications.

We look forward to receiving your application and will screen it as soon as possible. The vacancy will remain open until the position is filled.

Please note

• You can apply online. We will not process applications sent by email and/or post. 
• A pre-employment screening (e.g. knowledge security check) can be part of the selection procedure. For more information on the knowledge security check, please consult the National Knowledge Security Guidelines.
• Please do not contact us for unsolicited services.