Graduation Project: Relaxing hard constraints in solver for nurse scheduling problem

ORTEC

Thesis Internship

Den Haag

Up to 40 hours

Starts all year through

Published on January 14, 2025

Job description

ORTEC helps many of the world's best-run organizations make better data-driven decisions. Our decision support software and data science expertise enable you to improve your business results and make a positive impact on the world.

Since hospitals (and other businesses) operate 24/7, their employees are required to work night shifts among other shift types. There are many labor laws governing the scheduling of night shifts to ensure employees get sufficient rest after. These rules also require enough rest in general on a daily and weekly basis. The complex rules combined with a wide range of personal preferences make for an interesting scheduling puzzle to solve using heuristics.

We currently aim to solve this problem using a heuristic that explores different solutions with local search. The current algorithm does not allow swaps (moves) that violate any of the hard constraints. Your challenge is to test which temporal violations lead to better final solutions, and to quantify the optimal penalty values that need to be used for relaxing them.


What can you expect to do?

• Review existing literature and methodologies related to the nurse scheduling problem, heuristics, and ways to relax hard constraints with penalties.

• Familiarize yourself with the (Dutch) labor laws and the existing dataset

• Design and implement ways to relax the hard constraints throughout the search process considering the difficulty of fixing each violation.

• Evaluate the impact on the algorithm based on the solution, runtime etc.


Who are you

  • You are a master student in Data Science, Operations Research, Econometrics, Applied Mathematics or another related field and looking for a graduation project.
  • You have experience with heuristics such as Variable Neighborhood Search.
  • You like programming and can hunt for bugs (in C# or willing to learn).
  • You are currently living in the Netherlands, studying at a Dutch University, and communicate fluently in Dutch or English, verbally and in writing.
  • You are available for a minimum of six months to a maximum of nine months, starting in first quarter of 2025.
  • You can travel to the office (in Zoetermeer) at least twice a week


What we offer

  • Entrance to the most passionate powerhouse in applied mathematics. We share a drive to use our problem-solving skills to improve our planet, from the world at large to our own backyard.
  • Inclusion in a company founded by graduate students back in 1981, which today still fosters its students by:

o Excellent supervision during your graduation project,

o Good internship allowance, laptop, and other office facilities,

o An open, kind, and fun culture.

o Access to Young ORTEC formal and informal events


The next steps:

If you're an enthusiastic graduate student seeking a hands-on experience that combines analytical thinking, multidisciplinary collaboration, and problem-solving, we invite you to join us on this exciting assignment by uploading your  CV, motivation letter and grade lists (BSc and MSc in PDF if applicable). The recruitment process will consist of two online assessments and an interview.


What to expect

We will help you to thrive in your field of expertise. We offer development programs, tailored to your individual needs and function requirements, including opportunities to attend courses and seminars. We offer challenging, practical hands-on experience with opportunities to work abroad. We operate in a flat organizational structure that keeps communication lines short. The atmosphere is open, informal, cooperative and positive. We employ over 1000 people in the Netherlands (HQ), Belgium, Germany, France, the U.K., Romania, Italy, the U.S., Australia, Brazil, Poland, Denmark and Singapore. Visit our website ortec.com to learn more about our solutions and clients’ experiences. Please do not use this vacancy as an acquisition opportunity.

Apply now