Selin Atac

Journal publications [3]

2025

Atac S., Obrenovic N., Bierlaire M. (2025). Bike Sharing Systems: The Impact of Precise Trip Demand Forecasting on Operational Efficiency in Different City Structures . Journal of Cycling and Micromobility Research 3 (100058)

Increasing environmental concerns drive interest in sustainable solutions across various fields. Vehicle sharing systems such as one-way station-based bike sharing systems (BSSs) offer one such solution in transportation, although they pose operational challenges like vehicle imbalance. While many studies focus on optimizing rebalancing operations using trip demand forecasting, the added value of precise trip demand forecasting remains unexplored. This study assesses the added value of collecting detailed trip demand data and developing trip demand forecasting models. To achieve this, we create a simulation–optimization framework representing a city BSS in operation during the day. We use a discrete-event simulator representing the system dynamics and an enhanced mathematical model optimizing the rebalancing operations. We employ clustering in the optimization module to manage larger case studies, dividing the problem into smaller sub-problems. Our computational experiments compare two main scenarios, perfect demand forecast and unknown future demand, as well as several intermediate scenarios where partial future trip demand information is available. These scenarios allow us to determine the trade-off between lost trip demand and rebalancing operations costs, assess demand forecasting benefits, and identify the budget’s upper limit for precise trip demand forecasting. Subsequently, we conduct experiments on one synthetic (35 stations) and four real-life case studies, ranging from small systems (21 and 298 stations) to large systems (681 and 1361 stations). Results reveal that precise trip demand forecasting has varying impacts on small and large BSSs, with larger BSSs benefiting the most without significantly increasing the rebalancing operations costs. We also observe that the most significant improvements occur between 0% and 40% trip demand knowledge while beyond 60%, the increase in returns diminishes. The findings of this study offer valuable insights for operators in enhancing service levels and optimizing resource allocation.
```
@Article{AtacObreBier25,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Bike Sharing Systems: The Impact of Precise Trip Demand Forecasting on Operational Efficiency in Different City Structures 

},
  journal = {Journal of Cycling and Micromobility Research},
  year = {2025},
  volume = {3},
  number = {100058},
  DOI = {10.1016/j.jcmr.2025.100058},
  note = {Accepted on Jan 21, 2025}}}
```

2024

Obrenovic N., Atac S., Bierlaire M. (2024). Light electric vehicle sharing systems: Functional design of a comprehensive decision making solution. Transportation Research Part A: Policy and Practice 182 (104043)

The functional design of a decision support system for a state-of-the-art vehicle sharing system (VSS) inevitably includes the selection or definition of methodologies for planning and managing the observed VSS. In this paper, our focus is on an innovative VSS that utilizes light electric vehicles. Our goal is to specify the functions of a comprehensive decision making solution for such a VSS through a qualitative and systematic literature and system analysis. To achieve this goal, we rely on the holistic VSS management framework developed in our previous research. As a result of our study, we identify possible solution methodologies or algorithms for implementing functions of the designed decision making solution, and propose the necessary adjustments for their application in the case of light electric vehicles, or note any research gap. With these findings, we provide justified guidance to practitioners in creating these solutions, with the aim of reducing development time.
```
@Article{ObreAtacBier24,
  author = {Nikola Obrenovic and Selin Atac and Michel Bierlaire},
  title = {Light electric vehicle sharing systems: Functional design of a comprehensive decision making solution},
  journal = {Transportation Research Part A: Policy and Practice},
  year = {2024},
  volume = {182},
  number = {104043},
  DOI = {10.1016/j.tra.2024.104043},
  note = {Accepted on Mar 09, 2024}}}
```

2021

Atac S., Obrenovic N., Bierlaire M. (2021). Vehicle Sharing Systems: A Review and a Holistic Management Framework. EURO Journal on Transportation and Logistics 10 (100033)

Although different vehicle sharing systems (VSSs) use different vehicle types, the management challenges and optimization problems to be solved are similar or even the same. This observation led us to create a generalized and holistic VSS management framework, which aims to be applicable to the system using any vehicle type. The framework components, their mutual relationships, and framework tasks have been identified through a thorough and systematic literature review. Furthermore, the literature is positioned in the line with the framework. Finally, the framework and systematic literature review allowed us to identify gaps in the literature, and interesting research avenues.
```
@Article{AtacObreBier21,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Vehicle Sharing Systems: A Review and a Holistic Management Framework},
  journal = {EURO Journal on Transportation and Logistics},
  year = {2021},
  volume = {10},
  number = {100033},
  DOI = {10.1016/j.ejtl.2021.100033},
  note = {Accepted on Feb 24, 2021}}}
```

Book chapters [2]

2023

Atac S., Obrenovic N., Bierlaire M. (2023) A General Framework to Evaluate Different Rebalancing Operations Strategies in One-Way Car Sharing Systems. In Grothe, O., Nickel, S., Rebennack, S., Stein, O. (ed) Operations Research Proceedings 2022. OR 2022., Springer [ISBN 978-3-031-24906-8]


@InProceedings{AtacObreBier,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {A General Framework to Evaluate Different Rebalancing Operations Strategies in One-Way Car Sharing Systems},
  year = {2023},
  booktile = {Operations Research Proceedings 2022. OR 2022.},
  editor = {Grothe and  O. and  Nickel and  S. and  Rebennack and  S. and  Stein and  O.},
  series = {Lecture Notes in Operations Research},
  publisher = {Springer}}}

Obrenovic N., Atac S., Bortolomiol S., Brdar S., Marko O., Crnojevic V. (2023) The Crop Plant Scheduling Problem. In Cappanera, P., Lapucci, M., Schoen, F., Sciandrone, M., Tardella, F., Visintin, F. (ed) Optimization and Decision Science: Operations Research, Inclusion and Equity, Springer [ISBN 978-3-031-28862-3]


@InProceedings{ObreAtacBortBrdaMarkCrno23,
  author = {Nikola Obrenovic and Selin Atac and Stefano Bortolomiol and Sanja Brdar and Oskar Marko and Vladimir Crnojevic},
  title = {The Crop Plant Scheduling Problem},
  year = {2023},
  booktile = { Optimization and Decision Science: Operations Research, Inclusion and Equity},
  editor = {Cappanera and  P. and  Lapucci and  M. and  Schoen and  F. and  Sciandrone and  M. and  Tardella and  F. and  Visintin and  F.},
  volume = {9},
  series = {AIRO Springer Series},
  publisher = {Springer}}}

Articles in conference proceedings [8]

2022

Obrenovic N., Atac S., Bortolomiol S., Brdar S., Marko O., Crnojevic V. (2022) The crop plant scheduling problem. Proceedings of the Italian OR Days 2022 (GOR), 30 August-02 September, Florence, Italy


@InProceedings{ObrAtaBor_ItalianOR2022,
  author = {Nikola Obrenovic and Selin Atac and Stefano Bortolomiol and Sanja Brdar and Oskar Marko and Vladimir Crnojevic},
  title = {The crop plant scheduling problem},
  booktime = {Proceedings of the Italian OR Days 2022 (GOR), 30 August-02 September},
  year = {2022},
  address = {Florence, Italy}}}

Atac S., Obrenovic N., Bierlaire M. (2022) A general framework to evaluate different rebalancing operations strategies in one-way car sharing systems. Proceedings of the International Conference on Operations Research (OR 2022), 06-09 September, Karlsruhe, Germany


@InProceedings{AtaObrBie_GermanOR2022_v0,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {A general framework to evaluate different rebalancing operations strategies in one-way car sharing systems},
  booktime = {Proceedings of the  International Conference on Operations Research (OR 2022), 06-09 September},
  year = {2022},
  address = {Karlsruhe, Germany}}}

Atac S., Obrenovic N., Bierlaire M. (2022) Evaluating different strategies to solve rebalancing operations in car sharing systems. Proceedings of the 22nd Swiss Transport Research Conference (STRC), 18-20 May, Ascona, Switzerland


@InProceedings{AtaObrBie_STRC2022,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Evaluating different strategies to solve rebalancing operations in car sharing systems},
  booktime = {Proceedings of the 22nd Swiss Transport Research Conference (STRC), 18-20 May},
  year = {2022},
  address = {Ascona, Switzerland}}}

2021

Atac S., Obrenovic N., Bierlaire M. (2021) A multi-objective approach for station clustering in bike sharing systems. Proceedings of the 21st Swiss Transport Research Conference (STRC), 12-14 September, Ascona, Switzerland


@InProceedings{AtaObrBie_STRC2021,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {A multi-objective approach for station clustering in bike sharing systems},
  booktime = {Proceedings of the 21st Swiss Transport Research Conference (STRC), 12-14 September},
  year = {2021},
  address = {Ascona, Switzerland}}}

2020

Atac S., Obrenovic N., Bierlaire M. (2020) Bike Sharing Systems: Does demand forecasting yield a better service?. Proceedings of the 9th Symposium of the European Association for Research in Transportation (hEART), 3-4 February 2021, Lyon, France


@InProceedings{AtaObrBie_hEART2020,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Bike Sharing Systems: Does demand forecasting yield a better service?},
  booktime = {Proceedings of the 9th Symposium of the European Association for Research in Transportation (hEART), 3-4 February 2021},
  year = {2020},
  address = {Lyon, France}}}

Atac S., Obrenovic N., Bierlaire M. (2020) Vehicle sharing systems: Does demand forecasting yield a better service?. Proceedings of the 20th Swiss Transport Research Conference (STRC), 13-14 May, Ascona, Switzerland


@InProceedings{AtaObrBie_STRC2020,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Vehicle sharing systems: Does demand forecasting yield a better service?},
  booktime = {Proceedings of the 20th Swiss Transport Research Conference (STRC), 13-14 May},
  year = {2020},
  address = {Ascona, Switzerland}}}

2019

Atac S., Obrenovic N., Bierlaire M. (2019) A holistic decision making framework for a vehicle sharing system. Proceedings of the 23rd European Conference on Advances in Databases and Information Systems (ADBIS), 08-11 September, Bled, Slovenia


@InProceedings{AtaObrBie_ADBIS2019,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {A holistic decision making framework for a vehicle sharing system},
  booktime = {Proceedings of the 23rd European Conference on Advances in Databases and Information Systems (ADBIS), 08-11 September},
  year = {2019},
  address = {Bled, Slovenia}}}

Atac S., Obrenovic N., Bierlaire M. (2019) An optimization framework for light electric vehicle sharing systems. Proceedings of the 19th Swiss Transport Research Conference (STRC), 15-17 May, Ascona, Switzerland


@InProceedings{AtaObrBie_STRC2019,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {An optimization framework for light electric vehicle sharing systems},
  booktime = {Proceedings of the 19th Swiss Transport Research Conference (STRC), 15-17 May},
  year = {2019},
  address = {Ascona, Switzerland}}}

Talks [12]

2022

Atac S., Obrenovic N., Bierlaire M. A general framework to evaluate different rebalancing operations strategies in one-way car sharing systems September 07, 2022. German OR Days 2022 (GOR 2022), Karlsruhe, Germany.


@Misc{Atac_GermanOR2022,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {A general framework to evaluate different rebalancing operations strategies in one-way car sharing systems},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_GermanOR2022.pdf}},
  year = {2022},
  note = {Presented at German OR Days 2022 (GOR 2022), Karlsruhe, Germany}}}

Atac S., Obrenovic N., Bierlaire M. Evaluation of demand forecasting in bike sharing systems: A general framework and selected case studies June 23, 2022. 11th Triennial Symposium on Transportation Analysis (TRISTAN XI), Mauritius.


@Misc{Atac_TRISTAN2022,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Evaluation of demand forecasting in bike sharing systems: A general framework and selected case studies},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_TRISTAN2022.pdf}},
  year = {2022},
  note = {Presented at 11th Triennial Symposium on Transportation Analysis (TRISTAN XI), Mauritius}}}

Atac S., Obrenovic N., Bierlaire M. Comparing different rebalancing operations strategies in car sharing systems: A generic optimization framework June 03, 2022. 18th Swiss Operations Research Days, Zurich University of Applied Sciences (ZHAW), Winterthur, Switzerland.


@Misc{Atac_SwissOR2022,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Comparing different rebalancing operations strategies in car sharing systems: A generic optimization framework},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_SwissOR2022.pdf}},
  year = {2022},
  note = {Presented at 18th Swiss Operations Research Days, Zurich University of Applied Sciences (ZHAW), Winterthur, Switzerland}}}

Atac S., Obrenovic N., Bierlaire M. Evaluating different strategies to solve rebalancing operations in car sharing systems May 19, 2022. 22nd Swiss Transport Research Conference (STRC), Monte Verità, Ascona, Switzerland.


@Misc{Atac_STRC2022,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Evaluating different strategies to solve rebalancing operations in car sharing systems},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_STRC2022.pdf}},
  year = {2022},
  note = {Presented at 22nd Swiss Transport Research Conference (STRC), Monte Verit\à, Ascona, Switzerland}}}

2021

Atac S., Obrenovic N., Bierlaire M. Designing a MATSim environment for a one-way car sharing system as a transport mode October 27, 2021. INFORMS Annual Meeting 2021, Anaheim, California, USA.


@Misc{Atac_INFORMS2021,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Designing a MATSim environment for a one-way car sharing system as a transport mode},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_INFORMS2021.pdf}},
  year = {2021},
  note = {Presented at INFORMS Annual Meeting 2021, Anaheim, California, USA}}}

Atac S., Obrenovic N., Bierlaire M. Demand-based operations of vehicle sharing systems October 15, 2021. Seminar at the C2SMART Lab, New York University, New York City, New York, US.


@Misc{Atac_C2SMART2021,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Demand-based operations of vehicle sharing systems},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_C2SMART2021.pdf}},
  year = {2021},
  note = {Presented at Seminar at the C2SMART Lab, New York University, New York City, New York, US}}}

Atac S., Obrenovic N., Bierlaire M. A multi-objective approach for station clustering in bike sharing systems September 14, 2021. 21st Swiss Transport Research Conference (STRC), Monte Verità, Ascona, Switzerland.


@Misc{Atac_STRC2021,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {A multi-objective approach for station clustering in bike sharing systems},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_STRC2021.pdf}},
  year = {2021},
  note = {Presented at 21st Swiss Transport Research Conference (STRC), Monte Verit\à, Ascona, Switzerland}}}

2020

Atac S., Obrenovic N., Bierlaire M. Vehicle sharing systems: Does demand forecasting yield a better service? May 13, 2020. 20th Swiss Transport Research Conference (STRC), Monte Verità, Ascona, Switzerland.


@Misc{Atac_STRC2020,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {Vehicle sharing systems: Does demand forecasting yield a better service?},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_STRC2020.pdf}},
  year = {2020},
  note = {Presented at 20th Swiss Transport Research Conference (STRC), Monte Verit\à, Ascona, Switzerland}}}

2019

Atac S., Obrenovic N., Bierlaire M. A new framework for a vehicle sharing system September 04, 2019. German OR days 2019, Technische Universität Dresden, Dresden, Germany.


@Misc{Atac_GermanOR2019,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {A new framework for a vehicle sharing system},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_GermanOR2019.pdf}},
  year = {2019},
  note = {Presented at German OR days 2019, Technische Universit\ät Dresden, Dresden, Germany}}}

Atac S., Obrenovic N., Bierlaire M. An optimization framework for a light electric vehicle sharing system June 24, 2019. EURO 2019, University College Dublin, Dublin, Ireland.


@Misc{Atac_EURO2019,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {An optimization framework for a light electric vehicle sharing system},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_EURO2019.pdf}},
  year = {2019},
  note = {Presented at EURO 2019, University College Dublin, Dublin, Ireland}}}

Atac S., Obrenovic N., Bierlaire M. A framework for a vehicle sharing system June 07, 2019. 17th Swiss Operations Research Days, University of Lausanne (UNIL), Lausanne, Switzerland.


@Misc{Atac_SwissOR2019,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {A framework for a vehicle sharing system},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_SwissOR2019.pdf}},
  year = {2019},
  note = {Presented at 17th Swiss Operations Research Days, University of Lausanne (UNIL), Lausanne, Switzerland}}}

Atac S., Obrenovic N., Bierlaire M. An optimization framework for a light electric vehicle sharing system May 17, 2019. 19th Swiss Transport Research Conference (STRC), Monte Verità, Ascona, Switzerland.


@Misc{Atac_STRC2019,
  author = {Selin Atac and Nikola Obrenovic and Michel Bierlaire},
  title = {An optimization framework for a light electric vehicle sharing system},
  howpublished = {\url{https://transp-or.epfl.ch/documents/talks/Atac_STRC2019.pdf}},
  year = {2019},
  note = {Presented at 19th Swiss Transport Research Conference (STRC), Monte Verit\à, Ascona, Switzerland}}}

Awards [1]

2021

Selin Atac. PhD mobility award 2021, Doctoral School Civil and Environmental Engineering (EDCE).
The PhD Mobility Award is given by the doctoral program in Civil and Environmental Engineering (EDCE) to encourage good PhD students within the program to go for an academic visit to an external research institution..

Reviewing [6]

EPFL courses [11]

Spring 2023

Decision-aid methodologies in transportation.
- Level: Master
- Section: Civil Engineering
- Lecturers: Fabian Torres, Evangelos Paschalidis
- Teaching assistants: Selin Atac, Tom Haering
Optimization and Simulation.
- Level: PhD
- Section: Doctoral program in Civil and Environmental Engineering
- Lecturers: Michel Bierlaire, Cloe Cortes Balcells, Selin Atac
- Webpage: http://transp-or.epfl.ch/courses/OptSim2023

Fall 2022

Introduction to optimization and operations research .
- Level: Bachelor
- Sections: Mechanical Engineering, Civil Engineering, Environmental Sciences and Engineering, Electrical and Electronics Engineering
- Lecturer: Michel Bierlaire
- Teaching assistants: Fabian Torres, Selin Atac, Marija Kukic, Negar Rezvany

Spring 2022

Decision-aid methodologies in transportation.
- Level: Master
- Section: Civil Engineering
- Lecturers: Tim Hillel, Nour Dougui
- Teaching assistants: Selin Atac, Janody Pougala, Marija Kukic, Negar Rezvany, Tom Haering
Optimization and Simulation.
- Level: PhD
- Section: Doctoral program in Civil and Environmental Engineering
- Lecturers: Michel Bierlaire, Silvia Varotto, Selin Atac, Cloe Cortes Balcells
- Webpage: http://transp-or.epfl.ch/courses/OptSim2022

Spring 2021

Decision-aid methodologies in transportation.
- Level: Master
- Section: Civil Engineering
- Lecturers: Tim Hillel, Nour Dougui
- Teaching assistants: Selin Atac, Janody Pougala, Marija Kukic, Negar Rezvany, Nicola Ortelli, Stefano Bortolomiol
- Webpage: https://transp-or.epfl.ch/courses/decisionAid2020/index.php

Fall 2020

Introduction to optimization and operations research .
- Level: Bachelor
- Sections: Mechanical Engineering, Civil Engineering, Environmental Sciences and Engineering, Electrical and Electronics Engineering
- Lecturer: Michel Bierlaire
- Teaching assistants: Nour Dougui, Selin Atac, Stefano Bortolomiol, Marija Kukic, None None, Gael Lederrey, Cloe Cortes Balcells, Negar Rezvany

Spring 2020

Decision-aid methodologies in transportation.
- Level: Master
- Section: Civil Engineering
- Lecturers: Tim Hillel, Nour Dougui
- Teaching assistants: Stefano Bortolomiol, Gael Lederrey, Selin Atac, Janody Pougala
- Webpage: https://transp-or.epfl.ch/courses/decisionAid2020/index.php

Fall 2019

Introduction to optimization and operations research .
- Level: Bachelor
- Sections: Mechanical Engineering, Civil Engineering, Environmental Sciences and Engineering, Electrical and Electronics Engineering
- Lecturer: Michel Bierlaire
- Teaching assistants: Nour Dougui, Selin Atac, Stefano Bortolomiol, Nicholas Molyneaux, Gael Lederrey
- Webpage: https://moodle.epfl.ch/course/view.php?id=14491

Spring 2019

Decision-aid methodologies in transportation.
- Level: Master
- Section: Civil Engineering
- Lecturers: Nikola Obrenovic, Tim Hillel
- Teaching assistants: Stefano Bortolomiol, Gael Lederrey, Selin Atac
- Webpage: http://transp-or.epfl.ch/courses/decisionAid2019/index.php

Fall 2018

Introduction � l'optimisation et � la recherche op�rationnelle.
- Level: Bachelor
- Sections: Mechanical Engineering, Civil Engineering, Environmental Sciences and Engineering, Electrical and Electronics Engineering
- Lecturer: Michel Bierlaire
- Teaching assistants: Nikola Obrenovic, Nour Dougui, Stefano Bortolomiol, Selin Atac, Gael Lederrey
- Webpage: http://transp-or.epfl.ch/courses/optimization2018/

Lectures [10]

2023

Nested logit; Aggregate forecasting.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Jan 30, 2023
- Lecturer: Cloe Cortes Balcells
- Assistants: Selin Atac, Tom Haering, Negar Rezvany

2022

Hybrid Choice Models.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Mar 11, 2022
- Lecturer: Silvia Varotto
- Assistants: Cloe Cortes Balcells, Selin Atac
Logit Mixtures; Combining RP and SP data.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Mar 09, 2022
- Lecturer: Janody Pougala
- Assistants: Selin Atac, Silvia Varotto
Nested Logit; Aggregate Forecasting.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Mar 08, 2022
- Lecturer: Selin Atac
- Assistants: Cloe Cortes Balcells, Tom Haering
Introduction; Logit Estimation and Testing.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Mar 07, 2022
- Lecturer: Cloe Cortes Balcells
- Assistants: Janody Pougala, Selin Atac, Negar Rezvany

2021

Logit Mixtures; Combining RP and SP data.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Feb 10, 2021
- Lecturer: Janody Pougala
- Assistant: Selin Atac
Nested Logit; Aggregate Forecasting.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Feb 09, 2021
- Lecturer: Selin Atac
- Assistant: Janody Pougala

2019

Bayesian Estimation; Individual Prediction.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Mar 27, 2019
- Lecturer: Rico Krueger
- Assistants: Tim Hillel, Selin Atac, Meritxell Pacheco
Nested Logit; Aggregate Forecasting.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Mar 25, 2019
- Lecturer: Selin Atac
- Assistants: Meritxell Pacheco, Yuki Oyama, Tim Hillel
Introduction; Logit Estimation; Specification Testing.
- Discrete Choice Analysis: Predicting Individual Behavior and Market Demand, EPFL, Lausanne, Switzerland
- Mar 24, 2019
- Lecturer: Tim Hillel
- Assistants: Meritxell Pacheco, Yuki Oyama, Selin Atac

MSc theses [2]

2019

Warehouse inventory management optimization in Rolex SA, Rym Karime (Civil Engineering)
- Supervision: Nikola Obrenovic, Selin Atac, Michel Bierlaire
- External expert: Bruno Delaborde

2018-2019

Innovative technologies for improvement of airport accessibility with the applications to Geneva Airport, Thibaut Guillaume Marie Richard (Civil Engineering)
- Supervision: Nikola Obrenovic, Selin Atac, Michel Bierlaire
- External expert: Philippe Canal, Virginie Marche

Semester projects [11]

2023

A detailed evaluation of the Via Sicura program, Mya Jamal Lahjouji (Civil Engineering)

Supervision: Nicola Ortelli, Selin Atac, Michel Bierlaire
This project aims at updating and improving the official evaluation of the Via Sicura road safety program.

2022-2023

Scenario generation for the multi-agent transport simulation toolkit, MATSim, Anne-Valerie Preto (Civil Engineering)

Supervision: Selin Atac, Nicola Ortelli, Michel Bierlaire
CSSs are becoming increasingly popular, primarily due to their financial and environmental advantages. However, they face many operational challenges, including inventory management of vehicles and parking spots, vehicle load balancing and redistribution, pricing strategies, and demand forecasting. If these challenges are not addressed properly, the CSS risks experiencing a significant loss of customers and therefore revenue. The literature consists of variety of works on CSSs especially focused on the rebalancing operations. On the other hand, it lacks the detailed comparison of different strategies of rebalancing operations at a disaggregate level. One approach to fill this gap is using an agent-based transport simulation. Such simulation toolkits allow analysis at the individual level and testing different configurations such as city and network structure. Therefore, in this study the student will review the literature to determine the main characteristics of the CSSs. In the first part of the project, she will work on creating representative scenarios for the multi-agent transport simulation toolkit, MATSim, based on the findings in the literature. These scenarios will be used to compare different rebalancing operations strategies where an optimization module is used. The second part of the project will be implementing analysis scripts that will provide useful information on the simulation results.

2022

Heuristic applications for rebalancing operations in one-way car sharing systems, Miguel Chastre Rodrigues[Internship]

Supervision: Selin Atac, Michel Bierlaire
CSSs are becoming increasingly popular, primarily due to their financial and environmental advantages. However, they face many operational challenges, including inventory management of vehicles and parking spots, vehicle load balancing and redistribution, pricing strategies, and demand forecasting. If these challenges are not addressed properly, the CSS risks experiencing a significant loss of customers and therefore revenue. The literature consists of variety of works on CSSs especially focused on the rebalancing operations. On the other hand, it lacks the detailed comparison of different strategies of rebalancing operations at a disaggregate level. One approach to fill this gap is using an agent-based transport simulation. Such simulation toolkits allow analysis at the individual level and testing different configurations such as city and network structure. Therefore, in this study the student will review the literature to determine two rebalancing strategies existing in CSSs. The student will then focus on developing heuristic algorithms to solve these problems as they are computationally expensive to solve with exact methods.

Comparing rebalancing operations in car sharing systems, Xinling Li (Civil Engineering)

Supervision: Selin Atac, Nicola Ortelli, Michel Bierlaire
A car sharing system (CSS) offers users to rent cars for a short period of time. The users are identified by an RFID card or through a mobile application. The price of the trip is generally determined according to trip duration and length. One of the challenges faced in such systems is the imbalance of the vehicles throughout the city. This problem is solved by forecasting the demand and rebalancing the vehicles to meet user demand. First, the student is going to review the literature related to rebalancing operations in CSSs. Then, she will design and/or implement different rebalancing strategies in order to test the effects of different characteristics of the city/region. In other words, different strategies (static, reactive, and proactive) for rebalancing operations will be tested for each scenario and the results will be used to drive to conclusions which explain the relation between the city structure, demand structure and the different strategies of rebalancing operations.

2021

Designing and implementing rebalancing operations in car sharing systems using MATSim, Alfio Simone Mosset (Civil Engineering)

Supervision: Selin Atac, Stefano Bortolomiol, Michel Bierlaire
In this project, we will focus on Vehicle sharing systems (VSSs). VSSs are becoming increasingly popular, primarily due to their financial and environmental advantages. However, they face many operational challenges, including inventory management of vehicles and parking spots, vehicle load balancing and redistribution, pricing strategies, and demand forecasting. If these challenges are not addressed properly, the VSS risks experiencing a significant loss of customers and therefore revenue. The literature consists of variety of works on VSSs especially focused on the rebalancing operations. On the other hand, the literature lacks the demand forecasting dimension of the VSSs since it is exhausting to collect the data to develop a demand model. This project will aim to address this problem in a different way. Instead of developing a demand model, we aim to simulate the demand structure using an open-source software MATSim (Multi-Agent Transport Simulation Toolkit). The student is expected to develop an environment in MATSim for a car sharing system (CSS) where the census data is used. Then, he will create different scenarios in order to test the effects of different characteristics of the city/region. She will then identify the cases in which the rebalancing operations are needed. The implementation of rebalancing operations will be adapted from the free floating application of MATSim. In other words, different strategies (static, reactive, and proactive) for rebalancing operations will be tested for each scenario and the results will be used to drive to conclusions which explain the relation between the city structure, demand structure and the different strategies of rebalancing operations.

2020-2021

Designing a MATSim environment for a vehicle sharing system as a transport mode, Paula Vogg (Civil Engineering)

Supervision: Selin Atac, Cloe Cortes Balcells, Michel Bierlaire
A vehicle sharing system (VSS) offers users to rent vehicles for a short period of time. The price of the trip is generally determined according to trip duration and length. These systems are becoming increasingly popular, primarily due to their financial and environmental advantages. However, VSSs face many operational challenges, including inventory management of vehicles and parking spots, vehicle load balancing and redistribution, pricing strategies, and demand forecasting. If these challenges are not addressed properly, the VSS risks experiencing a significant loss of customers and revenue. One of the challenges faced in such systems is the imbalance of the vehicles throughout the city. This problem is solved by forecasting the demand and rebalancing the vehicles to meet user demand. However, since it is exhausting to collect the data to develop a demand model, this project will make use of the Multi-Agent Transport Simulation Toolkit (MATSim) to build this environment. First, the student is going to review the literature related to VSSs and get familiar with MATSim software. The student is expected to develop an environment in MATSim for a VSS where the census data is used and the VSS is the only transport mode in the city other than walking. Then, she will create different scenarios in order to test the effects of different characteristics of the city/region. She will then identify the cases in which the rebalancing operations are needed. In other words, different strategies (static, reactive, and proactive) for rebalancing operations will be tested for each scenario and the results will be used to drive to conclusions which explain the relation between the city structure, demand structure and the different strategies of rebalancing operations.

2020

Optimizing Organizational Chart using local search method, Hugo Bocquet

Supervision: Nour Dougui, Selin Atac, Michel Bierlaire
The aim of this project is to produce a near optimal Organisational Chart for a real case study. This Organisational Chart should optimize the span of control of Management in the company by maximizing a coverage metric using clearly-dened manipulations of the organizational design. To achieve this goal a local search method will be used and the results should be compared to those given by an exact method (Simplex). We will in a rst phase apply the optimization method to a small sample of Organisational Chart without considering the role of the employees. In a second phase, the role of the employees should be considered and a larger Organisational Chart should be considered.

Optimal regulation of oligopolistic markets with discrete choice models of demand, Elodie Duliscouet, Paulin Raison, Yahya Basiouny (Mechanical Engineering)

Supervision: Stefano Bortolomiol, Selin Atac, Michel Bierlaire
This project is inspired by the ongoing research project titled 'New generation of demand-supply interaction models', funded by the Swiss National Science Foundation. In particular, the project aims at studying models to find optimal policies to regulate markets characterized by oligopolistic competition and in which consumers make a discrete choice among a finite set of alternatives. In this framework, consumers are modelled as utility maximizers, according to random utility theory. Suppliers are modelled as profit maximizers, according to the traditional microeconomic treatment. Market competition is modelled as a non-cooperative game, for which an epsilon-equilibrium solution is sought. Finally, the regulator can affect the behavior of all other agents, for instance by giving subsidies or imposing taxes. In transport markets, these interventions might target specific alternatives, to reduce externalities such as congestion or emissions, or specific segments of the population, to achieve social welfare objectives. The objective of the project is to analyze, implement and evaluate algorithms to solve realistic applications of this problem, with particular focus on the transportation sector.

2019-2020

Analysis of the value of demand forecasting within vehicle sharing systems, Jasso Espadaler (Civil Engineering)

Supervision: Selin Atac, Stefano Bortolomiol, Michel Bierlaire
Vehicle sharing systems (VSSs) are becoming increasingly popular, primarily due to their financial and environmental advantages. However, VSSs face many operational challenges, including inventory management of vehicles and parking spots, vehicle load balancing and redistribution, pricing strategies, and demand forecasting. If these challenges are not addressed properly, the VSS risks experiencing a significant loss of customers and revenue. Recently, new VSSs have been introduced which use light electric vehicles (LEVs). These systems face a number of unique challenges. For instance, demand forecasting for LEV sharing systems is more complex, as locations are not fixed and journeys can start and end at any allowable location. LEV sharing systems also serve a higher portion of the population since these type of vehicles do not require a driving license. As such, the existing techniques for analysing VSSs are not sufficient for these new systems. To address this need, one needs to forecast the future demand of this novel transportation mode. Since it is exhausting to collect the data to develop a demand model, this project will aim to identify the value of a demand model by using mathematical models tailored for rebalancing operations from the literature and simulations. As LEV systems are still in their infancy, data describing them is not yet available. Therefore, the student will use alternative data, including PubliBike bike-sharing system data, accounting for any potential differences in the analysis. Based on the findings from the literature, the student will analyse different mathematical models.

2019

Demand forecasting for a novel transportation mode, Denis Steffen (Mathematics)

Supervision: Selin Atac, Tim Hillel, Michel Bierlaire
The vehicle sharing systems (VSSs) are becoming more and more popular due to both economic and environmental effects. However, these systems mainly focus on two specific types of vehicles: bicycles and cars. Recently, some other types of vehicles (e.g. light electric vehicles) with some specific properties that distinguish them from cars and bicycles are introduced for use in such kind of systems. Therefore, they lack research in each component of the framework. The aim of this project is to forecast the demand for a novel transportation mode. The student should survey different types of approaches, such as ARIMA, to forecast demand in similar systems and compare them by identifying performance measures. Since the data for this specific transportation mode does not exist yet the student will be directed to use the taxi data, which shares many properties with the system of interest.

2018-2019

Railway infrastructure maintenance, Ludovica Sessa and Robert Abboud (Management of Technology and Financial Engineering)

Supervision: Stefano Bortolomiol, Selin Atac, Michel Bierlaire
Following this summer tragedy in Genoa, Italy, European states and governments became more aware of the importance of keeping their countries� infrastructure modern and maintained. This interdisciplinary project will particularly focus on the topic of railway infrastructure maintenance and will cover some legal, economic, social, political aspects related to this socio-economic problem. The goal of this project is to study the topic of railway infrastructure maintenance from two perspectives. Initially, a qualitative analysis will be performed to precisely define the scope of the research and the main factors that affect the planning of investments to maintain railways infrastructures. Based on the findings of the qualitative analysis, the students will then critically analyze existing mathematical models that generate maintenance schedules and optimal railway investments, and will propose a framework which will be applied on a real-life case study.