BME KJK | Department of Material Handling and Logistics Systems

Innovative modeling and sizing methods of the city logistics systems of urban concentrated sets of delivery locations

Experts currently working on the project: Dávid Lajos Sárdi, Krisztián Bóna, Ph.D., György Lipovszki, Ph.D. (simulations expert)

Experts who helped in the project: Bálint Bertalan

Past participants of the project: István Bence Kövér

Start of the project: February 2019

In the case of urban concentrated sets of delivery locations, there are several delivery locations in a relatively small urban area that cause a significant logistics burden on the life of cities. These processes can significantly damage urban infrastructure, lead to severe environmental and noise pollution, and require substantial resources. Both Hungarian and international research results clearly demonstrate that the development of new, multi-stage city logistics systems based on the gateway concept can reduce the load caused by the concentrated sets of delivery locations and make the logistics processes that meet the requirements more efficient in several aspects. However, the optimal design of these systems raises many unanswered questions and measuring problems. As a result, significant resources are also concentrated internationally for research and development in this area.

The main goal of this research is to develop a generally interpretable mathematical and simulation model to examine the performance and cost parameters of the current logistics system and new, gateway concept-based solutions for any type of concentrated set of delivery locations, whether a market or a large shopping area and the results should be used to determine the appropriate system architecture.

The main tasks of the research project were the followings:

  • Developing new, gateway-concept-based solutions for the supply system of concentrated sets of delivery points
  • Developing mathematical and simulation models of the current supply system and its cost structure of concentrated sets of delivery points
  • Developing mathematical and simulation model of the new, gateway-concept-based supply system and its cost structure of concentrated sets of delivery points
  • Defining the logistics system architecture, which is capable of being for the supply system of urban concentrated sets of delivery points based on the simulation results
  • Development of a pilot simulation model in Python (as a discrete event-based simulator) for the current and new supply system of urban concentrated sets delivery locations
      • Python-based pilot simulation model of the current supply system completed with two stores, two suppliers, four products and cross-connections
      • Python-based pilot simulation model of the future supply system completed with two stores, two suppliers, four products and cross-connections
      • Indicators to be measured during the modeling of the current system have been defined
      • The Python model of the current system has been parameterized
      • Many experiments have been carried out on the Python-based model of the current system, focusing on the expected runtime of the sub-models and full models of different sizes based on running the pilot model and the extent to which the model needs to be accelerated in the future
      • Based on the obtained results and our experience, we have developed and accelerated the model at several points, so the model is suitable for running entire shopping mall processes in a few hours
      • Based on the 2-store pilot model, we have created 32-, 64-, 128- and 256-store pilot models to test larger groups of stores and smaller, medium, and large shopping malls (and any concentrated sets of delivery locations)
      • The performance of the pilot models was tested with two sets of parameters, one for smaller volumes (boxes) and one for larger volumes (pallet units), and the runtime results show that the Python-based model is suitable for microscopic-level examination of the current city logistics system for concentrated demand point sets

Regarding Python-based simulation modeling, György Lipovszki, Ph.D. is helping us, and we would like to thank him again.

Regarding speeding up the model, Bálint Bertalan helped us, and we would like to thank him as well.

Objects and relationships in the modeled current pilot supply system

The pilot simulation model of the current logistics system in Python, in the Spyder development environment

Significant documents related to the project

Krisztián Bóna, György Lipovszki, Dávid Lajos Sárdi. Python-based simulation modelling of the city logistics system of the concentrated sets of delivery locations (2021).
Hungarian Logistics Association – Logistics Yearbook 2021, pp. 115-127.
URL: https://mle.hu/logisztikai-evkonyv-2021/
DOI: 10.23717/LOGEVK.2021.12
ISSN: 1218-3849

Krisztián Bóna, Dávid Lajos Sárdi. Mesoscopic simulation model of the logistics system of concentrated sets of urban delivery locations (2021).
International Journal of Simulation and Process Modelling, 16 (2), pp. 116-129.
URL: http://www.inderscience.com/offer.php?id=115865
DOI: 10.1504/IJSPM.2021.115865
ISSN 1740-2123

Dávid Lajos Sárdi. Consolidation-based city logistics developments in the system of the concentrated sets of delivery locations (2022).
Budapest University of Technology and Economics, Faculty of Transportation Engineering and Vehicle Engineering, Kandó Kálmán Doctoral School, PhD dissertation.
Full document in Hungarian: https://repozitorium.omikk.bme.hu/bitstream/handle/10890/25934/ertekezes.pdf?sequence=2&isAllowed=y
Thesis booklet in English: https://repozitorium.omikk.bme.hu/bitstream/handle/10890/25934/tezis_eng.pdf?sequence=4&isAllowed=y

Dávid Lajos Sárdi. Consolidation-based developments in the city logistics system of the concentrated sets of delivery locations (2022).
Budapest University of Technology and Economics, BMe Research Grant.
URL: http://doktori.bme.hu/bme_palyazat/2022/honlap/Sardi_David_Lajos_en.htm

Dávid Lajos Sárdi, György Lipovszki, Krisztián Bóna. Application of microscopic discrete event-based simulation in the modeling of the city logistics systems of concentrated sets of delivery locations (2023).
Journal of Simulation (online publication).
URL: https://www.tandfonline.com/doi/full/10.1080/17477778.2023.2272967
DOI: 10.1080/17477778.2023.2272967
ISSN: 1747-7778

György Lipovszki. Discrete Event Simulator (DES) in Python Programming Environment – User manual (2023).
Budapest, 02/11/2023
URL: https://www.logisztika.bme.hu/wp-content/uploads/2023/11/2023-11-08__FULL_DES_Python_User_Manual_ENG.pdf