Complex Urban Systems

complex urban systems group thumb image Topic leader: Nahid Mohajeri (currently Visiting Fellow, University of Oxford)
Scientist: Roberto Castello
PhD students: Dan Assouline, Alina Walch

Factsheet 2017-2018

In order to model the dynamics of built environment and understand their sustainable development, as well as their interactions with infrastructure networks and urban ecosystem we need a comprehensive theoretical understanding of cities as complex systems. One principal aim of this research is to use the complex system theories and methods from physics and engineering in order to reduce the negative environmental impact of the cities through the following approaches: (1) developing energy-efficient urban forms, (2) modelling and identifying renewable energy resources from regional to city scale, (2) improving our understanding of urban metabolism, (3) improving the environmental impacts of urban infrastructure networks and mobility patterns through data-driven approaches and real-time data (4) assessing and minimising the ecological footprints of cities.

Research interests include:

  • Statistical modelling of the built environment
  • Ecological footprints of cities
  • Urban metabolism
  • Physics of urban form
  • GIS and spatial data analysis
  • Urban morphology and renewable energy
  • Transportation networks and mobility patterns

Current projects

  • HYENERGY – Hybrid renewable energy potential for the built environment using big data
  • SCCER FEEB&D Current potential of renewable energy sources
  • Integrating urban form and sociotehcnical potentials of decentralised energy supply for sustainable urban development (SNSV Mobility fellowship Dr N Mohajeri – host institute University of Oxford)

Past projects

Specific research topics

Recent publications

Spatio-temporal modelling and uncertainty estimation of hourly global solar irradiance using Extreme Learning Machines

A. Walch; R. Castello; N. Mohajeri; F. Guignard; M. Kanevski et al. 

2019-03-15. 10 th International Conference on Applied Energy ( ICAE2018), Hong Kong , China, August 22- 25, 2018. p. 6378-6383. DOI : 10.1016/j.egypro.2019.01.219.

A solar-based sustainable urban design: The effects of city-scale street-canyon geometry on solar access in Geneva, Switzerland

N. Mohajeri; A. Gudmundsson; G. Knuckler; D. Assouline; J. Kämpf et al. 

Applied Energy. 2019. Vol. 240, p. 173-190. DOI : 10.1016/j.apenergy.2019.02.014.

Machine Learning and Geographic Information Systems for large-scale mapping of renewable energy potential

D. Assouline / J-L. Scartezzini; N. Mohajeri Pour Rayeni (Dir.)  

Lausanne: EPFL, 2019. DOI : 10.5075/epfl-thesis-9376.

Combining Fourier Analysis And Machine Learning To Estimate The Shallow-Ground Thermal Diffusivity In Switzerland

D. Assouline; N. Mohajeri; A. Gudmundsson; J-L. Scartezzini 

2018-01-01. 38th IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Valencia, SPAIN, Jul 22-27, 2018. p. 1144-1147.

Large-scale rooftop solar photovoltaic technical potential estimation using Random Forests

D. Assouline; N. Mohajeri; J. Scartezzini 

APPLIED ENERGY. 2018. Vol. 217, p. 189-211. DOI : 10.1016/j.apenergy.2018.02.118.

A city-scale roof shape classification using machine learning for solar energy applications

N. Mohajeri; D. Assouline; B. Guiboud; A. Bill; A. Gudmundsson et al. 

Renewable Energy. 2018. Vol. 121, p. 81-93. DOI : 10.1016/j.renene.2017.12.096.

Improving the energy sustainability of a Swiss village through building renovation and renewable energy integration

M. Le Guen; L. Mosca; A. T. D. Perera; S. Coccolo; N. Mohajeri et al. 

Energy and Buildings. 2018. Vol. 158, p. 906-923. DOI : 10.1016/j.enbuild.2017.10.057.

Effects of city size on the large-scale decentralised solar energy potential

N. Mohajeri; D. Assouline; A. Gudmundsson; J-L. Scartezzini 

2017. CISBAT 2017 International Conference, Lausanne, Switzerland, 6-8 September 2017. p. 697-702. DOI : 10.1016/j.egypro.2017.07.372.

Extending building integrated photovoltaics (BiPV) using distributed energy hubs. A case study in Cartigny, Switzerland

A. L. Kuehner; N. Mdeihli; S. Coccolo; A. Perera; N. Mohajeri et al. 

2017. CISBAT 2017 International Conference, Lausanne, Switzerland, 6-8 September 2017. p. 487-492. DOI : 10.1016/j.egypro.2017.07.299.

Achieving energy sustainability in future neighborhoods through building refurbishment and energy hub concept: a case study in Hemberg-Switzerland

M. Le Guen; L. Mosca; A. Perera; S. Coccolo; N. Mohajeri et al. 

2017. CISBAT 2017 International Conference, Lausanne, Switzerland, 6-8 September 2017. p. 265-270. DOI : 10.1016/j.egypro.2017.07.320.

Quantifying rooftop photovoltaic solar energy potential: A machine learning approach

D. Assouline; N. Mohajeri; J-L. Scartezzini 

Solar Energy. 2017. Vol. 141, p. 278-296. DOI : 10.1016/j.solener.2016.11.045.

3D Model for Solar Energy Potential on Buildings from Urban LiDAR Data

A. Bill; N. Mohajeri; J-L. Scartezzini 

2016. UDMV 2016 - Eurographics Workshop on Urban Data Modelling and Visualisation, Liège, Belgium, December 8, 2016.

Does roof shape matter? Solar photovoltaic (PV) integration on building roofs

N. Mohajeri; D. Assouline; B. Guiboud; J-L. Scartezzini 

2016. Zurich, June 15-17 2016; Sustainable Built Environment (SBE) regional conference, Zurich, Switzerland, June 15-17, 2016. DOI : 10.3218/3774-6_21.

How street canyon configuration control the accessibility of solar energy potential: Implication for urban design

N. Mohajeri; A. Gudmundsson; T. Kunckler; G. Upadhyay; D. Assouline et al. 

2016. PLEA - 36th International Conference on Passive and Low Energy Architecture. Cities, Buildings, People: Towards Regenerative Environments, Los Angeles, July 11-13, 2016.

Effects of urban compactness on solar energy potential

N. Mohajeri; G. Upadhyay; A. Gudmundsson; D. Assouline; J. Kämpf et al. 

Renewable Energy. 2016. Vol. 93, p. 469-482. DOI : 10.1016/j.renene.2016.02.053.

A machine learning methodology for estimating roof-top photovoltaic solar energy potential in Switzerland

D. Assouline; N. Mohajeri; J-L. Scartezzini 

2015. CISBAT 2015, EPFL, Lausanne, September 9-11th, 2015. p. 555-560. DOI : 10.5075/epfl-cisbat2015-555-560.

Expansion and densification of cities: linking urban form to ecology

N. Mohajeri; A. Gudmundsson; J-L. Scartezzini 

2015. CISBAT 2015, EPFL, Lausanne, September 9-11th, 2015. p. 475-480. DOI : 10.5075/epfl-cisbat2015-475-480.

Expansion and densification of cities: linking urban form to urban ecology

N. Mohajeri; A. Gudmundsson; J-L. Scartezzini 

2015. International Conference on Future Buildings & Districts Sustainability From Nano to Urban Scale, EPFL Lausanne Switzerland, 9 – 11 September 2015.

Neighbourhood morphology and solar irradiance in relation to urban climate

N. Mohajeri; A. Gudmundsson; G. Upadhyay; D. Assouline; J-L. Scartezzini 

2015. 9th International Conference on Urban Climate jointly with 12th Symposium on the Urban Environment, Toulouse France, 20- 24 July 2015.

How green are British cities? Scaling relations and CO2 emissions

N. Mohajeri; A. Gudmundsson; J. French; J-L. Scartezzini 

2015. AUM2015 - The 5th Symposium on Applied Urban Modelling - Green Cities, University of Cambridge - UK, 24-29 June, 2015.

Statistical-thermodynamics modelling of the built environment in relation to urban ecology

N. Mohajeri; A. Gudmundsson; J-L. Scartezzini 

Ecological Modelling. 2015. Vol. 307, p. 32-47. DOI : 10.1016/j.ecolmodel.2015.03.014.

CO2 emissions in relation to street-network configuration and city size

N. Mohajeri; A. Gudmundsson; J. R. French 

Transportation Research Part D: Transport and Environment. 2015. Vol. 35, p. 116-129. DOI : 10.1016/j.trd.2014.11.025.

Quantitative analysis of structural changes during rapid urban growth

N. Mohajeri; P. Poursistani; P. Poursistani; A. Gudmundsson 

Journal of Urban Planning and Development. 2015.  p. 05014014-1, 05014014-10. DOI : 10.1061/(ASCE)UP.1943-5444.0000213.

Analysing and modelling the growth and efficiency of urban transportation infrastructures

N. Mohajeri; A. Gudmundsson; J. L. Scartezzini 

2014. Symposium on Applied Urban Modelling - Planning Urban Infrustructure, University of Cambridge,Cambridge, UK, April 1-3. 2014.

Dike emplacement at Bardarbunga, Iceland, induces unusual stress changes, caldera deformation, and earthquakes

A. Gudmundsson; N. Lecoeur; N. Mohajeri; T. Thordarson 

Bulletin Of Volcanology. 2014. Vol. 76, num. 10, p. 869. DOI : 10.1007/s00445-014-0869-8.

Analyzing Variation in Street Patterns: Implications for Urban Planning

N. Mohajeri; A. Gudmundsson 

Journal of Architectural and Planning Research. 2014. Vol. 31, num. 2, p. 112-127.

The Evolution and Complexity of Urban Street Networks

N. Mohajeri; A. Gudmundsson 

Geographical Analysis. 2014. Vol. 46, num. 4, p. 1-23. DOI : 10.1111/gean.12061.

Quantifying the Differences in Geometry and Size Distributions of Buildings Within Cities

N. Mohajeri; A. Gudmundsson 

Nexus Network Journal: architecture and mathematics. 2014. Vol. 16, num. 2. DOI : 10.1007/s00004-014-0191-y.

Visualizing street orientation and solar radiation in relation to complex topography

N. Mohajeri; A. Gudmundsson; J. Kämpf; J-L. Scartezzini 

2014. Workshop on Urban Data Modelling and Visualisation, Strasburg, France., April 6, 2014. p. 1-6. DOI : 10.2312/udmv.20141070.

Street networks in relation to landforms: Implications for fast-growing cities

N. Mohajeri; A. Gudmundsson 

Journal of Geographical Sciences. 2014. Vol. 24, num. 2, p. 363-381. DOI : 10.1007/s11442-014-1093-3.

Entropy and order in urban street networks

A. Gudmundsson; N. Mohajeri 

Nature Scientific Reports. 2013. Vol. 3, num. 3324. DOI : 10.1038/srep03324.

Modulation of Alzheimer's pathology by cerebro-ventricular grafting of hybridoma cells expressing antibodies against Abeta in vivo

M. N. M. Gaugler; J. Tracy; K. Kuhnle; A. Crameri; R. M. Nitsch et al. 

FEBS Lett. 2005. Vol. 579, num. 3, p. 753-6. DOI : 10.1016/j.febslet.2005.01.002.