CITADYNE is a group of researchers interested in all topics on cities, world dynamics, complex systems, scientific methods, and visualizations.

We are at the University of Lausanne in the Institute of Geography and Sustainability.

The group is coordinated by Prof. Celine Rozenblat



Dr Jingyan Yu received the FGSE early career postdoctoral fellowship in geosciences and environment for 2 years. She is interested in complex urban systems, urban modeling, analytics, and computation.

Her research project Global Sustainable Urban Spatial Development: Past Processes, Current Development, and Future Directions aims to conduct the first study of global sustainable urban spatial development, that quantitatively analyses multi-level urban spatial development and its driving forces worldwide. It seeks to classify the global urban spatial development with a novel data-driven simulation approach and to map the global urban spatial development’s sustainability impacts. The generated knowledge will be applied to Switzerland, assessing the sustainable urban spatial development of the country and projecting future scenarios for evidence-based monitoring and policymaking.

Corneille Rogromel began his university studies at the University of N’Djamena (Chad) in the Department of Geography where he obtained his Bachelor’s degree in General Geography. Then, he continued with a Master’s degree at the University of Dschang (Cameroon), specializing in Territory-Development-Environment. After his studies, he taught 3 years of “Environmental and Social Impact Assessment” at the private university “Emi Koussi” in N’Djamena.

He is at IGD for 3 years under the confederation’s scholarships. His thesis focuses on the networks of multinational companies and African cities in the hierarchy of global cities, continental and national urban systems, and the potential for their development.

Jorge Salgado M. is an economist who graduated with honors from the Pontifical Catholic University of Ecuador and holds a Master’s degree in Economics from the University of Barcelona. He was a professor at the Faculty of Economics of the Pontifical Catholic University of Ecuador, where he taught economic theory, econometrics and regional economics. He was the coordinator of the Socio-Environmental Policy Observatory of the Faculty of Economics of the Pontifical Catholic University of Ecuador.

His research has focused on the economics of natural disasters and the development of theoretical and empirical mathematical models. He has started a PhD for 5 years in IGD in 2023 on the modeling of Urban systems in the face of climate change.

Haokun Liu received training in Geography and GIScience in China and Switzerland. Subsequently, he started his PhD in August 2023 at IGD, UNIL. His research concentrates on recognizing urban health from the complexity perspective, which focuses on the interactions inside and among cities, urban complexity, and human health. Aiming at the relevant research gaps, he expects to utilize complex networks and spatial data science to offer innovative insights.

Yubin OU has joined IGD from Sun Yat-Sen Univ. in Guangzhou for 1 year.

His research focuses on the sports dimension of the world city network, especially concentrated on the world city network based on the Olympic Games since 1984. Aiming to uncover the distinct geographical pattern, network structure, and formation mechanism of those sports events-based world city networks dominated by multiple sports-related actors, his studies may use social network analysis methods, community detection, and ERGM approach to figure out the spatial-temporal evolution patterns of different sub-network based on diverse Olympic games, as well as reflecting the evolution dynamics of those city networks. 


Dr. Mehdi BIDA defended his Ph.D. in 2022 Modelling the Transitions of Urban Systems: the Two Main US Economic Transitions.

He used economic and geographic evolutionary theories to develop a theoretical framework and apply it to investigate the evolution of the economic and geographical organization of the US system of cities over the last two centuries. The goal will be to develop agent-based models following the theoretical framework to understand how the economy of the US system of cities transitioned through its two main transitions: the first being its urbanization and its industrialization, and the second being its transition to the knowledge economy.


defended his Ph.D. thesis in 2023 on The role of cities in the transition to the Electric Vehicle: a coevolutionary approach.

This thesis considers the transition to electric vehicles (EVs) as a co-evolutionary process, looking at the invention and production of EV-related technologies in large urban regions. This research provides evidence for understanding how geographic proximity and local networks can foster the emergence of complementarities between the automotive, battery, and smart grid sectors during transitions. Using data on patents and multinational property networks, this research examines how coevolution between different technologies is related to the emergence of EV-related inventive and productive activities in urban areas

Dr. Mikhail ROGOV

defended his Ph.D. in 2021 in the CITADYNE group, on Urban resilience: towards a multi-level approach to Russian metropolitan areas facing the economic crisis 2014-2016.

Based on the evolutionary theory of urban systems, the thesis argues that cities’ resilience is shaped by the synchronicities of different processes on three urban levels: macro focuses on inter-urban flows creating a system of cities; micro focuses on the behavior of individual and collective urban actors; and meso, considering a city as an integrated system between micro and macro. Every level of urban processes has a different adaptation path following diverse shocks, and we argue that synchronicities of these multilevel adaptive dynamics create urban resilience (Rogov, Rozenblat, 2020).
Considering the economic shocks of 2014 of a top-down nature, the thesis starts with the construction of inter-urban networks of multinational firms. Using the ORBIS-BvD database on the 3,000 largest corporate networks, the inter-urban linkages were constructed. The firms, both headquarters and subsidiaries, were located in the delimited Large Urban Regions (LUR), encompassing over 80% of all the firms located in Russia. Using the datasets for 2010, 2013, 2016, and 2019 we wondered how the relative position of Russian cities in the global economic networks changed before, during, and after the economic crisis of 2014-2016.

Dr. Meiqi JIAO

She was for an internship in the CITADYNE group in 2020-2021 during her Ph.D. Her researches focus on the role of territories and networks in innovation processes. She is now Prof. Assistant in Shanghai.

Qi ZHANG earned a bachelor’s in Geography information system (GIS)  at Lu Dong University, a master’s in human geography (tourism Transport geography) at Central China Normal University and she defended her Ph.D. in Sun Yat-Sen University (Guangzhou) in 2023 on the Evolution of International Air network in Chinese cities from the perspective of a multi-layer airline. She is now a post-doc at Sun Yat-Sen University (Guangzhou).

Dr. Xiande LI

He was for an internship in the CITADYNE group in 2019-2020 for a Post-Doc. He is now an assistant professor at the Normal University of Shanghai. His researches cover Economic urban geography with a wide variety of topics.