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Researchers Interview

Yuji Yoshimura (Cofounder, laboratory urban DECODE, Spain)
March 1, 2017

Yuji Yoshimura
- Please tell us about the content of your previous and current research

My specialty is urban planning utilizing data. I am engaged in big data analyses focused on the activities of the general public, for example mobility analyses of how pedestrians move and where and how long they stay in the context of cities and architectural structures. I first become involved in this field when I starting working at Barcelona Urban Ecology Agency (BCNecologia), a government agency, approximately 10 years ago, and became deeply involved in the work of drawing up the city plan of Barcelona there. Originally my specialty was architecture, so for me data analysis of the activities of people was completely outside my field of expertise and I had to start from zero.

The pilot project of Gràcia District for converting automobile roads into pedestrian streets, called the Pedestrian Space Plan, and the research project ICING (Innovative cities for the next generation) adopted as ICT Research for Innovative Government under the EU’s Sixth Framework Programme (FP6) both entrusted Barcelona BCNecologia with the work of using new information and communications technology to develop data collection methods for mobility analyses. Around 2005 when we started ICING, in the field of traffic engineering collecting extensive data on where cars were coming from and going to and how many cars were driving on the roads was extremely difficult, so I studied every day, and worked on the project desperately hard. Fortunately, Jaume Barceló, a world authority in traffic simulations who was then a Professor at the Polytechnic University of Catalonia, assisted me in my work, and after a period of trial and error developed a sensor that could connect using the Bluetooth functions of the mobile phones that were just beginning to become widespread at that time. When we analyzed the traffic data obtained from this sensor, we realized that the activity patterns of people could be obtained with a precision incomparably better than before, and we received high praise from FP6 which concluded that the sensor would be extremely effective for indispensable city management in smart cities.

Moreover, officials from The Louvre became interested in this sensor and we ended up conducting joint research with them regarding big data analyses of how visitors move about inside the museum, the results of this research attracted the interest of new researchers, and through this series of developments my involvement in the mobility field that started from my participation in the pilot project gradually expanded into research initiatives with an academic character. My own interest also gradually shifted to the pursuit of science, and in November 2016 I received my doctorate in computer science.

- What did you feel through your participation in a research project with a social implementation perspective?

An important issue for constructing a smart city is to not only develop but also install sensors that measure the movement of people. In ICING it was decided to test install the sensors in the traffic lights inside Barcelona City, but we were also helped by the fact that there was already a cooperative relationship with Barcelona city hall in Gràcia District’s Pedestrian Space Plan and the fact that Barcelona City itself is a city open to innovation, so when we consulted with the city we were able to gain consent for the installation of the sensors in the traffic lights. I believe that it is extremely difficult to install this kind of sensor in public spaces in Japan due to legal restrictions, privacy concerns, etc. so I think the fact that Barcelona city hall provided full backup for the sensor installation was a major element in the success of the city plan pilot project in which I was involved. I become strongly aware of the fact that the understanding and environmental development of local governments is very important for testing this kind of technology in social verification projects.

Gràcia District’s Pedestrian Space Plan is already finished and roads which used to have lots of traffic have now changed to pedestrian streets lined with trees. Consequently people have gradually entered this area, and the character of the town is changing with the opening of new retail stores, cafes, etc. This plan is the pilot project of the social test called the Superblock Plan, a pedestrian space project that Barcelona is now implementing on a large scale aiming for completion by 2018. I feel joy and pride in the dynamism shown by the fact that the project that I was linked to and involved in from the start has now led to a city plan that represents the entire city.

- What kinds of challenges will you take on going forward?

Looking back on my activities to date, I think that due to the widespread adoption of mobile phones and the installation of sensors the temporal and spatial activities of people that were not quantified previously are now accumulated as a digital footprint. Looking out at the world, data related to these kinds of activities of people is now accumulated on servers due to the rapid and widespread adoption of ICT in social life. I would like to use these kinds of big data to carry out more detailed analyses of the temporal and spatial activities of people. Specifically, I would like to be able to chronologically verify how the economic activities of Gràcia District changed between before and after implementation of the Pedestrian Space Plan, and it has been decided that I will travel to the United States and start new research in the MIT SENSEable City Lab from March 2017.

So far I have been doing the pedestrian space project for approximately 10 years and one thing I thought is that it is not acceptable to carry out this pedestrian space project anywhere; rather we should decide the good places for making pedestrian spaces, and the places where this is not necessary, in accordance with the structure of the city. Structure means the distribution of shops and centrality of the city street network when viewed in terms of the city overall. For example, I intend to use analyses to show the relationship with structure consisting of how the sales of shops changed between before and after making a pedestrian space. This is the reason that I thought I would advance my research with a renewed focus on Gràcia District.

One more reason I thought that I would like to make the analyses of the spatiotemporal activities of people more detailed is that I thought that perhaps this kind of analysis could potentially have an impact on architectural design as well. Previously architects have made their designs by observing and predicting the movement of people, and my concept was that perhaps we could expect a different development if verification data was added to that approach. I basically maintained the stance of being an architect and also participated in Barcelona’s city plan project from the perspective of a specialist in architecture. Currently I am thinking that it would be good if I could gain the advantage of being a data scientist of the city so to speak, and in the future give feedback on the outcomes obtained from my activities in the mobility field to the city plan and architecture and be involved in town planning from a new perspective.