Kota Tsubouchi

Dr. Kota Tsubouchi


Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 April 2024 in Scientific Data
Verified
Journal Article
Open access
PDF file
TYTakahiro Yabe
Takahiro Yabe
KTKota Tsubouchi
Kota Tsubouchi
TSToru Shimizu
Toru Shimizu
YSYoshihide Sekimoto
Yoshihide Sekimoto
KSKaoru Sezaki
Kaoru Sezaki
APAlex Pentland
Alex Pentland
Modeling and predicting human mobility trajectories in urban areas is an essential task for various applications including transportation modeling, disaster management, and urban planning. The recent availability of large-scale human movement data collected from mobile devices has enabled the development of complex human mobility prediction models. However, human mobility prediction methods are often trained and tested on different datasets, due to the lack of open-source large-scale human mobility datasets amid privacy concerns, posing a challenge towards conducting transparent performance comparisons between methods. To this end, we created an open-source, anonymized, metropolitan scale, and longitudinal (75 days) dataset of 100,000 individuals’ human mobility trajectories, using mobile phone location data provided by Yahoo Japan Corporation (currently renamed to LY Corporation), named . The location pings are spatially and temporally discretized, and the metropolitan area is undisclosed to protect users’ privacy. The 90-day period is composed of 75 days of business-as-usual and 15 days during an emergency, to test human mobility predictability during both normal and anomalous situations.

20 February 2019 in PLOS ONE
Verified
Journal Article
Open access
PDF file
TYTakahiro Yabe
Takahiro Yabe
YSYoshihide Sekimoto
Yoshihide Sekimoto
KTKota Tsubouchi
Kota Tsubouchi
SISatoshi Ikemoto
Satoshi Ikemoto
Despite the importance of predicting evacuation mobility dynamics after large scale disasters for effective first response and disaster relief, our general understanding of evacuation behavior remains limited because of the lack of empirical evidence on the evacuation movement of individuals across multiple disaster instances. Here we investigate the GPS trajectories of a total of more than 1 million anonymized mobile phone users whose positions were tracked for a period of 2 months before and after four of the major earthquakes that occurred in Japan. Through a cross comparative analysis between the four disaster instances, we find that in contrast to the assumed complexity of evacuation decision making mechanisms in crisis situations, an individual’s evacuation probability is strongly dependent on the seismic intensity that they experience. In fact, we show that the evacuation probabilities in all earthquakes collapse into a similar pattern, with a critical threshold at around seismic intensity 5.5. This indicates that despite the diversity in the earthquakes profiles and urban characteristics, evacuation behavior is similarly dependent on seismic intensity. Moreover, we found that probability density functions of the distances that individuals evacuate are not dependent on seismic intensities that individuals experience. These insights from empirical analysis on evacuation from multiple earthquake instances using large scale mobility data contributes to a deeper understanding of how people react to earthquakes, and can potentially assist decision makers to simulate and predict the number of evacuees in urban areas with little computational time and cost. This can be achieved by utilizing only the information on population density distribution and seismic intensity distribution, which can be observed instantaneously after the shock.

3 May 2021 in IEEE Transactions on Knowledge and Data Engineering
Verified
Journal Article
Closed access
RJRenhe Jiang
Renhe Jiang
ZCZekun Cai
Zekun Cai
ZWZhaonan Wang
Zhaonan Wang
CYChuang Yang
Chuang Yang
ZFZipei Fan
Zipei Fan
RSRyosuke Shibasaki
Ryosuke Shibasaki
Predicting the density and flow of the crowd or traffic at a citywide level becomes possible by using the big data and cutting-edge AI technologies. It has been a very significant research topic with high social impact, which can be widely applied to emergency management, traffic regulation, and urban planning. In particular, by meshing a large urban area to a number of fine-grained mesh-grids, citywide crowd and traffic information in a continuous time period can be represented with 4D tensor (Timestep, Height, Width, Channel). Based on this idea, a series of methods have been proposed to address grid-based prediction for citywide crowd and traffic. In this study, we revisit the density and in-out flow prediction problem and publish a new aggregated human mobility dataset generated from a real-world smartphone application. Comparing with the existing ones, our dataset holds several advantages including large mesh-grid number, fine-grained mesh size, and high user sample. Towards this large-scale crowd dataset, we propose a novel deep learning model called DeepCrowd by designing pyramid architectures and high-dimensional attention mechanism based on Convolutional LSTM. Lastly, thorough and comprehensive performance evaluations are conducted to demonstrate the superiority of the proposed DeepCrowd comparing to multiple state-of-the-art methods.

19 December 2023 in Expert Systems with Applications
Verified
Journal Article
Open access
KUKentaro Ueda
Kentaro Ueda
HSHirohiko Suwa
Hirohiko Suwa
MYMasaki Yamada
Masaki Yamada
YOYuki Ogawa
Yuki Ogawa
EUEiichi Umehara
Eiichi Umehara
KYKeiichi Yasumoto
Keiichi Yasumoto

12 September 2016
Verified
Conference Paper
Open access
PDF file
TKTatsuya Konishi
Tatsuya Konishi
MMMikiya Maruyama
Mikiya Maruyama
KTKota Tsubouchi
Kota Tsubouchi
MSMasamichi Shimosaka
Masamichi Shimosaka
Thanks to the recent popularity of GPS-enabled mobile phones, modeling people flow or population dynamics is attracting a great deal of attention. Advances in methods where regular population patterns with respect to factors such as holidays or weekdays are extracted have provided successful results in irregularity detection. With large-scale crowded events such as fireworks, it is crucial that there be enough time to take countermeasures against the irregular congestion, i.e., irregularity prediction. It remains a tough challenge to predict population from GPS trace logs with existing methods. To tackle this problem, we focus here on route search logs, since aggregation of the location-oriented queries of individual plans serves as a mirror of short-term city-scale events, in contrast to GPS mobility logs. This paper presents a brand new framework for city-scale event prediction: CityProphet. By our observation of data where the route search logs related to a future event are in most cases repeatable and accumulated in proportion as the event draws near, we are able to leverage the divergence between the above two properties to predict city-scale irregular events. We demonstrate through experiments using the transit app logs of over 370 million queries that our approach can successfully predict city-scale crowded events one week in advance.

1 October 2018 in Pervasive and Mobile Computing
Verified
Journal Article
Closed access
TOTadashi Okoshi
Tadashi Okoshi
KTKota Tsubouchi
Kota Tsubouchi
HTHideyuki Tokuda
Hideyuki Tokuda