Inflow process of pedestrians to a confined space

To better design safe and comfortable urban spaces, understanding the nature of human crowd movement is important. However, precise interactions among pedestrians are difficult to measure in the presence of their complex decision-making processes and many related factors. While extensive studies on pedestrian flow through bottlenecks and corridors have been conducted, the dominant mode of interaction in these scenarios may not be relevant in different scenarios. Here, we attempt to decipher the factors that affect human reactions to other individuals from a different perspective. We conducted experiments employing the inflow process in which pedestrians successively enter a confined area (like an elevator) and look for a temporary position. In this process, pedestrians have a wider range of options regarding their motion than in the classical scenarios; therefore, other factors might become relevant. The preference of location is visualized by pedestrian density profiles obtained from recorded pedestrian trajectories. Non-trivial patterns of space acquisition, e.g., an apparent preference for positions near corners, were observed. This indicates the relevance of psychological and anticipative factors beyond the private sphere, which have not been deeply discussed so far in the literature on pedestrian dynamics. From the results, four major factors, which we call flow avoidance, distance cost, angle cost, and boundary preference, were suggested. We confirmed that a description of decision-making based on these factors can give a rise to realistic preference patterns, using a simple mathematical model. Our findings provide new perspectives and a baseline for considering the optimization of design and safety in crowded public areas and public transport carriers.Comment: 23 pages, 6 figure

人の集団に関する新たな評価方法の考察2

九州大学応用力学研究所研究集会報告 No.21ME-S7 「非線形波動研究の現状と将来 : 次の10 年への展望」RIAM Symposium No.21ME-S7 Current and Future Research on Nonlinear Waves : Perspectives for the Next Decade筆者らはこれまでに決定論的な資産価格評価法(正味現在価値)を応用して人の混雑に関する価値評価理論を構築することに成功している。本研究では、この決定論的な理論をリアルオプションアプローチと呼ばれる手法を用いて確率的な変動を考慮した理論として定式化することを目標とする。また、これらの解の評価、応用可能な混雑の事例、今後の展望についても述べたい

人の集団に関する新たな評価方法の考察

九州大学応用力学研究所研究集会報告 No.20ME-S7 「非線形波動の数理と物理」RIAM Symposium No.20ME-S7 Mathematics and Physics in Nonlinear waves本研究では、金融工学の手法を用いて人の混雑を評価する理論の構築を試みた。我々は、人の混雑を表すダイナミクスは確率項を含むLogistic 方程式に従うと仮定し、この動きを正味現在価値やリアルオプション法によって評価した。また、金融工学では、割引率を用いることによってタイミングによる価値の違いが表現されるが今回のモデルでは、割引率を人の効用を割り引くために導入し、実データに基づく推定・考察もあわせて行った

Introduction of Frictional and Turning Function for Pedestrian Outflow with an Obstacle

In this paper, two important factors which affect the pedestrian outflow at a bottleneck significantly are studied in detail to analyze the effect of an obstacle set up in front of an exit. One is a conflict at an exit when pedestrians evacuate from a room. We use floor field model for simulating such behavior, which is a well-studied pedestrian model using cellular automata. The conflicts have been taken into account by the friction parameter. However, the friction parameter so far is a constant and does not depend on the number of the pedestrians conflicting at the same time. Thus, we have improved the friction parameter by the frictional function, which is a function of the number of the pedestrians involved in the conflict. Second, we have newly introduced the cost of turning of pedestrians at the exit. Since pedestrians have inertia, their walking speeds decrease when they turn, and the pedestrian outflow decreases. The validity of the extended model, which includes the frictional function and the turning function, is verified by both a mean field theory and experiments. In our experiments, the pedestrian flow increases when we put an obstacle in front of an exit. The analytical results clearly explains the mechanism of the effect of the obstacle, i.e., the obstacle blocks pedestrians moving to the exit and decreases the average number of pedestrians involved in the conflict. We have also found that an obstacle works more effectively when we shift it from the center since pedestrians go through the exit with less turning

Simulation of space acquisition process of pedestrians using Proxemic Floor Field Model

We propose the Proxemic Floor Field Model as an extension of the Floor Field Model, which is one of the successful models describing the pedestrian dynamics. Proxemic Floor Field is the Floor Field which corresponds to the effect of repulsion force between others. By introducing the Proxemic Floor Field and threshold, we investigate the process that pedestrians enter a certain area. The results of simulations are evaluated by simple approximate analyses and newly introduced indices. The difference in pedestrian behavior due to the disposition of the entrance is also confirmed, namely, the entrance in the corner of the area leads to the long entrance time because of the obstruction by pedestrians settling on the boundary cells

複数窓口の待ち行列における待ち時間と追い越しの頻度の研究

九州大学応用力学研究所研究集会報告 No.20ME-S7 「非線形波動の数理と物理」RIAM Symposium No.20ME-S7 Mathematics and Physics in Nonlinear waves本研究では，待ち行列理論に歩行距離の効果を導入し，複数窓口の待ち行列に並んでいる人の平均待ち時間と追い越しの頻度について理論解析とシミュレーションを行った．そして，平均待ち時間を小さくすることができる待ち行列システムの設計法を考案した

「待ち行列の長さ＝待ち人数」でよいのか？

九州大学応用力学研究所研究集会報告 No.21ME-S7 「非線形波動研究の現状と将来 : 次の10 年への展望」RIAM Symposium No.21ME-S7 Current and Future Research on Nonlinear Waves : Perspectives for the Next Decade待ち行列理論では、待ち行列の長さは待ち人数で表される。しかし、実際の待ち行列では人が列を詰める時間のために、待ち行列の長さは待ち人数に一人当たりにスペースを乗じたものよりも長くなると考えられる。本研究では、待ち行列理論に排除体積効果を導入し、待ち行列の長さが待ち人数と異なることを示すと同時に、実験によりその現象を確認した

Real option valuation of social systems

JSTさきがけ研究集会　環境問題における数理の可能性. 平成20年6月11日～平成20年6月13日. 札幌