Quantifying the sensing power of vehicle fleets

Copyright © 2019 the Author(s). Published by PNAS..

Sensors can measure air quality, traffic congestion, and other aspects of urban environments. The fine-grained diagnostic information they provide could help urban managers to monitor a city's health. Recently, a "drive-by" paradigm has been proposed in which sensors are deployed on third-party vehicles, enabling wide coverage at low cost. Research on drive-by sensing has mostly focused on sensor engineering, but a key question remains unexplored: How many vehicles would be required to adequately scan a city? Here, we address this question by analyzing the sensing power of a taxi fleet. Taxis, being numerous in cities, are natural hosts for the sensors. Using a ball-in-bin model in tandem with a simple model of taxi movements, we analytically determine the fraction of a city's street network sensed by a fleet of taxis during a day. Our results agree with taxi data obtained from nine major cities and reveal that a remarkably small number of taxis can scan a large number of streets. This finding appears to be universal, indicating its applicability to cities beyond those analyzed here. Moreover, because taxis' motion combines randomness and regularity (passengers' destinations being random, but the routes to them being deterministic), the spreading properties of taxi fleets are unusual; in stark contrast to random walks, the stationary densities of our taxi model obey Zipf's law, consistent with empirical taxi data. Our results have direct utility for town councilors, smart-city designers, and other urban decision makers.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:116

Enthalten in:

Proceedings of the National Academy of Sciences of the United States of America - 116(2019), 26 vom: 25. Juni, Seite 12752-12757

Sprache:

Englisch

Beteiligte Personen:

O'Keeffe, Kevin P [VerfasserIn]
Anjomshoaa, Amin [VerfasserIn]
Strogatz, Steven H [VerfasserIn]
Santi, Paolo [VerfasserIn]
Ratti, Carlo [VerfasserIn]

Links:

Volltext

Themen:

Air Pollutants
City science
Evaluation Study
Journal Article
Mobile sensing
Research Support, U.S. Gov't, Non-P.H.S.
Urban monitoring
Urban sustainability

Anmerkungen:

Date Completed 26.03.2020

Date Revised 26.03.2020

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1073/pnas.1821667116

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM298033526