John K.S. Lau & C.K. Tham & T. LuoE-mail: {elelksj, eletck, eleluo}@nus.edu.sg

Participatory Cyber Physical System in Public Transport

ApplicationIEEE/ACM UCC’11 International Workshop of Cloud Computing and Scientific Applications (CCSA 2011)

Participatory Cyber Physical System in Public Transport ApplicationJKS Lau, CK Tham, T Luo 2

Motivation

•How to enrich travel experience thereby increase public transport ridership?• How to obtain data if transit agencies are either incapable or reluctant?

Participatory Cyber Physical System in Public Transport ApplicationJKS Lau, CK Tham, T Luo 3

Contributions

•ContriSenseCloud–Participatory cyber physical system.

•ContriSense:Bus–Application on ContriSenseCloud.–Application on Android smartphones.

•RESTful API–Data as a service.

•NTRS and S2B algorithms–Complements GPS trajectory database and MATE

algorithm.

Participatory Cyber Physical System in Public Transport ApplicationJKS Lau, CK Tham, T Luo 4

ContriSenseCloud Architecture

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ContriSense:Bus Architecture

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Cyber Physical Society

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RESTful API

http://example.com/xchange/api/view/1

http://example.com/xchange/api/view/1/5

http://example.com/xchange/api/view/1/5/2

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NTRS and S2B Algorithms

NTRS

GPS Trajectory Database

MATE

S2B

Real World

Us

RESTful

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User-contributed Traces

LegendBalloon – Bus stop (node)Red line – Actual Green line – Mapped

NUS D1/D2 95

190 196

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Services in ContriSense:Bus

XML

JSON

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Performance MeasurementsLa

tenc

y (s

)

No. of travel time queried

Late

ncy

(s)

No. of concurrent users (queries)

No. of concurrent users (API calls)

Late

ncy

(s)

Late

ncy

(s)

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Future Works

• Integrating closed-loop incentive scheme for supply and demand valuation.• Improving S2B algorithm so that Kmax and Kmin are adaptive.• Introducing load balancing for higher scalability.

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THANK YOUQuestions?