Dr. Lauren GardnerAssociate Professor

Civil Engineering at Johns Hopkins University Co-Director, Center for Systems Science and Engineering

Member, Research Centre for Integrated Transport Innovation (rCITI) at UNSW SydneyVisiting Scientist, CSIRO (Australia)

Network Modeling of Transport Systems

Center for Systems Science and Engineering

Pricing for Transport Networks• Model Road Pricing Schemes

• Consider Uncertainty/Information• Compare Policy Options• Quantify System Performance

Planning for Alternative Vehicle Technologies• Integration of Power and Transport Systems

• User Behaviour• Sustainability Metrics• Policy Development• Multi-Objective Network Design

Mobility and Epidemiology• Role of Transportation in Disease Spread

• Quantification of Disease Spreading Risk• Predicting Outbreak Behaviour Patterns• Optimizing Intervention Strategies

Research Areas of Focus

Overview of Research Methods

Objective: Exploit available information to infer and predict local and global patterns of contagion, quantify the risk posed (e.g., by components of transport systems) in the spread of disease, and design optimal mitigation strategies

Methods:i. Mathematical modeling ii. Network theoryiii. Optimizationiv. Simulationv. Statistics

Contributions:i. Policy evaluation and decision supportii. Optimize resource allocation

Hypothesis: The movement of people, pathogens and vectors (e.g., mosquitos) plays an integral role in the risk of disease.

Case Geo-location Data Environmental, Land-use and Climate

Large-scale Data Requirements

Local Mobility Global Transport Networks

Social Media, Cell phone, Credit Card, Google, etc

Social-Contact Network Models

Can we use available spatiotemporal infection data (and other information) to better understand the risk posed by an outbreak?

Modeling Public Transit Contact PatternsLocal Mobility Patterns

“Flu on the Bus” ProblemDefine Contact Networks

High Risk Transit Trips

Bota, et al. (2017), Netw Spat Econ.

Apply network-based statistics, algorithms and simulation

Extract ridership data

Vehicle trip network• Nodes ← vehicle trips loads• Links ← transfer passenger volumes

Public Transit Network AnalysisContact network. Large circles represent vehicle-trips

Fig. Vehicle-trip network

Vehicle Trip Network:• 8002 nodes (vs 94,475)• 263,792 links (vs 6,287,847)

Planning for New Vehicles Technologies

Research Questions:1. How will infrastructure and planning decisions change due to the presence of new

vehicle technologies? e.g., Electricity Pricing, EV charging Station location, Transport System Design Objectives (safety, emissions, etc)

2. How does the behaviour of drivers change in the presence of these new technologies?

Research Applications:Integration - Convergence of transport/power systemsPlanning - Demand-Supply for electric power gridUser Behaviour – Range Anxiety, RoutingSustainability - Upstream emissionsPolicy Decisions - Charging Infrastructure Location Network Design Problem – Multiple objectives

Modeling Sustainable Transport Systems:

ELECTRIC VEHICLES

•improve battery storage•power train configuration

Transportation:

•encourage clean sources•reduce fossil fuel dependence

•standards•incentives

•affordability•business models•financing

•consumers•travellers•range anxiety•education

•network modelling•distance limitations•destination choices, route choice•infrastructure improvement Electric Power Systems:

Economic:

Policy:

Energy:

Technology:

Behavioural:

•Smart Grid•effective management•charging infrastructure•mobile storage devices

Modeling the System Impact of Travel Demand Variability on Emissions and Congestion

★ The expected performance of a system may not be correlated to the variability of the system

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These are the the same design scenario and so on

Modelling Spatiotemporal EV Uptake and Energy Consumption Rates

Relative likelihoods that households in each CCD

would purchase an electric vehicle.

AECOM Vehicle Sales Forecast for

Sydney GMA

Average daily distance driven by a vehicle owner

residing in each CCD.+ +

Thank You

Email: l.gardner@jhu.eduOffice: Latrobe 104

Center for Systems Science and Engineering