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A Google-Map-Based Arterial Traffic Information (GATI) System

Authors: Yao-Jan Wu

Dr. Yinhai Wang

Dr. Dalin Qian

Date: 10/03/2007

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Outline

Introduction System Architecture Database Design Implementation Conclusion and Future work

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Introduction System Architecture Database Design Implementation Conclusion and Future work

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Web Based Traffic Information System

• Washington State Department of Transportation– Puget Sound Traffic Flow Map

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Google-based Traffic Information System

• Seymour, E.J. Miller, B.(2007). Google-Based Mapping System for Traffic Management Center Web Navigation, TRB – http://daltrans.org/

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 Arterial Traffic Information System

• Bellevue Real-Time Traffic Map – Not in right scale– Less interactive– Research?

Source: http://www.ci.bellevue.wa.us/

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Introduction System Architecture Database Design Implementation Conclusion and Future work

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System Architecture

HTTPWeb Brower

Web Brower

Web Brower

Apache Web ServerMySQL Server

HTTP

HTTP

Data Server in the City of Bellevue

FTP

Client Side

Javascript

XHTML

CSS

XML

Server Side

PHP

STAR Lab

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Introduction System Architecture Database Design

Traffic Data from the City of Bellevue Pre-process

Implementation Conclusion and Future work

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Traffic Data from the City of Bellevue

• The city of Bellevue [Liang, 2006]

– 177 signalized intersections– More than 840 advance detector– Around 465 links (varied).

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Pre-process

• Locate all intersections (nodes)

• Build up link-intersection relation table

• Import Data into Database– Link Data– Intersection Data– Traffic Data

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Traffic Data

• All link data– One minute update file (with all the links for

the flow map)– Filename name: 0607121314.csv

Link #

Link ID

Smooth Volume

Smooth Occupancy

Cycle length

Plan # running

Color code

Incident code

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All link data

• Link description– Fxxxddmn (e.g. F001EBT1)– xxx= Intersection #– dd= Direction (EB, WB, NB, SB)– m= Movement: (L)eft, (T)hru, (R)ight – n= # of lanes

Link #

Link ID

Smooth Volume

Smooth Occupancy

Cycle length

Plan # running

Color code

Incident code

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All link data

Date

Weekday

Time

Link ID

Link Description

volume

Occupancy

Volume+K

Cycle length

Plan#

Color code

• Color code [Liang, 2006]– 1,2=green (light)– 3=yellow (Moderate)– 4=red (Heavy)– 5=black (Severe)– 0=gray (No data)

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Locate all intersections

• Saving Data with GXmlHttp (Ajax!)

• Do it manually with reference to the Map of Signalized Intersection

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All Intersections

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Build up link-intersection relation table

• Do it manually with reference to the Map of Signalized Intersection

Link #

Link ID

Smooth Volume

Smooth Occupancy

Cycle length

Plan # running

Color code

Incident code

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Database

• Three tables have to be built in MySQL database– Traffic data table– Link Data table– Link_Intersection table

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Relationships among tables

Link&Intersection Relationship Table (Link_Intersection)

Traffic Data Table (all_link_jan07)

Join(2)

Join (1)

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Introduction System Architecture Database Design Implementation Conclusion and Future work

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Interface

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User Interface (Browsers)

System Server (STAR Lab)

FTP Data Server (City of Bellevue)

FTP Downloader (written by C#)

Javascript Interpreter/ AjaxGoogle MapsEngine

MySQLDatabase

XML files

XML files

XML files

PHP Interpreter

FTPXML filesXML filesReal-time traffic data (CSV file)

Display User Input

Flowchart

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FTP Downloader

• Functions– Data Downloading– Generate real-time

XML data– Update database– Archive data feeds

User Interface (Browsers)

System Server (STAR Lab)

FTP Data Server (City of Bellevue)

FTP Downloader (written by C#)

Javascript Interpreter/ AjaxGoogle MapsEngine

MySQLDatabase

XML files

XML files

XML files

PHP Interpreter

FTPXML filesXML filesReal-time traffic data (CSV file)

Display User Input

HTTPWeb Brower

Web Brower

Web Brower

Apache Web ServerMySQL Server

HTTP

HTTP

Data Server in the City of Bellevue

FTP

Client Side

Javascript

XHTML

CSS

XML

Server Side

PHP

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Traffic Flow Map

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Conclusion and Future Work

• Conclusion– Low cost (MySQL, Apache server, PHP, etc)– Easy to implement

• Future work– More traffic information can be shown– Analytical tools

• Versatile Query Real-time evaluation (Arterial, network) functions

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More Info

• STAR Lab (http://www.uwstarlab.org/)

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2008 TRB Annual Meeting Washington D.C.

• GATI Ver.2Scatter Plot Analysis Tool

Time-Domain Analysis Tool

Main Interface

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Questions?

yaojan@u.wasington.edu