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Elizabeth Brennan. Crime Reporting System. Previous Work. Created Crime Visualization System as Independent Study Imported, explore, and clean data set Created visualization with searching capabilities Performed data mining
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Elizabeth Brennan Crime Reporting System
Previous Work • Created Crime Visualization System as Independent Study • Imported, explore, and clean data set • Created visualization with searching capabilities • Performed data mining • Modification of DBScan algorithm used to identify hot spots and outliers • Use Microsoft Business Intelligence Development Studio to perform association rule mining and clustering
Goals • Create Mobile Functionality • Allow victims to report crime from cell phone • Track mobile police units • Create More Mature Visualization • Integrate with ArcGIS to incorporate spatial data analysis • Explore K-Means Clustering • Uncover relationships in the data
Related Work • Burigat and Chittaro explore queries and visualizations targeted to mobile devices • Frank, Caduff, and Wuersch create mobile devices that adapt to the user's orientation • Chen et al. use RSS to deliver information relevant to the user in terms of space and time • Helal and Elmagarmid explore the challenges of mobile computing • COPLINK is used by law enforcement professionals to track crime networks
Data Sets • XML data sets of Falls Church, Fairfax, and Arlington • Shapefiles from VEDP • Correctional Facilities, Schools, Hospitals, and Metro Stops • Web Services for Reverse Geocoding • User input data
Data Sets: Shapefiles • Download shapefiles from VEDP • Add into SQL Server using Morton Nielson tool • Forced to add as geometry type • Most conversions are bad: confirm using .AsGml() function on column • Most files contain latitude and longitude fields. These are converted into a new column with type Geography • Data compatible with ArcGIS
Simulation a Mobile Environment • Design application to run on device running the Windows Mobile 6.0 operating system
Simulating a Mobile Environment • Develop in Visual Studio 2005 using Windows Mobile 6 sdk • Use emulator image for Windows Mobile 6 Professional • Screen is 240 x 320 pixels
Simulating a Mobile Environment • ActiveSync 4.5 was used to connect the mobile device to the laptop that hosted the development environment • Data synchronization • Import and export data
Simulating a Mobile Environment • Windows Mobile 6.0 includes the FakeGPS utility • This simulates receiving GPS data • Uses NMEA files to track the position of the device • Must install FakeGPS on the mobile device • Add reference to Microsoft.WindowsMobile.Samples.Location.dll
Simulating a Mobile Environment • Want to track the phone number of the user • Save the phone number as the owner's number on the emulator device • Add reference to Microsoft.WindowsMobile.Status
Creating the Application: Reporting the Incident • Use web service to bind list of crime types • Use GPS to find the current location of the user • User clicks the report button and sends information about the type of crime, location, and phone number • Use reverse geocoding web service to find the address closest to the user's current location
Challenge Web Services • Local Web Service • Cannot reference localhost when using the device emulator • Must update the reference to the web service to use the current IP address • Third Party Web Service • May be unreliable • Reverse geocoding service stopped working
Creating the Application: Mobile Units • Represent the movement of police vehicles • Uses a web service to update its status and location • The phone number of the unit is used as a unique identifier • A drop down box indicates whether the unit is available or busy • A message is sent to the server when the user clicks the update button or the position of the unit changes
Creating the Application: Connecting Users • When the user submits an incident report, the nearest mobile unit is returned to the user • Proof of concept, would not be used in actual environment
Web Services • Create web services to communicate with the clients • Act as interface between client and database
Creating a Visualization • Original visualization provided was a map that provided searching capabilities • Want to create a more mature visualization • ArcGIS has gained popularity because it provides good visualizations with spatial analysis capabilities • Provides geoprocessing abilities like overlays and clipping • Spatial analysis features • Map making
ArcGIS Problems • Integration • Need Enterprise edition of ArcGIS to work with full featured SQL Server 2008 • Can integrate with SQL Server Express 2008 • Need edition with ArcEditor and ArcInfo which is not included in the student license • SQL Server Express has a 2GB limit • Solution • Create a view that has latitude and longitude as decimal values and no data types that are stored as binary objects • Create OLE DB connection to server and use the Display XY feature
Web Based Visualization • When it seemed that integration with ArcGIS would not be possible, other mapping solutions were explored • Google Earth • Virtual Earth
Visualization: Virtual Earth Application • Enables map development with JavaScript development model • Has interactive SDK • Can use GeoRSS and Web Services as data sources
Visualization: Virtual Earth • Attempt to create solutions with GeoRSS and web services • Involves a lot of JavaScript • Lots of time was spent and no working solution was created
Visualization: Virtual Earth • Use Microsoft Live Tools for Visual Studio 2008 • Includes Virtual Earth Map control • Moves work from JavaScript to the code behind • Smooth development • Drawbacks • If too many records are in a layer, an error will be produced during serialization • Can set the length of JSON messages but that can still be exceeded • Style sheets may interfere with rendering of map
Data Mining: K-Means • Goal: Perform clustering on the data to find patterns in the data • Limit data set to Falls Church since it a computationally intense process and resources are limited • Use different distance metrics • Use Orthodromic distance • Use Orthodromic distance, distance in days, and if the crime types are the same (0 if same, 1 otherwise) • Normalize second technique
K-Means Improvements • Most clusters converged in less than 10 iterations • Attempt to improve • Exclude farthest point(s) when creating new centroids • Pick centroid with the farthest point and randomly pick new centroid • No improvement in lowering SSE
Future Work • Include domain expert to refine data mining models and visualizations • Integrate into working network • Use user data to create preliminary police report • Include the dispatcher role • Improve user interfaces for mobile devices • Implement spatial index • Attempted but received error message that the current database server did not support its creation
Conclusions • Lots of data available but it is difficult to locate • Lots of different tools. They are easy to integrate if you choose the right tools. • Spatial data is resource intensive • Potential exists but the surrounding processes need to mature