Milan-Area Traffic Service

An interactive map of Milan (see sample screen in Figure 10.5) became the basis for all location services related to the city. The map was preinstalled into the client computer, and only the data updates were made over the air while mobile. To use the service, a customer accessed the service homepage, opened a street map encompassing the whole metropolis, and could then zoom in and out by clicking on icons, or pan in all directions by clicking on the edges of the map. Panning was particularly useful while following the path that a particular street cut through the city. Character shortcuts and arrow keys were provided as alternative ways to navigate.

Location identification is a feature telling customers their present location on the basis of the mobile network cell’s identification information. A query is launched when the customer clicks on a “Where am I?” icon. Our system generated a reply in 6 seconds including date and time, geographic coordinates of the center of the cell, and an approximate radius of coverage of the cell. The map was then redrawn to indicate the user’s approximate physical location. This information was presented by displaying a circle with the given radius centered on geographic coordinates of the cell’s base station. The radius indication was seen as useful, because the radius of the cell varied from city center to peripheral areas. At the same time the date and time of the actual location was displayed in a window, as the user may have been moving. The accuracy of location identification was not precise enough for street navigation, but the approximate location helped a driver interpret traffic information presented on the interactive map.

Traffic updates were recalled from a database on the server. The database itself was continuously updated by a specialized traffic information service provider. Topical traffic conditions were transferred in a very compacted format to allow the fastest possible download time to the mobile client. A typical traffic update download was 5 kilobytes (kbytes) with a download time under 8 seconds, including map redraw time. This extremely compacted traffic data was available for about 3000 streets around the Milan area. Each street’s traffic status was indicated by a different color—green for light, yellow for medium, and red for heavy traffic. In addition, the map showed specific traffic events. By clicking related icons, users could invoke detailed text notifications to be displayed on the bottom frame of the screen. Information depth was increased with impediments such as street construction works in progress, traffic accidents, fog, and heavy rain. These downloads included about 150 characters of text about the location of the event, a short description, and the exact time of last update, and download time was no more than 3 seconds.

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Figure 10.5: Milan-area traffic service sample screens.



Mobile Usability(c) How Nokia Changed the Face of the Mobile Phone
Mobile Usability: How Nokia Changed the Face of the Mobile Phone
ISBN: 0071385142
EAN: 2147483647
Year: 2005
Pages: 142

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