Showing posts with label gazateer. Show all posts
Showing posts with label gazateer. Show all posts

Sunday, 16 October 2016

Integrating User-contributed Geospatial Data with assistive Geotechnology Using a localized Gazetteer

Rice, M.T.,  Hammill, W.C., Aburizaiza, A.O., Schwarz, S., and Jacobson,R.D. (2011) Integrating User-contributed Geospatial Data with assistive Geotechnology Using a localized Gazetteer, Advances in Cartography and GIScience. Volume 1, 279-291.


We present a methodology for using cartographic-based processes to alert the vision-impaired as they navigate through areas with transitory hazards. The focus of this methodology is the use of gazetteer-based georeferencing to integrate existing local cartographic resources with user-contributed geospatial data. User-contributed geospatial data is of high interest because it leverages local geographic expertise and offers significant advantages in dealing with hazard information in real-time. For blind and vision-impaired people, information about transitory hazards encountered while navigating through a public environment can be contributed by end-users in the same public environment, and quickly integrated into existing cartographic resources. For this project, we build collections of user-contributed geospatial updates from email, voice communication, text messages, and social networks. Other necessary technologies for this project include text-to-voice software, global positioning devices, and the wireless Internet. The methodology described in this paper can deliver usable, cautionary reports of hazards, obstacles, or other time-variable concerns along a pedestrian network. Using the George Mason University campus as a study area, this paper describes how transitory events can be presented in usable form to a vision-impaired pedestrian within a usably short period of time after the event is reported. Buildings and other destinations of interest can be registered in a robust, eXtensible Markup Language (XML)-based, localized gazetteer. Walking networks, parking lots, roads, and landmarks are mapped as vector-based digital information. Any events or changes to the base map, whether planned and disseminated through official channels or reported by end-users, can be linked to a location in the network as established by the attributes cataloged in the localized gazetteer, and presented on an existing base map or in an assistive technology environment. For mobile applications, a vision-impaired pedestrian with a Geographic Information System (GIS) and a Global Positioning System (GPS)-enabled assistive device can receive an alert or warning about proximity to reported obstacles. This warning might include other information, such as alternative paths and relative directions to proceed, also referenced through the localized gazetteer. This research provides insight into challenges associated with integrating user-contributed geospatial in-formation into a comprehensive system for use by the blind or vision-impaired.


Tuesday, 21 May 2013

Supporting Accessibility for Blind and Vision-impaired People With a Localized Gazetteer and Open Source Geotechnology

Rice, M.T., Aburizaiza, A.O, Jacobson,R.D, Shore , B.M., and Paez. F I.  (2012). Supporting Accessibility for Blind and Vision-impaired People With a Localized Gazetteer and Open Source Geotechnology. Transactions in GIS 16 (2):177-190.
Disabled people, especially the blind and vision-impaired, are challenged by many transitory hazards in urban environments such as construction barricades, temporary fencing across walkways, and obstacles along curbs. These hazards present a problem for navigation, because they typically appear in an unplanned manner and are seldom included in databases used for accessibility mapping. Tactile maps are a traditional tool used by blind and vision-impaired people for navigation through urban environments, but such maps are not automatically updated with transitory hazards. As an alternative approach to static content on tactile maps, we use volunteered geographic information (VGI) and an Open Source system to provide
updates of local infrastructure. These VGI updates, contributed via voice, text message, and e-mail, use geographic descriptions containing place names to describe changes to the local environment. After they have been contributed and stored in a database, we georeference VGI updates with a detailed gazetteer of local place names including buildings, administrative offices, landmarks, roadways, and dormitories. We publish maps and alerts showing transitory hazards, including location-based alerts delivered to mobile devices. Our system is built with several technologies including PHP, JavaScript, AJAX, Google Maps API, PostgreSQL, an Open Source database, and PostGIS, the PostgreSQL’s spatial extension. This article provides insight into the integration of user-contributed geospatial information into a comprehensive system for use by the blind and vision-impaired, focusing on currently developed methods for geoparsing and georeferencing using a gazetteer.