IT Roadmap to a Geospatial Future (2003) / Chapter Skim
Currently Skimming:
2. Location-Aware Computing
2. Location-Aware Computing
Pages 25-46
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 25... ...
Location sensing could be used in coastal areas, for instance, to pinpoint relevant information on meteorological and wave conditions for commercial fishermen, shipboard researchers, or recreational boaters. Other examples include the delivery of location-specific information, such as notifications of traffic congestion, warnings of severe weather conditions, announcements of nearby educa25
|
From page 26... ...
This chapter explores the current state of research and key future challenges in these areas. Because the committee's resources were limited, the discussion of current technologies focuses on the rapidly growing areas of data acquisition and delivery, which are being fueled by advances in location and orientation sensing, wireless communication, and mobile computing.
|
From page 27... ...
Using fixed, active beacons and carefully placed, passive ultrasonic sensors, they show how to calculate compass orientation to within a few degrees, using precise, subcentimeter differences in distance estimates from a beacon to each sensor on the compass. Their algorithm includes analysis of signal arrival times to produce a robust estimate of the device's orientation.
|
From page 30... ...
Infrared wireless communication is adversely affected by high levels of ambient light, such as prevail outdoors during daylight hours. Although it is difficult to foresee what new wireless technologies will emerge in the future, it is clear that advances will be constrained by tradeoffs among four factors: frequency, bandwidth, range, and density of wired infrastructure (Rappaport, 1996; CSTB, 1997~.
|
From page 31... ...
Although less widespread, wearable computers are beginning to make an impact in specialized applications. Where progress has been slow is in the integration of mobile hardware into systems that seamlessly bridge a user's desktop, his or her activities while mobile, and the Internet computing world.
|
From page 32... ...
The limited commercial deployment of mobile computing systems restricts options available to scientists for experimentation. RESEARCH CHALLENGES This section outlines the key research challenges in location-aware computing that were raised at the committee's workshop.
|
From page 33... ...
Premature standardization can result in a technically inferior standard because adequate experience and research results are not available at the point of definition. On the other hand, excessive delay can lead to a proliferation of commercial implementations and may deter eventual convergence.
|
From page 34... ...
For example, rather than having a human engineer sample signal strengths, it might be possible to program a robot to construct a signal strength map. To further speed the process, multiple mobile robots might exploit parallelism.
|
From page 35... ...
The key sensing capability (in this case, antilock brakes) is of value in and of itself, but adding locational and wireless communication capabilities amplifies the value of the primary capability.
|
From page 36... ...
Transient Location Information Management The ability to manage information about the availability of devices based on their location is an enabling technology for many of the applications discussed in this report. In the case of mobile devices, the situation is complicated by the fact that location information is transient.
|
From page 38... ...
suggested using location awareness to guide a mobile user from a bandwidth-impoverished to a bandwidth-rich environment. This is an example of an emerging technique, "cyber foraging," that temporarily extends the resources of a mobile computer by pointing to remote resources that are found opportunistically.
|
From page 39... ...
Additional investigation is needed to establish reliable and cost-effective techniques for monitoring mobile resources, discovering resources as they come in and out of service, partitioning and off-loading computation, and staging data. Because energy is a particularly critical resource in mobile computing, the research investment should include location- and orientation-sensing techniques that adapt to battery state.
|
From page 40... ...
The spoofing of user identity or of current location is difficult to guard against, making it difficult to tell whether a particular user was at a particular location at a particular time. Credible solutions to these problems are required if independent location-service providers (LSPs)
|
From page 41... ...
In that case as opposed to a vertically integrated system, in which one business provides the functions at all layers issues will arise if there are inadequate incentives for cooperation and information sharing. For example, location sensing may be an inherent component of a wireless Internet service it is needed to support the wireless service but the associated information might not be usable by a separately provided health-care application, such as the monitoring of patients after open-heart surgery.
|
From page 42... ...
42 IT ROADMAP TO A GEOSPATIAL FUTURE Applications The availability of location-sensing information has begun to stimulate innovative applications, such as sensor networks (see Box 2.2) and many of the examples already noted.
|
From page 43... ...
Golledge and his colleagues have developed a geographical information system for a GPS-based personal guidance system for the visually impaired (Golledge et al., 1998~. The spatial database component of their system is one example of the collection and use of geospatial data to obtain information about objects in real time in a real-world context.
|
From page 44... ...
sound foundation for e-government and other applications of information technology throughout society depends on a continuing, broad, federal computer science program." The report further suggests that the "rapid growth in the past decade was also based on the acceptance of an evolving set of common standards that enabled scaling up, competition, and interoperation. The development of the Internet suite of protocols, along with the establishment of processes for evolving them, is perhaps the most widely recognized example.
|
From page 45... ...
1997. "Agile Application-Aware Adaptation for Mobile Computing." In Proceedings of the 16th ACM Symposium on Operating Systems Principles, October.
|
From page 46... ...
2001. "The Cricket Compass for Context-Aware Mobile Applications." In Proceedings of the Seventh Annual International Conference on Mobile Computing and Networking, July.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.