A sensor is a device used to measure a physical quantity – temperature, pressure, and/or movement, for example – and to convert that measurement into an output signal for further human or computer processing. In the field of domestic preparedness, a sensor is a device that detects a natural disaster such as a tornado, a flood, a tsunami, or an earthquake and forwards that information into systems that evoke a response that will save lives and property. Although disasters are unpredictable, the sensor technology already exists that can signal, often within seconds, the time a disaster begins.
Although sensors have been developed that detect the very moment of a disaster’s beginning, and some of these sensors are already in place, most nations throughout the world still rely primarily on their own human senses to detect disasters. Some countries such as the United States also use Doppler radar in certain situations, and alert the public, through the use of civil-defense sirens and broadcast warnings over local radio and television stations, that a major weather-related disaster might be imminent.
When one considers the suffering caused by the loss of lives, and the injuries incurred, when disaster strikes, and the worldwide annual economic cost of disasters (approximately $400 billion, according to a November 2007 Ceres Report, From Risk to Opportunism, by Evan Mills), it is reasonable to ask why earth-bound and remote satellite sensors are not used more extensively, on a worldwide basis, to provide the precious additional seconds or minutes of warning that could easily translate into reduced deaths, injuries, and property damage.
The High Cost of Inexplicable Delay
To understand the reasons behind the delay, it is important to recognize that sensors are only one component of larger and more complex geospatial information systems that distribute, gather, and process information about disasters. In other words, it is not as simple a matter as a two-step smoke-alarm process in which a stand-alone sensor device detects smoke and automatically triggers an alarm. However, the disaster information now gathered from sensors not only allows rapid response, but also permits the sensor data to be quickly gathered, stored, and processed for disaster recovery, mitigation, preparedness, and prediction.
But the question remains: With the advanced computer technology now available, why is there such apparent reluctance to use sensor technology more extensively? It would stand to reason that, with worldwide disasters costing an estimated $400 billion per year, most of the world – its land, seas, and skies – should by this time be automatically monitored by a global geo-sensor network to lower both the economic costs and the number of lives lost because of disasters.
The problems involving the use (or, in this case, non-use) of a global sensor network are caused, in large part, by difficulties in information sharing. Although not as plagued by the stigma of trust and security issues related to the sharing of national-defense and homeland-security information, the world’s sharing of disaster information is still hampered by the lack of interoperability of current disaster-information systems. One at least partial solution to this problem might be the development of international consensus-based interoperability standards that facilitate and improve information sharing through the use of harmonized software, hardware, and processes that are openly accessible to all of the world’s government and industry disaster-management stakeholders, emergency responders, scientists, and decision-makers. There seems to be no good reason, in fact, why such information should not also be available to the general public, which means that part of this solution would be to make such geo-information both rapidly accessible and free of charge through both the World Wide Web and the hand-held devices carried by individual citizens.
Encouraging Progress, But Formidable Obstacles Remain
Fortunately, there are several international geospatial consortia that have been working for some time on integrating data and systems to help in disaster-management situations. There also has been accelerating interest, enthusiasm, and rapid growth in this area of standards development, which is particularly important when one considers the numerous technological, political, and economic factors that must be taken into consideration before a global consensus and standardization in this area can be achieved.
Those factors include, but are not limited to, the following: the use of wireless sensors vs. non-wireless sensors; adding intelligence to sensors; the positioning and spacing of sensors; data communications and data development; the mining and processing of information; spatial and temporal granularity; the incorporation of data received from multiple sources; the validation, accuracy, and precision of the data received.
When one adds to that list various social and institutional hurdles, human user issues, the middleware for pervasive computing, the automatic acquisition of data, the accessibility of data, various ethics issues, data updating and harmonization requirements, energy constraints, and the management of massive volumes of sensor data it quickly becomes apparent why the development of a global disaster-information network is such a formidable challenge.
A Growing Consensus for Increased International Cooperation
For those working in the disaster-management field who wish to know more about progress made in the area of sensors and/or want to be included in the process of developing standards for sensors – and/or for the interoperability of associated geospatial information systems – the Open Geospatial Consortium (OGC) is a very active U.S.-based organization that focuses on the development of open standards for sensor networking; the OGC already has close to 400 members, many of them key representatives of the international geospatial community.
At this time, OGC has five proposed and adopted SWE (Sensor Web Enablement) specifications, and harmonizes its work with other geospatial standards and standards developers, including the standards developer IEEE (Institute of Electrical and Electronics Engineers), which has produced voluntary consensus standards for developers of intelligent transducers (sensors) and their information-sharing interfaces. (See a family of IEEE 1451 standards at https://standards.ieee.org/.)
OGC’s SWE standards enable sensor developers to fit their devices to agreed-upon criteria so that sensor information is accessible, in standard code, and able to be manipulated using standard protocols and standard application interfaces. OGC’s SWE standards and specifications provide a way for potential users to find the location of sensors, and to access published data on sensors of interest. The OGC SWE Standards Framework includes the following:
OpenGIS (Geographic Information Systems) Observations and Measurements (O&M) Best Practices Document, which serves as a model for representing and exchanging observation results, and is accompanied by an OGC Best Practices Paper on “Units of Measure Use and Definition” that covers XML (extensible markup language) details;
OpenGIS Sensor Model Language (SensorML) Implementation Specification v0.0 (05-086r2) – which provides an information model for the discovery and manipulation of web-based sensors and their data;
OpenGIS(R) Transducer Markup Language (TML) Implementation Specification v0.0 – which is basically a standardized transducer (sensor) message format that facilitates accessing, exchanging, and storing sensor data;
OpenGIS(R) Sensor Observation Service (SOS) Implementation Specification v0.0, which defines an application program interface that provides a standard way to access information from all sensor systems; and
Sensor Planning Service (SPS) Implementation Specification v0.0, which helps large enterprises in sensor planning vis-a-vis large information flows of both live and stored sensor and imaging data.
A Final Footnote: Considering the urgent need for sensors to detect and disseminate disaster information on an international scale, it is heartening to review – at (https://www.ogc.org/) the list of OGC members, which include technical, strategic, and principal members representing well-funded and well-staffed sensor and geospatial initiatives in progress all over the world. Despite the interoperability difficulties inherent with information sharing, therefore, it seems clear that, with this level of effort, geo-sensor networks are now in the making that will facilitate disaster management, reducing loss of lives and property on a worldwide scale.
Diana Hopkins is the creator of the consulting firm “Solutions for Standards” (www. solutionsforstandards.com). She is a 12-year veteran of AOAC INTERNATIONAL and former senior director of AOAC Standards Development. Most of her work since the 2001 terrorist attacks has focused on standards development in the fields of homeland security and national defense. In addition to being an advocate of ethics and quality in standards development, Hopkins is also a certified first responder and a recognized expert in technical administration, governance, and process development.