Digital Earth's Nervous System for crisis events: real-time Sensor Web Enablement of Volunteered Geographic Information

Figures & data

Table 1. Functional comparison of the human nervous system and the Digital Earth Nervous System.

	The Human Nervous System		The Digital Earth Nervous System
Concept	Touch sense	Vision sense	VGI sensing	Remote sensing
Stimulus	Something changes on the body surface, expressed in heat, pressure, itchiness and/or pain	Something changes in the environment, expressed in movement, shape and/or colour	Something changes where there are people that can and want to report it	Something changes that can be observed by a (constellation of) satellite-embarked sensors
Sensor	Specific receptors in the skin, tongue, throat and mucosa convert stimuli in electrochemical waves	Cone and rod cells situated in the eyes convert stimuli in electrochemical waves	Information is digitised (using smartphones, computers, GPS, etc.)	Waves reflected or emitted by remote objects are digitised according to sensor specifications
Sensation	An organised set of measurements is created in the brain	A mental image is created in the brain	Heterogeneous information is centralised and organised is a complex set of measurement results	n-Dimensional remote sensing images are created
Perception	Patterns are recognised in touch sensations and compared to memory for identification and characterisation of features	Feature in the image are discriminated and compared to memory for identification and characterisation	Complex measurements are analysed for identifying events and situations	Images are processed to provide derived information, features are identified using prior knowledge
Attention	Relevance is assigned according to context	Relevance of such features is assigned according to context	Alerting mechanisms are triggered according to context	Alerting mechanisms are triggered according to context
Reaction	Further nervous systems functionalities are mobilised, and a prioritised list of activities is created, and including: instinct (fast, simple) reactions; evaluation of information lacks; request to other senses for more information; movements.		Sensor network information is integrated in crisis information systems, where appropriate tasks are prioritised, related to: early response; situation awareness, request for additional information; mitigation actions; damage assessment.

Figure 1.  Interplay of SWE components.

Figure 2.  SWE for VGI sensing (capabilities listed in Figure 1 remain).

Table 2. Mapping between general concepts of the nervous system and SWE for VGI sensing.

Concept	SWE notion	Example for VGI sensing
Stimulus	Observed property	Environmental changes caused by a crisis situation
Sensor	Raw data SOS (encapsulated device that digitise stimulus and provide property values)	SOS-encapsulated smartphone data
Sensation	Raw data collection SOS (encapsulated network of devices or time-series of a single device)	SOS-encapsulated collection of VGI that is organised and has a given focus (time, geography and theme)
Perception	Value-added information SOS (encapsulates clustering algorithms etc.) SAS (as situation-aware component)	SOS-encapsulated identification of VGI clusters (thanks to additional data and contents analysis) SAS part setting hot spots into context, i.e. filter the important hot spots according to pre-calibrated constraints
Attention	SAS (as alerting component)	SAS part using CAP to inform crisis manager
Reaction	Decision-support system (can include SPS)	SPS for satellite tasking