In case of emergency, the coordination of different services deals with different working methods, different languages, different instruments, different sensors and different data representations. Thus, the coordination of services includes heterogeneity problems that can be managed with the help of ontology matching techniques. In this paper we present a scenario where the requirements for ontology matching arise from emergency evacuation plans, in the specific domain of civil protection applications. We envisage what kind of smart sensor technologies could be used to support critical decisions when heterogeneous sources of information have to be matched.
In the context of semantic web and web services, heterogeneity represents a key
feature. One of the critical issues of semantic web services is the way the resources
of the semantic web have to be integrated as a whole. In fact, the ontologies
that are used to express information by means of sets of discrete entities (e.g.,
classes, properties, rules) are affected by heterogeneity, which requires proper
integration techniques [
For example, when a large–scale disaster occurs many people from different
organizations may reach the critical area in a short time, and the need for
integration of heterogeneous and rapidly evolving sources of data emerges. In this
context disaster management is strongly related, at different levels of
abstraction, to environmental monitoring and ambient computing [
In order to design flexible services in such extreme conditions, defining the
ontologies of the various smart devices employed (along with their capabilities)
and implementing suitable matching strategies is a viable and effective approach
[
This paper presents a potential real-world scenario where the ontology matching requirements are related to the management of emergency evacuation plans from large buildings. In particular, we envisage how management of emergency evacuation plans from large buildings can take advantage from ontology matching. The case study considered in the following, although still at a quite preliminary stage, results from a close collaboration between the Civil Protection Department, various research centers and local companies, and with the help of both staff members and volunteers of various rescue corps.
The rest of the paper is organized as follows: Section 2 introduces the basic issues related to emergency situations and specifically describes the requirements of the emergency evacuation plan scenario posed to ontology matching. Then, Section 3 summarizes the conclusions and outlines future work. 2
In case of emergency, an effective coordination of people from different organizations (e.g., civil protection, police, ambulance, fire brigades, red cross) is essential. The services offered by such organizations are characterized by different working methods, different languages, different instruments, sensors, and data representations. Thus, the coordination of services certainly includes problems requiring ontology matching. Several monitoring systems can indeed collect data for different organisations and for different purposes, using different sensor technologies.
Although the different solutions deal with huge amount of data, the interpretation and analysis is not consistent. Proper standardisation of data collection processes is necessary, including applied technology and data storing formats, to facilitate communication between services on a more consistent basis. Also, uncertainty over the network consistence arises during emergencies (e.g., in terms of sensors full functionality, or possible interaction that may occur with robots or automated agents with own sensors), as exemplified in Fig. 2. 2.1
As presented in Sec. 1, applications evolve in changing environments where
devices are replaced and added, and then it is not possible to establish unique and
definitive ontologies. Thus, applications have to be expressed in terms of generic
features that are matched against the actual environment. An interesting civil
protection applicative scenario, in which smart sensor networks could be
particularly useful, concerns with the optimal management of emergency evacuation
plans from large buildings. As known, all public buildings (e.g., offices, shopping
malls, schools) are usually equipped with a certain number of safety exits as well
as by evacuation plans that should be carefully respected, in particular in case
of dangerous events (e.g., fires or earthquakes). Usually, the basic safety
requirements are defined by national regulations. However, the actual effectiveness of
any pre-set evacuation plan can be limited by several issues, such as the
impossibility for occasional visitors (e.g., customers) to know the evacuation strategy,
the unpredictability of crush behavior in panic conditions, the lack of
information about number and about the distribution of people inside the building. To
solve such problems a smart sensor network could be deployed in a building in
order to automate the whole evacuation process. This network might consist, for
instance of:
– Redundant smoke or gas sensors to detect the presence of fire or the risk of
an explosion (redundancy is essential in this case to reduce the risk of false
alarms);
– Low-cost micro-electro-mechanical accelerometers for seismic events
monitoring [
The data collected by the various sensors could be transferred through wired or wireless connections (e.g., Ethernet or Wifi) to a central server (suitably connected to an emergency Uninterruptible Power Supply, UPS) which in turn could activate visual or sound alarms in order to manage the evacuation process in the safest possible way. For instance, when a fire is detected, a software application running on the server could estimate the level of risk in each area of the building and then switching on the emergency signals and the way-out light indicators, keeping into account the position and the distance of different users from the impending danger. In this way, people could be safely and orderly guided towards the safest exits, and in addiction the intrinsic risks related to a mass evacuation (especially for children, for elderly people and for people with disabilities) could be significantly reduced. 2.2
Usability of devices depicted in Fig. 2 is unpredictable since they are subjected
to being added/replaced or malfunctioning at any time. For instance, when a
robot enters a building during evacuation, it will introduce sensors that will
provide more precision or information which has not been considered at application
design time and again ontology description languages can help solving this
problem [
From this scenario we can derive requirements for matching solutions in the
context of emergency evacuation plans. In particular, requirements concern
specific behaviours, such as requirements of being automatic (not relying on user
feedback), being correct (not delivering incorrect matches), being complete
(delivering all matches) and being performed at run time. These requirements
confirm the application requirements reported in [
In this paper, an applicative example is proposed in which the joint application
of both ontology matching strategies and smart sensor networks can be
successfully used to optimize building evacuation. Multiple sensors could be used
to estimate in real–time the total amount of people and their distribution in
the building, while proper matching of the sensor ontologies should facilitate
and greatly improve the decision making process. Future works include studies
to elaborate and to formalize the scenario, to choose and to develop a suitable
matching algorithm (e.g., as in [