# A Semantic Framework for Decision Making in Forest Fire Emergencies
## 3 ONTO-SAFE Architecture  
A high-level description of the ONTO-SAFE framework's architectural design is presented in this section. More specifically, Figure 1 represents:  
* **Input data** are the data that the ONTO-SAFE framework is responsible for translating into RDF-based triples (_subject, property, object_). In particular, the ONTO-SAFE framework attempts to create a unified representation of the assets that are available by incorporating data from a number of sources, including weather forecasts, fire sensors in forests, earth observations from Copernicus and GEOSS, and social media and other applications that residents and emergency stakeholders can use to share information regarding the situation in the field. More specifically, the data obtained from weather forecasts encompass various weather-related factors specific to a particular location, including temperature, humidity, wind speed, and precipitation. The integration of these data assist in accurately assessing and anticipating weather conditions that could potentially contribute to forest fire emergencies. On the other hand, data sourced from the Copernicus system provide valuable insights into the landscape. This includes information about land cover, which aids in understanding the terrain and potential fire risk areas. Additionally, the Fire Weather Index (FWI) data derived from this system plays a crucial role in evaluating the level of fire danger across Europe, enhancing our ability to respond proactively to forest fire incidents. Moreover, data received from social media applications include information regarding the forest fire such as timestamp, location, media items, etc. These real-time data contribute to a more comprehensive understanding of ongoing forest fire situations. Furthermore, data obtained from fire sensors play an essential role in providing immediate and accurate information about forest fires. These data include timestamps, precise locations, and the direction of the fire, enabling quick and effective response strategies. The generated data are delivered in NetCDF, JSON, or GeoJSON format and analyzed by the ONTO-SAFE framework. * **ONTO-SAFE framework*
* is the central component that is responsible for the successful collection of the generated data from the various sources (i.e., earth observations, weather forecasts, sensors, social media, etc.) and analyzes and converts the input data into valuable information to produce the relative output data. The following components constitute the ONTO-SAFE framework:
* **Knowledge base repository (KBR)**, which supports the storage of the ontology and the results of a semantic process. KBR provides native RDF triple storage by providing a way to store RDF triples in a model similar to the graph model, and services to run complex queries on it in an acceptable time;
* **Ontology**, which is a set of concepts and categories for the representation of heterogeneous information that shows their types, properties, and the relationships between them. The ontology contains a large number of instances stored as RDF triples;
* **Knowledge base service (KBS)**, which hosts the core services (knowledge base population and semantic reasoning) and acts as the primary interface to the ONTO-SAFE ontology, is a key component of the system design;
* **Knowledge base population (KBP)**, which is in charge of supporting the semantic analysis process and implementing the mapping mechanisms when new or updated data are made available as input from intelligent services sources in order to populate the ontology with new facts;
Semantic reasoning, which executes semantic queries in the Ontology in order to retrieve alerts and recommendations that fulfill the criteria and return the results in JSON or GeoJSON format;
* **Output data** are the data of the semantic reasoning process which are sent as inferred, high-level information in JSON or GeoJSON format to other system components that are interested, such as the dashboard in order to inform properly the stakeholders (citizens and professionals).