Ontology-Based Service-Oriented Architecture for Emergency ...

Ontology-Based Service-Oriented Architecture for Emergency Management in Mass Gatherings

Pari Delir Haghighi

Frada Burstein

Monash University Melbourne, Australia [email protected]

Monash University Melbourne, Australia [email protected]

Hasn Al Taiar

Paul Arbon

Monash University Melbourne, Australia [email protected]

Flinders University Adelaide, Australia Paul.Arbon@ flinders.edu.au

Shonali Krishnaswamy Monash University Melbourne, Australia [email protected]

Abstract—To achieve timely response and treatment of life threatening injury or illness in mass gatherings, it is imperative to establish effective communication and coordination between emergency agencies and teams and provide them with ready access to real-time information. The service-oriented paradigm presents an elegant solution for developing a general and scalable architecture where emergency teams can utilize services for situationalawareness and collaboration. In this paper we propose an ontology-based service-oriented architecture for mass gathering health services that can be implemented using stationary servers or peer-to-peer models. We describe the preliminary implementation of the service-oriented system using an Android phone. Keywords-component; ubiquitous computing, managment

I.

context-awareness, decision support,

ontology, emergency

INTRODUCTION

Mass gathering environments are typically very dynamic and uncertain where emergency decisions need to be made under time pressure [1]. Achieving effective interaction and collaboration among various emergency services in such events is a complex and challenging task. When a crisis occurs, emergency medical teams who are geographically distributed across the venue have to make split-second and complex decisions. These decisions heavily depend on access to up-to-date information and situational awareness, especially concerning the status of other teams. Situational awareness here refers to any information related to the effective management of emergency events and may include information about the

location of each team or their resources with regard to medical equipment or staff. To achieve timely response and treatment in mass gatherings, it is imperative to establish effective communication and coordination between different emergency teams and provide them with easy access to real-time information. Recent advances in mobile communication coupled with increased computational capabilities of mobile devices present an unprecedented opportunity for situation-aware and mobile applications. These applications can be very beneficial to emergency medical services as they are able to provide emergency teams with ready access to the status and location of dispersed emergency resources using their mobile phones. This is particularly important because medical response is usually tiered with an initial urgent response and assessment team relying on subsequent specialist teams if required. One of the most recent and potential approaches for developing distributed and mobile applications that enables information sharing and collaboration is service-oriented computing. The Service-Oriented Architecture (SOA) enables logical representation of a software system using a collection of services and supports interoperable, selfdescribing and loosely coupled systems [2, 3]. Web services present a promising and standard technology for developing self-contained and modular applications that can be accessed via the Internet [4]. Examples of emergency management applications that practice service-oriented architecture include emergency decision model [5], Escape [6], the SHARE system [7], and the Medigrid framework [8]. While these systems aim to improve emergency management and team collaboration, they have limited support for mass gathering

events and they do not consider the issues that are specifically related to the provision of medical care in such events (i.e. crowd mood, weather or the venue structure). In the context of mass gatherings, the service-oriented architecture can be used to publish, dispatch and access up-to-date information about emergency teams including their current location on a mobile phone. Such infrastructure enables any system supporting web services specification to be dynamically located and communicate with other web services regardless of their location [5]. This paradigm presents an elegant solution for developing a general and scalable architecture for mass gathering events where emergency teams can utilize services for situation-awareness and collaboration. To facilitate the collaboration and information sharing among emergency services and agencies in mass gatherings, in this paper we propose an ontology-based service-oriented architecture that enables publishing and accessing useful information using mobile phones. Our proposed architecture applies a domain ontology named DO4MG (Domain Ontology for Mass Gathering) [9] to provide a standard and unifying knowledge model for sharing information and enabling user queries and inferences. The DO4MG contains the key concepts of emergency management in mass gatherings as well as their characteristics and relationships, and presents a standardized knowledge structure/model that can be shared between various emergency medical stakeholders and event planners. The proposed ontology-based SOA aims to provide effective communication and cooperation among distributed emergency teams in mass gathering events. We present the details of the preliminary implementation of service-oriented approach and the conducted simulation using real mobile phones. This paper is organized as follows. In Section 2, we discuss challenges in achieving effective collaboration among emergency services in mass gatherings and present an illustrative scenario. In Section 3, we discuss our proposed ontology, DO4MG, and its strengths to provide a unifying knowledge structure of the domain that can be shared across different services. Section 4 describes the service-oriented architecture and its components. Section 5 details the implementation and simulation of SmartLocator4MG system based on the described scenario. Finally, Section 6 concludes the paper. II.

EMERGENCY MEDICAL MANAGEMENT IN MASS GATHERINGS (EMMMG)

A Mass gathering can be defined as a temporary collection of large numbers of people “where there is the potential for a delayed response to emergencies because of limited access or other features of the environment or location” [1]. Due to the crowd size, density and mood as well as other environmental factors, mass gatherings potentially increase the degree of vulnerability of those attending the event and the likelihood of life-threatening situations. Planning and managing a mass gathering event require involvement of various emergency services and stakeholders such as emergency medical services, police,

event security personnel, and venue owners. The study reported in [10] reveals that emergency medical decisions made by one team highly depend on, and can affect, the decisions of other teams. These decisions relate to timely treatment of injured or ill patients, more advanced levels of medical care where this requires rapid evacuation of patients to nearby hospitals, requests for external and additional resources and maintaining the safety of the crowd. One of the main challenges in staging a safe mass gathering event is the coordination of emergency agencies to ensure an effective and rapid response to threats to the health or safety of the crowd [11]. Generally during an event, emergency services are widely distributed (geographically) across the venue. When an emergency occurs, emergency response teams need to interact and communicate with each other to obtain up-to-date information about the response(s) required, the situation, available resources (i.e. medical equipment), number and type of staff available (e.g. nurses) and the number and severity of patient presentations. An additional important element is knowledge of each team’s location, their proximity to each other, particularly when these teams are mobile, and their response status (e.g. committed or available for response). Access to useful and real-time information enables emergency commanders to coordinate allocation of resources and staff in more effective manner and provides them with the opportunity to ensure that mutual support is available across different emergency services/agencies. For example, where an emergency resource is duplicated, for example between the local ambulance authority and the on-site emergency medical service decisions can be coordinated regarding which service responds to which event with what resource. Without this knowledge, it is very difficult for on-site commanders to make effective decisions and coordinate the response to each emergency call-out. The following scenario provides an example of this challenge. A. An Illustrative Scenario Consider a mass gathering event (i.e. a horse racing event with approximate 60,000 attendees) which is held between the hours of 10:00 to 16:00 at Caulfield Racecourse in Melbourne, Australia. At the start of the event, emergency services and agencies including volunteer health professionals, medical teams, first aiders, police, security and paramedics were located at the venue. Clinical facilities included basic first aid and advanced life support including one semi-automatic defibrillator which was allocated to the site medical team. Two ambulances were also situated at the venue. At 13:00, the first aiders and medical teams were busy attending to several people for, minor complaints including headache and sunburn. The site medical commander received an urgent call from event security who had been advised of a patient collapsed and apparently in cardiac arrest on the far side of the racetrack. Using simple hardcopy site maps the mobile

first aid patrol considered to be nearest to the patient’s location was dispatched. A second team was sent from the site medical centre carrying advanced life support equipment and the defibrillator and an ambulance crew was placed on stand-by to attend the scene should this be required. Police and the event and venue owners representatives were advised of the emergency and the Police Commander dispatched a mobile team to assist at the scene event management and security prepared to assist with ambulance access and egress through the most appropriate perimeter gate of the venue Under considerable time pressure, the first aid commanders had to locate and dispatch the nearest first aid team, locate and dispatch the site medical team and advise agencies to respond or prepare to respond to a life threatening emergency. As evidenced by the above scenario, access to useful real-time information about the participating teams and their status, the availability of transportation services or nearby hospitals and emergency communications contacts with other agencies are essential to the timely treatment and extrication of patients in the difficult context of a mass gathering. These challenges can addressed by providing emergency response agencies with a smart environment in which all commanders and team members can readily access real-time information about the emergency situation and interact with this information to ensure an effective response using their mobile phones. III.

THE ROLE OF ONTOLOGIES

Effective communication among emergency stakeholders relies upon the use of common agreed terminology and the employment of standard cross agency emergency plans, including especially mapping of the site and site resources. Ontologies have been widely used to provide a formal and unifying representation of the concepts within a certain domain that can be shared and reused [12, 13]. An ontology presents ‘a vocabulary that describes a domain of interest’ using the major concepts and terms applied in that domain and identifies the relationship between these concepts [14]. An ontology provides a world view and the shared understanding of a given domain which can be used as a unifying framework to address the domain problems [15]. As Gruber [16:1] suggests “an ontology is an explicit specification of a conceptualization”. An ontology for mass gathering results in a better understanding of these events, their characteristics and relationships and causal factors. Such standard conceptual models can be then applied across all events and facilitate coordination and communication between different teams [1, 12].

Figure 1. The key concepts of DO4MG.

The literature on mass gatherings reveals that current studies focus on certain events and their related characteristics and they do not provide an adequate general knowledge structure that can be shared between various emergency medical stakeholders and event planners [1]. In [9] we introduced a domain ontology for emergency medical management in mass gatherings, named DO4MG (Domain Ontology for Mass Gatherings) that provides a formal and unifying conceptual model of emergency management in mass gatherings that can be applied across all events. Fig. 1 depicts the five main concepts of mass gatherings which include Environmental Factors, Crowd Features, Event Venue, Mass Gathering Plan and Gathering Type. The DO4MG ontology is implemented in Protégé 4.0. which supports OWL (Web Ontology Language) [17]. OWL is an ontology language used to define and describe the concepts (classes), subclasses, properties, and associated relationships of the domain of interest. As Fig. 1 shows DO4MG consists of five main classes (i.e. parents) at the first level of class hierarchy. These classes are broken into further subclasses. There are five levels in the ontology hierarchy (i.e. the depth). The total number of classes considering all the levels is 146. Fig. 2 illustrates subclasses of Crowd Features, Environmental Factors, Event Venue and Mass Gathering Plan. Inclusion of DO4MG in our proposed serviceoriented architecture enables sharing information in a standard and uniform manner between various emergency agencies and stakeholders. More importantly, ontologies are essential for enabling querying and reasoning data. Ontologies provides an intelligent and effective way for searching/querying information and discovering services [18, 19]. The next section describes the ontology-based service-oriented architecture for mass gatherings.

Figure 3. An overview of centralized mobile SOA for mass gatherings.

Figure 2. An overview of DO4MG subclasses.

IV.

THE SERVICE-ORIENTED ARCHITECTURE

In this section we introduce an ontology-based and mobile service-oriented architecture for emergency medical management in mass gatherings that aims to enable effective information sharing and collaboration among emergency teams during the events. This architecture uses mobile phones to publish and/or access services. The mobile service-oriented architecture can be generally implemented in two ways. These include statichosted and mobile-hosted mobile web services [18, 19]. Static-Hosted Mobile Web Service (SHMWS) use mobile devices for consuming services but rely on central and stationary servers for registering and discovering services. Mobile-Hosted Mobile Web Services (MHMWS) use only mobile devices for publishing and consuming web services [20, 21]. Our proposed architecture includes a static host (i.e. the stationary server) and uses mobile phones as web service clients. A. Ontology-Based Service-Oriented Model The ontology-based service-oriented architecture consists of mobile devices that request services and a stationary server where the central directory is located and performs registry and discovery (shown in Fig. 3).

The other components of this architecture include the domain ontology, Query Engine, Ontology Reasoner, and a GPS Locator. As Figure 3 shows the remote static host includes a GPS Locator to provide location information. The Ontology Repository contains the domain ontology for mass gathering domain (i.e. DO4MG). This ontology enables reasoning and querying information performed by Ontology Reasoner and Query Engine respectively. In our proposed architecture, Mobile devices enable emergency agencies and teams who are geographically distributed across the mass gathering venue to register and then be able to access and share real-time information (including current location) about other teams. The next section details the preliminary implementation and simulation of the centralized mobile service-oriented for mass gatherings. This preliminary work does not include the DO4MG ontology and reasoning capabilities but we are now working towards adding these features into the system. V.

IMPLEMENTATION AND SIMULATION

The SmartLocator4MG (Smart Locator for Mass Gathering) application is implemented in java as the preliminary prototype of the centralized service-oriented architecture for mobile environments. SmartLcoator4MG is a mobile location tracking system designed to assist emergency services and agencies in mass gathering contexts with making time-critical decisions. The system aims to facilitate communication and coordination between the distributed teams by providing them with a real-time view of their status and location. Fig. 5 shows the architecture of SmartLocator4MG and its main components. Our implementation targets the Google’s Android mobile phones for the front end, and PHP web service and MySQL database for the back end. The current application uses generic RESTful web service for the client-server communications and SQL server for storing the details of emergency personnel. The application contains the following components:

Google map and their status using three colors of white, yellow and red that corresponds to three emergency levels of available, responding and committed. This task is performed by the Visualization Manager.

Figure 5. An overview of DO4MG subclasses.

At the client side: 1. The GPS Receiver – SmartLocator4MG is a location aware application and therefore all the client platforms need to be equipped with a GPS receiver that can pick up the Satellite signal for tracking the location of emergency teams in the field. In our implementation, Google Android mobile phone was used as it has a GPS sensor built in it. 2. Location Manager – The location manager is responsible for monitoring emergency staff’s positions and then passing the details to the Visualization Manager. The Location Manager updates the location information of stakeholders through the central directory. 3. Query Engine – The Query Engine component aims to facilitate the continuous user queries made by the client application. In order to keep the user well-informed about all other teams, the client application queries the central directory about the other team’s position, names, contact info, as well as their level of resources. 4. Web Service Client – This component is responsible for structuring and controlling the messaging with the Web Service provider on the server end. We have implemented our client in Java to be generic and adaptable to any restful web service as long as it provides similar structure of data using Json Technology [20]. 5. Communication Manager - The Communication Manager component performs structuring and controlling of the messages passing across our Google Android mobile applications and the central directory. The communication channel is made through a generic RESTful web service that resides on the server side. Communication Manager controls all the communications between our central directory (the back end), and the Google Android mobile Application (the front end). Since our application requires handling a large number of messages passing to update the location of all stockholders, it was necessary to use optimization techniques for reducing the amount of unnecessary messages and bandwidth usage. For instance, instead of continuously updating the Geo-location of the clients at the server side, a distance movement threshold is used for clients. If the movement distance is greater than this threshold the update message is sent to the server. 6. Visualization Manager – SmartLocator4MG displays the location of emergency teams as circles on the

At the server side: 1. Central Directory - The Central Directory component performs registration of clients, storing their details, updating location information and service discovery. To access the information about the situation of emergency teams, the mobile user first needs to register their application to the central directory. Then all the clients can access the new registered user’s information. 2. PHP Web Service Broker consists of three subcomponents as follows: • RESTful Web Service Provider – This component can be seen as a wrapper of the Communication Manager and the Query Handler to provide a generic way of communicating with the other platforms across our system. Since the web service was written in PHP, it is hosted on an Apache server. • Query Handler - This component is in charge of handling client application queries about other available stakeholders. • Communication Manager - The communication manager manages message passing and enables all the necessary communication across the network. 3. SQL Server – The MySQL database server is used for storing information about the registered stakeholders in the filed. The MySQL database is open source and it has a smooth compatibility with our Web Service Broker that was developed in PHP. 4. Google Map Service – The location of emergency teams are visualized on the map to provide location and situation-awareness such that all the participating teams in the field can clearly view who is available and what is their location and what is their level of resources. For doing that, Google Map Web Service is used. The next section describes the simulation of SmartLocator4MG. A. Simulation We have conducted a simulation of SmartLocator4MG using real Android mobile phones at the Caulfield Racecourse in Melbourne, Australia. The track has a triangular shaped layout, comprising three straights, 30 meters wide, with a total circumference of 2080 meters and a finishing straight of 367 meters. In this simulation we aim to demonstrate how centralized mobile service-oriented architecture can be used for accessing real-time information about the location and status of various emergency services across the venue. Moreover, we show how the information is visualized and accessed on the mobile phones to provide the participating teams with a better view and understanding of the emergency situation. This clearly leads to more effective decision making and resource allocation.

The status of emergency services and personnel is defined according to the combination of factors such as their capacity, available resources and number of patients. Three emergency status colors are used (i.e. white, yellow and red) that correspond to three emergency levels of available, responding and committed. The experiment was carried out using two real Android mobile phones at the Caulfield Racecourse. In the simulation we considered that the first mobile phone belonged to the team of first aiders (two people) and the second mobile phone was carried by police. Location tracking of the mobile teams was performed by obtaining real GPS location of the mobile phones. In addition to this real-time information, we also simulated and stored the location information for two emergency teams including one ambulance and one first aid team. We first started the SmartLocator4MG application on one of the mobile phones and registered the user as the first aider (top-left image in Fig. 6). During the registration, the user name and mobile phone number were entered and registered and also stored in the database. As soon as the registration was complete, the phone displayed a new white circle with the team’s label (top-right image in Fig. 6).

Figure 6. The registration and location tracking with SmartLocator4MG.

This new circle became visible in the other mobile phone as well. This verifies that all mobile phones registered with the directory can access global information at real-time. Moreover, the users can obtain the details of other teams just by tapping on the circle on the touchscreen of the mobile phone. This is depicted in the bottom-left image in Fig. 6. The details of the new registered team are displayed by tapping on the circle that represents them. We asked the user of the mobile phone to move around the venue and monitored their current location. The application dynamically picks up the new location and displays it on the map (bottom-right image in Fig. 6). The image displays the new location of the first aiders on the map. Another key feature of SmartLocator4MG is that it displays the current status of emergency services on the map by using three colors (i.e. available, responding or committed). Initially these colors are displayed as white. This visualization facilitates decision making during emergency because the decision makers can obtain a general view of the all the participating teams and their status at a glance. The left image in Fig 7. shows that the user is able to enter their emergency status (ranking from 1-3) and the right image illustrates how this change is visualized on the map and visible to all the users. With regard to our scenario, in this simulation the first aiders enter a level-three emergency situation because one of the patients is at early cardiac arrest and requires the automatic defibrillator immediately. Using the application, the first aiders can easily identify the location of medical team who is equipped with the defibrillator on the map. This detail can be entered during the registration and displayed on the phone when the circle representing them is tapped on. The displayed details also include the mobile number or communications network call sign and other relevant details of team make-up, roster and shift time or equipment that can be used to aid decision making regarding deployment of the team. This simulation demonstrates the benefits and potentials of our mobile application to provide emergency agencies with real-time and useful information about other distributed teams. Such information is essential for enabling timely emergency response and treatment of patients during these events.

Figure 7. Visualization of the status of emergency teams.

VI.

CONCLUSTION

In this paper, we proposed an ontology-based serviceoriented architecture for emergency medical management in mass gatherings using mobile phones. The absence of standardization of mass gathering concepts in medical emergency management hinders the interaction and coordination between different emergency services during mass gathering events and limits the effectiveness of decision support systems in such environments [1]. In times of emergencies and crises, it is crucial to access realtime and useful information to make effective decisions. Ontologies provide a formal and unifying vocabulary to represent and share the knowledge of a domain. We have developed a domain ontology for mass gathering that can be applied across varying emergency agencies. Inclusion of the domain ontology into a service-oriented architecture allows the access to data in a standard structure and makes it available to use on demand. Utilizing mobile web services in a peer-to-peer model provides a potential technology for publishing and accessing information about various emergency services during mass gatherings using mobile phones. The main advantage of such architecture is that it can cater for any event and venue and it is loosely coupled and platform independent. We described our preliminary implementation as the starting attempt towards this architecture. In future we intend to add the DO4MG ontology into the framework and enable peer-to-peer service-oriented model where there is no need for a central directory. In doing so, emergency teams are able to control publishing their data to other emergency teams using their mobile web service interface. We aim to make our ontology available as a web service and each emergency team can apply the parts of the ontology that relates to their tasks and operations. ACKNOWLEDGMENT This research is funded by Australian Research Council funding (LP0774834).

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