Thera praevenio: A community based early warning system

Disasters, whether natural or man-made, often results to multiple damages and great losses in terms of material possession and human lives. Vulnerability to hazards cannot be avoided but the damages can be reduced. This paper introduces the development of Thera Praevenio, a community based early warning and mapping system. Thera Praevenio attempts to lessen the impact of disasters by particularly focusing on the first two steps of disaster management namely mitigation and preparedness. Thera Praevenio is a work in progress that other researchers learn from and can continue. The Philippine experiences multiple typhoons yearly making flooding the most common and observable natural hazard that affects the urban communities. The Philippines is also a part of the countries in the pacific ring of fire and the possibility of earthquakes cannot be neglected. Fires, on the other hand, devastate urban communities because the compositions of the houses are highly flammable and are connected to each other. These disasters are magnified when the government, particularly the local government, is inadequate in managing emergency situations. These situations are often associated with the following: the lack of fast information dissemination, the lack of appropriate training for the community on protocols to follow during the calamity, and the lack of coordination among the government officials and their communities. The group conducted a study that is focused on the barangays at Leveriza, Manila. The civilians in the community have ease of access and of use to the following technologies: cellular phones, computers, and internet connection. As a result, Thera Praevenio was mainly composed of the following features: the utilization of Short Messaging Services (SMS), Google maps, social networking site (e.g Facebook and twitter), wiki pages, and generating reports. Each feature enables the community to enhance their process of disseminating the information, to attune the processes of handling hazards, to be prepared through collaborative community discussion and recorded training details, and to bridge the gap of communication between each officials and their community. Thera Praevenio is structured to function remotely and will be uploaded in a web server. The system can be updated through the use of computers or cellphones. With the use of defined SMS conventions, the group believes that the system can function even without internet connection or electricity. Thera Praevenio is not just for the community of Leveriza. The system can be used by anybody who wishes to register and subscribe to the system. The modules and functionality of the system are also flexible enough to be updated and be used for other locations. The system success is highly dependent to its users

Separating Obligations of Subjects and Handlers for More Flexible Event Type Verification

International audienceImplicit invocation languages, like aspect-oriented languages, automate the Observer pattern, which decouples subjects (base code) from handlers (advice), and then compound them together in the final system. For such languages, event types have been proposed as a way of further decoupling subjects from handlers. In Ptolemy, subjects explicitly announce events at certain program points, and pass the announced piece of code to the handlers for its eventual execution. This implies a mutual dependency between subjects and handlers that should be considered in verification; i.e., verification of subject code should consider the handlers and vice versa.However, in Ptolemy the event type defines only one obligation that both the handlers and the announced piece of code must satisfy. This limits the flexibility and completeness of verification in Ptolemy. That is, some correct programs cannot be verified due to specification mismatches between the announced code and the handlers’ code. For example, when the announced code does not satisfy the specification of the entire event and handlers must make up the difference, or when the announced code has no effect, imposing a monotonic behavior on the handlers.In this paper we propose an extension to the specification features of Ptolemy that explicitly separates the specification of the handlers from the specification of the announced code. This makes verification in our new language PtolemyRely more flexible and more complete, while preserving modularity