Performance assessment of mobility solutions for IPv6-based healthcare wireless sensor networks

This thesis focuses on the study of mobile wireless sensor networks applied to healthcare scenarios. The promotion of better quality-of-life for hospitalized patients is addressed in this research work with a solution that can help these patients to keep their mobility (if possible). The solution proposed allows remote monitoring and control of patients’ health in real-time and without interruptions. Small sensor nodes able to collect and send wirelessly the health parameters allow for the control of the patients' health condition. A network infrastructure, composed by several access points, allows the connection of the sensor nodes (carried by the patients) to remote healthcare providers. To ensure continuous access to sensor nodes special attention should be dedicated to manage the transition of these sensor nodes between different access points’ coverage areas. The process of changing an access point attachment of a sensor node is called handover. In that context, this thesis proposes a new handover mechanism that can ensure continuous connection to mobile sensor nodes in a healthcare wireless sensor network. Due to the limitations of sensor nodes’ resources, namely available energy (these sensor nodes are typically powered by small batteries), the proposed mechanism pays a special attention in the optimization of energy consumption. To achieve this optimization, part of this work is dedicated to the construction of a small sensor node. The handover mechanism proposed in this work is called Hand4MAC (handover mechanism for MAC layer). This mechanism is compared with other mechanisms commonly used in handover management. The Hand4MAC mechanism is deployed and validated through by simulation and in a real testbed. The scenarios used for the validation reproduces a hospital ward. The performance evaluation is focused in the percentage of time that senor nodes are accessible to the network while traveling across several access points’ coverage areas and the energy expenditures in handover processes. The experiments performed take into account various parameters that are the following: number of sent messages, number of received messages, multicast message usage, energy consumption, number of sensor nodes present in the scenario, velocity of sensor nodes, and time-to-live value. In both simulation and real testbed, the Hand4MAC mechanism is shown to perform better than all the other handover mechanisms tested. In this comparison it was only considered the most promising handover mechanisms proposed in the literature.Fundação para a Ciência e a Tecnologia (FCT

A sudden death prevention system for babies

The growth of the smartphones market share has driven the entry of a large number of new opportunities to launch new applications/mobile tools both by companies but also by individuals’ entities. The prototype solution presented here fits in the increasing emerging of smartphones applications for the health sector. This dissertation presents a solution to prevent a sudden infant death syndrome. It includes biofeedback monitoring of babies, using body sensors to collect data that will be presented in two different mobile applications: the Main Application and the Client Application. Breathing, temperature, position, and heart rate are used, and placed to the baby’s body. The Main Application will receive the data collected by the sensors via Bluetooth. This contains a monitoring tool, which parses and transforms raw data to be readable and understandable for users. This application will send the data to a Web service to be stored in a database that supports the entire created solution. The Client Application will consume the data stored in the database every previous second. Both applications have an important functionality that allows the trigger of alert notifications when an error occurs with the data collected by the sensors and the caregiver is informed with an alert in a short time. This document describes in detail the whole process done to deploy a prototype that demonstrates and validates the proposed solution and is ready for use

Activity recognition based on thermopile imaging array sensors

With aging population, the importance of caring for elderly people is getting more and more attention. In this paper, a low resolution thermopile array sensor is used to develop an activity recognition system for elderly people. The sensor is composed of a 32x32 thermopile array with the corresponding 33° × 33° field of view. The outputs of the sensor are sequential images in which each pixel contains a temperature value. According to the thermopile images, the activity recognition system first determines whether the target is within the tracking area; if the target is within the tracking area, the location of the target will be detected and three kinds of activities will be identified. Keywords- Activity Recognition, Raspberry Pi, Thermopile, Imaging Processing