Angélica Reyes

Developing a body sensor network to detect emotions during driving

Emerging applications using body sensor networks (BSNs) constitute a new trend in car safety. However, the integration of heterogeneous body sensors with vehicular ad hoc networks (VANETs) poses a challenge, particularly on the detection of human behavioral states that may impair driving. This paper proposes a detector of human emotions, of which tiredness and stress (tension) could be related to traffic accidents. We present an exploratory study demonstrating the feasibility of detecting one emotional state in real time using a BSN. Based on these results, we propose middleware architecture that is able to detect emotions, which can be communicated via the onboard unit of a vehicle with city emergency services, VANETs, and roadside units, aimed at improving the drivers experience and at guaranteeing better security measures for the car driver.

A QoS-based dynamic pricing approach for services provisioning in heterogeneous wireless access networks

In this paper we propose a simple QoS-based dynamic pricing approach for services provisioning in a heterogeneous wireless access network environment which attempts to increase user’s satisfaction level by firstly, maximizing the provided QoS level, and secondly, by applying dynamic pricing strategies according to the QoS. These strategies will allow service providers to maximize their profits. Simulation results demonstrate that the proposed dynamic pricing approach benefits both users and wireless service providers (WSPs). Results also suggest that users have better overall satisfaction due to a better QoS level and fairer prices. The analysis shows that our proposed pricing approach contributes to an increase in WSPs profits compared to the application of the flat-rate pricing model in a competitive market-model.

A Clean Slate Architecture Design for VANETs

In this paper, VANET applications have been classified according to their purpose. Furthermore, a clean-slate architecture specifically designed for VANETs has been introduced. The proposed non-layered context-aware ubiquitous architecture adapts dynamically to changes, is oriented to services (VANET applications) and has a flexible structure. The vehicle and environmental context-aware information as well as the VANET communication characteristics are designed for the proper operation of the applications. In addition, the performance of Automatic Repeat Request and Forward Error Correction (FEC) block codes with respect to the throughput efficiency has also been analyzed for a VANET following the proposed clean-slate architecture. The numerical results show that the proposed clean-slate architecture outperforms the traditional layered architecture with respect to the throughput efficiency for both error control schemes. FEC block codes are able to maintain high throughput efficiency over longer distances because the hop length extension technique is applied.

Group-awareness for Mobile Cooperative Learning

Collaborative learning traditionally relies on the arrangement of space and physical artifacts to mediate group activities. Our claim is that CSCL environments should enhance collaborative learning in a complementary way without introducing additional burden to human participants. This paper present research results on how tracking the location of people could be used to incorporate automatic group awareness in existing and new CSCL applications that support mobile cooperative learning. After presenting the requirements and structure of a middleware to handle automatic group awareness based on location information, two applications are presented. Experiments in a real setting on a jigsaw activity, with students using laptops with WiFi on a university course, confirm the validity of using location technology to automatically derive group structure and the positive effect on the learning results.

Vehicle density in VANET applications

This paper analyzes how street-level traffic data affects routing in VANETs applications. First, we offer a general review about which protocols and techniques would fit best for VANET applications. We selected five main technical aspects (Transmission, Routing, Quality of Service, Security and Location) that we consider are differential aspects of VANETs from current Ad-Hoc Networks. Second, the paper analyzes how to configure each technical aspect according to the goal of a wide range of VANET applications. Third, we look at the routing aspect in depth, specifically focusing on how vehicle density af- fects routing, which protocols are the best option when there is a high/low density, etc. Finally, this research implements a sensor technology, based on an acoustics sensor that has been deployed around the city of Xalapa in Mexico, to obtain reliable information on the real-time density of vehicles. The levels of density were discretized and the obtained data samples were used to feed a traffic simulator, which allowed us to obtain a global picture of the density of the central area of the city. Ac- cording to the specific levels of vehicle density at a specific moment and place, VANET applications may adapt the routing protocol in a real-time way.