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We propose a destination-based jamming scheme for cooperative networks with multiple untrusted amplify-and-forward relays, in which the destination operates in full-duplex mode so as to enable simultaneous reception of the information coming directly from the source and the transmission of jamming signals to the untrusted relay. An approximate analytical expression for the secrecy outage probability, under the effect of residual self-interference at the destination, is presented. The developed analysis is verified through Monte Carlo simulations.

The agricultural industry faces the challenge of increase yield and improve the food quality. This paper presents a study on the prediction of fruit production and also intends to detect other information that can be obtained based on the scans of fruit trees using a LIDAR sensor. We worked on a Williams pear orchard using a semi-automatic procedure in order to estimates tree volume. We compute the canopy area with a simple method based on the Gauss's formula at harvest and during tree dormancy. We correlates volume vs. weight of harvested fruits from each plant. Regression coefficients were obtained for individual and grouped data. At harvest time, we obtain a good relationship between the volume of the canopy and the production (r = 67). The information obtained is very valuable in terms of the general state of the crop, the evolution and distribution of production within the orchard, and to make adequate decisions about its management.

Summary form only given. We have developed a prototype that uses medium range smartphones running on the Android platform, to collect and register accelerographic data of the movement experimented by buildings or civil structures during a seismic event, in order to identify potential hazard of structural failures. At the moment the National Accelerographic Network, system managed by the Venezuelan Foundation for Seismological Research (FUNVISIS), uses an ETNA accelerographs platform to record and collect accelerographic data for the study and evaluation of seismic events. In this research we are interested in evaluating how good is the data collected by our prototype against the data that could be obtained by a current professional platform in order to identify the potential applicability of our prototype as a part of the FUNVISIS platform. Our prototype uses smartphones as a system of sensor nodes that are always in recording mode. The devices will be placed on specific fixed locations of a structure where the movement feels more intensely to detect if the acceleration suffered has been so strong that exceeded the threshold identified for this particular civil structure. The threshold for each construction is based on the seismic resistant standards and the charge distribution of the building structure. The purpose is to generate an early warning during the occurrence of a seismic event that could be able to prevent people to stay in buildings that may be considered hazardous and that should require an expert evaluation before it could be in use again.

Summary form only given. This proposal describes an innovative approach in the methodologies of post-seismic evaluations of urban zones in Venezuela. It is based on the developing of a platform based on wireless sensor networks, adjusted to the demands of data traffic after an earthquake event, according to the previously identified information needs, assuming that a partial or total collapse of traditional communication services in the disaster area is a real possibility. This work establishes some guidelines for the development of a tool that contributes to the process of identification of potentially affected buildings for an earthquake event. It also describes a proposal for the communication process of the collected data outside the disaster area using the infrastructure of a wireless sensor network and the resources and strengths in telecommunications, available in the Venezuelan Foundation for Seismological Research, without requiring the presence of experts in the event place to perform the first preliminary diagnosis. The proposed system will also help in the decision making process to allocate the available qualified personnel to the structures that really require it for damage evaluation. The incorporation of the wireless sensor technology in the process of post-seismic assessment could be an important management strategy with implications not only in a reduction of the costs associated with the use of equipment and communication technologies, but also in speeding the identification of structures that may be affected by a strong seismic event.