A Two-Stage Approach for Routing Multiple Unmanned Aerial Vehicles with Stochastic Fuel Consumption

The past decade has seen a substantial increase in the use of small unmanned aerial vehicles (UAVs) in both civil and military applications. This article addresses an important aspect of refueling in the context of routing multiple small UAVs to complete a surveillance or data collection mission. Specifically, this article formulates a multiple-UAV routing problem with the refueling constraint of minimizing the overall fuel consumption for all of the vehicles as a two-stage stochastic optimization problem with uncertainty associated with the fuel consumption of each vehicle. The two-stage model allows for the application of sample average approximation (SAA). Although the SAA solution asymptotically converges to the optimal solution for the two-stage model, the SAA run time can be prohibitive for medium- and large-scale test instances. Hence, we develop a tabu-search-based heuristic that exploits the model structure while considering the uncertainty in fuel consumption. Extensive computational experiments corroborate the benefits of the two-stage model compared to a deterministic model and the effectiveness of the heuristic for obtaining high-quality solutions.Comment: 18 page

Performance Limits and Geometric Properties of Array Localization

Location-aware networks are of great importance and interest in both civil and military applications. This paper determines the localization accuracy of an agent, which is equipped with an antenna array and localizes itself using wireless measurements with anchor nodes, in a far-field environment. In view of the Cram\'er-Rao bound, we first derive the localization information for static scenarios and demonstrate that such information is a weighed sum of Fisher information matrices from each anchor-antenna measurement pair. Each matrix can be further decomposed into two parts: a distance part with intensity proportional to the squared baseband effective bandwidth of the transmitted signal and a direction part with intensity associated with the normalized anchor-antenna visual angle. Moreover, in dynamic scenarios, we show that the Doppler shift contributes additional direction information, with intensity determined by the agent velocity and the root mean squared time duration of the transmitted signal. In addition, two measures are proposed to evaluate the localization performance of wireless networks with different anchor-agent and array-antenna geometries, and both formulae and simulations are provided for typical anchor deployments and antenna arrays.Comment: to appear in IEEE Transactions on Information Theor

Securing a wireless sensor network for human tracking: a review of solutions

Currently, wireless sensor networks (WSNs) are formed by devices with limited resources and limited power energy availability. Thanks to their cost effectiveness, flexibility, and ease of deployment, wireless sensor networks have been applied to many scenarios such as industrial, civil, and military applications. For many applications, security is a primary issue, but this produces an extra energy cost. Thus, in real applications, a trade-off is required between the security level and energy consumption. This paper evaluates different security schemes applied to human tracking applications, based on a real-case scenario.Junta de Andalucía P07-TIC-02476Junta de Andalucía TIC-570

A Novel PUF-Based Encryption Protocol for Embedded System On Chip

This paper presents a novel security mechanism for sensitive data stored, acquired or processed by a complex electronic circuit implemented as System-on-Chip (SoC) on an FPGA reconfigurable device. Such circuits are increasingly used in embedded or cyber systems employed in civil and military applications. Managing security in the overarching SoC presents a challenge as part of the process of securing such systems. The proposed new method is based on encrypted and authenticated communications between the microprocessor cores, FPGA fabric and peripherals inside the SoC. The encryption resides in a key generated with Physically Unclonable Function (PUF) circuits and a pseudorandom generator. The conceptual design of the security circuit was validated through hardware implementation, testing and analysis of results

An Ambitious Agenda or Big Words? Developing a European Approach to AI. Egmont Security Policy Brief No. 117, November 2019

Artificial Intelligence (AI) has become a key area of global strategic competition, offering potentially revolutionary solutions for commercial, civil, and military applications. While the European Union (EU) has recently taken action as regards the AI’s disruptive potential, it arguably lags in its funding, research, and innovation as compared to the United States or China. Recent policy and funding initiatives at the EU level are shaping a distinctive approach to tackle such challenges, both via increased financing opportunities to address research and innovation gaps and through preventive governance mechanisms for the AI’s responsible technological design and uses. The question remains whether these actions will mitigate the European governance and funding gaps in this emerging technological domain and foster a globally competitive European AI ecosystem

Verification of the quality of dgps signal in Rio Grande do Sul – Brazil, compared to Villarrobledo (Spain)

The GNSS (Global Navigation Satellite System) provides georeferenced data for many civil and military applications. Since the removal of noise in the USGPS signal in 2000, civil applications have exploded and correction methodologies have greatly improved the quality of data without additional cost. DGPS make profit of geostationary signal in order to decrease the error level from metric to sub metric range; however such decrease strongly depends upon local circumstances. In this paper we compare the quality of DGPS signal under very dissimilar conditions: North vs South hemisphere, various geoides (ED50 vs WGS84) and distance to the geostationary satellite among others. The data have been acquired during several seasons according, all of them in vine crops (permanent crop and therefore of known position) which allows to easily address the quality of the georeferenced position

Dynamic cluster head routing protocol in wireless sensor network

Wireless distributed based microsensor systems will have reliable monitoring in variety of environments for both civil and military applications. In this research work, we look at communication protocols, which can have significant impact on the overall energy dissipation of the networks in these systems. Based on the findings that the conventional protocols of direct transmission, minimum-transmission-energy, multihop routing, and static clustering may not be optimal for sensor networks.Therefore we propose DCHRP (Dynamic Cluster Routing Protocol), a cluster-based protocol that utilizes instance cluster creation to evenly distribute the energy load among the sensors in the network. DCHRP uses instance clusters to enable scalability and strength for dynamic networks. In addition to this, DCHRP is able to reduce the energy wastage evenly among the sensors, and allowing easy dynamicity in WSNs