3 known landmarks are enough for solving planar bearing SLAM and fully reconstruct unknown inputs

In this paper we show that for an observer moving in the plane with no other information than the measurement of relative bearing to three known landmarks, it is possible to completely reconstruct its position and velocity. In particular this applies to the case where no model of the vehicle, nor odometry or acceleration measurements are available. Furthermore, in the same hypotheses, the position of any further landmark can be reconstructed from its bearing only. These results are more general than what is currently known on nonlinear observability of the SLAM problem, which relies on known observer velocities. Our results are also more general than the 2D version of known structure-from-motion observability results, which assume unknown but constant velocities. The proposed method is used to build a nonlinear observer directly applicable to a range of problems from computer vision to autonomous visual navigation

Whither European diplomacy? Long-term trends and the impact of the Lisbon Treaty

The article analyses the evolution of European diplomacy over two decades, to assess the impact of the European External Action Service (EEAS) creation alongside consecutive waves of enlargement. Data is drawn from two original datasets about European Union (EU) member states' diplomatic representations within the EU and across the globe. It shows that member states have maintained and strengthened their substantial diplomatic footprint across the EU's territory, expanding it to include new members and making Brussels a diplomatic hub also for non-member countries. In parallel, and despite the establishment of the EEAS, member states have maintained and even increased their networks of diplomatic representations across the globe, alongside more numerous and more politically active EU Delegations (EUDs). At the same time, member states have been reducing their diplomats' numbers, as the cases of Austria, France, Germany and Italy show. This delicate balancing act has been made possible not only by contemporary technological developments, but also by European cooperation, as in the case of EUDs hosting member states' representations in non-member countries, a development referred to as co-location. Therefore, whereas the continued presence of national embassies on the ground could be interpreted as detracting from the EEAS, the existence of EUDs contributes also to other, more indirect but certainly novel, forms of diplomatic cooperation under a single European roof.History and International Relation

A robust iterative learning control for continuous-time nonlinear systems with disturbances

In this paper, we study the trajectory tracking problem using iterative learning control for continuous-time nonlinear systems with a generic fixed relative degree in the presence of disturbances. This class of controllers iteratively refine the control input relying on the tracking error of the previous trials and some properly tuned learning gains. Sufficient conditions on these gains guarantee the monotonic convergence of the iterative process. However, the choice of the gains is heuristically hand-tuned given an approximated system model and no information on the disturbances. Thus, in the cases of inaccurate knowledge of the model or iteration-varying measurement errors, external disturbances, and delays, the convergence condition is unlikely to be verified at every iteration. To overcome this issue, we propose a robust convergence condition, which ensures the applicability of the pure feedforward control even if other classical conditions are not fulfilled for some trials due to the presence of disturbances. Furthermore, we quantify the upper bound of the nonrepetitive disturbance that the iterative algorithm is able to handle. Finally, we validate the convergence condition simulating the dynamics of a two degrees of freedom underactuated arm with elastic joints, where one is active, and the other is passive, and a Franka Emika Panda manipulator

Volatile profiling of Arnicão (Lychnophora salicifolia), a wild medicinal species from Brazilian Cerrado.

Poster 110. SBOE 2015

Adulteration of essential oils: A multitask issue for quality control. three case studies: Lavandula angustifolia mill., Citrus limon (l.) Osbeck and Melaleuca alternifolia (Maiden & Betche) Cheel

The quality control of essential oils (EO) principally aims at revealing the presence of adulterations and at quantifying compounds that are limited by law by evaluating EO chemical compositions, usually in terms of the normalised relative abundance of selected markers, for comparison to reference values reported in pharmacopoeias and/or international norms. Common adulterations of EO consist of the addition of cheaper EO or synthetic materials. This adulteration can be detected by calculating the percent normalised areas of selected markers or the enantiomeric composition of chiral components. The dilution of the EO with vegetable oils is another type of adulteration. This adulteration is quite devious, as it modifies neither the qualitative composition of the resulting EO nor the marker’s normalised percentage abundance, which is no longer diagnostic, and an absolute quantitative analysis is required. This study aims at verifying the application of the two above approaches (i.e., normalised relative abundance and absolute quantitation) to detect EO adulterations, with examples involving selected commercial EO (lavender, bergamot and tea tree) adulterated with synthetic components, EO of different origin and lower economical values and heavy vegetable oils. The results show that absolute quantitation is necessary to highlight adulteration with heavy vegetable oils, providing that a reference quantitative profile is available