Search results for "ALMA"

Automatic EKF tuning for UAS path following in turbulent air

2018

By using two simultaneously working Extended Kalman Filters, a procedure is implemented in order to perform in a fully autonomous way the path following in turbulent air. To guarantee the robustness of the proposed algorithm, an automatic tuning procedure is proposed to determine optimal values of Process and Measurement Noise statistics. Such a procedure is based on both the characteristics of the disturbances and the desired flight path; in particular, a specific performance index is applied to tune filters. In this way control laws are adapted to the flight condition and these lead to an optimal path-following. This research represents an upload of previous papers. It allows eliminating …

Privilegios y franquezas de la muy noble, muy leal y Felicisima Ciudad de Almansa : confirmados por el rey ... Carlos Quarto.

1790

Iterative altitude-aiding algorithm for improved GNSS positioning

2011

The system proposed in this study relies on a WAVE P2P network, which is a proper standard to fit the vehicular environment wireless communications requests. Starting from the chance to exchange information given by this infrastructure, the possibility to improve the performance of a global navigation satellite system (GNSS) receiver based on a Kalman filter is considered. This improvement is obtained exploiting the external altitude measurements provided by other peers in the network, equipped with GNSS receivers. The topic of an altitude-aided system has been described in a previous work, that highlighted the need for a parameter that points out the effectiveness and the consistency of th…

An Indoor and Outdoor Navigation System for Visually Impaired People

2019

In this paper, we present a system that allows visually impaired people to autonomously navigate in an unknown indoor and outdoor environment. The system, explicitly designed for low vision people, can be generalized to other users in an easy way. We assume that special landmarks are posed for helping the users in the localization of pre-defined paths. Our novel approach exploits the use of both the inertial sensors and the camera integrated into the smartphone as sensors. Such a navigation system can also provide direction estimates to the tracking system to the users. The success of out approach is proved both through experimental tests performed in controlled indoor environments and in r…

Morphological studies in canine (Dalmatian) neuronal ceroid-lipofuscinosis.

1988

Dalmatian dogs may develop a neuronal or generalized ceroid-lipofuscinosis (NCL) which strongly resembles that seen in English setters, especially as to the ultrastructural changes and ubiquity of the stored lipopigments and the retinal pathology, while differing clinically from the disorder of English setters in that the disease has a longer course of up to 5 or 6 yr. Clinical onset is at about age 6 months; however, an unequivocal morphological diagnosis is possible between the 4th and 5th month of life in biopsied skin. Detailed data of additional investigations are in progress and are awaiting later publication. Thus, NCL in the Dalmatian dog, though not yet as thoroughly investigated a…

Batalla que dieron las armas del Rey nuestro señor, y las de su Magestad christianissima, mandadas por el señor Mariscal de Bervik, en el Campo de Al…

Precedeix al tít.: ✠ Filets Text a 1 col. - Reclams Sign.: [ ]2

Hidden oscillations in nonlinear control systems

2011

Abstract The method of harmonic linearization, numerical methods, and the applied bifurcation theory together discover new opportunities for analysis of hidden oscillations of control systems. In the present paper new analytical-numerical algorithm for hidden oscillation localization is discussed. Counterexamples construction to Aizerman's conjecture and Kalman's conjecture on absolute stability of control systems are considered.

Materiality and compositorial errors of a poetical incunabulum: the contribution of textual criticism

2019

L’anàlisi material dels testimonis d’una obra literària forma part de la fase de recensio en un procés de crítica textual, que ha d’anar més enllà de la mera descripció del continent. Cal atendre a la informació que donen aquestes característiques quant als continguts, quant al procés de transmissió dels textos, perquè aquestes dades tindran funcionalitat ecdòtica. Així, aquest treball estudia la materialitat i els errors d’un incunable poètic valencià, que és el primer d’una trilogía d’impresos dedicats a la Immaculada Concepció i patrocinats per Ferran Dies. The material analysis of the witnesses of a literary work is part of the phase of recension in a process of textual criticism, which…

Hybrid nonlinear observer for Inertial Navigation

2016

This paper considers the problem of designing an observer for navigation and localization of inertial systems. Since the measurement systems used in this field have a low update rate with respect to the control algorithm, the design of a suitable observer with sampled measurements is required. Here a hybrid non-linear observer is proposed, combining two different observers with different characteristics. A theoretical treatment is given in order to prove the convergence of the observer and it will be contextualized in the framework of the hybrid systems, providing an elegant setting for the proposed solution. Finally experimental results show the feasibility of the proposed observer and the…

Extended complex Kalman filter for sensorless control of an induction motor

2014

Abstract This paper deals with the design of an extended complex Kalman filter (ECKF) for estimating the state of an induction motor (IM) model, and for sensorless control of systems employing this type of motor as an actuator. A complex-valued model is adopted that simultaneously allows a simpler observability analysis of the system and a more effective state estimation. The observability analysis of this model is first performed by assuming that a third order ECKF has to be designed, by neglecting the mechanical equation of the IM model, which is a valid hypothesis when the motor is operated at constant rotor speed. It is shown that this analysis is more effective and easier than the one …