Improving the performance of a stability monitoring system by adding wave encounter frequency estimation

[Abstract]: Onboard guidance systems have emerged to improve the safety of fishing vessels providing the skipper with simplified stability information. In the last years, the authors have developed a stability monitoring system that automatically estimates the natural roll frequency of the vessel. Although the performance was acceptable, there were some specific situations where the influence of external excitations reduced the accuracy of the stability estimations. In this work, a methodology to automatically estimate the wave encounter frequency from ship motions is proposed. Then, this methodology is included in the stability monitoring system. Towing tank tests of a mid-sized stern trawler in different conditions have been used to analyse the improvements obtained with this approach.Xunta de Galicia; ED431C 2021/3

Atmospheric Temperature Effect in secondary cosmic rays observed with a two square meter ground-based detector

A high resolution 2 m$^2$ tracking detector, based on timing Resistive Plate Chamber (tRPC) cells, has been installed at the Faculty of Physics of the University of Santiago de Compostela (Spain) in order to improve our understanding of the cosmic rays arriving at the Earth's surface. Following a short commisioning of the detector, a study of the atmospheric temperature effect of the secondary cosmic ray component was carried out. A method based on Principal Component Analysis (PCA) has been implemented in order to obtain the distribution of temperature coefficients, $W_T(h)$, using as input the measured rate of nearly vertical cosmic ray tracks, showing good agreement with the theoretical expectation. The method succesfully removes the correlation present between the different atmospheric layers, that would be dominant otherwise. We briefly describe the initial calibration and pressure correction procedures, essential to isolate the temperature effect. Overall, the measured cosmic ray rate displays the expected anticorrelation with the effective atmospheric temperature, through the coefficient $\alpha_T= -0.279 \pm 0.051$ \%/K. Rates follow the seasonal variations, and unusual short-term events are clearly identified too.Comment: 18 pages, 10 figures, Submitted to Earth and Space Scienc

The role of lichenized algae in the production of Cladonia verticillaris depsidones, revealed by using alginate-immobilized cells

The mycobiont of the lichen Cladonia verticillaris produces two depsidones, protocetraric and fumarprotocetraric acids, in the nature. This last compound is produced from the former depsidone. To study the role of the algal partner in the production of these depsidones in the lichen thallus, fungal and algal partners were separated and immobilized in calcium alginate. The fungal immobilizates, as lichenized or isolated mycobiont, produced both depsidones, preferently fumarporotocetraric acid from acetate as a precursor. However, when algal immobilizates were co-incubated on acetate with the fungal ones, protocetraric acid was over-produced during the first 11 days of incubation to be later converted into fumarprotocetraric acid. We hypothesized about the algal production of a diffusible metabolite that inhibits the transformation of a depsidone into the other one

Kinematic analysis and dimensional optimization of a 2R2T parallel manipulator

International audienceThe need of a device providing two translational (2T) and two rotational (2R) movements led us to the design a 3UPS-1RPU parallel manipulator. The manipulator consisted on a mobile platform connected to a base through four legs. That is, the manipulator layout has one central leg and three external legs at the same radial distance. By studying different locations of the legs anchoring point, we improved the first layout design, yet not the optimal one. On this basis, this paper focus on the optimal dimensional design of the manipulator. To this end, we put forward the kinematics equations of the manipulator in accordance to the anchoring points coordinates. Through a numerical approach, the equations enable to find the manipulator workspace. Also, we find a global manipulability index using a local dexterity measure. The latter index serves as optimal function. The optimization process considers joint constraints. Thus, we built a nonlinear optimization problem solved through sequential quadratic programming algorithms. We start by optimizing only a small set of parameters rather than the entire set, which gives us insights on the initial guess to optimize using the entire set. The optimal design layout varies from the original layout. Findings suggest that a task-oriented reconfiguration strategy can improve manipulator performance

Extending the cascading by pairs of multiport generalised scattering matrices for characterizing the connected ports

An extension to the traditional technique for cascading generalized scattering matrices (GSMs) by pairs is presented. It can solve the connection of an arbitrary number of networks, with an arbitrary number of ports, while being quite intuitive and easy to implement. It is able to compute, not only the response at the free ports of the global network -like the traditional cascading-by-pairs does- but also the connected ports, obtaining an extended GSM (eGSM), which can be used to find the field inside the full network for an arbitrary incidence.Díaz Caballero, E.; Belenguer, A.; Esteban González, H.; Boria Esbert, VE. (2014). Extending the cascading by pairs of multiport generalised scattering matrices for characterizing the connected ports. IEEE Microwave and Wireless Components Letters. 24(11):733-735. doi:10.1109/LMWC.2014.2348181S733735241

Caracterización de las áreas urbanas gallegas en función de los flujos de movilidad obligada

La realidad territorial en los municipios gallegos evolucionó a ritmos dispares, afectados por dinámicas muy diferentes en cada uno de los casos. Los problemas en la aplicación de la normativa urbanística y de los instrumentos técnicos para la gestión del suelo gestaron unos ámbitos urbanos desconectados de su realidad metropolitana. Las áreas de influencia en las ciudades de Galicia presentan modelos complejos, adaptados a las dificultades que les privaron de una gestión prudente y coherente de los nuevos territorios urbanos. En la evaluación de la nueva realidad urbana, de sus condiciones y características, la movilidad residencial y la recurrente diaria es un elemento de primer rango de análisis. La escala adquirida por el proceso de urbanización es fruto de estos comportamientos en lo referente a la movilidad. Esta se ha intensificado en los últimos años y muestra de modo claro cuáles son las dinámicas funcionales reales, necesitadas de una nueva y urgente organización y gobernanza territoriales.Territorial reality in Galician municipalities evolved to different rhythms, affected by very different dynamics in each one of the cases. The problems in the application of the town-planning and technical instruments for land management provoked the disconnection between cities and their metropolitan nature. Areas of influence in Galician cities present complex models, adapted to the difficulties which deprived them from a prudent and coherent management of the new urban territories. In the assessment of the new urban reality, its conditions and characteristics, residential mobility is a key issue of analysis. The scale of the process of urbanization is a result of these behaviours with regard to mobility. In fact, mobility has intensified in the last years and clearly shows real functional dynamics, needing a new and urgent territorial organization and governance

A highly enantioselective abiotic receptor for malate dianion in aqueous solution

The highly enantioselective molecular recognition of the malate dianion by a synthetic receptor in aqueous solution has been studied by potentiometric titrations, mass spectrometry (ESI-MS), diffusion measurements (PGSE NMR) and molecular modeling.Garcia-España Monsonis, Enrique, [email protected]

Las necesidades del alumnado de Magisterio de Lengua Extranjera y Educación Física en torno a las Nuevas Tecnologías

The incorporation of the new technologies to the curriculum of the title of teacher has presented throughout their advantages development and inconvenient that they have gone dialing their path. This circumstance has caused that us, as educational of the same we see ourselves in the need of determining which are the knowledge that the pupils that study it already possess, what believe what are and what do not know of they. In this article are presented the results obtained in connection with these problems in two specialties from the title of Teacher, Foreign language and Physical Education, during the academic course 2003/2004.La incorporación de las nuevas tecnologías al curriculum de la titulación de maestro ha presentado a lo largo de su desarrollo ventajas e inconvenientes que han ido marcando su trayectoria. Esta circunstancia nos ha hecho que, como docentes de la misma nos veamos en la necesidad de determinar cuáles son los conocimientos que los alumnos que la cursan ya poseen, qué creen que son y qué desconocen de ellas. En este artículo se presentan los resultados obtenidos en torno a estas cuestiones en dos especialidades de la titulación de Maestro, Lengua Extranjera y Educación Fisica, durante el curso académico 2003/2004

Tag shedding estimation in Palinurus elephas (Fabricius, 1787)

In this paper a numerical method for tag shedding calculation from double tagging data was used to estimate the tag loss rate in Palinurus elephas from capture-mark-recapture experiments. Four consecutive experimental surveys during years 1999-2002 inside the Columbretes islands marine reserve (CIMR) were carried out and the captured spiny lobsters were dorso-laterally double-tagged with T-bar anchor tags on both sides between the first and second abdominal segments. The recaptures during the following years (2000-2008) were recorded and the evolution of the proportion of single- and double-tagged specimens was analysed. The immediate tag loss produced after tagging could not be accurately modelled, but in view of the results is believed to be low. The probability of tag loss per year was estimated in 6% (sexes combined). The factors causing this tag loss and the repercussion of this rates of shedding on further studies are examine

Double tagging experiments and tag loss in Palinurus elephas

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