Search results for " drive"
showing 10 items of 286 documents
Modelling of asymmetric nanojets in coronal loops
2021
Context. Observations of reconnection jets in the solar corona are emerging as a possible diagnostic for studying highly elusive coronal heating. Such jets, and in particular those termed nanojets, can be observed in coronal loops and have been linked to nanoflares. However, while models successfully describe the bilateral post-reconnection magnetic slingshot effect that leads to the jets, observations reveal that nanojets are unidirectional or highly asymmetric, with only the jet travelling inward with respect to the coronal loop’s curvature being clearly observed. Aims. The aim of this work is to address the role of the curvature of the coronal loop in the generation and evolution of asym…
Current signature based fault diagnosis of field-oriented and direct torque-controlled induction motor drives
2017
In this article, the operation of three-phase squirrel-cage induction motors is analysed under faulty conditions in closed loop with state-of-the-art controllers, namely, the field-oriented control...
Turtles on the trash track: loggerhead turtles exposed to floating plastic in the Mediterranean Sea
2019
Loggerhead turtles (Caretta caretta) spend most of their life in large marine areas occupying a variety of habitats where they are exposed to different types of threats. Among these, marine litter is known to pose a risk of entanglement or ingestion. Areas of risk exposure can be identified where the species overlap with litter accumulations, but gathering data on this highly mobile species and marine litter, especially in high sea areas, is challenging. Here we analysed five years of sea turtle and marine litter data collected by a network of research bodies along fixed trans-border transects in the Mediterranean Sea. Ferries were used as observation platforms to gather systematic data on …
Temperature Rise Estimation of Induction Motor Drives Based on Loadability Curves to Facilitate Design of Electric Powertrains
2017
Thermal protection limits are equally important as mechanical specifications when designing electric drivetrains. However, properties of motor drives like mass/length of copper winding or heat dissipation factor are not available in producers’ catalogs. The lack of this essential data prevents the effective selection of drivetrain components and makes it necessary to consult critical design decisions with equipment's suppliers. Therefore, in this paper, the popular loadability curves that are available in catalogs become a basis to formulate a method that allows to estimate temperature rise of motor drives. The current technique allows for evaluating a temperature rise of a motor drive for …
MHD free convection in a liquid-metal filled cubic enclosure. II. Internal heating
2002
The buoyancy-driven magnetohydrodynamic flow in a liquid-metal filled cubic enclosure was investigated by three-dimensional numerical simulation. The enclosure was differentially heated at two opposite vertical walls, all other walls being adiabatic, and a uniform magnetic field was applied orthogonal to the temperature gradient and to the gravity vector. The Rayleigh number was 105 and the Prandtl number was 0.0321 (characteristic of Pb–17Li at 573 K). The Hartmann number was made to vary between 102 and 103 and the electrical conductance of the walls between 0 and ∞. The continuity, momentum and enthalpy transport equations, in conjunction with a Poisson equation for the electric potentia…
One-dimensional Mixed MHD Convection
2006
The parallel, fully developed flow of an electrically conducting fluid between plane parallel walls under the simultaneous influence of a driving pressure head, buoyancy, and magnetohydrodynamic (MHD) forces is studied. The fluid is assumed to be internally heated and the flow is modeled as one-dimensional and incompressible, while the Boussinesq approximation is adopted for the buoyancy terms. Analytical solutions are obtained for temperature, velocity and electrical potential under different electrical boundary conditions, forced to natural convection intensity ratios and values of the magnetic induction. Generalized working charts are presented which synthetically describe the system''s …
Dynamic mode decomposition of magnetohydrodynamic bubble chain flow in a rectangular vessel
2021
We demonstrate the first application of dynamic mode decomposition (DMD) to bubble flow with resolved dynamic liquid/gas boundaries. Specifically, we have applied DMD to the output of numerical simulations for a system where chains of bubbles ascend through a rectangular liquid metal vessel. Flow patterns have been investigated in the vessel and bubble reference frames. We show how gas flow rate and applied magnetic affect bubble wake flow and larger-scale flow structures within the liquid metal vessel by examining the velocity field mode statistics over trajectory time and total flow time as well as the computed mode velocity fields. The results of this proof-of-concept study indicate that…
Temporal drivers of liking
2013
Abstract Generally liking is measured overall but is likely to vary over the food intake, like sensory perception. Replacing the attributes in Temporal Dominance of Sensations (TDS) by the categories of a usual ordinal liking scale makes it possible to monitor liking changes while eating a product (Sudre et al., 2012). This methodology allows for a better understanding of the influence of temporal dominance of sensations on liking and liking evolution over the time of product intake. Thus, it is possible to associate hedonic temporal data and descriptive temporal data (TDS profiles), which would identify drivers of liking, that is attributes which, when cited as dominant, would lead to a de…
On the Assessment of Fitness to Drive: Steering and Brake Operative Forces
2021
[EN] The Directive (EU) 2015/653 aimed at facilitating that the maximum force that any disabled driver could make on the vehicle's primary controls could be adjusted to their needs. The technical adjustment in the vehicle's design requires a measurement of the operational forces applied by the driver on the steering and brake controls, in order to determine its functional capacity during the execution of driving maneuvers. The objective of this paper is to define the steering and braking operative forces used for driving current market M1 motor vehicles for the ¿fitness to drive assessment of drivers with physical disabilities. A total of 200 trials were performed with 17 different vehicles…
Developmental Trajectories of Internally and Externally Driven Temporal Prediction.
2015
The ability to generate temporal prediction (TP) is fundamental to our survival since it allows us to selectively orient our attention in time in order to prioritize relevant environmental information. Studies on adult participants showed that externally and internally driven mechanisms can be engaged to establish TP, both resulting in better behavioural performance. However, few studies on children have investigated the ability to engage internally and externally driven TP, especially in relation to how these mechanisms change across development. In this study, 111 participants (88 children between six and eleven years of age, and 23 adults) were tested by means of a simple reaction time p…