Search results for "LOAD"
showing 10 items of 1967 documents
Development of a Fractional PI controller in an FPGA environment for a Robust High-Performance PMSM Electrical Drive
2021
This paper proposes the application of a Fractional Order PI (FOPI) in the speed loop of a high performance PMSM drive to obtain both speed tracking and load rejection performance with a 1-DOF Proportional Integral (PI) controller and 2-DOF Integral Proportional (IP) controller. Hardware validation was implemented in Field Programmable Gate Array on the LabVIEW environment, based on the National Instruments System-on-Module sbRIO-9651 with Xilinx Zynq-7020. Simulation and experimental results are presented to comparing the performance of a PI, IP and FOPI controllers in the speed loop of a Field Oriented Control (FOC) of a Permanent Magnet Synchronous Motor (PMSM).
The FLuorescence EXplorer Mission Concept-ESA's Earth Explorer 8
2017
In November 2015, the FLuorescence EXplorer (FLEX) was selected as the eighth Earth Explorer mission of the European Space Agency. The tandem mission concept will provide measurements at a spectral and spatial resolution enabling the retrieval and interpretation of the full chlorophyll fluorescence spectrum emitted by the terrestrial vegetation. This paper provides a mission concept overview of the scientific goals, the key objectives related to fluorescence, and the requirements guaranteeing the fitness for purpose of the resulting scientific data set. We present the mission design at the time of selection, i.e., at the end of project phase Phase A/B1, as developed by two independent indus…
Vehicle routing problems with drones equipped with multi-package payload compartments
2022
The vehicle routing problem with drones (VRP-D) consists of designing combined truck-drone routes and schedules to serve a set of customers with specific requests and time constraints. In this paper, VRP-D is extended to include a fleet of drones equipped with multi-package payload compartments to serve more customers on a single trip. Moreover, a drone can return to a truck, different from the one from which it started, to swap its depleted battery and/or to pick up more packages. This problem, denoted as VRP-D equipped with multi-package payload compartments (VRP-D-MC), aims to maximize total profit. In this work, an adaptive multi-start simulated annealing (AMS-SA) metaheuristic algorith…
Energy-Efficient Edge Computing Service Provisioning for Vehicular Networks: A Consensus ADMM Approach
2019
In vehicular networks, in-vehicle user equipment (UE) with limited battery capacity can achieve opportunistic energy saving by offloading energy-hungry workloads to vehicular edge computing nodes via vehicle-to-infrastructure links. However, how to determine the optimal portion of workload to be offloaded based on the dynamic states of energy consumption and latency in local computing, data transmission, workload execution and handover, is still an open issue. In this paper, we study the energy-efficient workload offloading problem and propose a low-complexity distributed solution based on consensus alternating direction method of multipliers. By incorporating a set of local variables for e…
Analytical performance issues: comparison of ATP bioluminescence and aerobic bacterial count for evaluating surface cleanliness in an Italian hospita…
2013
Contaminated hospital surfaces have been demonstrated to be an important environmental reservoir of microorganisms that can increase the risk of nosocomial infection in exposed patients. As a consequence, cleaning and disinfecting hospital environments play an important role among strategies for preventing healthcare-associated colonization and infections. The aim of the present study was to evaluate whether adenosine triphosphate (ATP) presence, measured by bioluminescence methods, can predict microbiological contamination of hospital surfaces. The study was carried out between September and December 2012 at the University Hospital “P. Giaccone” of Palermo. A total of 193 randomly selected…
Modification of the immune response against hepatitis B virus by the human immunodeficiency virus.
1989
Hepatitis B virus and the human immunodeficiency virus are similarly transmitted. Individuals with preexisting HIV infection have a higher chance to become HBsAg carriers than do anti-HIV negative persons. Cytotoxic T cells with specificity for HBcAg, that are under the control of HBcAg-specific helper T cells, are responsible for liver injury. There is good evidence that HIV infection lowers inflammatory activity, is associated with milder liver histology, high levels of viral replication and low seroconversion rates. In addition interferon alpha therapy is less effective in anti-HIV positive subjects. The immune response against HBsAg is helper T-cell dependent and vaccination against hep…
Valoración de la Ecología de Aprendizaje Autorregulado Virtualizada para la Didáctica de las Ciencias de la Naturaleza durante la crisis COVID-19
2021
Los modelos de enseñanza-aprendizaje universitarios están siendo afectados por la crisis originada por la COVID-19. Para atender a esta crisis desencadenada se diseñó de urgencia una propuesta de ecología de aprendizaje autorregulado virtualizada durante el confinamiento de 2020 en la asignatura de Ciencias de la Naturaleza y su Didáctica I del Grado en Maestro de Educación Primaria. En este artículo se describe esta ecología de aprendizaje: los materiales elaborados, los contextos diseñados y la utilización de estrategias de enseñanza-aprendizaje basadas en el aprendizaje autorregulado, tanto durante la docencia virtual como durante la tutorización del alumnado. El objetivo de este estudio…
An Aircraft Pilot Workload Sensing System
2021
The workload evaluation is of great importance for human error avoidance training, particularly in the use of complex systems that requires different and concurrent activities. The excessive workload harms human performance even with adverse outcomes. In the aviation field, certain flight maneuvers, such as take-off and landing, are characterized by great attention and workload demand to the pilot. Thus, a system capable of measuring pilots’ workload levels during flight could be beneficial to increase pilots’ performance. This work aims to study the initial feasibility of a device called Cockpit Pilot Warning System that monitors the pilot workload level during flight. With this aim, an ex…
A further exploration of a nucleophilicity index based on the gas-phase ionization potentials
2008
An empirical nucleophilicity index based on the gas-phase ionization potentials has been recently shown to be useful categorizing and settling the nucleophilicity power of a series of captodative ethylenes reacting in cycloaddition reactions (L.R. Domingo, E. Chamorro, P. Perez, Journal of Organic Chemistry 73 (2008) 4615–4624). In the present work, the applicability of such model is tested within a broader series of substituted alkenes, substituted aromatic compounds and simple nucleophilic molecules. This index obtained within a Koopman’s theorem framework has been evaluated here in both gas and solution phases for several well-known nucleophiles. These results are found to be linearly co…
On the mechanisms involved in the tensile strength of a dissimilar Ti6Al4V/316L laser welded assembly
2021
International audience; The aim of the present work is to analyze the thermomechanical behavior of dissimilar laser seams by means of FE modeling. The case of a Ti6Al4V/316L assembly with vanadium insert was considered. Effective mechanical properties of the main materials and cords were first estimated from NHT measurements. Modeling of the double pass laser welding process was performed first by considering shrinking of the two weld seams during manufacturing, to get the residual stress state in the welded assembly. Modeling of the tensile test was performed in a second step to study the assembly behavior during loading. In these modeling results, the mesh was the cross-section of the mic…