Bayesian identification of energy models for industrial machinery controlled rotary axes

2021 ◽  
pp. 128187
Author(s):  
Ettore Lanzarone ◽  
Stefano Borgia
2019 ◽  
Author(s):  
Pier Paolo Poier ◽  
Louis Lagardere ◽  
Jean-Philip Piquemal ◽  
Frank Jensen

<div> <div> <div> <p>We extend the framework for polarizable force fields to include the case where the electrostatic multipoles are not determined by a variational minimization of the electrostatic energy. Such models formally require that the polarization response is calculated for all possible geometrical perturbations in order to obtain the energy gradient required for performing molecular dynamics simulations. </p><div> <div> <div> <p>By making use of a Lagrange formalism, however, this computational demanding task can be re- placed by solving a single equation similar to that for determining the electrostatic variables themselves. Using the recently proposed bond capacity model that describes molecular polarization at the charge-only level, we show that the energy gradient for non-variational energy models with periodic boundary conditions can be calculated with a computational effort similar to that for variational polarization models. The possibility of separating the equation for calculating the electrostatic variables from the energy expression depending on these variables without a large computational penalty provides flexibility in the design of new force fields. </p><div><div><div> </div> </div> </div> <p> </p><div> <div> <div> <p>variables themselves. Using the recently proposed bond capacity model that describes molecular polarization at the charge-only level, we show that the energy gradient for non-variational energy models with periodic boundary conditions can be calculated with a computational effort similar to that for variational polarization models. The possibility of separating the equation for calculating the electrostatic variables from the energy expression depending on these variables without a large computational penalty provides flexibility in the design of new force fields. </p> </div> </div> </div> </div> </div> </div> </div> </div> </div>


Author(s):  
Germán Ramos Ruiz ◽  
Vicente Gutierrez González ◽  
Eva Lucas Segarra ◽  
Germán Campos Gordillo ◽  
Carlos Fernandez Bandera

1977 ◽  
Vol 7 (3) ◽  
pp. 279-292 ◽  
Author(s):  
David J. Edelman
Keyword(s):  

2013 ◽  
Vol 2 (2) ◽  
pp. 158-177 ◽  
Author(s):  
Maurizio Gargiulo ◽  
Brian Ó Gallachóir
Keyword(s):  

RSC Advances ◽  
2021 ◽  
Vol 11 (15) ◽  
pp. 8654-8663
Author(s):  
Fatima Zahra Ramadan ◽  
Flaviano José dos Santos ◽  
Lalla Btissam Drissi ◽  
Samir Lounis

Based on density functional theory combined with low-energy models, we explore the magnetic properties of a hybrid atomic-thick two-dimensional (2D) material made of germanene doped with fluorine atoms in a half-fluorinated configuration (Ge2F).


2021 ◽  
Vol 13 (8) ◽  
pp. 4549
Author(s):  
Sara Salamone ◽  
Basilio Lenzo ◽  
Giovanni Lutzemberger ◽  
Francesco Bucchi ◽  
Luca Sani

In electric vehicles with multiple motors, the torque at each wheel can be controlled independently, offering significant opportunities for enhancing vehicle dynamics behaviour and system efficiency. This paper investigates energy efficient torque distribution strategies for improving the operational efficiency of electric vehicles with multiple motors. The proposed strategies are based on the minimisation of power losses, considering the powertrain efficiency characteristics, and are easily implementable in real-time. A longitudinal dynamics vehicle model is developed in Simulink/Simscape environment, including energy models for the electrical machines, the converter, and the energy storage system. The energy efficient torque distribution strategies are compared with simple distribution schemes under different standardised driving cycles. The effect of the different strategies on the powertrain elements, such as the electric machine and the energy storage system, are analysed. Simulation results show that the optimal torque distribution strategies provide a reduction in energy consumption of up to 5.5% for the case-study vehicle compared to simple distribution strategies, also benefiting the battery state of charge.


2021 ◽  
Vol 112 (11-12) ◽  
pp. 3279-3306
Author(s):  
Paolo Albertelli ◽  
Michele Monno

AbstractManufacturing craves for more sustainable solutions for machining heat-resistant alloys. In this paper, an assessment of different cooling lubrication approaches for Ti6Al4V milling was carried out. Cryogenic cutting (liquid nitrogen) and conventional cooling (oil-based fluid) were assessed with respect to dry cutting. To study the effects of the main relevant process parameters, proper energy models were developed, validated and then used for comparing the analysed cooling lubrication strategies. The model parameters were identified exploiting data from specifically conceived experiments. The power assessment was carried out considering different perspectives, with a bottom-up approach. Indeed, it was found that cryogenic cooling, thanks to a better tribological behaviour, is less energy demanding (at least 25%) than dry and conventional cutting. If the spindle power is considered, lower saving percentages can be expected. Cryogenic cooling showed its best energy performance (from 3 to 11 times) with respect to conventional cutting if the machine tool perspective is analysed. Considering even the primary energy required for producing the cutting fluids, the assessment showed that cryogenic cooling requires up to 19 times the energy required for conventional cutting.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1187
Author(s):  
Vicente Gutiérrez González ◽  
Germán Ramos Ruiz ◽  
Carlos Fernández Bandera

The need to reduce energy consumption in buildings is an urgent task. Increasing the use of calibrated building energy models (BEM) could accelerate this need. The calibration process of these models is a highly under-determined problem that normally yields multiple solutions. Among the uncertainties of calibration, the weather file has a primary position. The objective of this paper is to provide a methodology for selecting the optimal weather file when an on-site weather station with local sensors is available and what is the alternative option when it is not and a mathematically evaluation has to be done with sensors from nearby stations (third-party providers). We provide a quality assessment of models based on the Coefficient of Variation of the Root Mean Square Error (CV(RMSE)) and the Square Pearson Correlation Coefficient (R2). The research was developed on a control experiment conducted by Annex 58 and a previous calibration study. This is based on the results obtained with the study case based on the data provided by their N2 house.


Universe ◽  
2021 ◽  
Vol 7 (6) ◽  
pp. 163
Author(s):  
Verónica Motta ◽  
Miguel A. García-Aspeitia ◽  
Alberto Hernández-Almada ◽  
Juan Magaña ◽  
Tomás Verdugo

The accelerated expansion of the Universe is one of the main discoveries of the past decades, indicating the presence of an unknown component: the dark energy. Evidence of its presence is being gathered by a succession of observational experiments with increasing precision in its measurements. However, the most accepted model for explaining the dynamic of our Universe, the so-called Lambda cold dark matter, faces several problems related to the nature of such energy component. This has led to a growing exploration of alternative models attempting to solve those drawbacks. In this review, we briefly summarize the characteristics of a (non-exhaustive) list of dark energy models as well as some of the most used cosmological samples. Next, we discuss how to constrain each model’s parameters using observational data. Finally, we summarize the status of dark energy modeling.


Sign in / Sign up

Export Citation Format

Share Document