| 1. |
- Sciarretta, A., et al.
(author)
-
A control benchmark on the energy management of a plug-in hybrid electric vehicle
- 2014
-
In: Control Engineering Practice. - : Pergamon Press. - 0967-0661 .- 1873-6939. ; 29, s. 287-298
-
Journal article (peer-reviewed)abstract
- A benchmark control problem was developed for a special session of the IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling (E-COSM 12), held in Rueil-Malmaison, France, in October 2012. The online energy management of a plug-in hybrid-electric vehicle was to be developed by the benchmark participants. The simulator, provided by the benchmark organizers, implements a model of the GM Voltec powertrain. Each solution was evaluated according to several metrics, comprising of energy and fuel economy on two driving profiles unknown to the participants, acceleration and braking performance, computational performance. The nine solutions received are analyzed in terms of the control technique adopted (heuristic rule-based energy management vs. equivalent consumption minimization strategies, ECMS), battery discharge strategy (charge depleting-charge sustaining vs. blended mode), ECMS implementation (vector-based vs. map-based), ways to improve the implementation and improve the computational performance. The solution having achieved the best combined score is compared with a global optimal solution calculated offline using the Pontryagins minimum principle-derived optimization tool HOT.
|
|
| 2. |
- Bergshoeff, E. A., et al.
(author)
-
A consistent limit of 11D Supergravity
- 2023
-
In: Corfu Summer Institute 2022 "School and Workshops on Elementary Particle Physics and Gravity", CORFU 2022. - : Sissa Medialab Srl.
-
Conference paper (peer-reviewed)abstract
- Motivated by old and new developments in non-relativistic string theory, we show that there exists a consistent non-relativistic limit of eleven-dimensional supergravity. Before taking the limit we give a short review of the underlying Membrane Newton-Cartan geometry. This geometry is a particular extension of the Newton-Cartan geometry in the sense that the two nondegenerate metrics of Newton-Cartan geometry (one to measure time intervals and another one to measure spatial distances) are replaced by two nondegenerate metrics of rank 3 and rank 8, respectively. An important role in describing this geometry and in the consistency of the limit is played by the so-called intrinsic torsion tensor components. These are the components of the torsion tensor that are independent of the spin-connection. After expanding the action of eleven-dimensional supergravity as a power series of a contraction parameter, we show how the different divergences that arise when taking the limit can be tamed. We furthermore show how the divergences that arise in expanding the supersymmetry rules can be controlled by imposing a supersymmetric set of constraints. This leads to a Membrane Newton-Cartan supergravity theory where the Newton potential can be identified with the component of the 3-form of eleven-dimensional supergravity that points in the three directions corresponding to the rank 3 degenerate metric.
|
|
| 3. |
- Bergshoeff, E. A., et al.
(author)
-
E10 and gauged maximal supergravity
- 2009
-
In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 2009:1, s. 020 (artno)-
-
Journal article (peer-reviewed)abstract
- We compare the dynamics of maximal three-dimensional gauged supergravity in appropriate truncations with the equations of motion that follow from a one-dimensional E10/K(E-10) coset model at the first few levels. The constant embedding tensor, which describes gauge deformations and also constitutes an M-theoretic degree of freedom beyond eleven-dimensional supergravity, arises naturally as an integration constant of the geodesic model. In a detailed analysis, we find complete agreement at the lowest levels. At higher levels there appear mismatches, as in previous studies. We discuss the origin of these mismatches.
|
|
| 4. |
- Bergshoeff, E. A., et al.
(author)
-
Generalized Newton-Cartan geometries for particles and strings
- 2023
-
In: Classical and quantum gravity. - : IOP Publishing. - 0264-9381 .- 1361-6382. ; 40:7
-
Journal article (peer-reviewed)abstract
- We discuss the generalized Newton-Cartan geometries that can serve as gravitational background fields for particles and strings. In order to enable us to define affine connections that are invariant under all the symmetries of the structure group, we describe torsionful geometries with independent torsion tensors. A characteristic feature of the non-Lorentzian geometries we consider is that some of the torsion tensors are so-called 'intrinsic torsion' tensors. Setting some components of these intrinsic torsion tensors to zero leads to constraints on the geometry. For both particles and strings, we discuss various such constraints that can be imposed consistently with the structure group symmetries. In this way, we reproduce several results in the literature.
|
|
