| 1. |
- Potters, M. G., et al.
(författare)
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Optimal Experiment Design in Closed Loop with Unknown, Nonlinear and Implicit Controllers using Stealth Identification
- 2014
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Ingår i: 2014 European Control Conference, ECC 2014. - : IEEE. - 9783952426913 ; , s. 726-731
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Konferensbidrag (refereegranskat)abstract
- We present a novel optimal experiment design method that is applicable to linear time-invariant systems regulated by unknown, nonlinear and implicitly-defined controllers. Current methods require an explicit expression for the controller in order to construct the optimal excitation spectrum. Consequently, these are limited to linearly-controlled systems. The identification scheme suggested in this paper circumvents the aforementioned requirement by ensuring that the excitation signal remains unnoticed by the controller, i.e., the identification data is gathered in an open-loop fashion. Our theoretical analysis is complemented with a numerical study on a six-parameter, single-input single-output linear system controlled by an MPC. We find that our method generates least-costly excitation signals which deliver identified models that lie close to the true system whilst honoring quality constraints, validating the novel optimal experiment design framework.
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| 2. |
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| 3. |
- Batani, D., et al.
(författare)
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Effects of laser prepulse on proton generation
- 2010
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - : Elsevier BV. - 0168-9002. ; 620:1, s. 76-82
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Konferensbidrag (refereegranskat)abstract
- Low-intensity laser prepulse ( < 10(13) W/cm(2), ns duration) are a major issue in experiments on laser-generation of protons, often limiting the performances of proton sources produced by high-intensity lasers (approximate to 10(19) W/cm(2), ps or fs duration) Several effects are associated to the prepulse and are discussed in this contribution: i) Destruction of thin foil targets by the shock generated by the laser prepulse ii) Creation of preplasma on target front side affecting laser absorption iii) Deformation of target rear side iv) Whole displacement of thin foil targets affecting focusing condition In particular, we show that under oblique high-intensity irradiation and for low prepulse intensities, the proton beam is directed away from the target normal. Deviation is towards the laser forward direction, with an angle that increases with the level and duration of the ASE pedestal. Also, for a given laser pulse, beam deviation increases with proton energy. The observations are discussed in terms of Target Normal Sheath Acceleration, in combination with a laser-controllable shock wave locally deforming the target surface. (C) 2010 Elsevier B.V. All rights reserved.
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| 4. |
- Batani, D., et al.
(författare)
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Effects of laser prepulses on laser-induced proton generation
- 2010
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Ingår i: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Low-intensity laser prepulses (<10(13) W cm(-2), nanosecond duration) are a major issue in experiments on laser-induced generation of protons, often limiting the performances of proton sources produced by high-intensity lasers (approximate to 10(19) W cm(-2), picosecond or femtosecond duration). Depending on the intensity regime, several effects may be associated with the prepulse, some of which are discussed in this paper: (i) destruction of thin foil targets by the shock generated by the laser prepulse; (ii) creation of preplasma on the target front side affecting laser absorption; (iii) deformation of the target rear side; and (iv) whole displacement of thin foil targets affecting the focusing condition. In particular, we show that under oblique high-intensity irradiation and for low prepulse intensities, the proton beam is directed away from the target normal. Deviation is towards the laser forward direction, with an angle that increases with the level and duration of the ASE pedestal. Also, for a given laser pulse, the beam deviation increases with proton energy. The observations are discussed in terms of target normal sheath acceleration, in combination with a laser-controllable shock wave locally deforming the target surface.
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| 7. |
- Kuopanportti, Pekko, et al.
(författare)
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Core sizes and dynamical instabilities of giant vortices in dilute Bose-Einstein condensates
- 2010
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Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - : American Physical Society. - 1050-2947 .- 1094-1622. ; 81:2
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Tidskriftsartikel (refereegranskat)abstract
- Motivated by a recent demonstration of cyclic addition of quantized vorticity into a Bose-Einstein condensate, the vortex pump, we study dynamical instabilities and core sizes of giant vortices. The core size is found to increase roughly as a square-root function of the quantum number of the vortex, whereas the strength of the dynamical instability either saturates to a fairly low value or increases extremely slowly for large quantum numbers. Our studies suggest that giant vortices of very high angular momenta may be achieved by gradually increasing the operation frequency of the vortex pump.
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| 8. |
- Lundh, Anna, et al.
(författare)
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Outcomes of child psychiatric treatment.
- 2013
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Ingår i: Acta psychiatrica Scandinavica. - : Wiley. - 1600-0447 .- 0001-690X. ; 128:1, s. 34-44
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Tidskriftsartikel (refereegranskat)abstract
- Objective The aim of this study was to investigate outcomes of child psychiatric outpatient treatment as usual and to identify outcome predictors, with special regard to attention-deficit/hyperactivity disorder (ADHD), mood disorder, obsessive-compulsive disorder and conduct disorder. Method Routinely collected data from 12613 outpatients between July 2006 and January 2010 in Stockholm, Sweden were analysed. The outcome measure was change in Children's Global Assessment Scale (CGAS) ratings between first visit and case closure (CGAS). Results CGAS improved during the course of treatment across all diagnostic groups, ranging from a mean change of 4 (mental retardation) to 16 (suicide attempts). CGAS was two times higher in the mood disorder group compared with the ADHD group. In the mood disorder group, several psychotherapies were associated with better outcome but not medication. In the ADHD group, psychotherapeutic interventions were also associated with better outcome, but those who received treatment with central stimulants received less non-medical interventions. Conclusion Whereas the functional impairment and the level of improvement in mood disorder corresponded to previous efficacy studies, the ADHD patients were more impaired and improved less after treatment. This should prompt a critical discussion as to whether ADHD patients receive the best available treatment in CAMHS in Stockholm and elsewhere.
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| 9. |
- Lundh, Lars-Gunnar, et al.
(författare)
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Insomnia
- 2011
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Ingår i: Mindfulness and acceptance in behavioral medicine. - 9781572247314 ; , s. 131-158
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Bokkapitel (refereegranskat)
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| 10. |
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