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1 – 5 of 5The aim of this paper is to propose and analyse policies capable of generating left‐skewed pension distributions. Such policies can deliver large pension values with high…
Abstract
Purpose
The aim of this paper is to propose and analyse policies capable of generating left‐skewed pension distributions. Such policies can deliver large pension values with high probability and hence are of interest to practical fund managers.
Design/methodology/approach
The paper uses a computational method capable of solving stochastic optimal control problems. The optimal strategies obtained through the method are used to simulate dynamic portfolio management.
Findings
The paper finds that optimisation of locally non‐concave performance measures has produced left‐skewed payoff distributions of small VaR and CVaR. The distributions remain left‐skewed for relatively large values of the diffusion parameter.
Practical implications
On the basis of the findings, it would seem beneficial for real‐world fund managers to implement this kind of optimising “cautious‐relaxed” policy.
Originality/value
A novel non‐concave performance measure has been proposed in the paper to describe a portfolio manager's aim. The computed “cautious‐relaxed” policies have been shown to realise this aim.
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Tomasz Rogalski, Paweł Rzucidło, Stanisław Noga and Jacek Prusik
The purpose of this paper is to present the idea of automatic flight control algorithms capable of performing an Immelmann turn manoeuvre automatically. This is a case of a…
Abstract
Purpose
The purpose of this paper is to present the idea of automatic flight control algorithms capable of performing an Immelmann turn manoeuvre automatically. This is a case of a manoeuvre far removed from so-called standard flight. The character of this manoeuvre and the range of changes in the aircraft flight parameters restrict the application of standard control algorithms. Furthermore, the possibility of acquiring full and detailed information about the aircraft’s flight parameters is limited in such cases. This paper seeks to analyse an alternative solution that can be applied in some specific cases.
Design/methodology/approach
This paper uses theoretical discussion and breakdowns to create the basics for development of structures of control algorithms. A simplified analytical approach was applied to tune regulators and the results of the research were verified in a series of software-in-the loop computer simulations.
Findings
The structure of the control system enabling aerobatic flight (with the Immelmann turn as the selected example) was identified and the method for tuning the regulators is also presented.
Practical implications
It could serve as a foundation for autopilots working in non-conventional flight states and aircraft automatic recovery systems.
Originality/value
This paper presents the author’s original approach to aircraft automatic control when high control precision is not the priority and not all flight parameters can be precisely measured.
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Keywords
Tomasz Rogalski, Paweł Rzucidło and Jacek Prusik
The paper aims to present an idea of automatic control algorithms dedicated to both small manned and unmanned aircraft, capable to perform spin maneuver automatically. This is a…
Abstract
Purpose
The paper aims to present an idea of automatic control algorithms dedicated to both small manned and unmanned aircraft, capable to perform spin maneuver automatically. This is a case of maneuver far away from so-called standard flight. The character of this maneuver and the range of aircraft flight parameters changes restrict application of standard control algorithms. Possibility of acquisition full information about aircraft flight parameters is limited as well in such cases. This paper analyses an alternative solution that can be applied in some specific cases.
Design/methodology/approach
The paper uses theoretical discussion and breakdowns to create basics for development of structures of control algorithms. Simplified analytical approach was applied to tune regulators. Results of research were verified in series of software-in-the loop, computer simulations.
Findings
The structure of the control system enabling aerobatic flight (spin flight as example selected) was found and the method how to tune regulators was presented as well.
Practical implications
It could be a fundament for autopilots working in non-conventional flight states and aircraft automatic recovery systems.
Originality/value
The paper presents author’s original approach to aircraft automatic control when high control precision is not the priority, and not all flight parameters can be precisely measured.
Details
Keywords
Bartosz Sawicki, Jacek Starzyński, Stanisław Wincenciak, Andrzej Krawczyk and Mladen Trlep
Arthritis, the illness of the bones, is one of the diseases which especially attack the knee joint. Magnetic stimulation is a very promising treatment, although not very clear as…
Abstract
Arthritis, the illness of the bones, is one of the diseases which especially attack the knee joint. Magnetic stimulation is a very promising treatment, although not very clear as to its physical background. Deals with the mathematical simulation of the therapeutical technique, i.e. the magnetic stimulation method. Considers the low‐frequency magnetic field. To consider eddy currents one uses the pair of potentials: electric vector potential T→ and magnetic scalar potential Ω . Since the problem is of low frequency and the electric conductivity of biological tissues is very small, consideration of electric vector potential only is quite satisfactory.
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Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields…
Abstract
Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.
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