Legal Cybernetics: An Educational Perspective

Law and control. For the first perception, these concepts may seem different, since the education considers law as a social science and classifies it to the so-called ‘human’ category, while control (from educational point of view) belongs to technical, ‘real’ category. However, in fact, if we deeply examine the essential functions of these concepts, we realise that law is control itself, more precisely, a control in a narrower sense. Therefore, let us try to approach the basic theory of law from a technical, control perspective. The main goals of this approach are on the one hand to change the way like students think, broaden their horizons and perceptions, bringing closer the human and the real sides as well. This way, students would gain an insight into the basics of the other discipline, discover the parallels between these concepts and learn to think more broadly. On the other hand, by using this approach, we can solve the main problems of the current legal regulation. This article deals with how to apply the outlined approach to education, indicating the possible practical application methods and future benefits

Output Feedback Control of Switched Nonlinear Systems: A Gain Scheduling Approach

Switched controller design for nonlinear continuous and discrete-time systems under an arbitrary switching signal using the gain scheduling approach is addressed in this paper. The obtained controller design procedures for continuous and discrete-time systems are in the bilinear matrix inequality form. The proposed design procedure ensures multi parameter-dependent quadratic stability of the switched gain scheduled plant which is associative to a nonlinear plant model and optimal performance defined by quadratic gain scheduled parameters weighting cost function. Example demonstrates the effectiveness of the proposed approaches

A computationally efficient approach for robust gain-scheduled output-feedback LQR design for large-scale systems

This paper proposes a novel and simple control design procedure for sub-optimal robust gain-scheduled (GS) output-feedback linear quadratic regulator (LQR) design for large-scale uncertain linear parameter-varying (LPV) systems. First, we introduce a simple and practical technique to convexify the controller design problem in the scheduled parameters. Then, we propose a computationally efficient iterative Newton-based approach for gain-scheduled output-feedback LQR design. Next, we propose a simple modification to the proposed algorithm to design robust GS controllers. Finally, the proposed algorithm is applied for air management and fueling strategy of diesel engines, where the designed robust GS proportional-integral-derivative (PID) controller is validated on a benchmark model using real-world road profile data

Novel Results on Output-Feedback LQR Design

This paper provides novel developments in output-feedback stabilization for linear time-invariant systems within the linear quadratic regulator (LQR) framework. First, we derive the necessary and sufficient conditions for output-feedback stabilizability in connection with the LQR framework. Then, we propose a novel iterative Newton\u27s method for output-feedback LQR design and a computationally efficient modified approach that requires solving only a Lyapunov equation\ua0at each iteration step. We show that the proposed modified approach guarantees convergence from a stabilizing state-feedback to a stabilizing output-feedback solution and succeeds in solving high dimensional problems where other, state-of-the-art methods, fail. Finally, numerical examples illustrate the effectiveness of the proposed methods

Matlab/Octave toolbox for structurable and robust output-feedback LQR design

In this paper, a structurable robust output-feedback infinite horizon LQR design toolbox for Matlab and Octave is introduced. The aim of the presented toolbox is to fill the gap between available toolboxes for Matlab/Octave by extending the standard infinite horizon LQR design (from Matlab/Control System Toolbox, Octave/Control package) to robust and structurable output-feedback LQR design. The toolbox allows to design a robust infinite horizon output-feedback controller in forms like proportional (P), proportional-integral (PI), realizable proportional-integral-derivative (PID), realizable proportional-derivative (PD), realizable derivative (D), dynamic output-feedback (DOF), dynamic output-feedback with integral part (DOFI), dynamic output-feedback with integral and realizable derivative part (DOFID), and dynamic output-feedback with realizable derivative part (DOFD). In addition, the controller structure for all supported controller types is fully structurable. The toolbox relies on Yalmip (A Matlab/Octave Toolbox for Modeling and Optimization) and on linear matrix inequality solvers like SeDuMi, SDPT3, etc. Notions like "simple", "highly customizable", and "user-friendly" have been used and considered as main terms during the development process

Air-management and fueling strategy for diesel engines from multi-layer control perspective

This paper proposes a novel control design procedure for air management and fueling strategy (AMFS) of diesel engines in lights of a multi-layer control structure (MLCS). Furthermore, novel sufficient stability conditions in the form of linear matrix inequalities are derived (using slack variables to reduce the conservativeness) for grid-based linear parameter-varying systems. The gain-scheduled controller for AMFS is designed to track a reference torquetrajectory requested by higher control layers from MLCS, with the objective of minimizing diesel consumption and pollutants\u27 emissions. For controller design a reduced order grid-based linear parameter-varying model is obtained from the detailed benchmark model published by Eriksson et al. (2016). The controller is validated on the benchmark model using the road profile S\uf6der\ue4lje-Norrk\uf6ping

Robust Guaranteed Cost Output-Feedback Gain-Scheduled Controller Design

In the paper a new robust guaranteed cost output-feedback gain-scheduled PID controller design technique is presented for affine linear parameter-varying systems under polytopic model uncertainty, with the assumption that the scheduled parameters are affected with absolute uncertainty. The proposed centralized or decentralized method is based on the Bellman-Lyapunov equation, guaranteed cost, and parameter-dependent quadratic stability. The robust stability and performance conditions are translated to an optimization problem subject to bilinear matrix inequalities, which can be solved or further linearized. As the main result, the suggested stability and performance conditions without any restrictions on the controller structure are convex functions of the scheduling and uncertainty parameters. Hence, there is no need for applying multi-convexity or other relaxation techniques and consequently the proposed solution delivers a less conservative design method. The viability of the novel design technique is demonstrated and evaluated through numerical examples

Generalized robust gain-scheduled PID controller design for affine LPV systems with polytopic uncertainty

In the paper a generalized guaranteed cost output-feedback robust gain-scheduled PID controller synthesis is presented for affine linear parameter-varying systems under polytopic model uncertainty. The controller synthesis is generalized in a sense that it covers robust, robust gain-scheduled, and robust switched (with arbitrary switching algorithm) PID controller design. The proposed centralized/decentralized controller method is based on Bellman–Lyapunov equation, guaranteed cost, and parameter-dependent quadratic stability. The proposed sufficient robust stability and performance conditions are derived in the form of bilinear matrix inequalities (BMI) which can efficiently be solved or further linearized. As the main result, the suggested performance and stability conditions without any restriction on the controller structure are convex functions of the scheduling and uncertainty parameters. Hence, there is no need for applying multi-convexity or other relaxation techniques and consequently the proposed solution delivers a less conservative design method. The viability of the novel design technique is demonstrated and evaluated through numerical examples

Circum-Arctic distribution of chemical anti-herbivore compounds suggests biome-wide trade-off in defence strategies in Arctic shrubs

Spatial variation in plant chemical defence towards herbivores can help us understand variation in herbivore top-down control of shrubs in the Arctic and possibly also shrub responses to global warming. Less defended, non-resinous shrubs could be more influenced by herbivores than more defended, resinous shrubs. However, sparse field measurements limit our current understanding of how much of the circum-Arctic variation in defence compounds is explained by taxa or defence functional groups (resinous/non-resinous). We measured circum-Arctic chemical defence and leaf digestibility in resinous (Betula glandulosa, B. nana ssp. exilis) and non-resinous (B. nana ssp. nana, B. pumila) shrub birches to see how they vary among and within taxa and functional groups. Using liquid chromatography-mass spectrometry (LC-MS) metabolomic analyses and in vitro leaf digestibility via incubation in cattle rumen fluid, we analysed defence composition and leaf digestibility in 128 samples from 44 tundra locations. We found biogeographical patterns in anti-herbivore defence where mean leaf triterpene concentrations and twig resin gland density were greater in resinous taxa and mean concentrations of condensing tannins were greater in non-resinous taxa. This indicates a biome-wide trade-off between triterpene- or tannin-dominated defences. However, we also found variations in chemical defence composition and resin gland density both within and among functional groups (resinous/non-resinous) and taxa, suggesting these categorisations only partly predict chemical herbivore defence. Complex tannins were the only defence compounds negatively related to in vitro digestibility, identifying this previously neglected tannin group as having a potential key role in birch anti-herbivore defence. We conclude that circum-Arctic variation in birch anti-herbivore defence can be partly derived from biogeographical distributions of birch taxa, although our detailed mapping of plant defence provides more information on this variation and can be used for better predictions of herbivore effects on Arctic vegetation

Circum-Arctic distribution of chemical anti-herbivore compounds suggests biome-wide trade-off in defence strategies in Arctic shrubs

Spatial variation in plant chemical defence towards herbivores can help us understand variation in herbivore top-down control of shrubs in the Arctic and possibly also shrub responses to global warming. Less defended, non-resinous shrubs could be more influenced by herbivores than more defended, resinous shrubs. However, sparse field measurements limit our current understanding of how much of the circum-Arctic variation in defence compounds is explained by taxa or defence functional groups (resinous/non-resinous). We measured circum-Arctic chemical defence and leaf digestibility in resinous (Betula glandulosa, B. nana ssp. exilis) and non-resinous (B. nana ssp. nana, B. pumila) shrub birches to see how they vary among and within taxa and functional groups. Using liquid chromatography-mass spectrometry (LC-MS) metabolomic analyses and in vitro leaf digestibility via incubation in cattle rumen fluid, we analysed defence composition and leaf digestibility in 128 samples from 44 tundra locations. We found biogeographical patterns in anti-herbivore defence where mean leaf triterpene concentrations and twig resin gland density were greater in resinous taxa and mean concentrations of condensing tannins were greater in non-resinous taxa. This indicates a biome-wide trade-off between triterpene- or tannin-dominated defences. However, we also found variations in chemical defence composition and resin gland density both within and among functional groups (resinous/non-resinous) and taxa, suggesting these categorisations only partly predict chemical herbivore defence. Complex tannins were the only defence compounds negatively related to in vitro digestibility, identifying this previously neglected tannin group as having a potential key role in birch anti-herbivore defence. We conclude that circum-Arctic variation in birch anti-herbivore defence can be partly derived from biogeographical distributions of birch taxa, although our detailed mapping of plant defence provides more information on this variation and can be used for better predictions of herbivore effects on Arctic vegetation.Peer reviewe