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Academic literature on the topic 'LPV approach'

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Published: 7 July 2024

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Journal articles on the topic "LPV approach":

1

Fauchet, Floris, Jean-Marc Treluyer, Silvia M. Illamola, Claire Pressiat, Gabrielle Lui, Elodie Valade, Laurent Mandelbrot, et al. "Population Approach To Analyze the Pharmacokinetics of Free and Total Lopinavir in HIV-Infected Pregnant Women and Consequences for Dose Adjustment." Antimicrobial Agents and Chemotherapy 59, no. 9 (July 6, 2015): 5727–35. http://dx.doi.org/10.1128/aac.00863-15.

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ABSTRACTThe aims of this study were to describe the unbound and total lopinavir (LPV) pharmacokinetics in pregnant women in order to evaluate if a dosing adjustment is necessary during pregnancy. Lopinavir placental transfer is described, and several genetic covariates were tested to explain its variability. A total of 400 maternal, 79 cord blood, and 48 amniotic fluid samples were collected from 208 women for LPV concentration determinations and pharmacokinetics analysis. Among the maternal LPV concentrations, 79 samples were also used to measure the unbound LPV concentrations. Population pharmacokinetics models were developed by using NONMEM software. Two models were developed to describe (i) unbound and total LPV pharmacokinetics and (ii) LPV placental transfer. The pharmacokinetics was best described by a one-compartment model with first-order absorption and elimination. A pregnancy effect was found on maternal clearance (39% increase), whereas the treatment group (monotherapy versus triple therapy) or the genetic polymorphisms did not explain the pharmacokinetics or placental transfer of LPV. Efficient unbound LPV concentrations in nonpregnant women were similar to those measured during the third trimester of pregnancy. Our study showed a 39% increase of maternal total LPV clearance during pregnancy, whereas unbound LPV concentrations were similar to those simulated in nonpregnant women. The genetic polymorphisms selected did not influence the LPV pharmacokinetics or placental transfer. Thus, we suggest that the LPV dosage should not be increased during pregnancy.
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Briat, C., O. Sename, and J. F. Lafay. "Design of LPV observers for LPV time-delay systems: an algebraic approach." International Journal of Control 84, no. 9 (September 2011): 1533–42. http://dx.doi.org/10.1080/00207179.2011.611950.

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Liu, Jizhen, Yang Hu, and Zhongwei Lin. "State-FeedbackH∞Control for LPV System Using T-S Fuzzy Linearization Approach." Mathematical Problems in Engineering 2013 (2013): 1–18. http://dx.doi.org/10.1155/2013/169454.

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This paper discusses the linear parameter varying (LPV) gain scheduling control problem based on the Takagi-Sugeno (T-S) fuzzy linearization approach. Firstly, the affine nonlinear parameter varying (ANPV) description of a class of nonlinear dynamic processes is defined; that is, at any scheduling parameter, the corresponding system is affine nonlinear as usual. For such a class of ANPV systems, a kind of developed T-S fuzzy modeling procedure is proposed to deal with the nonlinearity, instead of the traditional Jacobian linearization approach. More concretely, the evaluation system for the approximation ability of the novelly developed T-S fuzzy modeling procedure is established. Consequently, the LPV T-S fuzzy system is obtained which can approximate the ANPV system with required accuracy. Secondly, the notion of piecewise parameter-dependent Lyapunov function is introduced, and then the stabilization problem and the state-feedbackH∞control problem of the LPV T-S fuzzy system are studied. The sufficient conditions are given in linear matrix inequalities (LMIs) form. Finally, a numerical example is provided to demonstrate the availability of the above approaches. The simulation results show the high approximation accuracy of the LPV T-S fuzzy system to the ANPV system and the effectiveness of the LPV T-S fuzzy gain scheduling control.
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Hooshmandi, Kaveh, Farhad Bayat, and Andrzej Bartoszewicz. "Sampled-Data Linear Parameter Variable Approach for Voltage Regulation of DC–DC Buck Converter." Electronics 11, no. 19 (October 6, 2022): 3208. http://dx.doi.org/10.3390/electronics11193208.

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This paper addresses the new method for output voltage regulation of DC–DC buck converter nonlinear systems by a sampled-data linear parameter varying (LPV) controller. For this purpose, an output-error state-space affine LPV model is presented for DC–DC buck converter nonlinear systems. The sampled-data structure of the controller is considered as a time delay in the input, and stabilization conditions are obtained for LPV systems with affine dependence on the parameter by using a parameter-dependent Lyapunov–Krasovskii functional. Then, the design condition of the sampled-data LPV controller with an appropriate sampling period is derived to guarantee that the output voltage of the DC–DC buck converter can be adjusted to the desired voltage. Finally, simulation results are provided to show the validity of the presented approach in practical control applications where there are limitations on the value of the sampling period and the cost of the digital implementation.
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Sala, Antonio. "Stability analysis of LPV systems: Scenario approach." Automatica 104 (June 2019): 233–37. http://dx.doi.org/10.1016/j.automatica.2019.01.032.

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Lu, Qiugang, Hamid Reza Karimi, and Kjell Gunnar Robbersmyr. "A Data-Based Approach for Modeling and Analysis of Vehicle Collision by LPV-ARMAX Models." Journal of Applied Mathematics 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/452391.

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Vehicle crash test is considered to be the most direct and common approach to assess the vehicle crashworthiness. However, it suffers from the drawbacks of high experiment cost and huge time consumption. Therefore, the establishment of a mathematical model of vehicle crash which can simplify the analysis process is significantly attractive. In this paper, we present the application of LPV-ARMAX model to simulate the car-to-pole collision with different initial impact velocities. The parameters of the LPV-ARMAX are assumed to have dependence on the initial impact velocities. Instead of establishing a set of LTI models for vehicle crashes with various impact velocities, the LPV-ARMAX model is comparatively simple and applicable to predict the responses of new collision situations different from the ones used for identification. Finally, the comparison between the predicted response and the real test data is conducted, which shows the high fidelity of the LPV-ARMAX model.
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Tanaudommongkon, Irin, Asama Tanaudommongkon, and Xiaowei Dong. "Development of In Situ Self-Assembly Nanoparticles to Encapsulate Lopinavir and Ritonavir for Long-Acting Subcutaneous Injection." Pharmaceutics 13, no. 6 (June 18, 2021): 904. http://dx.doi.org/10.3390/pharmaceutics13060904.

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Most antiretroviral medications for human immunodeficiency virus treatment and prevention require high levels of patient adherence, such that medications need to be administered daily without missing doses. Here, a long-acting subcutaneous injection of lopinavir (LPV) in combination with ritonavir (RTV) using in situ self-assembly nanoparticles (ISNPs) was developed to potentially overcome adherence barriers. The ISNP approach can improve the pharmacokinetic profiles of the drugs. The ISNPs were characterized in terms of particle size, drug entrapment efficiency, drug loading, in vitro release study, and in vivo pharmacokinetic study. LPV/RTV ISNPs were 167.8 nm in size, with a polydispersity index of less than 0.35. The entrapment efficiency was over 98% for both LPV and RTV, with drug loadings of 25% LPV and 6.3% RTV. A slow release rate of LPV was observed at about 20% on day 5, followed by a sustained release beyond 14 days. RTV released faster than LPV in the first 5 days and slower than LPV thereafter. LPV trough concentration remained above 160 ng/mL and RTV trough concentration was above 50 ng/mL after 6 days with one subcutaneous injection. Overall, the ISNP-based LPV/RTV injection showed sustained release profiles in both in vitro and in vivo studies.
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Sanjuan, Adrián, Damiano Rotondo, Fatiha Nejjari, and Ramon Sarrate. "An Lmi–Based Heuristic Algorithm for Vertex Reduction in LPV Systems." International Journal of Applied Mathematics and Computer Science 29, no. 4 (December 1, 2019): 725–37. http://dx.doi.org/10.2478/amcs-2019-0054.

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Abstract The linear parameter varying (LPV) approach has proved to be suitable for controlling many non-linear systems. However, for those which are highly non-linear and complex, the number of scheduling variables increases rapidly. This fact makes the LPV controller implementation not feasible for many real systems due to memory constraints and computational burden. This paper considers the problem of reducing the total number of LPV controller gains by determining a heuristic methodology that combines two vertices of a polytopic LPV model such that the same gain can be used in both vertices. The proposed algorithm, based on the use of the Gershgorin circles, provides a combinability ranking for the different vertex pairs, which helps in solving the reduction problem in fewer attempts. Simulation examples are provided in order to illustrate the main characteristics of the proposed approach.
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Grzegorzewski, Marek, and Karol Krzysztof Śliwak. "The GNSS System Application in the LPV-200 Landing Approach Procedure. Part I : Approach to Practical Verification." Annual of Navigation 23, no. 1 (December 1, 2016): 251–58. http://dx.doi.org/10.1515/aon-2016-0018.

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Abstract Current RNAV GNSS approach procedures are widely used in Europe and worldwide. The development of the GNSS systems as well as the study and control of satellite signals result in the increasing number of approach types with increasingly higher demands and lower operating minimums. LPV-200 is the precision approach with the most stringent requirements, and operational minimums of up to 200ft. For the purposes of Part I of this paper static measurements were performed in order to compare the signal characteristics with ICAO requirements. On the basis of the measurements′ results, it can be assumed that, within the analyzed period of time, the GNSS signal at the airport in Dęblin only partially met the requirements set for LPV-200 approaches. The data collected were processed and analyzed using Matlab environment.
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Tran, Gia Quoc Bao, Thanh-Phong Pham, Olivier Sename, Eduarda Costa, and Peter Gaspar. "Integrated Comfort-Adaptive Cruise and Semi-Active Suspension Control for an Autonomous Vehicle: An LPV Approach." Electronics 10, no. 7 (March 30, 2021): 813. http://dx.doi.org/10.3390/electronics10070813.

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This paper presents an integrated linear parameter-varying (LPV) control approach of an autonomous vehicle with an objective to guarantee driving comfort, consisting of cruise and semi-active suspension control. First, the vehicle longitudinal and vertical dynamics (equipped with a semi-active suspension system) are presented and written into LPV state-space representations. The reference speed is calculated online from the estimated road type and the desired comfort level (characterized by the frequency weighted vertical acceleration defined in the ISO 2631 norm) using precomputed polynomial functions. Then, concerning cruise control, an LPV H2 controller using a linear matrix inequality (LMI) based polytopic approach combined with the compensation of the estimated disturbance forces is developed to track the comfort-oriented reference speed. To further enhance passengers’ comfort, a decentralized LPV H2 controller for the semi-active suspension system is proposed, minimizing the effect of the road profile variations. The interaction with cruise control is achieved by the vehicle’s actual speed being a scheduling parameter for suspension control. To assess the strategy’s performance, simulations are conducted using a realistic nonlinear vehicle model validated from experimental data. The simulation results demonstrate the proposed approach’s capability to improve driving comfort.
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Journal articles Dissertations / Theses Books

Dissertations / Theses on the topic "LPV approach":

1

Attallah, Aly [Verfasser]. "Distributed Control for Complex Mission Scenarios With Non-Holonomic Agents - An LPV Approach / Aly Attallah." München : Verlag Dr. Hut, 2021. http://d-nb.info/1238423078/34.

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Buľák, Marián. "Trendy modernizace technologií pro řízení letů v okolí civilních letišť." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-401509.

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This master’s thesis deals with technologies intended for flight control during approach and landing. The main focus is on perspective approach systems, including differential technology systems. The thesis is to serve as a study aid for pilots and students of Air Traffic study programme. The main aim of this thesis is to create a qualified whole of perspective and used approach systems. Individual systems include basic characteristics and assessment of their future use. The thesis also includes an analysis of the possibility of implementing the DGNSS system at the airport with multiple runways. Prague-Ruzyně airport was chosen for this purpose. The implementation of this system is compared to other precision approach systems.
3

Attallah, Aly [Verfasser]. "Distributed control for complex mission scenarios with non-holonomic agents – an LPV approach / Aly Saeed Aly Aly Attallah." Hamburg : Universitätsbibliothek der Technischen Universität Hamburg-Harburg, 2021. http://nbn-resolving.de/urn:nbn:de:gbv:830-882.0135993.

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Petersson, Daniel. "A Nonlinear Optimization Approach to H2-Optimal Modeling and Control." Doctoral thesis, Linköpings universitet, Reglerteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-93324.

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Mathematical models of physical systems are pervasive in engineering. These models can be used to analyze properties of the system, to simulate the system, or synthesize controllers. However, many of these models are too complex or too large for standard analysis and synthesis methods to be applicable. Hence, there is a need to reduce the complexity of models. In this thesis, techniques for reducing complexity of large linear time-invariant (lti) state-space models and linear parameter-varying (lpv) models are presented. Additionally, a method for synthesizing controllers is also presented. The methods in this thesis all revolve around a system theoretical measure called the H2-norm, and the minimization of this norm using nonlinear optimization. Since the optimization problems rapidly grow large, significant effort is spent on understanding and exploiting the inherent structures available in the problems to reduce the computational complexity when performing the optimization. The first part of the thesis addresses the classical model-reduction problem of lti state-space models. Various H2 problems are formulated and solved using the proposed structure-exploiting nonlinear optimization technique. The standard problem formulation is extended to incorporate also frequency-weighted problems and norms defined on finite frequency intervals, both for continuous and discrete-time models. Additionally, a regularization-based method to account for uncertainty in data is explored. Several examples reveal that the method is highly competitive with alternative approaches. Techniques for finding lpv models from data, and reducing the complexity of lpv models are presented. The basic ideas introduced in the first part of the thesis are extended to the lpv case, once again covering a range of different setups. lpv models are commonly used for analysis and synthesis of controllers, but the efficiency of these methods depends highly on a particular algebraic structure in the lpv models. A method to account for and derive models suitable for controller synthesis is proposed. Many of the methods are thoroughly tested on a realistic modeling problem arising in the design and flight clearance of an Airbus aircraft model. Finally, output-feedback H2 controller synthesis for lpv models is addressed by generalizing the ideas and methods used for modeling. One of the ideas here is to skip the lpv modeling phase before creating the controller, and instead synthesize the controller directly from the data, which classically would have been used to generate a model to be used in the controller synthesis problem. The method specializes to standard output-feedback H2 controller synthesis in the lti case, and favorable comparisons with alternative state-of-the-art implementations are presented.
5

Yamamoto, Kazusa. "Control of electromechanical systems, application on electric power steering systems." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAT069/document.

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De nos jours, la plupart des véhicules sont équipés de Directions Assistées Electriques (DAE). Ce type de systèmes d'aide à la conduite permet de réduire les efforts que le conducteur doit fournir pour tourner les roues. Ainsi, grâce à un moteur électrique, la DAE applique un couple additionnel en accord avec le comportement du conducteur et la dynamique du véhicule. Il est donc nécessaire de développer une commande en couple basée en particulier sur le signal provenant d'un capteur mesurant le couple agissant au niveau de la barre de torsion (correspondant à une image du couple conducteur). Ce composant est donc essentiel au fonctionnement de la DAE. Or, une défaillance de ce capteur entraine le plus souvent une coupure de l'assistance, pouvant mener à un risque d'accidents. Au regard de la sécurité fonctionnelle, un développement d'un mode de sécurité est recommandé, par de plus en plus de constructeurs automobiles. D'autre part, le marché des équipementiers automobiles reste un secteur très concurrentiel où une baisse des coûts de production est un challenge constamment recherché afin de gagner de nouvelles parts de marchés. Cet aspect de réduction du nombre de capteurs et d'analyse de la dynamique du véhicule s'inscrit donc dans le prolongement de la stratégie de sécurité. Cette thèse, menée au sein de JTEKT Europe, aborde ces divers enjeux. Après une présentation des différents systèmes de directions assistés électriques, des modèles sont présentés pour être utilisés lors de la conception de lois de commande et d'estimateurs. Ensuite deux méthodes d'estimation du couple conducteur sujet aux perturbations de la route et aux bruits de mesures sont proposées : la première est un observateur proportionnel intégral (PI) à synthèse mixte $H_infty/H_2$, et la seconde une approche par filtrage $H_infty$. Puis plusieurs stratégies de commande sont proposées suivant deux cas de figures distincts, soit en utilisant un observateur PI qui estime les états du système et le couple conducteur (LQR, commande LPV par retour d'état), soit en faisant abstraction d'estimateur de couple conducteur (commande $H_infty$ par retour de sortie dynamique). Ce dernier aspect présente l'avantage de nécessiter moins de mesures que le précédent. Ces approches ont été validées en simulation et mises en œuvre sur un véhicule prototype où des résultats prometteurs ont été obtenus
Nowadays, modern vehicles are equipped with more and more driving assistance systems, among them Electric Power Steering (EPS) helps the driver to turn the wheels. Indeed, EPS provides through an electric motor, an additional torque according to the driver's behaviour and the vehicle's dynamics to reduce the amount of effort required to the driver. Therefore, a torque control is developed based on the torque sensor signal which measures in practice the torsion bar torque (corresponding to an image of the driver torque). Consequently, this component is essential to the functioning of EPS systems.Indeed, a torque sensor failure usually leads to shut-off the assistance which may increase the risk of accident. Regarding functional safety, a back-up mode is recommended and required by more and more car manufacturers. On the other hand, a major challenge for automotive suppliers is to reduce cost production in order to meet growing markets demands and manage in the competitive sector. This issue considering a reduction of sensors' numbers and analysis of vehicle's dynamics is therefore an extension of applying the safety strategy. This thesis, carried out within JTEKT Europe, addresses these various issues.After introducing an overview of the different EPS systems, some models used for the design of controllers and estimators are presented. Then, two methods to estimate the driver torque subject to road disturbances and noise measurements are proposed: the first is a proportional integral observer (PI) with mixed synthesis $H_infty / H_2 $, whereas the second is an $ H_infty $ filtering approach. Then, several control strategies are proposed according to two different cases, either by using a PI observer which estimates the system states and the driver torque (LQR, LPV feedback control) or by not taking into account the driver torque estimation ($ H_infty $dynamic output feedback control). This latter approach has the advantage to require less measurements than the previous one. These approaches have been validated in simulation and implemented on a prototype vehicle where promising results have been obtained
6

Bouchama, Fawzia. "Synthèse d’observateurs continus-discrets pour les systèmes non linéaires : Application au Train Autonome." Electronic Thesis or Diss., Valenciennes, Université Polytechnique Hauts-de-France, 2024. http://www.theses.fr/2024UPHF0005.

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Ce travail de thèse contribue au projet collaboratif "Train de Fret Autonome'' porté par la SNCF et a pour but d’automatiser la conduite du train de Fret afin de garantir une conduite autonome fiable et sécurisée dans toutes conditions environnementales. Dans ce contexte, nos contributions concernent le développement d’estimateurs permettant de reconstruire avec précision la position et la vitesse longitudinale du train dans des conditions variables d’adhérence roue-rail. La difficulté majeure provient du fait que les capteurs odométriques embarqués fournissent une mesure de la rotation des roues au niveau des essieux mais ne détectent pas directement le phénomène de glissement des roues, ce qui entraîne une grande imprécision au niveau de l’estimation de la vitesse longitudinale du train. Pour faire face à ce problème, il est nécessaire de faire un recalage précis en utilisant la position du train mesurée par des radio-balises installées sur le rail. Néanmoins, cette mesure est discrète avec une période d’échantillonnage variable. L’un des challenges est de considérer les mesures du train qui combinent à la fois des mesures considérées continues et des mesures apériodiquement échantillonnées. Ainsi, la principale contribution théorique de cette thèse est la conception d’un observateur continu-discret pour une classe de systèmes multi-entrées/multi-sorties avec des sorties continues entachées de bruits de mesures et des sorties apériodiquement échantillonnées. Cet observateur est conçu pour répondre au cahier de charge du projet ``Train de Fret Autonome'' afin d’estimer la vitesse du train dans des conditions variables d’adhérence. Les performances de cet observateur sont montrées en simulation et comparées avec d’autres approches d’estimation de la vitesse du train puis ensuite validées expérimentalement via une campagne d’essais réalisée au Centre d’Essai Ferroviaire de Tronville-en-Barrois
This thesis contributes to the collaborative project "Train de Fret Autonome'' led by the SNCF and aims to control autonomous freight trains in order to guarantee reliable and safe autonomous driving in all environmental conditions. In this context, our contributions concern the development of estimators for accurately reconstructing the train position and longitudinal speed under variable wheel-rail adhesion conditions. The major difficulty arises from the fact that on-board odometric sensors provide a measurement of wheel rotation at axle level, but do not directly detect the phenomenon of wheel slippage, resulting in inaccurate estimation of the longitudinal speed of the train. To overcome this problem, it is necessary to make a precise recalibration using the position of the train measured by radio beacons installed on the rail. Nevertheless, this measurement is discrete with a variable sampling period. One of the challenges is to consider train measurements that combine both continuous and aperiodically sampled measurements. Thus, the main theoretical contribution of this thesis is the design of a continuous-discrete observer for a class of multi-input/multi-output systems with continuous noisy outputs and aperiodically sampled outputs. This observer is designed to meet the specifications of the "Autonomous Freight Train" project, in order to estimate train speed under variable adhesion conditions. The performance of this observer is shown in simulation and compared with other approaches to train speed estimation, then validated experimentally via an experimental test program carried out at the Centre d'Essai Ferroviaire of Tronville-en-Barrois
7

Hvězda, Michal. "Model systému automatického řízení přesného přiblížení a přistání civilního dopravního letadla za použití informací DGNSS." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-438882.

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LPV approaches are being published in the Czech Republic nowadays. Their usage is enabled by the EGNOS European satellite augmentation system. However, published decision heights do not allow equivalence with the ILS CAT I precision approach yet. This work presents the model of automated control of aircraft precision approach. Verification of its functionality shows that applicable airspace requirements can be fulfilled for lower values of decision heights than values already published. The model is developed using contemporary methods of model-based development in the tool supporting common processing of both continuous and discrete signals. Although model architecture follows the structure of commonly used ILS system in definition of coordinate system and in establishing control in two separate directions it allows curved approach. Usage of digital navigation data provided by satellite system opens further opportunities in its usage, expansion and improvements. Model functionality in control of flight course, position and height control is verified in the scenarios covering detailed thesis goals. The goals were defined based on definition of precision approach process and include navigation signal drop-out, impact of wind, various flight path angles and curved approach. Analysis of behavior of controlled aircraft dynamics was a stimulator for research of specific system modules up to the application level, i.e. specific simulations of successful precision approaches.
8

Do, Anh Lam. "Approche LPV pour la commande robuste de la dynamique des véhicules : amélioration conjointe du confort et de la sécurité." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENT114/document.

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Ce travail concerne le développement de méthodes de commandes avancées pour les suspensions automobiles afin d'améliorer la tenue de route des véhicules et le confort des passagers, tout en respectant les contraintes technologiques liées aux actionneurs de suspension (passivité, non-linéarités, limite structurelle). Dans la 1ère partie, nous proposons deux schémas de commande par approche LPV polytopique (Linéaire à Paramètre Variant) et Stabilisation Forte (Strong Stabilization) avec optimisation par algorithme génétique pour résoudre les conflits confort/tenue de route et confort/débattement de suspension. Dans la 2ème partie, pour résoudre le problème complet de commande de suspensions semi-actives, nous développons d'abord une stratégie générique pour les systèmes LPV généraux soumis à la saturation des actionneurs et à des contraintes d'état. Le problème est étudié sous la forme de résolution d'inégalités linéaires matricielles (LMI) qui permettent de synthétiser un contrôleur LPV et un gain anti wind-up garantissant la stabilité et la performance du système en boucle fermée. Ensuite, cette stratégie est appliquée au cas de la commande des suspensions semi-actives. Les méthodes proposées sont validées par une évaluation basée sur un critère industriel et des simulations effectuées sur un modèle non-linéaire de quart de véhicule
This work concerns the development of advanced control methods for automotive suspensions to improve road holding and passenger comfort, while satisfying the technological constraints related to the suspension actuators (passivity, nonlinearity, structural limit). In the first part, we propose two control schemes by polytopic LPV (Linear Parameter Varying) approach and by Strong Stabilization with genetic algorithm optimization to solve the comfort/handling and comfort/suspension travel conflits. In the second part, to solve the full semi-active suspension problem, we develop first a generic strategy for general LPV systems subject to actuator saturation and state constraints. The problem is studied in the form of resolution matrix of linear inequalities (LMI) that allows synthesizing an LPV controller and an anti-windup gain to ensure the stability and performance of the closed-loop system. Second, the theoretical result is applied to the case of semi-active suspension control. The proposed methods are validated by an evaluation based on an industrial standard and simulations on a nonlinear quarter vehicle model
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Petersson, Daniel. "Nonlinear optimization approaches to H2-norm based LPV modelling and control." Licentiate thesis, Linköpings universitet, Reglerteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-59886.

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To be able to analyze certain classes of non-linear systems, it is necessary to try to represent them as linear parameter varying systems or even as linear fractional representations. For linear parameter varying systems and linear fractional representations of systems there exists many advanced analysis methods such as IQC-analysis and μ-analysis. This means that an important intermediate step in all this is to generate a linear parameter varying model that describes these non-linear system sufficiently well. The first contribution in this thesis is a novel method that tries, through nonlinear programming and a quasi-Newton framework, to generate a linear parameter varying model given linearized state space models. The idea behind the method is to preserve the input-output relations of the given linearized systems and, in an H2-measure, find the best one. To handle uncertainties in data an extension of the proposed method is presented. It is shown how the computationally hard robust optimization approach to the uncertain case can be approximated using a problem specific regularization. The second contribution in this thesis is a method for synthesizing output-feedback H2 controllers of arbitrary order. This method also uses non-linear programming and a quasi-Newton framework to achieve this. One great benefit with this method is that it also possible to impose structure in the controller. Both of the methods described above tries to solve non-linear and non-convex problems, which means that the problem of finding a good initial estimate is an important problem. For both methods an initialization procedure is proposed to try to find an initial estimate. The methods are evaluated on several examples and show promising results. A contributing factor is that significant effort has been spent on utilizing the structure of the optimization problems to make the methods efficient.
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Bouali, Anis. "Approche descripteur pour l’analyse et la commande des systèmes LPV rationnels." Nantes, 2008. http://www.theses.fr/2008NANT2119.

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Les caractéristiques dynamiques des processus évoluent parfois largement en fonction des conditions de fonctionnement. Dans ce cas le comportement du système est souvent décrit par un modèle linéaire à paramètres variant (LPV). Cette modélisation recouvre des cas pratiques importants non couverts par les modèles linéaires invariants dans le temps (LTI), sans avoir une généralité telle qu’aucun outil générique ne permette leur analyse ou leur commande. Une sous classe des systèmes LPV se dégage de part sa complexité : celle des systèmes LPV rationnels. Nous démontrons qu’une telle classe de systèmes admet toujours une modélisation équivalente du type LPV descripteur, dite aussi LPV implicite, avec une dépendance paramétrique du type affine. Nous développons un ensemble d’outils d’analyse et de commande pour les systèmes LPV implicites affines. Ces outils sont présentés sous la forme de problèmes d’optimisation sous contraintes LMI (Inégalités Matricielles Linéaires) paramétriques. Leur résolution est grandement facilitée de part la nature affine du modèle implicite considéré. En se basant sur ces résultats et sur une nouvelle notion d’équivalence, nous proposons des outils pour l’analyse, la commande ainsi que la paramétrisation des régulateurs stabilisants des systèmes LPV rationnels. Enfin, quelques exemples numériques permettent d’illustrer ces nouveaux outils et d’en apprécier les intérêts et les limites
Linear parameter dependent models are useful to describe behavior of plants with dynamical characteristics evolving widely with operating conditions. Such models are more general then linear time invariant ones. Among the class of LPV systems those with a rational dependency on the varying parameter are of particular interest. It is shown in this work that such systems can always be recast into equivalent descriptor systems with an affine dependency on the parameters. Original methods for the analysis and the control of LPV descriptor systems have been proposed. In the case of affine descriptor systems, these methods rely on optimization problems having LMI characterizations. Such problems are known to be highly tractable. Based on these results and the properties of the strong equivalence, new conditions for the analysis and the control of rational LPV systems as well as a parameterization of all stabilizing controllers have been presented. Finally, some numerical examples are given in order to appreciate the interest and limitations of the proposed results
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Books on the topic "LPV approach":

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Eckalbar, John. Instrument flying update: What every instrument pilot needs to know about the new rules on approach transitions, WAAS, LPV, LNAV/VNAV, RNAV SIDs, TAWS, and much more. Chico, CA: SkyRoad Projects, 2006.

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White, Lois. Medical-surgical nursing: An integrated approach. 2nd ed. Albany: Delmar Thomson Learning, 2002.

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White, Lois, Gena Duncan, and Wendy Baumle. Medical-surgical nursing: An integrated approach. 3rd ed. Clifton Park, NY: Delmar Cengage Learning, 2013.

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Wright, E. Alaphia. Planning with linear programming: A practical approach with the program LP-TOOLS. Rotterdam: A.A. Balkema, 1996.

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Richards, Marty. Caresharing: A reciprocal approach to caregiving and care receiving in the complexities of aging, illness, or disability. Woodstock, VT: SkyLight Paths Pub., 2008.

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McWilliams, John. How a 'normal science' approach can enhance evidence for a cognitive complexity interpretation of Fiedler's LPC scale. Melbourne: University of Melbourne. Graduate School of Management, 1988.

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V, Gangawane L., and Mayee C. D. 1946-, eds. Biotechnological approaches for the integrated management of crop diseases: Professor L.V. Gangawane festschrift volume. Delhi: Daya Pub. House, 2004.

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Beznosov, Dmitriy, Natal'ya Volkova, svetlana Gurieva, Mariya Zaharova, Tat'yana Kazanceva, Larisa Kotenko, Irina Kuznecova, Larisa Mararica, Lyudmila Pochebut, and Vera Chiker. The social capital of the organization. ru: INFRA-M Academic Publishing LLC., 2024. http://dx.doi.org/10.12737/2082661.

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The monograph is a continuation of the monograph by L.G. Pochebut, A.L. Sventsitsky, L.V. Mararitsa, T.V. Kazantseva, I.V. Kuznetsova "Social capital of personality" (Moscow: INFRA-M, 2014). It contains the theory, methodology and empirical studies of the social capital of organizations. The scientific literature on the problems of social capital of organizations is analyzed. The theory of social capital and research methodology developed by the authors are presented, and empirical research results are presented. The main attention is paid to the socio-psychological approach describing social capital as a system of relationships between employees of an organization. Four aspects of the study of social capital are considered: resource, network, economic and socio-psychological. A methodology for studying social capital has been developed, a socio-psychological methodology "Components of an organization's social capital" and a questionnaire "Personality Networking strategies" have been created. For sociologists, managers, heads of firms and corporations, teachers and researchers, all whose work is related to the management of employee relationships in organizations.
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White, Lois, and Gena Duncan. Medical Surgical Nursing: An Integrated Approach. 2nd ed. Cengage Delmar Learning, 2001.

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Tollefson, James W., and Miguel Pérez-Milans, eds. The Oxford Handbook of Language Policy and Planning. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780190458898.001.0001.

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This Handbook offers a state-of-the-art account of research in language policy and planning (LPP). The Handbook examines the ways in which scholarship in language policy and planning (LPP) has understood the changing relationship between LPP and political-economic conditions, and how this changing relationship has shaped knowledge production in the field. With an underlying interest in language, social critique, and inequality, scholars in this volume work in widely divergent local, regional, national, and institutional settings, to investigate the ongoing processes that have gradually become the focus of contemporary LPP research, in many cases forcing scholars and practitioners in the field to revisit their own assumptions, views, and methodological perspectives. Through a critical examination of LPP, the Handbook offers new directions for a field in theoretical and methodological turmoil as a result of the socioeconomic, institutional, and discursive processes of change taking place under the conditions of late modernity. Chapters in this handbook are divided into three major sections: conceptual underpinnings of LPP; LPP, nation states, and communities; and LPP and late modernity. Subsections include chapters focusing on LPP and nationalism, minorities, standardization, and globalization; LPP in institutions of the nation-state and in communities; language, neoliberalism, and governmentality; language and mobility, diversity, and new social media; and new approaches to extending LPP scholarship. A final chapter offers an integrative summary and suggestions for future directions in LPP research.
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Book chapters on the topic "LPV approach":

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Bribiesca Argomedo, Federico, Emmanuel Witrant, and Christophe Prieur. "A Polytopic LPV Approach for Finite-Dimensional Control." In SpringerBriefs in Electrical and Computer Engineering, 23–32. Cham: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-01958-1_3.

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Corti, Andrea, and Marco Lovera. "Attitude Regulation for Spacecraft with Magnetic Actuators: An LPV Approach." In Control of Linear Parameter Varying Systems with Applications, 339–55. Boston, MA: Springer US, 2012. http://dx.doi.org/10.1007/978-1-4614-1833-7_13.

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Eigner, György, and Levente Kovács. "A TP-LPV-LMI Approach to Control of Tumor Growth." In Recent Advances in Intelligent Engineering, 223–52. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-14350-3_12.

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Coutinho, Daniel F., and Alain Vande Wouwer. "A Robust H∞ Quasi-LPV Approach for Designing Nonlinear Observers." In Recent Advances in Optimization and its Applications in Engineering, 21–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-12598-0_2.

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Farhood, Mazen. "A Parameter-Dependent Lyapunov Approach for the Control of Nonstationary LPV Systems." In Control of Linear Parameter Varying Systems with Applications, 105–26. Boston, MA: Springer US, 2012. http://dx.doi.org/10.1007/978-1-4614-1833-7_5.

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Zhang, Hui, Rongrong Wang, and Junmin Wang. "Sideslip Angle Estimation of An Electric Ground Vehicle Via Finite-Frequency $$\mathcal {H}_{\infty }$$ Approach." In Robust Gain-Scheduled Estimation and Control of Electrified Vehicles via LPV Technique, 75–95. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-8509-6_3.

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Palmeira, Alessandra Helena Kimura, Joao Manoel Gomes da Silva, and Jeferson Vieira Flores. "Regional Stability of Nonlinear Sampled-Data Controlled Systems Under Actuator Saturation: A Quasi-LPV Approach." In Advances in Delays and Dynamics, 189–207. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-89014-8_10.

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Bougatef, Zina, Nouceyba Abdelkrim, Abdel Aitouche, and Mohamed Naceur Abdelkrim. "Sensor Fault Detection and Estimation Based on UIO for LPV Time Delay Systems Using Descriptor Approach." In Studies in Systems, Decision and Control, 55–69. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-1746-4_3.

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Lovera, Marco, Marco Bergamasco, and Francesco Casella. "LPV Modelling and Identification: An Overview." In Robust Control and Linear Parameter Varying Approaches, 3–24. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-36110-4_1.

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Henrion, Didier. "Positive Polynomial Matrices for LPV Controller Synthesis." In Robust Control and Linear Parameter Varying Approaches, 87–96. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-36110-4_4.

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Conference papers on the topic "LPV approach":

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Toth, Roland, Jan C. Willems, Peter S. C. Heuberger, and Paul M. J. Van den Hof. "A behavioral approach to LPV systems." In 2009 European Control Conference (ECC). IEEE, 2009. http://dx.doi.org/10.23919/ecc.2009.7074700.

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Wollnack, Simon, and Herbert Werner. "LPV-IO controller design: An LMI approach." In 2016 American Control Conference (ACC). IEEE, 2016. http://dx.doi.org/10.1109/acc.2016.7526080.

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Lejun Chen, R. J. Patton, and S. Klinkhieo. "Robust LPV Estimator Approach to Friction Diagnosis." In UKACC International Conference on CONTROL 2010. Institution of Engineering and Technology, 2010. http://dx.doi.org/10.1049/ic.2010.0279.

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Farhood, Mazen, and Eric Feron. "An LPV Approach to Obstacle-Sensitive Trajectory Regulation." In ASME 2009 Dynamic Systems and Control Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/dscc2009-2772.

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The paper focuses on the control of vehicular systems along trajectories in the presence of obstacles. We design parameter-dependent controllers which guarantee closed-loop stability and performance of the vehicle’s regulation loop. In addition, the control strategy changes depending on the position of the vehicle in the obstacle environment so that the critical outputs are given the most attention. We also provide a fast and easy-to-implement algorithm for online controller construction. Last, the proposed approach is applied to a three-degree-of-freedom helicopter.
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Soliman, M., H. Emara, A. Elshafei, A. Bahgat, and O. P. Malik. "Exponential stabilization of LPV systems: An LMI approach." In 2008 Canadian Conference on Electrical and Computer Engineering - CCECE. IEEE, 2008. http://dx.doi.org/10.1109/ccece.2008.4564524.

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Taamallah, Skander, Xavier Bombois, and Paul M. J. Van den Hof. "Affine LPV modeling: An H∞ based approach." In 2013 IEEE 52nd Annual Conference on Decision and Control (CDC). IEEE, 2013. http://dx.doi.org/10.1109/cdc.2013.6760295.

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Balas, G., J. Bokor, and Z. Szabo. "Failure detection for LPV systems - a geometric approach." In Proceedings of 2002 American Control Conference. IEEE, 2002. http://dx.doi.org/10.1109/acc.2002.1025342.

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Prempain, Emmanuel, and Ian Postlethwaite. "A feedforward control synthesis approach for LPV systems." In 2008 American Control Conference (ACC '08). IEEE, 2008. http://dx.doi.org/10.1109/acc.2008.4587050.

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Cai, Xuejing, and Fen Wu. "A Multiobjective Solution Approach to Fault Detection and Isolation of LPV Systems." In ASME 2008 Dynamic Systems and Control Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/dscc2008-2154.

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In this paper, we consider the fault Detection and isolation (FDI) problem for faulty linear parameter-varying (LPV) systems subject to disturbances and propose a observer-based solution by using multiobjective optimization techniques. To simply the design process, a general faulty LPV system will be constructed from standard LPV description by converting actuator/system component faults into sensor faults at first. Then a bank of LPV FDI filters will be designed to identify each fault. Each FDI filter could generate a residual signal to track individual fault with minimum error and suppressing the effects of disturbances and other fault signals. The design of FDI filters will be formulated as multiobjective optimization problems in terms of linear matrix inequalities (LMIs) and can be solved efficiently. Two numerical examples are also presented to demonstrate the proposed fault detection and isolation approach on both LPV and LTI systems.
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van Wingerden, Jan-Willem, and Michel Verhaegen. "Subspace IDentification of MIMO LPV systems: The PBSID approach." In 2008 47th IEEE Conference on Decision and Control. IEEE, 2008. http://dx.doi.org/10.1109/cdc.2008.4738626.

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Reports on the topic "LPV approach":

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Yu, Mei, Pengyu Wang, Binbin Li, Qiaoling Ruan, Jingzi ZhangBao, Lei Wu, Xiaoshuang Zhang, Zhaolin Liu, and Fang Huang. NRSF Negatively Regulates Microglial Pro-Inflammatory Activation. Progress in Neurobiology, May 2024. http://dx.doi.org/10.60124/j.pneuro.2024.20.02.

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Microglial activation contributes to neurological disorders like Parkinson’s disease (PD), and modulating this activation is a potential therapeutic approach. The neuron-restrictive silencer factor (NRSF) functions as a negative regulator of gene transcription through epigenetic modifications. While previous research has primarily examined the role of NRSF in neuronal differentiation and injury, emerging evidence indicates that NRSF also plays a significant role in maintaining the phenotype of glial cells. In this study, we explored the role and underlying mechanisms of NRSF in lipopolysaccharide (LPS)-induced pro-inflammatory or interleukin-4 (IL4)-induced anti-inflammatory phenotype of microglial activation. Following LPS stimulation, the nuclear localization of NRSF increased in BV2 microglial cells, primary mouse microglia, and microglia within the substantia nigra of PD mice. Knockdown of NRSF enhanced the expression of inflammation-related factors induced by LPS via the mitogen-activated protein kinase-extracellular signal-regulated kinase (MAPK-ERK) and nuclear factor-κB (NF-κB) p65 signalling pathways in BV2 cells. Moreover, the culture medium from LPS-treated NRSF knockdown BV2 cells exerted greater toxic effects on human neuroblastoma SH-SY5Y cells compared to the control. However, NRSF knockdown exerted inconsistent effects on the expression of anti-inflammatory-related genes in IL4-treated BV2 cells. Our findings suggest that NRSF knockdown promotes microglial pro-inflammatory activation.
2

Chauhan, Vinod. DTPH56-05-T-003A The Remaining Strength of Corroded Low Toughness Pipe. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), February 2009. http://dx.doi.org/10.55274/r0010967.

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Methods including ASME B31G, Modified ASME B31G and RSTRENG and LPC have been developed, validated and matured to the extent that they are now incorporated in standards and regulatory requirements. However, these methods are based on the assumption that the pipe fails via a ductile mechanism, i.e., the line pipe material has sufficient toughness to prevent a toughness dependent failure. This limits the application of the existing methods to materials that have sufficient toughness.�A modeling study has been undertaken in the present project using the local approach to brittle fracture to predict failure probabilities for a range of corrosion defect geometries.
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Shalganov, Tchavdar, Milko Stoyanov, and Vassil Traykov. Outcomes following catheter ablation for ventricular tachycardia in adult patients with structural heart disease and implantable cardioverter-defibrillator: protocol for an updated systematic review and meta-analysis of randomized studies. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, June 2022. http://dx.doi.org/10.37766/inplasy2022.6.0080.

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Review question / Objective: Does catheter ablation for scar-related monomorphic ventricular tachycardia improve outcomes (defined as any appropriate ICD therapy, appropriate ICD shocks, all-cause mortality, VT storm, cardiovascular mortality, cardiovascular hospitalizations, complications) in adult patients with ischemic or non-ischemic cardiomyopathy and implantable cardioverter-defibrillator? Condition being studied: Ventricular tachycardia in patients with structural heart disease is usually an arrhythmia using the myocardial scar as a substrate for reentry. It poses a risk of syncope and sudden cardiac death, especially in patients with reduced ejection fraction. Most antiarrhythmic drugs are of little value and their use is restricted in patients with LV systolic dysfunction. Catheter ablation is a viable option for the treatment of ventricular tachycardia. In patients with previous myocardial infarction the arrhythmogenic scar is located most frequently subendocardially and is readily accessible using endocardial approach, while in non-ischemic cardiomyopathy the scar is frequently located in the midmyocardial or subepicardial layers. This is the reason endocardial catheter ablation to be less effective in those patients and to more often necessitate epicardial approach.
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Amirav, Aviv, and Steven Lehotay. Fast Analysis of Pesticide Residues in Agricultural Products. United States Department of Agriculture, November 2002. http://dx.doi.org/10.32747/2002.7695851.bard.

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The overall theme of this project was to increase the speed of analysis for monitoring pesticide residues in food. Traditionally, analytical methods for multiple pesticides are time-consuming, expensive, laborious, wasteful, and ineffective to meet critical needs related to food safety. Faster and better methods were needed to provide more cost-effective detection of chemical contaminants, and thus provide a variety of benefits to agriculture. This overarching goal to speed and improve pesticide analysis was successfully accomplished even beyond what was originally proposed by the investigators in 1998. At that time, the main objectives of this project were: 1) to further develop a direct sample introduction (DSI) device that enables fast sampling and introduction of blended-only agricultural products for analysis by gas chromatography (GC); 2) to evaluate, establish, and further develop the method of simultaneous pulsed flame photometric detector (PFPD) and mass spectrometry (MS) detection for enhanced pesticide identification capabilities; and 3) to develop a new and novel MS pesticide analysis method, based on the use of supersonic molecular beams (SMB) for sampling and ionization. The first and third objectives were successfully accomplished as proposed, and the feasibility of the second objective was already demonstrated. The capabilities of the GC/SMB-MS approach alone were so useful for pesticide analysis that the simultaneous use of a PFPD was considered superfluous. Instead, the PFPD was investigated in combination with an electron-capture detector for low-cost, simultaneous analysis of organophosphorus and organochlorine pesticides in fatty foods. Three important, novel research projects not originally described in the proposal were also accomplished: 1) development of the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for pesticides in foods; 2) development and optimization of a method using low-pressure (LP) GC/MS to speed pesticide residue analysis; and 3) innovative application of analyte protectants to improve the GC analysis of important problematic pesticides. All of the accomplishments from this project are expected to have strong impact to the analytical community and implications to agriculture and food safety. For one, an automated DSI approach has become commercially available in combination with GC/MS for the analysis of pesticide residues. Meanwhile, the PFPD has become the selective detector of choice for the analysis of organophosphorus pesticides. Great strides were made in SMB-MS through the manufacture of a prototype "Supersonic GC/MS" instrument, which displayed many advantages over commercial GC/MS instruments. Most notably, the QuEChERS method is already being disseminated to routine monitoring labs and has shown great promise to improve pesticide analytical capabilities and increase lab productivity. The implications of these developments to agriculture will be to increase the percentage of food monitored and the scope of residues detected in the food, which will serve to improve food safety. Developed and developing countries alike will be able to use these methods to lower costs and improve results, thus imported/exported food products will have better quality without affecting price or availability. This will help increase trade between nations and mitigate certain disputes over residue levels in imported foods. The improved enforcement of permissible residue levels provided by these methods will have the effect to promote good agricultural practices among previously obstinate farmers who felt no repercussions from illegal or harmful practices. Furthermore, the methods developed can be used in the field to analyze samples quickly and effectively, or to screen for high levels of dangerous chemicals that may intentionally or accidentally appear in the food supply.

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