Bibliografías temáticas / Command H∞

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Literatura académica sobre el tema "Command H∞"

Autor: Grafiati
Publicado: 25 de mayo de 2024

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Artículos de revistas sobre el tema "Command H∞"

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Zheng, Hong, Yue Lei Shi, and Hang Hui Zhang. "Continuous PWM Modulation Strategy for NPC/H and H Bridge Hybrid Multilevel Converter." Advanced Materials Research 748 (August 2013): 510–13. http://dx.doi.org/10.4028/www.scientific.net/amr.748.510.

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f the ratio of NPC/H and H bridge hybrid multilevel converters DC supply voltage changed, the output voltage PWM waveform will be discontinuous. Thus an improved topology and control strategy is proposed. In new method, master converter operates at the fundamental frequency based on command voltage, slave converter adopts carrier phase shifted PWM technology (CPS-SPWM) at a higher frequency to enhance the quality of output voltage waveform. The amplitude of command voltage is higher than output voltage amplitude of the master converter at any time, to ensure that output voltage variation of both converters keeps in the same direction without any current flow backwards. Matlab simulation results demonstrate the effectiveness of the proposed control strategy and topology.
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Huang, Si Jun. "MPEG digital storage media (DSM) control command." Signal Processing: Image Communication 6, no. 6 (1995): 521–24. http://dx.doi.org/10.1016/0923-5965(94)00035-h.

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Silva, Carolina Gomes da, Luma da Silva Miranda, Manuella Carnaval, and Claudia de Souza Cunha. "command intonation in Brazilian Portuguese: a dialectal description from ALiB corpus." Journal of Speech Sciences 5, no. 2 (2021): 29–45. http://dx.doi.org/10.20396/joss.v5i2.15063.

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In this paper, we described the command intonational contours in the twenty-five Brazilian capitals included in the corpus “Linguistic Atlas of Brazil” (ALiB). This work aims at: (i) describing the intonational contour of twenty-five capitals from the corpus ALiB; (ii) comparing the intonation of the directive speech acts in the five Brazilian regions and (iii) proposing a phonological representation of the variation of this contour. Our corpus is composed of fifty imperative utterances produced by male and female speakers of the analyzed capitals. We observed that there is a predominance of a rising F0 movement in the prenucleus of the command contours with the phonological notation L*+H or L+H* in the twentyfive Brazilian capitals. In the nuclear position, the pitch accent can be defined for the majority of the capitals as H+L*L%, a falling F0 movement, with the variant H*L% for the capital Belém (PA). The capital that presented a different F0 movement in the nucleus was Florianópolis (SC) that showed the predominance of a rising-falling F0 movement represented as L+H*L%.
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4

Gadewadikar, J., Frank Lewis, Kamesh Subbarao, and Ben M. Chen. "Structured H-Infinity Command and Control-Loop Design for Unmanned Helicopters." Journal of Guidance, Control, and Dynamics 31, no. 4 (2008): 1093–102. http://dx.doi.org/10.2514/1.31377.

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HELTON, J. WILLIAM, MICHAEL L. WALKER, and WEI ZHAN. "H∞ control of systems with compensators which read the command signal." International Journal of Control 64, no. 1 (1996): 9–27. http://dx.doi.org/10.1080/00207179608921614.

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6

Stumpff Morrison, Andrew. "Law Is the Command of the Sovereign: H. L. A. Hart Reconsidered." Ratio Juris 29, no. 3 (2016): 364–84. http://dx.doi.org/10.1111/raju.12133.

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Glester, Andrew. "Commanding missions, making history." Physics World 35, no. 6 (2022): 49–50. http://dx.doi.org/10.1088/2058-7058/35/06/30.

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Behrens, Roy R. "Abbott H. Thayer's Anticipation of a Computer-Based Method of Working." Leonardo 34, no. 1 (2001): 19–20. http://dx.doi.org/10.1162/002409401300052433.

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This article describes the practice of Abbott H. Thayer (1849-1921) of working on several copies of the same painting, taking each to a different conclusion. It compares that method to the cur-rent computer-based practice of using the SAVE AS command to create copies of a digital artwork or design, which can then also be taken to different conclusions.
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CHEN, Mou. "Design of H∞ Flight Controller for Fighter under Tactical Data-link Command." Acta Automatica Sinica 34, no. 2 (2009): 211–14. http://dx.doi.org/10.3724/sp.j.1004.2008.00211.

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Guinea-Martin, Daniel, and Ricardo Mora. "Computing decomposable multigroup indices of segregation." Stata Journal: Promoting communications on statistics and Stata 22, no. 3 (2022): 521–56. http://dx.doi.org/10.1177/1536867x221124471.

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Eight multigroup segregation indices are decomposable into a between and a within term. They are two versions of 1) the mutual information index, 2) the symmetric Atkinson index, 3) the relative diversity index, and 4) Theil’s H index. In this article, we present the command dseg, which obtains all of them. It contributes to the stock of segregation commands in Stata by 1) implementing the decomposition in a single call, 2) providing the weights and local indices used in the computation of the within term, 3) facilitating the deployment of the decomposability properties of the eight indices in complex scenarios that demand tailor-made solutions, and 4) leveraging sample data with bootstrapping and approximate randomization tests. We analyze 2017 census data of public schools in the United States to illustrate the use of dseg. The subject topic is school racial segregation.
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Tesis sobre el tema "Command H∞"

1

Cox, Douglas A. "Airpower leadership on the front line General George H. Brett and combat command /." Maxwell Air Force Base, Ala. : Air University, 2004. https://research.maxwell.af.mil/papers/ay2004/ari/Cox.pdf.

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Zhou, Huide. "Concepts thermodynamiques et d'entropie pour la modélisation et la régulation d'un réseau de transport." Thesis, Belfort-Montbéliard, 2014. http://www.theses.fr/2014BELF0231/document.

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Dans ce travail, nous avons présenté notre contribution portant sur la modélisation et le contrôle a priori de congestion des réseaux de carrefours signalisés. De point de vue de la modélisation, nous avons introduit un nouveau regard sur les systèmes de transport en proposant un premier travail sur la manière dont les liens se tissent entre ces systèmes et la thermodynamique. Le point de vue dominant est l'assimilation des véhicules à l'énergie fournie ou/et échangée entre les intersections signalisées. L'avantages majeur de la modélisation thermodynamique est l'introduction de la notion d'entropie du transport mesurant le désordre du système. Elle peut être considérée non seulement comme un moyen pour la compréhension des phénomènes du trafic, mais aussi comme un outil d'évaluation surtout lorsqu'il s'agit de traiter des réseaux de grande taille. De point de vue du contrôle, nous nous sommes intéressés essentiellement à un travail en amont permettant d'éviter la congestion en forçant les files d'attente à ne pas dépasser le niveau du trafic correspondant à l'optimum opérationnel des lignes. Nous avons traité le problème de deux façons différentes. La première fait appel à l’approche de la commande dissipative. Nous avons exploité cet outil pour arriver à des résultats théoriques dont la vérification permet de conclure sur la possibilité de dissiper les véhicules au moyen d'une action de la commande adéquate. L'existence d'une commande dissipative est caractérisée par la faisabilité de certaines inégalités matricielles linéaires (LMI). La deuxième façon de traiter notre problème de commande fait appel à la commande H∞. Nous avons tiré profit de cet outil pour développer des résultats assurant l'invariance positive en boucle fermée d'un domaine ellipsoïdal contenu dans l'ensemble des contraintes. Le test d'existence et le calcul d'une loi de commande robuste par retour d'état peut alors se faire de façon simple par la résolution d'un problème de programmation linéaire convexe. Enfin, ses travaux ont été appliqués sur deux types de réseaux de carrefours, artériel et en grille afin de montrer l'intérêt des résultats<br>In this work, we have presented a thermodynamic point of view for the transportation network. Analogies have been drawn between thermodynamic and transportation systems by considering traffic lanes as thermodynamic sub-systems and the vehicles as the abstract energy supplied to them. In addition, the concepts of thermal capacity and temperature are also introduced into transportation context to correspond to lane capacity and occupancy respectively. Then, it has been demonstrated that the first law of thermodynamics corresponds to the conservation of vehicles. It is also demonstrated that the transportation network can have a similar notion of entropy. Such transportation entropy is a measure of disorder of the system and hence may provide deep insight in the analysis of transportation control problems. In particular, this work has presented a dissipativity phenomenon of transportation entropy that reduces the system disorder and hence renders the system better organized. Though this phenomenon doesn’t exist naturally in transportation context, the ways to construct feedback control strategies have been proposed to achieve such objective by means of Linear Matrix Inequalities (LMIs). However, since transportation systems involve massive complex human activities, there exist substantial unpredictable uncertainties of the traffic demands. In this context, we have proposed a robust controller for disturbance attenuation of transportation network. The errors between input flows and the nominal ones are considered as disturbances and a constrained H∞ control has been formulated in terms of maximization of the tolerance under control constraints. The problem of disturbance attenuation is solved by means of a convex optimization with Linear Matrix Inequality. Finally, two types of networks (arterial and grid) are carried out to illustrate the performances of our strategies
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Gauthier, Christophe. "Commande multivariable de la pression d'injection dans un moteur diesel Common Rail." Grenoble INPG, 2007. http://www.theses.fr/2007INPG0054.

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Les normes sur les émissions de polluants des automobiles sont de plus en plus sévères. Les moteurs à injection directe à rampe commune permettent d'atteindre ces exigences notamment grâce à l'injection du carburant à très haute pression. Cette pression varie de 200 à 1600 bar selon le point de fonctionnement du véhicule. L'objectif des travaux de thèse est de réaliser le contrôle de la pression du carburant avec deux contraintes principales : proposer une méthodologie de calibration du contrôleur à partir des caractéristiques techniques du système d'injection et améliorer à la fois la performance et la robustesse du contrôle. Les travaux réalisés se décomposent comme suit : étude du système d'injection et développement d'un modèle de connaissance ; développement des stratégies et des lois de commande ; mise en application sur véhicule. Les essais réalisés sur véhicule ont montré une amélioration des performances et de la robustesse du contrôle de la pression du carburant obtenue par la proposition d'une nouvelle méthodologie de calibration. Celle-ci est basée par l'obtention du contrôleur à partir des caractéristiques techniques du système d'injection et par l'utilisation de lois de commande avancées (commande H8 pour les systèmes Linéaires à Paramètres Variants (LPV)). En particulier l'approche basée sur l'utilisation des Transformations Linéaires Fractionnelles (LFT) a été considérée<br>Vehicle exhaust emissions are today more and more restrictive. Common Rail engines allow to reach these requirements thanks to the high pressure injection. This pressure can vary from 200 up to 1600 bar according to the engine torque and speed. The goal of this work is to define the rail pressure controller based on the Common Rail features and to improve performance and robustness. Works have been done as follows: study of the Common Rail system and development of the physical model ; development of strategies and command laws ; real tests on vehicle. Vehicle tests showed a high improvement on performance and robustness thanks to the new methodology based on the Common Rail features and the advanced command laws (H8 control for Linear Parameter Varying systems). In particular the Linear Fractional Transformation (LFT) approach has been considered
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Gallet, Alain. "Isolation vibratoire par commande robuste H "infini"." Aix-Marseille 1, 1996. http://www.theses.fr/1996AIX11022.

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L'objectif de ce travail est de resoudre un probleme de controle en vue de l'isolation vibratoire d'un systeme mecanique constitue par l'assemblage d'une structure continue elastique a isoler et d'une source d'excitation vibratoire polluante. Les deux structures sont reliees par des plots de suspension actifs dont les commandes sont les inconnues de notre probleme de controle. Une modelisation discrete de la structure couplee est obtenue a partir de l'analyse modale du systeme conservatif passif. L'utilisation des fonctions de green de la structure continue, permet de caracteriser de maniere exacte les modes propres du systeme couple. Un algorithme original est propose pour resoudre ce probleme. Pour satisfaire a des objectifs de stabilite et de performance robustes, le probleme de controle vibratoire par retroaction est defini, a partir de la representation discrete du systeme couple, par la minimisation d'un critere portant sur la norme infinie (controle h-infini) de la matrice de transfert. Nous developpons une formulation du probleme de controle adaptee a la representation modale du systeme pour realiser une discrimination frequentielle des performances a moindre cout en terme de taille du controleur. Nous formulons les objectifs de robustesse a des incertitudes de parametres et a des erreurs de troncature modale en utilisant la notion de valeur singuliere structuree. Ces demarches sont illustrees numeriquement. Nous proposons une approche sous-optimale originale pour le calcul de lois de commandes locales decouplees, basee sur des considerations de robustesse. Enfin, une simulation numerique a partir de donnees experimentales mesurees sur un banc d'essai existant au laboratoire est presentee
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Xu, Cheng-Zhong. "Quelques résultats concrets sur la commande linéaire par l'approche H[infini]." Grenoble INPG, 1989. http://www.theses.fr/1989INPG0042.

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Présentation de résultats théoriques d'existence et d’unicité des solutions des équations aux dérivées partielles décrivant le procédé ainsi que des résultats de stabilité. Factorisation externe-interne des fonctions de transfert transcendantes et calcul de la commande optimale ∞
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6

Cassany, Louis. "Modélisation et régulation de la glycémie dans la maladie du diabète." Thesis, Bordeaux, 2022. http://www.theses.fr/2022BORD0224.

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Aujourd'hui, les technologies de mesure CGM (Continuous Glucose Monitoring) et d’insulinothérapie par pompe à insuline révolutionnent le traitement du diabète. Les capteurs sont toutefois limités à la mesure de glucose et les algorithmes d’insulinothérapie sont ainsi limités. L’action menée par le consortium de recherche constitué de l'IMS (Laboratoire de l'Intégration du Matériau au Système), du CBMN (laboratoire de Chimie et Biologie des Membranes et Nano-objets) et du CHU (Centre Hospitalier Universitaire) de Bordeaux, rassemble des diabétologues et des spécialistes de la biologie des îlots pancréatiques, de la micro-électronique et de l’automatique, pour développer un nouveau dispositif de mesure et de contrôle de glycémie qui inclut la prise en compte de différentes hormones dans la mesure. Les travaux de cette thèse s’inscrivent dans ce contexte. Le travail de thèse consiste à utiliser les outils de la commande robuste pour établir de nouveaux algorithmes d’insulinothérapie (contrôle de pompe à insuline) permettant de s’adapter aux grandes variabilités des patients (âge, poids...) et des conditions de vie (sport, sommeil, repas de famille, etc.). La démonstration « in silico » des solutions développées est effectuée à l’aide du simulateur UVA/PADOVA, simulateur Matlab/Simulink certifié par la FDA (Food and Drug Administration) pour les essais pré-cliniques<br>Recent advancements in CGM sensors (Continuous Glucose Monitoring) and insulin pumps considerably improved the treatment of diabetes. However, CGM sensors can only measure the blood glucose level, limiting the insulin therapy algorithms. The IMS laboratory (Integration: from Material to Systems), the CBMN laboratory (Chemistry, Biology of Membranes and Nano-objects) and the CHU (University Hospital Center) gather specialists in diabetes, pancreatic islet biology, microelectronics and automatic control in order to develop new solutions for glycemic measurement and regulation for patients with diabetes. The work of this thesis falls within this context. The goal is to use the tools of the robust control theory in order to develop new insulinotherapy algorithms that can adapt to the physiological variability of the patient (age, weight...). These algorithms will be evaluated in the UVA/Padova simulator, currently the only simulator approved by the FDA (Food and Drug Administration) for in silico pre-clinical tests
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Samblancat, Christiane. "Commande robuste multivariable : applications à l'hélicoptère." Toulouse, ENSAE, 1991. http://www.theses.fr/1991ESAE0014.

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Le travail présenté dans cette thèse est une étude à la fois théorique et pratique de la h-infini synthèse. La partie théorique met l'accent sur la formulation du problème d'optimisation h-infini, les algorithmes de calcul et les conditions de résolution. La partie présente une étude complète et réaliste de la synthèse de lois de commande pour un hélicoptère. En particulier, une première application directe de la méthode h-infini permet de mettre en évidence ses avantages (niveau de performance, traitement explicite de la robustesse vis-à-vis des dynamiques négligées et du compromis performance/robustesse) mais aussi ses faiblesses (complexité des compensateurs, caractéristiques modales médiocres, niveau de robustesse aux variations paramétriques faible). Il s'ensuit qu'une application directe et systématique de la synthèse h-infini ne fournit pas une solution réellement satisfaisante au problème posé. Afin de s'affranchir des difficultés mises en évidence lors de la synthèse directe, une méthodologie de commande mixte est finalement proposée. La structure de commande associée est composée d'une boucle interne qui réalise essentiellement une préstabilisation et un prédécouplage du système en termes de structures propres. Une boucle externe de nature h-infini vient compléter la boucle interne, gére le suivi des consignes et assure la robustesse vis-à-vis de la dynamique négligée. On montre de plus, qu'en regard des lois purement h-infini cette méthodologie de synthèse mixte permet de réduire la complexité de la loi de commande et apporte également une solution satisfaisante aux problèmes de caractère modal et paramétrique soulevés précédemment.
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Murciano, Alex. "Algorithmes de la commande robuste et implémentation logicielle." Paris 9, 1991. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=1991PA090006.

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On présente les différents algorithmes de la commande robuste et plus particulièrement ceux conduisant à la synthèse de la commande h-infini. Les problèmes de commande robuste sont mis sous la forme d'un problème dit standard qui consiste à augmenter le système nominal en prenant en considération les spécifications de robustesse exigées, puis à minimiser un critère de nature fréquentielle de type quadratique ou infini. Il existe deux approches différentes pour concevoir le contrôleur h-infini. L'approche de Nehari consiste à trouver la projection d'un système anti-stable sur l'espace des systèmes stables muni de la norme h-infini. L'approche de Glover dite également ultra-moderne consiste à résoudre deux équations de Riccati puis à mettre sous une forme descripteur le contrôleur. L'algorithme qui est présenté et implémenté dans la thèse constitue une amélioration de la méthode de Glover conduisant à des calculs plus robustes. Les algorithmes de la commande robuste ont été implémentés dans Basile logiciel de C. A. O en automatique. Une bibliothèque de macros Basile a été réalisée permettant de résoudre des problèmes standards h-infini et plus généralement, d'étudier la robustesse des systèmes linéaires. De manière à valider les algorithmes et de donner des exemples de problèmes h-infini, des applications académiques et industrielles (avion, satellite) sont traitées en détails
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Falcón, Prado Ricardo. "Active vibration control of flexible structures under input saturation through delay-based controllers and anti-windup compensators." Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASG042.

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Dans ce travail, on traite le problème du commande actif des vibrations robustes pour une structure mécanique flexible à travers des techniques pour des systèmes à dimensions infinis et finis. Les approches abordées sont réglées pour une commande à retour de sortie basée sur une commande aux actions retardées proportionelles, par une approche basée sur quasipolynomials,et une commande synthétisée par la méthode H∞avec une approche par LMIs. Le but c’est l’analyse de ses capabilités pour amortisser les modes vibratoires dans une bande passante d’intérêt, et éviter les effets dénommés de phénomène “spillover”. Cettes commandes sont sythétisés à travers d’un modèle de dimensions finies,dérivé à partir d’un analyse des dimensions finies des structures mécaniques, combiné avec des methodes de réduction.Les structures flexibles envisagées ici sont, d’abord,une poutre flexible d’aluminium à la configuration Euler-Bernoulli, dont un bout est encastrée et l’autre libre, deuxièmement,une membrane axisymmetrique. Chaque système est instrumenté d’un capteur et d’un actionneur piézoélectrique,ils sont bien soumises à chaque coté des structures et elles sont bien placées. Notre intention est d’examiner les performances susmentionnés par les environnements de simulation numérique et la mise en oeuvre à titre expérimental<br>In this work, the problem of active vibration control of flexible mechanical structures is addressed through infinite and finite dimensional techniques. The compared approaches are adjusted for an output feedback controller based on delayed proportional actions,through a quasipolynomial-based approach, and an optimalH∞ controller design computed with an LMI approach.They are shown in order to analyze their capabilities to damp some vibrational modes in the frequency band with of interest, and to avoid the so called “spillover”phenomenon. These controllers are synthetized through a finite dimensional model, derived from a finite element analysis of the mechanical structure, combined with some reduction methods.The flexible structures considered here are, firstly, aflexible aluminium beam in the Euler-Bernoulli configuration,and secondly, an axysimmetric membrane. Bothof them are equipped with two piezoelectric patches that are bounded and collocated on each face of the structure.We intend to examine and discuss the aforementioned performances in both simulation and experimental environments
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Feng, Yu. "Commande H2 - H∞ non standard des systèmes implicites." Phd thesis, Ecole des Mines de Nantes, 2011. http://tel.archives-ouvertes.fr/tel-00678501.

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Les systèmes implicites (dits aussi " descripteurs ") peuvent décrire des processus régis à la fois par des équations dynamiques et statiques et permettent de préserver la structure des systèmes physiques. Ils comportent trois types de modes : dynamiques finis, infinis (réponse temporelle impulsive (en cas continu) ou acausale (en cas discret)) et statiques. Dans le cadre du formalisme descripteur, les contributions de cette thèse sont triples : i) revisiter des résultats existants pour les systèmes d'état, ii) étendre certains résultats classiques au cas des systèmes implicites, iii) résoudre rigoureusement des problèmes de commande non standard. Ainsi, le présent mémoire commence par revisiter les résultats concernant la caractérisation LMI stricte de la dissipativité, les caractérisations de l'admissibilité et des performances H2 ou H∞ par LMI étendues et les équations de Sylvester et de Riccati généralisées. Il aborde dans un deuxième temps, le problème de stabilisation simultanée, avec ou sans critère H∞, à travers l'extension de certains résultats récents au cas des systèmes implicites. La solution proposée s'appuie sur la résolution combinée d'une équation algébrique de Riccati généralisée (GARE) et d'un problème de faisabilité sous contrainte LMI stricte. Il traite enfin des problèmes H2 et H∞ non standards : i) en présence de pondérations instables voire impropres, ii) sous contraintes de régulation; dans le cas des systèmes implicites. Ces dernières contributions permettent désormais de traiter rigoureusement, sans approximations ou transformations, de nombreux problèmes H2 ou H∞ formalisant des problèmes pratiques de commande, dont ceux faisant intervenir une pénalisation haute fréquence de la commande ou un modèle interne instable des signaux exogènes.
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Libros sobre el tema "Command H∞"

1

Cassidy, Duane H. General Duane H. Cassidy, Commander in Chief United States Transportation Command and Commander in Chief Military Airlift Command: An oral history : Air Force joint and business careers. USTRANSCOM Office of History, 1998.

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K, Matthews James, Holt Cora J, and United States. Transportation Command. Office of History., eds. General Duane H. Cassidy, United States Transportation Command's first commander in chief: An oral history. USTRANSCOM Office of History, 1990.

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3

Simon, John Y. Grant and Halleck: Contrasts in command. Marquette University Press, 1996.

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4

Little Phil: A reassessment of the Civil War leadership of Gen. Philip H. Sheridan. Brassey's, 2002.

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Office, General Accounting. Navy relocation: Transfer of the Naval Explosives Development Engineering Department : briefing report to the Honorable Herbert H. Bateman, House of Representatives. The Office, 1989.

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Office, General Accounting. Navy relocation: Transfer of the Naval Explosives Development Engineering Department : briefing report to the Honorable Herbert H. Bateman, House of Representatives. The Office, 1989.

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Europe, United States Congress House Committee on International Relations Subcommittee on. To commend Turkey and Israel for continuing to strengthen their partnership and support of the war on terrorism; to express the sense that security, reconciliation, and prosperity for all cypriots can be best achieved within membership of the EU and for other purposes; to commend Turkey for assuming command of the peacekeeping operation in Afghanistan: Markup before the Subcommittee on Europe of the Committee on International Relations, House of Representatives, One Hundred Seventh Congress, second session on H. Cong. Res. 327, H. Con. Res. 164 and H. Con. Res. 437. U.S. G.P.O., 2002.

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Backus, Paul H. The reminiscences of Commander Paul H. Backus, U.S. Navy (retired). U.S. Naval Institute, 1995.

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Bunnell, David C. The travels and adventures of David C. Bunnell: During twenty-three years of a sea-faring life, containing an accurate account of the battle on Lake Erie under the command of Com. Oliver H. Perry ... also service among the Greeks, imprisonment among the Turks, &c. &c. J.H. Bortles, 1986.

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Jellamo, Anna. Interpretazione del bene comune: Saggio su Thomas H. Green. Giuffrè, 1993.

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Capítulos de libros sobre el tema "Command H∞"

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Hyde, Richard Alden. "Flight Control Modes and Command Precompensation." In H∞ Aerospace Control Design. Springer London, 1995. http://dx.doi.org/10.1007/978-1-4471-3049-9_12.

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Thompson, Noel. "The Structure of the Commune." In G. D. H. Cole: Selected Works. Routledge, 2022. http://dx.doi.org/10.4324/9780203839317-56.

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Thompson, Noel. "The Working of the Commune." In G. D. H. Cole: Selected Works. Routledge, 2022. http://dx.doi.org/10.4324/9780203839317-57.

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Chrystal, K. Alec. "Comment on Patricia H. Werhane." In The Ethical Dimension of Financial Institutions and Markets. Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-79723-1_8.

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McKinlay, A. Craig. "Comment on Patricia H. Werhane." In The Ethical Dimension of Financial Institutions and Markets. Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-79723-1_9.

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Dimova-Cookson, Maria. "Green’s Theory of the Common Good." In T. H. Green’s Moral and Political Philosophy. Palgrave Macmillan UK, 2001. http://dx.doi.org/10.1057/9780230509542_4.

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Bornstein, Marc H., Diane L. Putnick, Joan T. D. Suwalsky, et al. "Neurobiology of Culturally Common Maternal Responses to Infant Cry." In Parenting: Selected Writings of Marc H. Bornstein. Routledge, 2022. http://dx.doi.org/10.4324/9781003167570-19.

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Baumeler, Ämin, Julien Degorre, and Stefan Wolf. "Bell Correlations and the Common Future." In STEAM-H: Science, Technology, Engineering, Agriculture, Mathematics & Health. Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-74971-6_18.

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Newell, D. G. "The Pathogenic Mechanisms of H. pylori — a Comment." In Helicobacter pylori, Gastritis and Peptic Ulcer. Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75315-2_19.

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Houston, Gail Turley. "MP Sir Stafford H. Northcote, Speech, Commons sitting." In Hunger and Famine in the Long Nineteenth Century. Routledge, 2022. http://dx.doi.org/10.4324/9780429198076-74.

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Actas de conferencias sobre el tema "Command H∞"

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Yang, Changwei, and Jinwen An. "QFT/H ∞ robust mixed sensitivity control of command tracking system for space vehicle." In Second International Conference on Spatial Information Technology, edited by Cheng Wang, Shan Zhong, and Jiaolong Wei. SPIE, 2007. http://dx.doi.org/10.1117/12.775235.

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Lopez, J., R. Dormido, J. P. Gomez, S. Dormido, and J. M. Diaz. "Comparison of H∞ with QFT applied to an altitude command tracker for an UAV." In European Control Conference 2007 (ECC). IEEE, 2007. http://dx.doi.org/10.23919/ecc.2007.7068482.

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Qiu, Hongchu, Qin Zhang, John F. Reid, and Duqiang Wu. "Nonlinear Feedforward-Plus-PID Control for Electrohydraulic Steering Systems." In ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-0774.

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Abstract This paper presents the development of a nonlinear feedforward-plus-Proportional-Integral-Derivative (FPID) controller for electrohydraulic (E/H) steering on wheel-type tractors. An E/H steering system is a typical nonlinear system with deadband, saturation, asymmetric flow gain, time delay, and other nonlinear behaviors. Conventional PID controllers are incapable of achieving accurate steering control effectively on such nonlinear systems. In this research, an FPID controller was developed for effective and accurate steering control. The feedforward loop in this controller was designed to compensate for the deadband of the E/H system. The PID loop was designed to compensate the tracking error in steering control. A coordinated nonlinear gain function was designed to change the PID loop gain based on the level of the tracking error. This FPID controller has significantly improved the steering accuracy comparing with that from a PID controller. Test results showed that the maximum tracking error in steering angle was less than 0.5° corresponding to a sinusoid steering command of ±5° at the command frequency of 0.1 Hz. The maximum overshoot was less than 12% and the rise time was less than 0.25 s corresponding to a steering command of 5° step input. This FPID controller achieved effective and accurate steering control on agricultural tractor E/H steering systems.
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Gadewadikar, J., F. Lewis, K. Subbarao, and Ben M. Chen. "Design of H∞ command and control loops for unmanned aerial vehicles using static output-feedback." In 2007 46th IEEE Conference on Decision and Control. IEEE, 2007. http://dx.doi.org/10.1109/cdc.2007.4434065.

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Wang, Chaoyang, Yiwen Liu, Ming Liu, Daotong Chong, and Junjie Yan. "Influences of Load Command Signals on the Operation Characteristics of Coal-Fired Power Plants During Loading up Processes." In ASME 2017 Power Conference Joint With ICOPE-17 collocated with the ASME 2017 11th International Conference on Energy Sustainability, the ASME 2017 15th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2017 Nuclear Forum. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/power-icope2017-3422.

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In recent years an increasing number of coal-fired power plants are forced to take part in load cycling to balance the electricity demands and supplies in China. Therefore, the investigation of energy consumption characteristics of power plants during transient processes is necessary and valuable. In this paper, the loading up processes of a power plant with several formats of load commands, such as linear, parabolic, sine and exponential functions were simulated, and the energy consumption characteristics of the power plant were presented. Furthermore, the operation characteristics including flexibility, safety and generation cost were compared. Results show that: when the unit increases load with the same average cycling loading rate, the max difference of standard coal consumption rates is 1.03 g/(kW h), which decreases with the increase of average cycling rate. The excellent signal formats have the following features: the instantaneous cycling rates are small in the ending of a transient process while they have high values in the beginning and mid-stage of the process. (CSPE)
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Müllhäuser, Mario, and Jeff Lusardi. "US-German Joint In-flight and Simulator Evaluation of Collective Tactile Cueing for Torque Limit Avoidance - Shaker vs. Soft Stop." In Vertical Flight Society 76th Annual Forum & Technology Display. The Vertical Flight Society, 2020. http://dx.doi.org/10.4050/f-0076-2020-16401.

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The demonstration and testing of tactile cueing is the subject of a common research undertaking by the U.S. Army Combat Capabilities Development Command Aviation &amp; Missile Center (CCDC AvMC) and the German Aerospace Center (DLR). The primary objective was to test a torque protection system with both a stick shaking cue generated with an attachable stick shaker and a soft stop cue generated by an active inceptor system. It was tested by five pilots in flight on the RASCAL JUH-60A helicopter and by four pilots in the ground-based simulator of the ACT/FHS (H-135) research helicopter based on a common set of high performance takeoff mission profiles. The qualitative evaluation showed that the soft stop provided a greater workload reduction than the shaker and was the preferred cue. However, a shaker cue is a promising alternative when the application of an active inceptor system is not possible.
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Alam, Md Moktadir, Soichi Ibaraki, Koki Fukuda, Sho Morita, and Hiroshi Usuki. "Identification of a Kinematic Model of a 6DOF Industrial Manipulator With Angular Positioning Deviation “Error Map” of Rotary Axes." In 2020 International Symposium on Flexible Automation. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/isfa2020-9655.

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Abstract To improve the overall “absolute” positioning accuracy for the industrial manipulator, it is indispensable to calibrate its kinematic parameters. In conventional studies, researchers have focused on Denavit–Hartenberg (D-H) parameters. However, until now, for industrial manipulators, the absolute accuracy is significantly poor than its repeatability. In this study, we propose a new kinematic model of a 6DOF (degrees of freedom) industrial manipulator with the angular positioning deviation “error map” of each rotary axis. The angular positioning deviation is modeled as a function of command angular positions, as well as the rotation direction to model the influence of backlash. We also propose a method to identify the angular positioning deviation of all the rotary axes by using a laser tracker.
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Chan, K. S., J. D. Ye, P. Parkinson, et al. "Structural and optical properties of H implanted ZnO." In 2012 Conference on Optoelectronic and Microelectronic Materials & Devices (COMMAD). IEEE, 2012. http://dx.doi.org/10.1109/commad.2012.6472439.

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De Oliveira, Alice, and Michèle Lavagna. "Robust Control Design via Structured H-infinity for the Atmospheric Re-entry of Reusable Launchers." In ESA 12th International Conference on Guidance Navigation and Control and 9th International Conference on Astrodynamics Tools and Techniques. ESA, 2023. http://dx.doi.org/10.5270/esa-gnc-icatt-2023-191.

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The controlled atmospheric re-entry associated with the precision soft-landing of Reusable Launch Vehicles (RLVs) on Earth is very challenging as it depends on multiple parameters [1]. Over the last decade, the cost-effectiveness of such a technology has been finally demonstrated with the successful recoveries of SpaceX’s Falcon 9 first-stage rocket first [2], then followed by other companies such as the Rocket Lab’s Electron micro-launcher [3]. This breakthrough has been made possible by the development of advanced and robust computational methods able to generate in real time the flight conditions and to command the optimal vehicle's deflections accordingly to achieve a safe pinpoint landing. Indeed, during an Earth atmospheric re-entry, the vehicle is subjected to fast system dynamics changes partly induced by external loads associated with the terrestrial environment (e.g., lift, drag, wind and gusts), but also by the actuation commands to answer the landing constraints satisfaction and the vehicle integrity preservation. All those involve uncertainties and nonlinearities, which lead to vehicle’s instability and therefore give reason why for a highly performant Guidance, Navigation and Control system implementation [4]. More particularly, one of the critical aspects is the design of a robust control strategy capable of counteracting the previously defined disturbances and uncertainties while satisfying the strict accuracy requirements associated with the pinpoint landing [5]. As demonstrated by the current state-of-the-art on control design for launchers [6-7], the classical linear control theory represents a rich heritage with a lot of applications. This choice was motivated by its relative easiness of implementation and the possibility to use gain-scheduling techniques to adapt to nonlinear systems. Nevertheless, these techniques are well-adapted to the control system design of single-input single-output systems, such as for example a reusable rocket using a Thrust Vector Control (TVC) system as the unique actuator. The implementation of multiple-input multiple-output control systems becomes then complex since every channel is addressed in a single-loop fashion. This capability is however required for the future generation of reusable rocket, using also aerodynamic steering based on fins in addition to the TVC system for enhancing control authorities. Moreover, model uncertainties are not accurately considered in the design process, developed only with nominal conditions and stability margin requirements. For all these reasons, it results in an extensive (both in terms of time and cost) Verification and Validation campaign with many iterations and Monte-Carlo analyses to assess the performance and robustness of the control system. To overcome these drawbacks, the H-infinity family of methods, introduced a few years ago [8], provides with a powerful solution for robust control design. It relies on defining the control requirements in the frequency domain in terms of weighting functions and minimising the maximum gain of the resulting weighted system from the exogenous inputs to the outputs to be controlled. Moreover, the control-plant interaction is modelled through a Linear Fractional Transformation (LFT) representing the feedback action. Finally, the structured H-infinity method [9] allows to directly impose a specific control structure – like a Proportional-Integral-Derivative (PID), enabling the re-use of gain-scheduling techniques – and to consider parametric uncertainties for enhanced robustness. This paper studies the synthesis of a robust control system via structured H-infinity for the RLV atmospheric re-entry problem. First, the nonlinear 6-Degree-of-Freedom (6-DoF) RLV re-entry dynamics are simplified into a linear model and then linearised along a reference trajectory to get the nominal LFT of the system, then augmented with parametric uncertainties. The model covers the atmospheric re-entry and vertical landing of a first-stage rocket equipped with a TVC system and steerable planar fins. The controllers are built at different points of the re-entry trajectory, using the structured H-infinity framework through PID-like structures. Weighting functions considering the control objectives and requirements of a realistic RLV re-entry scenario are implemented. A robust stability analysis of the obtained system is performed via classical stability margins and structured singular value. Finally, the controllers are gain-scheduled and validated via Monte-Carlo analyses, using a nonlinear 6-DoF RLV re-entry dynamics simulator equipped with successive convex optimisation guidance. The performance of the resulting guidance and control architecture is compared with the baseline developed in previous works [10], using a TVC system only and classical linear feedback control through gain-scheduled PID controllers. This study lies within the ASCenSIon (Advancing Space Access Capabilities - Reusability and Multiple Satellite Injection) project, an innovative training network funded within H2020. References: [1] L. Blackmore, “Autonomous Precision Landing of Space Rockets”, The Bridge on Frontiers of Engineering, Vol. 4, No. 46, pp. 15–20 (2016). [2] M. Wall, “Wow! SpaceX Lands Orbital Rocket Successfully in Historic First”, SPACE.com (2015). Retrieval Date: 20-Jan-2022. URL: https://www.space.com/31420-spacex-rocket-landing-success.html [3] Rocket Lab (2017). “Rocket Lab Electron 'Its a Test' flight successfully makes it to space”. Retrieval Date: 20-Jan-2022. URL: https://www.rocketlabusa.com/updates/rocket-lab-successfully-makes-it-to-space-2/ [4] P. Simplício, A. Marcos, and S. Bennani. “Reusable Launchers: Development of a Coupled Flight Mechanics, Guidance, and Control Benchmark", Journal of Spacecraft and Rockets, Vol. 57, No. 1, pp. 74-89 (2020). [5] Marco Sagliano et al. “Robust Control for Reusable Rockets via Structured H-infinity Synthesis”. In: Proceedings of the 11th International ESA Conference on Guidance, Navigation &amp; Control Systems. Virtual Event, 22-25 June 2021. [6] C. Roux and I. Cruciani, “Scheduling Schemes and Control Law Robustness in Atmospheric Flight of VEGA”. In: Proceedings of the 7th International ESA Conference on Guidance, Navigation and Control Systems. Tralee, County Kerry, Ireland 2-5 June 2008. [7] Erwin Mooij. Linear Quadratic Regulator Design for an Unpowered, Winged Re-entry Vehicle (Series 08 - Astrodynamics and Satellite Systems, No 3). Delft University Press, 1998. ISBN: 9040715971. [8] J. C. Doyle, K. Glover, P. P. Khargonekar, and B. A. Francis, “State-space Solutions to Standard H2 and H∞ Control Problems,” IEEE Transactions on Automatic Control, vol. 34, no. 8, pp. 831–847, 1989. [9] P. Apkarian and D. Noll, “Nonsmooth H∞ Synthesis,” IEEE Transactions on Automatic Control, vol. 51, no. 1, pp. 71–86, 2006. [10] Alice De Oliveira and Michèle Lavagna. “Reusable Launchers Re-entry Controlled Dynamics Simulator”. In: Proceedings of the 9th European Conference for Aeronautics and Aerospace Sciences. Lille, France, 27th June - 1st July 2022.
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Nixon, Steven, Mike Augustin, Dennis Dunaway, and Dy Le. "Boiling Down Aviation Data: Development of the Aviation Data Distillery." In Vertical Flight Society 77th Annual Forum & Technology Display. The Vertical Flight Society, 2021. http://dx.doi.org/10.4050/f-0077-2021-16847.

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Army Aviation is one of the heaviest data consumers of all service branches, and is heavily reliant upon consistent data streams. Currently, a complex web of information systems contains the various pieces of data, which hinders not only the use of the existing data systems, but also the development of cutting-edge data consumers. The AVX Aircraft Company, under the direction of the U.S. Army Combat Capabilities Development Command Aviation and Missile Center, assembled a team from industry and academia with uniquely complimentary skills to prototype and showcase a centralized data analysis space and toolset. Team members from the Applied Research Laboratory at Penn State University developed a cloud-hosted integration environment, granting secure and compliant access to a variety of developers and other interested parties. PeopleTec, Inc. curated a comprehensive dataset from six different H-60 Blackhawk helicopters, including health and usage monitoring data, maintenance records, and flight recorder data. Researchers from the Institute for Materials, Manufacturing, and Sustainment at Texas Tech University set to work developing statistical data combinations and reductions, as well as interactive and novel visualizations of the above data and results. The final cloud-hosted toolset demonstrated the overwhelming value of the additional analysis capabilities a centralized data access portal could present to Army Aviation. The ability to rapidly draw conclusions from the alignment, refinement, and display of what are currently disparate data sources represents a massive opportunity to enhance the capability and reliability of units across U.S. Army Aviation.
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Informes sobre el tema "Command H∞"

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Melloni, Gian. Local Government Leadership in Sanitation and Hygiene: Experiences and Learnings from West Africa. Institute of Development Studies (IDS), 2022. http://dx.doi.org/10.19088/slh.2022.001.

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Between July and October 2021, the Sanitation Learning Hub worked with government representatives and development partners to develop, share, and cross-analyse case studies looking at local system and government strengthening in four local government areas across West Africa: Benin (N’Dali commune), Ghana (Yendi municipal district), Guinea (Molota commune), and Nigeria (Logo LGA). The initiative focused on examples of local leadership in sanitation and hygiene (S&amp;H), with case studies developed in collaboration with development partners (Helvetas in Benin, UNICEF in Ghana and Guinea, United Purpose in Nigeria) and the local governments they partner with. The goal was to cross-analyse examples of local government leadership in S&amp;H, looking at what led to the prioritisation of S&amp;H, and identifying commonalities and transferable knowledge through a participatory cross-learning process. The case studies identified positive change occurred in local government leadership in S&amp;H, and analysed the contributions to change, via document review, key informant interviews and focus group discussions. This learning brief shares the learnings and recommendations that emerged from the case studies and through the three participatory workshops that followed.
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Geisthardt, Eric, Burton Suedel, and John Janssen. Monitoring the Milwaukee Harbor breakwater : an Engineering With Nature® (EWN®) demonstration project. Engineer Research and Development Center (U.S.), 2021. http://dx.doi.org/10.21079/11681/40022.

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The US Army Corps of Engineers (USACE) maintains breakwaters in Milwaukee Harbor. USACE’s Engineering With Nature® (EWN®) breakwater demonstration project created rocky aquatic habitat with cobbles (10–20 cm) covering boulders (6–8 metric tons) along a 152 m section. A prolific population of Hemimysis anomala, an introduced Pontocaspian mysid and important food source for local pelagic fishes, was significantly (p &lt; .05) more abundant on cobbles versus boulders. Food-habits data of alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax) provided evidence that H. anomala were a common prey item. Night surveys and gill netting confirmed O. mordax preferred foraging on the cobbles (p &lt; .05) and consumed more H. anomala than at the reference site (p &lt; .05). H. anomala comprised a significant portion of the diets of young-of-the-year (YOY) yellow perch (Perca flavescens), YOY largemouth bass (Micropterus salmoides), and juvenile rock bass (Ambloplites rupestris) caught on the breakwater. The natural features’ construction on the breakwater increased the available habitat for this benthopelagic macroinvertebrate and created a novel ecosystem benefiting forage fish and a nursery habitat benefiting nearshore game fish juveniles. These data will encourage the application of EWN concepts during structural repairs at other built navigation infrastructure.
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Keller, Michael W. DTPH56-14-H-CAP01 Patch and Full-Encirclement Repairs for Through-Wall Defects. Pipeline Research Council International, Inc. (PRCI), 2016. http://dx.doi.org/10.55274/r0012087.

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The objective of the research presented in this report was to investigate the performance of patch-type composite repairs on pressure vessels with through-wall defects. The most common repair geometry for bonded composites is the full-encirclement repair where the repair is formed by installing a composite that completely encircles the damaged substrate. These repairs are straightforward to install and have proven to have good field performance through a variety of industry and academic-sponsored research projects. When the substrate vessel becomes large, then these encirclement repairs begin to become cumbersome and costly to install. A potential alternative is to use, instead, an adhesively bonded patch that does not encircle the substrate. Patch-type repairs have been used for almost two decades in the aerospace industry, but are not a common or accepted repair type for pressure vessels. The primary goal of the research in the present study was to understand the differences between full-encirclement and patch repairs on through-wall defects.
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Barg, Rivka, Kendal D. Hirschi, Avner Silber, Gozal Ben-Hayyim, Yechiam Salts, and Marla Binzel. Combining Elevated Levels of Membrane Fatty Acid Desaturation and Vacuolar H+ -pyrophosphatase Activity for Improved Drought Tolerance. United States Department of Agriculture, 2012. http://dx.doi.org/10.32747/2012.7613877.bard.

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Background to the topic: In previous works we have shown that Arabidopsis and tomato over-expressing H+-pyrophosphatase show increased tolerance to drought imposed by withholding irrigation of young plants in pots (Park et al. 2005). In addition, young tobacco plants over-expressing fatty acid desaturase 3 (OEX-FAD3) also showed increasing tolerance to drought stress (Zhang et al 2005), and similarly OEX-FAD3 young tomato plants (unpublished data from ARO), hence raising the possibility that pyramiding the two could further improve drought tolerance in tomato. Based on these findings the specific objects originally set were: 1. To analyze the impact of pyramiding transgenes for enhanced fatty acid desaturation and for elevated H+-PPase activity on tomato yielding under water deficit stress conditions. 2. To elucidate the biochemical relationship between elevated desaturation of the membrane lipids and the activities of selected vacuolar transporters in the context of drought responses. 3. To explore the S. pennellii introgression lines as alternative genetic sources for drought tolerance related to enhanced fatty acid desaturation and/or H+-PPase activity. 4. Since OEX-FAD3 increases the levels of linolenic acid which is the precursor of various oxylipins including the stress hormone Jasmonate. (JA), study of the effect of this transgene on tolerance to herbivore pests was added as additional goal. The Major conclusions, solutions, and achievements are: (1) The facts that ectopic over-expression of vacuolarH+-PPases (in line OEX-AVP1) does not change the fatty acid profile compared to the parental MoneyMaker (MM) line and that elevated level of FA desaturation (by OEX-FAD3) does not change the activity of either H+-PPase, H+-ATPaseor Ca2+ /H+ antiport, indicate that the observed increased drought tolerance reported before for increase FA desaturation in tobacco plants and increased H+PPase in tomato plants involves different mechanisms. (2) After generating hybrid lines bringing to a common genetic background (i.e. F1 hybrids between line MP-1 and MM) each of the two transgenes separately and the two transgenes together the effect of various drought stress regimes including recovery from a short and longer duration of complete water withhold as well as performance under chronic stresses imposed by reducing water supply to 75-25% of the control irrigation regime could be studied. Under all the tested conditions in Israel, for well established plants grown in 3L pots or larger, none of the transgenic lines exhibited a reproducible significantly better drought tolerance compare to the parental lines. Still, examining the performance of these hybrids under the growth practices followed in the USA is called for. (3) Young seedlings of none of the identified introgression lines including the S. pennellii homologs of two of the H+-PPase genes and one of the FAD7 genes performed better than line M82 upon irrigation withhold. However, differences in the general canopy structures between the IL lines and M82 might mask such differences if existing. (4). Over-expression of FAD3 in the background of line MP-1 was found to confer significant tolerance to three important pest insects in tomato: Bordered Straw (Heliothis peltigera), Egyptian cotton leafworm (Spodoptera littoralis) and Western Flower Thrips (Frankliniella occidentalis). Implications: Although the original hypothesis that pyramiding these two trasgenes could improve drought tolerance was not supported, the unexpected positive impact on herbivore deterring, as well as the changes in dynamics of JA biosynthesis in response to wounding and the profound changes in expression of wound response genes calls for deciphering the exact linolenic acid derived signaling molecule mediating this response. This will further facilitate breeding for herbivore pest and mechanical stress tolerance based on this pathway.
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Leonid E. Zakharov. Comment on "Wall Forces Produced During ITER Disruptions" by H. R. Strauss, R. Paccagnella, and J. Breslau (PHYSICS OF PLASMAS 17, 082505 (2010). Office of Scientific and Technical Information (OSTI), 2010. http://dx.doi.org/10.2172/1001196.

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Leonid E. Zakharov. Comment on "Wall Forces Produced During ITER Disruptions" by H. R. Strauss, R. Paccagnella, and J. Breslau (PHYSICS OF PLASMAS 17, 082505 (2010). Office of Scientific and Technical Information (OSTI), 2010. http://dx.doi.org/10.2172/1001658.

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Bass, Rachel, and Stephen Peggs. Comprehensive tracking study for the H-dipoles and common magnets in the splitter sections of the Cornell/Brookhaven Energy-Recovery-Linac Test Accelerator. Office of Scientific and Technical Information (OSTI), 2017. http://dx.doi.org/10.2172/1475155.

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Sanabria, Johana, Ginna Quiroga, Cindy Mejía, Erika Grijalba, and Martha Goméz. Effect of abiotic factors on viability and characterization of Metarhizium rileyi Nm017. Corporación colombiana de investigación agropecuaria - AGROSAVIA, 2019. http://dx.doi.org/10.21930/agrosavia.poster.2019.18.

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The species Chloridea virescens and Helicoverpa zea (Lepidoptera: Noctuidae) are declared agricultural pests with a high economic impact worldwide (Angulo et al. 2008). They are widely distributed on the American continent, and agrochemical are the most common method to control, which can cause environmental, social, economic and public impacts. A strain of Metarhizium rileyi Nm017 [AGROSAVIA - Orinoquia area (Col.)], demonstrated an e cacy of 75.8% on C. virescens, and 92.5% on H. zea on laboratory conditions. Mass production and virulence of Metarhizium sp. are susceptible to stress conditions such as temperature, UVB radiation and pH, a ecting conidial vigor, germination, and sporulation (Rangel et al. 2008, Oliveira et al. 2016). Likewise, the culture medium can a ect the infection processes measured through hydrophobicity and enzymatic activities (Ortiz 2013). The identi cation of these parameters allows selecting the most favorable conditions for its production and the challenges that must be assumed in downstream processes.
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O'Connell, Kelly, David Burdick, Melissa Vaccarino, Colin Lock, Greg Zimmerman, and Yakuta Bhagat. Coral species inventory at War in the Pacific National Historical Park: Final report. National Park Service, 2024. http://dx.doi.org/10.36967/2302040.

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The War in the Pacific National Historical Park (WAPA), a protected area managed by the National Park Service (NPS), was established "to commemorate the bravery and sacrifice of those participating in the campaigns of the Pacific Theater of World War II and to conserve and interpret outstanding natural, scenic, and historic values on the island of Guam." Coral reef systems present in the park represent a vital element of Guam?s cultural, traditional, and economical heritage, and as such, are precious and in need of conservation. To facilitate the management of these resources, NPS determined that a scleractinian (stony coral) species survey was necessary to establish a baseline for existing coral communities and other important factors for conservation. EnviroScience, Inc. performed a survey of stony coral species, coral habitat, and current evidence of stressors at WAPA?s H?gat and Asan Units in 2022. This report summarizes these findings from a management perspective and compares its findings to previous survey data from 1977 and 1999 (Eldridge et al. 1977; Amesbury et al. 1999). WAPA is located on the tropical island of Guam, located on the west-central coast of the island, and encompasses 2,037 acres. Underwater resources are a significant component of the park, as 1,002 acres consists of water acres. The park is comprised of seven units, of which two of these, the H?gat and Asan Beach Units, include all the oceanic water acres for the park. The H?gat Beach Unit (local spelling, formerly known as ?Agat?) is located at the south-west portion of the park and consists of 38 land acres and 557 water acres (NPS 2003). The Asan Beach Unit consists of 109 acres of land and 445 water acres (NPS 2003). A current baseline for existing coral communities and other important factors for conservation necessitates the need for up-to-date data on the location, presence, relative abundance, and present health of corals. Park managers need this updated data to determine where and how to best focus conservation priorities and identify restoration opportunities. Management actions in park reef areas informed by this inventory included identifying locations where there were: high rates of sedimentation; high coral biomass; rare or threatened species, with a priority given to species endemic to Guam and listed as ?threatened? under the U.S. Endangered Species Act (ESA; Acropora globiceps, A. retusa, A. speciosa, and Seriatopora aculeata); coral persistence and decline, disease and/or nuisance species, including the crown-of-thorns starfish (Acanthaster cf. solaris, ?COTS?) and the sponge Terpios hoshinota; and bleached areas. All work carried out was in accordance with the NPS statement of work (SOW) requirements, which involved a quantitative inventory using both new and pre-existing transects. The resulting transects totaled 61 (including the four from the 1999 study), each measuring 50 meters in length and distributed across depths of up to 50 feet. Divers took photo-quadrat samples covering an area of approximately 9 m?, encompassing 50 photo-quadrats of dimensions 0.50 m x 0.36 m (n=50). The collective area surveyed across all 61 transects amounted to ~549 m?. Additionally, a qualitative search was conducted to enhance documentation of coral species that have limited distribution and might not be captured by transects, along with identifying harmful species and stressors. Timed roving diver coral diversity surveys were carried out at a total of 20 sites occurring within the waters of WAPA, including eight sites at the H?gat unit and 12 sites at the Asan unit. The findings from this report reveal significant disparities in benthic cover compositions between H?gat and Asan units. The H?gat unit exhibits high abundances of turf algae and unconsolidated sediment while the Asan beach unit presents a different scenario, with hard coral as the dominant benthic cover, followed closely by crustose coralline algae (CCA). The Asan unit is also more difficult to access from shore or boat relative to H?gat which provides that unit some protection from human influences. The Asan beach unit's prevalence of hard coral, CCA, and colonizable substrate suggests a more favorable environment for reef growth and the potential benefits of maintaining robust coral cover in the area. These distinct differences in benthic communities highlight the contrasting ecological dynamics and habitats of the two study areas. Across both H?gat and Asan beach unit transects, a total of 56 hard coral species were recorded from 27 genera, with 44 species recorded from the H?gat unit and 48 species recorded from the Asan unit. Of the four historical transects surveyed in the Asan unit from 1999, three experienced declines in percent coral cover (17.38-78.72%), while the fourth had an increase (10.98%). During the timed roving diver coral diversity surveys, a total of 245 hard coral species, including 241 scleractinian coral species representing 49 genera and 4 non-scleractinian coral species representing 4 genera were recorded. Uncertainties related to coral identification, unresolved boundaries between morphospecies, differences in taxonomists' perspectives, and the rapidly evolving state of coral taxonomy have significant implications for species determinations during coral diversity surveys. While the recent surveys have provided valuable insights into coral diversity in WAPA waters, ongoing taxonomic research and collaboration among experts will be essential to obtain a more comprehensive and accurate understanding of coral biodiversity in the region. Of the several ESA coral species that were searched for among the H?gat and Asan beach units, Acropora retusa was the only coral species found among quantitative transects (n=2) and A. globiceps was observed during coral diversity surveys. Acropora speciosa, which was dominant in the upper seaward slopes in 1977, is now conspicuously absent from all the surveys conducted in 2022 (Eldredge et al., 1977). The disappearance and reduction of these once-dominant species underscores the urgency of implementing conservation measures to safeguard the delicate balance of Guam's coral reefs and preserve the diversity and ecological integrity of these invaluable marine ecosystems. Other formerly common or locally abundant species were infrequently encountered during the diversity surveys, including Acropora monticulosa, A. sp. ?obtusicaulis?, A. palmerae, Stylophora sp. ?mordax?, Montipora sp. ?pagoensis?, and Millepora dichotoma. Significant bleaching-associated mortality was recorded for these species, most of which are restricted to reef front/margin zones exposed to moderate-to-high levels of wave energy. Sedimentation was present in both H?gat and the Asan units, though it was more commonly encountered in H?gat transects. While significant portions of the reef area within the WAPA H?gat unit are in poor condition due to a variety of stressors, some areas still hosted notable coral communities, which should be a potential focus for park management to prevent further degradation. There is a need for more effective management of point source pollution concerns, particularly when subpar wastewater treatment or runoff from areas with potential pollution or sediment-laden water is flowing from nearby terrestrial environments. Future monitoring efforts should aim to establish a framework that facilitates a deeper understanding of potential point source pollution incidents. This would empower park managers to collaborate with adjacent communities, both within and outside of park boundaries, to mitigate the localized impacts of pollution (McCutcheon and McKenna, 2021). COTS were encountered during transect surveys as well as in coral diversity surveys. including along the upper reef front/reef margin at site Agat-CS-2. The frequency of these observations, particularly in the WAPA H?gat unit and where stress-susceptible corals are already uncommonly encountered, raise concern about the ability of the populations of these coral species to recover following acute disturbance events, and calls in to question the ability of some of these species to persist in WAPA waters, and in Guam?s waters more broadly. More frequent crown-of-thorns control efforts, even if only a handful of sea stars are removed during a single effort, may be required to prevent further loss to vulnerable species. There were several documented incidents of Terpios hoshinota covering large sections of branching coral in the reef flat along transects, but it is still unclear how detrimental this sponge is to the overall reef system. There is a concern that elevated levels of organic matter and nutrients in the water, such as those resulting from sewage discharge or stormwater runoff, could lead to increased Terpios populations (De Voogd et al. 2013). Consequently, it is important to track populations in known areas of sedimentation and poor water quality. The presence of unique species at single survey sites within the study areas underscores the ecological importance of certain locations. Some species are known to occur in other locations in Guam, while a few may be limited to specific sites within WAPA waters. These differences are likely influenced by environmental and biological factors such as poor water quality, severe heat stress events, chronic predation by crown-of-thorns sea stars, disease, and reduced herbivore populations. These factors collectively shape the condition of the benthic community, leading to variations in species distribution and abundance across the study sites. Documenting coral stress and identifying potentially harmful species allows for proactive management strategies to prevent the establishment of nuisance or detrimental species while populations are still manageable. Updated data on the location, presence, relative abundance, and health of corals is essential for park managers to prioritize conservation efforts and identify restoration opportunities effectively. Observations from this report raise concerns about the health and resilience of coral ecosystems in the H?gat unit and emphasize the need for knowledge of local factors that shape benthic community structure. Understanding the drivers responsible for these variations is crucial for effective conservation and management strategies to preserve the ecological balance and overall health of coral reefs in both units. Continued monitoring efforts will be critical in assessing long-term trends and changes in benthic cover and enabling adaptive management approaches to safeguard these valuable marine ecosystems in the face of ongoing environmental challenges.
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Pu, Fenglan, Tianli Li, Yingqiao Wang, Chunmei Tang, Chen Shen, and Jianping Liu. Cordyceps preparations for preventing contrast-induced nephropathy: A protocol of systematic review of randomized controlled trials. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, 2022. http://dx.doi.org/10.37766/inplasy2022.6.0098.

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Review question / Objective: To systematically evaluate the efficacy and safety of cordyceps preparations as a complementary preventive therapy for Contrast-induced nephropathy (CIN). Condition being studied: At present, contrast agents are widely used in diagnostic and interventional radiology examinations worldwide. However, they can affect kidney function and cause a risk of renal impairment. Contrast-induced nephropathy (CIN) is defined as a rise in serum creatinine (SCr) levels by ≥ 25% of baseline or 44 µmol/l from the pre-contrast value within 72 h of intravascular administration of a contrast agent in the absence of an alternative etiology. The incidence of CIN varies widely among studies depending on study population and baseline risk factors, as for high-risk groups such as pre-existing renal insufficiency, diabetes, advanced age, or receiving nephrotoxic agents, the incidence is up to 30–50%. To date, CIN has been the third most common cause of hospital-acquired renal failure, after impaired renal perfusion and nephrotoxic medications, which can lead to longer hospital stay, increased costs and higher mortality.
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