Commande prédictive hiérarchisée pour le positionnement des axes de machine-outil à architecture ouverte PDF Download

Author: Mara Susanu
Publisher:
ISBN:
Category :
Languages : fr
Pages : 210

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Book Description
Cette thèse propose une contribution à l'amélioration des performances des machines-outils à commande numérique en termes de précision, lors des phases de positionnement de l'outil pendant l'usinage de formes complexes. Pour cela, une structure de commande avancée hiérarchisée à trois niveaux est développée, exploitant la connaissance a priori de la trajectoire de l'outil. Un premier niveau, le plus proche de la machine, considère pour la commande d'axe une structure de commande prédictive avec une option de robustification par la paramétrisation de Youla vis-à-vis de bruits de mesure et d'incertitude sur les paramètres. Un deuxième niveau appelé superviseur de référence modifie de façon prédictive également les consignes axiales afin de minimiser l'impact de saturations des signaux de commande. Enfin, le troisième niveau, dit régénérateur de trajectoire, intervient avec un aspect anticipatif lorsque les consignes axiales modifiées s'éloignent trop des références initiales, pour recalculer la trajectoire spatiale.La stratégie mise en œuvre est conçue sous la forme générique à deux degrés de liberté dite RST, permettant à l'utilisateur d'implanter sa propre loi de commande par adjonction d'un module supplémentaire au sein d'un même formalisme. Cette architecture ouverte apporte une réponse innovante au besoin des commandes numériques actuellement limitées par le caractère fermé de la commande d'axe et du générateur de trajectoire.Afin de valider la structure, une machine-outil virtuelle a enfin été développée, permettant des tests comparatifs entre les stratégies de commande classiques et avancées. Le centre d'usinage Mikron UCP 710 sert de support à cette validation.

Author: Guy Ankerl
Publisher: INU PRESS
ISBN: 9782881550041
Category : History
Languages : en
Pages : 536

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Book Description
Some important questions are discussed in this book: Are there any civilisations other than the Western one living in our so-called Global-Age? 'Eastern civilisation'? Is the concept of East anything more than non-West? Or does there exist, in reality, a distinct Chinese, Indian, Arabo-Muslim, and Western civilisation? Is the construction of large civilisation-states such as China and India an unparalleled historical achievement? Do economic ties always eclipse other forms of affiliation such as those formed through kinship or between speech communities? What is the role of the 'Latin' and the Jewish Peoples in our Anglo-American-led Western world? Is English today the global language or merely an international one? Is the Chinese thought pattern closely related to its writing system? Is today's world one of (symmetrical) interdependence? Or rather one of hegemony? If the so-called North-South or East-West dialogue fails in constructing a universally accepted world civilisation, then what is the appropriate arrangement for reaching such a consensus within humankind?

Author: Claire Clivaz
Publisher:
ISBN: 9789004399655
Category : Bible
Languages : en
Pages : 0

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Ecritures digitales aims to demonstrate how digital writing, as new technology, contributes to the emergence of a reconfigured relationship between the human body and the machines, and how this transition influences the Jewish-Christian textual corpus referred to as "the Scriptures". Ecritures digitales souhaite démontrer de quelle manière l'écriture digitale, en tant que nouvelle technologie, contribue à l'émergence d'une relation innovante entre le corps humain et les machines, et influence le corpus textuel judéo-chrétien désigné comme «les Ecritures».

Author: International Atomic Energy Agency
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Author: Michel Godet
Publisher:
ISBN: 9782717852448
Category :
Languages : en
Pages : 0

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Author: Jean-Baptiste Say
Publisher: Taylor & Francis
ISBN: 1317912292
Category : Business & Economics
Languages : en
Pages : 290

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Book Description
Jean-Baptiste Say (1767–1832) was one of the first great economists to have laid down the foundations of economic science. Author of the famous Treatise on Political Economy in 1803, which was revised and re-edited on several occasions, he published numerous other works including a voluminous Complete Course in Practical Political Economy in 1828–9. He also taught political economy successively from 1815 until his death in three Parisian establishments: the Athénée, the Conservatory of Arts and Trades, and the Collège de France. The texts in which Say exposes his approach to political economy have not been available in the English language until now except for the fourth edition of the ‘Preliminary Discourse’ which serves as an introduction to the Treatise. This book presents a translation which renders his works accessible to the English speaking world. For the first time, English readers will be able to become directly immersed in Say’s principal texts, where he develops his conception of political economy. Jean-Baptiste Say and Political Economy proposes a translation of a selection of eleven of Say’s texts. The first three are versions of the ‘Preliminary Discourse’ from the Treatise’s editions of 1803, 1814 and 1826 with the variations of the editions of 1817, 1819 and 1841. The following four texts are the opening discourses pronounced at the Conservatory in 1820 and 1828 and the Collège de France in 1831 and 1832. The eighth text is the ‘General Considerations’ which open the Complete Course in Practical Political Economy of 1828, with the variations of the 1840 re-edition. The final three texts are those Say devotes to ‘the progress of political economy’ in what is akin to a history of economic thought. This volume is of great importance to economic historians and people studying Jean-Baptiste Say, as well as those who are interested in economic theory and philosophy and political economy.

Author: Xinyuan Wang
Publisher: UCL Press
ISBN: 191063462X
Category : Social Science
Languages : en
Pages : 238

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Book Description
Life outside the mobile phone is unbearable.’ Lily, 19, factory worker. Described as the biggest migration in human history, an estimated 250 million Chinese people have left their villages in recent decades to live and work in urban areas. Xinyuan Wang spent 15 months living among a community of these migrants in a small factory town in southeast China to track their use of social media. It was here she witnessed a second migration taking place: a movement from offline to online. As Wang argues, this is not simply a convenient analogy but represents the convergence of two phenomena as profound and consequential as each other, where the online world now provides a home for the migrant workers who feel otherwise ‘homeless’. Wang’s fascinating study explores the full range of preconceptions commonly held about Chinese people – their relationship with education, with family, with politics, with ‘home’ – and argues why, for this vast population, it is time to reassess what we think we know about contemporary China and the evolving role of social media.

Author: Geoffrey Nelson
Publisher: Palgrave Macmillan
ISBN: 9780333922828
Category : Psychology
Languages : en
Pages : 608

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Book Description
This is the first up-to-date text written specifically for the international market on psychology in the community. Community Psychology covers the history and foundations of the field, key concepts and values, community research, community action, and the application of psychology in various settings, integrating the values/politics and scientific/research aspects of community work. Written by experienced authors in the field, this text will be internationally invaluable.

Author: Alain Hébert
Publisher: Presses inter Polytechnique
ISBN: 2553014368
Category : Nuclear physics
Languages : en
Pages : 426

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Author: Robert E Hess
Publisher: Routledge
ISBN: 131777437X
Category : Psychology
Languages : en
Pages : 245

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Book Description
This adaptable book offers diverse applications of the empowerment model to the promotion of mental health and the prevention of mental illness. Topics span the developmental trends of empowerment as an individual achievement, a community experience, and a professional aim in relation to social intervention strategies and tactics.