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At the end of the 17th century the law of fluid resistance established by Newton gives the opportunity to apply mathematics to new physical and mechanical situations in very important fields on a economic and military point of views: marine, military arts and hydraulics. This opportunity however faces several obstacles. The first one is theoretical. The second one concerns the relations between the stakeholders, and requires to take into account the transformation of the status and role of one of them, the engineer, which may be able to develop bridges between theoreticians and artisans. During the second half of the 18th century, the fluid resistance raises several questions, one of which follows from the difficulties encountered, and concerns the usefulness of theory for practice. Panckoucke's Encyclopédie méthodique consisting in a reorganization per subject of the knowledge gathered in Diderot's and D'Alembert's Encyclopédie (1751-1765), the Dictionnaire de Mathématiques, published between 1784 and 1789, is thus an especially interesting work to deal with this question. Based on the study of fluid resistance and its applications, I will first emphasize the small place given to the mathematics applied to concrete problems, namely in marine and ballistics. I will show that this statement is not only due to the edition process of the dictionary, but also to the ideas of the editors (Bossut and Charles) on the usefulness of mathematics in practice.

At the end of the 17th century the law of fluid resistance established by Newton gives the opportunity to apply mathematics to new physical and mechanical situations in very important fields on a economic and military point of views: marine, military arts and hydraulics. This opportunity however faces several obstacles. The first one is theoretical. The second one concerns the relations between the stakeholders, and requires to take into account the transformation of the status and role of one of them, the engineer, which may be able to develop bridges between theoreticians and artisans. During the second half of the 18th century, the fluid resistance raises several questions, one of which follows from the difficulties encountered, and concerns the usefulness of theory for practice. Panckoucke's Encyclopédie méthodique consisting in a reorganization per subject of the knowledge gathered in Diderot's and D'Alembert's Encyclopédie (1751-1765), the Dictionnaire de Mathématiques, published between 1784 and 1789, is thus an especially interesting work to deal with this question. Based on the study of fluid resistance and its applications, I will first emphasize the small place given to the mathematics applied to concrete problems, namely in marine and ballistics. I will show that this statement is not only due to the edition process of the dictionary, but also to the ideas of the editors (Bossut and Charles) on the usefulness of mathematics in practice.

At the end of the 17th century the law of fluid resistance established by Newton gives the opportunity to apply mathematics to new physical and mechanical situations in very important fields on a economic and military point of views: marine, military arts and hydraulics. This opportunity however faces several obstacles. The first one is theoretical. The second one concerns the relations between the stakeholders, and requires to take into account the transformation of the status and role of one of them, the engineer, which may be able to develop bridges between theoreticians and artisans. During the second half of the 18th century, the fluid resistance raises several questions, one of which follows from the difficulties encountered, and concerns the usefulness of theory for practice. Panckoucke's Encyclopédie méthodique consisting in a reorganization per subject of the knowledge gathered in Diderot's and D'Alembert's Encyclopédie (1751-1765), the Dictionnaire de Mathématiques, published between 1784 and 1789, is thus an especially interesting work to deal with this question. Based on the study of fluid resistance and its applications, I will first emphasize the small place given to the mathematics applied to concrete problems, namely in marine and ballistics. I will show that this statement is not only due to the edition process of the dictionary, but also to the ideas of the editors (Bossut and Charles) on the usefulness of mathematics in practice.

At the end of the 17th century the law of fluid resistance established by Newton gives the opportunity to apply mathematics to new physical and mechanical situations in very important fields on a economic and military point of views: marine, military arts and hydraulics. This opportunity however faces several obstacles. The first one is theoretical. The second one concerns the relations between the stakeholders, and requires to take into account the transformation of the status and role of one of them, the engineer, which may be able to develop bridges between theoreticians and artisans. During the second half of the 18th century, the fluid resistance raises several questions, one of which follows from the difficulties encountered, and concerns the usefulness of theory for practice. Panckoucke's Encyclopédie méthodique consisting in a reorganization per subject of the knowledge gathered in Diderot's and D'Alembert's Encyclopédie (1751-1765), the Dictionnaire de Mathématiques, published between 1784 and 1789, is thus an especially interesting work to deal with this question. Based on the study of fluid resistance and its applications, I will first emphasize the small place given to the mathematics applied to concrete problems, namely in marine and ballistics. I will show that this statement is not only due to the edition process of the dictionary, but also to the ideas of the editors (Bossut and Charles) on the usefulness of mathematics in practice.

Le Manuel de rédaction à l'usage des militaires est un guide de rédaction qui s'adresse aux membres des forces armées appelés à rédiger des textes de qualité dans un style soutenu pour un lectorat militaire averti. Unique en son genre, il est une référence incontournable dans ce milieu.

Notice thèse accessible sur : http://www.theses.fr/2017EHES0045 ; International audience ; During the second half of the 20th century, attempts were made to operationally redefine various social activities, including those related to science, the military, administration and industry. These attempts were aided by scientific and technical innovations developed in the Second World War, and subsequently by the increase in use of automation in various domains. This Ph.D. thesis addresses these attempts from a sociohistorical perspective, focusing on the specific case of archaeology. During this period, the domain of archaeology underwent a process of disciplinarisation and professionalisation. The same occurred in applied mathematics and then computer science: this thesis focuses on the relationships between these three domains. In France, during the 1950's and 1960's, there were significant methodological and conceptual innovations. Their subsequent scientific recognition, was, however, relatively minor. In archaeology, innovations related to applied mathematics and automatics did not lead to the emergence of an archaeological speciality based on computation. This situation was in striking contrast to what happened in other scientific domains and in archaeology in other countries, where new theoretical and methodological Anglophone definitions in 'New Archaeology' were spreading worldwide. This thesis explores three collective attempts to redefine the conceptual and methodological basis of archaeology, led by Georges Laplace, Jean-Claude Gardin and Jean Lesage, across France, Spain and Italy. These cases are completed by other people who had significant careers in both engineering and archaeology. In general, this thesis studies a scientific activity by investigating the cognitive and social aspects of peoples' methodological contributions. Three models of the relationships between experts in a scientific domain and experts in an applied science (here mathematics and computing) are empirically identified and ...

Quelles raisons peuvent amener des chercheurs à plaider en faveur de l'introduction de méthodes jugées plus précises et systématiques mais se révélant aussi plus abstraites et contraignantes en pratique ? La question est examinée à partir des parcours de deux archéologues français, Georges Laplace et Jean-Claude Gardin. Dès les années 1950, ils se distinguent par leurs propositions méthodologiques fondées sur la formalisation ou le calcul. Elles restent toutefois relativement isolées au cours des décennies suivantes, alors même que des propositions similaires connaissent un succès en archéologie anglophone ou dans d'autres disciplines. Par une approche biographique on met en évidence les équivalences et les tensions établies entre les critères épistémiques et éthiques, biographiques et politiques qui caractérisent ces expériences, lesquelles apparaissent comme les formes les plus radicales d'une aspiration contemporaine à la modernisation et à la professionnalisation de l'archéologie. What are the reasons leading some researchers to advocate the application of certain methods on the ground that they are more precise and more systematic, even though they are also more abstract and more constraining than those currently in use? This question is examined here through a review of the evolution of the academic career of two French archaeologists, Georges Laplace and Jean-Claude Gardin. Their earliest works, dating from the 1950s, were characterized by the application of more abstract methodologies, based on formalization or on the use of computation. In the following decades, Laplace and Gardin's approach remained marginal in France, even though at the same time, similar perspectives were becoming popular not only among English-speaking archaeologists but also in other academic fields in France. The biographical perspective adopted in this paper allows us to highlight the parallel trajectories and the tensions existing between the epistemical, ethical, biographical, and political dimensions that shaped the careers of ...

What are the reasons leading some researchers to advocate the application of certain methods on the ground that they are more precise and more systematic, even though they are also more abstract and more constraining than those currently in use? This question is examined here through a review of the evolution of the academic career of two French archaeologists, Georges Laplace and Jean-Claude Gardin. Their earliest works, dating from the 1950s, were characterized by the application of more abstract methodologies, based on formalization or on the use of computation. In the following decades, Laplace and Gardin's approach remained marginal in France, even though at the same time, similar perspectives were becoming popular not only among English-speaking archaeologists but also in other academic fields in France. The biographical perspective adopted in this paper allows us to highlight the parallel trajectories and the tensions existing between the epistemical, ethical, biographical, and political dimensions that shaped the careers of Laplace and Gardin. As such, their academic experiences appear as the most radical forms of the contemporary aspiration to modernize and professionalize archaeology.

International audience ; Tartaglia's Nova Scientia published in 1537 heralded a new approach to the problems of military technology, by adopting neo-platonistic principles to physical phenomena. However, his enquiry was limited by his Aristotelian viewpoint, and his final edition of 1558 offered the idea that nature could be explained by knowledge applied through Platonic philosophy. Tartaglia had accepted that the flight of the missile, hitherto thought to comprise distinct violent and natural phases, had to be of a mixed nature. While application of mathematics in a mechanical paradigm offered a practical validity, readers needed convincing by a formal proof. The problem of the Gunner was finding a reliable way of firing his shot with reasonable accuracy. Neo-platonist philosophy needed a convincing solution to this problem. In his Stratioticos (1579) Thomas Digges' chapter on gunnery proposed an extensive list of parameters for investigation, thus offering an experimental programme for the English Gunners to follow over the next century. Some thoughts on learning in communities and epistemologies are considered

International audience ; What are the reasons leading some researchers to advocate the application of certain methods on the ground that they are more precise and more systematic, even though they are also more abstract and more constraining than those currently in use? This question is examined here through a review of the evolution of the academic career of two French archaeologists, Georges Laplace and Jean-Claude Gardin. Their earliest works, dating from the 1950s, were characterized by the application of more abstract methodologies, based on formalization or on the use of computation. In the following decades, Laplace and Gardin's approach remained marginal in France, even though at the same time, similar perspectives were becoming popular not only among English-speaking archaeologists but also in other academic fields in France. The biographical perspective adopted in this paper allows us to highlight the parallel trajectories and the tensions existing between the epistemical, ethical, biographical, and political dimensions that shaped the careers of Laplace and Gardin. As such, their academic experiences appear as the most radical forms of the contemporary aspiration to modernize and professionalize archaeology. ; Quelles raisons peuvent amener des chercheurs à plaider en faveur de l'introduction de méthodes jugées plus précises et systématiques mais se révélant aussi plus abstraites et contraignantes en pratique ? La question est examinée à partir des parcours de deux archéologues français, Georges Laplace et Jean-Claude Gardin. Dès les années 1950, ils se distinguent par leurs propositions méthodologiques fondées sur la formalisation ou le calcul. Elles restent toutefois relativement isolées au cours des décennies suivantes, alors même que des propositions similaires connaissent un succès en archéologie anglophone ou dans d'autres disciplines. Par une approche biographique on met en évidence les équivalences et les tensions établies entre les critères épistémiques et éthiques, biographiques et politiques qui caractérisent ces expériences, lesquelles apparaissent comme les formes les plus radicales d'une aspiration contemporaine à la modernisation et à la professionnalisation de l'archéologie.

International audience ; What are the reasons leading some researchers to advocate the application of certain methods on the ground that they are more precise and more systematic, even though they are also more abstract and more constraining than those currently in use? This question is examined here through a review of the evolution of the academic career of two French archaeologists, Georges Laplace and Jean-Claude Gardin. Their earliest works, dating from the 1950s, were characterized by the application of more abstract methodologies, based on formalization or on the use of computation. In the following decades, Laplace and Gardin's approach remained marginal in France, even though at the same time, similar perspectives were becoming popular not only among English-speaking archaeologists but also in other academic fields in France. The biographical perspective adopted in this paper allows us to highlight the parallel trajectories and the tensions existing between the epistemical, ethical, biographical, and political dimensions that shaped the careers of Laplace and Gardin. As such, their academic experiences appear as the most radical forms of the contemporary aspiration to modernize and professionalize archaeology. ; Quelles raisons peuvent amener des chercheurs à plaider en faveur de l'introduction de méthodes jugées plus précises et systématiques mais se révélant aussi plus abstraites et contraignantes en pratique ? La question est examinée à partir des parcours de deux archéologues français, Georges Laplace et Jean-Claude Gardin. Dès les années 1950, ils se distinguent par leurs propositions méthodologiques fondées sur la formalisation ou le calcul. Elles restent toutefois relativement isolées au cours des décennies suivantes, alors même que des propositions similaires connaissent un succès en archéologie anglophone ou dans d'autres disciplines. Par une approche biographique on met en évidence les équivalences et les tensions établies entre les critères épistémiques et éthiques, biographiques et ...

Notice thèse accessible sur : http://www.theses.fr/2017EHES0045 ; International audience ; During the second half of the 20th century, attempts were made to operationally redefine various social activities, including those related to science, the military, administration and industry. These attempts were aided by scientific and technical innovations developed in the Second World War, and subsequently by the increase in use of automation in various domains. This Ph.D. thesis addresses these attempts from a sociohistorical perspective, focusing on the specific case of archaeology. During this period, the domain of archaeology underwent a process of disciplinarisation and professionalisation. The same occurred in applied mathematics and then computer science: this thesis focuses on the relationships between these three domains. In France, during the 1950's and 1960's, there were significant methodological and conceptual innovations. Their subsequent scientific recognition, was, however, relatively minor. In archaeology, innovations related to applied mathematics and automatics did not lead to the emergence of an archaeological speciality based on computation. This situation was in striking contrast to what happened in other scientific domains and in archaeology in other countries, where new theoretical and methodological Anglophone definitions in 'New Archaeology' were spreading worldwide. This thesis explores three collective attempts to redefine the conceptual and methodological basis of archaeology, led by Georges Laplace, Jean-Claude Gardin and Jean Lesage, across France, Spain and Italy. These cases are completed by other people who had significant careers in both engineering and archaeology. In general, this thesis studies a scientific activity by investigating the cognitive and social aspects of peoples' methodological contributions. Three models of the relationships between experts in a scientific domain and experts in an applied science (here mathematics and computing) are empirically identified and described. The effects of introducing mathematical and automation procedures on the division of labour and the distribution of recognition are analysed. The success or failure of the methodological propositions are discussed with reference to several factors and models of scientific innovation. This thesis generates new information on the development of rescue and preventive archaeology and on the use of digital technologies in human sciences. The analysis draws on 82 interviews, 23 archives and several bibliometric datasets (extracted from pre-existing databases or constructed for the purpose of this research). Mirroring the archaeological propositions under study, this research also intends to illustrate the possible use of computing and formalised procedures in social sciences. The documentation and demonstrative principles underlying this work, implemented by using Wiki, the methods of literate programming and reproducible research, are themselves analysed. ; La seconde moitié du XXe siècle donna lieu à un accroissement des tentatives de redéfinir en termes opérationnels divers domaines de l'activité sociale tant scientifique, militaire, administratif ou industriel. Ces tentatives tirèrent parti des innovations scientifiques et techniques de la Deuxième Guerre mondiale, puis de la généralisation de l'automatique. Cette thèse en propose une sociologie historique, menée à partir du cas particulier de l'archéologie. Ce domaine scientifique fait alors l'objet d'efforts accrus de disciplinarisation et de professionnalisation. C'est également le cas des mathématiques appliquées puis de l'informatique : cette étude porte précisément sur les rapports établis à l'intersection de ces trois domaines. En France, au cours des années 1950 et 1960, les innovations méthodologiques et conceptuelles y ont été particulièrement importantes. Pourtant, par la suite, leur réception s'est révélée relativement mineure. En archéologie, les innovations relatives aux mathématiques appliquées, à la formalisation du langage et à l'automatique n'ont pas donné lieu au développement d'une spécialité fondée sur le calcul. Cette situation contraste avec celle d'autres disciplines ou d'autres pays, et ceci alors même que les redéfinitions théoriques et méthodologiques de la « New Archaeology » anglophone se diffusaient à l'échelle internationale. La thèse explore les cas de trois entreprises collectives, menées respectivement autour de Georges Laplace, Jean-Claude Gardin et Jean Lesage, entre France, Espagne et Italie. Ces cas sont complétés par ceux d'un ensemble d'acteurs ayant été à la fois ingénieurs et archéologues. D'un point de vue général, cette étude porte sur les statuts cognitifs et sociaux des contributions méthodologiques dans l'activité scientifique. Trois modèles de relations entre spécialistes d'un domaine scientifique et spécialistes des sciences formelles sont identifiés et décrits. Les transformations entraînées par l'introduction des mathématiques et de l'automatique dans la division du travail et la distribution des formes de reconnaissance sont analysées. La réception de ces propositions méthodologiques est discutée à l'aune de différents facteurs et modèles de l'innovation scientifique. Ce sont, au final, des éclairages nouveaux sur le développement de l'archéologie de sauvetage puis préventive et sur la genèse des recours aux technologies « numériques » en sciences de l'homme qui sont proposés. L'analyse tire parti de 82 entretiens, 23 fonds d'archives et de plusieurs jeux de données bibliométriques (pré-existants ou constitués pour cette étude). En écho aux travaux pris pour objets, cette thèse entend également être une proposition et une illustration d'un usage possible de la formalisation et de l'informatique en sciences sociales. Fondées sur l'emploi d'un wiki et les principes de la programmation lettrée et de la reproductibilité des analyses, les architectures documentaire et démonstrative de cette étude font elles-mêmes l'objet d'une analyse.

Joseph Kampé de Fériet (1893-1982), a French mathematician of Lille, was an international specialist in fluid mechanics and was director of the Institut de mécanique des fluides de Lille (IMFL) from its creation in 1929. By familiarizing himself with this field and by addressing questions of an experimental nature through his work on ballistics, during his scientific wartime service to the Gâvre Commission (1915-1919), this scientist played a triple role in the institute. As a mathematician, he made a remarkable contribution to Taylor-von Kármán's statistical theory of turbulence using the theory of random functions due to Kolmogorov, Khintchine, and Slutsky. As an experimental scientist, he took part in the experimental work of the IMFL aiming on one hand to study atmospheric turbulence and, on the other hand, to validate the ideas of the school of Philippe Wehrle and Georges Dedebant. This school was formed within the Atmospheric Turbulence Commission, created by the Minister of Air in 1935. Finally, as director of the institute, he strengthened links with industry and society in Lille, in the same way that he reinforced links with military officers during his work in Gâvre.In our thesis, we will use the scientific and institutional career path of J. Kampé de Fériet – from his service at Gâvre (1915) up until the year of his resignation as director of the IMFL (1945) - as a prism by which we will answer further questions of a more general nature regarding fluid mechanics in France during the first half of the twentieth century. Some but not all of these considerations bring to light new elements that are common to ballistics and to other areas of applied mathematics. ; Joseph Kampé de Fériet (1893–1982) est un mathématicien lillois, spécialiste international en mécanique des fluides et directeur de l'Institut de mécanique des fluides de Lille (IMFL) depuis sa création en 1929. En se familiarisant avec ce domaine et avec les questions expérimentales grâce à ses travaux de balistique pendant sa mobilisation ...

Soutenue le 24 octobre Diplôme : Dr. d'Universite ; During this study, a bibliographic review on hydrogen production has been performed together with applied mathematics considerations such as modelling, estimation and control. This has been combined with a survey paper on biogas production which showed that nowadays, biogas is under produced by 25 to 40%. Optimisation of industrial biogas processes has thus a great potential and should provide a better economy of these plants, independent of political decisions. Moreover, a techno-economical comparison demonstrated the benefits of a 2- step process (H2+CH4) compared to the classical 1-step methane production. From experimental data obtained using industrial molasses, a pseudo-stoichiometric matrix of hydrogen production has been determined based on a Principal Component Analysis (PCA) of the metabolites fluxes. Coefficients of the matrix were identified from a non linear optimisation that guaranteed positive reaction rates. This procedure used the eigen vectors of the PCA combined with a sequential quadratic programming algorithm. A dynamic mass balanced model was then proposed based on the stoichiometric matrix and models parameters were identified for pH values around 5.5. Values very close to theoretical ones were obtained and the model was validated using experimental data from our lab scale process and from different data found in the literature. Finally, hydrogen production was optimised using a predictive control law using asymptotic and an input observers. These observers were used to generate the initial conditions and a predictive horizon of 3.5 h. was chosen. Experiments demonstrated that hydrogen production could be almost doubled (360 to 630 ml-H2.h-1) while keeping substrate conversion higher than 95%. ; Au cours de ce travail, une étude bibliographique a été effectuée sur la problématique de la production de l'hydrogène et sur divers aspects de l'Automatique: modélisation, estimation et commande. Elle a été complétée par un article de synthèse ...