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The choke flutter is a fluid-structure interaction that can lead to the failure of fan or compressor blade in turbojet engines. In ultra high bypass ratio (UHBR) fans, the choke flutter appears at part-speed regimes and at low or negative incidence when a strong shock-wave chokes the blade to blade channel. The purpose of this study is to locate the main excitation sources and improving the understanding of the different work exchange mechanisms. This work contributes to avoiding deficient and dangerous fan design.

In this paper, an UHBR fan is analyzed using a time-linearized Reynolds-averaged Navier–Stokes equation solver to investigate the choke flutter. The steady-state and the imposed vibration (inter blade phase angle, reduced frequency and mode shape) are selected to be in choke flutter situation. Superposition principle induced by the linearization allow to decompose the blade in numerous small subsections to track the contribution of each local vibration to the global damping. All simulations have been performed on a two-dimensional blade to blade extraction.

Result analysis points to a restricted number of excitation sources at the trailing edge which induce a large part of the work exchange in a limited region of the airfoil. Main phenomena suspected are the shock-wave motion and the shock-wave/boundary layer interaction.

An original excitation source tracking methodology allowed by the linearized calculation is addressed and applied to a UHBR fan test case.

LES bibliothèques françaises se trouvent encore trop sous l'influence des conditions matérielles où les a laissées la guerre, pour qu'on puisse passer sous silence les difficultés qu'elles ont éprouvées. Un certain nombre d'entre elles ont vu leurs collections partiellement ou mme totalement détruites; c'est le cas de la bibliothèque universitaire de Nancy, des bibliothèques municipales de Lille, d'Arras, de Mézières, de Noyon, de Reims, de Réthel, de Saint‐Quentin, de Verdun, pour ne citer que les plus importantes. Il a fallu construire de nouveaux édifices et remplacer les volumes; c'est un travail de longue haleine, mais il commence à toucher à son terme. A Reims, la bibliothèque est rebtie, sur ses rayons ont pris place 66,000 vol. au lieu des 125,000 qu'elle possédait auparavant; de mme à Arras 1,200 manuscrits sur 2,500, 21,000 vol. sur 49,000 ont été sauvés; la bibliothèque de Réthel se relève de ses ruines, celle de Verdun est achevée.

Introduction How old is concrete? 150 years, 2,000 years or 9,000 years? Since the invention of Portland cement by Aspdin in the early 19th century, concrete has become the most widely used construction material in the world. Yet, concrete durability can pose severe constraints on the concrete engineer and designer. In the search for materials which are more cost‐effective or more efficient, cement replacement materials such as natural pozzolans, calcined clays, shale and soils, slags, rice husk ash or pulverised fuel ash are attracting much interest. Are these cheap replacement materials not compromising on quality and long‐term durability? A first optimistic answer is given in this paper which will be especially useful for practising civil and structural engineers, materials technologists, engineers and designers.

The aim is to identify Henri Fayol's motivations as an accomplished business manager to publish his management theory at the age of 75.

The authors retrace Henri Fayol's private life using primary sources from various French public archives including civil registry records, military and diplomatic archives, schooling records, publications from learned associations and inheritance declarations. They then use a psychological theory, namely equity theory, to interpret this new information about Fayol's private life and construct an explanation of his efforts to theorise his management experience.

Henri Fayol's schooling and his father's military career respectively influenced his perception of mathematics teaching in management training and the functioning of the army. His motivation to found a science of management was not financial but instead most probably a response to the obstacles his father encountered during his career.

It is rarely known what motivates a manager to collaborate with specialists in management science. This research into Henri Fayol's motivations can be replicated for other managers.

The paper dentifies one major practical implication for managers who wish to contribute to management theory as Fayol did. Before they begin such an undertaking, it is important for them to reflect upon their motivations. Their motivations as managers, based on financial and business success are insufficient. Deeper motivations are needed, that are anchored in their own personal history to drive the considerable intellectual investment that is necessary for them to be successful contributors.

The results encourage managers to contribute to building and improving management science. They can theorize their experiences in dealing with the management of contemporary issues such as sustainable development and social responsibility. They must do so as Fayol did: using scientific method and strongly motivated by personal beliefs.

The research question is original: “What motivated Fayol to build his management doctrine?”. Scholars rarely ask why individuals decide to build and organize knowledge. This question is relevant for managers today as they too can bring original contributions to management thought. The paper reports previously unpublished details about Fayol's life to answer the research question, and in doing so completes and corrects the works of Sasaki Tsuneo and Henri Verney.

1. En guise d’introduction.‐ 2. Droit du tra vail, droit social et (des)ordre international.‐ 3. Droit du tra vail, droit social, légalité et droits sociaux.‐ 4. Droit du travail, droit social, légalité et correction des inégalités.‐ 5. Quelques mots á propos du rôle du Droit dutravail.‐ 6. Réflexions (supplémentaires) sur le droit du tra vail: les domaines possibles de spéculation théorique et de re cher che appliquée.‐ 7. En matière des orientations générales du droit du travail á l’époque contemporaine. ‐ 8. Le défi de la mondialisation.‐ 9. èour un modèle économique et so cial européen.‐ 10. A propos de Constitution européenne et ..... alentours.‐ 11. Le traitement juridique de la ques tion économique et sociale en Eu rope.‐ 12. Le mythe de la li bre concurrence.‐ 13. Quelques conclusions, pas conclusives.‐