197,395 research outputs found
Allouche-Benayoun, J., Pariat, M. (1993) - La fonction formateur. Analyse identitaire d'un groupe professionnel.
Hédoux Jacques. Allouche-Benayoun, J., Pariat, M. (1993) - La fonction formateur. Analyse identitaire d'un groupe professionnel.. In: Recherche & Formation, N°16, 1994. Les professions de l'éducation : recherches et pratiques en formation. pp. 145-146
Internet - the Sublimation of the Global Body, Global Perspectives,China Practice - First International Collaborative Forum on Internet Governance, Institute ofJournalism and Communication, Chinese Academy of Social Science, Beijing Normal University, JingshiInternational Academy Exchange Center, Beijing, 22-23 Oct. 2016
Benayoun, M., keynote speaker, Internet - the Sublimation of the Global Body, Global Perspectives,China Practice - First International Collaborative Forum on Internet Governance, Institute ofJournalism and Communication, Chinese Academy of Social Science, Beijing Normal University, JingshiInternational Academy Exchange Center, Beijing, 22-23 Oct. 201
EVIDENCE FOR HIGHER TWIST MECHANISMS IN PROMPT rho0 MESON PRODUCTION AT P(T) > 2-GeV/c IN 300-GeV/c pi- N INTERACTIONS.
Texturation de surface de pièces polymères injectées à partir de la structuration submicronique du moule
Depuis plusieurs années, on cherche à fonctionnaliser les surfaces de tout type de matériaux que ce soit pour le biomédical, la recherche ou l’industrie des transports afin de conférer de nouvelles propriétés (antibuée, réduction du frottement, dégivrage…). Parmi les techniques de traitement de surface, l’ablation au moyen d’un laser à impulsions ultra-brèves offre la possibilité d’élaborer des textures submicroniques, qui jouent un rôle essentiel dans leur comportement fonctionnel. Toutefois, dans le cas de production en grande série, il est préférable pour des questions de coûts, de reproduire ces textures avec une technique de reproduction d’empreinte.Ce travail porte sur l’étude des différents facteurs impliqués dans la réplication par injection plastique de topographies submicroniques. Il s’agit de comprendre l’influence des paramètres du procédé d’injection, des propriétés du polymère injecté et de la chimie de surface du moule (avec ou sans revêtement) sur la qualité de la pièce injectée.Une première étude a été réalisée sur deux polypropylènes de viscosité différente sous faible taux de cisaillement (grade MFR). Une première étape a consisté à développer une nouvelle méthodologie pour quantifier la qualité de réplication de structures submicroniques périodiques et aléatoires entre la pièce injectée et le moule, avant de mettre en œuvre une série d’injections. Pour des paramètres d’injection identiques, on observe que la qualité de réplication des motifs sur les pièces injectées est différente. Une étude approfondie des caractéristiques structurales et rhéologiques des polymères a été réalisée. Cette différence de réplication n’est pas dues à leur viscosité dans les conditions d’injection en dépit de grades MFR très différents mais de leur mode de relaxation de contraintes pendant la phase de refroidissement [1]. Une deuxième étude s’est concentrée sur l’influence de la chimie de surface des moules lors du remplissage des cavités dans le procédé d’injection. Nous avons principalement étudié le phénomène d’adhésion d’un polymère fondu sur différents substrats revêtus de dépôt à base de nitrures de chrome ou de titane ainsi qu’un dépôt de DLC (Diamond Like Carbon). A partir d’essais de mouillage en température et de mesures d’énergie de surface des polymères fondus, nous avons déterminé le travail d’adhésion du polymères sur les moules revêtus (ou non) aux températures d’injection [2]. A partir de ces résultats nous avons tenté de mener un travail de synthèse en développant une approche statistique basée sur l’analyse de plans d’expériences afin de quantifier l’influence de différents facteurs tant procédés (vitesses d’injection, vide dans l’empreinte, température moule, …) que matériaux (différents polymères, différents revêtements sur le moule). Nous avons montré que les échanges thermiques à l’interface moule-polymère avaient un rôle prépondérant dans la qualité de réplication. Ces échanges dépendent notamment de la nature des revêtements qui conditionne la formation de la gaine solide lors de la microinjection [3].[1] J. Vera, A.-C. Brulez, E. Contraires, M. Larochette, S. Valette, S. Benayoun, Influence of the polypropylene structure on the replication of nanostructures by injection molding, J. Micromech. Microeng. 25 (2015) 115027. doi:10.1088/0960-1317/25/11/115027.[2] J. Vera, E. Contraires, A.-C. Brulez, M. Larochette, S. Valette, S. Benayoun, Wetting of polymer melts on coated and uncoated steel surfaces, Applied Surface Science. 410 (2017) 87–98. doi:10.1016/j.apsusc.2017.02.067.[3] J. Vera, A.-C. Brulez, E. Contraires, M. Larochette, N. Trannoy-Orban, M. Pignon, C. Mauclair, S. Valette, S. Benayoun, Factors influencing micro-injection quality, Journal of Micromechanics and Microengineering. (soumis en juin 2017).Over the past decades, industrial and academic research groups have been trying to functionalize surfaces, i.e. provide new properties to surfaces, in order to obtain specific functions such as friction reduction, anti-fog or de-icing properties. Among the various existing surface treatment techniques, laser ablation using an ultra-short pulse laser gives the opportunity to generate submicronic textures, which play an essential role in their functional behavior. However, in the case of mass production of textured surfaces, it is preferable to reproduce these textures with a fingerprinting technique for reasons of cost-effectiveness.This work focuses on the study of the various factors involved in the replication of submicronic topographies by plastic injection. Understanding the influence of the parameters of the injection process, the properties of the injected polymer and the surface chemistry of the mold (with or without coating) is key to controlling the quality of the injected part.A first study was carried out on two polypropylenes of different viscosities under low shear rate (MFR grade). A first step was to develop a methodology enabling to quantify the quality of replication of periodic and random submicron structures between the injected part and the mold. For identical injection parameters, it was observed that the quality of replication of the patterns on the injected parts was different when viscosity changed. A study of the structural and rheological characteristics of the polymers was carried out. This difference in replication was not due to their viscosity under the injection conditions in spite of very different MFR grades but to their mode of stress relaxation during the cooling phase [1]. A second study focused on the influence of the surface chemistry of molds when filling the cavities in the injection process. We mainly studied the phenomenon of adhesion of a molten polymer on different chromium nitride, titanium-based and DLC films deposited on mold substrates. From the temperature wetting tests and the surface energy measurements of the molten polymers, we determined the work of adhesion between the polymers and the coated or non-coated molds at injection temperatures [2]. On the basis of these results, we performed a synthesis work by developing a statistical approach based on the analysis of experimental plans in order to quantify the influence of various factors, both process (injection rates, Impression, mold temperature, etc.) and material (different polymers, different coatings on the mold) related. We showed that thermal exchanges at the mold-polymer interface had a dominant role in the quality of replication. In particular, these exchanges depend on the nature of the coatings and regulates the formation of the solid sheath during microinjection [3].[1] J. Vera, A.-C. Brulez, E. Contraires, M. Larochette, S. Valette, S. Benayoun, Influence of the polypropylene structure on the replication of nanostructures by injection molding, J. Micromech. Microeng. 25 (2015) 115027. doi:10.1088/0960-1317/25/11/115027.[2] J. Vera, E. Contraires, A.-C. Brulez, M. Larochette, S. Valette, S. Benayoun, Wetting of polymer melts on coated and uncoated steel surfaces, Applied Surface Science. 410 (2017) 87–98. doi:10.1016/j.apsusc.2017.02.067.[3] J. Vera, A.-C. Brulez, E. Contraires, M. Larochette, N. Trannoy-Orban, M. Pignon, C. Mauclair, S. Valette, S. Benayoun, Factors influencing micro-injection quality, Journal of Micromechanics and Microengineering. (soumis en juin 2017)
Die Scheinheiligkeit des Kleinbürgers – Zur Funktion von Sprichwörtern in Ödön von Horváths Geschichten aus dem Wiener Wald (1931)
Preußer U. Die Scheinheiligkeit des Kleinbürgers – Zur Funktion von Sprichwörtern in Ödön von Horváths Geschichten aus dem Wiener Wald (1931). In: Benayoun J-M, Kübler N, Zouogbo J-P, eds. Parémiologie. Proverbes et formes voisines. Vol 3. Saint Gemme: Presses Universitaires de Sainte Gemmes; 2013: 143-158
Dr. Duane M. Jackson, Morehouse College, July 2011
This video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
Hosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
Following an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
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