L'uranium et les armes a l'uranium appauvri

Selon la presse, dans la guerre des Balkans et bien plus massivement dans la guerre du Golfe, des obus anti- chars ont ete utilises, avec des "charges d'uranium appauvri". La presse a decrit deux types de ces "obus- crayons", l'un de diametre 30 mm et 300 mm de long, avec une charge de 300 g d'uranium et tire par des avions, l'autre de 120 mm de diametre avec une charge de 1 a 5 Kg d'uranium, tire par des chars et donc peu ou pas utilise au Kosovo. Les commentaires ont ete varies. On a parle d'armes atomiques, on a dit que c'etait completement inoffensif ou au contraire tres dangereux. Les elements d'information qui suivent tentent d'eclairer le probleme, car on va montrer que probleme il y a, avec des donnees incontournables. Mais faute d'une enquete approfondie et faute d'informations precises, on conclura aussi avec des questions. Il a semble utile egalement de decrire quelques-unes des realites de la radioactivite et de parler du role particulier de l'uranium 238 pour notre planete

ETUDE DE LA STRUCTURE DES NOYAUX PAR REACTIONS DE TRANSFERT : IONS LEGERS ET IONS LOURDS

On examine quels sont les éléments de la structure nucléaire accessibles par réaction de transfert. On insiste sur lien entre la sélectivité de la réaction, son mécanisme et la structure atteinte. Les différences entré projectiles lourds et légers sont examinées en développant particulièrement l'analyse semi-classique du transfert qui met en évidence l'importance de la dynamique de la réaction et celle de l'adaptation de moment angulaire. Il apparaît que les transferts à énergie par nucléon élevée (E/A ≳ 5 MeV au-dessus de la barrière) ont été peu explorés en ions lourds alors que la présence, dans ce cas, d'un moment orbital interne devrait leur donner une spécificité dans les structures atteintes. Quelques exemples récents d'utilisation des réactions de transfert sont ensuite passes en revue. On conclut en décrivant un progrès expérimental devant permettre l'amélioration de la résolution en énergie dans les transferts en ions lourds

L'argument Einstein Podolsky Rosen (EPR) :Paradoxe, Alternative, Démonstration.

publication interne IPNO DR 02-20 (2002-2003) en liaison avec un séminaire : "Le chat de Schrödinger : un agent retourné." IPNO juin 2002 - publication interne IPNO DR 02-20 (2002-2003) en liaison avec un séminaire : "Le chat de Schrödinger : un agent retourné." IPNO juin 2002The EPR (Einstein, Podolsky, Rosen) argument and the Schrödinger cat paradoxare revisited in relation with modern quantum optics and atomic physics andwith the concept of decoherence. It is shown that the questions raised fiftyyears ago are still at the heart of our understanding of quantum physicstoday

Les inégalités de Bell et l'article Einstein, Podolsky, Rosen, une relecture

The relationship between the Bell article in 1964 and its well known inequalities with the Einstein Podolsky Rosen article in 1935 is revisited. Einstein views on quantum mechanics as stated in many circumstances up to his death in 1955 are recalled. The role of David Bohm is shown to be essential to understand the link between Bell and Einstein's views. This link appears not to be as usually recounted

Adaptive low-rank approximation and denoised Monte-Carlo approach for high-dimensional Lindblad equations

We present a twofold contribution to the numerical simulation of Lindblad equations. First, an adaptive numerical approach to approximate Lindblad equations using low-rank dynamics is described: a deterministic low-rank approximation of the density operator is computed, and its rank is adjusted dynamically, using an on-the-fly estimator of the error committed when reducing the dimension. On the other hand, when the intrinsic dimension of the Lindblad equation is too high to allow for such a deterministic approximation, we combine classical ensemble averages of quantum Monte Carlo trajectories and a denoising technique. Specifically, a variance reduction method based upon the consideration of a low-rank dynamics as a control variate is developed. Numerical tests for quantum collapse and revivals show the efficiency of each approach, along with the complementarity of the two approaches.Comment: 5 pages, 3 figures, Submitte

Exploring Emergency Communication Experiences in Response to the 2010 Haiti Earthquake: Lessons Learned from International Donors and Local Government Agencies

Background: In almost every disaster situation, the use of standardized communication procedures among humanitarian relief agencies has been identified as one of the efficient practices to minimize the mismanagement of resources and thus to maximize the response effort among actors to reduce the incidence impact on the public and to increase their resilience capabilities. Agencies have access to several guidelines to follow during domestic disasters, but there have been very few manuals developed to guide relief organizations on best practices during international large and complex natural disasters such as the 2010 Haiti earthquake. Haiti has experienced over its history several years of natural disasters, political, social-economic instability and recently has been devastated by one of the worst earthquakes that humanity has ever known. Methods and Findings After the 7.1 earthquakes on January 12, 2010, it was reported that over 10,000 relief agencies, nonprofit organizations had deployed their staff for a short or a long term period to support the response and recovery effort. In order to explore the communication experiences and patterns of local and international agencies, a qualitative research study was administered, consisting of conducting semi-structured phone interviews with seventeen (17) respondents who participated in the complex humanitarian response in Haiti six years ago, using an eight question interview between February 4th and March 6th, 2016. Data and information captured through the interview process were used to document the communication process systematically, the strengths and limitations, the lessons learned and recommendations provided by the respondents. Snowball sampling was used to identify and recruit participants who have traveled as emergency medical specialists or whose responsibilities helped with the coordination of the response. Interviews were conducted in English or French and Haitian Creole depending on the participant’s linguistic preference and country of citizenship. Interview transcripts, notes and codes were analyzed using key themes proposed as a framework for the study. Conclusion: Emergency response should not add more burden and responsibilities to government officials’ countries significantly affected by natural disasters and should not cause distress to the affected communities. Rapid response is thus needed but should be efficiently coordinated to avoid wasted supplies, untrained staff and an influx of inexperienced international agencies in a complex and resource limited environment. The absence of a national response plan, the lack leadership and guidance from the Haitian government have been perceived as a sign of weakness by almost all local and international relief agencies and the negative aftermath of the disaster has been exacerbated by the thousands of small organizations that came looking for visibility and ultimately undermined the quality and timeliness of the response. Key Words: Natural Disaster, Haiti, Earthquake, Communication,Relief Agencie

Le profil professionnel des diplômés en éducation physique de l’Université de Moncton : 1968-2001

Cette étude visait à connaître le profil de carrière, le niveau de satisfaction envers la formation universitaire reçue ainsi que les activités de perfectionnement professionnel des détenteurs d’un baccalauréat en éducation physique décerné par l’Université de Moncton depuis une trentaine d’années (1968-2001). L’échantillon comprenait 293 diplômés et l’instrument de mesure consistait en une soixantaine de questions. Pour les sujets interrogés, la recherche du premier emploi s’est particulièrement bien déroulée. Un peu plus de la moitié des diplômés enseignent toujours l’éducation physique. Le niveau de satisfaction face aux études et au travail est élevé. Cependant, la plupart des répondants estiment comme peu probable l’obtention d’une promotion.The objective of this research was to identify the career profile, the level of satisfaction with the university education received, as well as the professional development of holders of a bachelor’s degree in physical education, conferred by the Université de Moncton over thirty years (1968-2001). The sample included 293 graduates, whose responses to approximately 60 questions were used as measurement. For those subjects interrogated, the authors found that the first job search went particularly well. A little over half of the graduates are still teaching physical education. The level of satisfaction relative to studies and work is high, however the possibility of an eventual promotion is highly unlikely.El objetivo de este estudio era conocer el perfil de carrera, el nivel de satisfacción hacia la formación universitaria cursada así como las actividades de capacitación profesional de los titulados de una licenciatura en educación física, concedida por la Universidad de Moncton desde hace unos treinta años (1968-2001). La muestra incluía 293 titulados y el instrumento de medición constaba de alrededor de sesenta preguntas. Resultó que para los encuestados, la búsqueda del primer empleo se pasó particularmente bien. Un poco más de la mitad de los titulados siguen enseñando la educación física. Asimismo, el nivel de satisfacción hacia los estudios y el trabajo es elevado. Sin embargo, la mayoría de los encuestados consideran poco probable lograr a conseguir una promoción