Elipsler, yastıklar ve çanlar. -çoğunlukla- Kuzey Afrika mozaiklerinde yer alan bir familya

The purpose of this article is to characterize a family of geometric mosaic decors which are especially well represented in North Africa (17 pavements on 24) and especially in Tunisia (14 pavements), extending from the second to the fourth century AD. Their common feature is to include three shapes not very frequently found in mosaic, namely the so-called “ellipse”, “cushion” and “bell”. We assume that these “ellipses” are in fact ovals, similar to those used for building the Roman amphitheaters. In the present case they are inscribed in a square and most often carried out following a same process, quite easy to implement (23 pavements). The general pattern of these pavements is set on a grid of bands, the ovals being inscribed in the larger squares of the grid. The other arcs of circles, delineating the cushions and bells, are also carried out in close relationship with this grid. A major element of −relative− variability is the ratio between the widths of the two sorts of bands, thus leaving more space or less for the bells and cushions, and consequently for their respective inner decors.Bu makalenin amacı, İS 2. yüzyıldan 4. yüzyıla kadar uzanan dönemde, özellikle Kuzey Afrika’da (17 döşeme üzerinde 24) ve özellikle Tunus’ta (14 döşemede) iyi temsil edilen bir geometrik mozaik familyasını karakterize etmektir. Bu mozaiklerin ortak özelliği genelde mozaikler üzerinde çok sık rastlanmayan üç şekli, yani “elips”, “yastık” ve “çan”ı içermeleridir. Bu “elipslerin” aslında Roma amfi tiyatrolarının yapımında kullanılanlara benzer ovaller olduğu varsayılmaktadır. Mevcut durumda, bunlar bir kare içinde yer almaktadır, çoğu zaman aynı işlemi izleyerek gerçekleştirilir ve uygulanması oldukça kolaydır (23 döşeme). Bu döşemelerin genel deseni, bir şerit kafesi üzerine kuruludur, ovaller kafesin daha büyük karelerine işlenmiştir. Yastıkları ve çanları betimleyen diğer daire yayları da bu kafesle yakın ilişki içinde yürütülür. Göreceli değişkenliğin önemli bir unsuru, iki tür bandın genişlikleri arasındaki orandır, böylece çanlar ve minderler ve dolayısıyla ilgili iç dekorları için daha fazla veya daha az yer bırakır

Trajectory of a problem: a study in Teacher Training

Problems are frequently used in mathematics to introduce and convey new notions and skills. Hence, teachers transform and adjust those problems to their students\u27 level. The present study focuses on this transformation process on the particular case of a geometric problem posed by two teacher educators in one French Institute for Teacher Training. The whole process is described as a trajectory of the problem through various institutions from training center to secondary school and back. Before presenting the notion of trajectory of the problem, some elements about a general theoretical frame which refers to didactics of mathematics are presented

Les professeurs-stagiaires d’IUFM et les technologies

Cette recherche étudie l’appropriation des TICE et les premiers usages par les stagiaires des IUFM. Cette population est généralement équipée et a bénéficié d’une formation à l’Université et à l’IUFM. L’objectif était de savoir si ces conditions sont suffisantes pour que des usages professionnels se développent ou si des obstacles subsistent. À partir de questionnaires et d’analyse de mémoires, nous mettons en évidence une instrumentation limitée, des pratiques collaboratives faibles et des difficultés à utiliser des logiciels spécifiques aux disciplines.This research studies the learning of ICT (Information and Communications technology) and their first use by teacher trainees. This population is generally equipped and has benefited from a training at university and at the IUFM (teacher training university institute). The goal was to know if these conditions are sufficient to favour the development of professional use or if there remain obstacles. Some questionnaires and an analysis of students’ dissertations have revealed a limited instrumentation, poor collaborative practices and some difficulties in using software specific to subjects.Esta investigación estudia la apropiación de las TICE y los primeros usos por los cursillistas de los IUFM. Esta población es generalmente dotada y se ha beneficiado de una formación en la Universidad y en el IUFM. El objetivo era saber si estas condiciones son suficientes para que se desarrollen usos profesionales o si subsisten obstáculos. A partir de cuestionarios y de análisis de memorias ponemos en evidencia una instrumentación limitada, prácticas colaborativas escasas y dificultades para utilizar logiciales específicos a las disciplinas.Diese Untersuchung analysiert, wie die Referendare der PH sich die I-und K-Technologien aneignen und benutzen. Diese Bevölkerungsgruppe ist im Allgemeinen ausgerüstet und wurde an der Universität und an der PH ausgebildet. Das Ziel bestand darin, zu wissen, ob diese Bedingungen reichten, damit eine berufliche Benutzung sich entwickelt oder ob Hindernisse bestehen.Ausgehend von Fragebogen und Analysen von Examsarbeiten stellen wir eine begrenzte Instrumentation, ein geringes Teamwork und Schwierigkeiten, fachspezifische Softwares zu benutzen, klar

Using spreadsheets to teach probability in French high school

International audienceIncluding a 'frequentist' point of view has resulted in experimentation becoming an important issue in the teaching of probability in high school. Spreadsheets are now widely used, but the status of the results produced and how to use them are not always clear for the students, since two domains are at play in turn: statistics and probability. Through the French example-but this can also be applied to the teaching of probability in other countries − this paper reviews some questions about spreadsheets, namely simulating random experiments and shifting from discrete to continuous distributions

Géométries du compas au collège, avec ou sans règle

International audienc

Representations planes et enseignement de la geometrie de l'espace au lycee. Contribution a l'etude de la relation voir/savoir

SIGLEINIST T 73405 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Représentations planes et enseignement de la géométrie de l'espace au lycée. Contribution à l'étude de la relation voir – savoir.

no summaryDans le secondaire, la figure (le dessin) est une composante essentielle en géométrie de l'espace, mais son statut reste en général flou. Dans cette thèse, l'auteur veut montrer l'intérêt d'un apprentissage explicite de la représentation plane, en perspective parallèle, des objets géométriques, accompagne d'une fréquentation directe d'objets tridimensionnels (maquettes). Un constat: les dessins habituels (ceux des manuels, par exemple) ne sont que rarement rapportés à la projection parallèle, leurs conventions sont implicites et variées; ce sont souvent en fait de véritables stéréotypes. Une enquête : comment les lycéens décodent ces dessins, et comment ils encodent des situations courantes. Il met en évidence la référence implicite à des points de vue habituels (le voir), ainsi qu'une utilisation importante du transfert de propriété (le savoir). Ceci justifie le recours a la perspective parallèle, bien adaptée a l'enseignement secondaire car associant aspect réaliste (voir) et conservation de propriétés (savoir). Une expérimentation: séquence didactique intégrant à l'apprentissage de l'espace celui de ses représentations, à partir d'une étude du phénomène de l'ombre. L'expérience a montre que les élèves y réinvestissent leurs connaissances en géométrie plane, et une évaluation a permis de vérifier une bonne acquisition d'un savoir en géométrie de l'espace, ainsi qu'une capacité a réaliser et a utiliser des dessins corrects et efficaces