3,241 research outputs found

    Mathematics Teachers’ Working with Cooperative Learning

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    Teaching styles vary greatly amongst educators. One being extensively researched and highly discussed is the method of cooperative learning. Although many studies have shown the benefits of incorporating cooperative learning into classrooms, it has not been a widely used method of teaching in high school mathematics classrooms. This study explores some of the efforts that teachers, who utilize cooperative learning in their classrooms, make to implement cooperative learning lessons successfully. Furthermore, this study also explores the challenges these teachers have encountered when using cooperative learning. Data was collected qualitatively by interviews and surveys from six in-service high school teachers who planned and incorporated cooperative learning lessons in their classes. The data collected from interviews and surveys revealed that although many teachers potentially saw the benefits of the social interaction aspect of cooperative learning, they would not use this method of teaching regularly due to the difficulties of implementing an effective cooperative learning lesson. These difficulties included the amount of time it took to plan a cooperative learning lesson, not being trained on how to implement a cooperative learning lesson, and the students not knowing how to properly work together in a cooperative learning setting. It is beneficial to learn the challenges high school mathematics teachers have encountered in incorporating cooperative learning lessons so that those issues (challenges) can be addressed and be used to improve future cooperative learning lessons to make them as effective as possible. Furthermore, analyzing the various efforts teachers used to create an effective cooperative learning lesson and the challenges they encountered, indicates teachers would benefit from trainings on how to properly structure and implement cooperative learning lessons in their classrooms. With proper training and the willingness of teachers to apply cooperative learning in their classrooms, high school mathematics teachers can utilize effective cooperative learning strategies

    Methodological Flaws in Cognitive Animat Research

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    In the field of convergence between research in autonomous machine construction and biological systems understanding it is usually argued that building robots for research on auton- omy by replicating extant animals is a valuable strategy for engineering autonomous intelligent systems. In this paper we will address the very issue of animat construction, the ratio- nale behind this, their current implementations and the value they are producing. It will be shown that current activity, as it is done today, is deeply flawed and useless as research in the science and engineering of autonomy

    Coherent absorption and enhanced photoluminescence in thin layers of nanorods

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    We demonstrate a large light absorptance (80%) in a nanometric layer of quantum dots in rods (QRs) with a thickness of 23 nm. This behavior is explained in terms of the coherent absorption by interference of the light incident at a certain angle onto the very thin QR layer. We exploit this coherent light absorption to enhance the photoluminescent emission from the QRs. Up to a seven- and fivefold enhancement of the photoluminescence is observed for p- and s-polarized incident light, respectively.Comment: Physical Review B 201

    Interaction and coherence of a plasmon-exciton polariton condensate

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    Polaritons are quasiparticles arising from the strong coupling of electromagnetic waves in cavities and dipolar oscillations in a material medium. In this framework, localized surface plasmon in metallic nanoparticles defining optical nanocavities have attracted increasing interests in the last decade. This interest results from their sub-diffraction mode volume, which offers access to extremely high photonic densities by exploiting strong scattering cross-sections. However, high absorption losses in metals have hindered the observation of collective coherent phenomena, such as condensation. In this work we demonstrate the formation of a non-equilibrium room temperature plasmon-exciton-polariton condensate with a long range spatial coherence, extending a hundred of microns, well over the excitation area, by coupling Frenkel excitons in organic molecules to a multipolar mode in a lattice of plasmonic nanoparticles. Time-resolved experiments evidence the picosecond dynamics of the condensate and a sizeable blueshift, thus measuring for the first time the effect of polariton interactions in plasmonic cavities. Our results pave the way to the observation of room temperature superfluidity and novel nonlinear phenomena in plasmonic systems, challenging the common belief that absorption losses in metals prevent the realization of macroscopic quantum states.Comment: 23 pages, 5 figures, SI 7 pages, 5 figure
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