Estudiar concepcions-idees d'estudiantes en ciències utilitzant teorias d'argumentació

Durant les últimes dècades, hi ha hagut un gran interès, en l'àrea de la didàctica de les ciències, per la investigació de les idees prèvies els alumnes en ciències. En el nostre treball no es tracta de trobar i identificar aquestes idees, sinó de trobar el sentit comú en què es basen aquestes idees. Ens proposem trobar esquemes de raonament, o argumentativos, espontanis que es troben detràs d'aquestes concepcions científiques d'estudiantes de Magisteri. El nostre marc analítico s'elabora a partir de la Teoria d'argumentació d'Aristòtil i de teorias més contemporànies com la de Perelman, Toulmin i Walton per a tenir un llistat el més ampli possible dels esquemes d'argumentació del nostre sentit comú actual

An explicitly solvable model of the spontaneous PT-symmetry breaking

We contemplate the pair of the purely imaginary delta-function potentials on a finite interval with Dirichlet boundary conditions. The two parameter model exhibits nicely the expected quantitative features of the unavoided level crossing and of a "phase-transition" complexification of the energies. Combining analytic and numerical techniques we investigate strength- and position-dependence of its spectrum.Comment: presented in the int. conference "Pseudo-Hermitian Hamiltonians in Quantum Physics III" (Instanbul, Koc University, June 20 - 22, 2005). accepted in Czechoslovak J. Phy

HBM, present and future of HPC based on FPGAs

In the past decades, advances in the speed of commodity CPUs have far out-paced advances in memory latency. Mainmemory access is therefore increasingly a performance bottleneck for many computer applications, including HPC embedded systems. This translates into unprecedented memory performance requirements in critical systems that the commonly used DRAM memories struggle to provide. High-Bandwidth Memory (HBM) can satisfy these requirements offering high bandwidth, low power and highintegration capacity features. However, it remains unclear whether the predictability and isolation properties of HBM are compatible with the requirements of critical embedded systems. In our research, a deep characterization of the HBM for its use in MEEP applications is performed

Chapter 3 - Mobility on demand (MOD) and mobility as a service (MaaS): early understanding of shared mobility impacts and public transit partnerships

Technology is changing the way we move and reshaping cities and society. Shared and on-demand mobility represent notable transportation shifts in the 21st century. In recent years, mobility on demand (MOD)—where consumers access mobility, goods, and services on-demand by dispatching shared modes, courier services, public transport, and other innovative strategies—has grown rapidly due to technological advancements; changing consumer preferences; and a range of economic, environmental, and social factors. New attitudes toward sharing, MOD, and mobility as a service (MaaS) are changing traveler behavior and creating new opportunities and challenges for public transportation. This chapter discusses similarities and differences between the evolving concepts of MaaS and MOD. Next, it characterizes the range of existing public transit and MOD service models and enabling partnerships. The chapter also explores emerging trends impacting public transportation. While vehicle automation could result in greater public transit competition in the future, it could also foster new opportunities for transit enhancements (e.g., microtransit services, first- and last-mile connections, reduced operating costs). The chapter concludes with a discussion of how MOD/MaaS partnerships and automation could enable the public transit industry to reinvent itself, making it more attractive and competitive with private vehicle ownership and use

Two dimensional dynamical systems which admit Lie and Noether symmetries

We prove two theorems which relate the Lie point symmetries and the Noether symmetries of a dynamical system moving in a Riemannian space with the special projective group and the homothetic group of the space respectively. The theorems are applied to classify the two dimensional Newtonian dynamical systems, which admit a Lie point/Noether symmetry. Two cases are considered, the non-conservative and the conservative forces. The use of the results is demonstrated for the Kepler - Ermakov system, which in general is non-conservative and for potentials similar to the H\`enon Heiles potential. Finally it is shown that in a FRW background with no matter present, the only scalar cosmological model which is integrable is the one for which 3-space is flat and the potential function of the scalar field is exponential. It is important to note that in all applications the generators of the symmetry vectors are found by reading the appropriate entry in the relevant tables.Comment: 25 pages, 17 table

Rooted in the Soil: The Social Experiences of Black Graduate Students at a Southern Research University

The experiences of Black graduate alumni, 1962-2003, at a major Southern Research University were examined in a comprehensive survey. The areas explored were: relationships with faculty, students, and the institution

Estudiar concepcions-idees d'estudiantes en ciències utilitzant teorias d'argumentació

Durant les últimes dècades, hi ha hagut un gran interès, en l'àrea de la didàctica de les ciències, per la investigació de les idees prèvies els alumnes en ciències. En el nostre treball no es tracta de trobar i identificar aquestes idees, sinó de trobar el sentit comú en què es basen aquestes idees. Ens proposem trobar esquemes de raonament, o argumentativos, espontanis que es troben detràs d'aquestes concepcions científiques d'estudiantes de Magisteri. El nostre marc analítico s'elabora a partir de la Teoria d'argumentació d'Aristòtil i de teorias més contemporànies com la de Perelman, Toulmin i Walton per a tenir un llistat el més ampli possible dels esquemes d'argumentació del nostre sentit comú actual

Influencia de la vía de abordaje y de posición de la cúpula acetabular en la luxación de la artroplastia total de cadera: estudio caso-control

Tanto la vía de acceso quirúrgica como la posición de los componentes se han relacionado con la presencia de una luxación en las artroplastias primarias de cadera. Hemos estudiado la presencia de esta complicación en una serie de 758 artroplastias no cementadas modelo Bihapro. Encontramos 21 luxaciones. Por otro lado se seleccionó de forma aleatoria un grupo de control de 42 pacientes que no habían presentado luxación. Se diseñó un estudio de casos y controles que englobaba por tanto a 63 pacientes que tenían implantada una artroplastia de este modelo. En el grupo de casos observamos que el porcentaje de luxación fue sensiblemente mayor en el sexo masculino con un 66,7%, en comparación con el sexo femenino que fue de un 42,8% aunque esta diferencia no fue estadísticamente significativa. No se observaron diferencias en la frecuencia de luxaciones en relación con la vía anterior o lateral, pero sin embargo en la vía posterior la luxación se produjo en un solo caso (4,8% de todas las luxaciones) con una incidencia claramente menor que en los abordajes anterior y lateral, siendo esta diferencia estadísticamente significativa (p=0,005). También observamos diferencias estadísticamente significativas en cuanto a un mayor porcentaje de luxaciones cuando la inclinación del componente acetabular era mayor de 50º (76,2%), o cuando la anteversión del cotilo era mayor o igual a 20º (54,4%). La vía de abordaje posterior con reconstrucción capsular y muscular presenta un menor porcentaje de luxación después de una artroplastia primaria en comparación con la anterior o lateral. Una inclinación mayor de 50º o una anteversión mayor de 20º favorecen la presencia de una luxación.The surgical approach and the cup position have been related with the dislocations of total hip arthroplasty. We have studied the presence of this complication in 758 Bihapro™ cementless arthroplasties. We got a case group of 21 dislocations; then we selected a control group of 42 patients without luxation to design a case-control study. The case group had a higher rate of dislocation in males (66.7 % versus 42.8 % in females) although this difference was not statistically significant. We didn’t observe any difference in the frequency of luxations relating to the anterior or lateral surgical approach, however in the posterior approach the dislocation appeared only in one case (4.8 % of the all dislocations) with statistically differences (p=0.005). We also observed statistically significant differences of luxations when the acetabular cup inclination was higher than 50º (76.2 %), or when the cup anteversion was equal or higher than 20º (52.4 %). The posterior surgical approach with capsular and muscular suture presented a lower rate of dislocation after a primary arthroplasty compared with the anterior or lateral approachs. An inclination bigger than 50º or an anteversion bigger than 20º seems to be a risk factor of luxation