Search results for "Tarea"
showing 10 items of 182 documents
The Transverse Crack Tension test revisited
2016
Several problems arise when measuring the mode II interlaminar fracture toughness using a Transverse Crack Tension specimen; in particular, the fracture toughness depends on the geometry of the specimen and cannot be considered a material parameter. A preliminary experimental campaign was conducted on TCTs of different sizes but no fracture toughness was measured because the TCTs failed in an unacceptable way, invalidating the tests. A comprehensive numerical and experimental investigation is conducted to identify the main causes of this behaviour and a modification of the geometry of the specimen is proposed. It is believed that the obtained results represent a significant contribution in …
Evaluating the citywide Edinburgh 20mph speed limit intervention effects on traffic speed and volume: A pre-post observational evaluation.
2021
Objectives Traffic speed is important to public health as it is a major contributory factor to collision risk and casualty severity. 20mph (32km/h) speed limit interventions are an increasingly common approach to address this transport and health challenge, but a more developed evidence base is needed to understand their effects. This study describes the changes in traffic speed and traffic volume in the City of Edinburgh, pre- and 12 months post-implementation of phased city-wide 20mph speed limits from 2016–2018. Methods The City of Edinburgh Council collected speed and volume data across one full week (24 hours a day) pre- and post-20mph speed limits for 66 streets. The pre- and post-sp…
Análisis de los modelos matemáticos producidos durante la resolución de problemas de Fermi
2017
[EN] In this paper, we present an analysis of written productions of 16 year-old students while solving Estimation Problems involving Big Numbers (EPiBN). This kind of problems is a particular type of Fermi problems and allows us to introduce modelling processes in Secondary school classrooms. Our analysis supports on the characterization of mathematical models developed by students based on the model definition of Lesh and Harel. The results show that, through the analysis of EPiBN resolutions, differentiating aspects can be distinguished between the models produced by students without modelling experience of those produced by students with prior experience, especially in the concepts and …
Avances de investigación en educación matemática
2020
El fomento de la flexibilidad y adaptabilidad en resolución de problemas matemáticos favorece el desarrollo de la competencia matemática. En este estudio se describe y justifica el diseño de una secuencia de tareas de modelización que permite analizar la flexibilidad inter-tarea en los estudiantes. El objetivo central del estudio es analizar si los estudiantes son capaces de adaptar sus planes de resolución según aspectos relativos al contexto de la tarea, cambiando de estrategia de una tarea a otra, si estos aspectos varían. En el estudio han participado 110 estudiantes del grado de Maestro/a en Educación Primaria; los resultados permiten conocer en qué medida son flexibles los estudiantes…
Management of Cultural Landscapes: What Does this Mean in the Former Soviet Union? A Case Study from Latvia
2009
Concern about changing cultural landscapes has increased recently, with the advent of the European Landscape Convention placing signatory countries in a position of having to develop action for protecting and managing cultural landscapes. In countries of the former Soviet Union the landscape underwent many changes as a result of agricultural collectivisation and its aftermath. This situation has been analysed for six sample rural municipalities (pagasts) in Latvia, one of the three former Soviet countries to join the European Union (EU), using maps from the period 1901 to 1927 (to represent the ‘traditional landscape’) and 1997 orthophotographs updated to 2000 (to represent the ‘post-Soviet…
The role of perspective on students’ use of multiple documents to solve an openended Task
2013
AbstractMcCrudden & Schraw (2007) show how students’ interaction with a text is mediated by the instructions they are presented with. Specifically, perspective instructions prompt readers to use background knowledge to evaluate text from an assigned point of view. Research on perspective in single texts has demonstrated that readers confer relevance on text segments that are consistent with the assigned perspective (Pichert & Anderson, 1977). This work has tested the effects of perspective when reading conflicting information from multiple documents to perform an open-ended task, as well as has studied if the trustworthiness of a source exerts any influence on students’ decision to use info…
Cold-Atom-Induced Control of an Optomechanical Device
2010
We consider a cavity with a vibrating end mirror and coupled to a Bose-Einstein condensate. The cavity field mediates the interplay between mirror and collective oscillations of the atomic density. We study the implications of this dynamics and the possibility of an indirect diagnostic. Our predictions can be observed in a realistic setup that is central to the current quest for mesoscopic quantumness.
Internationalization pathways of family SMEs:Psychic distance as a focal point
2010
Purpose: The purpose of this paper is to investigate how psychic distance affects the internationalization process, foreign market entry (FME), and entry mode choice of Finnish small and medium-sized family enterprises (family SMEs) operating in France. Design/methodology/approach: The paper reports findings from an in-depth case study covering four Finnish manufacturing family SMEs operating in the French market. The data were analyzed using the Uppsala model and distance creating and distance-bridging factors encountered in the FME to France. Findings: The findings reveal that the family SMEs mainly followed a sequential process and favored indirect entry modes before entering the French …
La Comisión Europea
2001
Se trata de una carta al director de Jonathan Faull reaccionando al artículo "Suicidio programado", publicado por Vidal-Beneyto en "El País" el 9 de mayo de 2001.
Enhancerless Cytomegalovirus Is Capable of Establishing a Low-Level Maintenance Infection in Severely Immunodeficient Host Tissues but Fails in Expon…
2010
ABSTRACT Major immediate-early transcriptional enhancers are genetic control elements that act, through docking with host transcription factors, as a decisive regulatory unit for efficient initiation of the productive virus cycle. Animal models are required for studying the function of enhancers paradigmatically in host organs. Here, we have sought to quantitatively assess the establishment, maintenance, and level of in vivo growth of enhancerless mutants of murine cytomegalovirus in comparison with those of an enhancer-bearing counterpart in models of the immunocompromised or immunologically immature host. Evidence is presented showing that enhancerless viruses are capable of forming restr…