Imágenes de Hispanoamérica : Un análisis crítico de material didáctico de ELE

This paper investigates how Latin America and its cultures are represented in textbooks on Spanish as a foreign language. The study aims at investigating how much attention and of what type is dedicated to Latin America in the investigated material, whether the textbooks contribute to giving a varied and nuanced image of the Spanish-American cultures and how this relates to the educational goal of promoting an intercultural competence.A qualitative method of analysis has been applied in order to carry out the analysis of three textbooks for intermediate levels of language studies: Caminando 3, Alegria and De acuerdo.The results of the investigation show that the investigated textbooks mostly present a simplified, ethnocentric, homogenized and sometimes postcolonial image of the Spanish-American cultures. Texts where the culture constitutes the context and not the subject can promote a process of identification and consequently an intercultural competence.The study’s main conclusions show that Spanish-American cultures are underrepresented in the investigated material and that a non-native perspective dominates in the majority of the texts. This combined with the lack of variety and profundity, may have consequences for the promotion of an intercultural competence and for teachers’ work with textbooks and cultural content.

Experimental and computational investigation of the roll forming process

One of the first questions to consider when designing a new roll forming line is the number of forming steps required to produce a profile. The number depends on material properties, the cross-section geometry and tolerance requirements, but the tool designer also wants to minimize the number of forming steps in order to reduce the investment costs for the customer. There are several computer aided engineering systems on the market that can assist the tool designing process. These include more or less simple formulas to predict deformation during forming as well as the number of forming steps. In recent years it has also become possible to use finite element analysis for the design of roll forming processes. The objective of the work presented in this thesis was to answer the following question: How should the roll forming process be designed for complex geometries and/or high strength steels? The work approach included both literature studies as well as experimental and modelling work. The experimental part gave direct insight into the process and was also used to develop and validate models of the process. Starting with simple geometries and standard steels the work progressed to more complex profiles of variable depth and width, made of high strength steels. The results obtained are published in seven papers appended to this thesis. In the first study (see paper 1) a finite element model for investigating the roll forming of a U-profile was built. It was used to investigate the effect on longitudinal peak membrane strain and deformation length when yield strength increases, see paper 2 and 3. The simulations showed that the peak strain decreases whereas the deformation length increases when the yield strength increases. The studies described in paper 4 and 5 measured roll load, roll torque, springback and strain history during the U-profile forming process. The measurement results were used to validate the finite element model in paper 1. The results presented in paper 6 shows that the formability of stainless steel (e.g. AISI 301), that in the cold rolled condition has a large martensite fraction, can be substantially increased by heating the bending zone. The heated area will then become austenitic and ductile before the roll forming. Thanks to the phenomenon of strain induced martensite formation, the steel will regain the martensite content and its strength during the subsequent plastic straining. Finally, a new tooling concept for profiles with variable cross-sections is presented in paper 7. The overall conclusions of the present work are that today, it is possible to successfully develop profiles of complex geometries (3D roll forming) in high strength steels and that finite element simulation can be a useful tool in the design of the roll forming process.