2 resultados para Conductive wires

em Dalarna University College Electronic Archive


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Until the beginning of the 1900:th century the paper making process was handicraft. The paper machines that have been developed since then are as impressing in size as fascinating when it comes to the technique. The process has always been improved to give a better paper for lower costs, with as short manufacture time as possible. Stratified forming has been a reality since 1830. From the beginning it was applied to board and paperboard. Now it is also the most common method for making tissue and one paper mill in Austria use it for fine paper. Stratified forming can be categorized as separate forming or simultaneous forming. Separate forming means using several headboxes and sometimes even several wires. Simultaneous forming means using only one stratified headbox. This method has many advantages over separate forming, inter alia improved economy, quality, wood exchange and higher runability of the paper machine. Several experiments have been done with simultaneous forming of different fibres by placing a fibre with high bulk in the middle layer and a smooth fibre on the surface layers. The results has shown that by using this method both the bending stiffness and surface properties are improved, or a lower grammage paper is obtained with maintaining quality. Simultaneous forming can also be used to stratify fillers in layers where they are most efficient. In that way both paper quality and economy is improved. Simultaneous forming is also used for fractionated pulp. Fractionation means separating springwood fibre from summerwood fibre, and placing them in separate layers. Research results of fractionated pulp show about the same result as simultaneous forming of different fibres.

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The purpose of this study is to investigate the most common phonetic and phonological difficulties in the teaching of Spanish as a foreign language. The study has been based on the following questions: Which difficulties can teachers encounter when teaching phonetics and phonology? Which difficulties can students encounter when learning phonetics and phonology? How is phonetics and phonology taught? In order to be able to investigate the difficulties, a questionnaire has been handed out to five experienced teachers. The results of the questionnaires, together with the theory, has been analysed in the analysis. The outcome of the analysis shows that several difficulties can be detected in both the teaching and in the learning process. The results of the questionnaires also show us that the teachers mostly teach phonetics the same way: through repetition and imitation, the conductive method, and very few think outside of the box to encounter new methods.