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In the research project The interplay between language and thought in understanding problems from a student perspective, we have analysed students’ understandings of a physical event. The investigation is done from a first person perspective since we are interested in students’ conceptualisations. In discussions about the physical event of throwing a ball, students describe the event in different

An increasing demand on load flexibility in power supply networks is the motivation to look at flexible, and possibly optimal control systems for power plants with carbon capture units. Minimizing the energy demand for carbon dioxide removal under these circumstances reduces the cost disadvantage of carbon capture compared to conventional production. In this work a dynamic model in Modelica of a c

Abstract in UndeterminedA numerical study has been performed to simulate the tip leakage flow and heat transfer on the first stage of a high-pressure turbine, which represents a modern gas turbine blade geometry. The low Re k-ω (SST) model is used to model the turbulence. Calculations are performed for both a flat and a squealer blade tip for three different tip gap clearances. The computations we

This paper presents a comparison of the image rejection between Gilbert mixer and the passive mixer. A simple model for mixers is set up, and the image rejection performance of passive and Gilbert mixer is analyzed based on it. Simulations and calculations were done to compare the image rejection of the two mixers. The results show that the Gilbert mixer, comparing with the passive one, shows a st

Popular Abstract in Swedish När en konsument går längs en gång i en butik kan han eller hon enkelt ta ett mjölkpaket utan att tänka på allt som behövts göras för att det ska kunna hamna på hyllan. Många chefer och ingenjörer lägger ner oerhört mycket energi för att detta ska vara möjligt. För varje paket mjölk omfattar kedjan av olika aktiviteter processande, förpackning, transport och lagring, frIn the supply chain interactions with product and packaging systems, actors place various needs on packaging. Satisfying these needs eventually increases the supply chain efficiency and effectiveness. The aim of the research presented is to contribute to the packaging logistics body of knowledge on reducing the gap between the supply chain needs and satisfying them, through packaging design and de

Human-induced climate change presents grave challenges to society. We have to find ways both to mitigate the changes and adapt to them. However, this is not all, for politics climate change represents a problem with large scientific uncertainties. This is evident in the Intergovernmental Panel on Climate Change (IPCC) assessment reports. In this study, scientific uncertainty is discussed and syste

The optimum-seeking (in the sense of maximisation of torque) field weakening control scheme proposed by Kim and Sul (see IEEE Trans. Ind. Electron., vol. 44, no.4, p.512-18, 1997) is developed further. The performance under imperfect field orientation conditions is investigated, and it is shown that an overestimated-rather than an under-estimated-model leakage inductance should be used. A slightly

What happens when global market-oriented models for auditing and quality assessment are taken up by local parishes? The paper is based on case studies where a number of parishes and auditing models provide the object of study. Parishes are to some extent restrictive about embracing new ideas on auditing and quality control. With assistance from neo-institutional theory it can be shown that the co