30 research outputs found

    Ny teknik i fysik : En studie i hur ny teknik och forskning integreras i fysikundervisningen pÄ gymnasiet.

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    Youths do not reflect over how it works but rather focus on how they can use the technology. Earlier research has studied if teacher acquires further education in there topics, not if knowledge about new technology can contribute to a better education. If teachers have good knowledge about new technology and forwarding it to the pupils, can it increase the interest for physics among the pupils? Didactic research has shown that pupils would like to see conjunction with the knowledge they receives and their natural world. Didactic research concentrates on how knowledge is forwarding and not on the subject for the education. Six teachers on six different schools has been interview. On three of these schools has also five pupils been interview on their opinion on if and how new technology has be taken up in their education. New technology is being taken up in the physics education, but it exist no recommendation on how. New technologies are being taken up on the teacher’s initiative, paramountly for that rouse interest at pupils or connect the physics to the pupil's reality. Pupils receive also explanations of new technology when they put questions about it during lessons. The teacher’s apprehension about what is new technology varies. Common for all teachers is that they request better knowledge of their subjects of teaching for that being able to take up new technology with the pupils. They pupils that have interviewed thinks that it is good if new technology is being taken up in the physics education, it gives a better connection to reality.Ungdomar reflekterar inte i första hand över hur ny teknik fungerar utan fokuserar pĂ„ hur man kan anvĂ€nda tekniken. Tidigare forskning har studerat om lĂ€rare behöver Ă€mnesfortbildning, inte om kunskap om ny teknik kan bidra till en bĂ€ttre undervisning. Om lĂ€raren har god kunskap om ny teknik och förmedlar det till eleverna kan det dĂ„ öka intresset för fysik hos eleverna? Didaktisk forskning har visat att elever vill se samband mellan den kunskap de fĂ„r och deras omvĂ€rld. Didaktisk forskning inriktas pĂ„ hur kunskap förmedlas och inte pĂ„ Ă€mnet i undervisningen. Sex lĂ€rare pĂ„ sex olika skolor har intervjuats. PĂ„ tre av dessa skolor har ocksĂ„ fem elever intervjuats för att ge sin syn pĂ„ om de anser att ny teknik tas upp i undervisningen. Studien visar pĂ„ att ny teknik tas upp i fysikundervisningen, men det finns inga rekommendationer pĂ„ hur. Ny teknik tas frĂ€mst upp pĂ„ lĂ€rarens initiativ, frĂ€mst för att vĂ€cka intresse hos elever men ocksĂ„ för att koppla fysiken till elevens verklighet. Elever fĂ„r Ă€ven förklaringar av ny teknik nĂ€r de stĂ€ller frĂ„gor om den under lektioner. LĂ€rares uppfattning om vad som Ă€r ny teknik varierar. LĂ€rare efterfrĂ„gar bĂ€ttre Ă€mneskunskaper för att kunna ta upp ny teknik med eleverna. De elever som har intervjuats tycker det Ă€r bra om ny teknik tas upp i fysikkurserna, det ger en bĂ€ttre koppling till verkligheten

    Towards energy efficient heating in industrial processes - Three steps to achieve maximized efficiency in an induction heating system

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    The demand for energy efficient heating solutions can be met by a new concept technology of induction heating. The concept technology relies on inductors built on litz wires moulded in soft magnetic composite. The aim of this article is to present and verify a hypothesis for greatly improved induction heating efficiency when modifying a traditional inductor design. The verification performed using analytical solutions, FEM simulations and experimental work, clearly shows higher heating efficiency compared to traditional heating inductors. The work also shows a significant reduction of magnetic stray field when flux concentrator is used, given a certain heating power

    Angiotensin Converting Enzyme (ACE) Inhibitors and Heart Failure: The Consequences of Underprescribing

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    Heart failure (HF) is a common and expensive cardiovascular disease, in economic terms as well as in lives lost. Angiotensin converting enzyme (ACE) inhibitors have been shown to significantly reduce mortality and hospitalisation in HF. However, recent surveys show that the prescription rate of ACE inhibitors for HF is far below what is considered to be optimal. Furthermore, prescribed dosages are usually lower than those recommended based on evidence from clinical trials. This article estimates the consequences, both economic and human, of underprescribing ACE inhibitors in patients with HF. The indication for prescribing an ACE inhibitor varies, and clinical trials have included different categories of patients; it is inappropriate to assess costs in all eligible patients without taking these factors into account. Therefore, we analysed the data with respect to 4 different groups: 1. asymptomatic left ventricular systolic dysfunction (LVSD) - an early stage leading to chronic HF; 2. chronic HF; and post-myocardial infarction (MI) LVSD differentiated into 3. post-MI asymptomatic LVSD and 4. post-MI chronic HF. We also estimated the cost effectiveness of adding an ACE inhibitor to the treatment of patients with HF for whom an ACE inhibitor is not currently prescribed. If only patient populations in which large trials have shown a significant effect of ACE inhibition on mortality are included in the analysis (i.e. excluding asymptomatic patients with LVSD), increasing the number of Swedish patients receiving an ACE inhibitor could save in excess of 3700 lives each year, in addition to reducing the annual number of hospitalisations by 8400. The additional cost would be 101.5 million Swedish kronor (SEK), a cost per life saved of SEK27 200. Chronic HF is the most cost-effective patient population to treat, generating cost savings under certain assumptions. A further 6700 hospitalisations can be avoided should the use of ACE inhibitors be extended to asymptomatic patients with LVSD. Increasing dosages to those used in the large clinical trials may generate additional savings in lives and hospitalisations. In conclusion, the use of ACE inhibitors in HF and LVSD has clearly been proven to be cost effective, and compares favourably with the cost effectiveness of treating hypertension or hypercholesterolaemia. At present, however, ACE inhibitors are not optimally utilised. Given the increasingly constrained resources for healthcare, every effort should be made to increase the use of cost-effective treatments, such as ACE inhibitors in chronic HF and post-MI LVSD.Reviews-on-treatment, Prescribing, Pharmacoeconomics, Heart-failure, ACE-inhibitors, Drug-utilisation, Cost-effectiveness

    Residual life estimations of pavements : a survey of knowledge, needs and applications to reduce LCC in design, procurement, construction and management stages

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    I rapporten utreds hur begreppet restvÀrde kan anvÀndas vid investeringar i vÀgar ochvÀghÄllning för att analysera tekniska lösningar eller utforma krav för upphandling.Syftet Àr att utarbeta ett ramverk med principer som knyter samman ekonomiska övervÀgandenoch teknisk dimensionering, som i sin tur kan bidra till mer optimala investeringari vÀgar ur ett lÄngsiktigt perspektiv. Rapporten Àr avgrÀnsad till investeringar ivÀgkroppen, men paralleller dras till andra omrÄden.Inledningsvis granskas begreppet och vilka behov som föreligger. RestvÀrde kan sÀgasspegla framtida nytta med en vÀganlÀggning minus kostnader för förvaltning. För deflesta tillÀmpningar kan nyttan antas lika medan vÀghÄllarkostnaderna pÄverkas av olikatekniska lösningar. DÀrmed reduceras problemet till att frÀmst fokusera pÄ kostnader förframtida drift och underhÄll. I rapporten redogörs för hur nedbrytning kan prognosticerasoch ÄtgÀrdsbehov förutsÀgas. Denna information ligger sedan till grund för ettramverk för bedömning av framtida kostnader för drift och underhÄll av vÀgar. Slutligenutarbetas förslag pÄ hur denna kostnadsuppskattning och tillhörande restvÀrdesbedömningkan tillÀmpas inom upphandling pÄ funktion, ersÀttningsmodeller samt meroptimerad vÀghÄllning ur LCC-synvinkel.This report deals with a concept applying residual value estimations to applications in optimisation and procurement of road construction and maintenance. The purpose is to develop a framework and concept for tieing together technical and economical considerations in order to contribute to more optimised construction and maintenance of roads in a long-term perspective. This report is limited to investments in the pavement. Initially, the term residual value and its application in this context is investigated. Then, possibilities for prediction of pavement deterioration and performance are presented. These models are also linked to prediction of maintenance needs. Finally, a concept for cost predictions is developed with corresponding residual value applications, for example performance procurement, payment models, as well as more optimised pavement management from a life cycle perspective

    Cooling of Litz Wires in Industrial Induction Heating Applications

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    Induction heating has the potential to be a very efficient heating method and by using litz wires instead of copper tubes the losses can be significantly reduced. The drawback with litz is the fact that it comprises insulation materials with low temperature resistance, typically in the range 150 – 200 °C. In order to solve this problem a solution is to create channels in the litz structure in which a cooling medium can flow. In order to investigate the possibility with cooled litz wires a number of litz wires were manufactured with different types of internal cooling channels and infiltration materials. The experiments showed that it was possible to maintain a steady state temperature of the litz wire below 25 °C at a current density of 10 A/mm2 and frequency of around 20 kHz. A thermal FEM model was developed in order to calculate the equivalent thermal conductivity of the litz structure based on the measurements. The induced losses in the cooling tube was also investigated with an electromagnetic FEM model showing that the choice of dimensions and material for the cooling tube might be crucial for the heating efficiency

    VGU-guiden : VÀgars och gators utformning - Stödjande kunskap

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    I VÀgars och Gators Utformning (VGU) beskrivskrav och rÄd för utformning av den fÀrdiga vÀg eller gatuanlÀggningens egenskaper. Kraven i VGU ska anvÀndas vid utformning inom Trafikverket och Àr rÄdgivande för kommuner. VGU:s krav- och rÄdsdokument ska uppdateras löpande utifrÄn ny kunskap inom vÀg- och gatuutformning. Antalet sidor i VGU har de senaste Ären minskats genom att arbetsgÄngar och detaljrikedom i ÄskÄdliggörandet av kunskap har reducerats. Det finns dÀrför ett behov av att ge stöd för hur VGU ska tillÀmpas dÄ vÀg- och gaturum ska formas, vilket Àr bakgrunden till att VGU-guiden har tagits fram som stödjande handböcker. Arbetsmetodik och bakgrundskunskap har nu inarbetats i VGU-guiden. Denna handbok beskriver en fördjupning av kunskap inom vÀg- och gatuutformning och som inte finns beskriven i VGU:s krav- och rÄdsdokument eller i andra handböcker. InnehÄllet i Stödjande kunskap ska baseras pÄ etablerad kunskap som har en tydlig koppling till kraven och rÄden i VGU

    VGU-guiden : VÀgars och gators utformning - Stödjande kunskap

    No full text
    I VÀgars och Gators Utformning (VGU) beskrivskrav och rÄd för utformning av den fÀrdiga vÀg eller gatuanlÀggningens egenskaper. Kraven i VGU ska anvÀndas vid utformning inom Trafikverket och Àr rÄdgivande för kommuner. VGU:s krav- och rÄdsdokument ska uppdateras löpande utifrÄn ny kunskap inom vÀg- och gatuutformning. Antalet sidor i VGU har de senaste Ären minskats genom att arbetsgÄngar och detaljrikedom i ÄskÄdliggörandet av kunskap har reducerats. Det finns dÀrför ett behov av att ge stöd för hur VGU ska tillÀmpas dÄ vÀg- och gaturum ska formas, vilket Àr bakgrunden till att VGU-guiden har tagits fram som stödjande handböcker. Arbetsmetodik och bakgrundskunskap har nu inarbetats i VGU-guiden. Denna handbok beskriver en fördjupning av kunskap inom vÀg- och gatuutformning och som inte finns beskriven i VGU:s krav- och rÄdsdokument eller i andra handböcker. InnehÄllet i Stödjande kunskap ska baseras pÄ etablerad kunskap som har en tydlig koppling till kraven och rÄden i VGU
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