Fossil fuels are affecting our climate negatively and there is a limited amount of them in the world, which leads to the importance of finding alternative fuels. One alternative is biogas, which is produced though a digestion process of different organic materials in a biogasreactor. Organic substrate that comes from farms has the biggest potential to increase the production of biogas in Sweden. Primarily crops from farms, but also waste products like manure are of great importance.Today there is a calculated theoretical potential for biogasproduction of 14TWh per year, which is around ten times larger than Sweden?s production today.

Jag har undersökt vilken matematisk kommunikation som förekommer i förskolebarnets bygglek. Jag valde metoden videoinspelning där jag observerade fem olika bygglekssituationer som jag sedan tolkade och analyserade. För att få en större förståelse kring byggmiljön ställde jag också några frågor till pedagoger som ansvarade för konstruktionsverkstaden. Resultatet visade att det konkreta materialet förstärkte översättningsledet från det barnet redan kan (första ordningens språk) till det barnet ännu inte förstår (andra ordningens språk). Pedagogerna kunde med materialets hjälp göra ett matematiskt begrepp konkretare.

En studie om det laborativa materialet i bråkundervisningen utifrån elevernas perspektiv Författare: Ruzica Pajic Syftet med denna studie är att uppnå en djupare förståelse om det laborativa materialets betydelse i skolans matematik. I detta magisterarbete har det undersökts hur barns perspektiv påverkas i årskurs 6 utifrån hur laborativt material används i matematikundervisningen. I tidigare forskning redovisas barns lärande och hur den skildras utifrån kognitiva, kulturhistoriska och sociokulturella perspektiv. Bland dessa perspektiv presenteras och jämförs teoretikerna; Vygotsky och Bruner med varandra. Dessa teoretiker har valts, eftersom de presenterar grunderna för användning av laborativt material i skolan.

Problem areaAlfa Laval is a world leading company in the heat transfers area and have the vision to continue to be that in the future as well. The company has a lot of press lines where the utilization is high and also has started to become old. Prognosis shows that there is an increased demand of heat exchanger in the future. This increased demand is not something that existing lines will manage. To build new lines cost a lot of money and take time so it is essential that new lines are correct from the start and not need to be rebuilt or a lot of time spent to trim it.GoalThe goal is to achieve 100% theoretical utilization of the press (the press shall press the amount of plates it is designed for).

In this paper we analyze a social network specifically designed for the elderly, people with Dementia and people with generally low computer experience. This is a relatively unexplored use for such software, and our goal is to find out whether the technique to be used is simple enough to use for the intended user group, and generally how the whole situation is experienced by the users. To achieve this we conducted an expert evaluation and interviewed a number of users at two separate occasions during their first weeks with Modernfamilies. We came to the conclusion that this software generally is simple enough to use for the intended target group. Some of the users we came in contact with experienced the software as a positive addition to their daily lives, while some could not see any reason for a further use.

AbstractThe purpose of my study is to compare Sten Rydhs wiew of learning disabilities in mathematics and his education with current literature and research. I want to explore whether the education of ?Mattesmedjan?*, influenced by the Suzuki method, can be the solution for the students with maths problems. ?Mattesmedjan? is a privately-owned school of maths.

The aim of this project is to find a concept solution for a wireless transmitting system, installed to transmit data from a hydrophone of the ocean floor down by a wave power generator to the office on shore. The project is a literature review in which previous observations and tests are analyzed and put together to find a solution. The result was a comprehensive solution that includes an acoustic modem to transfer captured information from the bottom to the surface, wirelessly through the water. The information is then sent fron the surface on radio waves through the GSM network to the office on land. Between under and over water there are components to convert information between acoustic waves and radio waves, but also various types of modulation, such as amplitude and frequency modulation is required..

Syftet med projektet är att ta fram en metod för optimering av cellodlingsmedia som kan minska den tid och de resurser som dagens metoder kräver. Fem stamlösningar med adekvata komponenter designas och kombineras med olika flödeshastigheter till ett medium. Kombinationerna testas med experimentell design och analyseras med multivariat dataanalys för att få fram optimerade cellmedia.Odlingsmetoden som de fem stamlösningarna anpassas till är fed-batch, ett system där en av lösningarna är en baslösning och de resterande fyra designas till feedlösningar. De senare tillsätts i olika hastigheter till baslösningen anpassat efter cellernas näringsbehov. Strategin som har lagts upp för att designa stamlösningarna bygger på förhållandet mellan komponenternas förbrukningshastighet i de olika tillväxtfaserna.

This paper is about the extent to which simplified penetration calculations ofsmall-caliber projectiles is a useful tool for assessing the physical protectioncapability. The work should be seen as an attempt to create an accessible tool inthe form of a simplified equation that allows for a better and safer use of thenaval vessels. The tool will also be used at different levels so that decisions andinstructions could be clearer.Performed calculations show a very limited capacity of a ship's basic design interms of physical protection against the use of small-caliber projectiles.How do we know that the calculations correct? By verifying the calculations withpractical shooting tests, a substantial condition to answer the question will becreated. To shoot against a material with two different thicknesses estimated toproduce perforation and non-perforation is a good approximation of the equationusability in the context..

For many years, I have tried to understand why students end up in difficulties in mathematics. As a future teacher, it is extremely important to have knowledge of the various factors that leads to difficulties in mathematics. As a teacher it is obvious to meet the students who find mathematics a difficult subject, and, therefore it is necessary to have a broader knowledge of how to respond and support these students. According to Ahlberg, number of students with mathematics difficulties is increasing every year, therefore, it is important to help students and organize a supporting school environment that promotes and encourages learning (Ahlberg 2001, p. 104-105).

The task given to us was to develop an industrial wheel with new thinking in terms of fresh design and construction, with the ability to brake. While the produced wheels of today only own the property of total braking, a wish was made to integrate the ability of directional locking.The time spent working with the project has been filled with multiple sketches of ideas and function analysis.Choices of material and ways of construction have been verified by calculations, tests and prototype building. The goal of this thesis has been to develop a unique caster with well thought-out design that would be adaptable to different areas of applications.The result was a hubless wheel with the ability of directional locking before total braking.A prototype of the wheel has been made to show the design and functions..

The aim of the present study was to investigate the effect on growth of foals on two different diets, either a forage-based diet or a diet containing approx. 40 % concentrate. The report also includes a review of the pertinent literature on the effects of diet on mares? milk and growth of horses. The hypothesis of the study was that a forage based diet will result in a similar growth pattern as a diet including more concentrates if the diets contain the same amount of energy, crude protein, lysine, calcium and phosphorous.

The city of Kalmar has a desire that their 3D maps of the city should come to a greater use and get residents more involved in Kalmar city. The purpose of this report is to show one way to work with these 3D maps when it comes to presenting information about Kalmar for its residents and tourists in a specific area.  The report also includes information about advantages and disadvantages with the use of 2D and 3D maps in different environments. Various reports and other sources indicate an interest in 3D and a use for this, but even that 2D is still seen as a natural way to read a map. By collecting information from relevant literature, interviews and user testing, the group has obtained sufficient background information to present the results of a web site, where the visitor can navigate in both 2D and 3D in a specific area of Kalmar. User tests and surveys have been conducted in two rounds and the web site has been revised after their results..

The key elements of sourdough fermentation are the presence of active lactic acid bacteria (LAB) and yeast. Sourdough fermentation originates from the ancient Egypt. One theory concerning its onset states that a portion of bread dough was set aside to be baked at a later date and started to ferment spontaneously.Sourdough may contain a wide variety of microorganisms, mainly dominated by LAB and yeast. There are over 50 species of LAB that has been identified in various sourdoughs and more than 20 species of yeast. Sourdough fermentation has been shown to have various impacts on baked cereal good, most of which are attributed to LAB.This study addresses some effects of LAB from fermented milk products in sourdough and sourdough bread.

Syftet med detta examensarbete är att utveckla en datorlaboration baserat på aktiv ljudreglering för kursen reglerteknik allmän kurs för maskin och farkostteknik vid Kungliga Tekniska Högskolan KTH. Arbetet ska innefatta en utveckling av en matematisk modell av rörsystemet som ska regleras med en lead-lag regulator. Rörsystemet vid Marcus Wallenberg Laboratoriet ska användas som modellsystem, och den matematiska modellen ska baseras på mätningar insamlade på detta system.Den matematiska modellen skapades med hjälp av ett s.k. identifieringsexperiment och identifieringen baserades på en viktad minsta kvadratanpassning av insamlade frekvensdata. Modellen anpassades till en överföringsfunktion som visade sig ha ett nollställe i komplexa högra halvplanet, vilket motsvarar en svår bandbreddsbegränsning för den aktiva ljuddämpningen.