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4952 Uppsatser om High temperature electronics - Sida 30 av 331
Försämrad korrelation mellan storleken av Kebnekaises sydtoppsglaciär och andra klimatindikatorer
Intergovernmental Panel on Climate Change (IPCC) recognizes glaciers as the best land-indicator of climate change. A variety of studies have concluded, using both modeling and field studies, that above all climate parameters precipitation, particularly winter precipitation, and summer temperature controls the change in glacier mass balance. With global warming almost all glaciers on Earth are losing mass. In this study, the summit-glacier constituting Kebnekaise's south summit (called the Southern-summit henceforth), Sweden's highest point, is studied to see how it is affected by winter precipitation and summer temperature during the period 1968?2013.
Skillnader i kungsörnens (Aquila chrysaetos) flyttningsmönster beroende på ålder och klimatfaktorer : En studie för skyddet av kungsörn
This study examines the factors that influence the seasonal movements of Golden Eagles (Aquila chrysaetos), and can thus provide important information that helps to improve the protection of the species. There were two main purposes of this study. First, I wanted to analyze the difference between preferences of juvenile and adult Golden Eagles in their choice of southern or northern hibernation areas. Do younger eagles prefer moving longer distance to southern areas of Sweden? Second, I wanted to investigate how the climate influenced the choice of date of migration in the fall.
Att vinna eller försvinna när alla får varsin dator : En-till-en-satsningar och dess inverkan på delaktighet, självbild och lärande för gymnasieelever i behov av särskilt stöd
The purpose of this study was to investigate how high school students felt that the computer helped or hindered participation and self-esteem in the learning situation and if the students experienced any differences between when they had been relatively alone in using a computer compared to when everyone had their own computer. The starting point was the national one-to-one projects made to give every student access to a personal computer and how it affected students in special educational needs and previous research. The theoretical approach was based on socioculture/activity theory and theories of self-esteem. Ten high school students in grade one at a senior high school that previously had started up a one-to-one project was interviewed. The results showed that the students primarily used the computer to write and to search the Internet, but even as a alternative or compensatory tool.
Miljö- och hälsoskyddskontorets tillsynsarbete - ur verksamhetsövarens perspektiv
Nanofiltration is a proper way of preparation of drinking water. The process has a lot in common with reverse osmosis where a semipermeable membrane is used to separate a pure water flow from the remaining water. A pilot plant was used to ensure that nanofiltration is a suitable technology for a specific waterworks station in Glemmingebro, Ystad. The purpose was also to find out if a pH-adjustment is needed for feed water in a possible full scale plant. In this case nanofiltration is used mainly to remove sulphate and calcium since the raw water contains concentrations of these substances which exceed the limits for potable water. It is important to receive a high recovery (RC), otherwise the deliviery of water won?t be high enough.
Ny princip för spänningsreglering i Fortum Distributions mellanspänningsnät i Stockholm.
The voltage regulation in Fortum Distributions medium voltage network in Stockholm does not work satisfactory. This results in too high distribution voltages with many customer complaints as a consequence. The reason is the model responsible for compensating for voltage drops in the distribution network. Despite several adjustments Fortum has not been able to find the source of the high voltages and has therefore appointed an investigation in the form of a thesis work.The aim of this investigation is to locate the error and to produce a proposal regarding the solution of this error using the existing system, common industrial knowledge, state of the art research and the option to use voltage readings from the different substations.The conclusion of this master thesis is that the largest contribution to the high voltage levels is made by the large compensation for distribution loses. Furthermore an additional error in the model has been found.
Variationer i normal språklig förmåga hos vuxna jämfört med neural aktivitet
Since the brain is an important prerequisite for human language there is a great interest to gain more knowledge about healthy brain activity during language mediated communication. This study examines variations in high level language ability relating to demographic factors like gender and age and relates language ability to neural activity.Eighteen individuals in ages between 22 and 64 were included and divided into groups in relation to gender and age. The material used to assess language ability was derived from Testbatteri för Bedömning av Subtila Språkstörningar (Laakso, Brunnegård, Hartelius & Ahlsén, 2000), Swedish Lexical Decision Test (Almkvist, Adveen, Henning & Tallberg, 2007) and a reading test (Högskoleprovet). The results were correlated with measured brain activity using functional Magnetic Resonance Imaging (fMRI) and language paradigms. ANOVA was applied to discover possible demographic variances in language ability as well as in brain activity.The results showed no significant differences in language ability.
Större och mindre växtätares samexistens : Möjlig interaktion och effekt på lokal biodiversitet
The purpose of this report was to investigate to which extent local presence of large herbivore mammals (Alces alces, Cervus elaphus, Capreolus capreolus, Dama dama and Sus scrofa) covaries with small rodents (Myodes glaerolus, Apodemus flavicollis and Apodemus sylvaticus? The hypothesis was that high abundance of wild ungulates would inhibit the density of small forest rodents. The data was collected during field work within FoMA (Environmental Monitoring Assessment)/SLU (Swedish University of Agricultural Science). The Ungulate dropping inventory and rodent trappings, which is the base in this report, where performed 2012 ? 2014 in Gnesta/Nyköping municipalities (G/N) with a relatively high density of wild ungulates and Vetlanda/Växjö municipalities (V/V) with relatively lower wild ungulate density.
Studie av materialinnovationer med ett brett applikationsspektra : Tillämpat på Disruptive Materials
This master thesis attempts to answerthe question if a startup with amaterial innovation needs a specialbusiness development model. Mainstreambusiness development literature is notwell adapted to the rigor of testing anew material and bringing it tomarket. This was studied using threedifferent methods. First of thetheories that are considered canonicalfor high tech business development wasexamined. The next step was to go into the role of a business developer inone of the hottest high tech materialinnovation startups this decade,Disruptive Materials.
Effekten av total mängd dietärt fett på lipidprofilen : En litteraturstudie
The effect of total dietary fat on the blood lipid profile: a reviewFat consumption has increased in Sweden in the 21th century, probably due to the advancement of the diet low car high fat (LCHF). Also, cardiovascular disease is the leading cause of premature death in Sweden. Various blood lipids are used to evaluate the cardiovascular disease risk; total cholesterol, LDL, HDL and triglycerides among others. High levels of total cholesterol, LDL, triglycerides and low levels of HDL are believed to increase the risk. The purpose of this review was to examine the effects of high-fat-diet on blood lipids, cholesterol, LDL, HDL the ratio between LDL/HDL and triglycerides through a systematic review.
Metanpotential för alger och bioslam blandat med pappersfiber
In this thesis the methane gas potential of three different substrates, two algaes Saccharina latissima and Laminaria digitata and biosludge mixed with paper fiber was studied. This was done by batch experiments in a laboratory environment to examine the gas production and composition of the produced gas.Biogas production is a complex anaerobic digestion process in which various microorganisms decompose the substrate in steps and at the end produce biogas and a residue. Many factors affect the production of gas, for example the substrate content, temperature and pH in the digester.The analysis of methane potential were divided into two experiments. In experiment 1 substrates were digested along with inoculum from Växjö waste water treatment plant in a temperature of about 37 ?C.
Klimatfaktorers inverkan på granbarkborrens svärmningsintensitet i Medelpad
The spruce bark beetle (Ips typographhus) is one of the 25 000 species of insects in Sweden, an insect of great economic importance because it can alone terminate forest of high value. During the past decade, insights of climate change received with increasing attention. If the future brings a milder climate in the north and therefore a longer growing season, one would think that it would only affect the forestry to the better? Yet in recent time, outbreaks after storm felling seems to occur more frequently. The Spruce bark beetle ruins millions of cubic meter of Norway spruce (Picea abies) in Sweden alone, with more frequent storm felling and a larger amount of wind thrown threes in the forests there will also be room for an advancing reproduction.
Samsung Electronics i medial kris : En Corporate Social Responsibility studie avseende konsumentens förtroende vid en medial kris
De flesta företag är beroende av att gå med ekonomiskt vinst för att överleva, och vid en medial kris är det därför nödvändigt att minska risken för negativ medial rapportering. Detta för att kunna behålla varumärkets kundförtroende. Syftet med undersökningen var att ta reda på om konsumenten uppfattar CSR som en motverkande faktor för kris om företaget Samsung Electronics hamnar i en medial kris, samt hur en kris kan tänkas påverka företagsförtroendet för Samsung hos kvinnor och män. Seungho Cho och Yong-Chan Kims (2011) studerade CSR och de fann att CSR-aktiviteter samt bolagets nationalitet har huvudsakliga effekter på företagets anseende. De är båda positiva faktorer som dämpade deltagarnas och individers vilja att vidta åtgärder mot företaget vid kris (Cho & Kim, 2011).
Utveckling av högspänningskontakt
This report describes the development of a high-voltage connector at the request of Scandinova Systems AB in Uppsala. The development process is described from the making of a customer demand specification, to the making of drawings for the manufacturing of prototypes. Scandinova develops high-voltage modulators, hence the need for connectors that can handle very large power pulses. Their current connector has several weaknesses that may cause the connector to melt or catch fire. The development began with a number of studies that included the modulator structure and the current connector structure and functions.
Layoutgenerator för serie/parallell-omvandlare
I digitala kretsar kan både bit-parallella och bit-seriella interface förekomma.T ex kan en integrerad digital krets (IC-krets) internt använda sig av bit-parallella aritmetiska kretsar medan dess kommunikation med andra integrerade kretsar sker bit-seriellt. Genom att använda seriell kommunikation mellan IC-kretsar kan antalet ben på kapslarna effektivt begränsas.Detta examensarbete gick ut på att göra en layoutgenerator för generering av en parametriserbar serie/parallellomvandlare och en parallell/serieomvandlare. När en krets använder sig av både bit-seriell och bit-parallell representation av data behövs dessa för att omvandla mellan formaten..
Energieffektivisering genom förvärmning av flis till kokare med sekundärvärme
The Swedish pulp and paper industry meets higher demand for energy efficiencyi mprovements with increasing energy prices and changes in the Swedish renewable energy certificate system. One action of energy efficiency improvement is by using secondary heat, that otherwise would have been treated as waste heat, for use in a system with lower temperature demands. The aim of this Master´s thesis is to identify possible secondary heat sources in a typical Swedish pulp and paper mill and to investigate what economic benefits the secondary heat will provide when being used for pre heating of wood chips to a kraft digester.The Master´s thesis focuses on three secondary heat sources; dry warm air, warm water and moisture saturated warm air located inside the pulp or paper mill. Two types of kraft digesters are simulated within this study, a typical Scandinavian digester and a modern twin vessel steam phase digester.Due to quality aspects and low temperature level drying is the drying technology with dry warm air rejected. Using warm water in direct contact with wood chips increases the quantity of water to the evaporation plant and thus reduced pulp or paper production and is therefore also rejected.