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139 Uppsatser om Peak Oil - Sida 2 av 10

Tidsupplösning vid miljövärdering av fjärrvärme : Kontorsbyggnad med solvärmeproduktion - en fallstudie

The demand for environmental assessments on buildings and energy consumption is increasing as well as the energy performance requirements for buildings. At the same time it is increasingly common with self-producers of heat and electricity generation.The main purpose with this master thesis is to investigate how time resolution affects the environmental assessment of energy consumption in office buildings connected to district heating (DH). Environmental assessments were done with both attributional LCA and consequential LCA with system expansion.Fortum´s DH system in Stockholm was analyzed and district heating production was simulated in a Matlab-model. Greenhouse gas (GHG) emissions for the production were calculated. The heat demand of the office Gångaren 16 in Stockholm was simulated in IDA ICE.

Effekten av verbal feedback på maximal isometrisk armbågsflexion

Under idrottsliga aktiviteter, är det kutym bland deltagare och åskådare att ge verbal feedback till andra eller till sig själv med syfte att förbättra prestationen. Vissa använder verbal feedback, andra inte. Vad ger då detta för effekt? Är dessa två fenomen, verbal feedback och prestation, på något sätt relaterade till varandra? Resultat från en sådan studie, skulle vara fördelaktig för idrottare på alla nivåer, såväl som för idrotts- och rehabiliteringsforskning som baserar sina fynd och metoder på empiriska resultat erhållna från mätningar av individers förmåga att utveckla kraft under olika förhållanden. Huvudsyftet med denna studie är att undersöka effekten av verbal feedback på en maximal isometrisk armbågsflexion.

Att vårda ett brustet hjärta : Kvinnors upplevelse av stöd vid akut hjärtsjukdom

Syfte och frågeställningarStudien genomfördes med syftet att specificera vilken intensitet och duration vid uppvärmning som är optimal för att få ut största möjliga effekt vid anaerob prestation i form av maximalt vertikalhopp och fem sekunders maximal cykelsprint. Studien byggde på tre frågeställningar: På vilket sätt påverkar uppvärmningen prestationen vid ett maximalt vertikalhopp? På vilket sätt påverkar uppvärmningen prestationen vid ett maximalt fem sekunders sprinttest? Vilken uppvärmning är optimal för maximal muskulär explosivitet?MetodDesignen var en kvantitativ experimentell studie som innefattade fyra fysiskt aktiva kvinnor med genomsnittsålder på 24 år. Testerna bestod av nio tillfällen där en slumpad uppvärmning på ergometercykel genomfördes varje gång. Därefter genomfördes tre vertikalhopp, så kallade counter movement jump, på en kraftplatta och tre fem-sekunders sprint (5sCST) på Monarks Peak Bike.

Konditionstester i rehabiliteringssammanhang : - En litteraturöversikt

During the past few years there has been an observed decrease in physical fitness within different patient groups. As a part of the rehabilitating physiotherapy treatment it is important to acknowledge the physical condition of the patient. Physical fitness testing might be difficult due to physical limitations within different patient groups. A broad range of exercise tests is therefore of importance in clinical practice. The aim of this overview was to describe exercise tests used in rehabilitation contexts, and to define areas of use and restrictions.

Effekten av betainsupplementering på prestationsförmågan hos vältränade cykelatleter

Bakgrund: Syftet med denna studie var att undersöka effekten av sju dagars tillskott av betain (2,5 gram/dag) på prestationsförmågan i idrottsspecifika tester för manliga vältränade cykelatleter.Metod: Sex (n=6) manliga testpersoner (genomsnitt ± standardavvikelse ålder, 31,7 ± 10,2 år; längd, 188,2 ± 3,6 cm; kroppsvikt; 82,5 ± 7,6 kg; fettfri massa, 71,6 ± 7,3 kg) genomförde förtester bestående av fem counter movement jumps, fyra stycken 12 s wingate-sprinter med 2,5 minuters aktiv vila följt av fem ytterligare counter movement jumps. De blev sedan indelade slumpmässigt i betain- eller placebogrupper. Första testet etablerade basvärden och eftertest ?1? samt ?2? föregicks med antingen sju dagars tillskott med placebo (2,5 g maltodextrin plus 12,5 mg riboflavin) eller betain (2,5 g trimetylglycin plus 12,5 mg riboflavin). Riboflavin användes för att undanröja den fiskliknande doften som kan uppstå vid tillskott av betain.

Geotermisk fjärrvärme i Gunsta

Gunsta is situated about 10 km east of Uppsala. Today there are plans to establish 1000 new households in Gunsta before year 2030. The required energy for heating houses and water would be distributed via a district heating system, which also includes 200 existing residences. The annual required energy, according to this study, would be 16.2 GWh with a maximal peak effect of 6.9 MW. To meet this need, the study suggests a system with heat pumps to upgrade the 31?C water from a 1.8 kilometre deep borehole.

Dimensionerande vattenförbrukning och dess variationer

I Sverige användes det år 2010 ca 907 miljoner kubikmeter dricksvatten från kommunala uttag. Allt detta vatten måste kunna transporteras, vilket görs genom vattenledningar. För att dimensionera dessa krävs att man vet hur mycket vatten som skall distribueras och hur det varierar bl.a. beroende på när under dygnet, veckan och året som uttag sker.Vid dagens tillvägagångssätt för dimensionering av vattenledningar till nya områden använder man bland annat typexempel på förbrukningsvariationer under dygnet för ett liknande område. Dessutom används erfarenhetsbaserade värden på maxtim- och maxdygnsfaktorer.Dagens dimensioneringsätt har ej kunnat säkerställas på grund av otillräcklig och bristfälligt detaljerad data över förbrukningsmängd.

Quantification of sleep in dairy cows in three different stages of lactation

The aim of this project was to quantify the total sleep time in modern dairy cows during24-hour periods and to investigate whether the total amount of sleep as well as timespent in different sleep stages varies between the dry period, early- and peak lactation.The distribution of sleep time between night and day was also examined. Furthermore,correlations between sleep and lying time, fluctuations in body temperature and heartbeat were included in the aim. Eight dairy cows of the Swedish Red breed were used inthis study, which was carried out between June and September 2010. In order toquantify sleep non-invasive electrophysiological recordings were performed.Simultaneously with collecting sleep data, body position and body temperature werealso recorded. No heart rate data was obtained due to difficulties of maintainingelectrodes for heart beat measurements attached to the skin.

Tame animals in the wilderness : livestock grazing around summer farms in Jämtland, boreal Sweden 1800-2011

The forest and mire landscape surrounding the north Swedish villages have been of fundamental importance through time for the farmers. In the Scandinavian summer farm system the forest and mire pasture was used to its full potential. The system consisted of smaller summer farms some kilometres from the main farm in the village, and were the livestock grazed in the forest around the summer farm. The livestock affect their environment, and grazed forests generally contain a higher biodiversity than an ungrazed forest. The overall aim of this thesis is to understand the impact of livestock grazing on a northern forest ecosystem over a long time period.

Vad är Peak Oil och existerar det? : En kritisk lingvistisk av tryckta svenska medier

The purpose of this study is the reports of Peak Oil in Swedish newspapers. In otherwords, how do the news portray or describe the concept and what sources are usedwhen writing articles. With this in mind, I have studied eight published articles in threeSwedish newspapers, Dagens Nyheter, Dagens Industri and Svenska Dagbladet. To studythese articles I've used a qualitative content analysis, as a method, or more specific aCritical Discourse Analysis (CDA). This method was chosen due to it's tools to examinethe text itself and to reveal the structures, unconscious meaning and power of words.Further more I have used theories as agenda-setting (including framing and priming),ideology and newsworthiness to complement the study.The result from the content analysis shows two evident ideologies, one with aneconomic perspective and the other with an environment perspective ? with resourcelimitation in mind.

Inverkan av betessläpp på celltal och mjölkkvalitet hos mjölkkor :

In Sweden regulations stipulates that dairy cows are kept on pasture, or given the opportunity to spend time outside during a coherent period of between two to four months, depending on region. The transition out to pasture is a big change from the winter period in the stable, especially for the modern high yielding dairy cows. The let out to pasture includes a change in feed, environment, and new routines. There are indications that the milk somatic cell count (SCC) rises in a peak shortly after the let out. The purpose of this study was to see if peaks in the SCC could be observed after the let out, and to study the contribution of inflammatory cells (neutrophils) and if the milk composition are affected. The study included 35 cows that were kept in stable during the winter.

En studie av miljöfaktorers betydelse för förekomsten av Francisella

This thesis aims to analyse relations between the risk of Francisella in endemic areas and environmental variables. The thesis also discusses relations between occurrences of Tularemia and meteorological factors. The analysis resulted in several significant models that explained the occurrence of Francisella. These models can however only be applied to the year 2004 since there were too few test performed the other years, therefore no comparisons could be made. Another conclusion was that the relative humidity was significally higher in the year 2003, the same year as the occurrences of Tularemia was at its peak. .

Bilens förändrade förutsättningar i framtidens städer : en studie om aktuella förändringar kring privatbilismen i västvärlden och hur trafikplanering i Öresundsregion förhåller sig till rådande trender

Syftet med denna uppsats har varit att få en förståelse för vad pågående förändringar kring bilanvändning innebär för stadsplanering i västvärlden. Denna uppsats lämnar ingen lösning utan ska ses som inlägg i en pågående och högaktuell diskussion kring bilens roll i staden. För att uppnå detta syfte har en litteraturöversikt samt en intervjustudie med sju trafikplanerare från Köpenhamn, Malmö, Helsingborg och Lund genomförts. Bilen och dess normer har sedan 1950-talet präglat städer och stadsplanering. Bilism har i stor utsträckning bidragit till klimatpåverkan och urbanisering. Något som sin tur har resulterat i urbana fenomen som förtätning och stadsutglesning, påtagliga både i en global kontext och ner på nationell och lokal nivå.

Effects of biogas residues on respiration and denitrification in arable soil : evaluation of methods, microbial activity and agronomic implications

Agricultural soils constitute the base in human food production and soil content of organic matter and plant nutrients together with soil microbial activity are all important parameters for high crop yield of good quality. These parameters are dependant on proper fertilization.Anaerobic digestion of organic wastes for biogas production generates a liquid residue called biogas residue (BR). It contains organic material and plant nutrients which makes ita potential fertilizer for arable cropping. However, it also contains heavy metals and toxic organic compounds and it is therefore in need of evaluation before usage.Microbial tests were performed aiming to evaluate the agronomic traits of four different BR and to find a viable procedure for evaluating slurry fertilizers. Two experiments where soil respiration and soil potential denitrification activity (PDA) was measured at fertilizer addition were performed.

Optimering av sintrade kugghjul

Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.

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