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532 Uppsatser om Temperature thresholds - Sida 25 av 36
Värmeåtervinning ur spillvatten : En utredning av möjligheterna med spillvattenvärmeväxlare
The purpose of this report is to investigate the possibilities with drain water heat recovery (DWHR) in residential buildings. Information and relevant theory has been collected and summarized in this report. Calculations have been done for given scenarios to evaluate profits. DWHR heat exchangers use simple technology and have long life-time. The heat exchanger is connected to outgoing drainage pipe and incoming cold-water supply so countercurrent flow is accomplished.
New Generation Surface treatment for tools : A preliminary study
The surface finishing technique called black oxidation is currently being used on thetool holders made of low alloyed tool steel produced by Sandvik Coromant. Blackoxidation isn?t considered a sufficient technique because it doesn?t make the toolholders look like the quality products that they actually are. The reasoning behind thisis that the tool holders can show signs of corrosion after prolonged storing times orin countries with high humidity and temperature. The corrosion doesn?t decrease thetool holders performance, but the customers might believe otherwise.
Klimatsimulering av ett kontorsrum : Hur de termiska stigkrafterna påverkar ventilationseffektiviteten
AbstractIn urban societies people spend more and more time indoors, which put great demands on the indoor environment. If the ventilation is to manage the removal of unwanted substances in the indoor air, a good mixing of the air is required. The question arises that, whether the buoyancy forces will counteract a good mixing of the indoor air or not?This report aims to clear up the difficulties whether you need to consider the buoyancy forces or not, when adjusting a ventilation unit. For studying the indoor mixing of the air a two dimensional model is constructed in COMSOL Multiphysics.
Samband mellan tjockleken hos PVD-skikt och förslitningsbeteendet vid svarvning
This project has as main goal to study the influence of the coating thickness, deposited by arc-PVD- technology, on the wear resistance of coated cemented carbide inserts in three different turning operations. An additional effort has also been made to develop a new test method for evaluating flank wear resistance. Three different coating types (Coating A, Coating B and Coating C) have been studied in three distinctive thicknesses (2, 4 and 6 µm) for each type. For two of the coating types (Coating A and B) special studies has been done with the thickest coating, creating two additional coating versions of the thickest coating, by changing various deposition parameters, with the aim to enhance the cohesive properties of the coating and lower the residual stresses at the cutting edge. The results show increased crater wear resistance with increased coating thickness for all coating types, but the amount of increase changes with coating type (Coating A>B>C).
Induktiv provning av ferritiskt rostfritt stå
The report examines the factors which may be a contributing cause to the problems that are present when ferritic stainless steel are eddy current tested in a warm condition. The work is carried out at Fagersta Stainless AB in Fagersta which manufactures stainless steel wire. In the rolling mill there is an eddy current equipment for detection of surface defects on the wire. The ferritic stainless steels cause a noise when testing and this noise complicates the detection of defects.Because of this, a study was made of how the noise related to factors such as steel grade, temperature, size and velocity. By observing the signal and with the possibilities to change the equipment settings the capability to let a signal filter reduce the noise level were evaluated.
Oavsiktlig lindrig hypotermi under operativa ingrepp : En litteraturstudie
Oavsiktlig lindrig hypotermi förekommer hos upp till 60 % av de patienter som genomgår en operation. Hjärnans förmåga att reglera kroppstemperaturen under ett operativt ingrepp påverkas av läkemedel som ges under anestesi. De åtgärder som vidtas innan och under operationen för att minska temperatursänkning är ofta otillräckliga och behöver förbättras. Idag finns få rutiner för hur oavsiktlig lindrig hypotermi skall undvikas för att minska det lidande som kan uppstå då patienten oavsiktligt utsätts för avkylning perioperativt. Syftet med studien var att påvisa de risker och effekter som uppstår i samband med oavsiktlig lindrig hypotermi perioperativt, samt att belysa framkomna skyddande faktorer.
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.
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.
Lönsamhetskalkyl för produktion av gran på markavvattnad och askgödslad myrmark
In Sweden there are about 4 million hectares of bare peat (mire). This land has great potential to be transformed into productive forest land, provided drainage is carried out and, in some cases, even fertilization with ashes. Drainage of mires is necessary because the high groundwater table prevents trees from growing due to reduced oxygen availability. Some of the key nutrients that trees need to grow appear in too small quantities in mires, especially potassium (K) and phosphorus (P). Ash from the combustion of biomass contains these elements and is therefore suitable as a fertilizer.
Oavsiktlig lindrig hypotermi under operativa ingrepp - En litteraturstudie
Oavsiktlig lindrig hypotermi förekommer hos upp till 60 % av de patienter som
genomgår en operation. Hjärnans förmåga att reglera kroppstemperaturen under
ett operativt ingrepp påverkas av läkemedel som ges under anestesi. De åtgärder
som vidtas innan och under operationen för att minska temperatursänkning är
ofta otillräckliga och behöver förbättras.
Idag finns få rutiner för hur oavsiktlig lindrig hypotermi skall undvikas för
att minska det lidande som kan uppstå då patienten oavsiktligt utsätts för
avkylning perioperativt. Syftet med studien var att påvisa de risker och
effekter som uppstår i samband med oavsiktlig lindrig hypotermi perioperativt,
samt att belysa framkomna skyddande faktorer.
Variation in protein precipitation and phenolic content within and among species across an elevational gradient in subarctic Sweden
This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.
Värmeförluster vid utvändigt placerade ventilationssystem
To be able to handle tomorrows need for limited energy consumption we need to reduce our use of energy. The building sector stands for around 40 % of all energy consumption in the society. The government has put up a goal to reduce the energy consumption in our buildings with 20 % by year 2020 and 50 % by year 2050 compared with year 1995. To be able to do reach that goal we need a more energy efficient building stock.The main part of the energy used in our buildings is used for space heating. By installing ventilation systems with heat recovery on the exhaust air it is possible to use the heat-energy in the exhaust air to warm up the incoming air.
Klimatanpassning av mjukpappersfabrik
Denna rapport är en dokumentation av ett examensarbete vid Karlstads universitet våren 2006. Arbetets storlek är 20 poäng varav 5 poäng utgörs av en litteraturstudie.Examensarbetet har gjorts i samarbete med Pöyry. Uppdragsbeskrivningen var att klimatanpassa en mjukpappersfabrik i ökenlandskap. Både för att tillgodose befintliga energibehov och om möjligt minska dem.Fabriken har ett behov av produktionsånga. Solen kan användas för att producera ånga.
Utvärdering och uppdatering av typkurvor
The purpose of this thesis is to evaluate and update load curves for Fortum Distribution AB. Theload curve method is a tool used to forecast the strain of an electric grid. The method is based oncustomer annual energy consumption, outdoors temperature as well as customer category. Theload curve method was established by Svenska Elverksföreningen at the start of the nineties andfocus was put on standardizing annual energyconsumption, in order to make the method usableacross the nation. Present consumption patterns have changed since the original load curves wereproduced, which leads to a need to update the load curves.The work began with an update of present load curves according to recommendation taken fromanother earlier thesis.
Effects of peat and wood shavings as bedding on the faecal microflora of horses
The main purpose of this study was to determine the impact of bedding material on the faecal microflora of horses. Another objective was to investigate the hygienic and physical qualities of the bedding materials used and how these may change in the course of the trial period. The bedding materials used were sphagnum peat and wood shavings. Six horses had each material as bedding for a three week period in a change?over experiment.