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574 Uppsatser om Temperature gradient - Sida 30 av 39

Effektivisering av energianvändningen i en förskola

This rapport contains an examination of the energy consumption of a kindergarten, which areas that have the largest impact on the energy consumption and what can be done to reduce those areas in ways that are relatively easy and profitable. It is also analyzed if it is possible to reduce the energy consumption from today?s consumption to a consumption that fulfils the demands placed on low energy houses by FEBY.The focus has been on reducing the energy consumption of the areas ventilation, heating system and hot water system, since those seemed to be the easiest ones to affect and since the building is quite recently built.There are different kinds of ventilation systems, at the moment the building have a CAV-system, which means that the ventilation is too high during large parts of the day. There are different ways to manage the ventilation system, for example presence detection, humidity sensors, CO2 sensors, temperature sensors and season adjustment. Many of those are in the end dependent on CO2 sensors to guarantee a good indoor climate, therefore the focus have been placed on this system.

Hur enkel- & dubbelportsturbin i kombination med två olika avgassamlare påverkar gasväxlingsprestanda på en Scania V8

The exhaust arrangement on a Scania V8 consists of one manifold at each bank connected to a twin entry turbine (8-2-2). A study in GT-Power has shown improved performance and reduced cylinder to cylinder variations using two manifolds at each bank in combination with a single entry turbine (8-4-1). This thesis work analyses the difference in performance shown in simulation and verify it by engine test.The initial work was focused on simulation in GT-Power. Investigating how exhaust manifold volume and pulses effects the turbine efficiency and the mean effective pressure during the gas exchange. To verify GT-Power simulations four engine tests with different exhaust arrangement have been made.The results from GT-Power simulation indicate that a larger exhaust volume improve the turbine efficiency.

Styrsystem : För en forskningsutrustning

The division of Engineering Materials at Linköping University, department of Management and Engineering, conducted a research project concerning Fatigue life of thermal barrier coatings during 2009. During this project equipment to provoke these fatigue failure by rapidly heating and cooling test subjects in cycles, was ordered.Design and manufacturing of the equipment was handled internally at LIU.The equipment was built using a furnace that is lowered and raised over the table where the test subject is placed. To keep the temperature of the furnace a lid slides in place to close the downward facing opening of the furnace when it is in the raised position. On this door there is nozzle that is used to cooling of the test subject by air.To make sure that the equipment can work independently you need an automation controller that can evaluate if movement can occur without danger of collisions. The control system also needs to monitor that all elements are performed according to plan.This degree project is based on a modular system from OPTO 22 and includes the configuration of a PLC that will be supplied with logic and a user interface.The degree project resulted in a graphic interface in which a user can set desired values for different parameters and get information about current values for them.

Foraging behaviour of cattle, sheep and goats on semi-arid pastures in Kenya

ABSTRACTThe principal aim of the study was to compare the feeding behaviour of cattle, sheep and goats on pasture and explain any differences between speices. Furthermore, I compared foraging behaviour between dry season and the beginning of the rainy season, in order to see any relationships between weather and behaviour.The study was carried out in Shompole in southern Kenya. Behavioural data were collected by observing herds of cattle, sheep and goats on pasture. The livestock were herded on pasture during the days and kept in bomas, where people live, during the nights. The weather in Shompole is characterized by high ambient temperature and low, bimodal rainfall.

Analys av off-design prestanda för ett absorptionskylsystem

This master thesis project at KTH is performed in the Mechanical and Aerospace Engineeringdepartment at University of Florida (UF). The thesis is a small part of a gas turbine researchproject where a vapour absorption refrigeration system (VARS) and a high pressure regenerativeturbine engine (HPRTE) are integrated together. The main objective is to build a computermodel of the VARS. The computer model is supposed to be used to analyse the off-designperformance of the VARS and should also be easy to integrate as a subroutine in a more complexsystem model. To model the VARS some knowledge of the absorbent/refrigerant mixture had tobe well known, in this case a mixture of ammonia and water.

Samband mellan vattenkemi, ekosystemstruktur och -funktion i två dagvattendammar

Dagvatten bildas då regnvatten inte kan infiltrera marken på grund av hårdgjorda ytor såsom vägar och hustak. Dagvatten är ofta kontaminerat av metaller, näringsämnen och andra föroreningar och bör därför renas i en anläggning innan det når recipient. En allt populärare metod för att omhänderta dagvatten är att anlägga dagvattendammar. I dammarna renas det inkommande dagvattnet genom flera olika processer, varav sedimentation är den viktigaste. År 2006 startades projektet NOS-dagvatten (Norrortskommuner i samverkan) i syfte att erhålla ökade kunskaper om funktionerna hos fem dagvattenanläggningar i Stockholmsområdet. I detta arbete utreds sambandet mellan den kemiska vattenkvaliteten och ekosystemens hälsostatus i Ladbro- och Tibbledammen som ingår i NOS-dagvatten.

Stubblyftningens initiala effekt på emissioner av växthusgaser från en granmark i Småland :

In order to reduce greenhouse gas emissions from human activities fossil fuels will have to be replaced with renewable energy alternatives, such as bioenergy. Sweden has a great potential to produce bioenergy derived from forest products and there is currently a great interest within Sweden in using stumps for bioenergy production. However, the environmental consequences of the method need to be investigated before stump removal can be performed on a large scale. Swedish forest soils contain large carbon pools and a different land use may change conditions so that soils that presently act as sinks of carbon could potentially turn into sources of carbon release instead. This study investigates the initial effects of stump harvesting on the emissions of three greenhouse gases, carbon dioxide, methane and nitrous oxide. The emissions were measured from the soil surface in a Norway spruce forest located in the southern part of Sweden.

Halvledare för höga strömmar i fordon

Mechanical relays are more and more being replaced with semiconductortechnology. In this thesis it is investigated if and how the larger loads couldbe controlled by transistors. The main part of this work aims to create andverify a solution that can control the starter motor, as well as protect it incase of any failure. The different malfunctions that the solution protectsagainst is high current, too high peak current, low current, maximum cranktime and minimum cool off time. The timers also protect indirectly againstoverheating of the starter engine.The transistors used are BTS555, from Infineon.

Sensory profiling of Swedish white wines and a contextual analysis of Swedish viticulture

The aim of the study is twofold, to generate a sensory profile of Swedish wine today and to investigate the opinion of both wine producers and wine experts on viticulture in Sweden and wine from grapes grown in Sweden, achieved through a contextual analysis comprising a literature study and interviews with wine producers in Sweden and Denmark and wine experts from Sweden and Germany, and a sensory analysis at the company Ipsos. ?Mixed methods? was the chosen research strategy as the semi-structured interviews gave qualitative results and the sensory analysis would give quantitative results displayed as spider charts. There is a lack of studies investigating how the Swedish wine is perceived by consumers and consumers might be unaware that the Swedish wine, established through ?trial and error?, is increasing in quality every season, creating a need to display the sensory profile of Swedish wine to strengthening the perception of Swedish white wine. This study shows that the Swedish white wine today is a wine with a fresh, citrusy and flowery aroma and a fresh, citrusy and green apple taste, however, a sensory analysis cannot show if the attributes are those that are desired by the customer, a consumer test is necessary to conclude that. Trends point towards locally produced products, one reason why Swedish wine has great potential, yet the future needs to be secured through job opportunities and education. Creating an approval system for Swedish wine is suggested as a future improvement, it is a common procedure in most wine regions.

Klimatförändringars påverkan på kulturmiljöer i Uppsala stad ur ett geovetenskapligt perspektiv

Cultural heritages are environments created by humans that are considered to have a conservation value for the posterity. They can be seen as one of society's non renewable resources. It is important to have knowledge of how cultural heritages are affected by future climate changes.The water flow in Uppsala is estimated to increase during winter and decrease during spring and summer. Precipitation will gradually increase as well as the intense short period precipitation. The average temperature is estimated to increase as well.

Glowtest Fixture

The project, Glowtest Fixture, has been carried out to and in collaboration with MSA SordinLtd. MSA Sordin Ltd produces and sells ear protector and is at present a supplier on theworld market. Glowtest Fixture is a product for glow testing off detailed components in oneear protector. MSA Sordin Ltd sends today away your products for testing what is anexpensive aspect in their development. The project's aim is to take forward a test equipmentthat copes with those high nonplussed requirements and wishes that are required for anapproved physical execution.Glowtest Fixture is a physical equipment that comes used stem glow physical off all detailedcomponents in one ear protector.

Nerver i karpala flexorretinaklet på häst

The anatomy and physiology of reptiles and mammals are in many ways different, and will therefore possibly complicate anesthetic administration. Lizards are ectothermic and one should keep in mind that a decrease in the lizard?s environmental temperature may result in reductions in anesthetic metabolism. Respiratory depression is a profound problem because lizards lack a diaphragm, making inhalation and expiration completely active processes. This, in combination with cardiac shunting and breath holding makes the effects of anesthesia unpredictable.

Anestesi av det neonatala fölet

Every spring you can see newborn foals running on fields among the mare. But some unfortunate end up visiting the equine hospital requiring surgery. This is a challenge for the anesthetist because of the neonatal foal?s unique physiology. Therefore you need to take these differences under consideration when you anesthetize foals.

Barley starch, structure and properties

Starch is a naturally occurring substance in most plants and is used as energy storage. It is a component that mainly consists of amylose and amylopectin. Together they build a complex pattern which gives starch its specific properties. The proportion of amylose and amylopectin varies in different plants but generally starch consists of 25 % amylose and 75 % amylopectin. There have been discoveries of barley varieties containing 100 % amylopectin called ?waxy starches? or ?waxy barley? as well as varieties that have a high content of amylose, around 70 % and these are called ?amylotypes?.

Kalciums och magnesiums inverkan på arsenikavdrivningen i virvelbäddsugnen : The influence of calcium and magnesium on the expellation of arsenic in the fluidized bed furnace

In the fluidized bed furnace at Rönnskärsverken, Skelleftehamn, sulphur-containing ore concentrates are roasted in order to remove about 50% of the sulphur in the incoming ore concentrate. This occurs in order to reach the goal of a matte containing 55% of copper in the following smelting process. At the same time as the ore concentrate is partially roasted pollutions as arsenic, antimony and bismuth are expelled. Earlier made thermodynamic calculations of equilibrium suggested that calcium and magnesium form stable compounds with arsenic and thereby inhibit expellation of arsenic in the fluidized bed furnace, an element that is undesired. The purpose of this thesis work was to gain knowledge of the mechanisms behind the formation of these stable arsenic compounds.

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