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574 Uppsatser om Temperature gradient - Sida 17 av 39

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The consumer society exploits the earth?s resources more than the earth itself has capability to produce. This over-consumption causes a mass production of products, which mean that more greenhouse gases are being emitted to the atmosphere. This is one of the reasons why the earth?s temperature is rising, where the result of it is worldwide disasters.

Närklimat vid avvänjning av smågrisar :

SUMMARY Several studies have shown that weaning pigs are in great need of heat. The reason for this is mainly because the pigs are given very little feed just after weaning. Some of the pig producers of today have tried to get along with these problems by building some kind of hut for the pigs. Some of these pig houses have been included in this study.The study has shown shortcoming functions for the pig cottage. The expected heat increase has not occurred.

Inneklimatet på ett kontor : Undersökning av inneklimatet vån. G4 stadshuset samt kontor på Ånghammargatan

This report describes an investigation of the indoor climate in two different workspaces. Since we a big part of our lives are staying indoors in artificial environments, and more particularly in our workplaces, we think it would be interesting to do this investigation. The technical solutions for air treatment systems began with simple natural systems without fans and where the thermal rise of the air applied. In modern time is technical air treating systems used to take care of the fresh air supply. This type of units can supply filtered air with the right temperature to the building. Well-functioning ventilation is essential to bring clean fresh air to the room and effectively remove impurities without sound- or draught problems. The indoor climate is relevant for the output capacity.

Deaktivering av metanisering katalysatorer

A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.

Utvärdering av VAV i nybyggt kontorshus

VAV (Variable Air Volume) system has been studied in a newly constructed office-building. The goal for the study has been to evaluate how the ventilations system work in practice, if adjustments can be made to achieve an more energy efficient system and to evaluate if other alternative ventilation systems is to be preferred in the further.The degree project has been executed at Helenius Engineering Firm who is working with the environment, media systems, HVAC and energy in buildings. The building that has been studied is owned and operated by Akademiska hus.Literature studies, visits at site, inventory, review of system documentation, energy analyses, interviews, key figures, LCC, sand energy- and indoor climate simulations has been made to study the building. Where appropriate some tools from Six Sigma have also been used.How to achieve an energy efficient system and a pleasant indoor climate is studied with human health and well-being as base for the indoor climate requirements. Technical support systems such as ventilation systems have to be designed so that an acceptable indoor climate can be achieved.

Hur påverkas bentiska funktionella födogrupper av kalavverkning? : Effekt på abundans, samt återhämning, av funktionella födogrupper efter kalavverkning kring små vattendrag.

Forestry affects most of the forest-covered land in Sweden. In the landscape, the most common stream type is headwaters, which are important sites for many processes and organisms in both the terrestrial and the aquatic ecosystems. The aim of this study was to investigate how the abundance of benthic invertebrate functional feeding groups in headwater streams develops after clear-cutting and if it also is possible to detect a change in the composition of feeding groups. The study also attempts to determine what factors have an effect on temporal changes in abundance of these groups. For the study, 11 sites in northern Sweden were sampled for benthic invertebrates using a Surber-sampler, and for each site canopy-cover and pH was obtained.

Mean value modelling of a poppet valve EGR-system

Because of new emission and on board diagnostics legislations, heavy truck manufacturers are facing new challenges when it comes to improving the engines and the control software. Accurate and real time executable engine models are essential in this work. One successful way of lowering the NOx emissions is to use Exhaust Gas Recirculation (EGR). The objective of this thesis is to create a mean value model for Scania's next generation EGR system consisting of a poppet valve and a two stage cooler. The model will be used to extend an existing mean value engine model.

Hur ackommodativ facilitetsträningpåverkar ackommodation, vergens och binokulärseende

Syfte: Syftet var att undersöka om och i så fall hur ackommodativ facilitetsträning, med +/- 2,00DS-flippers, under en vecka, påverkar ackommodation, vergens och binokulärseende.Metod: I studien undersöktes 17 försökspersoner mellan 20-30år. Av dessa fick 3 försökspersoner avbryta medverkan på grund av olika skäl. Försökspersonerna ombeddes att sitta på 2 synundersökningar, varav en före och en efter ackommodativ facilitetsträning. Undersökningarna inleddes med ett objektivt refraktionsvärde, följt av en anamnes. Därefter utfördes en binokulär synundersökning tillsammans med binokulära mätningar, varav en mätte den ackommodativa faciliteten.

Klimat i djurtransportbil med slaktgrisar sommartid : jämförelse mellan naturlig och mekanisk ventilation

SAMMANFATTNING Uppskattningsvis transporteras 171 miljoner grisar inom EU varje år, varav ca 3,5 miljoner i Sverige. Grisarna kommer, under hela förloppet från förflyttningen från box i stallet till bedövningen i slakteriet, att utsättas för stressande moment. Orsakerna är bland annat omgrupperingar, nya miljöer, vibrationer i bilen samt, speciellt under sommaren, värmestress. Temperaturen i djurtransportbilen är en nyckelfaktor som dessutom kan förstärka effekten av andra stressorer. Lastning i höga temperaturer ökar risken för värmestress. Värmestress innebär att djuren får allt svårare att avge sin värme. Även den relativa luftfuktigheten har betydelse, framförallt vid temperaturer över 30°C. Det är ventilationen i transportbilen som ska transportera bort värme och fukt från bilen.

Habitatval, migrations- och furageringsaktivitet samt homing hos gädda (Esox lucius) härstammande från Österby myr, Gotland.

In this study the spawning migration activity, habitat choice (depth and temperature), foraging activity, duration of stay in the spawning site and homing-behavior was studied for anadromous pike (Esox lucius) in the wetland Österby myr, Gotland.The spawning migration was concentrated to dusk and dawn, a homing behavior was confirmed and there was no significant difference between sexes with respect to duration of stay. A difference in habitat choice and small variation in foraging activity between individuals was established..

Matting of Natural Image Sequences using Bayesian Statistics

The problem of separating a non-rectangular foreground image from a background image is a classical problem in image processing and analysis, known as matting or keying. A common example is a film frame where an actor is extracted from the background to later be placed on a different background. Compositing of these objects against a new background is one of the most common operations in the creation of visual effects. When the original background is of non-constant color the matting becomes an under determined problem, for which a unique solution cannot be found. This thesis describes a framework for computing mattes from images with backgrounds of non-constant color, using Bayesian statistics.

PTAG - aktiv RFID-tag med GPS

Free2Move AB is developing products for the market within wireless communicationand identification, among those active RFID-tags. The company had an idea aboutproviding one of their active RFID tags with a GPS receiver and transmit positions viaan existing RFID protocol. Desire from the company was also the possibility to logpositions and measure temperature. The finished prototype should also be able to beactivated by movement. The company had proposal about components that were to beused in the project.

Klinisk termografi som diagnostiskt hjälpmedel vid rörelsestörning hos häst :

Thermography is the assesment of the surface temperature of the horses body and it falls into the categori of physiological imaging. Thermography allows us to portray inflammation and changes in sympathetic tone in a graphical manner. The purpose of this study was to review thermography in equine medicine and to evaluate thermography as an aid in the diagnosis of lamness in horses. Thermography has been helpful to identyfy sprains, stress fractures, shin splints and soft tissue, tendon, ligamentous and nerv injuries and to monitor healing processes during rehabilitation. Routine thermography may reveal inflammatory responses prior to clinical signs. In present study thermograpy gave especially valuabel information in two cases. In one horse reduced blood flow in a. saphena due to a thrombosis were visualised and in the other horse bilateral thoracolumbal radiculopati was diagnosed.

Perianestetisk omvårdnad av häst :

This work is a combination of a literature study and a practical pilotstudy. In the literature study essential physiological reasons of why anaesthesia of horses is so risky are explained. Diffrent methods of induction and recovery are brought up, together with significant aspects of positioning the horse on the operating table and perianaesthetic complications such as myopathy, neuropathy and limb fractures. The pilotstudy had the purpose of examine the bodytemperature of horses undergoing general anaesthesia and to control the perianaesthetic temperature measurements performed in Swedish horseclinics and veterinary hospitals. Our hypothesis was that the bodytemperature of the horses would decrease but not enough to cause a problem. The purpose of this work has been to gather more profound knowledges in the subject of perianaesthetic nursing of horses which is an important part of the assignment of a veterinary nurse..

Brännkammare för träpulver : Teoretisk analys och praktisk försök

The thesis describes a completely new biofuel system to generate particle-free heat from combustion of ash-containing biofuel particles at high temperatures.The suggested system gives opportunities to introduce biofuels in new areas.Main components in the suggested system is a heat radiating combustion chamber intended for pulverized wood, combined with regenerators to extract heat from flue gases and simultaneously preheating the combustion air.The thesis contains a description of the suggested system, theoretical considerations, calculations regarding the combustion, and includes results from tests performed.The results from calculations and tests performed concludes that the system is workable and possible to apply..

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