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371 Uppsatser om Solar cells - Sida 24 av 25

Aktiv lastbilsstol för bättre förarergonomi och hälsa

The project concerns a predevelopment work for Scania AB, a leading manufacturer of heavytrucks, and was performed as a master thesis work for the program Design and ProductDevelopment at KTH. The purpose of this work was to examine how the work situation of truckdrivers, especially long-haulage drivers, can be improved with respect to prolonged sedentaryoccupation. Mental fatigue and under-stimulation due to low cognitive load during long drivescan be major risk factors for traffic accidents. Physical strain injuries to both the skeleton andmuscles are common for this working group and minimal opportunity for daily exercise alsoincreases the risk of developing blood clots in the legs, which can have serious consequences forthe driver's health.An extensive background study, both theoretical and exploratory, was performed to identify thedrivers' concerns and comfort needs. Various treatments such as massage and active sitting wereinvestigated and existing products within the area studied.

Mätning av partikelmassa i avgaser från en dieselmotor

This master thesis was a continuation of a previous study in the diesel exhaust characterization, which is part of the academical work embedded in the EMIR-1 project. The main objective of this thesis work was to finish the installation and make the proper modifications of the particulate mass measuring system located in one of the engine test cells at KTH, in order to be able to measure the mass of the particles from the exhaust of diesel engines.This experiment requires a diluted flow sample from the exhaust that should be sent to the device that makes possible the measurement of particle mass, called TEOM. In the first stage of this project, the objective was to study and make the proper modifications in the existing KTH diluter because there were several problems to obtain a constant dilution ratio from it during tests.This modifications were made and it resulted in a great improvement in the maximum inlet and outlet flow that this diluter can handle. Therefore another modification is proposed for controlling the inlet exhaust flow so it will be possible to regulate the dilution ratio and make it constant along a wide range of engine loads and speeds.The second and most important stage was to make particulate mass measurements possible by analyzing the frequency signal from the TEOM device. The idea was to obtain the frequency of oscillation from the tapered element in the TEOM, and therefore with the proper correlations, be able to predict the particulate mass concentration in the exhaust flow from the engine.An electrical problem in the TEOM circuit was detected and corrected, so the signal that carries the frequency from the TEOM can be analyzed properly.

Canine S- and M/L- cone electroretinograms

Full-field flash electroretinography is an electrodiagnostic method used to examine the function of retinal cells. Light stimulation of the eye elicits electrical potentials in the retina. By aid of a corneal electrode and a reference electrode close to the back of the eye, the electrical potentials can be recorded and presented as an electroretinogram (ERG). ERGs driven by mainly one type of cones can be used to examine the function of a single cone class. In human beings, studies have shown the cone class sensitive to light of short wavelengths, the S-cones, to be more vulnerable to acquired damage than the other cone classes (Daley et al., 1987; Gouras et al., 1993; Greenstein et al., 1989). Dogs have two cone classes, S-cones, and M/L-cones (most sensitive to medium to long wavelengths).

Det energiproducerande huset

We are heading towards a huge switch of how energy is produced with fossil fuels being replaced by renewable energy sources. It is not difficult to replace the energy you use in the house and there is no need for futuristic technology. There are already many established products on the market such as high efficiency vacuum solar collectors, heat pumps & small wind power stations that can supply the energy being used in a house. The company Sol & Energiteknik SE AB in Huskvarna has many different products which can reduce the need for an outside energy distributor. An average house in Sweden uses 15 000 kWh for heating, 5000 kWh for tap water and 5000 kWh for electricity.

Att gestalta en socialt hållbar begravningsplats

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

Faktorer som påverkar magnesiumabsorptionen i våmmen hos kor

In metabolism Mg plays an important role because it affects many cellular enzymes in the body. The energy metabolism and protein synthesis are dependent on Mg as an enzyme activator, Mg is also involved in the synthesis of RNA and DNA. Absorption of Mg primarily takes place over the ruminal epithelium in ruminants. The main storage of Mg is in the bones but that can only be reached if the cow is in great need of calcium or phosphorus, it's a hormonal regulated process that induces catabolism of bones. Free and available sources of Mg are found in soft tissues and in the extra cellular fluids that includes cerebrospinal fluids and blood.

Water balance and nitrate leaching from arable land in a changed climate : a model study

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

Mastcellens roll vid atopisk dermatit hos hund

SAMMANFATTNINGDenna litteraturstudie har gjorts med syfte att utöka kunskapen om atopisk dermatit hos hund med fokus på mastcellens roll i immunopatogenesen. Atopisk dermatit är en relativt vanlig sjukdom som kan drabba alla hundar oavsett ras; den är oftast livslång och kräver visst arbete för att diagnosticera och behandla med gott resultat. Förutom att det är ett problem hos hundar, finns även ett nära samband med atopiska sjukdomar hos människa, och hundar fungerar som en bra modell för forskning på humansidan.Trots omfattande forskning, vet man fortfarande inte varför sjukdomen uppkommer. Många teorier finns kring den immunologiska bakgrunden, men stora delar är fortfarande okända. Att mastcellen spelar en nyckelroll är dock allmänt vedertaget.

Utvärtes behandling av sarkoider på häst med Aldara eller Xxterra : en jämförande pilotstudie

Sarcoid is the most common tumor in horses all over the world. The sarcoid is a benign, locally invasive, usually fibroblastic proliferative skin neoplasm. Even if the etiology is not completley verified, the epidemiology and clinical behavior suggest a infectious intervention, probably BPV type 1 or type 2. However, it is known that the cause is multifactorial. A genetic prepdispositon has been identified associated to genes within the Major Histocompatibility Complex (MHC), but also to breed, age and perhaps gender.

Utvärtes behandling av sarkoider på häst med Aldara TM eller Xxterra TM : en jämförande pilotstudie

Sarcoid is the most common tumor in horses all over the world. The sarcoid is a benign, locally invasive, usually fibroblastic proliferative skin neoplasm. Even if the etiology is not completley verified, the epidemiology and clinical behavior suggest a infectious intervention, probably BPV type 1 or type 2. However, it is known that the cause is multifactorial. A genetic prepdispositon has been identified associated to genes within the Major Histocompatibility Complex (MHC), but also to breed, age and perhaps gender.

Miljöcertifiering av ett byggnadsminne

Samtidigt som debatten kring jordens klimatförändring är i full gång har intresset för att miljöcertifiera byggnader vuxit oerhört. För fastighetsägare är det en möjlighet att bevisa för sina hyresgäster och köpare att byggnaden är hållbar. Är en byggnad miljöcertifierad har en oberoende part intygat att den uppfyller en nivå av hållbarhet som bestäms utifrån standardiserade kriterier. Fastighetsägaren kan alltså använda certifikatet i marknadsföringssyfte.Den här studien undersökte om en byggnad som är byggnadsminnesförklarad kan miljöcertifieras med Miljöbyggnad. Målet var att hitta kostnadseffektiva lösningar för att uppfylla de miljöcertifieringskriterier som eventuellt inte uppfylls idag.

Analys av designalternativ för snabbare dynamik i kolkraftverk med koldioxidavskiljning

Combustion of fossil fuels is today the dominating source of energy. During combustion,carbon dioxide is formed. The carbon dioxide accumulates in the atmosphere,which raises the global average temperature on earth through the so called greenhouseeffect. The only way to reduce the emissions of carbon dioxide from combustionin a coal fired power plant is through carbon capture and storage (CCS).Post-combustion capture is a technology to separate carbon dioxide from the uegas after the combustion for efficient transport and storage. The steady state operationof coal fired power plants with post combustion capture has already beenthoroughly investigated on a pilot scale, however much work remains to investigatethe plants dynamic operation.

Lågtempererad fjärrvärme i Umeå

People in today?s society are becoming more and more aware of how important it is to use energy as efficiently as possible. This is clearly noticeable by an increase in home produced heat with e.g. solar panels or heat pumps heating systems. These changing customer demands forces district heating technology to be redesigned, which is why there is an ongoing research regarding the next generation of district heating - low temperature district heating (LTDH).

Genetisk och immunologisk bakgrund till atopisk dermatit hos hund

Atopisk dermatit är en sjukdom som drabbar ungefär en tiondel av världens hundar. Sjukdomen ger som följd av allergenexponering symptom såsom klåda, hudlesioner och otitis externa. Patogenesen för atopisk dermatit är komplex och multifaktoriell. Målet med denna litteraturstudie var att undersöka hur genetiska och immunologiska faktorer bidrar till sjukdomens patogenes. En obalans i T-hjälpar-(Th)-svaret vid atopisk dermatit är allmänt accepterad.

Primärenergianvändning av passivhus i Sverige : Med fokus på Kvarteret Trettondagen

The building sector accounted for around a fourth of the total energy usage in Sweden in year 2010 (Energimyndigheten, 2012). Therefore it has become very interesting to achieve a lower energy usage in residential buildings. One way to achieve that is to build so called passive houses. By being very well insulated and have low leakage through the walls, they can reduce the energy usage for heating with a substantial amount. The first passive house was built during the 90?s in Germany; and in Sweden the first passive house was built in Gothenburg 2001.

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