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714 Uppsatser om Skin temperature - Sida 2 av 48

Test och verifiering av en ny inkapslingsmetod för SiC BJT och MOSFET

The use of silicon carbide (SiC) as a base material in power electronics has manyadvantages, including high breakdown voltage and excellent temperature endurance.However, the packaging of such electronics presents major challenges and there is aneed for packaging that can operate in higher temperature. The purpose of this thesishas been to develop a test method and verify the functionality of SiC powertransistors prototypes with a new packaging technique developed by Swerea IVF AB.It includes setting up an electrical test-bed for power and high temperature cyclingand analysis of the results. Even though test confirmed functionality after thepackaging process, (at room temperature) the performance seemed to have been reduced. This could be a result of the measurement setup and the packaging process.In higher temperature the transistors failed to operate longer than a couple ofminutes which showed the weaknesses in the design and the challenges with this typeof packaging..

Smittsamma hudsjukdomar hos hund :

This student report is about canine infectious skin diseases. It is primarily directed at veterinary assistans. The report includes a description of the skin?s structure and immunologic defences. The four types of allergic reactions are described. Different diagnostic techniques are also accounted for. The skin diseases included in the report are: fleas, lice, Sarcoptes scabiei, ringworm, Cheyletiella and leishmaniosis.

Skadliga nollflödespunkter i Fortum Värmes fjärrvärmenät i Stockholm : En analys av dess förekomst och effekter

When several production units provide a district heating network, water is pumped from different directions. When the flows from the plants finally meet in the network, the water can be completely still. These places are called zero flow zones. In district heating networks with several plants, which also have different supply temperatures, large and frequent temperature fluctuations can occur when the zero flow zones move. This may cause wear on the pipes, a phenomenon called low cycle fatigue.For this reason it is important to examine where and when zero flow zones that cause temperature changes occur.

Värmestyrning I Handske

This rapport is result of a project. The purpose of which was to design a circuit that is used in a heat glove. The heat glove is the technical aid which provides heat inside a glove.It is specially suited for old people who have problems with cold hands because of decreased blood circulation.There already was an old circuit in the glove that gives a constant current which develops heat from battery to glove through a circuit. The temperature is between 32 and 34 degrees.The problem with the existing circuit was to regulate the temperature. There is only on/off switch and there is no way to adjust desirable value of the temperature.In order to solve the problem the old circuit was investigated.

Healthier vegetables through temperature stress? : a review of Brassica oleracea

The objective of this report is to present a review of the studies which has been carried out up to days date concerning how temperature affects vegetables physiologically when it comes to their health inducing as well as quality reducing features. The essay therefore starts off with defining what is meant by the terms health promoting and quality reducing features. It then moves on to describe how different subspecies of Brassica oleracea, that is to say vegetables such as broccoli, cauliflower, Brussels sprouts and kale, is affected by temperature. B. oleracea was chosen because the species contains several commercially interesting subspecies and therefore provides a broad field even though only one species is assessed.

Temperature monitoring during transport of test samples

Quality is the main focus in management of all laboratories. Accurate results of the analyses are not only determined by the analytical procedure but also by preanalytical factors. In the total analytical process of clinical specimens, there are many possible preanalytical sources of error. Monetoring of temperature on test samples of the transport boxes is one way to reduce the mistakes in the preanalytical phase.In this study, four laboratories from primary health care were invited to participate. The temperature has been measured on test samples of the transport boxes being delivered to the laboratory.In three cases the temperature remained within the limits, but in the fourth case the temperature varied more than the allowed interval.

Spenarnas kondition i automatiska mjölkningssystem : en studie av två spensprayer

Two post milkning teat dips (PMTD´s) were compared in an automatic milking system at Kungsängen Research Farm, owned by SLU (Swedish University of Agriculture) in Uppsala. In the experiment an evaluation system was used where teat condition regarding skin and teat ends was graded according to a scale where 1 was the best score and 5 the worst. The evaluation period was almost six months in total devided into four minor experimental periods. The technician scoring the teats did not know which PMTD that was currently used. Statistical analysis showed a significant difference between the two PMTD´s regarding teat skin condition, but not regarding teat ends.

Potatislagring :

The aim with the thesis is to get deeper knowledge in one of the subjects botany, livestock technology or economy. I have chosen to get deeper knowledge in how to store potatoes. How are you going to act to keep the quality on the potato during the storage, with a minimum of weight lost? My aim with this thesis is to get a view over how the potato act in storage space. The storage environment is very important in the storage space.

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.

Sänkt returtemperatur : Potentiell besparing i fjärrvärmesystem

Optimizing energy systems is, in Sweden, as in many other countries, of growing interest. District heating systems are no exception. In 2012, 285 out of 290 municipals in Sweden had district heating in use and the majority of these systems have a higher return temperature than that which is possible with an error-free substation of day current technology. To, when possible, lower the return temperature is a way of increasing the effectiveness of the district heating system.This study means to investigate, through simulations and calculations, how big of a reduction in production cost a lower temperature in the city of Ystad?s district heating system would correspond to.

Kartläggning av material flödesflaskhals i ICA butik.

In the spring of 2014 Sweco Systems AB were commissioned to design a ventilation system for a newly built preschool in Linköping. Terms from the client was that it cost efficiency would cope with the energy demands that are placed on the building. The unit chosen was a cross-flow heat exchanger, and this work is to compare it with two other heat exchangers to see if a more energy and cost efficient could have been chosen. The heat exchangers that was chosen for the comparison was a rotating- and a counterflow heat exchanger. Simulations have been made to the different heat exchangers by the manufacturers.

Datormodellering av en värmelagrande betongväggs inverkan på det termiska klimatet i ett växthus

This report describes the building of a computer model that makes it possible to simulate the thermal climate in a greenhouse. The computer model is built on the physical theory of heat exchange that occur in a greenhouse, such as radiation and convective heat exchange. The model also includes the heat storage that is active in a greenhouse.The computer model is used to simulate the thermal climate in a greenhouse under three periods, winter, spring and summer. It also investigates which effect a concrete wall has on the thermal climate in a greenhouse. The purpose of putting a concrete wall in the greenhouse model is to investigate the possibility to store heat during the day and then use this heat when the temperature drops during the night.The result from the simulations shows that a concrete wall levels the big difference in temperature that normally occurs under a day in a greenhouse.

Förbränning av träpellets och pelleterad halm i en 40 kW rosterreaktor

The project focus on combustion of softwood pellets and pellets in a 40 kW grate fire reactor at TEC-Lab. Dept Applied Physics and Electronics at Umeå University. Experiments were performed at four primary airs to fuel ratios (0.7 to 1.3), where aspects such as temperature profile, levels of gases (CO and NO), sintering-/-slagging and unburned fraction of the ashes were studied. Four different fuel loads were used for wood pellets (10, 20 and 30 kW) and one fuel load for straw (10 kW). Combustion of straw proved very difficult to ignite, and also led to other combustion-related technical problem such as slag formation due to the relatively low melting temperature-/-slag temperature of the straw.

Ett flervariabelt feldetekteringssystem för övervakning av bärlagertemperaturen i vattenkraftturbiner

The purpose of this thesis work was to develop an automatic fault detection system for surveillance of bearing temperature in hydropower turbines. The parameters used except the bearing temperature were cooling water temperature and cooling water flow. A simple static model based on data sampled every minute was developed to estimate the bearing temperature. Then a detector for detection of change in bearing temperature based on the CUSUM-algorithm was designed. Since the amount of data was very small the developed model was too uncertain to be used in a working system.The designed fault detection system showed to work well for the available data.

Hypotermi vid anestesi av hund

The reasons for hypothermia during general anaesthesia are many and varied. The lowered body temperature causes negative physiological effects and leads to discomfort for the animal during the recovery period. This student report is a combination of field study and literature review. In the field study the changes in ambient temperature and the rectal temperature of dogs were monitored during general anaesthesia. The purpose of the study was to see if the body temperature of dogs was reduced during general anaesthesia.

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