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4952 Uppsatser om High temperature electronics - Sida 9 av 331

Produktion av Pyrolysolja från kvistrejekt

Fast pyrolysis is a method for converting biomass into three energy rich products: char, gas and bio-oil, where the latter is most interesting.  Pyrolysis is an endothermic process where biomass is heated in an anaerobic environment and, with the right operating conditions, up to 80 %wt bio-oil can be extracted. Key parameters for fast pyrolysis are: stable reactor temperature (~500°C), short residue time for gas in the reactor (<2 s) and a very high heating rate for the biomass. Today there are several different process solutions for fast pyrolysis, where fluidized beds and rotating cones are most developed. Bio-oil has compared to fossil oil: lower heating value, low pH and also polymerizes with time. Because of this upgrading is desirable for increasing competitiveness.

Skalning och brusberäkning av tvåportsadaptorer

The goal of this work is to summarize the calculations for scaling and noise of twoportadaptor. Two different methods has been described and used for the final results..

Problem med röda hamburgare efter tillagning : bakgrund och möjliga lösningar

Persistent pink in beef patties and hamburgers is a problem in the meat industry that has been known for a few decades. It is a costly problem as it can give rejections of food by consumers. Studies around the world have tried to solve the problem but it still remains a mystery. There are many different theories of what is causing the red colour. Some of the most likly theories are reducing hemocromes, high microbiological loads, contamination of nitrite or organic/non organic substanses, DFD meat etc.

Comparison of stable environment in prior approved and non-prior approved horse stables

To establish good horse welfare there are several factors that need to be considered. One important factor is the environment in which the horses are kept. In Sweden horses are stabled during long periods of time in the cold season and consequently the stable environment is even more important. The most essential environmental factors in a horse stable are ambient temperature, relative humidity (RH) and concentrations of contaminants in the stable air. The air in a horse stable contains dust, noxious gases, moulds and microorganisms which all can contribute to developing respiratory diseases in horses.

Kalvhyddans utformning : påverkan på kalvens hälsa och komfort

This paper aims to, through a literature review, examine how to best design and adapt calf huts to meet the calf's physiological requirements and reduce the infection pressure for enteric and respiratory diseases. It illuminates how the calf relates to different temperatures and climate, which temperature control mechanisms it uses and its ability to perform these regulations, as well as providing a summary of the past decades´ research on the calf huts housing system. These two theory chapters, along with a concluding discussion, provide a better understanding of how to, especially in temperate climates, design the most suitable calf hut, which cater to the calf's both thermal comfort and physical health. The literature suggests that the calf's own temperature control works well to counteract the temperature outside the desired range, and that one of the most important factors rather is ventilation of a calf hut, which reduces moisture and pathogens. The conclusion of this paper is mainly that there is not an obvious way to place and construct a calf hutch and that most design principles contribute to both positive and negative effects simultaneously.

Energi och klimatanalys O-huset på Campus i Halmstad

AbstractThe indoor environment affects the human performance. Noise pollution, poor lightning and coloring are some of the factors that affect our work performance. The human is also affected by the air change and temperature, these factors are in most buildings possible to adjust and through this make economic savings. To find out about the indoor environment in the O-building a questionnaire was handed out, measurements/surveys and an interview was also made. 108 questionnaires where handed out to employees and students.

Möjligheter att utfodra överskottsmjölk till kalvar efter pastörisering

Good feeding practices are a basic aspect of good calf health. During the calf's first few months the calf is fed with purchased milk replacer or raw milk straight from the cow. On all farms, it will be a surplus of milk that may not be delivered to the dairy for various reasons. Milk that may not be supplied to the dairy includes colostrum and milk with unnormal properties, including milk from cows suffering from mastitis. This study investigated the possibility of improving the milk by pasteurization in order to secure its use as feed for calves and thereby obtain an improved calf health.

Produktutveckling och prestandatest av ett vattenvärmedrivet torkskåp : Jämförelse mellan tre utvecklade versioner av ett vattenvärmedrivet torkskåp

AbstractElectricity consumption is a globally increasing problem caused by the high share of electricity produced in coal power plants. These contribute to high carbon emissions when only about 1/3 of the heat generate electricity and the remaining 2/3 of the heat cools off. Combined heat and power plants (CHP) have high efficiency because they use the residual heat for domestic heating. The CHP plant often use fuels from renewable resources, giving them a lower carbon footprint, but are also depending on the heat demand. If electric powered products such as drying cabinets convert to heat powered products more environmentally friendly electricity will be produced by CHP plants, which can supplant electricity, produced from coal power plants and reduce carbon emissions.

Implementering av Constant Fraction Detection vid avståndsmätning

This thesis is performed at Saab Bofors Dynamics in Karlskoga and investigates a technique for ranging with laser pulses. The investigated technique is called Constant Fraction Detection (CFD). Described briefly, the received laser pulse is split into two equal parts, where one part is delayed half the pulse width and inverted. This signal is added to the original pulse. The resulting curve has the shape of a laying S and the detection of the zero level is used to stop the time measurement.

The shift in forest and tree limits in Troms County - with a main focus on temperature and herbivores

To better understand how various factors affect the establishment of forest and trees around the tree line-ecotone, this study was conducted in Troms County, Norway. The altitude of different forest and tree limits together with the surrounding vegetation type were collected during August 2011. Comparisons of the collected data were made with previously collected data from the same sites conducted 1914 and 1915. On average the forest limit has expanded with 26 meters in altitude, however, an expansion is not statistically significant for the whole area. The tree limit has significantly expanded in altitude.

Mätningar och analys av elnätet hos FHP, Basproduktion

This report is a degree project performed at Freudenberg Household Products AB, (FHP). The degree project comprises measurement and analysis of the power net at FHP Basproduction. The content is divided between one theory-part, one document- part with measurements and also conclusions and a list of measures to be taken. During the project the purpose and restriction change from a quality investigation to only concentrate on harmonics and finding the reason why they exist, and also to find a solution to the problem with harmonics. The measurements shows that the power net contains harmonics of different order and intensity.

Fisk- och fågelpredations påverkan på den bentiska makroevertebratfaunans sammansättning under tidig vår i Tåkern

Predation is one of many factors that form the structure of the macroinvertebrate community in lakes, wetlands and watercourses. Earlier studies lack an examination concerning how fish- and waterfowl predation affect macroinvertebrates during shorter periods in the spring. I performed an exclosure study in the shallow eutrophic Lake Tåkern which is located in the western part of Östergötland County, Sweden. The experiment was performed during a three week period (1-21 April 2012) when the water temperature was low and the density of migrating diving ducks was high. The experimental cages used included three out of four different treatments; general predation (open cages), bird exclusion (net with mesh size 90*45mm) and no predation (net with mesh size 1*1mm).

MEMS baserad referensoscillator

The interest in tiny wireless applications raises the demand for an integrated reference oscillator with the same performance as the macroscopic quartz crystal reference oscillators. The main challenge of the thesis is to prove that it is possible to build a MEMS based oscillator that approaches the accuracy level of existing quartz crystal oscillators. The MEMS resonator samples which Philips provides are measured and an equivalent electrical model is designed for them. This model is used in the simulations of the Pierce oscillator and the transresistance amplifier oscillator that are evaluated in this thesis. Finally the Pierce oscillator is implemented in the A BCD2 process and manufactured at Philips Semiconductors in Nijmegen, The Netherlands.

Energikonsumtion hos en diskmaskin

The dishwasher is a wide spread product that occurs in many households. It saves the user time,water and energy. When using a dishwasher instead of doing dishes by hand a lot of energy issaved.The importance of lowering the energy consumption does not only come from the consumerwinnings but also from an environmental point of view. Scientists are certain that the globalwarming comes from the emission of green house gasses that is created by human consumptionof oil, gas and coal.Dishwashers today are a lot more energy efficient than older dishwashers, but there are stillmargins to lower the energy consumption. The aim with this project is to investigate thedishwasher and it?s washing cycle, noting different phases and components that contribute towaste of energy.

Hundhållning i bil : situationen i Sverige och effekter av utetemperaturen. Enkätundersökning och experimentell studie

The aims of this project were to describe the circumstances around dogs being left alone in cars, to investigate owners? knowledge of the risks associated with leaving dogs in cars and the relevant legislation and, finally, to study how changes in the air temperature and air composition in the car affect the dog. The project consisted of a survey of the literature, a questionnaire part and an experimental part. An important conclusion is the importance of the level of knowledge of owners, since there are several ways in which an owner can prevent their dog from heat stroke and, in the case of an eventual accident, their action can have direct consequences in minimizing the long-term damage to the dog and even whether or not it survives. Fewer than half of the owners in the study knew that for a dog suffering heat stroke, the most important thing is to bring the body temperature down. Only a third of dog owners knew that if a dog is left in a warm car and showing signs of heat stress, then the police should be contacted and the dog quickly helped out of the car.

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