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4952 Uppsatser om High temperature electronics - Sida 49 av 331

Rostfärgat slam i dränagesystem vid vattenkraftsanläggningar : orsaker och åtgärder

From embankment dams is something that has long been noticed and given rise to different questions. The most serious question is if the sludge is a result of inner erosion through the dam, and thus consists of material transported from the dam. Concerns have also been raised whether the sludge could interfere with the systems drainage capacity and thereby lead to high pore pressure in the dam, or if the measurement of seepage is disturbed, as the measuring is usually made via Thomson weirs, which could risk being blocked. The result of this investigation shows that the sludge is a result of the oxidation of iron by iron bacteria, and to the greater part consists of these oxides as well as the bacteria?s own structures. The iron oxidizing bacteria, FeOB, oxides ferrous iron to ferric as a part of their metabolism, and thereby create large quantities of iron(oxy)hydroxides.

Blir ko och kalv mindre stressade vid ko-kalvseparation med nos- och slickkontakt än när de bara kan höra varandra?

The aim for this study was to investigate if it is less stressful for cow and calves in loose housing systems when separation is made so they can see and touch each other (Physical Contact-PC) instead of just hearing each other (Hearing Contact-HC). The behavior of eight cow- calf pairs (n=4 pairs per treatment) on an ecological dairy farm with cubicle housing were studied for four hours directly after separation and four hours the day after separation. The first four cows that gave birth were used for treatment PC, and the following four cows that gave birth were used for treatment HC. The only selection criteria used was that both cow and calf were healthy. Separation took place 3-4 days after birth and the calves were put separately in two different pens while the mothers were let loose into the cubicle system.

Luft/luftvärmepump : - Med möjlighet till återvinning

Sweden has long had access to low electricity prices due to the wide availability of hydro and nuclear power. This has now changed because of today's rising electricity rates resulting in increasing heating costs for properties, especially in the properties with electric heating systems."Ankaret" is a parish for "Svenska Alliansmissionen", which is located at "Gullbrannagården".The parish has installed electrical radiators and an exhaust ventilation system that makes the energy demand high due to the large ventilation flows. The building was built as the price of electricity was still low and would reduce energy use today by combining its heating system with an air/air heat pump. The heat pump delivers more heat into the room than the electrical energy that it uses. This lowers the electricity needs.

Kassaflödesanalyser - En undersökning av kassaflödesanalysens användning i förhållande till det tidsperspektiv som styr företagens agerande.

Purpose: The purpose of this thesis is to investigate potential associations between usage of the cash flow statement report and time perspective in which companies? acts and set goals. Method: Our approach is quantitative, using empirical data summarized in a statistical procedure. The result is thereafter analysed through the developed analysis model from which conclusion is drawn. Results: We have in the investigation stated that the usage of the cash flow statement report varies depending on the time perspective in which companies? acts.

Skolan har fatta', det nya är surfplatta! : Implementation av surfplattor i grundskolan.

During the last two decades, technology has developed rapidly. It has become a natural part of everyday life, which we today take for granted. It isn?t until the last few years that technology has quickly become a big part in the school environments. Computers, tablets and other technology is today a big part of the education and teaching.

Evaluation of an ectomycorrhizal macrofungi as an indicator species of high conservation value pine-heath forests in northern Sweden

Since the 1950s, the development of modern rotation forestry in boreal Fennoscandia has resulted in a severe reduction of older forests, and a high degree of fragmentation among the small patches that remains of old forest. In Sweden, when performing conservation value assessments in order to identify and preserve the remaining forest habitats, the government authorities use to a significant extent a set of indicator species that indicate habitats of high biological conservation value. One species considered to indicate high conservation values in pine-heath forests is the red-listed ectomycorrhizal (EM) macrofungi Sarcodon scabrosus (Fr.) P. Karst. In the present study, the validity of using S.

Kvalitetsledningssystem enligt ISO 9001 : Produktionsprocessen

This report is the result of a thesis work done at the Department of Engineering Sciences, Uppsala University, and includes 15 ECTS points. The work has been performed at Företag A, a company specializing in electronics whose major product has become a sophisticated tool used by authorities across northern Europe. Företag A has initiated a quality management system according to the criteria set by ISO 9001. Following demands from customers, Company A has now decided to also start working towards a certification according to SS-EN ISO 9001:2008, this work is the foundation for the thesis work. The thesis work has been limited to the production process and the aim has been to enable this process to be certified according to ISO 9001:2008. The work has been performed by analyzing the existing quality management system and the requirements for each process included, whereby the gap between the current and the target state has been mapped. Suggestions have then been made on how this gap can be filled, some of these suggestions have also been carried out during the thesis work. The conclusions drawn are that quality management does not have to be complicated, but quickly becomes so when the complexity of the processes increases.

Åsktransienter och överspänningar : En spänningsfylld simulering av elkraftsystemet vid Forsmark 3

A power system will inevitably be subjected to transient overvoltages, most often produced by switching operations and lightning strikes. These transient overvoltages may harm sensitive equipment without sufficient protection, but it is not an easy task to predict what transients may occur or how they affect the system. A fault occurred in a low voltage system at Forsmark 2012 and overvoltages from lightning were concluded as the probable cause. The three aims with this thesis are to develop and test a model of the power system at Forsmark 3, analyse the transient behaviour of the system when subjected to lightning surges and identify critical parameters, and lastly to provide a tool for investigating the protection of the system. The modelling and simulations were performed in the freely available simulation program LT Spice.

Optimism och stress : En enkätundersökning om förhållandet mellan självupplevd optimism och stress

The idea with this study is to examine if there are a connection between how optimistic people are in relation to how stressed they feel. The result from the survey is based on materials from a questionnaire has been sent to fifty persons of varying age and sexes. The questionnaire has also been sent to students from Karlstad University but also to friends and acquaintances. The data is measured with SE- and LOT-tests. The issues concerned in which scope respondents experiences themselves stressed and optimistic and how the connection is between experienced stress and optimism in relation to results on the figure tests.

Driva tulpaner i näringslösning eller i jord :

The aim with this thesis is to make a comparison between forcing tulips in a hydroponic system and the forcing off tulips that have been planted in soil. The results are mostly based on interviews with six Dutch and one Swedish tulip forcer and the managing director at the Horticultural Research Centre, Proeftuin Zwaagdijke, in the Netherlands. There are benefits and disadvantages with both methods. Tulip bulbs planted in soil seem to get a brighter colour after forcing, compared with those forced ?in water?.

Spolmaskangrepp är ett ökande problem hos värphöns

This literature review summarizes available data on infection with the parasitic roundworm, Ascaridia galli, as a cause of disease in poultry, including the consequences of a conversion to alternative production systems. Ascaridia galli has a direct life cycle with resistant eggs that survive and are easily spread in the environment, especially in systems with bedding materials where the faecal contact is high. The infection is usually subclinical but depending on the infection dose, the symptoms range from weight loss and diarrhea to mortality. Factors such as the feed composition and genetic variation among different hybrids clearly affect the establishment rate of the infection. Ascaridia galli will probably become an increasing problem, with a shift from the traditional battery cages to alternative systems where the risk of re-infection is high.

Varför handla svenskt kött? : en konsumentundersökning

The background to the work bases on the consumers view around Swedish and foreign meat products, and how the attitude around the meat products is pursued in the shops. The consumers request high meat quality and security . Many consumers value local produced and ecological meat products but the price is too high. We have done verbal interviews with consumers on three different shops, where we asked questions and had dialogues around Swedish meat products where the consumers have told us their arguments and opinions about Swedish and foreign meat. The result shows that the majority of consumers consider that it is important to know that meat is produce in Sweden.

Storage stability in a milk based UHT-beverage : effect of pH, carrageenan and storage time

The different characteristics of many food products, such as aroma and texture, changes during storage time and become undesirable. The reason is instabilities within the product which become prominent as the product ages. These changes in characteristics are quality losses caused by changes in the product?s intrinsic and extrinsic environment. The stability in UHT-milk and beverages similar to it have been studied in the past decades and a certain focus have been on age gelation which is a common defect in these type of products.

Biosensorsystem fo?r o?vervakning av vattenkvalitet

Sweden's drinking water quality is considered to be high partly due to a high quality of the raw water and a well developed sewage infrastructure. Despite this, there is water contamination that could be prevented by installation of a sophisticated early warning system. Some of the major players in the production of drinking water have already invested in different types of early warning systems to ensure drinking water of high quality. There are various forms of early warning systems where automatic monitoring of E. Coli is an interesting alternative.

Folkhälsa och välfärd - En litteraturbaserad studie om hälsans betydelse för ekonomisk tillväxt

The interest in the significance of public health for economic growth has increasedsteadily in recent years and a clarification of this connection may be of importance forthe status of public health. Aim: The aim of this literature based study is to describewhat previous research has shown in terms of the connection between public health andeconomic growth, focusing on high-income countries. Method: The study is based ontwelve scholarly articles retrieved from four scholarly databases. Result: The resultclarify that there is a positive long-term correlation between good public health andeconomic growth in high-income countries. Good health has a positive effect onproductivity, which leads to increased economic growth.

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