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4906 Uppsatser om High-frequency - Sida 21 av 328
The effect of social rank on milking and feeding behaviour in automatic milking system for dairy cows
Today automatic milking systems (AMS) are growing in popularity. In these systems the cows are loose and have to get to the robot and the feed on their own. The cows ranking in this system affect their welfare. In this study data from seven years in an AMS was used and analysed. The aim was to investigate how ranking could affect the behaviour of the cows at milking and at feeding.
Kan probiotika förebygga atopiskt eksem hos högriskbarn?
Sahlgrenska Academy at University of Gothenburg Department of Internal Medicine and Clinical NutritionAbstractTitle: Can probiotics prevent atopic dermatitis in children with high risk?Author: Laura Pienihäkkinen and Max OlinSupervisor: Heléne Bertéus ForslundExaminer: Anna WinkvistProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 22, 2012Background Allergic disease is today common, this including atopic dermatitis, which is the most common inflammatory skin disease in the world. Heredity has been shown to play a major role in the development of this disease. It is therefore of high interest for both the individual and society to find effective methods for preventing atopic dermatitis in individuals with high risk profile. Probiotics are beneficial for the bacterial profile in the intestine and it is therefore of interest to study if they through their anti-inflammatory effect could prevent atopic dermatitis.Objective The aim was to study whether administration of probiotics to the mother and the child (directly or via breast milk) could prevent atopic dermatitis in children with high risk profile (at least one first degree relative with a diagnosed allergic disease).Search strategy A systematic literature search was done in databases PubMed and Scopus with search terms maternal, prenatal, probiotics, allergy, atopic dermatitis, prevention, and children.Selection criteria Randomized, controlled human studies and original articles in English were included.
Hur påverkar New Public Management en organisations effektivitet?: En fallstudie av Stockholms Stads Parkerings AB och Stockholms Trafikkontor
This thesis investigates how the level of implementation of New Public Management affects an organization?s efficiency. According to theory, a high level of implementation leads to a more efficient organization. This thesis is based on two case studies conducted on two units within Stockholms Stad. One of the units shows a high level of implementation of NPM and a high level of efficiency.
Träbroar för järnvägstrafik
This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.
Gymnasieskolan som demokratisk arena? En utvärderingsstudie av demokratimålen i Lpf 94
The essay is an evaluative study of student democracy in the Swedish high school, its departure point being the 1994 national curriculum for the voluntary school forms (Lpf 94). We adopted an interview method, the survey units consisting in a number of high school teachers. The analysis has two principal theoretical departure points, involving democracy theory and implementation analysis, respectively. The former is utilized to help identifying what sort of democracy permeates the governing document and high school daily life, the latter to explain actual outcomes.The study concludes that the 94 curriculum is characterized by a strong democracy with emphasis on participatory democratic processes, whereas in practice there is a thin democracy in both classroom and formal student government contexts. Representative processes are given plenty of room although few attempts at participatory democratic components can be identified.A deeper analysis of the result reveals implementation problems traceable to elements of symbolism in the goals.
Komfortsanalys med hänsyn till vibrationer orsakade av människoaktiviteter. : Ett modernt dimensioneringsproblem för huskonstruktörer
Comfort analyses regarding human induced vibrationsIt is not too common among civil engineers in Sweden to perform comfort analyses considering the vibrations caused by human activities. In addition, the Swedish standards lack requirements to be used for comfort analyses in design of floor-systems. The demand for large spans in combination with slender slabs, is today a reason to investigate the floor-system constructions, in order to prevent disturbing vibrations and oscillations.The purpose of this thesis is to create a guide for how a comfort analysis, considering vibrations, should be implemented. Göran Svedenbjörk who is an expert in structural dynamics has been interviewed where he presents his latest project Värtaterminalen and answers some questions about vibrations due to human activities.Floor-systems, consisting of concrete slabs supported by steel or concrete beams, have been investigated with simulations in the finite element program Abaqus. In the simulations, the influence of various factors on the natural frequency of floor-systems and the acceleration level caused by dynamic loads, is studied.
Frekvensomriktare i hydraulhissdrift
Hydroware Elevation Technology AB sells control and regulation equipment for hydraulic elevators. The company now wants to investigate the possibility of changing their present softstarters to frequency inverters to supply power to their pump engines. They also want to investigate the possibility of future use in so called ?intelligent? houses.The purpose of this report is to investigate these possibilities..
Kommunikationseffektivitet och kommunikationsstrategier för L1- och L2-talare i referentiella problemlösningsuppgifter
This thesis examines and measures differences in effciency between L1- and L2 language use for solving referential problems. Quantitative measures used in the study were time and error frequency. Qualitative measures, such as how the tasks and the participants own performance were experienced, were measured by an post interview and two questionaires. Two different tasks, a sorting task and a construction task, in which each informant was given the role as a constructor or instructor, were used for data gathering. A total of 20 dyads, divided in two language groups (English and Swedish) participated in the study.
Hälsa och datorkonsumtion bland pojkar i årskurs nio : En komparativ tvärsnittsstudie
The aim of this study is to investigate the prevalence of computer consumption among boys in ninth grade, and to see if there were any differences with regards to physical activity, sleeping habits, breakfast habits and BMI. The study has cross sectional design with a comparative and a quantitative structure and is based on a former study called ?Food & Health 2007?. The respondents were represented by 181 boys in ninth grade, recruited from ten different schools in the county of Uppsala, who were answering questions about media consumption, breakfast habits, physical activity and sleeping habits. Daily computer consumption was reported up to one hour for 12 % of the respondents, one to three hours for 65 % and over three hours for 42 %. The boys who had a high physical activity level were less frequent in computer consumption while those who had a low physical activity level spent more time by the computer.
Prefabricerade ramper i stålfiberbetong
This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.
Undersökning av vissa beläggningars påverkan på antenners effektivitet i tågmiljö
For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.
Aktiv förvaltning : en utvärdering under volatil tid
Over a long period of time, there has been a rich debate in the academic and financial world if active management can generate an excess return. Many experts say that the current active management strategies is nothing more than a money grab that produces large gains, for banks and investment firms, through high management fees while producing no excess value for the individuals buying their service. In short, an effective market makes it almost impossible for fund managers to produce value for their clients in the long run.No argument has only one side though, other experts say that active management has a role to play because not all investors are rational. This irrationality can lead to mispricing on financial assets in the marketplace and in turn lead to an ineffective market where active management can fill a much needed role. The purpose of this study is therefore to see if active management strategies can create a higher risk adjusted return, taking management fees into consideration, during times of high volatility when the uncertainty is at its peak.
Stålfiberarmerad betong - En ekonomisk jämförelse
This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.
Att övervinna barriärer för kunskapsåterföring - En fallstudie av NCC
This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.
Utveckling av en metod för avvikelsehantering i byggföretag
This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.