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4906 Uppsatser om High-frequency - Sida 25 av 328

Mjölkkors välbefinnande i AMS och konventionell lösdrift : skillnader i beteende och hormonstatus för oxytosin och kortisol mellan kor av hög och låg social rang

The purpose with this study was to investigate how the behaviour and physiological parameters differ between high ranked and low ranked cows, and between cows in an automatic milking system verses conventional milking parlour. The study was carried out at the Kungsängen research Centre, Department of animal nutrition an management, Swedish University of Agriculture Sciences, Uppsala. Twelve cows, the six highest and the six lowest in social rank were selected from the automatic milking system for the experiment. Ten cows, the five highest and five lowest in social rank were selected from the conventional system. Blood samples were taken during milking and resting.

Hur elever läser - En jämförande studie av gymnasieelevers lässtrategier i biologi och engelska; How students read - A comparative study of high school students? reading strategies in Biology and English

The purpose of this study was to identify reading strategies used by high school students when reading textbooks and school-related material. Any differences in reading strategies between Biology and English were also of importance. A study sample of 62 students from three different high schools in Sweden participated in the study and were asked to fill out a survey questionnaire. Eight students from this sample were also interviewed. The findings of this study show that students use a number of different reading strategies of which metacognitive and sociocultural factors play a crucial part.

Viltbroar i Sverige. En jämförelsestudie på rörbroar av stål som alternativ till traditionella betongbroar vid uppförande av faunapassager

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.

Utredning av Aktiv designprojektet vid RV40. Inriktning mot utveckling av objektiv kontrollmetod med avseende på framtida funktion

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 samband mellan MCV och geotekniska parametrar. Analys utifrån fält- och laboratorieförsök på finkornig jord

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.

Effekter av fysisk aktivitet på psykisk ohälsa hos unga kvinnor

Among young adults and especially women, psychological issues are common phenomena in the society such as depression, anxiety and stress. Research has shown that physical activity can be a complement for anti-depressant medication. The aim of this review is to examine previous research to find out how physical activity can provide positive effects on overall mood state in particular young women's psychological health. The results of this review is that there are support in the literature of young women that physical activity may enhance mood in studies of depression and anxiety symptoms and small support for the effects on reducing stress. Physical activity with both high intensity and low intensity has shown to have positive effects on depression and anxiety, but the physical activity has to be regular for long-term effects.

Skapandet av ett fredligt samhälle. Vad kan vi göra? : En studie av gymnasieelevers uppfattning om skolans och deras egen roll i skapandet av en fredligare värld

The aim of the study is to examine what upper secondary school students think that they themselves and their school can do to create a peaceful society. The study combine qualitative and quantitative methods based on questionnaires distributed among 328 students in three high schools in Sweden. The survey is a combination of multiple choice and open questions. For the analysis of quantitative responses the computer program SPSS was used producing frequency tables and response rate schemes. To analyze the questionnaire's qualitative part a narrative analysis method was used.

Stress, Konformitet, Grupptillhörighet och Självvärde hos flickor i gymnasiet

Abstract- Stress, conformity, groups and self-worth in high-school girlsThe aim of this questionnaire-survey was to investigate the experience of stress and symptomsof stress in high-school girls, and to examine if the experienced symptoms of stress could bepredicted by groups, self-worth and conformity. Another purpose of this study was to describethe girls own thoughts concerning these factors. 80 girls between the ages of 15-18 yearsanswered the questionnaire. The results showed that stress could be predicted by theexperience of conformity, but not by the experience of belonging to a group and self-worth.The most common symptoms of stress were tiredness, problems to concentrate and headache.The girls reported that they thought that girls of their own age were ?slutty and cocky?, andthey thought that it was important to look good, but at the same time many girls were happyabout themselves and they had realised that they had to live with who they are.Keywords: high-scool girls, stress, groups, self-worth, conformity.

Lärk eller Impregnerat ? en kvalitativt jämförande livscykelanalys av sibirisk lärk och svensk tryckimpregnerad furu

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.

Framtidens energilagring : en studie av befintliga samt potentiella metoder fo?r lagring av fo?rnybar el pa? ett ha?llbart sa?tt

In today?s society there is an increasing demand for renewable energy sources such as sun and wind power. These sources are intermittent, and energy storage is therefore needed to ensure a constant power supply. This report compares pumped hydro energy storage (PHES), compressed air energy storage (CAES), flywheels, batteries, super magnetic energy storage (SMES) and hydrogen energy storage.The opportunities for further development are limited for PHES and CAES in comparison with the other technologies. Lithium-ion batteries and hydrogen energy storage are considered to have the most potential in the future.

Introduktionskurs, underprissättning och institutionellt ägande : samband mellan prissättning och ägande vid en börsintroduktion

Who would not like a profit of more then 95 % in a day? Investors in Sweden had thatopportunity, if they had bought a certain stock on the primary market and sold it on the firsttradable day at the Stock Exchange. Most of that profit fell into the hands of institutionalinvestors. The reason for this extraordinary profit was the underpricing of that specific stockduring its initial public offering (IPO).Our report aims to analyze the relationship between offer price, underpricing and theownership structure of stocks. Our investigation is based on all IPO?s on the Stockholm stockexchange during the years between 2000 and 2005.

Kvalitetskontroll av trafikmätningssystem ? En studie om noggrannheten hos induktiv slinga, slang, KomFram, video och radar i olika trafikmiljöer

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.

Behöver du företag på sociala medier eller behöver företagen dig? : En studie om kunders behov av företag på sociala medier och påverkan på relationer

Social medias impact recent years has been huge and an increasing number of companies have started using the services. The benefits for companies to be available thru social media are many and the costs are low. Social media makes it easier for companies to get in touch with their customers and at the same time they reach out to a lot of people since the number of frequent user?s constantly increase. A major part of the information that is available is seen from a company?s perspective and what benefits they can take advantage of thru social media.

Skötselförslag på utvalda nyckelbiotoper i Kalmar och Kronobergs län.

The objective of this study was to contribute with suggestions of nature preservation managements of selected forest objects of high nature values managed by the Swedish state-owned forest company Sveaskog. Many forests with high natural potential are relatively rare today due to modern forestry, where wood production is the main purpose. Sveaskog?s policy is to consider and to priority nature conservation on valuable objects. This assessment includes objects that in the future may develop into nature reserves.

Trafikverkets effektstyrningssystem - EFS 132 kV : Bidraget till minskade förluster

The technological legacy from the early electrification of the Swedish railroads has resulted in a power grid with a lower grid frequency than the national power grid from which it is fed. Energy transfer between these power grids with different frequencies requires substations, adapting the grid frequency for the rail road power grid. For this purpose, a feeding power grid has been built, stretching across the country from Boden in the north to Tälle/Häggvik in the south.Power transfer in the Swedish power grid results in voltage angle differences which increase with increasing loads and transfer distance. These voltage angle differences are transferred from the power feeding substations to the rail road power grid, will in some extent cause loss of energy due to unwanted power flows from north to south.To minimize the losses due to this phenomenon, a power management system called EFS 132 kV has been developed and implemented. The system minimizes the unwanted power flows and controls the desired power flow for a good distribution of loads between the power feeding substations.This thesis investigates the extent of the transmission losses avoided due to the EFS 132 kV that coordinates the idling angles to a common reference point.The results indicate that EFS 132 kV affects the power flow, especially between the northern substations through an improved load distribution.

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