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2182 Uppsatser om Hydropower reservoirs; dam safety; erosion protection; waves; simulation; MIKE 21 Spectral Wave - Sida 37 av 146

Sakta ner : åtgärder för förbättrad miljö ochtrafiksäkerhet på gator i bostadsområdeni Varberg, idékatalog ochtillämpning

Road safety is the result of measures to reduce therisk of accident and injury. (Nationalencyklopedin,2008). In principle, road safety means to arrive saveand sound.Safe traffic in cities is mainly achieved throughappropriate speed. In Sweden, more than half ofall rides happen with a speed above the legal speedlimit (Holmberg, Hydén m.fl, 1996). To reducespeed in order to increase safety requires measureswhich influence a driver?s motives for his orher choice of speed even if these are not rational(Boverket, 2002).

Bostaden – sedd ur kvinnligt perspektiv

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.

Money vs. Happiness : En fallstudie om CSR på företaget Fair Travel Tanzania

Corporate Social Responsibility (CSR) is about facing responsibilities towards a company?s employees, customers, stakeholders, suppliers and the environment. As customers and consumers came to seek companies that were dealing with CSR a rapid wave of ?forced? implementations of social responsibility began. Fair Travel Tanzania, which has CSR as the foundation of the company, says that they are transparent about what they do and how they give back to the locals, could it be a problem with this? And how do they actually give back to the locals? Is it possible to measure the impact of CSR activities within the company? And if so, how?.

Kvantifiering av föroreningstillskott från dagvatten inom skyddsområdet för Göta Älv : en simuleringsstudie med modellen SEWSYS

The river Göta Älv reaches between Vänern and Gothenburg and is the main raw water source for Gothenburg that supplies about 700 000 people with water. To protect and maintain a high water quality, continuously samples and water analyses are made throughout the river. In 1998 a protection area was founded between surte and Lärjeholm where the raw water intake is. This was made to increase the awareness of the importance to protect the water. However, there is a lot of contribution of untreated stormwater to Göta Älv within the protection area.Göteborg Water and Sewage Works commissioned this thesis where two areas, Tagene industrial area and Kärra residential area, with untreated stormwater outlets within the protection area are studied.

Masibuyelembo : living in harmony - att leva i harmoni

The purpose of this study is to find out how some Swedish preschool teacher discussing how children's Swedish colloquial interaction can be enhanced in the free play. In this case where children are aged three to five.My research questions in the study are:-          What type of free play do preschool teachers talk about in relation to children's Swedish colloquial development?-          What do preschool teachers say about child's colloquial interaction?-           How do preschool teachers reason regarding in what environment children?s colloquial interaction occurs?In my study I have used an interview with elements of a visual method called The Diamond. The approach is that the participants in the interview will be enhanced to discussing about a wise certain number of images. These images are then to be ranked accordingly with a specific theme and terms.If a child has difficult to speak, you can take help of  the interest the child has, the child can tell you and the other children what he or she know about the interest.

Bergerosion i utskovskanaler

Today?s climate changes will probably give rise to precipitation in Sweden, which will cause more floods in Swedish rivers. Many of the Swedish rivers are regulated and have lots of hydro-electro power plants. Higher floods in the rivers will give greater water loads on the dams, which mean that a higher discharge through the sluice gates and in the spillway channels is needed. High discharge of water in a spillway channel can create scour of the material in the channel.

Alternativa dagvattenlösningar för nyexploateringsområden med avseende på substansflöden

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.

Vertikalarmering i tegelbalkar ur arbetsmiljöperspektiv

Statistics of occupational injuries show that bricklayers are among the most exposed, with heavy lifting by far the most common cause of long-term sick leave. Prefabricated brick beams create yet another risk of injuries that can be prevented by auxiliary equipment or alternative solutions. From articles, interviews with masons and from a survey carried out in conjunction with this report, it appears that there are frequently difficulties in the use of available means for lifting and handling. Previous studies on the subject of transverse reinforcement in masonry beams indicate a viable method for bridging large openings in masonry walls. This bachelor thesis delves into whether the idea could be realized in today's brick construction with a view to improving occupational health and safety.

Stadsdelsförnyelse i Norra Björksätra, Sandviken

The housing estates in the outskirts of Sandviken, consist of relatively large scale apartment buildings. This report, that is a B.A. thesis at 10 Swedish university points, aims to investigate and describe the opportunities to improve safety and security for inhabitants in Norra Björksätra. The purpose with this report is to make Norra Björksätra to a more attractive place to live in, by changing the negative trends in the area. Since demolition of at least some of the houses could be of current interest in some years; the purpose is also to investigate whether demolition or renewal of the area is the best solution.

Riktvärden för förorenad mark : En undersökning av hur riktvärden för förorenad mark har förändrats gentemot tidigare riktvärden samt hur de påverkas av variationer i geologiska och hydrogeologiska parametrar

Risk assessment is made to determine risks with contaminated areas and to determine which treatment the area requires. In Sweden, risk assessment is divided into three levels: risk analysis, facilitated risk assessment and detailed risk assessment. In detailed risk assessment site-specific guideline values are developed to compare with values of contaminants that are measured in the area.Site-specific guideline values vary with geological and hydrogeological parameters. The purpose of this report is to examine which of these parameters that affect the guideline values. The examination was done using a calculating program for consideration from the Swedish Environmental Protection Agency from the year of 1997.

Landskapsplanering och konnektivitetsförbättringar inom värdetrakter i Västerbottens län :

According to the Swedish strategy for forest protection, additionally 40 000 ha productive forestland will be protected in the county of Västerbotten, between 1999 and 2010. A national project was carried out to distinguish the proportion of forest with a high biological value, in all counties. The project resulted in demarcation of small landscape areas or small ?biological value regions? (bvr), with higher concentrations of forests with conservation values and red listed species than the surroundings. In Västerbotten, 26 such bvr?s were identified and the Counties Agency and Forest Agency in Västerbotten developed a regional strategy for forest conservation to standardize the forest protection process.

Öppen dagvattenhantering i urbana miljöer :

Storm water causes a number of problems in our country, particularly in city environment with its surfaces of non-absorbing ground materials. At heavy rain falls there are floods due to lack of capacity in the drain system when meeting heavy water masses over a short time. When the drain system is overloaded huge water masses reach the recipient untreated and there causing disturbances in the aquatic ecosystem. Due to emissions from mainly traffic, industries and other human activities the storm water is polluted. Earlier the problem used to be solved technically, by increasing the capacity of the tubes and by construction of reservoirs to delay the floods peaks.

Reglering av turbins ledskenor i vattenkraftverkmed hjälp av elektriska ställdon

Hydropower is the largest renewable energy source available in today's society. Operation and production is handled by high-tech electronics. This thesis is done on behalf of Statkraft Sweden AB who wants to explore the possibility of replacing the hydraulic cylinder with an electric actuator, generally as well as a case of a small power station on the river Nissan. Whether it is the chaplain or francis turbine vanes are actuated by hydraulic cylinders. Because of Gustavsberg hydropower is inconstant operation, this report is based on power calculations, which are read and computed according to the available hydraulic diagram.

Halvledare för höga strömmar i fordon

Mechanical relays are more and more being replaced with semiconductortechnology. In this thesis it is investigated if and how the larger loads couldbe controlled by transistors. The main part of this work aims to create andverify a solution that can control the starter motor, as well as protect it incase of any failure. The different malfunctions that the solution protectsagainst is high current, too high peak current, low current, maximum cranktime and minimum cool off time. The timers also protect indirectly againstoverheating of the starter engine.The transistors used are BTS555, from Infineon.

Positive human to cattle interactions and the possibilities to increase animal welfare, economy and safety for farmers

Cattle production systems are changing to bigger intensified systems with larger numbers of animals per farm and more free range systems while at the same time employing fewer people. Aversive handling has been known to affect cattle production negatively for many years, but lately scientists have started to focus more on what positive effects gentle handling and positive human-cattle interactions may have on beef and dairy production. Fear can cause high stress in production animals and this can contribute to not only reduced production within beef and dairy cattle, but also increased risks for accidents and decreased animal welfare. Therefore, by reducing the fear cattle experience of humans, it could be possible to increase production, decrease accidents and increase the welfare of the animals. Reducing the animals fear and stress can be done by simple means, such as walking and talking calmly around the cattle, associating humans to positive feelings (such as feed) and stroking the cattle?s body regions associated with social grooming.

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