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1616 Uppsatser om Surface water - Sida 54 av 108
Kompensering av reaktiv effekt vid vindkraftverk
Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.
Möjliga alternativ för att ersätta direktverkande el i flerbostadshus
I have in my thesis, examined the possibilities in terms of energy for a condominium association.To have an effective and good energy is becoming increasingly important with today's rising electric and oil prices. In my thesis I have used the condominium association Kärralyckan, which is situated in Falkenberg. The buildings at Kärralyckan are built in the mid-1970s, and are heated by electric radiators. The tap water is heated by an electric boiler.Based on that calculation I can show the various energyststem. The different solutions have been developed by contact manufacturers and installers through phone calls and e-mail.According to the results shows that geothermal heating has been a great solution for Kärralyckan.
Skadehändelser och preventiva åtgärder bland fotgängare och cyklister i Umeå kommun
Every year, approximately 700 000 individuals´ visit an emergency ward in Sweden as a result of injuries and to the emergency ward at Umea University hospital (NUS) about 12 000 injured arrive every year. This study is a retrospective cross-sectional study that surveys injuries caused by crashes among 153 pedestrians and 53 bicyclists, who have been injured in a geographically well defined area during the period January to June 2009. The aim of this study is to survey injuries among pedestrians and cyclists and to examine what preventive measures could reduce these injuries in the Umeå municipality. The results show that falls caused by slipper surface are common among both pedestrians (71 %; n = 109) and bicyclists (32 %; n = 17). Almost one third of the pedestrians (34 %; n = 43) were in the age of 65 or older.
Man blir påverkad av sitt kön vare sig man vill eller inte : En kvalitativ studie om skillnader i män och kvinnors musikpreferenser
Music has always been an important form of communication and it can be found in many different contexts including aesthetical, cultural and emotional forms. In the globalized society of today music can be distributed fast through radio, TV, CD: s and the Internet. For many people consumption of music is an important part of the daily life and it can contribute to shape an individual?s attitudes and personality.The main purpose of this study is to find out whether there are any differences between men and women?s musical preferences. I will apply an explorative approach using qualitative interviews to describe what causes the differences.
Munksjökajen : Stadsplanering i Jönköping
Munksjökajen is an old industrial estate on the western shore of Munksjön in Jönköping. The purpose of this thesis is to develop Munksjökajen in accordance with the program for Jönköping?s future development ? Stadsbyggnadsvisionen ? drawn up by the city council.Munksjökajens relations to the surrounding areas have been investigated as well as the need for public transport and possibilities for commercial, municipal and private businesses to operate in the area.The final proposal has a relatively high degree of preserved industrial buildings. New buildings vary in shape and expression in order to create an interesting and diverse environment. The proximity to the lake adds character to the neighbourhood and the water is accentuated by the integration of it in the area..
Social hållbarhet och förtätning : en kritisk studie i förtätningens sociala paradoxer
Densification is one of the urban visions for sustainable development - a vision that has become a part of the solution to the unsustainable sake dilemma. With the dense city land will be saved, energy consumption reduced and social cohesion improved. The dense city is considered to be ecologically, economically and socially sustainable. Applying an urban design concept has thus proven to be problematic. Density has been found to be a complex concept
which is far more complicated than measuring how much built surface that needs to be covered.
It is also not disputed what different degrees of densification mean and whether densification in itself is sustainable.
Värmesystemsutveckling
In cooperate with Asko Cylinda we have developed a new heat system too short the process
time and reduce the energy consume in a dishwasher and still have it too be a class AAA.
The environment and quality is important for the company too still be the number one on
the market, If they want too keep that position the product developed of new innovations will
be very important. The systems we have developed are more effective and reduce energy up
too 25 %. The process time is reduced too less than two hours, from the today two and
half-hour. The solutions are too heat up the rinse water and the dishwater at the same time,
with a new heating system and it make are solutions unique and effective. Its good for the
dish and the environment.
Testplattform för nätverks-RTK i syfte att ge en rikstäckande GPS-tjänst med centimeternoggrannhet
Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.
Deaktivering av metanisering katalysatorer
A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.
Trafiken till Göteborgs södra skärgård - En annorlunda kollektivtrafik
Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.
Vattnets väg genom ett romerskt bad. - tekniken bakom marmorn.
This essay focuses on the technical systems and functions behind how a Roman bath operated. I will present a general view by going through each part of the waters path through the bath one by one. Since there is no such thing as a standardised Roman bath I will, under each headline, present the sub subject with a presentation of the workings and then exemplifying through archaeological findings and ancient literary sources.This essay is therefore meant to present a thorough and clear presentation of the technical aspects of a roman bath. The aim is to give the reader an understanding of how a bathhouse worked in general and why. To this I want to present problems that the Romans were faced with and how they solved them..
Val av överlastskydd för elektriska ventilmanöverdon på kärnkraftverket i Forsmark
At nuclear power plants, electrical valve actuators are important for ensuring that the reactor core is water covered and the pressure in the reactor tank and containment is limited. The electrical actuators are provided with overload protection in case of drawing higher current then the motors are rated for. When safety manoeuvres are needed, the overload protection must not trig and cause the valve to stop before completing the manoeuvre. Analyses have showed that the current settings of the overload protection may cause an illegitimate trig at the worst theoretically possible accident. A new method has been developed with conservative assumptions and applies overload protections for all electrical valve actuators at the three reactors in Forsmark..
Förändringar och Förvillelser : Skriftspråkets modernisering mellan år 1895 och 1938 i en roman av Hjalmar Söderberg
This essay ? Discourse and Dissonance ? deals with Mary Shelley?s gothic novel Frankenstein; or, the Modern Prometheus (1818). The focal point is the construction of ?Them and Us?, as defined by scholars such as Stuart Hall, viewed in terms of the following categories: race, gender and family, class, and sexuality. Rather than applying an outside perspective, e.g.
Effekt av biotopvård på öringpopulationen i två vattendrag
I have done a follow up study of the restoration of two rivers, Röälven and Grundan, in order to evaluate the effects of the restoration on the endemic population of trout. Both rivers have been used for timber floating during many years throughout the 20th century, and because of this, had all obstacles such as rocks and wood parts removed. In 2004-2005 both rivers were restored, and rocks and wood were put back into the rivers. Spawning grounds were created and boulder dams were constructed to promote the streaming water. The result showed that the trout population of both rivers increased after the restoration, but also that the trout population of Röälven increased more than that of Grundan.
Sådd av tallfrön med vattenryggsäck : en laboratoriestudie
Föryngring av skog är en nödvändig, men kostsam åtgärd och därför är det eftersträvansvärt att hitta en föryngringsmetod som är både kostnadseffektiv och ger en bra föryngring. Ett sätt att få en billigare föryngringsåtgärd är att använda frösådd. Vid en lyckad sådd gör det stora plantuppslaget att plantorna får bra förutsättningar för god kvalitet. Dessa plantor får dessutom bättre rotutveckling och stabilitet än planterade plantor. Användningen av skogssådd är dock begränsad av bl.a.