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367 Uppsatser om Wind erosion - Sida 18 av 25

Självförsörjande elgenerering : Kan Orust bli självförsörjande på förnybar el?

Orust Kretsloppsakademi is a nonprofit organisation, with a goal of annually generate the same amount of electrical energy that is consumed. Orust is an island on the west coast of Sweden, north of Gothenburg. The population of 15 000 reaches 40 000 during summer, due to the large amount of vacationer. The total electricity demand is 174 GWh a year with a maximum power need of 32 MW. This report presents an analysis for the plausibility of their plan and from a power system stability perspective, the effects on the electrical grid.The conclusion is that the restraints for development of power generation from wind, solar and wave generation, are the power systems capability to transfer power, primarily in the transformers of the grid.

Ute och cyklar? : på jakt efter en metod att mäta upplevelse

Well-functioning bicycle paths are relevant issues in today´s society as a way to increase active transport. Active transport means working for a better global climate, urban environment and public health. What we experience on a bicycle affects the choice of a bicycle path and is a subject where there is much left to explore. This essay examines methods in environmental psychology literature that measure the experiences of landscape. The aim is to find and apply methods to measure the experience of two bicycle paths in the Skåne plains.

Konstruktion av instrument för dragprov på nervceller

This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.

Modellbaserad drivlinereglering

A cars powertrain consists of everything that is needed for its propulsion. The components in the driveline that transfer the power from the engine to the driven wheels are not absolutely stiff, hence they will wind up due to the torque and act as torsion springs. If you suddenly demand a bigger torque by stepping on the accelerator pedal, a so called tip in manoeuvre, and that torque is acquired from the engine as quickly as possible, the driveline will not be able to transfer that fast torque change due to its weakness and as a result it will start to oscillate. These oscillations will be transferred to the driven wheels and make the car to accelerate jerkily which will be experienced as uncomfortable by the passengers. Furthermore, there is a backlash in the driveline that will make the weakness in the driveline even more excited than it should have been if the backlash did not existed.To avoid too big problems with these oscillations there is a control system that controls the demanded torque.

En undersökning om fallolyckor med gångtrafikanter

The purpose of this study was to investigate different relations between the damages of falls and background variables as well as the relation between the falls and the weather condition to later be able to use this report to expand the knowledge among workers at VTI about the pedestrian fall injuries. All of the fall injuries in the data that this study is based on have occurred in Sweden during the time period between January 2003 and December 2011.To be able to answer the questions that this report is based on several statistical methods are used. The statistical methods that have been used during the making of this report are multiple linear regression, binary logistic regression, correlation analysis, association analysis and descriptive statistics as well as visual analysis.The results of the study show that women around menopause age have a tendency to get a big increase in the amount of injuries compared to men of the same age. The study also suggests that men on average tend to have a lower level of injury compared to women.Age also seems to affect both the amount of injuries and the level of injury negatively. The study suggests that the most likely reason for this is both that the intake of ?Fall Risk Increasing Medicine?, which is medicine that increases the drowsiness, is higher among older individuals as well as lower estrogen levels among older women and lower amount of testosterone among older men, which causes a loss of bone density in both sexes.The weather seems to have a strong effect on how many injuries occur but also a noticeable effect on the scale of the injury.

Smarta elnät i Sverige : Energibranschens förutsättningar och förväntningar

The need for a more efficient electrical grid has made the smart grid concept popular in recent years. The aims of this study are to identify the conditions in Sweden for implementing a smart grid and to analyse the opinions of stakeholders. One finding is that the large capacity of Sweden?s existing electrical grid decreases the immediate need for smart grid solutions. However, the rapid increase in wind power might push the development of a smart grid in the coming years.

Resonans

This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.

Erfarenheter av utedrift med köttdjur i Sverige och Kanada :

Beef cattle wintering outdoors should be provided a shelter, e.g. a type of barn or corresponding. This type of production requires appropriate soil types and secured animal welfare. For example, a clean and dry resting place needs to be provided to the animals. To receive an exemption for buildings the farmer has to have something equivalent that provides an adequate shelter.

Koldiffusionens inverkan på utmattnings-hållfastheten hos varmvalsade sexkantsstänger;The influence of carbon diffusion on the fatigue strength of hot rolled hexagonal rods

Helstångsborr och konstång kallas bergborrverktyg, som tillverkas av sexkantiga stänger med inre hål för ledning av spolvatten. Dessa spolhål är klädda med ferritiskt rostfritt stål. Innan valsning borras ett centrerat hål i stålämnet som ska valsas. I det borrade hålet appliceras ett rör av ferritiskt rostfritt stål och i det röret skjuts en manganstålskärna in. Efter valsning dras kärnan ut och ett spolhål med invändigt foder av rostfritt stål bildas.

Påskön. Myten om Rapa Nui

This essay will examine the historical picture of the island Rapa Nui as it is portrayed in popular science and in ecohistorical literature of the university of Gothenburg. This historical picture states that the inhabitants of the island cut down a lot of trees in the process of transporting the big and heavy statues, moai, from the quarry to the platforms along the coastline of the island. During this process all trees disappeared and resulted in soil erosion. The cultivation was destroyed and brought hunger to Rapa Nui. The following rivalry for food led to a situation of war followed by a cultural collapse.

Design av utomhusträdgård i Dubai :

To plan and build a garden in Dubai has other conditions and challenges than what you experience in Sweden. The heat, wind and lack of water makes the need for durable plants, a good design and landscaping important if you want to have the opportunity to use your garden during most of the year. The soil is poor of nutrients, alkaline and sometimes saline, witch makes supplying the soil with organic material and various fertilizers necessary if you want to be able to plant a bigger range of plant material in your garden. Another important part is to provide your garden with a good irrigation system that should be put into the ground before planting so that the plants are given a more even irrigation. It?s relatively green scenery you meet and to me it?s in a way surprising since the country with its climate is rather harsh for the purpose of supporting plant life.

H2 För racing

AbstractMotor sports have been around as long as motor vehicles have been. Sports are often seen as costly polluter but in the same time the motor sports have encourages a large part of development, both for vehicles and other industries. Inventions like rear mirror and ABS brakes come from motor sports. One way to once again drive development forward while making motor sports carbon-neutral is to run the race cars on hydrogen. In this thesis, the goal is to convert a spark ignition engine for hydrogen operation.

Tilla?mpning och simulering av naturlig ventilation : Potential fo?r utnyttjande i kontorsrum

Mechanical ventilation is the most common type ofventilation in newly constructed office buildings. Therehas been an interest to utilize natural ventilationinstead of mechanical ventilation among architects andHVAC consultants in recent years. This is due to thesize of mechanical ventilation systems, which arespace consuming. The mechanical ventilation system isalso complex and requires maintenance. Furthermore,the fan uses a considerable amount of energy.

Hörneborg - borg eller lada? : kolanalys, magnetisk susceptibilitet, sjösänkning och historiska kartor.

Hörneborg ligger på en udde i sjön Hörnsjön i Olofströms kommun i Blekinge län. En utgrävning av borgen gjordes 1997 för att fastställa funktion och ålder. 14C dateringar visade att borgen var byggd cirka 1030-1250 e.Kr. och förstördes genom brand någon gång mellan 1290 och 1420 e. Kr.

Solceller pa? Uppsalahems fastigheter : Ekonomisk potential fram till 2030

Uppsalahem is the leading housing corporation in Uppsala with its over 160 real estate properties. Uppsalahem is owned by the municipality of Uppsala, which has a climate and energy goal that aims for 100 MW of solar energy to be installed in Uppsala by 2030. The 100 MW goal, combined with Uppsalahem?s environmental policy, is a strong incentive to investigate the possibility of installing PV modules on the many available roof areas that Uppsalahem possesses. The objective of this thesis is to create a foundation for future decisions regarding PV systems for Uppsalahem.

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