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676 Uppsatser om Wind load - Sida 24 av 46
Teoretisk och experimentell utvärdering av Lättelement AB:s takinfästning
Lattelement AB in Ornskoldsvik is one of the leading companies in Sweden in composite elements in walls, floors and roofs in particular. The company supplies elements to buildings located with a wide geographical variation, which means that the products are subjected to very different climate with regard to snow, wind and humidity. This places high demands and requires the elements to withstand large variable loads.The elements are made of lightweight beams with flanges of structural timber and beam webs made of OSB. These are bound together by nogging pieces with the same kind of structure. On top of the beams a nailed and glued plywood is added to absorb compressive forces and on the underside of the element a sheet of steel is added for tensile absorption.These elements are then attached to the building framework in different ways depending on the particular element height, loads and the structual supporting material of the frame work.
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.
Inflytande av sommarväder på kornas val att vara på bete eller inne dagtid i en besättning, samt studier av andningsfrekvens och yttemperatur hos fokaldjur :
SAMMANFATTNING
När man i tidigare undersökningar studerat betesgång för mjölkkor har klimatet på betet inte
beaktats. En höglakterande ko producerar mycket värme som hon måste avge till sin
omgivning för att kunna bibehålla sin kroppstemperatur. De sätt som djuret kan avge värme
på är begränsade och påverkas av flera klimatfaktorer samt djurets genetiska och biologiska
förutsättningar.
Antalet dagar som registreringar gjordes under denna studie blev av flera olika anledningar få,
18 dagar. Klimatet utomhus under studien registrerat som globtemperatur varierade från 22,4
till 34,7ºC.
Då djurskyddslagen skall främja djurens hälsa och djurets naturliga beteende fick en grupp
126 höglakterande kor möjlighet att välja uppehållsplats under tiden 26 juli till 11 augusti.
2004. Korna fördes ut på betet vid niotiden på förmiddagen och var därefter fria att gå in och
ur stallet efter egen vilja tills de togs in för kvällsmjölkning omkring klockan tre
påeftermiddagen.
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.
Självscanningssystemet : Dess för- och nackdelar
The purpose with our thesis is to understand and explain the advantages and disadvantages there is with the self scanning system. The advantages and disadvantages we will highlight from three different angels; the store management perspective, the staff perspective and the customer perspective. These three perspectives will together form an overall perspective over the advantages and disadvantages as the self scanning system has contributed with. Finally we will highlight the differences and resemblances we have found between the perspectives.Through a qualitative approach we have gathered data to our thesis. Furthermore we have based our theory chapter and our empirical chapter on the base of Grounded Theory.
Standardisering av snöröjningsplan : Instruktioner, råd och tips för snöröjning av tak med stora spännvidder
The Swedish winters 2009/10 and 2010/11 were rich in snow and many roofs collapsed, mainly largespan frames. Investigations were made and the amount of snow was not the primary cause, insteadthere were several other causes. One of these was that in some cases roofs were shoveled in anunfavorable manner which affected the load patterns negatively, so causing the roofs to collapse.Most people lack the knowledge of how shoveling will affect the roof. Had there been an increasedunderstanding regarding shoveling, some roofs could have been prevented from collapsing.Through both qualitative and quantitative research in the form of interviews and calculations thetheoretically best ways to shovel a selection of roof types is presented in the report. The roofstructures covered are 3-compartment, continuous and Gerberspliced metal roof decks.
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.
Skadeanalys och omkonstruktion av HMS Belos A-ram
In order to rescue a distressed submarine crew, the Swedish Navy is able to use a deep submergence rescue vehicle, DSRV. This mini submarine ascends, docks to the downed submarine and picks up the whole crew. The submarine rescue ship HMS Belos has a special crane located in the aft of the ship to lift the surfaced DSRV aboard, which then docks on to the on board pressure chambers located below deck. During inspections the aforementioned crane has shown to have problems with cracks in the structure, most of them located in the bolted joint between the top part of the crane and the two leg parts. A simulation of the forces acting on the structure in heavy sea condition was conducted; these values were then used as input values in a Finite Element Method, FEM, analysis of the joint.
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.
Människovana grävlingar som testdjur för grythundar. En studie om hur grävlingars beteende och fysiologi påverkas av hundars aggressivitet
In Sweden live badgers are used in tests in order to train and prepare earth dogs for hunting underneath ground. This has for several years causeddebate concerning the welfare of the badgers. It is questioned whether the purpose of the dog training, i.e. to reduce injuries in both dogs and prey, is worth the suffering that is reflected on the badgers. The aim of this investigation was to study 1) stress levels in badgers when used in earth dog training, 2) if the stress load differs when the badgers are exposed to dogs with varying aggression levels (low, moderate, high).
Utmattning av vägbroar i armerad betong enligt eurokoder
Since 1 January 2010 it is a requirement to use the European standards, Eurocodes, in Sweden when constructing bridges. One chapter that has caused an extra amount of problems for the engineers is the one about fatigue analysis, which resulted in us doing this thesis.To do this we had to read all of the Eurocodes that direct, or indirect deals with fatigue and calculating of such. We have read the background documents for the Eurocodes and master?s thesis in the subject. We also studied the calculations of bridges constructed by different construction firms.We have chosen to limit the thesis to discuss only road bridges made of concrete due to the lack of method for verification of concrete in the national appendix.