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676 Uppsatser om Wind load - Sida 9 av 46
En jämförelse avseende beståndsgående-och stickvägsgående gallringsmaskiner
The purpose of this report is to investigate and compare the difference between stand-thinning machines and strip-road thinning machines, and how they affect the stand on behalf of future growth, theoretical economic result, wind impact, snow pressure and density of stand.
The investigation is regarding the first commercial thinning of pine stands, after pre-commercial thinning that was well conducted.
The investigation area was located near Katrineholm, Sweden. The measurements that were measured were strength of thinning and amounts of wind throws, snow-breaks and hauling damages.
The results that emerged, was that thinning with strip-road machines had a significantly higher strength of thinning over all, as compared with the stand- thinning machines (45 percent versus 30 percent).
Comparisons between wind-throws, snow-breaks and hauling damages of the stand could not establish any significant differences between the two methods that were investigated.
Conclusions, over all, were that if forest owners want to have more timber volume left for second thinning and final cut of the stand, the forest owners should choose the method with stand-thinning machines. From the point of view of gentle treatment of the stand and ground damages the choice should be the same.
However, the method with strip-road thinning machines is the most common and accessible method in Sweden. Most likely it is the most economical way to manage the stand for forest owners in present time.
If the method with stand-thinning machines is becoming more common in Sweden, it is suggested for forest owners to consider the stand-thinning method as a candidate for treatment due to economic aspects..
Livscykelbaserad miljövärdering av en ny kontorsbyggnad : En jämförande studie mellan två analysmetoder
This Master?s Thesis aims to illustrate in what ways the two Swedish environmental assessment tools, the Environmental Load Profile and EcoEffect differ and if performed valuations gives different results and environmental goals.The built urban environment causes about half the environmental loading in Sweden. The society?s ambition towards sustainable development has resulted in demands reducing the environmental load. One way to accomplish this change is with the assistance of tools for environmental assessment of the built environment.
Verifiering av Kedertakstolen
The Kedertruss is the loadbearing part in the Keder weatherprotectionsystem and it has been analyzed concerning its loadbearing capacity. The Kedertruss is produced and manufactured by Wilhelm Layher GmbH & Co. KG and this report has been made for their Swedish division Layher AB. The Kedertruss, designed in Germany according to German designcode, has been recalculated concerning Swedish conditions according to Eurocodes and a ongoing European standardization project. The two-dimensional program Winstatik Frame Analysis has been used for evaluation of load effects. Capacity has been calculated by hand-calculations and it has been verified that the Kedertruss in its larger spans isn?t able to withstand the loads.
Fuktsäkert byggande : Sjönära bostäder i Östra Hamnen i Västerås
Housing construction very close to the lake Mälaren has become very popular today. One potential problem with these houses is the influence of the sea climate. Unprotected buildings are affected by strong winds and precipitation. So for that reason, it is very important to make an accurate climate investigation and use it for decision-making during the planning of the new settlement.It is very important with a good moisture protection regarding pelting rain, that is the combination of wind and rain. This is more important for buildings close to a lake, as this location normally means a higher exposure to wind.
Urban Vindkraft : ett nytt element i bebyggd miljö?
This paper aims to explore the phenomenon urban wind energy, its visual effect on built environment and the factors that affect the opinion towards new elements in the city. A place study of the city Gävle serves as a complement to the theoretical part of the paper. The theoretical discussion opens with an account for the technical and economical conditions of urban wind energy. It presents the technical basics, different types of turbines and a discussion occurring wind related techniques in built environment. Today, the knowledge of how the wind moves and acts in the rural landscape is quite good.
Terminallokalisering med tyngdpunktsberäkning och kostnadsanalys
The Kedertruss is the loadbearing part in the Keder weatherprotectionsystem and it has been analyzed concerning its loadbearing capacity. The Kedertruss is produced and manufactured by Wilhelm Layher GmbH & Co. KG and this report has been made for their Swedish division Layher AB. The Kedertruss, designed in Germany according to German designcode, has been recalculated concerning Swedish conditions according to Eurocodes and a ongoing European standardization project. The two-dimensional program Winstatik Frame Analysis has been used for evaluation of load effects. Capacity has been calculated by hand-calculations and it has been verified that the Kedertruss in its larger spans isn?t able to withstand the loads.
TOMO Hugglink
Tomo Hugglink (TOMO Skog) is an innovation for harvest and transport of biofuels. The system consists of a truck, a chipping unit and crane mounted on a link and a wood chip trailer. The system works in such a way that the chipping unit is disconnected and placed on the site and wood chips are loaded directly into the wood chip trailer.The aim of this study was:- To examine the performance of the TOMO Hugglink system under different conditions such as the size, placement and quality of the pile.- To calculate the cost per raw ton for two vehicle combinations at different transport distances and to examine the effect of a reduction in set-up time and an increase in load weight.- To identify possible improvements with the TOMO Hugglink system.A time study was conducted within the thesis work to make it possible to determine production and time consumption. In the subsequent economic analysis the cost per tone at different transport distances was calculated for two different lorry concepts. Furthermore the effect of a reduction in set-up time and an increase in load weight was calculated.Under current conditions the utilization of the chipper is low and only 29 % of the total system time is occupied by chipping.
Stadsklimat/Gatuklimat :
The purpose of this paper is to understand the climate of the street and how it can be modified to better meet the needs of the street and the user groups. At the same time the conditions of the street and its surroundings also has to be taken into account. To accomplish this it is necessary to have a broad knowledge of the climate conditions in the city. Therefore an overview of the climate elements and how these are modified in the built-up areas are given. The part of the paper which deals with the city climate has a global approach to be able to give an as complete picture as possible.
CAP KC3-12 : Design and finite element analysis
In offshore oil production FMC Subsea systems use a product called cap. The cap´s mainly task is to protect hubface and seal areas on inboard hub against dirt, corrosion and mechanical damage under installation of a subsea system. A new model of a cap has been designed and analysed using finite element method. The model is called KC3-12 and has a new function, emergency release, which is a backup method for the ROV (remote operated vehicle) to release the cap from the hubface when it is placed under water. The cap KC3-12 was found to fulfil the criteria under the test load pressure, according to ASME VIII, div2.
Nya metoder för vibrationsmätning på vindkraftverk
This project has revolved around finding better ways of overseeing vibrations of the gearbox at a wind power station. The gearbox has been a huge problem at the stations located at Gässlingen and the sooner the warning of an incoming breakdown is at hand the more money you can save from preparations. The work has been carried out together with Askalon AB in cooperation with consults from ÅF. Askalon is a company with a department focused on overseeing vibrations and it is in collaboration with that department the work has been carried out. During this work, new positions for the sensors and new methods of gathering and analyzing data have been worked out. This was then implemented at a wind power station to be tried out on site.
Vindkraft: en undersökning av fem europeiska länders vindkraftutveckling och faktorer som kan påverka den
En del länder väljer att investera och utveckla vindkraftmarknaden mycket, medan en del länder väljer att inte göra det. I Europa startade vindkraftutvecklingen under 1970-talet. Efter en trög start är den europeiska vindkraftutvecklingen nu marknadsledande och fortsätter att expandera i hög takt. Tyskland har den högsta installerade kapaciteten av vindkraft i världen, och Danmark har den högsta installerade kapaciteten per capita. Dessa länder, samt Spanien, Sverige och Storbritannien har alla satt nationella mål för utvecklingen av vindkraften.
Funktionsupphandling av solelanläggningar
This thesis aims to contribute to improved functional procurement of photovoltaic systems, PV systems. Functional procurement means that criteria concerning a function are set rather than specifying technical details or products. Possible advantages and difficulties in using functional procurement have been analyzed by interviews, simulations and a case study. Electricity production and surplus production for different scenarios have been simulated via MATLAB. The MATLAB script was also used to generate rules of thumb on feasible solar fraction for six different load profiles; a church, a farm, a car mechanic, an office, an industry and an apartment building.
Automatisk trimning av drivsystemreglering från MATLAB
This master thesis covers the development of an automatic tuning process for the existing speed controller for drive systems. The drive systems are resonant two-mass systems where a motor is used to drive a load connected by a shaft. The developed method relies heavily on system identification and the construction of a complete mechanical model of the process. With this approach, the common problem with poor load speed control that derives from measuring only the motor speed can be addressed and solved for a majority of such processes.The automatic tuning method has along with general test functions been implemented in a complete tool for automatic tuning, testing and performance evaluation and reporting for drive systems..
Beräkningsmall för vindlast enligt Eurokoder samt jämförelsestudie av vindlastberäkningsmetoder
Detta examensarbete har genomförts i samarbete med byggteknikavdelning på Ramböll Sverige AB, i Norrköping/Linköping. På företaget finns ett behov av att förenkla arbetet med vindlastberäkningar för hallbyggnader enligt Eurokoden. Idag använder företaget en förenklad metod som överdimensionerar. För att kunna göra en mer exakt beräkning helt enligt Eurokoden och effektivisera arbetet har det i detta examensarbete skapats en beräkningsmall för detta ändamål. Beräkningsmallen har tagits fram i programmet Microsoft Excel.För att också kunna se konsekvenserna av att jobba med en förenklad metod, har det utförts en jämförelsestudie mellan två befintliga projekt på företaget.
Kundanpassning av ett rehabiliteringsverktyg
To be able to move around without having to think about each movement is for most people amatter of course. Todays society contributes to a life at high speed where the sparetime is oftenspend doing somekind of sport, even extreme sports which earlier only a few people wheredoing. This leads to not only good health effects but also to more injuries. One of the mostcommon injuries is the knee injury.Capio Artro Clinic is a clinic specialized in sports medicine and particulary patients with injuriesin knee, shoulder, foot, hip or elbow. They perform a great part of all the crucial ligamentsurgeries in Sweden and has therefor also a lot of patients in need for rehabilitation of the knee.During the rehabilitation the load of the injuried knee is increased in steps.