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4571 Uppsatser om Vilhelmina Model Forest - Sida 19 av 305

Stubbskörd : från modell till verklighet

In the near future we need to reduce the greenhouse gas emissions significantly for the benefit of the environment around us. The European Union has de-manded a variety of climate and energy goals to be achieved by year 2020, the ?20-20-20? targets. With these aims, The European Union means that we must reduce our emissions from fossil fuels and instead increase our renewable fuels. With stump harvest in the forest it?s possible to increase the use of renewable fuels and reduce our emissions from fossil fuels.

Att återställa en naturlig ordning : skogshistoria och restaureringsbränning i Långsidbergets naturreservat

During the late 1800s fire suppression became increasingly effective in northern Sweden which led to decreased areas of fire-disturbed woodland and successive changes in the structure of forests. In the long run this can pose a serious threat to fire-dependent and fire-favored species. Today some fire-prone forest reserves are burned as a nature conservation act. Often partial cuttings are made before burning, with somewhat different motives. The purpose of the study in Långsidberget nature reserve was to give a general picture of forest history and its affect on today?s forest condition, and to show how partial cuttings affect burning conditions and results. Långsidberget is located close to areas that were colonized during the Middle Ages.

Spegelvändbart PTO ? Konstruktion av kraftuttag till automatiska växellådor

Over 90% of forestry work is carried out today by contractors, thereforeclear agreements between the client and the contractor it is of utmostimportance. Contract Packages for work within the forest sector (APSE) is acollection contract templates that the industry jointly developed for thispurpose. The purpose of this thesis is to examine how forest contractors doto keep themselves updated of the current laws and government regulations,which channels are available to accomplish this and what possible obstaclesmay occur. 20 interviews were conducted with contractors engaged inlogging. The results show, among other things, the availability of and whichchannels most contractors use out of which aggravating circumstances existand how strong they are perceived and what is expected of the client in thisregard..

Utveckling av ett verktyg som underlättar vid lyft och montering av en pump

Over 90% of forestry work is carried out today by contractors, thereforeclear agreements between the client and the contractor it is of utmostimportance. Contract Packages for work within the forest sector (APSE) is acollection contract templates that the industry jointly developed for thispurpose. The purpose of this thesis is to examine how forest contractors doto keep themselves updated of the current laws and government regulations,which channels are available to accomplish this and what possible obstaclesmay occur. 20 interviews were conducted with contractors engaged inlogging. The results show, among other things, the availability of and whichchannels most contractors use out of which aggravating circumstances existand how strong they are perceived and what is expected of the client in thisregard..

Riskmodell för kabelsträckningar i mellanspänningsnätet i Sverige

The society of today is largely dependent on electricity and the dependence does not show any signs of declining. Reliability of supply will become increasingly important in the future and it is therefore important to investigate factors affecting the failure rates in electrical components.Sweden was hit by several severe storms during the 00?s. As a result of this many overhead lines in forests were cablified. In urban areas underground cable systems have been the norm for many years.

Tillvaratagande av GROT i skärgårdsnära miljö :

The main aim of this study was to investigate and compare different methods for the extraction of forest fuel from environments close to an archipelago. The study was based on relevant literature and published reports as well as personal communications. Forestry has traditionally been characterized by intense efforts to rationalize and mechanize the cutting technique used for timber and pulpwood. In line with the increasing importance of forestry, more concentrated efforts can be expected in the area of techniques and methods, especially for the above-mentioned product lines. In Sweden, forestry is of major importance and the Swedish economy and standard of living have mainly been created based on the revenues generated from it. Thus, it is vital that Swedish forests are harvested in an efficient and responsible manner. The demand for biofuel is growing and today accounts for 15% of total Swedish energy production, a share that will probably increase. This study is based on three research questions, which are described under the heading of Aim. The results reveal that the most profitable method for handling forest fuel is the traditional one, which is also the most commonly used method in southern Sweden, namely the stockpiling of logs in a clearing by means of forwarders followed by splintering at the place from where they will be distributed. Today, the high cost of barge transport required for the extraction of forest fuel in an archipelago environment renders such operations unprofitable.

Utvärdering av svensk vindkraft : Skillnaden mellan skogs- och traditionella placeringar

During the last years commercial Wind Power Turbines (WPT) has become larger regardingto the generator sizes and hub heights. Available hub heights around 100 meters is nowcommon, which has led to profitability for WPT located in forests where there normally are tolow wind speeds. The current knowledgement regarding turbulence and the variation in thewind profile for the outcome of the power production for the WPT in forests is limited.In this Master of Science thesis an investigation concerning forest located wind power plantshas been made. The purpose has been to investigate if plants located in forest perform lesscompared to wind power turbines located at more common locations.The analyses are based on statically material for determining the availability,production/generator size, production/hub height, production/swept area and how thetopography affect the production results.The analyses show that the variation in production result for WPT located in forest comparedto turbines located at other locations is small. The availability is high and the productionresults are good..

Omfattningen av icke avverkade områdeni samband med slutavverkning :

This final thesis is performed on commission of Torsby forestry administration, Stora Enso Skog. Stora Enso Skog is one of the major forestry companies of Sweden. The main business area is located in and around the region of Bergslagen. During the last decade the practice of forest management has rapidly changed due to a new forest legislation. The new law has resulted in that the production goal is equal to the environmental goal within forestry.

A Long Day?s Journey into Night ? examining the Swedish model, present and future

In this essay we strive to examine how the social work in Sweden will be affected if the Swedish welfare model goes through fundamental changes. The study illuminates the close connection between the Swedish collective bargaining model and the Swedish welfare system. The questions we present in this essay, and hopefully answer satisfactory, are: is the Swedish welfare model subject to thorough changes? How will such a change alter the social work in Sweden?, is the Swedish collective bargaining model in a state of modification? Would a modification in the collective bargaining model have effects on the Swedish welfare model?We have used a qualitative method in collecting empirical material. We interviewed three representatives, who worked for Confederation of Swedish Enterprise, IF Metall and The Swedish Municipal Workers respectively.

Gestaltningsförslag för Bölekläppen : utveckling av upplevelsevärden i ett friluftsområde i Umeå stads utkant

Taking a qualitative approach, this research investigates different theories and methods for creating parks that people will cherish and visit during their daily life. It also takes on the task to understand how principles of developing recreational values in a small forest is affected by the addition of a new element to the landscape, i.e. a major highway. Data was collected through the combination of focused literature review and study trips. This provided a framework which in turn was applied to the subject of the study, i.e.

Jämförelse mellan MultiScat och konventionell beräkning av intensiteter till koncentrationer vid analys med röntgenflourescensspektrometri

In this master thesis work, a new method called MultiScat, is compared with the conventional method with alfa-correction, for computing concentrations from intensities in X-ray spectrometric analysis. The conventional model is a linear model, which only takes the photoelectric effect into consideration. It doesn't consider Rayleigh and Compton scattering even though it has a great impact on the measured intensities. Here MultiScat differs a lot. MultiScat is based on a solution of the Boltzmann transport equation.

Svamparnas roller i svenska barrskogsekosystem : hur ser kunskapsläget ut hos några olika grupper människor?

Fungi are everywhere around us and recently, there has been an increased interest in their role and importance in the forest. The fungi have several strategies to acquire energy and nutrition; one example is a mutual symbiosis with trees and plants - another being dissolving organic materials. Attempts have been made to better understand the circulation of nutrition in coniferous forests, and how fungi cooperate. Trees and plants have adapted with mycorrhizae and are now interdependent which is important to consider in forestry. A great number of fungi depend on dead wood and old trees to set fruiting bodies and spread further. These fungi also create environments for other species, such as birds and insects. The vegetation of a forest is determined by a series of factors; tree species, how old the forest is, soil type, as well as the ability of the fungal spores to spread and establish. Furthermore, in determining vegetation, the fungi?s ability to compete in the soil matters. These factors are nearly unexplored. Researching fungi knowledge and interest, a survey was distributed to five groups of people. The groups included forest owners, high school teachers, high school students, senior citizens, and a fifth group - ?o he ? - consisting of people of mixed ages and backgrounds.

Barns tolkning av en modell för vattnets kretslopp : -förståelse och tillämpning

AbstractThe purpose of this study is to find out how pupils give expression of a water cycle model and if the model causes any misunderstanding. Two problems constitute the starting point for this investigation. The first question is: how do the pupils explain the water cycle with the help of the jar model (can of glass). The other question is: can the children see any similarities between the can of glass and our earth. Qualitative semi structured interviews with seven pupils in the ages of 8-9 have been used to show the pupils? own thoughts and how they express them.

Transferfunktionsmodeller modellering och prognoser av Sjötransportindex

We have by Statistics Sweden (SCB) been given the task of using different dynamic regression models in order to forecast service price index for sea transport. The aim is to see whether these models provide better forecasts than those previously used. This essay aim to identify, estimate and evaluate the selected prediction models. Through our data material we were given access to 28 sightings of sea transport index during the period of 2004 q1 to 2010 q4. We have chosen to evaluate three different transfer function models, one ARIMA model and one naive forecasting model. The input variables we decided to test in our transfer function models were the price of petroleum products, the port activity in Swedish ports and the lending rate of Swedish Central bank. The results of our study suggest that transfer function models generally provide better models than the ARIMA model and the naive forecast model.

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..

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