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254 Uppsatser om Density - Sida 11 av 17
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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..
Hunter demography, trends and correlates of hunting participation in Sweden
The concerning issue of declining number of hunters in North America is also apparent in Europe and Sweden. When the bulk of research found on human dimensions and hunting participation has almost exclusively been done in the United States, this report seeks to add to the needed knowledge on a national level focusing on the causes of hunter declines related to social factors within Sweden. Using hunter data reaching from commune, county to National level, this report describes the correlation between a number of variables and the hunting participation in Sweden.The typical Swedish hunter lives in an area with low population Density, the person usually has higher education, the living situation is stable with no recent moving and there is relatively good access to forest land. Persons with weaker connection to the Swedish culture such as foreign citizens, people with foreign background and people born outside ?the Nordic countries? are less likely to start hunt or participate in hunting.A strong relationship was found between the favorite game, moose (Alces alces), and the amount of hunters participating in the hunting.
Påverkas mosippa (Pulsatilla vernalis) negativt av igenväxning?
Pulsatilla vernalis is one of several endangered plant species that benefit from wildfires and small scale disturbance events that repel competing vegetation and create open patches in the vegetation cover. Previous studies argue that Pulsatilla vernalis is decreasing in numbers due to vegetation changes associated with the decrease in wildfires, forest grazing and changes in forest management. In this study, 17 populations of P. vernalis were inventoried in order to examine if soil and/or vegetation structures affect the population structure of P. vernalis (i.e.
Beräkning av direktljud genom homogena betongväggar : Densitetens och tjocklekens påverkan på reduktionstalet
Today's urban centers become denser, which contributes to higher demands on sound and noise. It is therefore highly relevant to build homes with good sound environment while maintaining living space. This thesis aimed to reduce the current concrete walls and see how the mass law affects the reduction index value and flanking transmissions. Handmade calculations were calculated according to the Swedish standard SS-EN 21354-1, where only air sound was calculated.Calculations were performed on wall elements with different weights and thicknesses, and compared with results from Bastian.In Bastian calculations of flanking transmissions were also made, this was made to see the impact of the flanking transmission when changing the mass per unit area. Mass law's impact was examined by flanking transmission and the result shows that they are not affected as long as the ratio between the thickness and the Density remains the same.A questionnaire survey was conducted to determine the actual sound experience; this questionnaire was conducted on three concrete buildings in Växjö.
Stockholms förtätningsideal i strävan mot hållbar stadsutveckling : En studie om sambanden mellan den täta staden och Stockholms parker och offentliga grönområden
Syftet med denna studie är att undersöka sambandet mellan Stockholms parker och offentliga grönområdena i relation till den rådande förtätning staden genomför. Stockholm har en tydlig strategi på att skapa en tät stad vilket medför effekter på stadens parker och offentliga grönområden. Studien diskuterar de värden som tillkommer och går förlorade när exploateringen av staden ökar samtidigt som den totala arealen grönområden minskar. Vidare diskuteras det offentliga grönområdenas funktion i den täta staden. De metoder som använts i studien består av semistrukturerade informantintervjuer i kombination med telefon- och e-postintervjuer följt av en bred litteraturundersökning.
The distribution of Moose (Alces alces) during winter in southern Sweden : a response to food sources?
The traditional Swedish way of dealing with browsing damages made by moose, is to reduce the moose population. However, a growing way of dealing with damages made by several ungulate species, including wild boars in particular is to redistribute them with supplementary food sources. Attracting them to settle in habitats less vulnerable to damages made during foraging. This study we tracked collared moose in southern Sweden from January throughout April in the year of 2009. From the tracking data their ?favourite? positions was selected and visited in order to study the features that attracts moose during winter.
A risk analysis of moose close to roads
For many decades the increase in traffic volume, expansion of highways and infrastructure has lead to an increase of wildlife vehicle collisions which are unfortunately very common in many countries today. They cause great deal of material damage and even kill humans or wildlife. Measures in the form of warning signs, under- and overpasses and fencing have been implemented for a long time with the help of observation by hunters and collisions sites. However this study focuses on the moose?s perspective and the variables that, both spatially and temporally, could have an effect on why and when moose are close to certain types of roads.
Läroboksspråk : En studie av språket i två historieböcker avsedda för grund- respektive gymnasieskolan
This essay investigates and compares the readability in two different schoolbooks: Eko Historia (the primary school grade 4-6) and Epos Historia (the upper secondary school). The questions of the survey are:- Which differences in linguistic and layout can be found between books meant for the primary school and books meant for the upper secondary school?- Are the texts easy to read according to the former research in readability?In order to answer the questions structural dimensions as lexicon, syntax, bounds between sentences and narrative voices have been studied. Also the texts disposition and typography have been examined.The results demonstrate that the book designed for the primary school has a verbal structure with an explicit vocabulary, lots of verbs and short sentences. A clear narrative voice gives an impression of spoken language.
Intelligent vattendesign : utformning av Gjutarplan i Kallhälls centrum
The thesis aims to be an informative study for landscape architects and hopes to contributeto an understanding of ways water can be used and managed at sites lacking open, greensurfaces.The title "intelligent water design" should evoke the reader?s thoughts concerning intelligentaspects of water. Text, images and the design proposition give hints about these aspects.In the first part of this thesis, various examples of water design are presented. The chosenexamples are all applicable in urban environments with a high percentage of impervioussurfaces.The second part examines Gjutarplan, an urban square in the centre of Kallhäll, in Järfälla,north of Stockholm. Gjutarplan is first framed in a geographical and historical context.
Rekreationsanpassad skötselplan för Skedalaskogen :
In this master thesis we suggest a recreational directed forest management plan for the
Skedalaskogen. The forest is situated 10 kilometres east of the city of Halmstad and is owned by the municipality.
We have in literature and in research investigated what people like and want in the forest, how to manage the forest for recreation according to for example tree species, mixtures and Density. We tried to adapt the forestry methods more to recreational thinking. We have also looked at issues like what is rare and not rare in this part of the country according to nature and forest, where people live and which connection they have to the Skedalaskogen.
The Skedalaskogen is a quite big area, totally 830 hectares. The area have about 100 000
visitors a year.
Buntning av grot med lastbilsmonterad utrustning :
During the transportation of logging residues (LR) the material´s low Density is a problem that results in low use of pay-load capacity. Comminution or compression of LR are possible methods to increase pay-loads. In the present thesis studied a bundling machine which was mounted on a truck chassis, and the subsequent transport and crushing. The truck bundler created bundles that were larger and longer than other bundling equipment on the market. The objectives were to determine the total time consumption and its allocation over work element and machinery, to measure dry matter (DM) content of green and brown LR-bundles.
Mikrosimulering för analys av Mästergatans förlängning i Enköping
Two of the main approach roads into the city of Enköping are Salavägen and Stockholmsvägen. They are connected to each other through the street Bangårdsgatan in the roundabout Salatullen and crossing Fannakorset, respectively. These crossings are from time to time heavily loaded, which is why the municipality plan for a new street in parallel to Bangårdsgatan. The traffic will then be spread out and is thereby reducing the Density. The new street is actually an extension of the existing Mästergatan, a side street to Salavägen, to the east and connecting it to Stockholmsvägen or a street nearby.The purpose of this Master thesis is to show how the new street can be drawn in order to discharge the traffic in the area between the roundabout Salatullen and the crossing Fannakorset.
Resistenta rapsbaggar :
Oilseed rape crops are an important in southern Sweden because of the high intensity
of wheat growing. Pollen beetles are the most important pest in oilseed rape and
causes often economic losses. Therefore it?s of great importance that we can control
the population Density, e g by using insecticides if necessary, to avoid mayor yield
losses.
In year 2000 pollen beetles were numerous in the province of Östergötland. The
farmers sprayed with insecticides several times, but with low effects on the beetles.
Field trials and laboratory experiments showed that pollen beetles had developed
resistance against pyrethroids.
Effektivare energianvändning på Totebo AB
The main goal with this thesis report was to come up with ideas of how to make the use of energy more effective and thus save money for the company.First a survey was made to find out where and how the energy consumers were divided within the company. The results were then used in calculations to find out how much money that could be saved and how long it would take to get back the investments.There is a big potential in saving money by recovering heat from the UV-lamps with a heat exchanger. It would also even out the pressure in the factory which is a source to heat loss and a cause for discomfort amongst the employees. It?s possible to save 105 000 kr in a year and the money needed for the investments is 600 000 kr.By using the recovery air more effectively the company could save up to 250 000 kr a year in lowered heat purchases, but this would require the use of automatic dampers.If you reschedule the running times for the wood chipper and invest in some kind of load management, for example Sydkraft?s ?Energidirigent? you can save at least 42 000 kr.
Klassning av fjällbjörkskog enligt FAO:s definition av skogsmark med hjälp av flygburen laserskanning
Sweden?s forestry legislation was updated in 2010 and a new definition of forest land was introduced. This definition was adapted to the one used by the Food and Agriculture Organization of the United Nations (FAO) for international statistics on the state of the world's forests. It is in short based on the lands ability to grow forest that reaches 5 meters, 10 % canopy closure and has a continuous distribution, according to FAO at least 0.5 hectares. A country-wide laser scanning is now carried out for the production of a new national elevation model; the laser data also provides information on forest height and Density.